1 //===--- SemaExpr.cpp - Semantic Analysis for Expressions -----------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements semantic analysis for expressions.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "clang/Sema/SemaInternal.h"
15 #include "TreeTransform.h"
16 #include "clang/AST/ASTConsumer.h"
17 #include "clang/AST/ASTContext.h"
18 #include "clang/AST/ASTLambda.h"
19 #include "clang/AST/ASTMutationListener.h"
20 #include "clang/AST/CXXInheritance.h"
21 #include "clang/AST/DeclObjC.h"
22 #include "clang/AST/DeclTemplate.h"
23 #include "clang/AST/EvaluatedExprVisitor.h"
24 #include "clang/AST/Expr.h"
25 #include "clang/AST/ExprCXX.h"
26 #include "clang/AST/ExprObjC.h"
27 #include "clang/AST/ExprOpenMP.h"
28 #include "clang/AST/RecursiveASTVisitor.h"
29 #include "clang/AST/TypeLoc.h"
30 #include "clang/Basic/PartialDiagnostic.h"
31 #include "clang/Basic/SourceManager.h"
32 #include "clang/Basic/TargetInfo.h"
33 #include "clang/Lex/LiteralSupport.h"
34 #include "clang/Lex/Preprocessor.h"
35 #include "clang/Sema/AnalysisBasedWarnings.h"
36 #include "clang/Sema/DeclSpec.h"
37 #include "clang/Sema/DelayedDiagnostic.h"
38 #include "clang/Sema/Designator.h"
39 #include "clang/Sema/Initialization.h"
40 #include "clang/Sema/Lookup.h"
41 #include "clang/Sema/ParsedTemplate.h"
42 #include "clang/Sema/Scope.h"
43 #include "clang/Sema/ScopeInfo.h"
44 #include "clang/Sema/SemaFixItUtils.h"
45 #include "clang/Sema/Template.h"
46 #include "llvm/Support/ConvertUTF.h"
47 using namespace clang;
48 using namespace sema;
49
50 /// \brief Determine whether the use of this declaration is valid, without
51 /// emitting diagnostics.
CanUseDecl(NamedDecl * D)52 bool Sema::CanUseDecl(NamedDecl *D) {
53 // See if this is an auto-typed variable whose initializer we are parsing.
54 if (ParsingInitForAutoVars.count(D))
55 return false;
56
57 // See if this is a deleted function.
58 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
59 if (FD->isDeleted())
60 return false;
61
62 // If the function has a deduced return type, and we can't deduce it,
63 // then we can't use it either.
64 if (getLangOpts().CPlusPlus14 && FD->getReturnType()->isUndeducedType() &&
65 DeduceReturnType(FD, SourceLocation(), /*Diagnose*/ false))
66 return false;
67 }
68
69 // See if this function is unavailable.
70 if (D->getAvailability() == AR_Unavailable &&
71 cast<Decl>(CurContext)->getAvailability() != AR_Unavailable)
72 return false;
73
74 return true;
75 }
76
DiagnoseUnusedOfDecl(Sema & S,NamedDecl * D,SourceLocation Loc)77 static void DiagnoseUnusedOfDecl(Sema &S, NamedDecl *D, SourceLocation Loc) {
78 // Warn if this is used but marked unused.
79 if (D->hasAttr<UnusedAttr>()) {
80 const Decl *DC = cast_or_null<Decl>(S.getCurObjCLexicalContext());
81 if (DC && !DC->hasAttr<UnusedAttr>())
82 S.Diag(Loc, diag::warn_used_but_marked_unused) << D->getDeclName();
83 }
84 }
85
HasRedeclarationWithoutAvailabilityInCategory(const Decl * D)86 static bool HasRedeclarationWithoutAvailabilityInCategory(const Decl *D) {
87 const auto *OMD = dyn_cast<ObjCMethodDecl>(D);
88 if (!OMD)
89 return false;
90 const ObjCInterfaceDecl *OID = OMD->getClassInterface();
91 if (!OID)
92 return false;
93
94 for (const ObjCCategoryDecl *Cat : OID->visible_categories())
95 if (ObjCMethodDecl *CatMeth =
96 Cat->getMethod(OMD->getSelector(), OMD->isInstanceMethod()))
97 if (!CatMeth->hasAttr<AvailabilityAttr>())
98 return true;
99 return false;
100 }
101
102 static AvailabilityResult
DiagnoseAvailabilityOfDecl(Sema & S,NamedDecl * D,SourceLocation Loc,const ObjCInterfaceDecl * UnknownObjCClass,bool ObjCPropertyAccess)103 DiagnoseAvailabilityOfDecl(Sema &S, NamedDecl *D, SourceLocation Loc,
104 const ObjCInterfaceDecl *UnknownObjCClass,
105 bool ObjCPropertyAccess) {
106 // See if this declaration is unavailable or deprecated.
107 std::string Message;
108 AvailabilityResult Result = D->getAvailability(&Message);
109
110 // For typedefs, if the typedef declaration appears available look
111 // to the underlying type to see if it is more restrictive.
112 while (const TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(D)) {
113 if (Result == AR_Available) {
114 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) {
115 D = TT->getDecl();
116 Result = D->getAvailability(&Message);
117 continue;
118 }
119 }
120 break;
121 }
122
123 // Forward class declarations get their attributes from their definition.
124 if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(D)) {
125 if (IDecl->getDefinition()) {
126 D = IDecl->getDefinition();
127 Result = D->getAvailability(&Message);
128 }
129 }
130
131 if (const EnumConstantDecl *ECD = dyn_cast<EnumConstantDecl>(D))
132 if (Result == AR_Available) {
133 const DeclContext *DC = ECD->getDeclContext();
134 if (const EnumDecl *TheEnumDecl = dyn_cast<EnumDecl>(DC))
135 Result = TheEnumDecl->getAvailability(&Message);
136 }
137
138 const ObjCPropertyDecl *ObjCPDecl = nullptr;
139 if (Result == AR_Deprecated || Result == AR_Unavailable ||
140 AR_NotYetIntroduced) {
141 if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
142 if (const ObjCPropertyDecl *PD = MD->findPropertyDecl()) {
143 AvailabilityResult PDeclResult = PD->getAvailability(nullptr);
144 if (PDeclResult == Result)
145 ObjCPDecl = PD;
146 }
147 }
148 }
149
150 switch (Result) {
151 case AR_Available:
152 break;
153
154 case AR_Deprecated:
155 if (S.getCurContextAvailability() != AR_Deprecated)
156 S.EmitAvailabilityWarning(Sema::AD_Deprecation,
157 D, Message, Loc, UnknownObjCClass, ObjCPDecl,
158 ObjCPropertyAccess);
159 break;
160
161 case AR_NotYetIntroduced: {
162 // Don't do this for enums, they can't be redeclared.
163 if (isa<EnumConstantDecl>(D) || isa<EnumDecl>(D))
164 break;
165
166 bool Warn = !D->getAttr<AvailabilityAttr>()->isInherited();
167 // Objective-C method declarations in categories are not modelled as
168 // redeclarations, so manually look for a redeclaration in a category
169 // if necessary.
170 if (Warn && HasRedeclarationWithoutAvailabilityInCategory(D))
171 Warn = false;
172 // In general, D will point to the most recent redeclaration. However,
173 // for `@class A;` decls, this isn't true -- manually go through the
174 // redecl chain in that case.
175 if (Warn && isa<ObjCInterfaceDecl>(D))
176 for (Decl *Redecl = D->getMostRecentDecl(); Redecl && Warn;
177 Redecl = Redecl->getPreviousDecl())
178 if (!Redecl->hasAttr<AvailabilityAttr>() ||
179 Redecl->getAttr<AvailabilityAttr>()->isInherited())
180 Warn = false;
181
182 if (Warn)
183 S.EmitAvailabilityWarning(Sema::AD_Partial, D, Message, Loc,
184 UnknownObjCClass, ObjCPDecl,
185 ObjCPropertyAccess);
186 break;
187 }
188
189 case AR_Unavailable:
190 if (S.getCurContextAvailability() != AR_Unavailable)
191 S.EmitAvailabilityWarning(Sema::AD_Unavailable,
192 D, Message, Loc, UnknownObjCClass, ObjCPDecl,
193 ObjCPropertyAccess);
194 break;
195
196 }
197 return Result;
198 }
199
200 /// \brief Emit a note explaining that this function is deleted.
NoteDeletedFunction(FunctionDecl * Decl)201 void Sema::NoteDeletedFunction(FunctionDecl *Decl) {
202 assert(Decl->isDeleted());
203
204 CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Decl);
205
206 if (Method && Method->isDeleted() && Method->isDefaulted()) {
207 // If the method was explicitly defaulted, point at that declaration.
208 if (!Method->isImplicit())
209 Diag(Decl->getLocation(), diag::note_implicitly_deleted);
210
211 // Try to diagnose why this special member function was implicitly
212 // deleted. This might fail, if that reason no longer applies.
213 CXXSpecialMember CSM = getSpecialMember(Method);
214 if (CSM != CXXInvalid)
215 ShouldDeleteSpecialMember(Method, CSM, /*Diagnose=*/true);
216
217 return;
218 }
219
220 if (CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(Decl)) {
221 if (CXXConstructorDecl *BaseCD =
222 const_cast<CXXConstructorDecl*>(CD->getInheritedConstructor())) {
223 Diag(Decl->getLocation(), diag::note_inherited_deleted_here);
224 if (BaseCD->isDeleted()) {
225 NoteDeletedFunction(BaseCD);
226 } else {
227 // FIXME: An explanation of why exactly it can't be inherited
228 // would be nice.
229 Diag(BaseCD->getLocation(), diag::note_cannot_inherit);
230 }
231 return;
232 }
233 }
234
235 Diag(Decl->getLocation(), diag::note_availability_specified_here)
236 << Decl << true;
237 }
238
239 /// \brief Determine whether a FunctionDecl was ever declared with an
240 /// explicit storage class.
hasAnyExplicitStorageClass(const FunctionDecl * D)241 static bool hasAnyExplicitStorageClass(const FunctionDecl *D) {
242 for (auto I : D->redecls()) {
243 if (I->getStorageClass() != SC_None)
244 return true;
245 }
246 return false;
247 }
248
249 /// \brief Check whether we're in an extern inline function and referring to a
250 /// variable or function with internal linkage (C11 6.7.4p3).
251 ///
252 /// This is only a warning because we used to silently accept this code, but
253 /// in many cases it will not behave correctly. This is not enabled in C++ mode
254 /// because the restriction language is a bit weaker (C++11 [basic.def.odr]p6)
255 /// and so while there may still be user mistakes, most of the time we can't
256 /// prove that there are errors.
diagnoseUseOfInternalDeclInInlineFunction(Sema & S,const NamedDecl * D,SourceLocation Loc)257 static void diagnoseUseOfInternalDeclInInlineFunction(Sema &S,
258 const NamedDecl *D,
259 SourceLocation Loc) {
260 // This is disabled under C++; there are too many ways for this to fire in
261 // contexts where the warning is a false positive, or where it is technically
262 // correct but benign.
263 if (S.getLangOpts().CPlusPlus)
264 return;
265
266 // Check if this is an inlined function or method.
267 FunctionDecl *Current = S.getCurFunctionDecl();
268 if (!Current)
269 return;
270 if (!Current->isInlined())
271 return;
272 if (!Current->isExternallyVisible())
273 return;
274
275 // Check if the decl has internal linkage.
276 if (D->getFormalLinkage() != InternalLinkage)
277 return;
278
279 // Downgrade from ExtWarn to Extension if
280 // (1) the supposedly external inline function is in the main file,
281 // and probably won't be included anywhere else.
282 // (2) the thing we're referencing is a pure function.
283 // (3) the thing we're referencing is another inline function.
284 // This last can give us false negatives, but it's better than warning on
285 // wrappers for simple C library functions.
286 const FunctionDecl *UsedFn = dyn_cast<FunctionDecl>(D);
287 bool DowngradeWarning = S.getSourceManager().isInMainFile(Loc);
288 if (!DowngradeWarning && UsedFn)
289 DowngradeWarning = UsedFn->isInlined() || UsedFn->hasAttr<ConstAttr>();
290
291 S.Diag(Loc, DowngradeWarning ? diag::ext_internal_in_extern_inline_quiet
292 : diag::ext_internal_in_extern_inline)
293 << /*IsVar=*/!UsedFn << D;
294
295 S.MaybeSuggestAddingStaticToDecl(Current);
296
297 S.Diag(D->getCanonicalDecl()->getLocation(), diag::note_entity_declared_at)
298 << D;
299 }
300
MaybeSuggestAddingStaticToDecl(const FunctionDecl * Cur)301 void Sema::MaybeSuggestAddingStaticToDecl(const FunctionDecl *Cur) {
302 const FunctionDecl *First = Cur->getFirstDecl();
303
304 // Suggest "static" on the function, if possible.
305 if (!hasAnyExplicitStorageClass(First)) {
306 SourceLocation DeclBegin = First->getSourceRange().getBegin();
307 Diag(DeclBegin, diag::note_convert_inline_to_static)
308 << Cur << FixItHint::CreateInsertion(DeclBegin, "static ");
309 }
310 }
311
312 /// \brief Determine whether the use of this declaration is valid, and
313 /// emit any corresponding diagnostics.
314 ///
315 /// This routine diagnoses various problems with referencing
316 /// declarations that can occur when using a declaration. For example,
317 /// it might warn if a deprecated or unavailable declaration is being
318 /// used, or produce an error (and return true) if a C++0x deleted
319 /// function is being used.
320 ///
321 /// \returns true if there was an error (this declaration cannot be
322 /// referenced), false otherwise.
323 ///
DiagnoseUseOfDecl(NamedDecl * D,SourceLocation Loc,const ObjCInterfaceDecl * UnknownObjCClass,bool ObjCPropertyAccess)324 bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc,
325 const ObjCInterfaceDecl *UnknownObjCClass,
326 bool ObjCPropertyAccess) {
327 if (getLangOpts().CPlusPlus && isa<FunctionDecl>(D)) {
328 // If there were any diagnostics suppressed by template argument deduction,
329 // emit them now.
330 auto Pos = SuppressedDiagnostics.find(D->getCanonicalDecl());
331 if (Pos != SuppressedDiagnostics.end()) {
332 for (const PartialDiagnosticAt &Suppressed : Pos->second)
333 Diag(Suppressed.first, Suppressed.second);
334
335 // Clear out the list of suppressed diagnostics, so that we don't emit
336 // them again for this specialization. However, we don't obsolete this
337 // entry from the table, because we want to avoid ever emitting these
338 // diagnostics again.
339 Pos->second.clear();
340 }
341
342 // C++ [basic.start.main]p3:
343 // The function 'main' shall not be used within a program.
344 if (cast<FunctionDecl>(D)->isMain())
345 Diag(Loc, diag::ext_main_used);
346 }
347
348 // See if this is an auto-typed variable whose initializer we are parsing.
349 if (ParsingInitForAutoVars.count(D)) {
350 const AutoType *AT = cast<VarDecl>(D)->getType()->getContainedAutoType();
351
352 Diag(Loc, diag::err_auto_variable_cannot_appear_in_own_initializer)
353 << D->getDeclName() << (unsigned)AT->getKeyword();
354 return true;
355 }
356
357 // See if this is a deleted function.
358 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
359 if (FD->isDeleted()) {
360 Diag(Loc, diag::err_deleted_function_use);
361 NoteDeletedFunction(FD);
362 return true;
363 }
364
365 // If the function has a deduced return type, and we can't deduce it,
366 // then we can't use it either.
367 if (getLangOpts().CPlusPlus14 && FD->getReturnType()->isUndeducedType() &&
368 DeduceReturnType(FD, Loc))
369 return true;
370 }
371 DiagnoseAvailabilityOfDecl(*this, D, Loc, UnknownObjCClass,
372 ObjCPropertyAccess);
373
374 DiagnoseUnusedOfDecl(*this, D, Loc);
375
376 diagnoseUseOfInternalDeclInInlineFunction(*this, D, Loc);
377
378 return false;
379 }
380
381 /// \brief Retrieve the message suffix that should be added to a
382 /// diagnostic complaining about the given function being deleted or
383 /// unavailable.
getDeletedOrUnavailableSuffix(const FunctionDecl * FD)384 std::string Sema::getDeletedOrUnavailableSuffix(const FunctionDecl *FD) {
385 std::string Message;
386 if (FD->getAvailability(&Message))
387 return ": " + Message;
388
389 return std::string();
390 }
391
392 /// DiagnoseSentinelCalls - This routine checks whether a call or
393 /// message-send is to a declaration with the sentinel attribute, and
394 /// if so, it checks that the requirements of the sentinel are
395 /// satisfied.
DiagnoseSentinelCalls(NamedDecl * D,SourceLocation Loc,ArrayRef<Expr * > Args)396 void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc,
397 ArrayRef<Expr *> Args) {
398 const SentinelAttr *attr = D->getAttr<SentinelAttr>();
399 if (!attr)
400 return;
401
402 // The number of formal parameters of the declaration.
403 unsigned numFormalParams;
404
405 // The kind of declaration. This is also an index into a %select in
406 // the diagnostic.
407 enum CalleeType { CT_Function, CT_Method, CT_Block } calleeType;
408
409 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
410 numFormalParams = MD->param_size();
411 calleeType = CT_Method;
412 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
413 numFormalParams = FD->param_size();
414 calleeType = CT_Function;
415 } else if (isa<VarDecl>(D)) {
416 QualType type = cast<ValueDecl>(D)->getType();
417 const FunctionType *fn = nullptr;
418 if (const PointerType *ptr = type->getAs<PointerType>()) {
419 fn = ptr->getPointeeType()->getAs<FunctionType>();
420 if (!fn) return;
421 calleeType = CT_Function;
422 } else if (const BlockPointerType *ptr = type->getAs<BlockPointerType>()) {
423 fn = ptr->getPointeeType()->castAs<FunctionType>();
424 calleeType = CT_Block;
425 } else {
426 return;
427 }
428
429 if (const FunctionProtoType *proto = dyn_cast<FunctionProtoType>(fn)) {
430 numFormalParams = proto->getNumParams();
431 } else {
432 numFormalParams = 0;
433 }
434 } else {
435 return;
436 }
437
438 // "nullPos" is the number of formal parameters at the end which
439 // effectively count as part of the variadic arguments. This is
440 // useful if you would prefer to not have *any* formal parameters,
441 // but the language forces you to have at least one.
442 unsigned nullPos = attr->getNullPos();
443 assert((nullPos == 0 || nullPos == 1) && "invalid null position on sentinel");
444 numFormalParams = (nullPos > numFormalParams ? 0 : numFormalParams - nullPos);
445
446 // The number of arguments which should follow the sentinel.
447 unsigned numArgsAfterSentinel = attr->getSentinel();
448
449 // If there aren't enough arguments for all the formal parameters,
450 // the sentinel, and the args after the sentinel, complain.
451 if (Args.size() < numFormalParams + numArgsAfterSentinel + 1) {
452 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName();
453 Diag(D->getLocation(), diag::note_sentinel_here) << int(calleeType);
454 return;
455 }
456
457 // Otherwise, find the sentinel expression.
458 Expr *sentinelExpr = Args[Args.size() - numArgsAfterSentinel - 1];
459 if (!sentinelExpr) return;
460 if (sentinelExpr->isValueDependent()) return;
461 if (Context.isSentinelNullExpr(sentinelExpr)) return;
462
463 // Pick a reasonable string to insert. Optimistically use 'nil', 'nullptr',
464 // or 'NULL' if those are actually defined in the context. Only use
465 // 'nil' for ObjC methods, where it's much more likely that the
466 // variadic arguments form a list of object pointers.
467 SourceLocation MissingNilLoc
468 = getLocForEndOfToken(sentinelExpr->getLocEnd());
469 std::string NullValue;
470 if (calleeType == CT_Method && PP.isMacroDefined("nil"))
471 NullValue = "nil";
472 else if (getLangOpts().CPlusPlus11)
473 NullValue = "nullptr";
474 else if (PP.isMacroDefined("NULL"))
475 NullValue = "NULL";
476 else
477 NullValue = "(void*) 0";
478
479 if (MissingNilLoc.isInvalid())
480 Diag(Loc, diag::warn_missing_sentinel) << int(calleeType);
481 else
482 Diag(MissingNilLoc, diag::warn_missing_sentinel)
483 << int(calleeType)
484 << FixItHint::CreateInsertion(MissingNilLoc, ", " + NullValue);
485 Diag(D->getLocation(), diag::note_sentinel_here) << int(calleeType);
486 }
487
getExprRange(Expr * E) const488 SourceRange Sema::getExprRange(Expr *E) const {
489 return E ? E->getSourceRange() : SourceRange();
490 }
491
492 //===----------------------------------------------------------------------===//
493 // Standard Promotions and Conversions
494 //===----------------------------------------------------------------------===//
495
496 /// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4).
DefaultFunctionArrayConversion(Expr * E,bool Diagnose)497 ExprResult Sema::DefaultFunctionArrayConversion(Expr *E, bool Diagnose) {
498 // Handle any placeholder expressions which made it here.
499 if (E->getType()->isPlaceholderType()) {
500 ExprResult result = CheckPlaceholderExpr(E);
501 if (result.isInvalid()) return ExprError();
502 E = result.get();
503 }
504
505 QualType Ty = E->getType();
506 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type");
507
508 if (Ty->isFunctionType()) {
509 // If we are here, we are not calling a function but taking
510 // its address (which is not allowed in OpenCL v1.0 s6.8.a.3).
511 if (getLangOpts().OpenCL) {
512 if (Diagnose)
513 Diag(E->getExprLoc(), diag::err_opencl_taking_function_address);
514 return ExprError();
515 }
516
517 if (auto *DRE = dyn_cast<DeclRefExpr>(E->IgnoreParenCasts()))
518 if (auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl()))
519 if (!checkAddressOfFunctionIsAvailable(FD, Diagnose, E->getExprLoc()))
520 return ExprError();
521
522 E = ImpCastExprToType(E, Context.getPointerType(Ty),
523 CK_FunctionToPointerDecay).get();
524 } else if (Ty->isArrayType()) {
525 // In C90 mode, arrays only promote to pointers if the array expression is
526 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has
527 // type 'array of type' is converted to an expression that has type 'pointer
528 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression
529 // that has type 'array of type' ...". The relevant change is "an lvalue"
530 // (C90) to "an expression" (C99).
531 //
532 // C++ 4.2p1:
533 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of
534 // T" can be converted to an rvalue of type "pointer to T".
535 //
536 if (getLangOpts().C99 || getLangOpts().CPlusPlus || E->isLValue())
537 E = ImpCastExprToType(E, Context.getArrayDecayedType(Ty),
538 CK_ArrayToPointerDecay).get();
539 }
540 return E;
541 }
542
CheckForNullPointerDereference(Sema & S,Expr * E)543 static void CheckForNullPointerDereference(Sema &S, Expr *E) {
544 // Check to see if we are dereferencing a null pointer. If so,
545 // and if not volatile-qualified, this is undefined behavior that the
546 // optimizer will delete, so warn about it. People sometimes try to use this
547 // to get a deterministic trap and are surprised by clang's behavior. This
548 // only handles the pattern "*null", which is a very syntactic check.
549 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E->IgnoreParenCasts()))
550 if (UO->getOpcode() == UO_Deref &&
551 UO->getSubExpr()->IgnoreParenCasts()->
552 isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNotNull) &&
553 !UO->getType().isVolatileQualified()) {
554 S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO,
555 S.PDiag(diag::warn_indirection_through_null)
556 << UO->getSubExpr()->getSourceRange());
557 S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO,
558 S.PDiag(diag::note_indirection_through_null));
559 }
560 }
561
DiagnoseDirectIsaAccess(Sema & S,const ObjCIvarRefExpr * OIRE,SourceLocation AssignLoc,const Expr * RHS)562 static void DiagnoseDirectIsaAccess(Sema &S, const ObjCIvarRefExpr *OIRE,
563 SourceLocation AssignLoc,
564 const Expr* RHS) {
565 const ObjCIvarDecl *IV = OIRE->getDecl();
566 if (!IV)
567 return;
568
569 DeclarationName MemberName = IV->getDeclName();
570 IdentifierInfo *Member = MemberName.getAsIdentifierInfo();
571 if (!Member || !Member->isStr("isa"))
572 return;
573
574 const Expr *Base = OIRE->getBase();
575 QualType BaseType = Base->getType();
576 if (OIRE->isArrow())
577 BaseType = BaseType->getPointeeType();
578 if (const ObjCObjectType *OTy = BaseType->getAs<ObjCObjectType>())
579 if (ObjCInterfaceDecl *IDecl = OTy->getInterface()) {
580 ObjCInterfaceDecl *ClassDeclared = nullptr;
581 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared);
582 if (!ClassDeclared->getSuperClass()
583 && (*ClassDeclared->ivar_begin()) == IV) {
584 if (RHS) {
585 NamedDecl *ObjectSetClass =
586 S.LookupSingleName(S.TUScope,
587 &S.Context.Idents.get("object_setClass"),
588 SourceLocation(), S.LookupOrdinaryName);
589 if (ObjectSetClass) {
590 SourceLocation RHSLocEnd = S.getLocForEndOfToken(RHS->getLocEnd());
591 S.Diag(OIRE->getExprLoc(), diag::warn_objc_isa_assign) <<
592 FixItHint::CreateInsertion(OIRE->getLocStart(), "object_setClass(") <<
593 FixItHint::CreateReplacement(SourceRange(OIRE->getOpLoc(),
594 AssignLoc), ",") <<
595 FixItHint::CreateInsertion(RHSLocEnd, ")");
596 }
597 else
598 S.Diag(OIRE->getLocation(), diag::warn_objc_isa_assign);
599 } else {
600 NamedDecl *ObjectGetClass =
601 S.LookupSingleName(S.TUScope,
602 &S.Context.Idents.get("object_getClass"),
603 SourceLocation(), S.LookupOrdinaryName);
604 if (ObjectGetClass)
605 S.Diag(OIRE->getExprLoc(), diag::warn_objc_isa_use) <<
606 FixItHint::CreateInsertion(OIRE->getLocStart(), "object_getClass(") <<
607 FixItHint::CreateReplacement(
608 SourceRange(OIRE->getOpLoc(),
609 OIRE->getLocEnd()), ")");
610 else
611 S.Diag(OIRE->getLocation(), diag::warn_objc_isa_use);
612 }
613 S.Diag(IV->getLocation(), diag::note_ivar_decl);
614 }
615 }
616 }
617
DefaultLvalueConversion(Expr * E)618 ExprResult Sema::DefaultLvalueConversion(Expr *E) {
619 // Handle any placeholder expressions which made it here.
620 if (E->getType()->isPlaceholderType()) {
621 ExprResult result = CheckPlaceholderExpr(E);
622 if (result.isInvalid()) return ExprError();
623 E = result.get();
624 }
625
626 // C++ [conv.lval]p1:
627 // A glvalue of a non-function, non-array type T can be
628 // converted to a prvalue.
629 if (!E->isGLValue()) return E;
630
631 QualType T = E->getType();
632 assert(!T.isNull() && "r-value conversion on typeless expression?");
633
634 // We don't want to throw lvalue-to-rvalue casts on top of
635 // expressions of certain types in C++.
636 if (getLangOpts().CPlusPlus &&
637 (E->getType() == Context.OverloadTy ||
638 T->isDependentType() ||
639 T->isRecordType()))
640 return E;
641
642 // The C standard is actually really unclear on this point, and
643 // DR106 tells us what the result should be but not why. It's
644 // generally best to say that void types just doesn't undergo
645 // lvalue-to-rvalue at all. Note that expressions of unqualified
646 // 'void' type are never l-values, but qualified void can be.
647 if (T->isVoidType())
648 return E;
649
650 // OpenCL usually rejects direct accesses to values of 'half' type.
651 if (getLangOpts().OpenCL && !getOpenCLOptions().cl_khr_fp16 &&
652 T->isHalfType()) {
653 Diag(E->getExprLoc(), diag::err_opencl_half_load_store)
654 << 0 << T;
655 return ExprError();
656 }
657
658 CheckForNullPointerDereference(*this, E);
659 if (const ObjCIsaExpr *OISA = dyn_cast<ObjCIsaExpr>(E->IgnoreParenCasts())) {
660 NamedDecl *ObjectGetClass = LookupSingleName(TUScope,
661 &Context.Idents.get("object_getClass"),
662 SourceLocation(), LookupOrdinaryName);
663 if (ObjectGetClass)
664 Diag(E->getExprLoc(), diag::warn_objc_isa_use) <<
665 FixItHint::CreateInsertion(OISA->getLocStart(), "object_getClass(") <<
666 FixItHint::CreateReplacement(
667 SourceRange(OISA->getOpLoc(), OISA->getIsaMemberLoc()), ")");
668 else
669 Diag(E->getExprLoc(), diag::warn_objc_isa_use);
670 }
671 else if (const ObjCIvarRefExpr *OIRE =
672 dyn_cast<ObjCIvarRefExpr>(E->IgnoreParenCasts()))
673 DiagnoseDirectIsaAccess(*this, OIRE, SourceLocation(), /* Expr*/nullptr);
674
675 // C++ [conv.lval]p1:
676 // [...] If T is a non-class type, the type of the prvalue is the
677 // cv-unqualified version of T. Otherwise, the type of the
678 // rvalue is T.
679 //
680 // C99 6.3.2.1p2:
681 // If the lvalue has qualified type, the value has the unqualified
682 // version of the type of the lvalue; otherwise, the value has the
683 // type of the lvalue.
684 if (T.hasQualifiers())
685 T = T.getUnqualifiedType();
686
687 // Under the MS ABI, lock down the inheritance model now.
688 if (T->isMemberPointerType() &&
689 Context.getTargetInfo().getCXXABI().isMicrosoft())
690 (void)isCompleteType(E->getExprLoc(), T);
691
692 UpdateMarkingForLValueToRValue(E);
693
694 // Loading a __weak object implicitly retains the value, so we need a cleanup to
695 // balance that.
696 if (getLangOpts().ObjCAutoRefCount &&
697 E->getType().getObjCLifetime() == Qualifiers::OCL_Weak)
698 ExprNeedsCleanups = true;
699
700 ExprResult Res = ImplicitCastExpr::Create(Context, T, CK_LValueToRValue, E,
701 nullptr, VK_RValue);
702
703 // C11 6.3.2.1p2:
704 // ... if the lvalue has atomic type, the value has the non-atomic version
705 // of the type of the lvalue ...
706 if (const AtomicType *Atomic = T->getAs<AtomicType>()) {
707 T = Atomic->getValueType().getUnqualifiedType();
708 Res = ImplicitCastExpr::Create(Context, T, CK_AtomicToNonAtomic, Res.get(),
709 nullptr, VK_RValue);
710 }
711
712 return Res;
713 }
714
DefaultFunctionArrayLvalueConversion(Expr * E,bool Diagnose)715 ExprResult Sema::DefaultFunctionArrayLvalueConversion(Expr *E, bool Diagnose) {
716 ExprResult Res = DefaultFunctionArrayConversion(E, Diagnose);
717 if (Res.isInvalid())
718 return ExprError();
719 Res = DefaultLvalueConversion(Res.get());
720 if (Res.isInvalid())
721 return ExprError();
722 return Res;
723 }
724
725 /// CallExprUnaryConversions - a special case of an unary conversion
726 /// performed on a function designator of a call expression.
CallExprUnaryConversions(Expr * E)727 ExprResult Sema::CallExprUnaryConversions(Expr *E) {
728 QualType Ty = E->getType();
729 ExprResult Res = E;
730 // Only do implicit cast for a function type, but not for a pointer
731 // to function type.
732 if (Ty->isFunctionType()) {
733 Res = ImpCastExprToType(E, Context.getPointerType(Ty),
734 CK_FunctionToPointerDecay).get();
735 if (Res.isInvalid())
736 return ExprError();
737 }
738 Res = DefaultLvalueConversion(Res.get());
739 if (Res.isInvalid())
740 return ExprError();
741 return Res.get();
742 }
743
744 /// UsualUnaryConversions - Performs various conversions that are common to most
745 /// operators (C99 6.3). The conversions of array and function types are
746 /// sometimes suppressed. For example, the array->pointer conversion doesn't
747 /// apply if the array is an argument to the sizeof or address (&) operators.
748 /// In these instances, this routine should *not* be called.
UsualUnaryConversions(Expr * E)749 ExprResult Sema::UsualUnaryConversions(Expr *E) {
750 // First, convert to an r-value.
751 ExprResult Res = DefaultFunctionArrayLvalueConversion(E);
752 if (Res.isInvalid())
753 return ExprError();
754 E = Res.get();
755
756 QualType Ty = E->getType();
757 assert(!Ty.isNull() && "UsualUnaryConversions - missing type");
758
759 // Half FP have to be promoted to float unless it is natively supported
760 if (Ty->isHalfType() && !getLangOpts().NativeHalfType)
761 return ImpCastExprToType(Res.get(), Context.FloatTy, CK_FloatingCast);
762
763 // Try to perform integral promotions if the object has a theoretically
764 // promotable type.
765 if (Ty->isIntegralOrUnscopedEnumerationType()) {
766 // C99 6.3.1.1p2:
767 //
768 // The following may be used in an expression wherever an int or
769 // unsigned int may be used:
770 // - an object or expression with an integer type whose integer
771 // conversion rank is less than or equal to the rank of int
772 // and unsigned int.
773 // - A bit-field of type _Bool, int, signed int, or unsigned int.
774 //
775 // If an int can represent all values of the original type, the
776 // value is converted to an int; otherwise, it is converted to an
777 // unsigned int. These are called the integer promotions. All
778 // other types are unchanged by the integer promotions.
779
780 QualType PTy = Context.isPromotableBitField(E);
781 if (!PTy.isNull()) {
782 E = ImpCastExprToType(E, PTy, CK_IntegralCast).get();
783 return E;
784 }
785 if (Ty->isPromotableIntegerType()) {
786 QualType PT = Context.getPromotedIntegerType(Ty);
787 E = ImpCastExprToType(E, PT, CK_IntegralCast).get();
788 return E;
789 }
790 }
791 return E;
792 }
793
794 /// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that
795 /// do not have a prototype. Arguments that have type float or __fp16
796 /// are promoted to double. All other argument types are converted by
797 /// UsualUnaryConversions().
DefaultArgumentPromotion(Expr * E)798 ExprResult Sema::DefaultArgumentPromotion(Expr *E) {
799 QualType Ty = E->getType();
800 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type");
801
802 ExprResult Res = UsualUnaryConversions(E);
803 if (Res.isInvalid())
804 return ExprError();
805 E = Res.get();
806
807 // If this is a 'float' or '__fp16' (CVR qualified or typedef) promote to
808 // double.
809 const BuiltinType *BTy = Ty->getAs<BuiltinType>();
810 if (BTy && (BTy->getKind() == BuiltinType::Half ||
811 BTy->getKind() == BuiltinType::Float))
812 E = ImpCastExprToType(E, Context.DoubleTy, CK_FloatingCast).get();
813
814 // C++ performs lvalue-to-rvalue conversion as a default argument
815 // promotion, even on class types, but note:
816 // C++11 [conv.lval]p2:
817 // When an lvalue-to-rvalue conversion occurs in an unevaluated
818 // operand or a subexpression thereof the value contained in the
819 // referenced object is not accessed. Otherwise, if the glvalue
820 // has a class type, the conversion copy-initializes a temporary
821 // of type T from the glvalue and the result of the conversion
822 // is a prvalue for the temporary.
823 // FIXME: add some way to gate this entire thing for correctness in
824 // potentially potentially evaluated contexts.
825 if (getLangOpts().CPlusPlus && E->isGLValue() && !isUnevaluatedContext()) {
826 ExprResult Temp = PerformCopyInitialization(
827 InitializedEntity::InitializeTemporary(E->getType()),
828 E->getExprLoc(), E);
829 if (Temp.isInvalid())
830 return ExprError();
831 E = Temp.get();
832 }
833
834 return E;
835 }
836
837 /// Determine the degree of POD-ness for an expression.
838 /// Incomplete types are considered POD, since this check can be performed
839 /// when we're in an unevaluated context.
isValidVarArgType(const QualType & Ty)840 Sema::VarArgKind Sema::isValidVarArgType(const QualType &Ty) {
841 if (Ty->isIncompleteType()) {
842 // C++11 [expr.call]p7:
843 // After these conversions, if the argument does not have arithmetic,
844 // enumeration, pointer, pointer to member, or class type, the program
845 // is ill-formed.
846 //
847 // Since we've already performed array-to-pointer and function-to-pointer
848 // decay, the only such type in C++ is cv void. This also handles
849 // initializer lists as variadic arguments.
850 if (Ty->isVoidType())
851 return VAK_Invalid;
852
853 if (Ty->isObjCObjectType())
854 return VAK_Invalid;
855 return VAK_Valid;
856 }
857
858 if (Ty.isCXX98PODType(Context))
859 return VAK_Valid;
860
861 // C++11 [expr.call]p7:
862 // Passing a potentially-evaluated argument of class type (Clause 9)
863 // having a non-trivial copy constructor, a non-trivial move constructor,
864 // or a non-trivial destructor, with no corresponding parameter,
865 // is conditionally-supported with implementation-defined semantics.
866 if (getLangOpts().CPlusPlus11 && !Ty->isDependentType())
867 if (CXXRecordDecl *Record = Ty->getAsCXXRecordDecl())
868 if (!Record->hasNonTrivialCopyConstructor() &&
869 !Record->hasNonTrivialMoveConstructor() &&
870 !Record->hasNonTrivialDestructor())
871 return VAK_ValidInCXX11;
872
873 if (getLangOpts().ObjCAutoRefCount && Ty->isObjCLifetimeType())
874 return VAK_Valid;
875
876 if (Ty->isObjCObjectType())
877 return VAK_Invalid;
878
879 if (getLangOpts().MSVCCompat)
880 return VAK_MSVCUndefined;
881
882 // FIXME: In C++11, these cases are conditionally-supported, meaning we're
883 // permitted to reject them. We should consider doing so.
884 return VAK_Undefined;
885 }
886
checkVariadicArgument(const Expr * E,VariadicCallType CT)887 void Sema::checkVariadicArgument(const Expr *E, VariadicCallType CT) {
888 // Don't allow one to pass an Objective-C interface to a vararg.
889 const QualType &Ty = E->getType();
890 VarArgKind VAK = isValidVarArgType(Ty);
891
892 // Complain about passing non-POD types through varargs.
893 switch (VAK) {
894 case VAK_ValidInCXX11:
895 DiagRuntimeBehavior(
896 E->getLocStart(), nullptr,
897 PDiag(diag::warn_cxx98_compat_pass_non_pod_arg_to_vararg)
898 << Ty << CT);
899 // Fall through.
900 case VAK_Valid:
901 if (Ty->isRecordType()) {
902 // This is unlikely to be what the user intended. If the class has a
903 // 'c_str' member function, the user probably meant to call that.
904 DiagRuntimeBehavior(E->getLocStart(), nullptr,
905 PDiag(diag::warn_pass_class_arg_to_vararg)
906 << Ty << CT << hasCStrMethod(E) << ".c_str()");
907 }
908 break;
909
910 case VAK_Undefined:
911 case VAK_MSVCUndefined:
912 DiagRuntimeBehavior(
913 E->getLocStart(), nullptr,
914 PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg)
915 << getLangOpts().CPlusPlus11 << Ty << CT);
916 break;
917
918 case VAK_Invalid:
919 if (Ty->isObjCObjectType())
920 DiagRuntimeBehavior(
921 E->getLocStart(), nullptr,
922 PDiag(diag::err_cannot_pass_objc_interface_to_vararg)
923 << Ty << CT);
924 else
925 Diag(E->getLocStart(), diag::err_cannot_pass_to_vararg)
926 << isa<InitListExpr>(E) << Ty << CT;
927 break;
928 }
929 }
930
931 /// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but
932 /// will create a trap if the resulting type is not a POD type.
DefaultVariadicArgumentPromotion(Expr * E,VariadicCallType CT,FunctionDecl * FDecl)933 ExprResult Sema::DefaultVariadicArgumentPromotion(Expr *E, VariadicCallType CT,
934 FunctionDecl *FDecl) {
935 if (const BuiltinType *PlaceholderTy = E->getType()->getAsPlaceholderType()) {
936 // Strip the unbridged-cast placeholder expression off, if applicable.
937 if (PlaceholderTy->getKind() == BuiltinType::ARCUnbridgedCast &&
938 (CT == VariadicMethod ||
939 (FDecl && FDecl->hasAttr<CFAuditedTransferAttr>()))) {
940 E = stripARCUnbridgedCast(E);
941
942 // Otherwise, do normal placeholder checking.
943 } else {
944 ExprResult ExprRes = CheckPlaceholderExpr(E);
945 if (ExprRes.isInvalid())
946 return ExprError();
947 E = ExprRes.get();
948 }
949 }
950
951 ExprResult ExprRes = DefaultArgumentPromotion(E);
952 if (ExprRes.isInvalid())
953 return ExprError();
954 E = ExprRes.get();
955
956 // Diagnostics regarding non-POD argument types are
957 // emitted along with format string checking in Sema::CheckFunctionCall().
958 if (isValidVarArgType(E->getType()) == VAK_Undefined) {
959 // Turn this into a trap.
960 CXXScopeSpec SS;
961 SourceLocation TemplateKWLoc;
962 UnqualifiedId Name;
963 Name.setIdentifier(PP.getIdentifierInfo("__builtin_trap"),
964 E->getLocStart());
965 ExprResult TrapFn = ActOnIdExpression(TUScope, SS, TemplateKWLoc,
966 Name, true, false);
967 if (TrapFn.isInvalid())
968 return ExprError();
969
970 ExprResult Call = ActOnCallExpr(TUScope, TrapFn.get(),
971 E->getLocStart(), None,
972 E->getLocEnd());
973 if (Call.isInvalid())
974 return ExprError();
975
976 ExprResult Comma = ActOnBinOp(TUScope, E->getLocStart(), tok::comma,
977 Call.get(), E);
978 if (Comma.isInvalid())
979 return ExprError();
980 return Comma.get();
981 }
982
983 if (!getLangOpts().CPlusPlus &&
984 RequireCompleteType(E->getExprLoc(), E->getType(),
985 diag::err_call_incomplete_argument))
986 return ExprError();
987
988 return E;
989 }
990
991 /// \brief Converts an integer to complex float type. Helper function of
992 /// UsualArithmeticConversions()
993 ///
994 /// \return false if the integer expression is an integer type and is
995 /// successfully converted to the complex type.
handleIntegerToComplexFloatConversion(Sema & S,ExprResult & IntExpr,ExprResult & ComplexExpr,QualType IntTy,QualType ComplexTy,bool SkipCast)996 static bool handleIntegerToComplexFloatConversion(Sema &S, ExprResult &IntExpr,
997 ExprResult &ComplexExpr,
998 QualType IntTy,
999 QualType ComplexTy,
1000 bool SkipCast) {
1001 if (IntTy->isComplexType() || IntTy->isRealFloatingType()) return true;
1002 if (SkipCast) return false;
1003 if (IntTy->isIntegerType()) {
1004 QualType fpTy = cast<ComplexType>(ComplexTy)->getElementType();
1005 IntExpr = S.ImpCastExprToType(IntExpr.get(), fpTy, CK_IntegralToFloating);
1006 IntExpr = S.ImpCastExprToType(IntExpr.get(), ComplexTy,
1007 CK_FloatingRealToComplex);
1008 } else {
1009 assert(IntTy->isComplexIntegerType());
1010 IntExpr = S.ImpCastExprToType(IntExpr.get(), ComplexTy,
1011 CK_IntegralComplexToFloatingComplex);
1012 }
1013 return false;
1014 }
1015
1016 /// \brief Handle arithmetic conversion with complex types. Helper function of
1017 /// UsualArithmeticConversions()
handleComplexFloatConversion(Sema & S,ExprResult & LHS,ExprResult & RHS,QualType LHSType,QualType RHSType,bool IsCompAssign)1018 static QualType handleComplexFloatConversion(Sema &S, ExprResult &LHS,
1019 ExprResult &RHS, QualType LHSType,
1020 QualType RHSType,
1021 bool IsCompAssign) {
1022 // if we have an integer operand, the result is the complex type.
1023 if (!handleIntegerToComplexFloatConversion(S, RHS, LHS, RHSType, LHSType,
1024 /*skipCast*/false))
1025 return LHSType;
1026 if (!handleIntegerToComplexFloatConversion(S, LHS, RHS, LHSType, RHSType,
1027 /*skipCast*/IsCompAssign))
1028 return RHSType;
1029
1030 // This handles complex/complex, complex/float, or float/complex.
1031 // When both operands are complex, the shorter operand is converted to the
1032 // type of the longer, and that is the type of the result. This corresponds
1033 // to what is done when combining two real floating-point operands.
1034 // The fun begins when size promotion occur across type domains.
1035 // From H&S 6.3.4: When one operand is complex and the other is a real
1036 // floating-point type, the less precise type is converted, within it's
1037 // real or complex domain, to the precision of the other type. For example,
1038 // when combining a "long double" with a "double _Complex", the
1039 // "double _Complex" is promoted to "long double _Complex".
1040
1041 // Compute the rank of the two types, regardless of whether they are complex.
1042 int Order = S.Context.getFloatingTypeOrder(LHSType, RHSType);
1043
1044 auto *LHSComplexType = dyn_cast<ComplexType>(LHSType);
1045 auto *RHSComplexType = dyn_cast<ComplexType>(RHSType);
1046 QualType LHSElementType =
1047 LHSComplexType ? LHSComplexType->getElementType() : LHSType;
1048 QualType RHSElementType =
1049 RHSComplexType ? RHSComplexType->getElementType() : RHSType;
1050
1051 QualType ResultType = S.Context.getComplexType(LHSElementType);
1052 if (Order < 0) {
1053 // Promote the precision of the LHS if not an assignment.
1054 ResultType = S.Context.getComplexType(RHSElementType);
1055 if (!IsCompAssign) {
1056 if (LHSComplexType)
1057 LHS =
1058 S.ImpCastExprToType(LHS.get(), ResultType, CK_FloatingComplexCast);
1059 else
1060 LHS = S.ImpCastExprToType(LHS.get(), RHSElementType, CK_FloatingCast);
1061 }
1062 } else if (Order > 0) {
1063 // Promote the precision of the RHS.
1064 if (RHSComplexType)
1065 RHS = S.ImpCastExprToType(RHS.get(), ResultType, CK_FloatingComplexCast);
1066 else
1067 RHS = S.ImpCastExprToType(RHS.get(), LHSElementType, CK_FloatingCast);
1068 }
1069 return ResultType;
1070 }
1071
1072 /// \brief Hande arithmetic conversion from integer to float. Helper function
1073 /// of UsualArithmeticConversions()
handleIntToFloatConversion(Sema & S,ExprResult & FloatExpr,ExprResult & IntExpr,QualType FloatTy,QualType IntTy,bool ConvertFloat,bool ConvertInt)1074 static QualType handleIntToFloatConversion(Sema &S, ExprResult &FloatExpr,
1075 ExprResult &IntExpr,
1076 QualType FloatTy, QualType IntTy,
1077 bool ConvertFloat, bool ConvertInt) {
1078 if (IntTy->isIntegerType()) {
1079 if (ConvertInt)
1080 // Convert intExpr to the lhs floating point type.
1081 IntExpr = S.ImpCastExprToType(IntExpr.get(), FloatTy,
1082 CK_IntegralToFloating);
1083 return FloatTy;
1084 }
1085
1086 // Convert both sides to the appropriate complex float.
1087 assert(IntTy->isComplexIntegerType());
1088 QualType result = S.Context.getComplexType(FloatTy);
1089
1090 // _Complex int -> _Complex float
1091 if (ConvertInt)
1092 IntExpr = S.ImpCastExprToType(IntExpr.get(), result,
1093 CK_IntegralComplexToFloatingComplex);
1094
1095 // float -> _Complex float
1096 if (ConvertFloat)
1097 FloatExpr = S.ImpCastExprToType(FloatExpr.get(), result,
1098 CK_FloatingRealToComplex);
1099
1100 return result;
1101 }
1102
1103 /// \brief Handle arithmethic conversion with floating point types. Helper
1104 /// function of UsualArithmeticConversions()
handleFloatConversion(Sema & S,ExprResult & LHS,ExprResult & RHS,QualType LHSType,QualType RHSType,bool IsCompAssign)1105 static QualType handleFloatConversion(Sema &S, ExprResult &LHS,
1106 ExprResult &RHS, QualType LHSType,
1107 QualType RHSType, bool IsCompAssign) {
1108 bool LHSFloat = LHSType->isRealFloatingType();
1109 bool RHSFloat = RHSType->isRealFloatingType();
1110
1111 // If we have two real floating types, convert the smaller operand
1112 // to the bigger result.
1113 if (LHSFloat && RHSFloat) {
1114 int order = S.Context.getFloatingTypeOrder(LHSType, RHSType);
1115 if (order > 0) {
1116 RHS = S.ImpCastExprToType(RHS.get(), LHSType, CK_FloatingCast);
1117 return LHSType;
1118 }
1119
1120 assert(order < 0 && "illegal float comparison");
1121 if (!IsCompAssign)
1122 LHS = S.ImpCastExprToType(LHS.get(), RHSType, CK_FloatingCast);
1123 return RHSType;
1124 }
1125
1126 if (LHSFloat) {
1127 // Half FP has to be promoted to float unless it is natively supported
1128 if (LHSType->isHalfType() && !S.getLangOpts().NativeHalfType)
1129 LHSType = S.Context.FloatTy;
1130
1131 return handleIntToFloatConversion(S, LHS, RHS, LHSType, RHSType,
1132 /*convertFloat=*/!IsCompAssign,
1133 /*convertInt=*/ true);
1134 }
1135 assert(RHSFloat);
1136 return handleIntToFloatConversion(S, RHS, LHS, RHSType, LHSType,
1137 /*convertInt=*/ true,
1138 /*convertFloat=*/!IsCompAssign);
1139 }
1140
1141 typedef ExprResult PerformCastFn(Sema &S, Expr *operand, QualType toType);
1142
1143 namespace {
1144 /// These helper callbacks are placed in an anonymous namespace to
1145 /// permit their use as function template parameters.
doIntegralCast(Sema & S,Expr * op,QualType toType)1146 ExprResult doIntegralCast(Sema &S, Expr *op, QualType toType) {
1147 return S.ImpCastExprToType(op, toType, CK_IntegralCast);
1148 }
1149
doComplexIntegralCast(Sema & S,Expr * op,QualType toType)1150 ExprResult doComplexIntegralCast(Sema &S, Expr *op, QualType toType) {
1151 return S.ImpCastExprToType(op, S.Context.getComplexType(toType),
1152 CK_IntegralComplexCast);
1153 }
1154 }
1155
1156 /// \brief Handle integer arithmetic conversions. Helper function of
1157 /// UsualArithmeticConversions()
1158 template <PerformCastFn doLHSCast, PerformCastFn doRHSCast>
handleIntegerConversion(Sema & S,ExprResult & LHS,ExprResult & RHS,QualType LHSType,QualType RHSType,bool IsCompAssign)1159 static QualType handleIntegerConversion(Sema &S, ExprResult &LHS,
1160 ExprResult &RHS, QualType LHSType,
1161 QualType RHSType, bool IsCompAssign) {
1162 // The rules for this case are in C99 6.3.1.8
1163 int order = S.Context.getIntegerTypeOrder(LHSType, RHSType);
1164 bool LHSSigned = LHSType->hasSignedIntegerRepresentation();
1165 bool RHSSigned = RHSType->hasSignedIntegerRepresentation();
1166 if (LHSSigned == RHSSigned) {
1167 // Same signedness; use the higher-ranked type
1168 if (order >= 0) {
1169 RHS = (*doRHSCast)(S, RHS.get(), LHSType);
1170 return LHSType;
1171 } else if (!IsCompAssign)
1172 LHS = (*doLHSCast)(S, LHS.get(), RHSType);
1173 return RHSType;
1174 } else if (order != (LHSSigned ? 1 : -1)) {
1175 // The unsigned type has greater than or equal rank to the
1176 // signed type, so use the unsigned type
1177 if (RHSSigned) {
1178 RHS = (*doRHSCast)(S, RHS.get(), LHSType);
1179 return LHSType;
1180 } else if (!IsCompAssign)
1181 LHS = (*doLHSCast)(S, LHS.get(), RHSType);
1182 return RHSType;
1183 } else if (S.Context.getIntWidth(LHSType) != S.Context.getIntWidth(RHSType)) {
1184 // The two types are different widths; if we are here, that
1185 // means the signed type is larger than the unsigned type, so
1186 // use the signed type.
1187 if (LHSSigned) {
1188 RHS = (*doRHSCast)(S, RHS.get(), LHSType);
1189 return LHSType;
1190 } else if (!IsCompAssign)
1191 LHS = (*doLHSCast)(S, LHS.get(), RHSType);
1192 return RHSType;
1193 } else {
1194 // The signed type is higher-ranked than the unsigned type,
1195 // but isn't actually any bigger (like unsigned int and long
1196 // on most 32-bit systems). Use the unsigned type corresponding
1197 // to the signed type.
1198 QualType result =
1199 S.Context.getCorrespondingUnsignedType(LHSSigned ? LHSType : RHSType);
1200 RHS = (*doRHSCast)(S, RHS.get(), result);
1201 if (!IsCompAssign)
1202 LHS = (*doLHSCast)(S, LHS.get(), result);
1203 return result;
1204 }
1205 }
1206
1207 /// \brief Handle conversions with GCC complex int extension. Helper function
1208 /// of UsualArithmeticConversions()
handleComplexIntConversion(Sema & S,ExprResult & LHS,ExprResult & RHS,QualType LHSType,QualType RHSType,bool IsCompAssign)1209 static QualType handleComplexIntConversion(Sema &S, ExprResult &LHS,
1210 ExprResult &RHS, QualType LHSType,
1211 QualType RHSType,
1212 bool IsCompAssign) {
1213 const ComplexType *LHSComplexInt = LHSType->getAsComplexIntegerType();
1214 const ComplexType *RHSComplexInt = RHSType->getAsComplexIntegerType();
1215
1216 if (LHSComplexInt && RHSComplexInt) {
1217 QualType LHSEltType = LHSComplexInt->getElementType();
1218 QualType RHSEltType = RHSComplexInt->getElementType();
1219 QualType ScalarType =
1220 handleIntegerConversion<doComplexIntegralCast, doComplexIntegralCast>
1221 (S, LHS, RHS, LHSEltType, RHSEltType, IsCompAssign);
1222
1223 return S.Context.getComplexType(ScalarType);
1224 }
1225
1226 if (LHSComplexInt) {
1227 QualType LHSEltType = LHSComplexInt->getElementType();
1228 QualType ScalarType =
1229 handleIntegerConversion<doComplexIntegralCast, doIntegralCast>
1230 (S, LHS, RHS, LHSEltType, RHSType, IsCompAssign);
1231 QualType ComplexType = S.Context.getComplexType(ScalarType);
1232 RHS = S.ImpCastExprToType(RHS.get(), ComplexType,
1233 CK_IntegralRealToComplex);
1234
1235 return ComplexType;
1236 }
1237
1238 assert(RHSComplexInt);
1239
1240 QualType RHSEltType = RHSComplexInt->getElementType();
1241 QualType ScalarType =
1242 handleIntegerConversion<doIntegralCast, doComplexIntegralCast>
1243 (S, LHS, RHS, LHSType, RHSEltType, IsCompAssign);
1244 QualType ComplexType = S.Context.getComplexType(ScalarType);
1245
1246 if (!IsCompAssign)
1247 LHS = S.ImpCastExprToType(LHS.get(), ComplexType,
1248 CK_IntegralRealToComplex);
1249 return ComplexType;
1250 }
1251
1252 /// UsualArithmeticConversions - Performs various conversions that are common to
1253 /// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this
1254 /// routine returns the first non-arithmetic type found. The client is
1255 /// responsible for emitting appropriate error diagnostics.
UsualArithmeticConversions(ExprResult & LHS,ExprResult & RHS,bool IsCompAssign)1256 QualType Sema::UsualArithmeticConversions(ExprResult &LHS, ExprResult &RHS,
1257 bool IsCompAssign) {
1258 if (!IsCompAssign) {
1259 LHS = UsualUnaryConversions(LHS.get());
1260 if (LHS.isInvalid())
1261 return QualType();
1262 }
1263
1264 RHS = UsualUnaryConversions(RHS.get());
1265 if (RHS.isInvalid())
1266 return QualType();
1267
1268 // For conversion purposes, we ignore any qualifiers.
1269 // For example, "const float" and "float" are equivalent.
1270 QualType LHSType =
1271 Context.getCanonicalType(LHS.get()->getType()).getUnqualifiedType();
1272 QualType RHSType =
1273 Context.getCanonicalType(RHS.get()->getType()).getUnqualifiedType();
1274
1275 // For conversion purposes, we ignore any atomic qualifier on the LHS.
1276 if (const AtomicType *AtomicLHS = LHSType->getAs<AtomicType>())
1277 LHSType = AtomicLHS->getValueType();
1278
1279 // If both types are identical, no conversion is needed.
1280 if (LHSType == RHSType)
1281 return LHSType;
1282
1283 // If either side is a non-arithmetic type (e.g. a pointer), we are done.
1284 // The caller can deal with this (e.g. pointer + int).
1285 if (!LHSType->isArithmeticType() || !RHSType->isArithmeticType())
1286 return QualType();
1287
1288 // Apply unary and bitfield promotions to the LHS's type.
1289 QualType LHSUnpromotedType = LHSType;
1290 if (LHSType->isPromotableIntegerType())
1291 LHSType = Context.getPromotedIntegerType(LHSType);
1292 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(LHS.get());
1293 if (!LHSBitfieldPromoteTy.isNull())
1294 LHSType = LHSBitfieldPromoteTy;
1295 if (LHSType != LHSUnpromotedType && !IsCompAssign)
1296 LHS = ImpCastExprToType(LHS.get(), LHSType, CK_IntegralCast);
1297
1298 // If both types are identical, no conversion is needed.
1299 if (LHSType == RHSType)
1300 return LHSType;
1301
1302 // At this point, we have two different arithmetic types.
1303
1304 // Handle complex types first (C99 6.3.1.8p1).
1305 if (LHSType->isComplexType() || RHSType->isComplexType())
1306 return handleComplexFloatConversion(*this, LHS, RHS, LHSType, RHSType,
1307 IsCompAssign);
1308
1309 // Now handle "real" floating types (i.e. float, double, long double).
1310 if (LHSType->isRealFloatingType() || RHSType->isRealFloatingType())
1311 return handleFloatConversion(*this, LHS, RHS, LHSType, RHSType,
1312 IsCompAssign);
1313
1314 // Handle GCC complex int extension.
1315 if (LHSType->isComplexIntegerType() || RHSType->isComplexIntegerType())
1316 return handleComplexIntConversion(*this, LHS, RHS, LHSType, RHSType,
1317 IsCompAssign);
1318
1319 // Finally, we have two differing integer types.
1320 return handleIntegerConversion<doIntegralCast, doIntegralCast>
1321 (*this, LHS, RHS, LHSType, RHSType, IsCompAssign);
1322 }
1323
1324
1325 //===----------------------------------------------------------------------===//
1326 // Semantic Analysis for various Expression Types
1327 //===----------------------------------------------------------------------===//
1328
1329
1330 ExprResult
ActOnGenericSelectionExpr(SourceLocation KeyLoc,SourceLocation DefaultLoc,SourceLocation RParenLoc,Expr * ControllingExpr,ArrayRef<ParsedType> ArgTypes,ArrayRef<Expr * > ArgExprs)1331 Sema::ActOnGenericSelectionExpr(SourceLocation KeyLoc,
1332 SourceLocation DefaultLoc,
1333 SourceLocation RParenLoc,
1334 Expr *ControllingExpr,
1335 ArrayRef<ParsedType> ArgTypes,
1336 ArrayRef<Expr *> ArgExprs) {
1337 unsigned NumAssocs = ArgTypes.size();
1338 assert(NumAssocs == ArgExprs.size());
1339
1340 TypeSourceInfo **Types = new TypeSourceInfo*[NumAssocs];
1341 for (unsigned i = 0; i < NumAssocs; ++i) {
1342 if (ArgTypes[i])
1343 (void) GetTypeFromParser(ArgTypes[i], &Types[i]);
1344 else
1345 Types[i] = nullptr;
1346 }
1347
1348 ExprResult ER = CreateGenericSelectionExpr(KeyLoc, DefaultLoc, RParenLoc,
1349 ControllingExpr,
1350 llvm::makeArrayRef(Types, NumAssocs),
1351 ArgExprs);
1352 delete [] Types;
1353 return ER;
1354 }
1355
1356 ExprResult
CreateGenericSelectionExpr(SourceLocation KeyLoc,SourceLocation DefaultLoc,SourceLocation RParenLoc,Expr * ControllingExpr,ArrayRef<TypeSourceInfo * > Types,ArrayRef<Expr * > Exprs)1357 Sema::CreateGenericSelectionExpr(SourceLocation KeyLoc,
1358 SourceLocation DefaultLoc,
1359 SourceLocation RParenLoc,
1360 Expr *ControllingExpr,
1361 ArrayRef<TypeSourceInfo *> Types,
1362 ArrayRef<Expr *> Exprs) {
1363 unsigned NumAssocs = Types.size();
1364 assert(NumAssocs == Exprs.size());
1365
1366 // Decay and strip qualifiers for the controlling expression type, and handle
1367 // placeholder type replacement. See committee discussion from WG14 DR423.
1368 ExprResult R = DefaultFunctionArrayLvalueConversion(ControllingExpr);
1369 if (R.isInvalid())
1370 return ExprError();
1371 ControllingExpr = R.get();
1372
1373 // The controlling expression is an unevaluated operand, so side effects are
1374 // likely unintended.
1375 if (ActiveTemplateInstantiations.empty() &&
1376 ControllingExpr->HasSideEffects(Context, false))
1377 Diag(ControllingExpr->getExprLoc(),
1378 diag::warn_side_effects_unevaluated_context);
1379
1380 bool TypeErrorFound = false,
1381 IsResultDependent = ControllingExpr->isTypeDependent(),
1382 ContainsUnexpandedParameterPack
1383 = ControllingExpr->containsUnexpandedParameterPack();
1384
1385 for (unsigned i = 0; i < NumAssocs; ++i) {
1386 if (Exprs[i]->containsUnexpandedParameterPack())
1387 ContainsUnexpandedParameterPack = true;
1388
1389 if (Types[i]) {
1390 if (Types[i]->getType()->containsUnexpandedParameterPack())
1391 ContainsUnexpandedParameterPack = true;
1392
1393 if (Types[i]->getType()->isDependentType()) {
1394 IsResultDependent = true;
1395 } else {
1396 // C11 6.5.1.1p2 "The type name in a generic association shall specify a
1397 // complete object type other than a variably modified type."
1398 unsigned D = 0;
1399 if (Types[i]->getType()->isIncompleteType())
1400 D = diag::err_assoc_type_incomplete;
1401 else if (!Types[i]->getType()->isObjectType())
1402 D = diag::err_assoc_type_nonobject;
1403 else if (Types[i]->getType()->isVariablyModifiedType())
1404 D = diag::err_assoc_type_variably_modified;
1405
1406 if (D != 0) {
1407 Diag(Types[i]->getTypeLoc().getBeginLoc(), D)
1408 << Types[i]->getTypeLoc().getSourceRange()
1409 << Types[i]->getType();
1410 TypeErrorFound = true;
1411 }
1412
1413 // C11 6.5.1.1p2 "No two generic associations in the same generic
1414 // selection shall specify compatible types."
1415 for (unsigned j = i+1; j < NumAssocs; ++j)
1416 if (Types[j] && !Types[j]->getType()->isDependentType() &&
1417 Context.typesAreCompatible(Types[i]->getType(),
1418 Types[j]->getType())) {
1419 Diag(Types[j]->getTypeLoc().getBeginLoc(),
1420 diag::err_assoc_compatible_types)
1421 << Types[j]->getTypeLoc().getSourceRange()
1422 << Types[j]->getType()
1423 << Types[i]->getType();
1424 Diag(Types[i]->getTypeLoc().getBeginLoc(),
1425 diag::note_compat_assoc)
1426 << Types[i]->getTypeLoc().getSourceRange()
1427 << Types[i]->getType();
1428 TypeErrorFound = true;
1429 }
1430 }
1431 }
1432 }
1433 if (TypeErrorFound)
1434 return ExprError();
1435
1436 // If we determined that the generic selection is result-dependent, don't
1437 // try to compute the result expression.
1438 if (IsResultDependent)
1439 return new (Context) GenericSelectionExpr(
1440 Context, KeyLoc, ControllingExpr, Types, Exprs, DefaultLoc, RParenLoc,
1441 ContainsUnexpandedParameterPack);
1442
1443 SmallVector<unsigned, 1> CompatIndices;
1444 unsigned DefaultIndex = -1U;
1445 for (unsigned i = 0; i < NumAssocs; ++i) {
1446 if (!Types[i])
1447 DefaultIndex = i;
1448 else if (Context.typesAreCompatible(ControllingExpr->getType(),
1449 Types[i]->getType()))
1450 CompatIndices.push_back(i);
1451 }
1452
1453 // C11 6.5.1.1p2 "The controlling expression of a generic selection shall have
1454 // type compatible with at most one of the types named in its generic
1455 // association list."
1456 if (CompatIndices.size() > 1) {
1457 // We strip parens here because the controlling expression is typically
1458 // parenthesized in macro definitions.
1459 ControllingExpr = ControllingExpr->IgnoreParens();
1460 Diag(ControllingExpr->getLocStart(), diag::err_generic_sel_multi_match)
1461 << ControllingExpr->getSourceRange() << ControllingExpr->getType()
1462 << (unsigned) CompatIndices.size();
1463 for (unsigned I : CompatIndices) {
1464 Diag(Types[I]->getTypeLoc().getBeginLoc(),
1465 diag::note_compat_assoc)
1466 << Types[I]->getTypeLoc().getSourceRange()
1467 << Types[I]->getType();
1468 }
1469 return ExprError();
1470 }
1471
1472 // C11 6.5.1.1p2 "If a generic selection has no default generic association,
1473 // its controlling expression shall have type compatible with exactly one of
1474 // the types named in its generic association list."
1475 if (DefaultIndex == -1U && CompatIndices.size() == 0) {
1476 // We strip parens here because the controlling expression is typically
1477 // parenthesized in macro definitions.
1478 ControllingExpr = ControllingExpr->IgnoreParens();
1479 Diag(ControllingExpr->getLocStart(), diag::err_generic_sel_no_match)
1480 << ControllingExpr->getSourceRange() << ControllingExpr->getType();
1481 return ExprError();
1482 }
1483
1484 // C11 6.5.1.1p3 "If a generic selection has a generic association with a
1485 // type name that is compatible with the type of the controlling expression,
1486 // then the result expression of the generic selection is the expression
1487 // in that generic association. Otherwise, the result expression of the
1488 // generic selection is the expression in the default generic association."
1489 unsigned ResultIndex =
1490 CompatIndices.size() ? CompatIndices[0] : DefaultIndex;
1491
1492 return new (Context) GenericSelectionExpr(
1493 Context, KeyLoc, ControllingExpr, Types, Exprs, DefaultLoc, RParenLoc,
1494 ContainsUnexpandedParameterPack, ResultIndex);
1495 }
1496
1497 /// getUDSuffixLoc - Create a SourceLocation for a ud-suffix, given the
1498 /// location of the token and the offset of the ud-suffix within it.
getUDSuffixLoc(Sema & S,SourceLocation TokLoc,unsigned Offset)1499 static SourceLocation getUDSuffixLoc(Sema &S, SourceLocation TokLoc,
1500 unsigned Offset) {
1501 return Lexer::AdvanceToTokenCharacter(TokLoc, Offset, S.getSourceManager(),
1502 S.getLangOpts());
1503 }
1504
1505 /// BuildCookedLiteralOperatorCall - A user-defined literal was found. Look up
1506 /// the corresponding cooked (non-raw) literal operator, and build a call to it.
BuildCookedLiteralOperatorCall(Sema & S,Scope * Scope,IdentifierInfo * UDSuffix,SourceLocation UDSuffixLoc,ArrayRef<Expr * > Args,SourceLocation LitEndLoc)1507 static ExprResult BuildCookedLiteralOperatorCall(Sema &S, Scope *Scope,
1508 IdentifierInfo *UDSuffix,
1509 SourceLocation UDSuffixLoc,
1510 ArrayRef<Expr*> Args,
1511 SourceLocation LitEndLoc) {
1512 assert(Args.size() <= 2 && "too many arguments for literal operator");
1513
1514 QualType ArgTy[2];
1515 for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) {
1516 ArgTy[ArgIdx] = Args[ArgIdx]->getType();
1517 if (ArgTy[ArgIdx]->isArrayType())
1518 ArgTy[ArgIdx] = S.Context.getArrayDecayedType(ArgTy[ArgIdx]);
1519 }
1520
1521 DeclarationName OpName =
1522 S.Context.DeclarationNames.getCXXLiteralOperatorName(UDSuffix);
1523 DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc);
1524 OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc);
1525
1526 LookupResult R(S, OpName, UDSuffixLoc, Sema::LookupOrdinaryName);
1527 if (S.LookupLiteralOperator(Scope, R, llvm::makeArrayRef(ArgTy, Args.size()),
1528 /*AllowRaw*/false, /*AllowTemplate*/false,
1529 /*AllowStringTemplate*/false) == Sema::LOLR_Error)
1530 return ExprError();
1531
1532 return S.BuildLiteralOperatorCall(R, OpNameInfo, Args, LitEndLoc);
1533 }
1534
1535 /// ActOnStringLiteral - The specified tokens were lexed as pasted string
1536 /// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string
1537 /// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from
1538 /// multiple tokens. However, the common case is that StringToks points to one
1539 /// string.
1540 ///
1541 ExprResult
ActOnStringLiteral(ArrayRef<Token> StringToks,Scope * UDLScope)1542 Sema::ActOnStringLiteral(ArrayRef<Token> StringToks, Scope *UDLScope) {
1543 assert(!StringToks.empty() && "Must have at least one string!");
1544
1545 StringLiteralParser Literal(StringToks, PP);
1546 if (Literal.hadError)
1547 return ExprError();
1548
1549 SmallVector<SourceLocation, 4> StringTokLocs;
1550 for (const Token &Tok : StringToks)
1551 StringTokLocs.push_back(Tok.getLocation());
1552
1553 QualType CharTy = Context.CharTy;
1554 StringLiteral::StringKind Kind = StringLiteral::Ascii;
1555 if (Literal.isWide()) {
1556 CharTy = Context.getWideCharType();
1557 Kind = StringLiteral::Wide;
1558 } else if (Literal.isUTF8()) {
1559 Kind = StringLiteral::UTF8;
1560 } else if (Literal.isUTF16()) {
1561 CharTy = Context.Char16Ty;
1562 Kind = StringLiteral::UTF16;
1563 } else if (Literal.isUTF32()) {
1564 CharTy = Context.Char32Ty;
1565 Kind = StringLiteral::UTF32;
1566 } else if (Literal.isPascal()) {
1567 CharTy = Context.UnsignedCharTy;
1568 }
1569
1570 QualType CharTyConst = CharTy;
1571 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1).
1572 if (getLangOpts().CPlusPlus || getLangOpts().ConstStrings)
1573 CharTyConst.addConst();
1574
1575 // Get an array type for the string, according to C99 6.4.5. This includes
1576 // the nul terminator character as well as the string length for pascal
1577 // strings.
1578 QualType StrTy = Context.getConstantArrayType(CharTyConst,
1579 llvm::APInt(32, Literal.GetNumStringChars()+1),
1580 ArrayType::Normal, 0);
1581
1582 // OpenCL v1.1 s6.5.3: a string literal is in the constant address space.
1583 if (getLangOpts().OpenCL) {
1584 StrTy = Context.getAddrSpaceQualType(StrTy, LangAS::opencl_constant);
1585 }
1586
1587 // Pass &StringTokLocs[0], StringTokLocs.size() to factory!
1588 StringLiteral *Lit = StringLiteral::Create(Context, Literal.GetString(),
1589 Kind, Literal.Pascal, StrTy,
1590 &StringTokLocs[0],
1591 StringTokLocs.size());
1592 if (Literal.getUDSuffix().empty())
1593 return Lit;
1594
1595 // We're building a user-defined literal.
1596 IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix());
1597 SourceLocation UDSuffixLoc =
1598 getUDSuffixLoc(*this, StringTokLocs[Literal.getUDSuffixToken()],
1599 Literal.getUDSuffixOffset());
1600
1601 // Make sure we're allowed user-defined literals here.
1602 if (!UDLScope)
1603 return ExprError(Diag(UDSuffixLoc, diag::err_invalid_string_udl));
1604
1605 // C++11 [lex.ext]p5: The literal L is treated as a call of the form
1606 // operator "" X (str, len)
1607 QualType SizeType = Context.getSizeType();
1608
1609 DeclarationName OpName =
1610 Context.DeclarationNames.getCXXLiteralOperatorName(UDSuffix);
1611 DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc);
1612 OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc);
1613
1614 QualType ArgTy[] = {
1615 Context.getArrayDecayedType(StrTy), SizeType
1616 };
1617
1618 LookupResult R(*this, OpName, UDSuffixLoc, LookupOrdinaryName);
1619 switch (LookupLiteralOperator(UDLScope, R, ArgTy,
1620 /*AllowRaw*/false, /*AllowTemplate*/false,
1621 /*AllowStringTemplate*/true)) {
1622
1623 case LOLR_Cooked: {
1624 llvm::APInt Len(Context.getIntWidth(SizeType), Literal.GetNumStringChars());
1625 IntegerLiteral *LenArg = IntegerLiteral::Create(Context, Len, SizeType,
1626 StringTokLocs[0]);
1627 Expr *Args[] = { Lit, LenArg };
1628
1629 return BuildLiteralOperatorCall(R, OpNameInfo, Args, StringTokLocs.back());
1630 }
1631
1632 case LOLR_StringTemplate: {
1633 TemplateArgumentListInfo ExplicitArgs;
1634
1635 unsigned CharBits = Context.getIntWidth(CharTy);
1636 bool CharIsUnsigned = CharTy->isUnsignedIntegerType();
1637 llvm::APSInt Value(CharBits, CharIsUnsigned);
1638
1639 TemplateArgument TypeArg(CharTy);
1640 TemplateArgumentLocInfo TypeArgInfo(Context.getTrivialTypeSourceInfo(CharTy));
1641 ExplicitArgs.addArgument(TemplateArgumentLoc(TypeArg, TypeArgInfo));
1642
1643 for (unsigned I = 0, N = Lit->getLength(); I != N; ++I) {
1644 Value = Lit->getCodeUnit(I);
1645 TemplateArgument Arg(Context, Value, CharTy);
1646 TemplateArgumentLocInfo ArgInfo;
1647 ExplicitArgs.addArgument(TemplateArgumentLoc(Arg, ArgInfo));
1648 }
1649 return BuildLiteralOperatorCall(R, OpNameInfo, None, StringTokLocs.back(),
1650 &ExplicitArgs);
1651 }
1652 case LOLR_Raw:
1653 case LOLR_Template:
1654 llvm_unreachable("unexpected literal operator lookup result");
1655 case LOLR_Error:
1656 return ExprError();
1657 }
1658 llvm_unreachable("unexpected literal operator lookup result");
1659 }
1660
1661 ExprResult
BuildDeclRefExpr(ValueDecl * D,QualType Ty,ExprValueKind VK,SourceLocation Loc,const CXXScopeSpec * SS)1662 Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
1663 SourceLocation Loc,
1664 const CXXScopeSpec *SS) {
1665 DeclarationNameInfo NameInfo(D->getDeclName(), Loc);
1666 return BuildDeclRefExpr(D, Ty, VK, NameInfo, SS);
1667 }
1668
1669 /// BuildDeclRefExpr - Build an expression that references a
1670 /// declaration that does not require a closure capture.
1671 ExprResult
BuildDeclRefExpr(ValueDecl * D,QualType Ty,ExprValueKind VK,const DeclarationNameInfo & NameInfo,const CXXScopeSpec * SS,NamedDecl * FoundD,const TemplateArgumentListInfo * TemplateArgs)1672 Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
1673 const DeclarationNameInfo &NameInfo,
1674 const CXXScopeSpec *SS, NamedDecl *FoundD,
1675 const TemplateArgumentListInfo *TemplateArgs) {
1676 if (getLangOpts().CUDA)
1677 if (const FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext))
1678 if (const FunctionDecl *Callee = dyn_cast<FunctionDecl>(D)) {
1679 if (CheckCUDATarget(Caller, Callee)) {
1680 Diag(NameInfo.getLoc(), diag::err_ref_bad_target)
1681 << IdentifyCUDATarget(Callee) << D->getIdentifier()
1682 << IdentifyCUDATarget(Caller);
1683 Diag(D->getLocation(), diag::note_previous_decl)
1684 << D->getIdentifier();
1685 return ExprError();
1686 }
1687 }
1688
1689 bool RefersToCapturedVariable =
1690 isa<VarDecl>(D) &&
1691 NeedToCaptureVariable(cast<VarDecl>(D), NameInfo.getLoc());
1692
1693 DeclRefExpr *E;
1694 if (isa<VarTemplateSpecializationDecl>(D)) {
1695 VarTemplateSpecializationDecl *VarSpec =
1696 cast<VarTemplateSpecializationDecl>(D);
1697
1698 E = DeclRefExpr::Create(Context, SS ? SS->getWithLocInContext(Context)
1699 : NestedNameSpecifierLoc(),
1700 VarSpec->getTemplateKeywordLoc(), D,
1701 RefersToCapturedVariable, NameInfo.getLoc(), Ty, VK,
1702 FoundD, TemplateArgs);
1703 } else {
1704 assert(!TemplateArgs && "No template arguments for non-variable"
1705 " template specialization references");
1706 E = DeclRefExpr::Create(Context, SS ? SS->getWithLocInContext(Context)
1707 : NestedNameSpecifierLoc(),
1708 SourceLocation(), D, RefersToCapturedVariable,
1709 NameInfo, Ty, VK, FoundD);
1710 }
1711
1712 MarkDeclRefReferenced(E);
1713
1714 if (getLangOpts().ObjCWeak && isa<VarDecl>(D) &&
1715 Ty.getObjCLifetime() == Qualifiers::OCL_Weak &&
1716 !Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, E->getLocStart()))
1717 recordUseOfEvaluatedWeak(E);
1718
1719 // Just in case we're building an illegal pointer-to-member.
1720 FieldDecl *FD = dyn_cast<FieldDecl>(D);
1721 if (FD && FD->isBitField())
1722 E->setObjectKind(OK_BitField);
1723
1724 return E;
1725 }
1726
1727 /// Decomposes the given name into a DeclarationNameInfo, its location, and
1728 /// possibly a list of template arguments.
1729 ///
1730 /// If this produces template arguments, it is permitted to call
1731 /// DecomposeTemplateName.
1732 ///
1733 /// This actually loses a lot of source location information for
1734 /// non-standard name kinds; we should consider preserving that in
1735 /// some way.
1736 void
DecomposeUnqualifiedId(const UnqualifiedId & Id,TemplateArgumentListInfo & Buffer,DeclarationNameInfo & NameInfo,const TemplateArgumentListInfo * & TemplateArgs)1737 Sema::DecomposeUnqualifiedId(const UnqualifiedId &Id,
1738 TemplateArgumentListInfo &Buffer,
1739 DeclarationNameInfo &NameInfo,
1740 const TemplateArgumentListInfo *&TemplateArgs) {
1741 if (Id.getKind() == UnqualifiedId::IK_TemplateId) {
1742 Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc);
1743 Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc);
1744
1745 ASTTemplateArgsPtr TemplateArgsPtr(Id.TemplateId->getTemplateArgs(),
1746 Id.TemplateId->NumArgs);
1747 translateTemplateArguments(TemplateArgsPtr, Buffer);
1748
1749 TemplateName TName = Id.TemplateId->Template.get();
1750 SourceLocation TNameLoc = Id.TemplateId->TemplateNameLoc;
1751 NameInfo = Context.getNameForTemplate(TName, TNameLoc);
1752 TemplateArgs = &Buffer;
1753 } else {
1754 NameInfo = GetNameFromUnqualifiedId(Id);
1755 TemplateArgs = nullptr;
1756 }
1757 }
1758
emitEmptyLookupTypoDiagnostic(const TypoCorrection & TC,Sema & SemaRef,const CXXScopeSpec & SS,DeclarationName Typo,SourceLocation TypoLoc,ArrayRef<Expr * > Args,unsigned DiagnosticID,unsigned DiagnosticSuggestID)1759 static void emitEmptyLookupTypoDiagnostic(
1760 const TypoCorrection &TC, Sema &SemaRef, const CXXScopeSpec &SS,
1761 DeclarationName Typo, SourceLocation TypoLoc, ArrayRef<Expr *> Args,
1762 unsigned DiagnosticID, unsigned DiagnosticSuggestID) {
1763 DeclContext *Ctx =
1764 SS.isEmpty() ? nullptr : SemaRef.computeDeclContext(SS, false);
1765 if (!TC) {
1766 // Emit a special diagnostic for failed member lookups.
1767 // FIXME: computing the declaration context might fail here (?)
1768 if (Ctx)
1769 SemaRef.Diag(TypoLoc, diag::err_no_member) << Typo << Ctx
1770 << SS.getRange();
1771 else
1772 SemaRef.Diag(TypoLoc, DiagnosticID) << Typo;
1773 return;
1774 }
1775
1776 std::string CorrectedStr = TC.getAsString(SemaRef.getLangOpts());
1777 bool DroppedSpecifier =
1778 TC.WillReplaceSpecifier() && Typo.getAsString() == CorrectedStr;
1779 unsigned NoteID =
1780 (TC.getCorrectionDecl() && isa<ImplicitParamDecl>(TC.getCorrectionDecl()))
1781 ? diag::note_implicit_param_decl
1782 : diag::note_previous_decl;
1783 if (!Ctx)
1784 SemaRef.diagnoseTypo(TC, SemaRef.PDiag(DiagnosticSuggestID) << Typo,
1785 SemaRef.PDiag(NoteID));
1786 else
1787 SemaRef.diagnoseTypo(TC, SemaRef.PDiag(diag::err_no_member_suggest)
1788 << Typo << Ctx << DroppedSpecifier
1789 << SS.getRange(),
1790 SemaRef.PDiag(NoteID));
1791 }
1792
1793 /// Diagnose an empty lookup.
1794 ///
1795 /// \return false if new lookup candidates were found
1796 bool
DiagnoseEmptyLookup(Scope * S,CXXScopeSpec & SS,LookupResult & R,std::unique_ptr<CorrectionCandidateCallback> CCC,TemplateArgumentListInfo * ExplicitTemplateArgs,ArrayRef<Expr * > Args,TypoExpr ** Out)1797 Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R,
1798 std::unique_ptr<CorrectionCandidateCallback> CCC,
1799 TemplateArgumentListInfo *ExplicitTemplateArgs,
1800 ArrayRef<Expr *> Args, TypoExpr **Out) {
1801 DeclarationName Name = R.getLookupName();
1802
1803 unsigned diagnostic = diag::err_undeclared_var_use;
1804 unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest;
1805 if (Name.getNameKind() == DeclarationName::CXXOperatorName ||
1806 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName ||
1807 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) {
1808 diagnostic = diag::err_undeclared_use;
1809 diagnostic_suggest = diag::err_undeclared_use_suggest;
1810 }
1811
1812 // If the original lookup was an unqualified lookup, fake an
1813 // unqualified lookup. This is useful when (for example) the
1814 // original lookup would not have found something because it was a
1815 // dependent name.
1816 DeclContext *DC = SS.isEmpty() ? CurContext : nullptr;
1817 while (DC) {
1818 if (isa<CXXRecordDecl>(DC)) {
1819 LookupQualifiedName(R, DC);
1820
1821 if (!R.empty()) {
1822 // Don't give errors about ambiguities in this lookup.
1823 R.suppressDiagnostics();
1824
1825 // During a default argument instantiation the CurContext points
1826 // to a CXXMethodDecl; but we can't apply a this-> fixit inside a
1827 // function parameter list, hence add an explicit check.
1828 bool isDefaultArgument = !ActiveTemplateInstantiations.empty() &&
1829 ActiveTemplateInstantiations.back().Kind ==
1830 ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation;
1831 CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext);
1832 bool isInstance = CurMethod &&
1833 CurMethod->isInstance() &&
1834 DC == CurMethod->getParent() && !isDefaultArgument;
1835
1836 // Give a code modification hint to insert 'this->'.
1837 // TODO: fixit for inserting 'Base<T>::' in the other cases.
1838 // Actually quite difficult!
1839 if (getLangOpts().MSVCCompat)
1840 diagnostic = diag::ext_found_via_dependent_bases_lookup;
1841 if (isInstance) {
1842 Diag(R.getNameLoc(), diagnostic) << Name
1843 << FixItHint::CreateInsertion(R.getNameLoc(), "this->");
1844 CheckCXXThisCapture(R.getNameLoc());
1845 } else {
1846 Diag(R.getNameLoc(), diagnostic) << Name;
1847 }
1848
1849 // Do we really want to note all of these?
1850 for (NamedDecl *D : R)
1851 Diag(D->getLocation(), diag::note_dependent_var_use);
1852
1853 // Return true if we are inside a default argument instantiation
1854 // and the found name refers to an instance member function, otherwise
1855 // the function calling DiagnoseEmptyLookup will try to create an
1856 // implicit member call and this is wrong for default argument.
1857 if (isDefaultArgument && ((*R.begin())->isCXXInstanceMember())) {
1858 Diag(R.getNameLoc(), diag::err_member_call_without_object);
1859 return true;
1860 }
1861
1862 // Tell the callee to try to recover.
1863 return false;
1864 }
1865
1866 R.clear();
1867 }
1868
1869 // In Microsoft mode, if we are performing lookup from within a friend
1870 // function definition declared at class scope then we must set
1871 // DC to the lexical parent to be able to search into the parent
1872 // class.
1873 if (getLangOpts().MSVCCompat && isa<FunctionDecl>(DC) &&
1874 cast<FunctionDecl>(DC)->getFriendObjectKind() &&
1875 DC->getLexicalParent()->isRecord())
1876 DC = DC->getLexicalParent();
1877 else
1878 DC = DC->getParent();
1879 }
1880
1881 // We didn't find anything, so try to correct for a typo.
1882 TypoCorrection Corrected;
1883 if (S && Out) {
1884 SourceLocation TypoLoc = R.getNameLoc();
1885 assert(!ExplicitTemplateArgs &&
1886 "Diagnosing an empty lookup with explicit template args!");
1887 *Out = CorrectTypoDelayed(
1888 R.getLookupNameInfo(), R.getLookupKind(), S, &SS, std::move(CCC),
1889 [=](const TypoCorrection &TC) {
1890 emitEmptyLookupTypoDiagnostic(TC, *this, SS, Name, TypoLoc, Args,
1891 diagnostic, diagnostic_suggest);
1892 },
1893 nullptr, CTK_ErrorRecovery);
1894 if (*Out)
1895 return true;
1896 } else if (S && (Corrected =
1897 CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(), S,
1898 &SS, std::move(CCC), CTK_ErrorRecovery))) {
1899 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
1900 bool DroppedSpecifier =
1901 Corrected.WillReplaceSpecifier() && Name.getAsString() == CorrectedStr;
1902 R.setLookupName(Corrected.getCorrection());
1903
1904 bool AcceptableWithRecovery = false;
1905 bool AcceptableWithoutRecovery = false;
1906 NamedDecl *ND = Corrected.getCorrectionDecl();
1907 if (ND) {
1908 if (Corrected.isOverloaded()) {
1909 OverloadCandidateSet OCS(R.getNameLoc(),
1910 OverloadCandidateSet::CSK_Normal);
1911 OverloadCandidateSet::iterator Best;
1912 for (NamedDecl *CD : Corrected) {
1913 if (FunctionTemplateDecl *FTD =
1914 dyn_cast<FunctionTemplateDecl>(CD))
1915 AddTemplateOverloadCandidate(
1916 FTD, DeclAccessPair::make(FTD, AS_none), ExplicitTemplateArgs,
1917 Args, OCS);
1918 else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(CD))
1919 if (!ExplicitTemplateArgs || ExplicitTemplateArgs->size() == 0)
1920 AddOverloadCandidate(FD, DeclAccessPair::make(FD, AS_none),
1921 Args, OCS);
1922 }
1923 switch (OCS.BestViableFunction(*this, R.getNameLoc(), Best)) {
1924 case OR_Success:
1925 ND = Best->Function;
1926 Corrected.setCorrectionDecl(ND);
1927 break;
1928 default:
1929 // FIXME: Arbitrarily pick the first declaration for the note.
1930 Corrected.setCorrectionDecl(ND);
1931 break;
1932 }
1933 }
1934 R.addDecl(ND);
1935 if (getLangOpts().CPlusPlus && ND->isCXXClassMember()) {
1936 CXXRecordDecl *Record = nullptr;
1937 if (Corrected.getCorrectionSpecifier()) {
1938 const Type *Ty = Corrected.getCorrectionSpecifier()->getAsType();
1939 Record = Ty->getAsCXXRecordDecl();
1940 }
1941 if (!Record)
1942 Record = cast<CXXRecordDecl>(
1943 ND->getDeclContext()->getRedeclContext());
1944 R.setNamingClass(Record);
1945 }
1946
1947 AcceptableWithRecovery =
1948 isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND);
1949 // FIXME: If we ended up with a typo for a type name or
1950 // Objective-C class name, we're in trouble because the parser
1951 // is in the wrong place to recover. Suggest the typo
1952 // correction, but don't make it a fix-it since we're not going
1953 // to recover well anyway.
1954 AcceptableWithoutRecovery =
1955 isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND);
1956 } else {
1957 // FIXME: We found a keyword. Suggest it, but don't provide a fix-it
1958 // because we aren't able to recover.
1959 AcceptableWithoutRecovery = true;
1960 }
1961
1962 if (AcceptableWithRecovery || AcceptableWithoutRecovery) {
1963 unsigned NoteID = (Corrected.getCorrectionDecl() &&
1964 isa<ImplicitParamDecl>(Corrected.getCorrectionDecl()))
1965 ? diag::note_implicit_param_decl
1966 : diag::note_previous_decl;
1967 if (SS.isEmpty())
1968 diagnoseTypo(Corrected, PDiag(diagnostic_suggest) << Name,
1969 PDiag(NoteID), AcceptableWithRecovery);
1970 else
1971 diagnoseTypo(Corrected, PDiag(diag::err_no_member_suggest)
1972 << Name << computeDeclContext(SS, false)
1973 << DroppedSpecifier << SS.getRange(),
1974 PDiag(NoteID), AcceptableWithRecovery);
1975
1976 // Tell the callee whether to try to recover.
1977 return !AcceptableWithRecovery;
1978 }
1979 }
1980 R.clear();
1981
1982 // Emit a special diagnostic for failed member lookups.
1983 // FIXME: computing the declaration context might fail here (?)
1984 if (!SS.isEmpty()) {
1985 Diag(R.getNameLoc(), diag::err_no_member)
1986 << Name << computeDeclContext(SS, false)
1987 << SS.getRange();
1988 return true;
1989 }
1990
1991 // Give up, we can't recover.
1992 Diag(R.getNameLoc(), diagnostic) << Name;
1993 return true;
1994 }
1995
1996 /// In Microsoft mode, if we are inside a template class whose parent class has
1997 /// dependent base classes, and we can't resolve an unqualified identifier, then
1998 /// assume the identifier is a member of a dependent base class. We can only
1999 /// recover successfully in static methods, instance methods, and other contexts
2000 /// where 'this' is available. This doesn't precisely match MSVC's
2001 /// instantiation model, but it's close enough.
2002 static Expr *
recoverFromMSUnqualifiedLookup(Sema & S,ASTContext & Context,DeclarationNameInfo & NameInfo,SourceLocation TemplateKWLoc,const TemplateArgumentListInfo * TemplateArgs)2003 recoverFromMSUnqualifiedLookup(Sema &S, ASTContext &Context,
2004 DeclarationNameInfo &NameInfo,
2005 SourceLocation TemplateKWLoc,
2006 const TemplateArgumentListInfo *TemplateArgs) {
2007 // Only try to recover from lookup into dependent bases in static methods or
2008 // contexts where 'this' is available.
2009 QualType ThisType = S.getCurrentThisType();
2010 const CXXRecordDecl *RD = nullptr;
2011 if (!ThisType.isNull())
2012 RD = ThisType->getPointeeType()->getAsCXXRecordDecl();
2013 else if (auto *MD = dyn_cast<CXXMethodDecl>(S.CurContext))
2014 RD = MD->getParent();
2015 if (!RD || !RD->hasAnyDependentBases())
2016 return nullptr;
2017
2018 // Diagnose this as unqualified lookup into a dependent base class. If 'this'
2019 // is available, suggest inserting 'this->' as a fixit.
2020 SourceLocation Loc = NameInfo.getLoc();
2021 auto DB = S.Diag(Loc, diag::ext_undeclared_unqual_id_with_dependent_base);
2022 DB << NameInfo.getName() << RD;
2023
2024 if (!ThisType.isNull()) {
2025 DB << FixItHint::CreateInsertion(Loc, "this->");
2026 return CXXDependentScopeMemberExpr::Create(
2027 Context, /*This=*/nullptr, ThisType, /*IsArrow=*/true,
2028 /*Op=*/SourceLocation(), NestedNameSpecifierLoc(), TemplateKWLoc,
2029 /*FirstQualifierInScope=*/nullptr, NameInfo, TemplateArgs);
2030 }
2031
2032 // Synthesize a fake NNS that points to the derived class. This will
2033 // perform name lookup during template instantiation.
2034 CXXScopeSpec SS;
2035 auto *NNS =
2036 NestedNameSpecifier::Create(Context, nullptr, true, RD->getTypeForDecl());
2037 SS.MakeTrivial(Context, NNS, SourceRange(Loc, Loc));
2038 return DependentScopeDeclRefExpr::Create(
2039 Context, SS.getWithLocInContext(Context), TemplateKWLoc, NameInfo,
2040 TemplateArgs);
2041 }
2042
2043 ExprResult
ActOnIdExpression(Scope * S,CXXScopeSpec & SS,SourceLocation TemplateKWLoc,UnqualifiedId & Id,bool HasTrailingLParen,bool IsAddressOfOperand,std::unique_ptr<CorrectionCandidateCallback> CCC,bool IsInlineAsmIdentifier,Token * KeywordReplacement)2044 Sema::ActOnIdExpression(Scope *S, CXXScopeSpec &SS,
2045 SourceLocation TemplateKWLoc, UnqualifiedId &Id,
2046 bool HasTrailingLParen, bool IsAddressOfOperand,
2047 std::unique_ptr<CorrectionCandidateCallback> CCC,
2048 bool IsInlineAsmIdentifier, Token *KeywordReplacement) {
2049 assert(!(IsAddressOfOperand && HasTrailingLParen) &&
2050 "cannot be direct & operand and have a trailing lparen");
2051 if (SS.isInvalid())
2052 return ExprError();
2053
2054 TemplateArgumentListInfo TemplateArgsBuffer;
2055
2056 // Decompose the UnqualifiedId into the following data.
2057 DeclarationNameInfo NameInfo;
2058 const TemplateArgumentListInfo *TemplateArgs;
2059 DecomposeUnqualifiedId(Id, TemplateArgsBuffer, NameInfo, TemplateArgs);
2060
2061 DeclarationName Name = NameInfo.getName();
2062 IdentifierInfo *II = Name.getAsIdentifierInfo();
2063 SourceLocation NameLoc = NameInfo.getLoc();
2064
2065 // C++ [temp.dep.expr]p3:
2066 // An id-expression is type-dependent if it contains:
2067 // -- an identifier that was declared with a dependent type,
2068 // (note: handled after lookup)
2069 // -- a template-id that is dependent,
2070 // (note: handled in BuildTemplateIdExpr)
2071 // -- a conversion-function-id that specifies a dependent type,
2072 // -- a nested-name-specifier that contains a class-name that
2073 // names a dependent type.
2074 // Determine whether this is a member of an unknown specialization;
2075 // we need to handle these differently.
2076 bool DependentID = false;
2077 if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName &&
2078 Name.getCXXNameType()->isDependentType()) {
2079 DependentID = true;
2080 } else if (SS.isSet()) {
2081 if (DeclContext *DC = computeDeclContext(SS, false)) {
2082 if (RequireCompleteDeclContext(SS, DC))
2083 return ExprError();
2084 } else {
2085 DependentID = true;
2086 }
2087 }
2088
2089 if (DependentID)
2090 return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo,
2091 IsAddressOfOperand, TemplateArgs);
2092
2093 // Perform the required lookup.
2094 LookupResult R(*this, NameInfo,
2095 (Id.getKind() == UnqualifiedId::IK_ImplicitSelfParam)
2096 ? LookupObjCImplicitSelfParam : LookupOrdinaryName);
2097 if (TemplateArgs) {
2098 // Lookup the template name again to correctly establish the context in
2099 // which it was found. This is really unfortunate as we already did the
2100 // lookup to determine that it was a template name in the first place. If
2101 // this becomes a performance hit, we can work harder to preserve those
2102 // results until we get here but it's likely not worth it.
2103 bool MemberOfUnknownSpecialization;
2104 LookupTemplateName(R, S, SS, QualType(), /*EnteringContext=*/false,
2105 MemberOfUnknownSpecialization);
2106
2107 if (MemberOfUnknownSpecialization ||
2108 (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation))
2109 return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo,
2110 IsAddressOfOperand, TemplateArgs);
2111 } else {
2112 bool IvarLookupFollowUp = II && !SS.isSet() && getCurMethodDecl();
2113 LookupParsedName(R, S, &SS, !IvarLookupFollowUp);
2114
2115 // If the result might be in a dependent base class, this is a dependent
2116 // id-expression.
2117 if (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation)
2118 return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo,
2119 IsAddressOfOperand, TemplateArgs);
2120
2121 // If this reference is in an Objective-C method, then we need to do
2122 // some special Objective-C lookup, too.
2123 if (IvarLookupFollowUp) {
2124 ExprResult E(LookupInObjCMethod(R, S, II, true));
2125 if (E.isInvalid())
2126 return ExprError();
2127
2128 if (Expr *Ex = E.getAs<Expr>())
2129 return Ex;
2130 }
2131 }
2132
2133 if (R.isAmbiguous())
2134 return ExprError();
2135
2136 // This could be an implicitly declared function reference (legal in C90,
2137 // extension in C99, forbidden in C++).
2138 if (R.empty() && HasTrailingLParen && II && !getLangOpts().CPlusPlus) {
2139 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S);
2140 if (D) R.addDecl(D);
2141 }
2142
2143 // Determine whether this name might be a candidate for
2144 // argument-dependent lookup.
2145 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen);
2146
2147 if (R.empty() && !ADL) {
2148 if (SS.isEmpty() && getLangOpts().MSVCCompat) {
2149 if (Expr *E = recoverFromMSUnqualifiedLookup(*this, Context, NameInfo,
2150 TemplateKWLoc, TemplateArgs))
2151 return E;
2152 }
2153
2154 // Don't diagnose an empty lookup for inline assembly.
2155 if (IsInlineAsmIdentifier)
2156 return ExprError();
2157
2158 // If this name wasn't predeclared and if this is not a function
2159 // call, diagnose the problem.
2160 TypoExpr *TE = nullptr;
2161 auto DefaultValidator = llvm::make_unique<CorrectionCandidateCallback>(
2162 II, SS.isValid() ? SS.getScopeRep() : nullptr);
2163 DefaultValidator->IsAddressOfOperand = IsAddressOfOperand;
2164 assert((!CCC || CCC->IsAddressOfOperand == IsAddressOfOperand) &&
2165 "Typo correction callback misconfigured");
2166 if (CCC) {
2167 // Make sure the callback knows what the typo being diagnosed is.
2168 CCC->setTypoName(II);
2169 if (SS.isValid())
2170 CCC->setTypoNNS(SS.getScopeRep());
2171 }
2172 if (DiagnoseEmptyLookup(S, SS, R,
2173 CCC ? std::move(CCC) : std::move(DefaultValidator),
2174 nullptr, None, &TE)) {
2175 if (TE && KeywordReplacement) {
2176 auto &State = getTypoExprState(TE);
2177 auto BestTC = State.Consumer->getNextCorrection();
2178 if (BestTC.isKeyword()) {
2179 auto *II = BestTC.getCorrectionAsIdentifierInfo();
2180 if (State.DiagHandler)
2181 State.DiagHandler(BestTC);
2182 KeywordReplacement->startToken();
2183 KeywordReplacement->setKind(II->getTokenID());
2184 KeywordReplacement->setIdentifierInfo(II);
2185 KeywordReplacement->setLocation(BestTC.getCorrectionRange().getBegin());
2186 // Clean up the state associated with the TypoExpr, since it has
2187 // now been diagnosed (without a call to CorrectDelayedTyposInExpr).
2188 clearDelayedTypo(TE);
2189 // Signal that a correction to a keyword was performed by returning a
2190 // valid-but-null ExprResult.
2191 return (Expr*)nullptr;
2192 }
2193 State.Consumer->resetCorrectionStream();
2194 }
2195 return TE ? TE : ExprError();
2196 }
2197
2198 assert(!R.empty() &&
2199 "DiagnoseEmptyLookup returned false but added no results");
2200
2201 // If we found an Objective-C instance variable, let
2202 // LookupInObjCMethod build the appropriate expression to
2203 // reference the ivar.
2204 if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) {
2205 R.clear();
2206 ExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier()));
2207 // In a hopelessly buggy code, Objective-C instance variable
2208 // lookup fails and no expression will be built to reference it.
2209 if (!E.isInvalid() && !E.get())
2210 return ExprError();
2211 return E;
2212 }
2213 }
2214
2215 // This is guaranteed from this point on.
2216 assert(!R.empty() || ADL);
2217
2218 // Check whether this might be a C++ implicit instance member access.
2219 // C++ [class.mfct.non-static]p3:
2220 // When an id-expression that is not part of a class member access
2221 // syntax and not used to form a pointer to member is used in the
2222 // body of a non-static member function of class X, if name lookup
2223 // resolves the name in the id-expression to a non-static non-type
2224 // member of some class C, the id-expression is transformed into a
2225 // class member access expression using (*this) as the
2226 // postfix-expression to the left of the . operator.
2227 //
2228 // But we don't actually need to do this for '&' operands if R
2229 // resolved to a function or overloaded function set, because the
2230 // expression is ill-formed if it actually works out to be a
2231 // non-static member function:
2232 //
2233 // C++ [expr.ref]p4:
2234 // Otherwise, if E1.E2 refers to a non-static member function. . .
2235 // [t]he expression can be used only as the left-hand operand of a
2236 // member function call.
2237 //
2238 // There are other safeguards against such uses, but it's important
2239 // to get this right here so that we don't end up making a
2240 // spuriously dependent expression if we're inside a dependent
2241 // instance method.
2242 if (!R.empty() && (*R.begin())->isCXXClassMember()) {
2243 bool MightBeImplicitMember;
2244 if (!IsAddressOfOperand)
2245 MightBeImplicitMember = true;
2246 else if (!SS.isEmpty())
2247 MightBeImplicitMember = false;
2248 else if (R.isOverloadedResult())
2249 MightBeImplicitMember = false;
2250 else if (R.isUnresolvableResult())
2251 MightBeImplicitMember = true;
2252 else
2253 MightBeImplicitMember = isa<FieldDecl>(R.getFoundDecl()) ||
2254 isa<IndirectFieldDecl>(R.getFoundDecl()) ||
2255 isa<MSPropertyDecl>(R.getFoundDecl());
2256
2257 if (MightBeImplicitMember)
2258 return BuildPossibleImplicitMemberExpr(SS, TemplateKWLoc,
2259 R, TemplateArgs, S);
2260 }
2261
2262 if (TemplateArgs || TemplateKWLoc.isValid()) {
2263
2264 // In C++1y, if this is a variable template id, then check it
2265 // in BuildTemplateIdExpr().
2266 // The single lookup result must be a variable template declaration.
2267 if (Id.getKind() == UnqualifiedId::IK_TemplateId && Id.TemplateId &&
2268 Id.TemplateId->Kind == TNK_Var_template) {
2269 assert(R.getAsSingle<VarTemplateDecl>() &&
2270 "There should only be one declaration found.");
2271 }
2272
2273 return BuildTemplateIdExpr(SS, TemplateKWLoc, R, ADL, TemplateArgs);
2274 }
2275
2276 return BuildDeclarationNameExpr(SS, R, ADL);
2277 }
2278
2279 /// BuildQualifiedDeclarationNameExpr - Build a C++ qualified
2280 /// declaration name, generally during template instantiation.
2281 /// There's a large number of things which don't need to be done along
2282 /// this path.
BuildQualifiedDeclarationNameExpr(CXXScopeSpec & SS,const DeclarationNameInfo & NameInfo,bool IsAddressOfOperand,const Scope * S,TypeSourceInfo ** RecoveryTSI)2283 ExprResult Sema::BuildQualifiedDeclarationNameExpr(
2284 CXXScopeSpec &SS, const DeclarationNameInfo &NameInfo,
2285 bool IsAddressOfOperand, const Scope *S, TypeSourceInfo **RecoveryTSI) {
2286 DeclContext *DC = computeDeclContext(SS, false);
2287 if (!DC)
2288 return BuildDependentDeclRefExpr(SS, /*TemplateKWLoc=*/SourceLocation(),
2289 NameInfo, /*TemplateArgs=*/nullptr);
2290
2291 if (RequireCompleteDeclContext(SS, DC))
2292 return ExprError();
2293
2294 LookupResult R(*this, NameInfo, LookupOrdinaryName);
2295 LookupQualifiedName(R, DC);
2296
2297 if (R.isAmbiguous())
2298 return ExprError();
2299
2300 if (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation)
2301 return BuildDependentDeclRefExpr(SS, /*TemplateKWLoc=*/SourceLocation(),
2302 NameInfo, /*TemplateArgs=*/nullptr);
2303
2304 if (R.empty()) {
2305 Diag(NameInfo.getLoc(), diag::err_no_member)
2306 << NameInfo.getName() << DC << SS.getRange();
2307 return ExprError();
2308 }
2309
2310 if (const TypeDecl *TD = R.getAsSingle<TypeDecl>()) {
2311 // Diagnose a missing typename if this resolved unambiguously to a type in
2312 // a dependent context. If we can recover with a type, downgrade this to
2313 // a warning in Microsoft compatibility mode.
2314 unsigned DiagID = diag::err_typename_missing;
2315 if (RecoveryTSI && getLangOpts().MSVCCompat)
2316 DiagID = diag::ext_typename_missing;
2317 SourceLocation Loc = SS.getBeginLoc();
2318 auto D = Diag(Loc, DiagID);
2319 D << SS.getScopeRep() << NameInfo.getName().getAsString()
2320 << SourceRange(Loc, NameInfo.getEndLoc());
2321
2322 // Don't recover if the caller isn't expecting us to or if we're in a SFINAE
2323 // context.
2324 if (!RecoveryTSI)
2325 return ExprError();
2326
2327 // Only issue the fixit if we're prepared to recover.
2328 D << FixItHint::CreateInsertion(Loc, "typename ");
2329
2330 // Recover by pretending this was an elaborated type.
2331 QualType Ty = Context.getTypeDeclType(TD);
2332 TypeLocBuilder TLB;
2333 TLB.pushTypeSpec(Ty).setNameLoc(NameInfo.getLoc());
2334
2335 QualType ET = getElaboratedType(ETK_None, SS, Ty);
2336 ElaboratedTypeLoc QTL = TLB.push<ElaboratedTypeLoc>(ET);
2337 QTL.setElaboratedKeywordLoc(SourceLocation());
2338 QTL.setQualifierLoc(SS.getWithLocInContext(Context));
2339
2340 *RecoveryTSI = TLB.getTypeSourceInfo(Context, ET);
2341
2342 return ExprEmpty();
2343 }
2344
2345 // Defend against this resolving to an implicit member access. We usually
2346 // won't get here if this might be a legitimate a class member (we end up in
2347 // BuildMemberReferenceExpr instead), but this can be valid if we're forming
2348 // a pointer-to-member or in an unevaluated context in C++11.
2349 if (!R.empty() && (*R.begin())->isCXXClassMember() && !IsAddressOfOperand)
2350 return BuildPossibleImplicitMemberExpr(SS,
2351 /*TemplateKWLoc=*/SourceLocation(),
2352 R, /*TemplateArgs=*/nullptr, S);
2353
2354 return BuildDeclarationNameExpr(SS, R, /* ADL */ false);
2355 }
2356
2357 /// LookupInObjCMethod - The parser has read a name in, and Sema has
2358 /// detected that we're currently inside an ObjC method. Perform some
2359 /// additional lookup.
2360 ///
2361 /// Ideally, most of this would be done by lookup, but there's
2362 /// actually quite a lot of extra work involved.
2363 ///
2364 /// Returns a null sentinel to indicate trivial success.
2365 ExprResult
LookupInObjCMethod(LookupResult & Lookup,Scope * S,IdentifierInfo * II,bool AllowBuiltinCreation)2366 Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S,
2367 IdentifierInfo *II, bool AllowBuiltinCreation) {
2368 SourceLocation Loc = Lookup.getNameLoc();
2369 ObjCMethodDecl *CurMethod = getCurMethodDecl();
2370
2371 // Check for error condition which is already reported.
2372 if (!CurMethod)
2373 return ExprError();
2374
2375 // There are two cases to handle here. 1) scoped lookup could have failed,
2376 // in which case we should look for an ivar. 2) scoped lookup could have
2377 // found a decl, but that decl is outside the current instance method (i.e.
2378 // a global variable). In these two cases, we do a lookup for an ivar with
2379 // this name, if the lookup sucedes, we replace it our current decl.
2380
2381 // If we're in a class method, we don't normally want to look for
2382 // ivars. But if we don't find anything else, and there's an
2383 // ivar, that's an error.
2384 bool IsClassMethod = CurMethod->isClassMethod();
2385
2386 bool LookForIvars;
2387 if (Lookup.empty())
2388 LookForIvars = true;
2389 else if (IsClassMethod)
2390 LookForIvars = false;
2391 else
2392 LookForIvars = (Lookup.isSingleResult() &&
2393 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod());
2394 ObjCInterfaceDecl *IFace = nullptr;
2395 if (LookForIvars) {
2396 IFace = CurMethod->getClassInterface();
2397 ObjCInterfaceDecl *ClassDeclared;
2398 ObjCIvarDecl *IV = nullptr;
2399 if (IFace && (IV = IFace->lookupInstanceVariable(II, ClassDeclared))) {
2400 // Diagnose using an ivar in a class method.
2401 if (IsClassMethod)
2402 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method)
2403 << IV->getDeclName());
2404
2405 // If we're referencing an invalid decl, just return this as a silent
2406 // error node. The error diagnostic was already emitted on the decl.
2407 if (IV->isInvalidDecl())
2408 return ExprError();
2409
2410 // Check if referencing a field with __attribute__((deprecated)).
2411 if (DiagnoseUseOfDecl(IV, Loc))
2412 return ExprError();
2413
2414 // Diagnose the use of an ivar outside of the declaring class.
2415 if (IV->getAccessControl() == ObjCIvarDecl::Private &&
2416 !declaresSameEntity(ClassDeclared, IFace) &&
2417 !getLangOpts().DebuggerSupport)
2418 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName();
2419
2420 // FIXME: This should use a new expr for a direct reference, don't
2421 // turn this into Self->ivar, just return a BareIVarExpr or something.
2422 IdentifierInfo &II = Context.Idents.get("self");
2423 UnqualifiedId SelfName;
2424 SelfName.setIdentifier(&II, SourceLocation());
2425 SelfName.setKind(UnqualifiedId::IK_ImplicitSelfParam);
2426 CXXScopeSpec SelfScopeSpec;
2427 SourceLocation TemplateKWLoc;
2428 ExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, TemplateKWLoc,
2429 SelfName, false, false);
2430 if (SelfExpr.isInvalid())
2431 return ExprError();
2432
2433 SelfExpr = DefaultLvalueConversion(SelfExpr.get());
2434 if (SelfExpr.isInvalid())
2435 return ExprError();
2436
2437 MarkAnyDeclReferenced(Loc, IV, true);
2438
2439 ObjCMethodFamily MF = CurMethod->getMethodFamily();
2440 if (MF != OMF_init && MF != OMF_dealloc && MF != OMF_finalize &&
2441 !IvarBacksCurrentMethodAccessor(IFace, CurMethod, IV))
2442 Diag(Loc, diag::warn_direct_ivar_access) << IV->getDeclName();
2443
2444 ObjCIvarRefExpr *Result = new (Context)
2445 ObjCIvarRefExpr(IV, IV->getUsageType(SelfExpr.get()->getType()), Loc,
2446 IV->getLocation(), SelfExpr.get(), true, true);
2447
2448 if (getLangOpts().ObjCAutoRefCount) {
2449 if (IV->getType().getObjCLifetime() == Qualifiers::OCL_Weak) {
2450 if (!Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, Loc))
2451 recordUseOfEvaluatedWeak(Result);
2452 }
2453 if (CurContext->isClosure())
2454 Diag(Loc, diag::warn_implicitly_retains_self)
2455 << FixItHint::CreateInsertion(Loc, "self->");
2456 }
2457
2458 return Result;
2459 }
2460 } else if (CurMethod->isInstanceMethod()) {
2461 // We should warn if a local variable hides an ivar.
2462 if (ObjCInterfaceDecl *IFace = CurMethod->getClassInterface()) {
2463 ObjCInterfaceDecl *ClassDeclared;
2464 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) {
2465 if (IV->getAccessControl() != ObjCIvarDecl::Private ||
2466 declaresSameEntity(IFace, ClassDeclared))
2467 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName();
2468 }
2469 }
2470 } else if (Lookup.isSingleResult() &&
2471 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()) {
2472 // If accessing a stand-alone ivar in a class method, this is an error.
2473 if (const ObjCIvarDecl *IV = dyn_cast<ObjCIvarDecl>(Lookup.getFoundDecl()))
2474 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method)
2475 << IV->getDeclName());
2476 }
2477
2478 if (Lookup.empty() && II && AllowBuiltinCreation) {
2479 // FIXME. Consolidate this with similar code in LookupName.
2480 if (unsigned BuiltinID = II->getBuiltinID()) {
2481 if (!(getLangOpts().CPlusPlus &&
2482 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) {
2483 NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID,
2484 S, Lookup.isForRedeclaration(),
2485 Lookup.getNameLoc());
2486 if (D) Lookup.addDecl(D);
2487 }
2488 }
2489 }
2490 // Sentinel value saying that we didn't do anything special.
2491 return ExprResult((Expr *)nullptr);
2492 }
2493
2494 /// \brief Cast a base object to a member's actual type.
2495 ///
2496 /// Logically this happens in three phases:
2497 ///
2498 /// * First we cast from the base type to the naming class.
2499 /// The naming class is the class into which we were looking
2500 /// when we found the member; it's the qualifier type if a
2501 /// qualifier was provided, and otherwise it's the base type.
2502 ///
2503 /// * Next we cast from the naming class to the declaring class.
2504 /// If the member we found was brought into a class's scope by
2505 /// a using declaration, this is that class; otherwise it's
2506 /// the class declaring the member.
2507 ///
2508 /// * Finally we cast from the declaring class to the "true"
2509 /// declaring class of the member. This conversion does not
2510 /// obey access control.
2511 ExprResult
PerformObjectMemberConversion(Expr * From,NestedNameSpecifier * Qualifier,NamedDecl * FoundDecl,NamedDecl * Member)2512 Sema::PerformObjectMemberConversion(Expr *From,
2513 NestedNameSpecifier *Qualifier,
2514 NamedDecl *FoundDecl,
2515 NamedDecl *Member) {
2516 CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Member->getDeclContext());
2517 if (!RD)
2518 return From;
2519
2520 QualType DestRecordType;
2521 QualType DestType;
2522 QualType FromRecordType;
2523 QualType FromType = From->getType();
2524 bool PointerConversions = false;
2525 if (isa<FieldDecl>(Member)) {
2526 DestRecordType = Context.getCanonicalType(Context.getTypeDeclType(RD));
2527
2528 if (FromType->getAs<PointerType>()) {
2529 DestType = Context.getPointerType(DestRecordType);
2530 FromRecordType = FromType->getPointeeType();
2531 PointerConversions = true;
2532 } else {
2533 DestType = DestRecordType;
2534 FromRecordType = FromType;
2535 }
2536 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) {
2537 if (Method->isStatic())
2538 return From;
2539
2540 DestType = Method->getThisType(Context);
2541 DestRecordType = DestType->getPointeeType();
2542
2543 if (FromType->getAs<PointerType>()) {
2544 FromRecordType = FromType->getPointeeType();
2545 PointerConversions = true;
2546 } else {
2547 FromRecordType = FromType;
2548 DestType = DestRecordType;
2549 }
2550 } else {
2551 // No conversion necessary.
2552 return From;
2553 }
2554
2555 if (DestType->isDependentType() || FromType->isDependentType())
2556 return From;
2557
2558 // If the unqualified types are the same, no conversion is necessary.
2559 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType))
2560 return From;
2561
2562 SourceRange FromRange = From->getSourceRange();
2563 SourceLocation FromLoc = FromRange.getBegin();
2564
2565 ExprValueKind VK = From->getValueKind();
2566
2567 // C++ [class.member.lookup]p8:
2568 // [...] Ambiguities can often be resolved by qualifying a name with its
2569 // class name.
2570 //
2571 // If the member was a qualified name and the qualified referred to a
2572 // specific base subobject type, we'll cast to that intermediate type
2573 // first and then to the object in which the member is declared. That allows
2574 // one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as:
2575 //
2576 // class Base { public: int x; };
2577 // class Derived1 : public Base { };
2578 // class Derived2 : public Base { };
2579 // class VeryDerived : public Derived1, public Derived2 { void f(); };
2580 //
2581 // void VeryDerived::f() {
2582 // x = 17; // error: ambiguous base subobjects
2583 // Derived1::x = 17; // okay, pick the Base subobject of Derived1
2584 // }
2585 if (Qualifier && Qualifier->getAsType()) {
2586 QualType QType = QualType(Qualifier->getAsType(), 0);
2587 assert(QType->isRecordType() && "lookup done with non-record type");
2588
2589 QualType QRecordType = QualType(QType->getAs<RecordType>(), 0);
2590
2591 // In C++98, the qualifier type doesn't actually have to be a base
2592 // type of the object type, in which case we just ignore it.
2593 // Otherwise build the appropriate casts.
2594 if (IsDerivedFrom(FromLoc, FromRecordType, QRecordType)) {
2595 CXXCastPath BasePath;
2596 if (CheckDerivedToBaseConversion(FromRecordType, QRecordType,
2597 FromLoc, FromRange, &BasePath))
2598 return ExprError();
2599
2600 if (PointerConversions)
2601 QType = Context.getPointerType(QType);
2602 From = ImpCastExprToType(From, QType, CK_UncheckedDerivedToBase,
2603 VK, &BasePath).get();
2604
2605 FromType = QType;
2606 FromRecordType = QRecordType;
2607
2608 // If the qualifier type was the same as the destination type,
2609 // we're done.
2610 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType))
2611 return From;
2612 }
2613 }
2614
2615 bool IgnoreAccess = false;
2616
2617 // If we actually found the member through a using declaration, cast
2618 // down to the using declaration's type.
2619 //
2620 // Pointer equality is fine here because only one declaration of a
2621 // class ever has member declarations.
2622 if (FoundDecl->getDeclContext() != Member->getDeclContext()) {
2623 assert(isa<UsingShadowDecl>(FoundDecl));
2624 QualType URecordType = Context.getTypeDeclType(
2625 cast<CXXRecordDecl>(FoundDecl->getDeclContext()));
2626
2627 // We only need to do this if the naming-class to declaring-class
2628 // conversion is non-trivial.
2629 if (!Context.hasSameUnqualifiedType(FromRecordType, URecordType)) {
2630 assert(IsDerivedFrom(FromLoc, FromRecordType, URecordType));
2631 CXXCastPath BasePath;
2632 if (CheckDerivedToBaseConversion(FromRecordType, URecordType,
2633 FromLoc, FromRange, &BasePath))
2634 return ExprError();
2635
2636 QualType UType = URecordType;
2637 if (PointerConversions)
2638 UType = Context.getPointerType(UType);
2639 From = ImpCastExprToType(From, UType, CK_UncheckedDerivedToBase,
2640 VK, &BasePath).get();
2641 FromType = UType;
2642 FromRecordType = URecordType;
2643 }
2644
2645 // We don't do access control for the conversion from the
2646 // declaring class to the true declaring class.
2647 IgnoreAccess = true;
2648 }
2649
2650 CXXCastPath BasePath;
2651 if (CheckDerivedToBaseConversion(FromRecordType, DestRecordType,
2652 FromLoc, FromRange, &BasePath,
2653 IgnoreAccess))
2654 return ExprError();
2655
2656 return ImpCastExprToType(From, DestType, CK_UncheckedDerivedToBase,
2657 VK, &BasePath);
2658 }
2659
UseArgumentDependentLookup(const CXXScopeSpec & SS,const LookupResult & R,bool HasTrailingLParen)2660 bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS,
2661 const LookupResult &R,
2662 bool HasTrailingLParen) {
2663 // Only when used directly as the postfix-expression of a call.
2664 if (!HasTrailingLParen)
2665 return false;
2666
2667 // Never if a scope specifier was provided.
2668 if (SS.isSet())
2669 return false;
2670
2671 // Only in C++ or ObjC++.
2672 if (!getLangOpts().CPlusPlus)
2673 return false;
2674
2675 // Turn off ADL when we find certain kinds of declarations during
2676 // normal lookup:
2677 for (NamedDecl *D : R) {
2678 // C++0x [basic.lookup.argdep]p3:
2679 // -- a declaration of a class member
2680 // Since using decls preserve this property, we check this on the
2681 // original decl.
2682 if (D->isCXXClassMember())
2683 return false;
2684
2685 // C++0x [basic.lookup.argdep]p3:
2686 // -- a block-scope function declaration that is not a
2687 // using-declaration
2688 // NOTE: we also trigger this for function templates (in fact, we
2689 // don't check the decl type at all, since all other decl types
2690 // turn off ADL anyway).
2691 if (isa<UsingShadowDecl>(D))
2692 D = cast<UsingShadowDecl>(D)->getTargetDecl();
2693 else if (D->getLexicalDeclContext()->isFunctionOrMethod())
2694 return false;
2695
2696 // C++0x [basic.lookup.argdep]p3:
2697 // -- a declaration that is neither a function or a function
2698 // template
2699 // And also for builtin functions.
2700 if (isa<FunctionDecl>(D)) {
2701 FunctionDecl *FDecl = cast<FunctionDecl>(D);
2702
2703 // But also builtin functions.
2704 if (FDecl->getBuiltinID() && FDecl->isImplicit())
2705 return false;
2706 } else if (!isa<FunctionTemplateDecl>(D))
2707 return false;
2708 }
2709
2710 return true;
2711 }
2712
2713
2714 /// Diagnoses obvious problems with the use of the given declaration
2715 /// as an expression. This is only actually called for lookups that
2716 /// were not overloaded, and it doesn't promise that the declaration
2717 /// will in fact be used.
CheckDeclInExpr(Sema & S,SourceLocation Loc,NamedDecl * D)2718 static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) {
2719 if (isa<TypedefNameDecl>(D)) {
2720 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName();
2721 return true;
2722 }
2723
2724 if (isa<ObjCInterfaceDecl>(D)) {
2725 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName();
2726 return true;
2727 }
2728
2729 if (isa<NamespaceDecl>(D)) {
2730 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName();
2731 return true;
2732 }
2733
2734 return false;
2735 }
2736
BuildDeclarationNameExpr(const CXXScopeSpec & SS,LookupResult & R,bool NeedsADL,bool AcceptInvalidDecl)2737 ExprResult Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS,
2738 LookupResult &R, bool NeedsADL,
2739 bool AcceptInvalidDecl) {
2740 // If this is a single, fully-resolved result and we don't need ADL,
2741 // just build an ordinary singleton decl ref.
2742 if (!NeedsADL && R.isSingleResult() && !R.getAsSingle<FunctionTemplateDecl>())
2743 return BuildDeclarationNameExpr(SS, R.getLookupNameInfo(), R.getFoundDecl(),
2744 R.getRepresentativeDecl(), nullptr,
2745 AcceptInvalidDecl);
2746
2747 // We only need to check the declaration if there's exactly one
2748 // result, because in the overloaded case the results can only be
2749 // functions and function templates.
2750 if (R.isSingleResult() &&
2751 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl()))
2752 return ExprError();
2753
2754 // Otherwise, just build an unresolved lookup expression. Suppress
2755 // any lookup-related diagnostics; we'll hash these out later, when
2756 // we've picked a target.
2757 R.suppressDiagnostics();
2758
2759 UnresolvedLookupExpr *ULE
2760 = UnresolvedLookupExpr::Create(Context, R.getNamingClass(),
2761 SS.getWithLocInContext(Context),
2762 R.getLookupNameInfo(),
2763 NeedsADL, R.isOverloadedResult(),
2764 R.begin(), R.end());
2765
2766 return ULE;
2767 }
2768
2769 /// \brief Complete semantic analysis for a reference to the given declaration.
BuildDeclarationNameExpr(const CXXScopeSpec & SS,const DeclarationNameInfo & NameInfo,NamedDecl * D,NamedDecl * FoundD,const TemplateArgumentListInfo * TemplateArgs,bool AcceptInvalidDecl)2770 ExprResult Sema::BuildDeclarationNameExpr(
2771 const CXXScopeSpec &SS, const DeclarationNameInfo &NameInfo, NamedDecl *D,
2772 NamedDecl *FoundD, const TemplateArgumentListInfo *TemplateArgs,
2773 bool AcceptInvalidDecl) {
2774 assert(D && "Cannot refer to a NULL declaration");
2775 assert(!isa<FunctionTemplateDecl>(D) &&
2776 "Cannot refer unambiguously to a function template");
2777
2778 SourceLocation Loc = NameInfo.getLoc();
2779 if (CheckDeclInExpr(*this, Loc, D))
2780 return ExprError();
2781
2782 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) {
2783 // Specifically diagnose references to class templates that are missing
2784 // a template argument list.
2785 Diag(Loc, diag::err_template_decl_ref) << (isa<VarTemplateDecl>(D) ? 1 : 0)
2786 << Template << SS.getRange();
2787 Diag(Template->getLocation(), diag::note_template_decl_here);
2788 return ExprError();
2789 }
2790
2791 // Make sure that we're referring to a value.
2792 ValueDecl *VD = dyn_cast<ValueDecl>(D);
2793 if (!VD) {
2794 Diag(Loc, diag::err_ref_non_value)
2795 << D << SS.getRange();
2796 Diag(D->getLocation(), diag::note_declared_at);
2797 return ExprError();
2798 }
2799
2800 // Check whether this declaration can be used. Note that we suppress
2801 // this check when we're going to perform argument-dependent lookup
2802 // on this function name, because this might not be the function
2803 // that overload resolution actually selects.
2804 if (DiagnoseUseOfDecl(VD, Loc))
2805 return ExprError();
2806
2807 // Only create DeclRefExpr's for valid Decl's.
2808 if (VD->isInvalidDecl() && !AcceptInvalidDecl)
2809 return ExprError();
2810
2811 // Handle members of anonymous structs and unions. If we got here,
2812 // and the reference is to a class member indirect field, then this
2813 // must be the subject of a pointer-to-member expression.
2814 if (IndirectFieldDecl *indirectField = dyn_cast<IndirectFieldDecl>(VD))
2815 if (!indirectField->isCXXClassMember())
2816 return BuildAnonymousStructUnionMemberReference(SS, NameInfo.getLoc(),
2817 indirectField);
2818
2819 {
2820 QualType type = VD->getType();
2821 ExprValueKind valueKind = VK_RValue;
2822
2823 switch (D->getKind()) {
2824 // Ignore all the non-ValueDecl kinds.
2825 #define ABSTRACT_DECL(kind)
2826 #define VALUE(type, base)
2827 #define DECL(type, base) \
2828 case Decl::type:
2829 #include "clang/AST/DeclNodes.inc"
2830 llvm_unreachable("invalid value decl kind");
2831
2832 // These shouldn't make it here.
2833 case Decl::ObjCAtDefsField:
2834 case Decl::ObjCIvar:
2835 llvm_unreachable("forming non-member reference to ivar?");
2836
2837 // Enum constants are always r-values and never references.
2838 // Unresolved using declarations are dependent.
2839 case Decl::EnumConstant:
2840 case Decl::UnresolvedUsingValue:
2841 valueKind = VK_RValue;
2842 break;
2843
2844 // Fields and indirect fields that got here must be for
2845 // pointer-to-member expressions; we just call them l-values for
2846 // internal consistency, because this subexpression doesn't really
2847 // exist in the high-level semantics.
2848 case Decl::Field:
2849 case Decl::IndirectField:
2850 assert(getLangOpts().CPlusPlus &&
2851 "building reference to field in C?");
2852
2853 // These can't have reference type in well-formed programs, but
2854 // for internal consistency we do this anyway.
2855 type = type.getNonReferenceType();
2856 valueKind = VK_LValue;
2857 break;
2858
2859 // Non-type template parameters are either l-values or r-values
2860 // depending on the type.
2861 case Decl::NonTypeTemplateParm: {
2862 if (const ReferenceType *reftype = type->getAs<ReferenceType>()) {
2863 type = reftype->getPointeeType();
2864 valueKind = VK_LValue; // even if the parameter is an r-value reference
2865 break;
2866 }
2867
2868 // For non-references, we need to strip qualifiers just in case
2869 // the template parameter was declared as 'const int' or whatever.
2870 valueKind = VK_RValue;
2871 type = type.getUnqualifiedType();
2872 break;
2873 }
2874
2875 case Decl::Var:
2876 case Decl::VarTemplateSpecialization:
2877 case Decl::VarTemplatePartialSpecialization:
2878 // In C, "extern void blah;" is valid and is an r-value.
2879 if (!getLangOpts().CPlusPlus &&
2880 !type.hasQualifiers() &&
2881 type->isVoidType()) {
2882 valueKind = VK_RValue;
2883 break;
2884 }
2885 // fallthrough
2886
2887 case Decl::ImplicitParam:
2888 case Decl::ParmVar: {
2889 // These are always l-values.
2890 valueKind = VK_LValue;
2891 type = type.getNonReferenceType();
2892
2893 // FIXME: Does the addition of const really only apply in
2894 // potentially-evaluated contexts? Since the variable isn't actually
2895 // captured in an unevaluated context, it seems that the answer is no.
2896 if (!isUnevaluatedContext()) {
2897 QualType CapturedType = getCapturedDeclRefType(cast<VarDecl>(VD), Loc);
2898 if (!CapturedType.isNull())
2899 type = CapturedType;
2900 }
2901
2902 break;
2903 }
2904
2905 case Decl::Function: {
2906 if (unsigned BID = cast<FunctionDecl>(VD)->getBuiltinID()) {
2907 if (!Context.BuiltinInfo.isPredefinedLibFunction(BID)) {
2908 type = Context.BuiltinFnTy;
2909 valueKind = VK_RValue;
2910 break;
2911 }
2912 }
2913
2914 const FunctionType *fty = type->castAs<FunctionType>();
2915
2916 // If we're referring to a function with an __unknown_anytype
2917 // result type, make the entire expression __unknown_anytype.
2918 if (fty->getReturnType() == Context.UnknownAnyTy) {
2919 type = Context.UnknownAnyTy;
2920 valueKind = VK_RValue;
2921 break;
2922 }
2923
2924 // Functions are l-values in C++.
2925 if (getLangOpts().CPlusPlus) {
2926 valueKind = VK_LValue;
2927 break;
2928 }
2929
2930 // C99 DR 316 says that, if a function type comes from a
2931 // function definition (without a prototype), that type is only
2932 // used for checking compatibility. Therefore, when referencing
2933 // the function, we pretend that we don't have the full function
2934 // type.
2935 if (!cast<FunctionDecl>(VD)->hasPrototype() &&
2936 isa<FunctionProtoType>(fty))
2937 type = Context.getFunctionNoProtoType(fty->getReturnType(),
2938 fty->getExtInfo());
2939
2940 // Functions are r-values in C.
2941 valueKind = VK_RValue;
2942 break;
2943 }
2944
2945 case Decl::MSProperty:
2946 valueKind = VK_LValue;
2947 break;
2948
2949 case Decl::CXXMethod:
2950 // If we're referring to a method with an __unknown_anytype
2951 // result type, make the entire expression __unknown_anytype.
2952 // This should only be possible with a type written directly.
2953 if (const FunctionProtoType *proto
2954 = dyn_cast<FunctionProtoType>(VD->getType()))
2955 if (proto->getReturnType() == Context.UnknownAnyTy) {
2956 type = Context.UnknownAnyTy;
2957 valueKind = VK_RValue;
2958 break;
2959 }
2960
2961 // C++ methods are l-values if static, r-values if non-static.
2962 if (cast<CXXMethodDecl>(VD)->isStatic()) {
2963 valueKind = VK_LValue;
2964 break;
2965 }
2966 // fallthrough
2967
2968 case Decl::CXXConversion:
2969 case Decl::CXXDestructor:
2970 case Decl::CXXConstructor:
2971 valueKind = VK_RValue;
2972 break;
2973 }
2974
2975 return BuildDeclRefExpr(VD, type, valueKind, NameInfo, &SS, FoundD,
2976 TemplateArgs);
2977 }
2978 }
2979
ConvertUTF8ToWideString(unsigned CharByteWidth,StringRef Source,SmallString<32> & Target)2980 static void ConvertUTF8ToWideString(unsigned CharByteWidth, StringRef Source,
2981 SmallString<32> &Target) {
2982 Target.resize(CharByteWidth * (Source.size() + 1));
2983 char *ResultPtr = &Target[0];
2984 const UTF8 *ErrorPtr;
2985 bool success = ConvertUTF8toWide(CharByteWidth, Source, ResultPtr, ErrorPtr);
2986 (void)success;
2987 assert(success);
2988 Target.resize(ResultPtr - &Target[0]);
2989 }
2990
BuildPredefinedExpr(SourceLocation Loc,PredefinedExpr::IdentType IT)2991 ExprResult Sema::BuildPredefinedExpr(SourceLocation Loc,
2992 PredefinedExpr::IdentType IT) {
2993 // Pick the current block, lambda, captured statement or function.
2994 Decl *currentDecl = nullptr;
2995 if (const BlockScopeInfo *BSI = getCurBlock())
2996 currentDecl = BSI->TheDecl;
2997 else if (const LambdaScopeInfo *LSI = getCurLambda())
2998 currentDecl = LSI->CallOperator;
2999 else if (const CapturedRegionScopeInfo *CSI = getCurCapturedRegion())
3000 currentDecl = CSI->TheCapturedDecl;
3001 else
3002 currentDecl = getCurFunctionOrMethodDecl();
3003
3004 if (!currentDecl) {
3005 Diag(Loc, diag::ext_predef_outside_function);
3006 currentDecl = Context.getTranslationUnitDecl();
3007 }
3008
3009 QualType ResTy;
3010 StringLiteral *SL = nullptr;
3011 if (cast<DeclContext>(currentDecl)->isDependentContext())
3012 ResTy = Context.DependentTy;
3013 else {
3014 // Pre-defined identifiers are of type char[x], where x is the length of
3015 // the string.
3016 auto Str = PredefinedExpr::ComputeName(IT, currentDecl);
3017 unsigned Length = Str.length();
3018
3019 llvm::APInt LengthI(32, Length + 1);
3020 if (IT == PredefinedExpr::LFunction) {
3021 ResTy = Context.WideCharTy.withConst();
3022 SmallString<32> RawChars;
3023 ConvertUTF8ToWideString(Context.getTypeSizeInChars(ResTy).getQuantity(),
3024 Str, RawChars);
3025 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal,
3026 /*IndexTypeQuals*/ 0);
3027 SL = StringLiteral::Create(Context, RawChars, StringLiteral::Wide,
3028 /*Pascal*/ false, ResTy, Loc);
3029 } else {
3030 ResTy = Context.CharTy.withConst();
3031 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal,
3032 /*IndexTypeQuals*/ 0);
3033 SL = StringLiteral::Create(Context, Str, StringLiteral::Ascii,
3034 /*Pascal*/ false, ResTy, Loc);
3035 }
3036 }
3037
3038 return new (Context) PredefinedExpr(Loc, ResTy, IT, SL);
3039 }
3040
ActOnPredefinedExpr(SourceLocation Loc,tok::TokenKind Kind)3041 ExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, tok::TokenKind Kind) {
3042 PredefinedExpr::IdentType IT;
3043
3044 switch (Kind) {
3045 default: llvm_unreachable("Unknown simple primary expr!");
3046 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2]
3047 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break;
3048 case tok::kw___FUNCDNAME__: IT = PredefinedExpr::FuncDName; break; // [MS]
3049 case tok::kw___FUNCSIG__: IT = PredefinedExpr::FuncSig; break; // [MS]
3050 case tok::kw_L__FUNCTION__: IT = PredefinedExpr::LFunction; break;
3051 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break;
3052 }
3053
3054 return BuildPredefinedExpr(Loc, IT);
3055 }
3056
ActOnCharacterConstant(const Token & Tok,Scope * UDLScope)3057 ExprResult Sema::ActOnCharacterConstant(const Token &Tok, Scope *UDLScope) {
3058 SmallString<16> CharBuffer;
3059 bool Invalid = false;
3060 StringRef ThisTok = PP.getSpelling(Tok, CharBuffer, &Invalid);
3061 if (Invalid)
3062 return ExprError();
3063
3064 CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(),
3065 PP, Tok.getKind());
3066 if (Literal.hadError())
3067 return ExprError();
3068
3069 QualType Ty;
3070 if (Literal.isWide())
3071 Ty = Context.WideCharTy; // L'x' -> wchar_t in C and C++.
3072 else if (Literal.isUTF16())
3073 Ty = Context.Char16Ty; // u'x' -> char16_t in C11 and C++11.
3074 else if (Literal.isUTF32())
3075 Ty = Context.Char32Ty; // U'x' -> char32_t in C11 and C++11.
3076 else if (!getLangOpts().CPlusPlus || Literal.isMultiChar())
3077 Ty = Context.IntTy; // 'x' -> int in C, 'wxyz' -> int in C++.
3078 else
3079 Ty = Context.CharTy; // 'x' -> char in C++
3080
3081 CharacterLiteral::CharacterKind Kind = CharacterLiteral::Ascii;
3082 if (Literal.isWide())
3083 Kind = CharacterLiteral::Wide;
3084 else if (Literal.isUTF16())
3085 Kind = CharacterLiteral::UTF16;
3086 else if (Literal.isUTF32())
3087 Kind = CharacterLiteral::UTF32;
3088
3089 Expr *Lit = new (Context) CharacterLiteral(Literal.getValue(), Kind, Ty,
3090 Tok.getLocation());
3091
3092 if (Literal.getUDSuffix().empty())
3093 return Lit;
3094
3095 // We're building a user-defined literal.
3096 IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix());
3097 SourceLocation UDSuffixLoc =
3098 getUDSuffixLoc(*this, Tok.getLocation(), Literal.getUDSuffixOffset());
3099
3100 // Make sure we're allowed user-defined literals here.
3101 if (!UDLScope)
3102 return ExprError(Diag(UDSuffixLoc, diag::err_invalid_character_udl));
3103
3104 // C++11 [lex.ext]p6: The literal L is treated as a call of the form
3105 // operator "" X (ch)
3106 return BuildCookedLiteralOperatorCall(*this, UDLScope, UDSuffix, UDSuffixLoc,
3107 Lit, Tok.getLocation());
3108 }
3109
ActOnIntegerConstant(SourceLocation Loc,uint64_t Val)3110 ExprResult Sema::ActOnIntegerConstant(SourceLocation Loc, uint64_t Val) {
3111 unsigned IntSize = Context.getTargetInfo().getIntWidth();
3112 return IntegerLiteral::Create(Context, llvm::APInt(IntSize, Val),
3113 Context.IntTy, Loc);
3114 }
3115
BuildFloatingLiteral(Sema & S,NumericLiteralParser & Literal,QualType Ty,SourceLocation Loc)3116 static Expr *BuildFloatingLiteral(Sema &S, NumericLiteralParser &Literal,
3117 QualType Ty, SourceLocation Loc) {
3118 const llvm::fltSemantics &Format = S.Context.getFloatTypeSemantics(Ty);
3119
3120 using llvm::APFloat;
3121 APFloat Val(Format);
3122
3123 APFloat::opStatus result = Literal.GetFloatValue(Val);
3124
3125 // Overflow is always an error, but underflow is only an error if
3126 // we underflowed to zero (APFloat reports denormals as underflow).
3127 if ((result & APFloat::opOverflow) ||
3128 ((result & APFloat::opUnderflow) && Val.isZero())) {
3129 unsigned diagnostic;
3130 SmallString<20> buffer;
3131 if (result & APFloat::opOverflow) {
3132 diagnostic = diag::warn_float_overflow;
3133 APFloat::getLargest(Format).toString(buffer);
3134 } else {
3135 diagnostic = diag::warn_float_underflow;
3136 APFloat::getSmallest(Format).toString(buffer);
3137 }
3138
3139 S.Diag(Loc, diagnostic)
3140 << Ty
3141 << StringRef(buffer.data(), buffer.size());
3142 }
3143
3144 bool isExact = (result == APFloat::opOK);
3145 return FloatingLiteral::Create(S.Context, Val, isExact, Ty, Loc);
3146 }
3147
CheckLoopHintExpr(Expr * E,SourceLocation Loc)3148 bool Sema::CheckLoopHintExpr(Expr *E, SourceLocation Loc) {
3149 assert(E && "Invalid expression");
3150
3151 if (E->isValueDependent())
3152 return false;
3153
3154 QualType QT = E->getType();
3155 if (!QT->isIntegerType() || QT->isBooleanType() || QT->isCharType()) {
3156 Diag(E->getExprLoc(), diag::err_pragma_loop_invalid_argument_type) << QT;
3157 return true;
3158 }
3159
3160 llvm::APSInt ValueAPS;
3161 ExprResult R = VerifyIntegerConstantExpression(E, &ValueAPS);
3162
3163 if (R.isInvalid())
3164 return true;
3165
3166 bool ValueIsPositive = ValueAPS.isStrictlyPositive();
3167 if (!ValueIsPositive || ValueAPS.getActiveBits() > 31) {
3168 Diag(E->getExprLoc(), diag::err_pragma_loop_invalid_argument_value)
3169 << ValueAPS.toString(10) << ValueIsPositive;
3170 return true;
3171 }
3172
3173 return false;
3174 }
3175
ActOnNumericConstant(const Token & Tok,Scope * UDLScope)3176 ExprResult Sema::ActOnNumericConstant(const Token &Tok, Scope *UDLScope) {
3177 // Fast path for a single digit (which is quite common). A single digit
3178 // cannot have a trigraph, escaped newline, radix prefix, or suffix.
3179 if (Tok.getLength() == 1) {
3180 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok);
3181 return ActOnIntegerConstant(Tok.getLocation(), Val-'0');
3182 }
3183
3184 SmallString<128> SpellingBuffer;
3185 // NumericLiteralParser wants to overread by one character. Add padding to
3186 // the buffer in case the token is copied to the buffer. If getSpelling()
3187 // returns a StringRef to the memory buffer, it should have a null char at
3188 // the EOF, so it is also safe.
3189 SpellingBuffer.resize(Tok.getLength() + 1);
3190
3191 // Get the spelling of the token, which eliminates trigraphs, etc.
3192 bool Invalid = false;
3193 StringRef TokSpelling = PP.getSpelling(Tok, SpellingBuffer, &Invalid);
3194 if (Invalid)
3195 return ExprError();
3196
3197 NumericLiteralParser Literal(TokSpelling, Tok.getLocation(), PP);
3198 if (Literal.hadError)
3199 return ExprError();
3200
3201 if (Literal.hasUDSuffix()) {
3202 // We're building a user-defined literal.
3203 IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix());
3204 SourceLocation UDSuffixLoc =
3205 getUDSuffixLoc(*this, Tok.getLocation(), Literal.getUDSuffixOffset());
3206
3207 // Make sure we're allowed user-defined literals here.
3208 if (!UDLScope)
3209 return ExprError(Diag(UDSuffixLoc, diag::err_invalid_numeric_udl));
3210
3211 QualType CookedTy;
3212 if (Literal.isFloatingLiteral()) {
3213 // C++11 [lex.ext]p4: If S contains a literal operator with parameter type
3214 // long double, the literal is treated as a call of the form
3215 // operator "" X (f L)
3216 CookedTy = Context.LongDoubleTy;
3217 } else {
3218 // C++11 [lex.ext]p3: If S contains a literal operator with parameter type
3219 // unsigned long long, the literal is treated as a call of the form
3220 // operator "" X (n ULL)
3221 CookedTy = Context.UnsignedLongLongTy;
3222 }
3223
3224 DeclarationName OpName =
3225 Context.DeclarationNames.getCXXLiteralOperatorName(UDSuffix);
3226 DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc);
3227 OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc);
3228
3229 SourceLocation TokLoc = Tok.getLocation();
3230
3231 // Perform literal operator lookup to determine if we're building a raw
3232 // literal or a cooked one.
3233 LookupResult R(*this, OpName, UDSuffixLoc, LookupOrdinaryName);
3234 switch (LookupLiteralOperator(UDLScope, R, CookedTy,
3235 /*AllowRaw*/true, /*AllowTemplate*/true,
3236 /*AllowStringTemplate*/false)) {
3237 case LOLR_Error:
3238 return ExprError();
3239
3240 case LOLR_Cooked: {
3241 Expr *Lit;
3242 if (Literal.isFloatingLiteral()) {
3243 Lit = BuildFloatingLiteral(*this, Literal, CookedTy, Tok.getLocation());
3244 } else {
3245 llvm::APInt ResultVal(Context.getTargetInfo().getLongLongWidth(), 0);
3246 if (Literal.GetIntegerValue(ResultVal))
3247 Diag(Tok.getLocation(), diag::err_integer_literal_too_large)
3248 << /* Unsigned */ 1;
3249 Lit = IntegerLiteral::Create(Context, ResultVal, CookedTy,
3250 Tok.getLocation());
3251 }
3252 return BuildLiteralOperatorCall(R, OpNameInfo, Lit, TokLoc);
3253 }
3254
3255 case LOLR_Raw: {
3256 // C++11 [lit.ext]p3, p4: If S contains a raw literal operator, the
3257 // literal is treated as a call of the form
3258 // operator "" X ("n")
3259 unsigned Length = Literal.getUDSuffixOffset();
3260 QualType StrTy = Context.getConstantArrayType(
3261 Context.CharTy.withConst(), llvm::APInt(32, Length + 1),
3262 ArrayType::Normal, 0);
3263 Expr *Lit = StringLiteral::Create(
3264 Context, StringRef(TokSpelling.data(), Length), StringLiteral::Ascii,
3265 /*Pascal*/false, StrTy, &TokLoc, 1);
3266 return BuildLiteralOperatorCall(R, OpNameInfo, Lit, TokLoc);
3267 }
3268
3269 case LOLR_Template: {
3270 // C++11 [lit.ext]p3, p4: Otherwise (S contains a literal operator
3271 // template), L is treated as a call fo the form
3272 // operator "" X <'c1', 'c2', ... 'ck'>()
3273 // where n is the source character sequence c1 c2 ... ck.
3274 TemplateArgumentListInfo ExplicitArgs;
3275 unsigned CharBits = Context.getIntWidth(Context.CharTy);
3276 bool CharIsUnsigned = Context.CharTy->isUnsignedIntegerType();
3277 llvm::APSInt Value(CharBits, CharIsUnsigned);
3278 for (unsigned I = 0, N = Literal.getUDSuffixOffset(); I != N; ++I) {
3279 Value = TokSpelling[I];
3280 TemplateArgument Arg(Context, Value, Context.CharTy);
3281 TemplateArgumentLocInfo ArgInfo;
3282 ExplicitArgs.addArgument(TemplateArgumentLoc(Arg, ArgInfo));
3283 }
3284 return BuildLiteralOperatorCall(R, OpNameInfo, None, TokLoc,
3285 &ExplicitArgs);
3286 }
3287 case LOLR_StringTemplate:
3288 llvm_unreachable("unexpected literal operator lookup result");
3289 }
3290 }
3291
3292 Expr *Res;
3293
3294 if (Literal.isFloatingLiteral()) {
3295 QualType Ty;
3296 if (Literal.isFloat)
3297 Ty = Context.FloatTy;
3298 else if (!Literal.isLong)
3299 Ty = Context.DoubleTy;
3300 else
3301 Ty = Context.LongDoubleTy;
3302
3303 Res = BuildFloatingLiteral(*this, Literal, Ty, Tok.getLocation());
3304
3305 if (Ty == Context.DoubleTy) {
3306 if (getLangOpts().SinglePrecisionConstants) {
3307 Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).get();
3308 } else if (getLangOpts().OpenCL &&
3309 !((getLangOpts().OpenCLVersion >= 120) ||
3310 getOpenCLOptions().cl_khr_fp64)) {
3311 Diag(Tok.getLocation(), diag::warn_double_const_requires_fp64);
3312 Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).get();
3313 }
3314 }
3315 } else if (!Literal.isIntegerLiteral()) {
3316 return ExprError();
3317 } else {
3318 QualType Ty;
3319
3320 // 'long long' is a C99 or C++11 feature.
3321 if (!getLangOpts().C99 && Literal.isLongLong) {
3322 if (getLangOpts().CPlusPlus)
3323 Diag(Tok.getLocation(),
3324 getLangOpts().CPlusPlus11 ?
3325 diag::warn_cxx98_compat_longlong : diag::ext_cxx11_longlong);
3326 else
3327 Diag(Tok.getLocation(), diag::ext_c99_longlong);
3328 }
3329
3330 // Get the value in the widest-possible width.
3331 unsigned MaxWidth = Context.getTargetInfo().getIntMaxTWidth();
3332 llvm::APInt ResultVal(MaxWidth, 0);
3333
3334 if (Literal.GetIntegerValue(ResultVal)) {
3335 // If this value didn't fit into uintmax_t, error and force to ull.
3336 Diag(Tok.getLocation(), diag::err_integer_literal_too_large)
3337 << /* Unsigned */ 1;
3338 Ty = Context.UnsignedLongLongTy;
3339 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() &&
3340 "long long is not intmax_t?");
3341 } else {
3342 // If this value fits into a ULL, try to figure out what else it fits into
3343 // according to the rules of C99 6.4.4.1p5.
3344
3345 // Octal, Hexadecimal, and integers with a U suffix are allowed to
3346 // be an unsigned int.
3347 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10;
3348
3349 // Check from smallest to largest, picking the smallest type we can.
3350 unsigned Width = 0;
3351
3352 // Microsoft specific integer suffixes are explicitly sized.
3353 if (Literal.MicrosoftInteger) {
3354 if (Literal.MicrosoftInteger == 8 && !Literal.isUnsigned) {
3355 Width = 8;
3356 Ty = Context.CharTy;
3357 } else {
3358 Width = Literal.MicrosoftInteger;
3359 Ty = Context.getIntTypeForBitwidth(Width,
3360 /*Signed=*/!Literal.isUnsigned);
3361 }
3362 }
3363
3364 if (Ty.isNull() && !Literal.isLong && !Literal.isLongLong) {
3365 // Are int/unsigned possibilities?
3366 unsigned IntSize = Context.getTargetInfo().getIntWidth();
3367
3368 // Does it fit in a unsigned int?
3369 if (ResultVal.isIntN(IntSize)) {
3370 // Does it fit in a signed int?
3371 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0)
3372 Ty = Context.IntTy;
3373 else if (AllowUnsigned)
3374 Ty = Context.UnsignedIntTy;
3375 Width = IntSize;
3376 }
3377 }
3378
3379 // Are long/unsigned long possibilities?
3380 if (Ty.isNull() && !Literal.isLongLong) {
3381 unsigned LongSize = Context.getTargetInfo().getLongWidth();
3382
3383 // Does it fit in a unsigned long?
3384 if (ResultVal.isIntN(LongSize)) {
3385 // Does it fit in a signed long?
3386 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0)
3387 Ty = Context.LongTy;
3388 else if (AllowUnsigned)
3389 Ty = Context.UnsignedLongTy;
3390 // Check according to the rules of C90 6.1.3.2p5. C++03 [lex.icon]p2
3391 // is compatible.
3392 else if (!getLangOpts().C99 && !getLangOpts().CPlusPlus11) {
3393 const unsigned LongLongSize =
3394 Context.getTargetInfo().getLongLongWidth();
3395 Diag(Tok.getLocation(),
3396 getLangOpts().CPlusPlus
3397 ? Literal.isLong
3398 ? diag::warn_old_implicitly_unsigned_long_cxx
3399 : /*C++98 UB*/ diag::
3400 ext_old_implicitly_unsigned_long_cxx
3401 : diag::warn_old_implicitly_unsigned_long)
3402 << (LongLongSize > LongSize ? /*will have type 'long long'*/ 0
3403 : /*will be ill-formed*/ 1);
3404 Ty = Context.UnsignedLongTy;
3405 }
3406 Width = LongSize;
3407 }
3408 }
3409
3410 // Check long long if needed.
3411 if (Ty.isNull()) {
3412 unsigned LongLongSize = Context.getTargetInfo().getLongLongWidth();
3413
3414 // Does it fit in a unsigned long long?
3415 if (ResultVal.isIntN(LongLongSize)) {
3416 // Does it fit in a signed long long?
3417 // To be compatible with MSVC, hex integer literals ending with the
3418 // LL or i64 suffix are always signed in Microsoft mode.
3419 if (!Literal.isUnsigned && (ResultVal[LongLongSize-1] == 0 ||
3420 (getLangOpts().MicrosoftExt && Literal.isLongLong)))
3421 Ty = Context.LongLongTy;
3422 else if (AllowUnsigned)
3423 Ty = Context.UnsignedLongLongTy;
3424 Width = LongLongSize;
3425 }
3426 }
3427
3428 // If we still couldn't decide a type, we probably have something that
3429 // does not fit in a signed long long, but has no U suffix.
3430 if (Ty.isNull()) {
3431 Diag(Tok.getLocation(), diag::ext_integer_literal_too_large_for_signed);
3432 Ty = Context.UnsignedLongLongTy;
3433 Width = Context.getTargetInfo().getLongLongWidth();
3434 }
3435
3436 if (ResultVal.getBitWidth() != Width)
3437 ResultVal = ResultVal.trunc(Width);
3438 }
3439 Res = IntegerLiteral::Create(Context, ResultVal, Ty, Tok.getLocation());
3440 }
3441
3442 // If this is an imaginary literal, create the ImaginaryLiteral wrapper.
3443 if (Literal.isImaginary)
3444 Res = new (Context) ImaginaryLiteral(Res,
3445 Context.getComplexType(Res->getType()));
3446
3447 return Res;
3448 }
3449
ActOnParenExpr(SourceLocation L,SourceLocation R,Expr * E)3450 ExprResult Sema::ActOnParenExpr(SourceLocation L, SourceLocation R, Expr *E) {
3451 assert(E && "ActOnParenExpr() missing expr");
3452 return new (Context) ParenExpr(L, R, E);
3453 }
3454
CheckVecStepTraitOperandType(Sema & S,QualType T,SourceLocation Loc,SourceRange ArgRange)3455 static bool CheckVecStepTraitOperandType(Sema &S, QualType T,
3456 SourceLocation Loc,
3457 SourceRange ArgRange) {
3458 // [OpenCL 1.1 6.11.12] "The vec_step built-in function takes a built-in
3459 // scalar or vector data type argument..."
3460 // Every built-in scalar type (OpenCL 1.1 6.1.1) is either an arithmetic
3461 // type (C99 6.2.5p18) or void.
3462 if (!(T->isArithmeticType() || T->isVoidType() || T->isVectorType())) {
3463 S.Diag(Loc, diag::err_vecstep_non_scalar_vector_type)
3464 << T << ArgRange;
3465 return true;
3466 }
3467
3468 assert((T->isVoidType() || !T->isIncompleteType()) &&
3469 "Scalar types should always be complete");
3470 return false;
3471 }
3472
CheckExtensionTraitOperandType(Sema & S,QualType T,SourceLocation Loc,SourceRange ArgRange,UnaryExprOrTypeTrait TraitKind)3473 static bool CheckExtensionTraitOperandType(Sema &S, QualType T,
3474 SourceLocation Loc,
3475 SourceRange ArgRange,
3476 UnaryExprOrTypeTrait TraitKind) {
3477 // Invalid types must be hard errors for SFINAE in C++.
3478 if (S.LangOpts.CPlusPlus)
3479 return true;
3480
3481 // C99 6.5.3.4p1:
3482 if (T->isFunctionType() &&
3483 (TraitKind == UETT_SizeOf || TraitKind == UETT_AlignOf)) {
3484 // sizeof(function)/alignof(function) is allowed as an extension.
3485 S.Diag(Loc, diag::ext_sizeof_alignof_function_type)
3486 << TraitKind << ArgRange;
3487 return false;
3488 }
3489
3490 // Allow sizeof(void)/alignof(void) as an extension, unless in OpenCL where
3491 // this is an error (OpenCL v1.1 s6.3.k)
3492 if (T->isVoidType()) {
3493 unsigned DiagID = S.LangOpts.OpenCL ? diag::err_opencl_sizeof_alignof_type
3494 : diag::ext_sizeof_alignof_void_type;
3495 S.Diag(Loc, DiagID) << TraitKind << ArgRange;
3496 return false;
3497 }
3498
3499 return true;
3500 }
3501
CheckObjCTraitOperandConstraints(Sema & S,QualType T,SourceLocation Loc,SourceRange ArgRange,UnaryExprOrTypeTrait TraitKind)3502 static bool CheckObjCTraitOperandConstraints(Sema &S, QualType T,
3503 SourceLocation Loc,
3504 SourceRange ArgRange,
3505 UnaryExprOrTypeTrait TraitKind) {
3506 // Reject sizeof(interface) and sizeof(interface<proto>) if the
3507 // runtime doesn't allow it.
3508 if (!S.LangOpts.ObjCRuntime.allowsSizeofAlignof() && T->isObjCObjectType()) {
3509 S.Diag(Loc, diag::err_sizeof_nonfragile_interface)
3510 << T << (TraitKind == UETT_SizeOf)
3511 << ArgRange;
3512 return true;
3513 }
3514
3515 return false;
3516 }
3517
3518 /// \brief Check whether E is a pointer from a decayed array type (the decayed
3519 /// pointer type is equal to T) and emit a warning if it is.
warnOnSizeofOnArrayDecay(Sema & S,SourceLocation Loc,QualType T,Expr * E)3520 static void warnOnSizeofOnArrayDecay(Sema &S, SourceLocation Loc, QualType T,
3521 Expr *E) {
3522 // Don't warn if the operation changed the type.
3523 if (T != E->getType())
3524 return;
3525
3526 // Now look for array decays.
3527 ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E);
3528 if (!ICE || ICE->getCastKind() != CK_ArrayToPointerDecay)
3529 return;
3530
3531 S.Diag(Loc, diag::warn_sizeof_array_decay) << ICE->getSourceRange()
3532 << ICE->getType()
3533 << ICE->getSubExpr()->getType();
3534 }
3535
3536 /// \brief Check the constraints on expression operands to unary type expression
3537 /// and type traits.
3538 ///
3539 /// Completes any types necessary and validates the constraints on the operand
3540 /// expression. The logic mostly mirrors the type-based overload, but may modify
3541 /// the expression as it completes the type for that expression through template
3542 /// instantiation, etc.
CheckUnaryExprOrTypeTraitOperand(Expr * E,UnaryExprOrTypeTrait ExprKind)3543 bool Sema::CheckUnaryExprOrTypeTraitOperand(Expr *E,
3544 UnaryExprOrTypeTrait ExprKind) {
3545 QualType ExprTy = E->getType();
3546 assert(!ExprTy->isReferenceType());
3547
3548 if (ExprKind == UETT_VecStep)
3549 return CheckVecStepTraitOperandType(*this, ExprTy, E->getExprLoc(),
3550 E->getSourceRange());
3551
3552 // Whitelist some types as extensions
3553 if (!CheckExtensionTraitOperandType(*this, ExprTy, E->getExprLoc(),
3554 E->getSourceRange(), ExprKind))
3555 return false;
3556
3557 // 'alignof' applied to an expression only requires the base element type of
3558 // the expression to be complete. 'sizeof' requires the expression's type to
3559 // be complete (and will attempt to complete it if it's an array of unknown
3560 // bound).
3561 if (ExprKind == UETT_AlignOf) {
3562 if (RequireCompleteType(E->getExprLoc(),
3563 Context.getBaseElementType(E->getType()),
3564 diag::err_sizeof_alignof_incomplete_type, ExprKind,
3565 E->getSourceRange()))
3566 return true;
3567 } else {
3568 if (RequireCompleteExprType(E, diag::err_sizeof_alignof_incomplete_type,
3569 ExprKind, E->getSourceRange()))
3570 return true;
3571 }
3572
3573 // Completing the expression's type may have changed it.
3574 ExprTy = E->getType();
3575 assert(!ExprTy->isReferenceType());
3576
3577 if (ExprTy->isFunctionType()) {
3578 Diag(E->getExprLoc(), diag::err_sizeof_alignof_function_type)
3579 << ExprKind << E->getSourceRange();
3580 return true;
3581 }
3582
3583 // The operand for sizeof and alignof is in an unevaluated expression context,
3584 // so side effects could result in unintended consequences.
3585 if ((ExprKind == UETT_SizeOf || ExprKind == UETT_AlignOf) &&
3586 ActiveTemplateInstantiations.empty() && E->HasSideEffects(Context, false))
3587 Diag(E->getExprLoc(), diag::warn_side_effects_unevaluated_context);
3588
3589 if (CheckObjCTraitOperandConstraints(*this, ExprTy, E->getExprLoc(),
3590 E->getSourceRange(), ExprKind))
3591 return true;
3592
3593 if (ExprKind == UETT_SizeOf) {
3594 if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(E->IgnoreParens())) {
3595 if (ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(DeclRef->getFoundDecl())) {
3596 QualType OType = PVD->getOriginalType();
3597 QualType Type = PVD->getType();
3598 if (Type->isPointerType() && OType->isArrayType()) {
3599 Diag(E->getExprLoc(), diag::warn_sizeof_array_param)
3600 << Type << OType;
3601 Diag(PVD->getLocation(), diag::note_declared_at);
3602 }
3603 }
3604 }
3605
3606 // Warn on "sizeof(array op x)" and "sizeof(x op array)", where the array
3607 // decays into a pointer and returns an unintended result. This is most
3608 // likely a typo for "sizeof(array) op x".
3609 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E->IgnoreParens())) {
3610 warnOnSizeofOnArrayDecay(*this, BO->getOperatorLoc(), BO->getType(),
3611 BO->getLHS());
3612 warnOnSizeofOnArrayDecay(*this, BO->getOperatorLoc(), BO->getType(),
3613 BO->getRHS());
3614 }
3615 }
3616
3617 return false;
3618 }
3619
3620 /// \brief Check the constraints on operands to unary expression and type
3621 /// traits.
3622 ///
3623 /// This will complete any types necessary, and validate the various constraints
3624 /// on those operands.
3625 ///
3626 /// The UsualUnaryConversions() function is *not* called by this routine.
3627 /// C99 6.3.2.1p[2-4] all state:
3628 /// Except when it is the operand of the sizeof operator ...
3629 ///
3630 /// C++ [expr.sizeof]p4
3631 /// The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
3632 /// standard conversions are not applied to the operand of sizeof.
3633 ///
3634 /// This policy is followed for all of the unary trait expressions.
CheckUnaryExprOrTypeTraitOperand(QualType ExprType,SourceLocation OpLoc,SourceRange ExprRange,UnaryExprOrTypeTrait ExprKind)3635 bool Sema::CheckUnaryExprOrTypeTraitOperand(QualType ExprType,
3636 SourceLocation OpLoc,
3637 SourceRange ExprRange,
3638 UnaryExprOrTypeTrait ExprKind) {
3639 if (ExprType->isDependentType())
3640 return false;
3641
3642 // C++ [expr.sizeof]p2:
3643 // When applied to a reference or a reference type, the result
3644 // is the size of the referenced type.
3645 // C++11 [expr.alignof]p3:
3646 // When alignof is applied to a reference type, the result
3647 // shall be the alignment of the referenced type.
3648 if (const ReferenceType *Ref = ExprType->getAs<ReferenceType>())
3649 ExprType = Ref->getPointeeType();
3650
3651 // C11 6.5.3.4/3, C++11 [expr.alignof]p3:
3652 // When alignof or _Alignof is applied to an array type, the result
3653 // is the alignment of the element type.
3654 if (ExprKind == UETT_AlignOf || ExprKind == UETT_OpenMPRequiredSimdAlign)
3655 ExprType = Context.getBaseElementType(ExprType);
3656
3657 if (ExprKind == UETT_VecStep)
3658 return CheckVecStepTraitOperandType(*this, ExprType, OpLoc, ExprRange);
3659
3660 // Whitelist some types as extensions
3661 if (!CheckExtensionTraitOperandType(*this, ExprType, OpLoc, ExprRange,
3662 ExprKind))
3663 return false;
3664
3665 if (RequireCompleteType(OpLoc, ExprType,
3666 diag::err_sizeof_alignof_incomplete_type,
3667 ExprKind, ExprRange))
3668 return true;
3669
3670 if (ExprType->isFunctionType()) {
3671 Diag(OpLoc, diag::err_sizeof_alignof_function_type)
3672 << ExprKind << ExprRange;
3673 return true;
3674 }
3675
3676 if (CheckObjCTraitOperandConstraints(*this, ExprType, OpLoc, ExprRange,
3677 ExprKind))
3678 return true;
3679
3680 return false;
3681 }
3682
CheckAlignOfExpr(Sema & S,Expr * E)3683 static bool CheckAlignOfExpr(Sema &S, Expr *E) {
3684 E = E->IgnoreParens();
3685
3686 // Cannot know anything else if the expression is dependent.
3687 if (E->isTypeDependent())
3688 return false;
3689
3690 if (E->getObjectKind() == OK_BitField) {
3691 S.Diag(E->getExprLoc(), diag::err_sizeof_alignof_typeof_bitfield)
3692 << 1 << E->getSourceRange();
3693 return true;
3694 }
3695
3696 ValueDecl *D = nullptr;
3697 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
3698 D = DRE->getDecl();
3699 } else if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
3700 D = ME->getMemberDecl();
3701 }
3702
3703 // If it's a field, require the containing struct to have a
3704 // complete definition so that we can compute the layout.
3705 //
3706 // This can happen in C++11 onwards, either by naming the member
3707 // in a way that is not transformed into a member access expression
3708 // (in an unevaluated operand, for instance), or by naming the member
3709 // in a trailing-return-type.
3710 //
3711 // For the record, since __alignof__ on expressions is a GCC
3712 // extension, GCC seems to permit this but always gives the
3713 // nonsensical answer 0.
3714 //
3715 // We don't really need the layout here --- we could instead just
3716 // directly check for all the appropriate alignment-lowing
3717 // attributes --- but that would require duplicating a lot of
3718 // logic that just isn't worth duplicating for such a marginal
3719 // use-case.
3720 if (FieldDecl *FD = dyn_cast_or_null<FieldDecl>(D)) {
3721 // Fast path this check, since we at least know the record has a
3722 // definition if we can find a member of it.
3723 if (!FD->getParent()->isCompleteDefinition()) {
3724 S.Diag(E->getExprLoc(), diag::err_alignof_member_of_incomplete_type)
3725 << E->getSourceRange();
3726 return true;
3727 }
3728
3729 // Otherwise, if it's a field, and the field doesn't have
3730 // reference type, then it must have a complete type (or be a
3731 // flexible array member, which we explicitly want to
3732 // white-list anyway), which makes the following checks trivial.
3733 if (!FD->getType()->isReferenceType())
3734 return false;
3735 }
3736
3737 return S.CheckUnaryExprOrTypeTraitOperand(E, UETT_AlignOf);
3738 }
3739
CheckVecStepExpr(Expr * E)3740 bool Sema::CheckVecStepExpr(Expr *E) {
3741 E = E->IgnoreParens();
3742
3743 // Cannot know anything else if the expression is dependent.
3744 if (E->isTypeDependent())
3745 return false;
3746
3747 return CheckUnaryExprOrTypeTraitOperand(E, UETT_VecStep);
3748 }
3749
3750 /// \brief Build a sizeof or alignof expression given a type operand.
3751 ExprResult
CreateUnaryExprOrTypeTraitExpr(TypeSourceInfo * TInfo,SourceLocation OpLoc,UnaryExprOrTypeTrait ExprKind,SourceRange R)3752 Sema::CreateUnaryExprOrTypeTraitExpr(TypeSourceInfo *TInfo,
3753 SourceLocation OpLoc,
3754 UnaryExprOrTypeTrait ExprKind,
3755 SourceRange R) {
3756 if (!TInfo)
3757 return ExprError();
3758
3759 QualType T = TInfo->getType();
3760
3761 if (!T->isDependentType() &&
3762 CheckUnaryExprOrTypeTraitOperand(T, OpLoc, R, ExprKind))
3763 return ExprError();
3764
3765 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t.
3766 return new (Context) UnaryExprOrTypeTraitExpr(
3767 ExprKind, TInfo, Context.getSizeType(), OpLoc, R.getEnd());
3768 }
3769
3770 /// \brief Build a sizeof or alignof expression given an expression
3771 /// operand.
3772 ExprResult
CreateUnaryExprOrTypeTraitExpr(Expr * E,SourceLocation OpLoc,UnaryExprOrTypeTrait ExprKind)3773 Sema::CreateUnaryExprOrTypeTraitExpr(Expr *E, SourceLocation OpLoc,
3774 UnaryExprOrTypeTrait ExprKind) {
3775 ExprResult PE = CheckPlaceholderExpr(E);
3776 if (PE.isInvalid())
3777 return ExprError();
3778
3779 E = PE.get();
3780
3781 // Verify that the operand is valid.
3782 bool isInvalid = false;
3783 if (E->isTypeDependent()) {
3784 // Delay type-checking for type-dependent expressions.
3785 } else if (ExprKind == UETT_AlignOf) {
3786 isInvalid = CheckAlignOfExpr(*this, E);
3787 } else if (ExprKind == UETT_VecStep) {
3788 isInvalid = CheckVecStepExpr(E);
3789 } else if (ExprKind == UETT_OpenMPRequiredSimdAlign) {
3790 Diag(E->getExprLoc(), diag::err_openmp_default_simd_align_expr);
3791 isInvalid = true;
3792 } else if (E->refersToBitField()) { // C99 6.5.3.4p1.
3793 Diag(E->getExprLoc(), diag::err_sizeof_alignof_typeof_bitfield) << 0;
3794 isInvalid = true;
3795 } else {
3796 isInvalid = CheckUnaryExprOrTypeTraitOperand(E, UETT_SizeOf);
3797 }
3798
3799 if (isInvalid)
3800 return ExprError();
3801
3802 if (ExprKind == UETT_SizeOf && E->getType()->isVariableArrayType()) {
3803 PE = TransformToPotentiallyEvaluated(E);
3804 if (PE.isInvalid()) return ExprError();
3805 E = PE.get();
3806 }
3807
3808 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t.
3809 return new (Context) UnaryExprOrTypeTraitExpr(
3810 ExprKind, E, Context.getSizeType(), OpLoc, E->getSourceRange().getEnd());
3811 }
3812
3813 /// ActOnUnaryExprOrTypeTraitExpr - Handle @c sizeof(type) and @c sizeof @c
3814 /// expr and the same for @c alignof and @c __alignof
3815 /// Note that the ArgRange is invalid if isType is false.
3816 ExprResult
ActOnUnaryExprOrTypeTraitExpr(SourceLocation OpLoc,UnaryExprOrTypeTrait ExprKind,bool IsType,void * TyOrEx,SourceRange ArgRange)3817 Sema::ActOnUnaryExprOrTypeTraitExpr(SourceLocation OpLoc,
3818 UnaryExprOrTypeTrait ExprKind, bool IsType,
3819 void *TyOrEx, SourceRange ArgRange) {
3820 // If error parsing type, ignore.
3821 if (!TyOrEx) return ExprError();
3822
3823 if (IsType) {
3824 TypeSourceInfo *TInfo;
3825 (void) GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrEx), &TInfo);
3826 return CreateUnaryExprOrTypeTraitExpr(TInfo, OpLoc, ExprKind, ArgRange);
3827 }
3828
3829 Expr *ArgEx = (Expr *)TyOrEx;
3830 ExprResult Result = CreateUnaryExprOrTypeTraitExpr(ArgEx, OpLoc, ExprKind);
3831 return Result;
3832 }
3833
CheckRealImagOperand(Sema & S,ExprResult & V,SourceLocation Loc,bool IsReal)3834 static QualType CheckRealImagOperand(Sema &S, ExprResult &V, SourceLocation Loc,
3835 bool IsReal) {
3836 if (V.get()->isTypeDependent())
3837 return S.Context.DependentTy;
3838
3839 // _Real and _Imag are only l-values for normal l-values.
3840 if (V.get()->getObjectKind() != OK_Ordinary) {
3841 V = S.DefaultLvalueConversion(V.get());
3842 if (V.isInvalid())
3843 return QualType();
3844 }
3845
3846 // These operators return the element type of a complex type.
3847 if (const ComplexType *CT = V.get()->getType()->getAs<ComplexType>())
3848 return CT->getElementType();
3849
3850 // Otherwise they pass through real integer and floating point types here.
3851 if (V.get()->getType()->isArithmeticType())
3852 return V.get()->getType();
3853
3854 // Test for placeholders.
3855 ExprResult PR = S.CheckPlaceholderExpr(V.get());
3856 if (PR.isInvalid()) return QualType();
3857 if (PR.get() != V.get()) {
3858 V = PR;
3859 return CheckRealImagOperand(S, V, Loc, IsReal);
3860 }
3861
3862 // Reject anything else.
3863 S.Diag(Loc, diag::err_realimag_invalid_type) << V.get()->getType()
3864 << (IsReal ? "__real" : "__imag");
3865 return QualType();
3866 }
3867
3868
3869
3870 ExprResult
ActOnPostfixUnaryOp(Scope * S,SourceLocation OpLoc,tok::TokenKind Kind,Expr * Input)3871 Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc,
3872 tok::TokenKind Kind, Expr *Input) {
3873 UnaryOperatorKind Opc;
3874 switch (Kind) {
3875 default: llvm_unreachable("Unknown unary op!");
3876 case tok::plusplus: Opc = UO_PostInc; break;
3877 case tok::minusminus: Opc = UO_PostDec; break;
3878 }
3879
3880 // Since this might is a postfix expression, get rid of ParenListExprs.
3881 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Input);
3882 if (Result.isInvalid()) return ExprError();
3883 Input = Result.get();
3884
3885 return BuildUnaryOp(S, OpLoc, Opc, Input);
3886 }
3887
3888 /// \brief Diagnose if arithmetic on the given ObjC pointer is illegal.
3889 ///
3890 /// \return true on error
checkArithmeticOnObjCPointer(Sema & S,SourceLocation opLoc,Expr * op)3891 static bool checkArithmeticOnObjCPointer(Sema &S,
3892 SourceLocation opLoc,
3893 Expr *op) {
3894 assert(op->getType()->isObjCObjectPointerType());
3895 if (S.LangOpts.ObjCRuntime.allowsPointerArithmetic() &&
3896 !S.LangOpts.ObjCSubscriptingLegacyRuntime)
3897 return false;
3898
3899 S.Diag(opLoc, diag::err_arithmetic_nonfragile_interface)
3900 << op->getType()->castAs<ObjCObjectPointerType>()->getPointeeType()
3901 << op->getSourceRange();
3902 return true;
3903 }
3904
isMSPropertySubscriptExpr(Sema & S,Expr * Base)3905 static bool isMSPropertySubscriptExpr(Sema &S, Expr *Base) {
3906 auto *BaseNoParens = Base->IgnoreParens();
3907 if (auto *MSProp = dyn_cast<MSPropertyRefExpr>(BaseNoParens))
3908 return MSProp->getPropertyDecl()->getType()->isArrayType();
3909 return isa<MSPropertySubscriptExpr>(BaseNoParens);
3910 }
3911
3912 ExprResult
ActOnArraySubscriptExpr(Scope * S,Expr * base,SourceLocation lbLoc,Expr * idx,SourceLocation rbLoc)3913 Sema::ActOnArraySubscriptExpr(Scope *S, Expr *base, SourceLocation lbLoc,
3914 Expr *idx, SourceLocation rbLoc) {
3915 if (base && !base->getType().isNull() &&
3916 base->getType()->isSpecificPlaceholderType(BuiltinType::OMPArraySection))
3917 return ActOnOMPArraySectionExpr(base, lbLoc, idx, SourceLocation(),
3918 /*Length=*/nullptr, rbLoc);
3919
3920 // Since this might be a postfix expression, get rid of ParenListExprs.
3921 if (isa<ParenListExpr>(base)) {
3922 ExprResult result = MaybeConvertParenListExprToParenExpr(S, base);
3923 if (result.isInvalid()) return ExprError();
3924 base = result.get();
3925 }
3926
3927 // Handle any non-overload placeholder types in the base and index
3928 // expressions. We can't handle overloads here because the other
3929 // operand might be an overloadable type, in which case the overload
3930 // resolution for the operator overload should get the first crack
3931 // at the overload.
3932 bool IsMSPropertySubscript = false;
3933 if (base->getType()->isNonOverloadPlaceholderType()) {
3934 IsMSPropertySubscript = isMSPropertySubscriptExpr(*this, base);
3935 if (!IsMSPropertySubscript) {
3936 ExprResult result = CheckPlaceholderExpr(base);
3937 if (result.isInvalid())
3938 return ExprError();
3939 base = result.get();
3940 }
3941 }
3942 if (idx->getType()->isNonOverloadPlaceholderType()) {
3943 ExprResult result = CheckPlaceholderExpr(idx);
3944 if (result.isInvalid()) return ExprError();
3945 idx = result.get();
3946 }
3947
3948 // Build an unanalyzed expression if either operand is type-dependent.
3949 if (getLangOpts().CPlusPlus &&
3950 (base->isTypeDependent() || idx->isTypeDependent())) {
3951 return new (Context) ArraySubscriptExpr(base, idx, Context.DependentTy,
3952 VK_LValue, OK_Ordinary, rbLoc);
3953 }
3954
3955 // MSDN, property (C++)
3956 // https://msdn.microsoft.com/en-us/library/yhfk0thd(v=vs.120).aspx
3957 // This attribute can also be used in the declaration of an empty array in a
3958 // class or structure definition. For example:
3959 // __declspec(property(get=GetX, put=PutX)) int x[];
3960 // The above statement indicates that x[] can be used with one or more array
3961 // indices. In this case, i=p->x[a][b] will be turned into i=p->GetX(a, b),
3962 // and p->x[a][b] = i will be turned into p->PutX(a, b, i);
3963 if (IsMSPropertySubscript) {
3964 // Build MS property subscript expression if base is MS property reference
3965 // or MS property subscript.
3966 return new (Context) MSPropertySubscriptExpr(
3967 base, idx, Context.PseudoObjectTy, VK_LValue, OK_Ordinary, rbLoc);
3968 }
3969
3970 // Use C++ overloaded-operator rules if either operand has record
3971 // type. The spec says to do this if either type is *overloadable*,
3972 // but enum types can't declare subscript operators or conversion
3973 // operators, so there's nothing interesting for overload resolution
3974 // to do if there aren't any record types involved.
3975 //
3976 // ObjC pointers have their own subscripting logic that is not tied
3977 // to overload resolution and so should not take this path.
3978 if (getLangOpts().CPlusPlus &&
3979 (base->getType()->isRecordType() ||
3980 (!base->getType()->isObjCObjectPointerType() &&
3981 idx->getType()->isRecordType()))) {
3982 return CreateOverloadedArraySubscriptExpr(lbLoc, rbLoc, base, idx);
3983 }
3984
3985 return CreateBuiltinArraySubscriptExpr(base, lbLoc, idx, rbLoc);
3986 }
3987
ActOnOMPArraySectionExpr(Expr * Base,SourceLocation LBLoc,Expr * LowerBound,SourceLocation ColonLoc,Expr * Length,SourceLocation RBLoc)3988 ExprResult Sema::ActOnOMPArraySectionExpr(Expr *Base, SourceLocation LBLoc,
3989 Expr *LowerBound,
3990 SourceLocation ColonLoc, Expr *Length,
3991 SourceLocation RBLoc) {
3992 if (Base->getType()->isPlaceholderType() &&
3993 !Base->getType()->isSpecificPlaceholderType(
3994 BuiltinType::OMPArraySection)) {
3995 ExprResult Result = CheckPlaceholderExpr(Base);
3996 if (Result.isInvalid())
3997 return ExprError();
3998 Base = Result.get();
3999 }
4000 if (LowerBound && LowerBound->getType()->isNonOverloadPlaceholderType()) {
4001 ExprResult Result = CheckPlaceholderExpr(LowerBound);
4002 if (Result.isInvalid())
4003 return ExprError();
4004 LowerBound = Result.get();
4005 }
4006 if (Length && Length->getType()->isNonOverloadPlaceholderType()) {
4007 ExprResult Result = CheckPlaceholderExpr(Length);
4008 if (Result.isInvalid())
4009 return ExprError();
4010 Length = Result.get();
4011 }
4012
4013 // Build an unanalyzed expression if either operand is type-dependent.
4014 if (Base->isTypeDependent() ||
4015 (LowerBound &&
4016 (LowerBound->isTypeDependent() || LowerBound->isValueDependent())) ||
4017 (Length && (Length->isTypeDependent() || Length->isValueDependent()))) {
4018 return new (Context)
4019 OMPArraySectionExpr(Base, LowerBound, Length, Context.DependentTy,
4020 VK_LValue, OK_Ordinary, ColonLoc, RBLoc);
4021 }
4022
4023 // Perform default conversions.
4024 QualType OriginalTy = OMPArraySectionExpr::getBaseOriginalType(Base);
4025 QualType ResultTy;
4026 if (OriginalTy->isAnyPointerType()) {
4027 ResultTy = OriginalTy->getPointeeType();
4028 } else if (OriginalTy->isArrayType()) {
4029 ResultTy = OriginalTy->getAsArrayTypeUnsafe()->getElementType();
4030 } else {
4031 return ExprError(
4032 Diag(Base->getExprLoc(), diag::err_omp_typecheck_section_value)
4033 << Base->getSourceRange());
4034 }
4035 // C99 6.5.2.1p1
4036 if (LowerBound) {
4037 auto Res = PerformOpenMPImplicitIntegerConversion(LowerBound->getExprLoc(),
4038 LowerBound);
4039 if (Res.isInvalid())
4040 return ExprError(Diag(LowerBound->getExprLoc(),
4041 diag::err_omp_typecheck_section_not_integer)
4042 << 0 << LowerBound->getSourceRange());
4043 LowerBound = Res.get();
4044
4045 if (LowerBound->getType()->isSpecificBuiltinType(BuiltinType::Char_S) ||
4046 LowerBound->getType()->isSpecificBuiltinType(BuiltinType::Char_U))
4047 Diag(LowerBound->getExprLoc(), diag::warn_omp_section_is_char)
4048 << 0 << LowerBound->getSourceRange();
4049 }
4050 if (Length) {
4051 auto Res =
4052 PerformOpenMPImplicitIntegerConversion(Length->getExprLoc(), Length);
4053 if (Res.isInvalid())
4054 return ExprError(Diag(Length->getExprLoc(),
4055 diag::err_omp_typecheck_section_not_integer)
4056 << 1 << Length->getSourceRange());
4057 Length = Res.get();
4058
4059 if (Length->getType()->isSpecificBuiltinType(BuiltinType::Char_S) ||
4060 Length->getType()->isSpecificBuiltinType(BuiltinType::Char_U))
4061 Diag(Length->getExprLoc(), diag::warn_omp_section_is_char)
4062 << 1 << Length->getSourceRange();
4063 }
4064
4065 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly,
4066 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object
4067 // type. Note that functions are not objects, and that (in C99 parlance)
4068 // incomplete types are not object types.
4069 if (ResultTy->isFunctionType()) {
4070 Diag(Base->getExprLoc(), diag::err_omp_section_function_type)
4071 << ResultTy << Base->getSourceRange();
4072 return ExprError();
4073 }
4074
4075 if (RequireCompleteType(Base->getExprLoc(), ResultTy,
4076 diag::err_omp_section_incomplete_type, Base))
4077 return ExprError();
4078
4079 if (LowerBound) {
4080 llvm::APSInt LowerBoundValue;
4081 if (LowerBound->EvaluateAsInt(LowerBoundValue, Context)) {
4082 // OpenMP 4.0, [2.4 Array Sections]
4083 // The lower-bound and length must evaluate to non-negative integers.
4084 if (LowerBoundValue.isNegative()) {
4085 Diag(LowerBound->getExprLoc(), diag::err_omp_section_negative)
4086 << 0 << LowerBoundValue.toString(/*Radix=*/10, /*Signed=*/true)
4087 << LowerBound->getSourceRange();
4088 return ExprError();
4089 }
4090 }
4091 }
4092
4093 if (Length) {
4094 llvm::APSInt LengthValue;
4095 if (Length->EvaluateAsInt(LengthValue, Context)) {
4096 // OpenMP 4.0, [2.4 Array Sections]
4097 // The lower-bound and length must evaluate to non-negative integers.
4098 if (LengthValue.isNegative()) {
4099 Diag(Length->getExprLoc(), diag::err_omp_section_negative)
4100 << 1 << LengthValue.toString(/*Radix=*/10, /*Signed=*/true)
4101 << Length->getSourceRange();
4102 return ExprError();
4103 }
4104 }
4105 } else if (ColonLoc.isValid() &&
4106 (OriginalTy.isNull() || (!OriginalTy->isConstantArrayType() &&
4107 !OriginalTy->isVariableArrayType()))) {
4108 // OpenMP 4.0, [2.4 Array Sections]
4109 // When the size of the array dimension is not known, the length must be
4110 // specified explicitly.
4111 Diag(ColonLoc, diag::err_omp_section_length_undefined)
4112 << (!OriginalTy.isNull() && OriginalTy->isArrayType());
4113 return ExprError();
4114 }
4115
4116 return new (Context)
4117 OMPArraySectionExpr(Base, LowerBound, Length, Context.OMPArraySectionTy,
4118 VK_LValue, OK_Ordinary, ColonLoc, RBLoc);
4119 }
4120
4121 ExprResult
CreateBuiltinArraySubscriptExpr(Expr * Base,SourceLocation LLoc,Expr * Idx,SourceLocation RLoc)4122 Sema::CreateBuiltinArraySubscriptExpr(Expr *Base, SourceLocation LLoc,
4123 Expr *Idx, SourceLocation RLoc) {
4124 Expr *LHSExp = Base;
4125 Expr *RHSExp = Idx;
4126
4127 // Perform default conversions.
4128 if (!LHSExp->getType()->getAs<VectorType>()) {
4129 ExprResult Result = DefaultFunctionArrayLvalueConversion(LHSExp);
4130 if (Result.isInvalid())
4131 return ExprError();
4132 LHSExp = Result.get();
4133 }
4134 ExprResult Result = DefaultFunctionArrayLvalueConversion(RHSExp);
4135 if (Result.isInvalid())
4136 return ExprError();
4137 RHSExp = Result.get();
4138
4139 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType();
4140 ExprValueKind VK = VK_LValue;
4141 ExprObjectKind OK = OK_Ordinary;
4142
4143 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent
4144 // to the expression *((e1)+(e2)). This means the array "Base" may actually be
4145 // in the subscript position. As a result, we need to derive the array base
4146 // and index from the expression types.
4147 Expr *BaseExpr, *IndexExpr;
4148 QualType ResultType;
4149 if (LHSTy->isDependentType() || RHSTy->isDependentType()) {
4150 BaseExpr = LHSExp;
4151 IndexExpr = RHSExp;
4152 ResultType = Context.DependentTy;
4153 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) {
4154 BaseExpr = LHSExp;
4155 IndexExpr = RHSExp;
4156 ResultType = PTy->getPointeeType();
4157 } else if (const ObjCObjectPointerType *PTy =
4158 LHSTy->getAs<ObjCObjectPointerType>()) {
4159 BaseExpr = LHSExp;
4160 IndexExpr = RHSExp;
4161
4162 // Use custom logic if this should be the pseudo-object subscript
4163 // expression.
4164 if (!LangOpts.isSubscriptPointerArithmetic())
4165 return BuildObjCSubscriptExpression(RLoc, BaseExpr, IndexExpr, nullptr,
4166 nullptr);
4167
4168 ResultType = PTy->getPointeeType();
4169 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) {
4170 // Handle the uncommon case of "123[Ptr]".
4171 BaseExpr = RHSExp;
4172 IndexExpr = LHSExp;
4173 ResultType = PTy->getPointeeType();
4174 } else if (const ObjCObjectPointerType *PTy =
4175 RHSTy->getAs<ObjCObjectPointerType>()) {
4176 // Handle the uncommon case of "123[Ptr]".
4177 BaseExpr = RHSExp;
4178 IndexExpr = LHSExp;
4179 ResultType = PTy->getPointeeType();
4180 if (!LangOpts.isSubscriptPointerArithmetic()) {
4181 Diag(LLoc, diag::err_subscript_nonfragile_interface)
4182 << ResultType << BaseExpr->getSourceRange();
4183 return ExprError();
4184 }
4185 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) {
4186 BaseExpr = LHSExp; // vectors: V[123]
4187 IndexExpr = RHSExp;
4188 VK = LHSExp->getValueKind();
4189 if (VK != VK_RValue)
4190 OK = OK_VectorComponent;
4191
4192 // FIXME: need to deal with const...
4193 ResultType = VTy->getElementType();
4194 } else if (LHSTy->isArrayType()) {
4195 // If we see an array that wasn't promoted by
4196 // DefaultFunctionArrayLvalueConversion, it must be an array that
4197 // wasn't promoted because of the C90 rule that doesn't
4198 // allow promoting non-lvalue arrays. Warn, then
4199 // force the promotion here.
4200 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) <<
4201 LHSExp->getSourceRange();
4202 LHSExp = ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy),
4203 CK_ArrayToPointerDecay).get();
4204 LHSTy = LHSExp->getType();
4205
4206 BaseExpr = LHSExp;
4207 IndexExpr = RHSExp;
4208 ResultType = LHSTy->getAs<PointerType>()->getPointeeType();
4209 } else if (RHSTy->isArrayType()) {
4210 // Same as previous, except for 123[f().a] case
4211 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) <<
4212 RHSExp->getSourceRange();
4213 RHSExp = ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy),
4214 CK_ArrayToPointerDecay).get();
4215 RHSTy = RHSExp->getType();
4216
4217 BaseExpr = RHSExp;
4218 IndexExpr = LHSExp;
4219 ResultType = RHSTy->getAs<PointerType>()->getPointeeType();
4220 } else {
4221 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value)
4222 << LHSExp->getSourceRange() << RHSExp->getSourceRange());
4223 }
4224 // C99 6.5.2.1p1
4225 if (!IndexExpr->getType()->isIntegerType() && !IndexExpr->isTypeDependent())
4226 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer)
4227 << IndexExpr->getSourceRange());
4228
4229 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) ||
4230 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U))
4231 && !IndexExpr->isTypeDependent())
4232 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange();
4233
4234 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly,
4235 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object
4236 // type. Note that Functions are not objects, and that (in C99 parlance)
4237 // incomplete types are not object types.
4238 if (ResultType->isFunctionType()) {
4239 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type)
4240 << ResultType << BaseExpr->getSourceRange();
4241 return ExprError();
4242 }
4243
4244 if (ResultType->isVoidType() && !getLangOpts().CPlusPlus) {
4245 // GNU extension: subscripting on pointer to void
4246 Diag(LLoc, diag::ext_gnu_subscript_void_type)
4247 << BaseExpr->getSourceRange();
4248
4249 // C forbids expressions of unqualified void type from being l-values.
4250 // See IsCForbiddenLValueType.
4251 if (!ResultType.hasQualifiers()) VK = VK_RValue;
4252 } else if (!ResultType->isDependentType() &&
4253 RequireCompleteType(LLoc, ResultType,
4254 diag::err_subscript_incomplete_type, BaseExpr))
4255 return ExprError();
4256
4257 assert(VK == VK_RValue || LangOpts.CPlusPlus ||
4258 !ResultType.isCForbiddenLValueType());
4259
4260 return new (Context)
4261 ArraySubscriptExpr(LHSExp, RHSExp, ResultType, VK, OK, RLoc);
4262 }
4263
BuildCXXDefaultArgExpr(SourceLocation CallLoc,FunctionDecl * FD,ParmVarDecl * Param)4264 ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc,
4265 FunctionDecl *FD,
4266 ParmVarDecl *Param) {
4267 if (Param->hasUnparsedDefaultArg()) {
4268 Diag(CallLoc,
4269 diag::err_use_of_default_argument_to_function_declared_later) <<
4270 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName();
4271 Diag(UnparsedDefaultArgLocs[Param],
4272 diag::note_default_argument_declared_here);
4273 return ExprError();
4274 }
4275
4276 if (Param->hasUninstantiatedDefaultArg()) {
4277 Expr *UninstExpr = Param->getUninstantiatedDefaultArg();
4278
4279 EnterExpressionEvaluationContext EvalContext(*this, PotentiallyEvaluated,
4280 Param);
4281
4282 // Instantiate the expression.
4283 MultiLevelTemplateArgumentList MutiLevelArgList
4284 = getTemplateInstantiationArgs(FD, nullptr, /*RelativeToPrimary=*/true);
4285
4286 InstantiatingTemplate Inst(*this, CallLoc, Param,
4287 MutiLevelArgList.getInnermost());
4288 if (Inst.isInvalid())
4289 return ExprError();
4290
4291 ExprResult Result;
4292 {
4293 // C++ [dcl.fct.default]p5:
4294 // The names in the [default argument] expression are bound, and
4295 // the semantic constraints are checked, at the point where the
4296 // default argument expression appears.
4297 ContextRAII SavedContext(*this, FD);
4298 LocalInstantiationScope Local(*this);
4299 Result = SubstExpr(UninstExpr, MutiLevelArgList);
4300 }
4301 if (Result.isInvalid())
4302 return ExprError();
4303
4304 // Check the expression as an initializer for the parameter.
4305 InitializedEntity Entity
4306 = InitializedEntity::InitializeParameter(Context, Param);
4307 InitializationKind Kind
4308 = InitializationKind::CreateCopy(Param->getLocation(),
4309 /*FIXME:EqualLoc*/UninstExpr->getLocStart());
4310 Expr *ResultE = Result.getAs<Expr>();
4311
4312 InitializationSequence InitSeq(*this, Entity, Kind, ResultE);
4313 Result = InitSeq.Perform(*this, Entity, Kind, ResultE);
4314 if (Result.isInvalid())
4315 return ExprError();
4316
4317 Expr *Arg = Result.getAs<Expr>();
4318 CheckCompletedExpr(Arg, Param->getOuterLocStart());
4319 // Build the default argument expression.
4320 return CXXDefaultArgExpr::Create(Context, CallLoc, Param, Arg);
4321 }
4322
4323 // If the default expression creates temporaries, we need to
4324 // push them to the current stack of expression temporaries so they'll
4325 // be properly destroyed.
4326 // FIXME: We should really be rebuilding the default argument with new
4327 // bound temporaries; see the comment in PR5810.
4328 // We don't need to do that with block decls, though, because
4329 // blocks in default argument expression can never capture anything.
4330 if (isa<ExprWithCleanups>(Param->getInit())) {
4331 // Set the "needs cleanups" bit regardless of whether there are
4332 // any explicit objects.
4333 ExprNeedsCleanups = true;
4334
4335 // Append all the objects to the cleanup list. Right now, this
4336 // should always be a no-op, because blocks in default argument
4337 // expressions should never be able to capture anything.
4338 assert(!cast<ExprWithCleanups>(Param->getInit())->getNumObjects() &&
4339 "default argument expression has capturing blocks?");
4340 }
4341
4342 // We already type-checked the argument, so we know it works.
4343 // Just mark all of the declarations in this potentially-evaluated expression
4344 // as being "referenced".
4345 MarkDeclarationsReferencedInExpr(Param->getDefaultArg(),
4346 /*SkipLocalVariables=*/true);
4347 return CXXDefaultArgExpr::Create(Context, CallLoc, Param);
4348 }
4349
4350
4351 Sema::VariadicCallType
getVariadicCallType(FunctionDecl * FDecl,const FunctionProtoType * Proto,Expr * Fn)4352 Sema::getVariadicCallType(FunctionDecl *FDecl, const FunctionProtoType *Proto,
4353 Expr *Fn) {
4354 if (Proto && Proto->isVariadic()) {
4355 if (dyn_cast_or_null<CXXConstructorDecl>(FDecl))
4356 return VariadicConstructor;
4357 else if (Fn && Fn->getType()->isBlockPointerType())
4358 return VariadicBlock;
4359 else if (FDecl) {
4360 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl))
4361 if (Method->isInstance())
4362 return VariadicMethod;
4363 } else if (Fn && Fn->getType() == Context.BoundMemberTy)
4364 return VariadicMethod;
4365 return VariadicFunction;
4366 }
4367 return VariadicDoesNotApply;
4368 }
4369
4370 namespace {
4371 class FunctionCallCCC : public FunctionCallFilterCCC {
4372 public:
FunctionCallCCC(Sema & SemaRef,const IdentifierInfo * FuncName,unsigned NumArgs,MemberExpr * ME)4373 FunctionCallCCC(Sema &SemaRef, const IdentifierInfo *FuncName,
4374 unsigned NumArgs, MemberExpr *ME)
4375 : FunctionCallFilterCCC(SemaRef, NumArgs, false, ME),
4376 FunctionName(FuncName) {}
4377
ValidateCandidate(const TypoCorrection & candidate)4378 bool ValidateCandidate(const TypoCorrection &candidate) override {
4379 if (!candidate.getCorrectionSpecifier() ||
4380 candidate.getCorrectionAsIdentifierInfo() != FunctionName) {
4381 return false;
4382 }
4383
4384 return FunctionCallFilterCCC::ValidateCandidate(candidate);
4385 }
4386
4387 private:
4388 const IdentifierInfo *const FunctionName;
4389 };
4390 }
4391
TryTypoCorrectionForCall(Sema & S,Expr * Fn,FunctionDecl * FDecl,ArrayRef<Expr * > Args)4392 static TypoCorrection TryTypoCorrectionForCall(Sema &S, Expr *Fn,
4393 FunctionDecl *FDecl,
4394 ArrayRef<Expr *> Args) {
4395 MemberExpr *ME = dyn_cast<MemberExpr>(Fn);
4396 DeclarationName FuncName = FDecl->getDeclName();
4397 SourceLocation NameLoc = ME ? ME->getMemberLoc() : Fn->getLocStart();
4398
4399 if (TypoCorrection Corrected = S.CorrectTypo(
4400 DeclarationNameInfo(FuncName, NameLoc), Sema::LookupOrdinaryName,
4401 S.getScopeForContext(S.CurContext), nullptr,
4402 llvm::make_unique<FunctionCallCCC>(S, FuncName.getAsIdentifierInfo(),
4403 Args.size(), ME),
4404 Sema::CTK_ErrorRecovery)) {
4405 if (NamedDecl *ND = Corrected.getCorrectionDecl()) {
4406 if (Corrected.isOverloaded()) {
4407 OverloadCandidateSet OCS(NameLoc, OverloadCandidateSet::CSK_Normal);
4408 OverloadCandidateSet::iterator Best;
4409 for (NamedDecl *CD : Corrected) {
4410 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(CD))
4411 S.AddOverloadCandidate(FD, DeclAccessPair::make(FD, AS_none), Args,
4412 OCS);
4413 }
4414 switch (OCS.BestViableFunction(S, NameLoc, Best)) {
4415 case OR_Success:
4416 ND = Best->Function;
4417 Corrected.setCorrectionDecl(ND);
4418 break;
4419 default:
4420 break;
4421 }
4422 }
4423 if (isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND)) {
4424 return Corrected;
4425 }
4426 }
4427 }
4428 return TypoCorrection();
4429 }
4430
4431 /// ConvertArgumentsForCall - Converts the arguments specified in
4432 /// Args/NumArgs to the parameter types of the function FDecl with
4433 /// function prototype Proto. Call is the call expression itself, and
4434 /// Fn is the function expression. For a C++ member function, this
4435 /// routine does not attempt to convert the object argument. Returns
4436 /// true if the call is ill-formed.
4437 bool
ConvertArgumentsForCall(CallExpr * Call,Expr * Fn,FunctionDecl * FDecl,const FunctionProtoType * Proto,ArrayRef<Expr * > Args,SourceLocation RParenLoc,bool IsExecConfig)4438 Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn,
4439 FunctionDecl *FDecl,
4440 const FunctionProtoType *Proto,
4441 ArrayRef<Expr *> Args,
4442 SourceLocation RParenLoc,
4443 bool IsExecConfig) {
4444 // Bail out early if calling a builtin with custom typechecking.
4445 if (FDecl)
4446 if (unsigned ID = FDecl->getBuiltinID())
4447 if (Context.BuiltinInfo.hasCustomTypechecking(ID))
4448 return false;
4449
4450 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by
4451 // assignment, to the types of the corresponding parameter, ...
4452 unsigned NumParams = Proto->getNumParams();
4453 bool Invalid = false;
4454 unsigned MinArgs = FDecl ? FDecl->getMinRequiredArguments() : NumParams;
4455 unsigned FnKind = Fn->getType()->isBlockPointerType()
4456 ? 1 /* block */
4457 : (IsExecConfig ? 3 /* kernel function (exec config) */
4458 : 0 /* function */);
4459
4460 // If too few arguments are available (and we don't have default
4461 // arguments for the remaining parameters), don't make the call.
4462 if (Args.size() < NumParams) {
4463 if (Args.size() < MinArgs) {
4464 TypoCorrection TC;
4465 if (FDecl && (TC = TryTypoCorrectionForCall(*this, Fn, FDecl, Args))) {
4466 unsigned diag_id =
4467 MinArgs == NumParams && !Proto->isVariadic()
4468 ? diag::err_typecheck_call_too_few_args_suggest
4469 : diag::err_typecheck_call_too_few_args_at_least_suggest;
4470 diagnoseTypo(TC, PDiag(diag_id) << FnKind << MinArgs
4471 << static_cast<unsigned>(Args.size())
4472 << TC.getCorrectionRange());
4473 } else if (MinArgs == 1 && FDecl && FDecl->getParamDecl(0)->getDeclName())
4474 Diag(RParenLoc,
4475 MinArgs == NumParams && !Proto->isVariadic()
4476 ? diag::err_typecheck_call_too_few_args_one
4477 : diag::err_typecheck_call_too_few_args_at_least_one)
4478 << FnKind << FDecl->getParamDecl(0) << Fn->getSourceRange();
4479 else
4480 Diag(RParenLoc, MinArgs == NumParams && !Proto->isVariadic()
4481 ? diag::err_typecheck_call_too_few_args
4482 : diag::err_typecheck_call_too_few_args_at_least)
4483 << FnKind << MinArgs << static_cast<unsigned>(Args.size())
4484 << Fn->getSourceRange();
4485
4486 // Emit the location of the prototype.
4487 if (!TC && FDecl && !FDecl->getBuiltinID() && !IsExecConfig)
4488 Diag(FDecl->getLocStart(), diag::note_callee_decl)
4489 << FDecl;
4490
4491 return true;
4492 }
4493 Call->setNumArgs(Context, NumParams);
4494 }
4495
4496 // If too many are passed and not variadic, error on the extras and drop
4497 // them.
4498 if (Args.size() > NumParams) {
4499 if (!Proto->isVariadic()) {
4500 TypoCorrection TC;
4501 if (FDecl && (TC = TryTypoCorrectionForCall(*this, Fn, FDecl, Args))) {
4502 unsigned diag_id =
4503 MinArgs == NumParams && !Proto->isVariadic()
4504 ? diag::err_typecheck_call_too_many_args_suggest
4505 : diag::err_typecheck_call_too_many_args_at_most_suggest;
4506 diagnoseTypo(TC, PDiag(diag_id) << FnKind << NumParams
4507 << static_cast<unsigned>(Args.size())
4508 << TC.getCorrectionRange());
4509 } else if (NumParams == 1 && FDecl &&
4510 FDecl->getParamDecl(0)->getDeclName())
4511 Diag(Args[NumParams]->getLocStart(),
4512 MinArgs == NumParams
4513 ? diag::err_typecheck_call_too_many_args_one
4514 : diag::err_typecheck_call_too_many_args_at_most_one)
4515 << FnKind << FDecl->getParamDecl(0)
4516 << static_cast<unsigned>(Args.size()) << Fn->getSourceRange()
4517 << SourceRange(Args[NumParams]->getLocStart(),
4518 Args.back()->getLocEnd());
4519 else
4520 Diag(Args[NumParams]->getLocStart(),
4521 MinArgs == NumParams
4522 ? diag::err_typecheck_call_too_many_args
4523 : diag::err_typecheck_call_too_many_args_at_most)
4524 << FnKind << NumParams << static_cast<unsigned>(Args.size())
4525 << Fn->getSourceRange()
4526 << SourceRange(Args[NumParams]->getLocStart(),
4527 Args.back()->getLocEnd());
4528
4529 // Emit the location of the prototype.
4530 if (!TC && FDecl && !FDecl->getBuiltinID() && !IsExecConfig)
4531 Diag(FDecl->getLocStart(), diag::note_callee_decl)
4532 << FDecl;
4533
4534 // This deletes the extra arguments.
4535 Call->setNumArgs(Context, NumParams);
4536 return true;
4537 }
4538 }
4539 SmallVector<Expr *, 8> AllArgs;
4540 VariadicCallType CallType = getVariadicCallType(FDecl, Proto, Fn);
4541
4542 Invalid = GatherArgumentsForCall(Call->getLocStart(), FDecl,
4543 Proto, 0, Args, AllArgs, CallType);
4544 if (Invalid)
4545 return true;
4546 unsigned TotalNumArgs = AllArgs.size();
4547 for (unsigned i = 0; i < TotalNumArgs; ++i)
4548 Call->setArg(i, AllArgs[i]);
4549
4550 return false;
4551 }
4552
GatherArgumentsForCall(SourceLocation CallLoc,FunctionDecl * FDecl,const FunctionProtoType * Proto,unsigned FirstParam,ArrayRef<Expr * > Args,SmallVectorImpl<Expr * > & AllArgs,VariadicCallType CallType,bool AllowExplicit,bool IsListInitialization)4553 bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, FunctionDecl *FDecl,
4554 const FunctionProtoType *Proto,
4555 unsigned FirstParam, ArrayRef<Expr *> Args,
4556 SmallVectorImpl<Expr *> &AllArgs,
4557 VariadicCallType CallType, bool AllowExplicit,
4558 bool IsListInitialization) {
4559 unsigned NumParams = Proto->getNumParams();
4560 bool Invalid = false;
4561 size_t ArgIx = 0;
4562 // Continue to check argument types (even if we have too few/many args).
4563 for (unsigned i = FirstParam; i < NumParams; i++) {
4564 QualType ProtoArgType = Proto->getParamType(i);
4565
4566 Expr *Arg;
4567 ParmVarDecl *Param = FDecl ? FDecl->getParamDecl(i) : nullptr;
4568 if (ArgIx < Args.size()) {
4569 Arg = Args[ArgIx++];
4570
4571 if (RequireCompleteType(Arg->getLocStart(),
4572 ProtoArgType,
4573 diag::err_call_incomplete_argument, Arg))
4574 return true;
4575
4576 // Strip the unbridged-cast placeholder expression off, if applicable.
4577 bool CFAudited = false;
4578 if (Arg->getType() == Context.ARCUnbridgedCastTy &&
4579 FDecl && FDecl->hasAttr<CFAuditedTransferAttr>() &&
4580 (!Param || !Param->hasAttr<CFConsumedAttr>()))
4581 Arg = stripARCUnbridgedCast(Arg);
4582 else if (getLangOpts().ObjCAutoRefCount &&
4583 FDecl && FDecl->hasAttr<CFAuditedTransferAttr>() &&
4584 (!Param || !Param->hasAttr<CFConsumedAttr>()))
4585 CFAudited = true;
4586
4587 InitializedEntity Entity =
4588 Param ? InitializedEntity::InitializeParameter(Context, Param,
4589 ProtoArgType)
4590 : InitializedEntity::InitializeParameter(
4591 Context, ProtoArgType, Proto->isParamConsumed(i));
4592
4593 // Remember that parameter belongs to a CF audited API.
4594 if (CFAudited)
4595 Entity.setParameterCFAudited();
4596
4597 ExprResult ArgE = PerformCopyInitialization(
4598 Entity, SourceLocation(), Arg, IsListInitialization, AllowExplicit);
4599 if (ArgE.isInvalid())
4600 return true;
4601
4602 Arg = ArgE.getAs<Expr>();
4603 } else {
4604 assert(Param && "can't use default arguments without a known callee");
4605
4606 ExprResult ArgExpr =
4607 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param);
4608 if (ArgExpr.isInvalid())
4609 return true;
4610
4611 Arg = ArgExpr.getAs<Expr>();
4612 }
4613
4614 // Check for array bounds violations for each argument to the call. This
4615 // check only triggers warnings when the argument isn't a more complex Expr
4616 // with its own checking, such as a BinaryOperator.
4617 CheckArrayAccess(Arg);
4618
4619 // Check for violations of C99 static array rules (C99 6.7.5.3p7).
4620 CheckStaticArrayArgument(CallLoc, Param, Arg);
4621
4622 AllArgs.push_back(Arg);
4623 }
4624
4625 // If this is a variadic call, handle args passed through "...".
4626 if (CallType != VariadicDoesNotApply) {
4627 // Assume that extern "C" functions with variadic arguments that
4628 // return __unknown_anytype aren't *really* variadic.
4629 if (Proto->getReturnType() == Context.UnknownAnyTy && FDecl &&
4630 FDecl->isExternC()) {
4631 for (Expr *A : Args.slice(ArgIx)) {
4632 QualType paramType; // ignored
4633 ExprResult arg = checkUnknownAnyArg(CallLoc, A, paramType);
4634 Invalid |= arg.isInvalid();
4635 AllArgs.push_back(arg.get());
4636 }
4637
4638 // Otherwise do argument promotion, (C99 6.5.2.2p7).
4639 } else {
4640 for (Expr *A : Args.slice(ArgIx)) {
4641 ExprResult Arg = DefaultVariadicArgumentPromotion(A, CallType, FDecl);
4642 Invalid |= Arg.isInvalid();
4643 AllArgs.push_back(Arg.get());
4644 }
4645 }
4646
4647 // Check for array bounds violations.
4648 for (Expr *A : Args.slice(ArgIx))
4649 CheckArrayAccess(A);
4650 }
4651 return Invalid;
4652 }
4653
DiagnoseCalleeStaticArrayParam(Sema & S,ParmVarDecl * PVD)4654 static void DiagnoseCalleeStaticArrayParam(Sema &S, ParmVarDecl *PVD) {
4655 TypeLoc TL = PVD->getTypeSourceInfo()->getTypeLoc();
4656 if (DecayedTypeLoc DTL = TL.getAs<DecayedTypeLoc>())
4657 TL = DTL.getOriginalLoc();
4658 if (ArrayTypeLoc ATL = TL.getAs<ArrayTypeLoc>())
4659 S.Diag(PVD->getLocation(), diag::note_callee_static_array)
4660 << ATL.getLocalSourceRange();
4661 }
4662
4663 /// CheckStaticArrayArgument - If the given argument corresponds to a static
4664 /// array parameter, check that it is non-null, and that if it is formed by
4665 /// array-to-pointer decay, the underlying array is sufficiently large.
4666 ///
4667 /// C99 6.7.5.3p7: If the keyword static also appears within the [ and ] of the
4668 /// array type derivation, then for each call to the function, the value of the
4669 /// corresponding actual argument shall provide access to the first element of
4670 /// an array with at least as many elements as specified by the size expression.
4671 void
CheckStaticArrayArgument(SourceLocation CallLoc,ParmVarDecl * Param,const Expr * ArgExpr)4672 Sema::CheckStaticArrayArgument(SourceLocation CallLoc,
4673 ParmVarDecl *Param,
4674 const Expr *ArgExpr) {
4675 // Static array parameters are not supported in C++.
4676 if (!Param || getLangOpts().CPlusPlus)
4677 return;
4678
4679 QualType OrigTy = Param->getOriginalType();
4680
4681 const ArrayType *AT = Context.getAsArrayType(OrigTy);
4682 if (!AT || AT->getSizeModifier() != ArrayType::Static)
4683 return;
4684
4685 if (ArgExpr->isNullPointerConstant(Context,
4686 Expr::NPC_NeverValueDependent)) {
4687 Diag(CallLoc, diag::warn_null_arg) << ArgExpr->getSourceRange();
4688 DiagnoseCalleeStaticArrayParam(*this, Param);
4689 return;
4690 }
4691
4692 const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT);
4693 if (!CAT)
4694 return;
4695
4696 const ConstantArrayType *ArgCAT =
4697 Context.getAsConstantArrayType(ArgExpr->IgnoreParenImpCasts()->getType());
4698 if (!ArgCAT)
4699 return;
4700
4701 if (ArgCAT->getSize().ult(CAT->getSize())) {
4702 Diag(CallLoc, diag::warn_static_array_too_small)
4703 << ArgExpr->getSourceRange()
4704 << (unsigned) ArgCAT->getSize().getZExtValue()
4705 << (unsigned) CAT->getSize().getZExtValue();
4706 DiagnoseCalleeStaticArrayParam(*this, Param);
4707 }
4708 }
4709
4710 /// Given a function expression of unknown-any type, try to rebuild it
4711 /// to have a function type.
4712 static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *fn);
4713
4714 /// Is the given type a placeholder that we need to lower out
4715 /// immediately during argument processing?
isPlaceholderToRemoveAsArg(QualType type)4716 static bool isPlaceholderToRemoveAsArg(QualType type) {
4717 // Placeholders are never sugared.
4718 const BuiltinType *placeholder = dyn_cast<BuiltinType>(type);
4719 if (!placeholder) return false;
4720
4721 switch (placeholder->getKind()) {
4722 // Ignore all the non-placeholder types.
4723 #define PLACEHOLDER_TYPE(ID, SINGLETON_ID)
4724 #define BUILTIN_TYPE(ID, SINGLETON_ID) case BuiltinType::ID:
4725 #include "clang/AST/BuiltinTypes.def"
4726 return false;
4727
4728 // We cannot lower out overload sets; they might validly be resolved
4729 // by the call machinery.
4730 case BuiltinType::Overload:
4731 return false;
4732
4733 // Unbridged casts in ARC can be handled in some call positions and
4734 // should be left in place.
4735 case BuiltinType::ARCUnbridgedCast:
4736 return false;
4737
4738 // Pseudo-objects should be converted as soon as possible.
4739 case BuiltinType::PseudoObject:
4740 return true;
4741
4742 // The debugger mode could theoretically but currently does not try
4743 // to resolve unknown-typed arguments based on known parameter types.
4744 case BuiltinType::UnknownAny:
4745 return true;
4746
4747 // These are always invalid as call arguments and should be reported.
4748 case BuiltinType::BoundMember:
4749 case BuiltinType::BuiltinFn:
4750 case BuiltinType::OMPArraySection:
4751 return true;
4752
4753 }
4754 llvm_unreachable("bad builtin type kind");
4755 }
4756
4757 /// Check an argument list for placeholders that we won't try to
4758 /// handle later.
checkArgsForPlaceholders(Sema & S,MultiExprArg args)4759 static bool checkArgsForPlaceholders(Sema &S, MultiExprArg args) {
4760 // Apply this processing to all the arguments at once instead of
4761 // dying at the first failure.
4762 bool hasInvalid = false;
4763 for (size_t i = 0, e = args.size(); i != e; i++) {
4764 if (isPlaceholderToRemoveAsArg(args[i]->getType())) {
4765 ExprResult result = S.CheckPlaceholderExpr(args[i]);
4766 if (result.isInvalid()) hasInvalid = true;
4767 else args[i] = result.get();
4768 } else if (hasInvalid) {
4769 (void)S.CorrectDelayedTyposInExpr(args[i]);
4770 }
4771 }
4772 return hasInvalid;
4773 }
4774
4775 /// If a builtin function has a pointer argument with no explicit address
4776 /// space, than it should be able to accept a pointer to any address
4777 /// space as input. In order to do this, we need to replace the
4778 /// standard builtin declaration with one that uses the same address space
4779 /// as the call.
4780 ///
4781 /// \returns nullptr If this builtin is not a candidate for a rewrite i.e.
4782 /// it does not contain any pointer arguments without
4783 /// an address space qualifer. Otherwise the rewritten
4784 /// FunctionDecl is returned.
4785 /// TODO: Handle pointer return types.
rewriteBuiltinFunctionDecl(Sema * Sema,ASTContext & Context,const FunctionDecl * FDecl,MultiExprArg ArgExprs)4786 static FunctionDecl *rewriteBuiltinFunctionDecl(Sema *Sema, ASTContext &Context,
4787 const FunctionDecl *FDecl,
4788 MultiExprArg ArgExprs) {
4789
4790 QualType DeclType = FDecl->getType();
4791 const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(DeclType);
4792
4793 if (!Context.BuiltinInfo.hasPtrArgsOrResult(FDecl->getBuiltinID()) ||
4794 !FT || FT->isVariadic() || ArgExprs.size() != FT->getNumParams())
4795 return nullptr;
4796
4797 bool NeedsNewDecl = false;
4798 unsigned i = 0;
4799 SmallVector<QualType, 8> OverloadParams;
4800
4801 for (QualType ParamType : FT->param_types()) {
4802
4803 // Convert array arguments to pointer to simplify type lookup.
4804 Expr *Arg = Sema->DefaultFunctionArrayLvalueConversion(ArgExprs[i++]).get();
4805 QualType ArgType = Arg->getType();
4806 if (!ParamType->isPointerType() ||
4807 ParamType.getQualifiers().hasAddressSpace() ||
4808 !ArgType->isPointerType() ||
4809 !ArgType->getPointeeType().getQualifiers().hasAddressSpace()) {
4810 OverloadParams.push_back(ParamType);
4811 continue;
4812 }
4813
4814 NeedsNewDecl = true;
4815 unsigned AS = ArgType->getPointeeType().getQualifiers().getAddressSpace();
4816
4817 QualType PointeeType = ParamType->getPointeeType();
4818 PointeeType = Context.getAddrSpaceQualType(PointeeType, AS);
4819 OverloadParams.push_back(Context.getPointerType(PointeeType));
4820 }
4821
4822 if (!NeedsNewDecl)
4823 return nullptr;
4824
4825 FunctionProtoType::ExtProtoInfo EPI;
4826 QualType OverloadTy = Context.getFunctionType(FT->getReturnType(),
4827 OverloadParams, EPI);
4828 DeclContext *Parent = Context.getTranslationUnitDecl();
4829 FunctionDecl *OverloadDecl = FunctionDecl::Create(Context, Parent,
4830 FDecl->getLocation(),
4831 FDecl->getLocation(),
4832 FDecl->getIdentifier(),
4833 OverloadTy,
4834 /*TInfo=*/nullptr,
4835 SC_Extern, false,
4836 /*hasPrototype=*/true);
4837 SmallVector<ParmVarDecl*, 16> Params;
4838 FT = cast<FunctionProtoType>(OverloadTy);
4839 for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
4840 QualType ParamType = FT->getParamType(i);
4841 ParmVarDecl *Parm =
4842 ParmVarDecl::Create(Context, OverloadDecl, SourceLocation(),
4843 SourceLocation(), nullptr, ParamType,
4844 /*TInfo=*/nullptr, SC_None, nullptr);
4845 Parm->setScopeInfo(0, i);
4846 Params.push_back(Parm);
4847 }
4848 OverloadDecl->setParams(Params);
4849 return OverloadDecl;
4850 }
4851
4852 /// ActOnCallExpr - Handle a call to Fn with the specified array of arguments.
4853 /// This provides the location of the left/right parens and a list of comma
4854 /// locations.
4855 ExprResult
ActOnCallExpr(Scope * S,Expr * Fn,SourceLocation LParenLoc,MultiExprArg ArgExprs,SourceLocation RParenLoc,Expr * ExecConfig,bool IsExecConfig)4856 Sema::ActOnCallExpr(Scope *S, Expr *Fn, SourceLocation LParenLoc,
4857 MultiExprArg ArgExprs, SourceLocation RParenLoc,
4858 Expr *ExecConfig, bool IsExecConfig) {
4859 // Since this might be a postfix expression, get rid of ParenListExprs.
4860 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Fn);
4861 if (Result.isInvalid()) return ExprError();
4862 Fn = Result.get();
4863
4864 if (checkArgsForPlaceholders(*this, ArgExprs))
4865 return ExprError();
4866
4867 if (getLangOpts().CPlusPlus) {
4868 // If this is a pseudo-destructor expression, build the call immediately.
4869 if (isa<CXXPseudoDestructorExpr>(Fn)) {
4870 if (!ArgExprs.empty()) {
4871 // Pseudo-destructor calls should not have any arguments.
4872 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args)
4873 << FixItHint::CreateRemoval(
4874 SourceRange(ArgExprs.front()->getLocStart(),
4875 ArgExprs.back()->getLocEnd()));
4876 }
4877
4878 return new (Context)
4879 CallExpr(Context, Fn, None, Context.VoidTy, VK_RValue, RParenLoc);
4880 }
4881 if (Fn->getType() == Context.PseudoObjectTy) {
4882 ExprResult result = CheckPlaceholderExpr(Fn);
4883 if (result.isInvalid()) return ExprError();
4884 Fn = result.get();
4885 }
4886
4887 // Determine whether this is a dependent call inside a C++ template,
4888 // in which case we won't do any semantic analysis now.
4889 // FIXME: Will need to cache the results of name lookup (including ADL) in
4890 // Fn.
4891 bool Dependent = false;
4892 if (Fn->isTypeDependent())
4893 Dependent = true;
4894 else if (Expr::hasAnyTypeDependentArguments(ArgExprs))
4895 Dependent = true;
4896
4897 if (Dependent) {
4898 if (ExecConfig) {
4899 return new (Context) CUDAKernelCallExpr(
4900 Context, Fn, cast<CallExpr>(ExecConfig), ArgExprs,
4901 Context.DependentTy, VK_RValue, RParenLoc);
4902 } else {
4903 return new (Context) CallExpr(
4904 Context, Fn, ArgExprs, Context.DependentTy, VK_RValue, RParenLoc);
4905 }
4906 }
4907
4908 // Determine whether this is a call to an object (C++ [over.call.object]).
4909 if (Fn->getType()->isRecordType())
4910 return BuildCallToObjectOfClassType(S, Fn, LParenLoc, ArgExprs,
4911 RParenLoc);
4912
4913 if (Fn->getType() == Context.UnknownAnyTy) {
4914 ExprResult result = rebuildUnknownAnyFunction(*this, Fn);
4915 if (result.isInvalid()) return ExprError();
4916 Fn = result.get();
4917 }
4918
4919 if (Fn->getType() == Context.BoundMemberTy) {
4920 return BuildCallToMemberFunction(S, Fn, LParenLoc, ArgExprs, RParenLoc);
4921 }
4922 }
4923
4924 // Check for overloaded calls. This can happen even in C due to extensions.
4925 if (Fn->getType() == Context.OverloadTy) {
4926 OverloadExpr::FindResult find = OverloadExpr::find(Fn);
4927
4928 // We aren't supposed to apply this logic for if there's an '&' involved.
4929 if (!find.HasFormOfMemberPointer) {
4930 OverloadExpr *ovl = find.Expression;
4931 if (isa<UnresolvedLookupExpr>(ovl)) {
4932 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(ovl);
4933 return BuildOverloadedCallExpr(S, Fn, ULE, LParenLoc, ArgExprs,
4934 RParenLoc, ExecConfig);
4935 } else {
4936 return BuildCallToMemberFunction(S, Fn, LParenLoc, ArgExprs,
4937 RParenLoc);
4938 }
4939 }
4940 }
4941
4942 // If we're directly calling a function, get the appropriate declaration.
4943 if (Fn->getType() == Context.UnknownAnyTy) {
4944 ExprResult result = rebuildUnknownAnyFunction(*this, Fn);
4945 if (result.isInvalid()) return ExprError();
4946 Fn = result.get();
4947 }
4948
4949 Expr *NakedFn = Fn->IgnoreParens();
4950
4951 NamedDecl *NDecl = nullptr;
4952 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(NakedFn))
4953 if (UnOp->getOpcode() == UO_AddrOf)
4954 NakedFn = UnOp->getSubExpr()->IgnoreParens();
4955
4956 if (isa<DeclRefExpr>(NakedFn)) {
4957 NDecl = cast<DeclRefExpr>(NakedFn)->getDecl();
4958
4959 FunctionDecl *FDecl = dyn_cast<FunctionDecl>(NDecl);
4960 if (FDecl && FDecl->getBuiltinID()) {
4961 // Rewrite the function decl for this builtin by replacing paramaters
4962 // with no explicit address space with the address space of the arguments
4963 // in ArgExprs.
4964 if ((FDecl = rewriteBuiltinFunctionDecl(this, Context, FDecl, ArgExprs))) {
4965 NDecl = FDecl;
4966 Fn = DeclRefExpr::Create(Context, FDecl->getQualifierLoc(),
4967 SourceLocation(), FDecl, false,
4968 SourceLocation(), FDecl->getType(),
4969 Fn->getValueKind(), FDecl);
4970 }
4971 }
4972 } else if (isa<MemberExpr>(NakedFn))
4973 NDecl = cast<MemberExpr>(NakedFn)->getMemberDecl();
4974
4975 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(NDecl)) {
4976 if (FD->hasAttr<EnableIfAttr>()) {
4977 if (const EnableIfAttr *Attr = CheckEnableIf(FD, ArgExprs, true)) {
4978 Diag(Fn->getLocStart(),
4979 isa<CXXMethodDecl>(FD) ?
4980 diag::err_ovl_no_viable_member_function_in_call :
4981 diag::err_ovl_no_viable_function_in_call)
4982 << FD << FD->getSourceRange();
4983 Diag(FD->getLocation(),
4984 diag::note_ovl_candidate_disabled_by_enable_if_attr)
4985 << Attr->getCond()->getSourceRange() << Attr->getMessage();
4986 }
4987 }
4988 }
4989
4990 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, ArgExprs, RParenLoc,
4991 ExecConfig, IsExecConfig);
4992 }
4993
4994 /// ActOnAsTypeExpr - create a new asType (bitcast) from the arguments.
4995 ///
4996 /// __builtin_astype( value, dst type )
4997 ///
ActOnAsTypeExpr(Expr * E,ParsedType ParsedDestTy,SourceLocation BuiltinLoc,SourceLocation RParenLoc)4998 ExprResult Sema::ActOnAsTypeExpr(Expr *E, ParsedType ParsedDestTy,
4999 SourceLocation BuiltinLoc,
5000 SourceLocation RParenLoc) {
5001 ExprValueKind VK = VK_RValue;
5002 ExprObjectKind OK = OK_Ordinary;
5003 QualType DstTy = GetTypeFromParser(ParsedDestTy);
5004 QualType SrcTy = E->getType();
5005 if (Context.getTypeSize(DstTy) != Context.getTypeSize(SrcTy))
5006 return ExprError(Diag(BuiltinLoc,
5007 diag::err_invalid_astype_of_different_size)
5008 << DstTy
5009 << SrcTy
5010 << E->getSourceRange());
5011 return new (Context) AsTypeExpr(E, DstTy, VK, OK, BuiltinLoc, RParenLoc);
5012 }
5013
5014 /// ActOnConvertVectorExpr - create a new convert-vector expression from the
5015 /// provided arguments.
5016 ///
5017 /// __builtin_convertvector( value, dst type )
5018 ///
ActOnConvertVectorExpr(Expr * E,ParsedType ParsedDestTy,SourceLocation BuiltinLoc,SourceLocation RParenLoc)5019 ExprResult Sema::ActOnConvertVectorExpr(Expr *E, ParsedType ParsedDestTy,
5020 SourceLocation BuiltinLoc,
5021 SourceLocation RParenLoc) {
5022 TypeSourceInfo *TInfo;
5023 GetTypeFromParser(ParsedDestTy, &TInfo);
5024 return SemaConvertVectorExpr(E, TInfo, BuiltinLoc, RParenLoc);
5025 }
5026
5027 /// BuildResolvedCallExpr - Build a call to a resolved expression,
5028 /// i.e. an expression not of \p OverloadTy. The expression should
5029 /// unary-convert to an expression of function-pointer or
5030 /// block-pointer type.
5031 ///
5032 /// \param NDecl the declaration being called, if available
5033 ExprResult
BuildResolvedCallExpr(Expr * Fn,NamedDecl * NDecl,SourceLocation LParenLoc,ArrayRef<Expr * > Args,SourceLocation RParenLoc,Expr * Config,bool IsExecConfig)5034 Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl,
5035 SourceLocation LParenLoc,
5036 ArrayRef<Expr *> Args,
5037 SourceLocation RParenLoc,
5038 Expr *Config, bool IsExecConfig) {
5039 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl);
5040 unsigned BuiltinID = (FDecl ? FDecl->getBuiltinID() : 0);
5041
5042 // Promote the function operand.
5043 // We special-case function promotion here because we only allow promoting
5044 // builtin functions to function pointers in the callee of a call.
5045 ExprResult Result;
5046 if (BuiltinID &&
5047 Fn->getType()->isSpecificBuiltinType(BuiltinType::BuiltinFn)) {
5048 Result = ImpCastExprToType(Fn, Context.getPointerType(FDecl->getType()),
5049 CK_BuiltinFnToFnPtr).get();
5050 } else {
5051 Result = CallExprUnaryConversions(Fn);
5052 }
5053 if (Result.isInvalid())
5054 return ExprError();
5055 Fn = Result.get();
5056
5057 // Make the call expr early, before semantic checks. This guarantees cleanup
5058 // of arguments and function on error.
5059 CallExpr *TheCall;
5060 if (Config)
5061 TheCall = new (Context) CUDAKernelCallExpr(Context, Fn,
5062 cast<CallExpr>(Config), Args,
5063 Context.BoolTy, VK_RValue,
5064 RParenLoc);
5065 else
5066 TheCall = new (Context) CallExpr(Context, Fn, Args, Context.BoolTy,
5067 VK_RValue, RParenLoc);
5068
5069 if (!getLangOpts().CPlusPlus) {
5070 // C cannot always handle TypoExpr nodes in builtin calls and direct
5071 // function calls as their argument checking don't necessarily handle
5072 // dependent types properly, so make sure any TypoExprs have been
5073 // dealt with.
5074 ExprResult Result = CorrectDelayedTyposInExpr(TheCall);
5075 if (!Result.isUsable()) return ExprError();
5076 TheCall = dyn_cast<CallExpr>(Result.get());
5077 if (!TheCall) return Result;
5078 Args = llvm::makeArrayRef(TheCall->getArgs(), TheCall->getNumArgs());
5079 }
5080
5081 // Bail out early if calling a builtin with custom typechecking.
5082 if (BuiltinID && Context.BuiltinInfo.hasCustomTypechecking(BuiltinID))
5083 return CheckBuiltinFunctionCall(FDecl, BuiltinID, TheCall);
5084
5085 retry:
5086 const FunctionType *FuncT;
5087 if (const PointerType *PT = Fn->getType()->getAs<PointerType>()) {
5088 // C99 6.5.2.2p1 - "The expression that denotes the called function shall
5089 // have type pointer to function".
5090 FuncT = PT->getPointeeType()->getAs<FunctionType>();
5091 if (!FuncT)
5092 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function)
5093 << Fn->getType() << Fn->getSourceRange());
5094 } else if (const BlockPointerType *BPT =
5095 Fn->getType()->getAs<BlockPointerType>()) {
5096 FuncT = BPT->getPointeeType()->castAs<FunctionType>();
5097 } else {
5098 // Handle calls to expressions of unknown-any type.
5099 if (Fn->getType() == Context.UnknownAnyTy) {
5100 ExprResult rewrite = rebuildUnknownAnyFunction(*this, Fn);
5101 if (rewrite.isInvalid()) return ExprError();
5102 Fn = rewrite.get();
5103 TheCall->setCallee(Fn);
5104 goto retry;
5105 }
5106
5107 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function)
5108 << Fn->getType() << Fn->getSourceRange());
5109 }
5110
5111 if (getLangOpts().CUDA) {
5112 if (Config) {
5113 // CUDA: Kernel calls must be to global functions
5114 if (FDecl && !FDecl->hasAttr<CUDAGlobalAttr>())
5115 return ExprError(Diag(LParenLoc,diag::err_kern_call_not_global_function)
5116 << FDecl->getName() << Fn->getSourceRange());
5117
5118 // CUDA: Kernel function must have 'void' return type
5119 if (!FuncT->getReturnType()->isVoidType())
5120 return ExprError(Diag(LParenLoc, diag::err_kern_type_not_void_return)
5121 << Fn->getType() << Fn->getSourceRange());
5122 } else {
5123 // CUDA: Calls to global functions must be configured
5124 if (FDecl && FDecl->hasAttr<CUDAGlobalAttr>())
5125 return ExprError(Diag(LParenLoc, diag::err_global_call_not_config)
5126 << FDecl->getName() << Fn->getSourceRange());
5127 }
5128 }
5129
5130 // Check for a valid return type
5131 if (CheckCallReturnType(FuncT->getReturnType(), Fn->getLocStart(), TheCall,
5132 FDecl))
5133 return ExprError();
5134
5135 // We know the result type of the call, set it.
5136 TheCall->setType(FuncT->getCallResultType(Context));
5137 TheCall->setValueKind(Expr::getValueKindForType(FuncT->getReturnType()));
5138
5139 const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT);
5140 if (Proto) {
5141 if (ConvertArgumentsForCall(TheCall, Fn, FDecl, Proto, Args, RParenLoc,
5142 IsExecConfig))
5143 return ExprError();
5144 } else {
5145 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!");
5146
5147 if (FDecl) {
5148 // Check if we have too few/too many template arguments, based
5149 // on our knowledge of the function definition.
5150 const FunctionDecl *Def = nullptr;
5151 if (FDecl->hasBody(Def) && Args.size() != Def->param_size()) {
5152 Proto = Def->getType()->getAs<FunctionProtoType>();
5153 if (!Proto || !(Proto->isVariadic() && Args.size() >= Def->param_size()))
5154 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments)
5155 << (Args.size() > Def->param_size()) << FDecl << Fn->getSourceRange();
5156 }
5157
5158 // If the function we're calling isn't a function prototype, but we have
5159 // a function prototype from a prior declaratiom, use that prototype.
5160 if (!FDecl->hasPrototype())
5161 Proto = FDecl->getType()->getAs<FunctionProtoType>();
5162 }
5163
5164 // Promote the arguments (C99 6.5.2.2p6).
5165 for (unsigned i = 0, e = Args.size(); i != e; i++) {
5166 Expr *Arg = Args[i];
5167
5168 if (Proto && i < Proto->getNumParams()) {
5169 InitializedEntity Entity = InitializedEntity::InitializeParameter(
5170 Context, Proto->getParamType(i), Proto->isParamConsumed(i));
5171 ExprResult ArgE =
5172 PerformCopyInitialization(Entity, SourceLocation(), Arg);
5173 if (ArgE.isInvalid())
5174 return true;
5175
5176 Arg = ArgE.getAs<Expr>();
5177
5178 } else {
5179 ExprResult ArgE = DefaultArgumentPromotion(Arg);
5180
5181 if (ArgE.isInvalid())
5182 return true;
5183
5184 Arg = ArgE.getAs<Expr>();
5185 }
5186
5187 if (RequireCompleteType(Arg->getLocStart(),
5188 Arg->getType(),
5189 diag::err_call_incomplete_argument, Arg))
5190 return ExprError();
5191
5192 TheCall->setArg(i, Arg);
5193 }
5194 }
5195
5196 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl))
5197 if (!Method->isStatic())
5198 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object)
5199 << Fn->getSourceRange());
5200
5201 // Check for sentinels
5202 if (NDecl)
5203 DiagnoseSentinelCalls(NDecl, LParenLoc, Args);
5204
5205 // Do special checking on direct calls to functions.
5206 if (FDecl) {
5207 if (CheckFunctionCall(FDecl, TheCall, Proto))
5208 return ExprError();
5209
5210 if (BuiltinID)
5211 return CheckBuiltinFunctionCall(FDecl, BuiltinID, TheCall);
5212 } else if (NDecl) {
5213 if (CheckPointerCall(NDecl, TheCall, Proto))
5214 return ExprError();
5215 } else {
5216 if (CheckOtherCall(TheCall, Proto))
5217 return ExprError();
5218 }
5219
5220 return MaybeBindToTemporary(TheCall);
5221 }
5222
5223 ExprResult
ActOnCompoundLiteral(SourceLocation LParenLoc,ParsedType Ty,SourceLocation RParenLoc,Expr * InitExpr)5224 Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, ParsedType Ty,
5225 SourceLocation RParenLoc, Expr *InitExpr) {
5226 assert(Ty && "ActOnCompoundLiteral(): missing type");
5227 assert(InitExpr && "ActOnCompoundLiteral(): missing expression");
5228
5229 TypeSourceInfo *TInfo;
5230 QualType literalType = GetTypeFromParser(Ty, &TInfo);
5231 if (!TInfo)
5232 TInfo = Context.getTrivialTypeSourceInfo(literalType);
5233
5234 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, InitExpr);
5235 }
5236
5237 ExprResult
BuildCompoundLiteralExpr(SourceLocation LParenLoc,TypeSourceInfo * TInfo,SourceLocation RParenLoc,Expr * LiteralExpr)5238 Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo,
5239 SourceLocation RParenLoc, Expr *LiteralExpr) {
5240 QualType literalType = TInfo->getType();
5241
5242 if (literalType->isArrayType()) {
5243 if (RequireCompleteType(LParenLoc, Context.getBaseElementType(literalType),
5244 diag::err_illegal_decl_array_incomplete_type,
5245 SourceRange(LParenLoc,
5246 LiteralExpr->getSourceRange().getEnd())))
5247 return ExprError();
5248 if (literalType->isVariableArrayType())
5249 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init)
5250 << SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd()));
5251 } else if (!literalType->isDependentType() &&
5252 RequireCompleteType(LParenLoc, literalType,
5253 diag::err_typecheck_decl_incomplete_type,
5254 SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd())))
5255 return ExprError();
5256
5257 InitializedEntity Entity
5258 = InitializedEntity::InitializeCompoundLiteralInit(TInfo);
5259 InitializationKind Kind
5260 = InitializationKind::CreateCStyleCast(LParenLoc,
5261 SourceRange(LParenLoc, RParenLoc),
5262 /*InitList=*/true);
5263 InitializationSequence InitSeq(*this, Entity, Kind, LiteralExpr);
5264 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, LiteralExpr,
5265 &literalType);
5266 if (Result.isInvalid())
5267 return ExprError();
5268 LiteralExpr = Result.get();
5269
5270 bool isFileScope = getCurFunctionOrMethodDecl() == nullptr;
5271 if (isFileScope &&
5272 !LiteralExpr->isTypeDependent() &&
5273 !LiteralExpr->isValueDependent() &&
5274 !literalType->isDependentType()) { // 6.5.2.5p3
5275 if (CheckForConstantInitializer(LiteralExpr, literalType))
5276 return ExprError();
5277 }
5278
5279 // In C, compound literals are l-values for some reason.
5280 ExprValueKind VK = getLangOpts().CPlusPlus ? VK_RValue : VK_LValue;
5281
5282 return MaybeBindToTemporary(
5283 new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType,
5284 VK, LiteralExpr, isFileScope));
5285 }
5286
5287 ExprResult
ActOnInitList(SourceLocation LBraceLoc,MultiExprArg InitArgList,SourceLocation RBraceLoc)5288 Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg InitArgList,
5289 SourceLocation RBraceLoc) {
5290 // Immediately handle non-overload placeholders. Overloads can be
5291 // resolved contextually, but everything else here can't.
5292 for (unsigned I = 0, E = InitArgList.size(); I != E; ++I) {
5293 if (InitArgList[I]->getType()->isNonOverloadPlaceholderType()) {
5294 ExprResult result = CheckPlaceholderExpr(InitArgList[I]);
5295
5296 // Ignore failures; dropping the entire initializer list because
5297 // of one failure would be terrible for indexing/etc.
5298 if (result.isInvalid()) continue;
5299
5300 InitArgList[I] = result.get();
5301 }
5302 }
5303
5304 // Semantic analysis for initializers is done by ActOnDeclarator() and
5305 // CheckInitializer() - it requires knowledge of the object being intialized.
5306
5307 InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitArgList,
5308 RBraceLoc);
5309 E->setType(Context.VoidTy); // FIXME: just a place holder for now.
5310 return E;
5311 }
5312
5313 /// Do an explicit extend of the given block pointer if we're in ARC.
maybeExtendBlockObject(ExprResult & E)5314 void Sema::maybeExtendBlockObject(ExprResult &E) {
5315 assert(E.get()->getType()->isBlockPointerType());
5316 assert(E.get()->isRValue());
5317
5318 // Only do this in an r-value context.
5319 if (!getLangOpts().ObjCAutoRefCount) return;
5320
5321 E = ImplicitCastExpr::Create(Context, E.get()->getType(),
5322 CK_ARCExtendBlockObject, E.get(),
5323 /*base path*/ nullptr, VK_RValue);
5324 ExprNeedsCleanups = true;
5325 }
5326
5327 /// Prepare a conversion of the given expression to an ObjC object
5328 /// pointer type.
PrepareCastToObjCObjectPointer(ExprResult & E)5329 CastKind Sema::PrepareCastToObjCObjectPointer(ExprResult &E) {
5330 QualType type = E.get()->getType();
5331 if (type->isObjCObjectPointerType()) {
5332 return CK_BitCast;
5333 } else if (type->isBlockPointerType()) {
5334 maybeExtendBlockObject(E);
5335 return CK_BlockPointerToObjCPointerCast;
5336 } else {
5337 assert(type->isPointerType());
5338 return CK_CPointerToObjCPointerCast;
5339 }
5340 }
5341
5342 /// Prepares for a scalar cast, performing all the necessary stages
5343 /// except the final cast and returning the kind required.
PrepareScalarCast(ExprResult & Src,QualType DestTy)5344 CastKind Sema::PrepareScalarCast(ExprResult &Src, QualType DestTy) {
5345 // Both Src and Dest are scalar types, i.e. arithmetic or pointer.
5346 // Also, callers should have filtered out the invalid cases with
5347 // pointers. Everything else should be possible.
5348
5349 QualType SrcTy = Src.get()->getType();
5350 if (Context.hasSameUnqualifiedType(SrcTy, DestTy))
5351 return CK_NoOp;
5352
5353 switch (Type::ScalarTypeKind SrcKind = SrcTy->getScalarTypeKind()) {
5354 case Type::STK_MemberPointer:
5355 llvm_unreachable("member pointer type in C");
5356
5357 case Type::STK_CPointer:
5358 case Type::STK_BlockPointer:
5359 case Type::STK_ObjCObjectPointer:
5360 switch (DestTy->getScalarTypeKind()) {
5361 case Type::STK_CPointer: {
5362 unsigned SrcAS = SrcTy->getPointeeType().getAddressSpace();
5363 unsigned DestAS = DestTy->getPointeeType().getAddressSpace();
5364 if (SrcAS != DestAS)
5365 return CK_AddressSpaceConversion;
5366 return CK_BitCast;
5367 }
5368 case Type::STK_BlockPointer:
5369 return (SrcKind == Type::STK_BlockPointer
5370 ? CK_BitCast : CK_AnyPointerToBlockPointerCast);
5371 case Type::STK_ObjCObjectPointer:
5372 if (SrcKind == Type::STK_ObjCObjectPointer)
5373 return CK_BitCast;
5374 if (SrcKind == Type::STK_CPointer)
5375 return CK_CPointerToObjCPointerCast;
5376 maybeExtendBlockObject(Src);
5377 return CK_BlockPointerToObjCPointerCast;
5378 case Type::STK_Bool:
5379 return CK_PointerToBoolean;
5380 case Type::STK_Integral:
5381 return CK_PointerToIntegral;
5382 case Type::STK_Floating:
5383 case Type::STK_FloatingComplex:
5384 case Type::STK_IntegralComplex:
5385 case Type::STK_MemberPointer:
5386 llvm_unreachable("illegal cast from pointer");
5387 }
5388 llvm_unreachable("Should have returned before this");
5389
5390 case Type::STK_Bool: // casting from bool is like casting from an integer
5391 case Type::STK_Integral:
5392 switch (DestTy->getScalarTypeKind()) {
5393 case Type::STK_CPointer:
5394 case Type::STK_ObjCObjectPointer:
5395 case Type::STK_BlockPointer:
5396 if (Src.get()->isNullPointerConstant(Context,
5397 Expr::NPC_ValueDependentIsNull))
5398 return CK_NullToPointer;
5399 return CK_IntegralToPointer;
5400 case Type::STK_Bool:
5401 return CK_IntegralToBoolean;
5402 case Type::STK_Integral:
5403 return CK_IntegralCast;
5404 case Type::STK_Floating:
5405 return CK_IntegralToFloating;
5406 case Type::STK_IntegralComplex:
5407 Src = ImpCastExprToType(Src.get(),
5408 DestTy->castAs<ComplexType>()->getElementType(),
5409 CK_IntegralCast);
5410 return CK_IntegralRealToComplex;
5411 case Type::STK_FloatingComplex:
5412 Src = ImpCastExprToType(Src.get(),
5413 DestTy->castAs<ComplexType>()->getElementType(),
5414 CK_IntegralToFloating);
5415 return CK_FloatingRealToComplex;
5416 case Type::STK_MemberPointer:
5417 llvm_unreachable("member pointer type in C");
5418 }
5419 llvm_unreachable("Should have returned before this");
5420
5421 case Type::STK_Floating:
5422 switch (DestTy->getScalarTypeKind()) {
5423 case Type::STK_Floating:
5424 return CK_FloatingCast;
5425 case Type::STK_Bool:
5426 return CK_FloatingToBoolean;
5427 case Type::STK_Integral:
5428 return CK_FloatingToIntegral;
5429 case Type::STK_FloatingComplex:
5430 Src = ImpCastExprToType(Src.get(),
5431 DestTy->castAs<ComplexType>()->getElementType(),
5432 CK_FloatingCast);
5433 return CK_FloatingRealToComplex;
5434 case Type::STK_IntegralComplex:
5435 Src = ImpCastExprToType(Src.get(),
5436 DestTy->castAs<ComplexType>()->getElementType(),
5437 CK_FloatingToIntegral);
5438 return CK_IntegralRealToComplex;
5439 case Type::STK_CPointer:
5440 case Type::STK_ObjCObjectPointer:
5441 case Type::STK_BlockPointer:
5442 llvm_unreachable("valid float->pointer cast?");
5443 case Type::STK_MemberPointer:
5444 llvm_unreachable("member pointer type in C");
5445 }
5446 llvm_unreachable("Should have returned before this");
5447
5448 case Type::STK_FloatingComplex:
5449 switch (DestTy->getScalarTypeKind()) {
5450 case Type::STK_FloatingComplex:
5451 return CK_FloatingComplexCast;
5452 case Type::STK_IntegralComplex:
5453 return CK_FloatingComplexToIntegralComplex;
5454 case Type::STK_Floating: {
5455 QualType ET = SrcTy->castAs<ComplexType>()->getElementType();
5456 if (Context.hasSameType(ET, DestTy))
5457 return CK_FloatingComplexToReal;
5458 Src = ImpCastExprToType(Src.get(), ET, CK_FloatingComplexToReal);
5459 return CK_FloatingCast;
5460 }
5461 case Type::STK_Bool:
5462 return CK_FloatingComplexToBoolean;
5463 case Type::STK_Integral:
5464 Src = ImpCastExprToType(Src.get(),
5465 SrcTy->castAs<ComplexType>()->getElementType(),
5466 CK_FloatingComplexToReal);
5467 return CK_FloatingToIntegral;
5468 case Type::STK_CPointer:
5469 case Type::STK_ObjCObjectPointer:
5470 case Type::STK_BlockPointer:
5471 llvm_unreachable("valid complex float->pointer cast?");
5472 case Type::STK_MemberPointer:
5473 llvm_unreachable("member pointer type in C");
5474 }
5475 llvm_unreachable("Should have returned before this");
5476
5477 case Type::STK_IntegralComplex:
5478 switch (DestTy->getScalarTypeKind()) {
5479 case Type::STK_FloatingComplex:
5480 return CK_IntegralComplexToFloatingComplex;
5481 case Type::STK_IntegralComplex:
5482 return CK_IntegralComplexCast;
5483 case Type::STK_Integral: {
5484 QualType ET = SrcTy->castAs<ComplexType>()->getElementType();
5485 if (Context.hasSameType(ET, DestTy))
5486 return CK_IntegralComplexToReal;
5487 Src = ImpCastExprToType(Src.get(), ET, CK_IntegralComplexToReal);
5488 return CK_IntegralCast;
5489 }
5490 case Type::STK_Bool:
5491 return CK_IntegralComplexToBoolean;
5492 case Type::STK_Floating:
5493 Src = ImpCastExprToType(Src.get(),
5494 SrcTy->castAs<ComplexType>()->getElementType(),
5495 CK_IntegralComplexToReal);
5496 return CK_IntegralToFloating;
5497 case Type::STK_CPointer:
5498 case Type::STK_ObjCObjectPointer:
5499 case Type::STK_BlockPointer:
5500 llvm_unreachable("valid complex int->pointer cast?");
5501 case Type::STK_MemberPointer:
5502 llvm_unreachable("member pointer type in C");
5503 }
5504 llvm_unreachable("Should have returned before this");
5505 }
5506
5507 llvm_unreachable("Unhandled scalar cast");
5508 }
5509
breakDownVectorType(QualType type,uint64_t & len,QualType & eltType)5510 static bool breakDownVectorType(QualType type, uint64_t &len,
5511 QualType &eltType) {
5512 // Vectors are simple.
5513 if (const VectorType *vecType = type->getAs<VectorType>()) {
5514 len = vecType->getNumElements();
5515 eltType = vecType->getElementType();
5516 assert(eltType->isScalarType());
5517 return true;
5518 }
5519
5520 // We allow lax conversion to and from non-vector types, but only if
5521 // they're real types (i.e. non-complex, non-pointer scalar types).
5522 if (!type->isRealType()) return false;
5523
5524 len = 1;
5525 eltType = type;
5526 return true;
5527 }
5528
5529 /// Are the two types lax-compatible vector types? That is, given
5530 /// that one of them is a vector, do they have equal storage sizes,
5531 /// where the storage size is the number of elements times the element
5532 /// size?
5533 ///
5534 /// This will also return false if either of the types is neither a
5535 /// vector nor a real type.
areLaxCompatibleVectorTypes(QualType srcTy,QualType destTy)5536 bool Sema::areLaxCompatibleVectorTypes(QualType srcTy, QualType destTy) {
5537 assert(destTy->isVectorType() || srcTy->isVectorType());
5538
5539 // Disallow lax conversions between scalars and ExtVectors (these
5540 // conversions are allowed for other vector types because common headers
5541 // depend on them). Most scalar OP ExtVector cases are handled by the
5542 // splat path anyway, which does what we want (convert, not bitcast).
5543 // What this rules out for ExtVectors is crazy things like char4*float.
5544 if (srcTy->isScalarType() && destTy->isExtVectorType()) return false;
5545 if (destTy->isScalarType() && srcTy->isExtVectorType()) return false;
5546
5547 uint64_t srcLen, destLen;
5548 QualType srcEltTy, destEltTy;
5549 if (!breakDownVectorType(srcTy, srcLen, srcEltTy)) return false;
5550 if (!breakDownVectorType(destTy, destLen, destEltTy)) return false;
5551
5552 // ASTContext::getTypeSize will return the size rounded up to a
5553 // power of 2, so instead of using that, we need to use the raw
5554 // element size multiplied by the element count.
5555 uint64_t srcEltSize = Context.getTypeSize(srcEltTy);
5556 uint64_t destEltSize = Context.getTypeSize(destEltTy);
5557
5558 return (srcLen * srcEltSize == destLen * destEltSize);
5559 }
5560
5561 /// Is this a legal conversion between two types, one of which is
5562 /// known to be a vector type?
isLaxVectorConversion(QualType srcTy,QualType destTy)5563 bool Sema::isLaxVectorConversion(QualType srcTy, QualType destTy) {
5564 assert(destTy->isVectorType() || srcTy->isVectorType());
5565
5566 if (!Context.getLangOpts().LaxVectorConversions)
5567 return false;
5568 return areLaxCompatibleVectorTypes(srcTy, destTy);
5569 }
5570
CheckVectorCast(SourceRange R,QualType VectorTy,QualType Ty,CastKind & Kind)5571 bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty,
5572 CastKind &Kind) {
5573 assert(VectorTy->isVectorType() && "Not a vector type!");
5574
5575 if (Ty->isVectorType() || Ty->isIntegralType(Context)) {
5576 if (!areLaxCompatibleVectorTypes(Ty, VectorTy))
5577 return Diag(R.getBegin(),
5578 Ty->isVectorType() ?
5579 diag::err_invalid_conversion_between_vectors :
5580 diag::err_invalid_conversion_between_vector_and_integer)
5581 << VectorTy << Ty << R;
5582 } else
5583 return Diag(R.getBegin(),
5584 diag::err_invalid_conversion_between_vector_and_scalar)
5585 << VectorTy << Ty << R;
5586
5587 Kind = CK_BitCast;
5588 return false;
5589 }
5590
CheckExtVectorCast(SourceRange R,QualType DestTy,Expr * CastExpr,CastKind & Kind)5591 ExprResult Sema::CheckExtVectorCast(SourceRange R, QualType DestTy,
5592 Expr *CastExpr, CastKind &Kind) {
5593 assert(DestTy->isExtVectorType() && "Not an extended vector type!");
5594
5595 QualType SrcTy = CastExpr->getType();
5596
5597 // If SrcTy is a VectorType, the total size must match to explicitly cast to
5598 // an ExtVectorType.
5599 // In OpenCL, casts between vectors of different types are not allowed.
5600 // (See OpenCL 6.2).
5601 if (SrcTy->isVectorType()) {
5602 if (!areLaxCompatibleVectorTypes(SrcTy, DestTy)
5603 || (getLangOpts().OpenCL &&
5604 (DestTy.getCanonicalType() != SrcTy.getCanonicalType()))) {
5605 Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors)
5606 << DestTy << SrcTy << R;
5607 return ExprError();
5608 }
5609 Kind = CK_BitCast;
5610 return CastExpr;
5611 }
5612
5613 // All non-pointer scalars can be cast to ExtVector type. The appropriate
5614 // conversion will take place first from scalar to elt type, and then
5615 // splat from elt type to vector.
5616 if (SrcTy->isPointerType())
5617 return Diag(R.getBegin(),
5618 diag::err_invalid_conversion_between_vector_and_scalar)
5619 << DestTy << SrcTy << R;
5620
5621 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType();
5622 ExprResult CastExprRes = CastExpr;
5623 CastKind CK = PrepareScalarCast(CastExprRes, DestElemTy);
5624 if (CastExprRes.isInvalid())
5625 return ExprError();
5626 CastExpr = ImpCastExprToType(CastExprRes.get(), DestElemTy, CK).get();
5627
5628 Kind = CK_VectorSplat;
5629 return CastExpr;
5630 }
5631
5632 ExprResult
ActOnCastExpr(Scope * S,SourceLocation LParenLoc,Declarator & D,ParsedType & Ty,SourceLocation RParenLoc,Expr * CastExpr)5633 Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc,
5634 Declarator &D, ParsedType &Ty,
5635 SourceLocation RParenLoc, Expr *CastExpr) {
5636 assert(!D.isInvalidType() && (CastExpr != nullptr) &&
5637 "ActOnCastExpr(): missing type or expr");
5638
5639 TypeSourceInfo *castTInfo = GetTypeForDeclaratorCast(D, CastExpr->getType());
5640 if (D.isInvalidType())
5641 return ExprError();
5642
5643 if (getLangOpts().CPlusPlus) {
5644 // Check that there are no default arguments (C++ only).
5645 CheckExtraCXXDefaultArguments(D);
5646 } else {
5647 // Make sure any TypoExprs have been dealt with.
5648 ExprResult Res = CorrectDelayedTyposInExpr(CastExpr);
5649 if (!Res.isUsable())
5650 return ExprError();
5651 CastExpr = Res.get();
5652 }
5653
5654 checkUnusedDeclAttributes(D);
5655
5656 QualType castType = castTInfo->getType();
5657 Ty = CreateParsedType(castType, castTInfo);
5658
5659 bool isVectorLiteral = false;
5660
5661 // Check for an altivec or OpenCL literal,
5662 // i.e. all the elements are integer constants.
5663 ParenExpr *PE = dyn_cast<ParenExpr>(CastExpr);
5664 ParenListExpr *PLE = dyn_cast<ParenListExpr>(CastExpr);
5665 if ((getLangOpts().AltiVec || getLangOpts().ZVector || getLangOpts().OpenCL)
5666 && castType->isVectorType() && (PE || PLE)) {
5667 if (PLE && PLE->getNumExprs() == 0) {
5668 Diag(PLE->getExprLoc(), diag::err_altivec_empty_initializer);
5669 return ExprError();
5670 }
5671 if (PE || PLE->getNumExprs() == 1) {
5672 Expr *E = (PE ? PE->getSubExpr() : PLE->getExpr(0));
5673 if (!E->getType()->isVectorType())
5674 isVectorLiteral = true;
5675 }
5676 else
5677 isVectorLiteral = true;
5678 }
5679
5680 // If this is a vector initializer, '(' type ')' '(' init, ..., init ')'
5681 // then handle it as such.
5682 if (isVectorLiteral)
5683 return BuildVectorLiteral(LParenLoc, RParenLoc, CastExpr, castTInfo);
5684
5685 // If the Expr being casted is a ParenListExpr, handle it specially.
5686 // This is not an AltiVec-style cast, so turn the ParenListExpr into a
5687 // sequence of BinOp comma operators.
5688 if (isa<ParenListExpr>(CastExpr)) {
5689 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, CastExpr);
5690 if (Result.isInvalid()) return ExprError();
5691 CastExpr = Result.get();
5692 }
5693
5694 if (getLangOpts().CPlusPlus && !castType->isVoidType() &&
5695 !getSourceManager().isInSystemMacro(LParenLoc))
5696 Diag(LParenLoc, diag::warn_old_style_cast) << CastExpr->getSourceRange();
5697
5698 CheckTollFreeBridgeCast(castType, CastExpr);
5699
5700 CheckObjCBridgeRelatedCast(castType, CastExpr);
5701
5702 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, CastExpr);
5703 }
5704
BuildVectorLiteral(SourceLocation LParenLoc,SourceLocation RParenLoc,Expr * E,TypeSourceInfo * TInfo)5705 ExprResult Sema::BuildVectorLiteral(SourceLocation LParenLoc,
5706 SourceLocation RParenLoc, Expr *E,
5707 TypeSourceInfo *TInfo) {
5708 assert((isa<ParenListExpr>(E) || isa<ParenExpr>(E)) &&
5709 "Expected paren or paren list expression");
5710
5711 Expr **exprs;
5712 unsigned numExprs;
5713 Expr *subExpr;
5714 SourceLocation LiteralLParenLoc, LiteralRParenLoc;
5715 if (ParenListExpr *PE = dyn_cast<ParenListExpr>(E)) {
5716 LiteralLParenLoc = PE->getLParenLoc();
5717 LiteralRParenLoc = PE->getRParenLoc();
5718 exprs = PE->getExprs();
5719 numExprs = PE->getNumExprs();
5720 } else { // isa<ParenExpr> by assertion at function entrance
5721 LiteralLParenLoc = cast<ParenExpr>(E)->getLParen();
5722 LiteralRParenLoc = cast<ParenExpr>(E)->getRParen();
5723 subExpr = cast<ParenExpr>(E)->getSubExpr();
5724 exprs = &subExpr;
5725 numExprs = 1;
5726 }
5727
5728 QualType Ty = TInfo->getType();
5729 assert(Ty->isVectorType() && "Expected vector type");
5730
5731 SmallVector<Expr *, 8> initExprs;
5732 const VectorType *VTy = Ty->getAs<VectorType>();
5733 unsigned numElems = Ty->getAs<VectorType>()->getNumElements();
5734
5735 // '(...)' form of vector initialization in AltiVec: the number of
5736 // initializers must be one or must match the size of the vector.
5737 // If a single value is specified in the initializer then it will be
5738 // replicated to all the components of the vector
5739 if (VTy->getVectorKind() == VectorType::AltiVecVector) {
5740 // The number of initializers must be one or must match the size of the
5741 // vector. If a single value is specified in the initializer then it will
5742 // be replicated to all the components of the vector
5743 if (numExprs == 1) {
5744 QualType ElemTy = Ty->getAs<VectorType>()->getElementType();
5745 ExprResult Literal = DefaultLvalueConversion(exprs[0]);
5746 if (Literal.isInvalid())
5747 return ExprError();
5748 Literal = ImpCastExprToType(Literal.get(), ElemTy,
5749 PrepareScalarCast(Literal, ElemTy));
5750 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Literal.get());
5751 }
5752 else if (numExprs < numElems) {
5753 Diag(E->getExprLoc(),
5754 diag::err_incorrect_number_of_vector_initializers);
5755 return ExprError();
5756 }
5757 else
5758 initExprs.append(exprs, exprs + numExprs);
5759 }
5760 else {
5761 // For OpenCL, when the number of initializers is a single value,
5762 // it will be replicated to all components of the vector.
5763 if (getLangOpts().OpenCL &&
5764 VTy->getVectorKind() == VectorType::GenericVector &&
5765 numExprs == 1) {
5766 QualType ElemTy = Ty->getAs<VectorType>()->getElementType();
5767 ExprResult Literal = DefaultLvalueConversion(exprs[0]);
5768 if (Literal.isInvalid())
5769 return ExprError();
5770 Literal = ImpCastExprToType(Literal.get(), ElemTy,
5771 PrepareScalarCast(Literal, ElemTy));
5772 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Literal.get());
5773 }
5774
5775 initExprs.append(exprs, exprs + numExprs);
5776 }
5777 // FIXME: This means that pretty-printing the final AST will produce curly
5778 // braces instead of the original commas.
5779 InitListExpr *initE = new (Context) InitListExpr(Context, LiteralLParenLoc,
5780 initExprs, LiteralRParenLoc);
5781 initE->setType(Ty);
5782 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, initE);
5783 }
5784
5785 /// This is not an AltiVec-style cast or or C++ direct-initialization, so turn
5786 /// the ParenListExpr into a sequence of comma binary operators.
5787 ExprResult
MaybeConvertParenListExprToParenExpr(Scope * S,Expr * OrigExpr)5788 Sema::MaybeConvertParenListExprToParenExpr(Scope *S, Expr *OrigExpr) {
5789 ParenListExpr *E = dyn_cast<ParenListExpr>(OrigExpr);
5790 if (!E)
5791 return OrigExpr;
5792
5793 ExprResult Result(E->getExpr(0));
5794
5795 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i)
5796 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, Result.get(),
5797 E->getExpr(i));
5798
5799 if (Result.isInvalid()) return ExprError();
5800
5801 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), Result.get());
5802 }
5803
ActOnParenListExpr(SourceLocation L,SourceLocation R,MultiExprArg Val)5804 ExprResult Sema::ActOnParenListExpr(SourceLocation L,
5805 SourceLocation R,
5806 MultiExprArg Val) {
5807 Expr *expr = new (Context) ParenListExpr(Context, L, Val, R);
5808 return expr;
5809 }
5810
5811 /// \brief Emit a specialized diagnostic when one expression is a null pointer
5812 /// constant and the other is not a pointer. Returns true if a diagnostic is
5813 /// emitted.
DiagnoseConditionalForNull(Expr * LHSExpr,Expr * RHSExpr,SourceLocation QuestionLoc)5814 bool Sema::DiagnoseConditionalForNull(Expr *LHSExpr, Expr *RHSExpr,
5815 SourceLocation QuestionLoc) {
5816 Expr *NullExpr = LHSExpr;
5817 Expr *NonPointerExpr = RHSExpr;
5818 Expr::NullPointerConstantKind NullKind =
5819 NullExpr->isNullPointerConstant(Context,
5820 Expr::NPC_ValueDependentIsNotNull);
5821
5822 if (NullKind == Expr::NPCK_NotNull) {
5823 NullExpr = RHSExpr;
5824 NonPointerExpr = LHSExpr;
5825 NullKind =
5826 NullExpr->isNullPointerConstant(Context,
5827 Expr::NPC_ValueDependentIsNotNull);
5828 }
5829
5830 if (NullKind == Expr::NPCK_NotNull)
5831 return false;
5832
5833 if (NullKind == Expr::NPCK_ZeroExpression)
5834 return false;
5835
5836 if (NullKind == Expr::NPCK_ZeroLiteral) {
5837 // In this case, check to make sure that we got here from a "NULL"
5838 // string in the source code.
5839 NullExpr = NullExpr->IgnoreParenImpCasts();
5840 SourceLocation loc = NullExpr->getExprLoc();
5841 if (!findMacroSpelling(loc, "NULL"))
5842 return false;
5843 }
5844
5845 int DiagType = (NullKind == Expr::NPCK_CXX11_nullptr);
5846 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands_null)
5847 << NonPointerExpr->getType() << DiagType
5848 << NonPointerExpr->getSourceRange();
5849 return true;
5850 }
5851
5852 /// \brief Return false if the condition expression is valid, true otherwise.
checkCondition(Sema & S,Expr * Cond,SourceLocation QuestionLoc)5853 static bool checkCondition(Sema &S, Expr *Cond, SourceLocation QuestionLoc) {
5854 QualType CondTy = Cond->getType();
5855
5856 // OpenCL v1.1 s6.3.i says the condition cannot be a floating point type.
5857 if (S.getLangOpts().OpenCL && CondTy->isFloatingType()) {
5858 S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_nonfloat)
5859 << CondTy << Cond->getSourceRange();
5860 return true;
5861 }
5862
5863 // C99 6.5.15p2
5864 if (CondTy->isScalarType()) return false;
5865
5866 S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_scalar)
5867 << CondTy << Cond->getSourceRange();
5868 return true;
5869 }
5870
5871 /// \brief Handle when one or both operands are void type.
checkConditionalVoidType(Sema & S,ExprResult & LHS,ExprResult & RHS)5872 static QualType checkConditionalVoidType(Sema &S, ExprResult &LHS,
5873 ExprResult &RHS) {
5874 Expr *LHSExpr = LHS.get();
5875 Expr *RHSExpr = RHS.get();
5876
5877 if (!LHSExpr->getType()->isVoidType())
5878 S.Diag(RHSExpr->getLocStart(), diag::ext_typecheck_cond_one_void)
5879 << RHSExpr->getSourceRange();
5880 if (!RHSExpr->getType()->isVoidType())
5881 S.Diag(LHSExpr->getLocStart(), diag::ext_typecheck_cond_one_void)
5882 << LHSExpr->getSourceRange();
5883 LHS = S.ImpCastExprToType(LHS.get(), S.Context.VoidTy, CK_ToVoid);
5884 RHS = S.ImpCastExprToType(RHS.get(), S.Context.VoidTy, CK_ToVoid);
5885 return S.Context.VoidTy;
5886 }
5887
5888 /// \brief Return false if the NullExpr can be promoted to PointerTy,
5889 /// true otherwise.
checkConditionalNullPointer(Sema & S,ExprResult & NullExpr,QualType PointerTy)5890 static bool checkConditionalNullPointer(Sema &S, ExprResult &NullExpr,
5891 QualType PointerTy) {
5892 if ((!PointerTy->isAnyPointerType() && !PointerTy->isBlockPointerType()) ||
5893 !NullExpr.get()->isNullPointerConstant(S.Context,
5894 Expr::NPC_ValueDependentIsNull))
5895 return true;
5896
5897 NullExpr = S.ImpCastExprToType(NullExpr.get(), PointerTy, CK_NullToPointer);
5898 return false;
5899 }
5900
5901 /// \brief Checks compatibility between two pointers and return the resulting
5902 /// type.
checkConditionalPointerCompatibility(Sema & S,ExprResult & LHS,ExprResult & RHS,SourceLocation Loc)5903 static QualType checkConditionalPointerCompatibility(Sema &S, ExprResult &LHS,
5904 ExprResult &RHS,
5905 SourceLocation Loc) {
5906 QualType LHSTy = LHS.get()->getType();
5907 QualType RHSTy = RHS.get()->getType();
5908
5909 if (S.Context.hasSameType(LHSTy, RHSTy)) {
5910 // Two identical pointers types are always compatible.
5911 return LHSTy;
5912 }
5913
5914 QualType lhptee, rhptee;
5915
5916 // Get the pointee types.
5917 bool IsBlockPointer = false;
5918 if (const BlockPointerType *LHSBTy = LHSTy->getAs<BlockPointerType>()) {
5919 lhptee = LHSBTy->getPointeeType();
5920 rhptee = RHSTy->castAs<BlockPointerType>()->getPointeeType();
5921 IsBlockPointer = true;
5922 } else {
5923 lhptee = LHSTy->castAs<PointerType>()->getPointeeType();
5924 rhptee = RHSTy->castAs<PointerType>()->getPointeeType();
5925 }
5926
5927 // C99 6.5.15p6: If both operands are pointers to compatible types or to
5928 // differently qualified versions of compatible types, the result type is
5929 // a pointer to an appropriately qualified version of the composite
5930 // type.
5931
5932 // Only CVR-qualifiers exist in the standard, and the differently-qualified
5933 // clause doesn't make sense for our extensions. E.g. address space 2 should
5934 // be incompatible with address space 3: they may live on different devices or
5935 // anything.
5936 Qualifiers lhQual = lhptee.getQualifiers();
5937 Qualifiers rhQual = rhptee.getQualifiers();
5938
5939 unsigned MergedCVRQual = lhQual.getCVRQualifiers() | rhQual.getCVRQualifiers();
5940 lhQual.removeCVRQualifiers();
5941 rhQual.removeCVRQualifiers();
5942
5943 lhptee = S.Context.getQualifiedType(lhptee.getUnqualifiedType(), lhQual);
5944 rhptee = S.Context.getQualifiedType(rhptee.getUnqualifiedType(), rhQual);
5945
5946 QualType CompositeTy = S.Context.mergeTypes(lhptee, rhptee);
5947
5948 if (CompositeTy.isNull()) {
5949 S.Diag(Loc, diag::ext_typecheck_cond_incompatible_pointers)
5950 << LHSTy << RHSTy << LHS.get()->getSourceRange()
5951 << RHS.get()->getSourceRange();
5952 // In this situation, we assume void* type. No especially good
5953 // reason, but this is what gcc does, and we do have to pick
5954 // to get a consistent AST.
5955 QualType incompatTy = S.Context.getPointerType(S.Context.VoidTy);
5956 LHS = S.ImpCastExprToType(LHS.get(), incompatTy, CK_BitCast);
5957 RHS = S.ImpCastExprToType(RHS.get(), incompatTy, CK_BitCast);
5958 return incompatTy;
5959 }
5960
5961 // The pointer types are compatible.
5962 QualType ResultTy = CompositeTy.withCVRQualifiers(MergedCVRQual);
5963 if (IsBlockPointer)
5964 ResultTy = S.Context.getBlockPointerType(ResultTy);
5965 else
5966 ResultTy = S.Context.getPointerType(ResultTy);
5967
5968 LHS = S.ImpCastExprToType(LHS.get(), ResultTy, CK_BitCast);
5969 RHS = S.ImpCastExprToType(RHS.get(), ResultTy, CK_BitCast);
5970 return ResultTy;
5971 }
5972
5973 /// \brief Return the resulting type when the operands are both block pointers.
checkConditionalBlockPointerCompatibility(Sema & S,ExprResult & LHS,ExprResult & RHS,SourceLocation Loc)5974 static QualType checkConditionalBlockPointerCompatibility(Sema &S,
5975 ExprResult &LHS,
5976 ExprResult &RHS,
5977 SourceLocation Loc) {
5978 QualType LHSTy = LHS.get()->getType();
5979 QualType RHSTy = RHS.get()->getType();
5980
5981 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) {
5982 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) {
5983 QualType destType = S.Context.getPointerType(S.Context.VoidTy);
5984 LHS = S.ImpCastExprToType(LHS.get(), destType, CK_BitCast);
5985 RHS = S.ImpCastExprToType(RHS.get(), destType, CK_BitCast);
5986 return destType;
5987 }
5988 S.Diag(Loc, diag::err_typecheck_cond_incompatible_operands)
5989 << LHSTy << RHSTy << LHS.get()->getSourceRange()
5990 << RHS.get()->getSourceRange();
5991 return QualType();
5992 }
5993
5994 // We have 2 block pointer types.
5995 return checkConditionalPointerCompatibility(S, LHS, RHS, Loc);
5996 }
5997
5998 /// \brief Return the resulting type when the operands are both pointers.
5999 static QualType
checkConditionalObjectPointersCompatibility(Sema & S,ExprResult & LHS,ExprResult & RHS,SourceLocation Loc)6000 checkConditionalObjectPointersCompatibility(Sema &S, ExprResult &LHS,
6001 ExprResult &RHS,
6002 SourceLocation Loc) {
6003 // get the pointer types
6004 QualType LHSTy = LHS.get()->getType();
6005 QualType RHSTy = RHS.get()->getType();
6006
6007 // get the "pointed to" types
6008 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType();
6009 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType();
6010
6011 // ignore qualifiers on void (C99 6.5.15p3, clause 6)
6012 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) {
6013 // Figure out necessary qualifiers (C99 6.5.15p6)
6014 QualType destPointee
6015 = S.Context.getQualifiedType(lhptee, rhptee.getQualifiers());
6016 QualType destType = S.Context.getPointerType(destPointee);
6017 // Add qualifiers if necessary.
6018 LHS = S.ImpCastExprToType(LHS.get(), destType, CK_NoOp);
6019 // Promote to void*.
6020 RHS = S.ImpCastExprToType(RHS.get(), destType, CK_BitCast);
6021 return destType;
6022 }
6023 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) {
6024 QualType destPointee
6025 = S.Context.getQualifiedType(rhptee, lhptee.getQualifiers());
6026 QualType destType = S.Context.getPointerType(destPointee);
6027 // Add qualifiers if necessary.
6028 RHS = S.ImpCastExprToType(RHS.get(), destType, CK_NoOp);
6029 // Promote to void*.
6030 LHS = S.ImpCastExprToType(LHS.get(), destType, CK_BitCast);
6031 return destType;
6032 }
6033
6034 return checkConditionalPointerCompatibility(S, LHS, RHS, Loc);
6035 }
6036
6037 /// \brief Return false if the first expression is not an integer and the second
6038 /// expression is not a pointer, true otherwise.
checkPointerIntegerMismatch(Sema & S,ExprResult & Int,Expr * PointerExpr,SourceLocation Loc,bool IsIntFirstExpr)6039 static bool checkPointerIntegerMismatch(Sema &S, ExprResult &Int,
6040 Expr* PointerExpr, SourceLocation Loc,
6041 bool IsIntFirstExpr) {
6042 if (!PointerExpr->getType()->isPointerType() ||
6043 !Int.get()->getType()->isIntegerType())
6044 return false;
6045
6046 Expr *Expr1 = IsIntFirstExpr ? Int.get() : PointerExpr;
6047 Expr *Expr2 = IsIntFirstExpr ? PointerExpr : Int.get();
6048
6049 S.Diag(Loc, diag::ext_typecheck_cond_pointer_integer_mismatch)
6050 << Expr1->getType() << Expr2->getType()
6051 << Expr1->getSourceRange() << Expr2->getSourceRange();
6052 Int = S.ImpCastExprToType(Int.get(), PointerExpr->getType(),
6053 CK_IntegralToPointer);
6054 return true;
6055 }
6056
6057 /// \brief Simple conversion between integer and floating point types.
6058 ///
6059 /// Used when handling the OpenCL conditional operator where the
6060 /// condition is a vector while the other operands are scalar.
6061 ///
6062 /// OpenCL v1.1 s6.3.i and s6.11.6 together require that the scalar
6063 /// types are either integer or floating type. Between the two
6064 /// operands, the type with the higher rank is defined as the "result
6065 /// type". The other operand needs to be promoted to the same type. No
6066 /// other type promotion is allowed. We cannot use
6067 /// UsualArithmeticConversions() for this purpose, since it always
6068 /// promotes promotable types.
OpenCLArithmeticConversions(Sema & S,ExprResult & LHS,ExprResult & RHS,SourceLocation QuestionLoc)6069 static QualType OpenCLArithmeticConversions(Sema &S, ExprResult &LHS,
6070 ExprResult &RHS,
6071 SourceLocation QuestionLoc) {
6072 LHS = S.DefaultFunctionArrayLvalueConversion(LHS.get());
6073 if (LHS.isInvalid())
6074 return QualType();
6075 RHS = S.DefaultFunctionArrayLvalueConversion(RHS.get());
6076 if (RHS.isInvalid())
6077 return QualType();
6078
6079 // For conversion purposes, we ignore any qualifiers.
6080 // For example, "const float" and "float" are equivalent.
6081 QualType LHSType =
6082 S.Context.getCanonicalType(LHS.get()->getType()).getUnqualifiedType();
6083 QualType RHSType =
6084 S.Context.getCanonicalType(RHS.get()->getType()).getUnqualifiedType();
6085
6086 if (!LHSType->isIntegerType() && !LHSType->isRealFloatingType()) {
6087 S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_int_float)
6088 << LHSType << LHS.get()->getSourceRange();
6089 return QualType();
6090 }
6091
6092 if (!RHSType->isIntegerType() && !RHSType->isRealFloatingType()) {
6093 S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_int_float)
6094 << RHSType << RHS.get()->getSourceRange();
6095 return QualType();
6096 }
6097
6098 // If both types are identical, no conversion is needed.
6099 if (LHSType == RHSType)
6100 return LHSType;
6101
6102 // Now handle "real" floating types (i.e. float, double, long double).
6103 if (LHSType->isRealFloatingType() || RHSType->isRealFloatingType())
6104 return handleFloatConversion(S, LHS, RHS, LHSType, RHSType,
6105 /*IsCompAssign = */ false);
6106
6107 // Finally, we have two differing integer types.
6108 return handleIntegerConversion<doIntegralCast, doIntegralCast>
6109 (S, LHS, RHS, LHSType, RHSType, /*IsCompAssign = */ false);
6110 }
6111
6112 /// \brief Convert scalar operands to a vector that matches the
6113 /// condition in length.
6114 ///
6115 /// Used when handling the OpenCL conditional operator where the
6116 /// condition is a vector while the other operands are scalar.
6117 ///
6118 /// We first compute the "result type" for the scalar operands
6119 /// according to OpenCL v1.1 s6.3.i. Both operands are then converted
6120 /// into a vector of that type where the length matches the condition
6121 /// vector type. s6.11.6 requires that the element types of the result
6122 /// and the condition must have the same number of bits.
6123 static QualType
OpenCLConvertScalarsToVectors(Sema & S,ExprResult & LHS,ExprResult & RHS,QualType CondTy,SourceLocation QuestionLoc)6124 OpenCLConvertScalarsToVectors(Sema &S, ExprResult &LHS, ExprResult &RHS,
6125 QualType CondTy, SourceLocation QuestionLoc) {
6126 QualType ResTy = OpenCLArithmeticConversions(S, LHS, RHS, QuestionLoc);
6127 if (ResTy.isNull()) return QualType();
6128
6129 const VectorType *CV = CondTy->getAs<VectorType>();
6130 assert(CV);
6131
6132 // Determine the vector result type
6133 unsigned NumElements = CV->getNumElements();
6134 QualType VectorTy = S.Context.getExtVectorType(ResTy, NumElements);
6135
6136 // Ensure that all types have the same number of bits
6137 if (S.Context.getTypeSize(CV->getElementType())
6138 != S.Context.getTypeSize(ResTy)) {
6139 // Since VectorTy is created internally, it does not pretty print
6140 // with an OpenCL name. Instead, we just print a description.
6141 std::string EleTyName = ResTy.getUnqualifiedType().getAsString();
6142 SmallString<64> Str;
6143 llvm::raw_svector_ostream OS(Str);
6144 OS << "(vector of " << NumElements << " '" << EleTyName << "' values)";
6145 S.Diag(QuestionLoc, diag::err_conditional_vector_element_size)
6146 << CondTy << OS.str();
6147 return QualType();
6148 }
6149
6150 // Convert operands to the vector result type
6151 LHS = S.ImpCastExprToType(LHS.get(), VectorTy, CK_VectorSplat);
6152 RHS = S.ImpCastExprToType(RHS.get(), VectorTy, CK_VectorSplat);
6153
6154 return VectorTy;
6155 }
6156
6157 /// \brief Return false if this is a valid OpenCL condition vector
checkOpenCLConditionVector(Sema & S,Expr * Cond,SourceLocation QuestionLoc)6158 static bool checkOpenCLConditionVector(Sema &S, Expr *Cond,
6159 SourceLocation QuestionLoc) {
6160 // OpenCL v1.1 s6.11.6 says the elements of the vector must be of
6161 // integral type.
6162 const VectorType *CondTy = Cond->getType()->getAs<VectorType>();
6163 assert(CondTy);
6164 QualType EleTy = CondTy->getElementType();
6165 if (EleTy->isIntegerType()) return false;
6166
6167 S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_nonfloat)
6168 << Cond->getType() << Cond->getSourceRange();
6169 return true;
6170 }
6171
6172 /// \brief Return false if the vector condition type and the vector
6173 /// result type are compatible.
6174 ///
6175 /// OpenCL v1.1 s6.11.6 requires that both vector types have the same
6176 /// number of elements, and their element types have the same number
6177 /// of bits.
checkVectorResult(Sema & S,QualType CondTy,QualType VecResTy,SourceLocation QuestionLoc)6178 static bool checkVectorResult(Sema &S, QualType CondTy, QualType VecResTy,
6179 SourceLocation QuestionLoc) {
6180 const VectorType *CV = CondTy->getAs<VectorType>();
6181 const VectorType *RV = VecResTy->getAs<VectorType>();
6182 assert(CV && RV);
6183
6184 if (CV->getNumElements() != RV->getNumElements()) {
6185 S.Diag(QuestionLoc, diag::err_conditional_vector_size)
6186 << CondTy << VecResTy;
6187 return true;
6188 }
6189
6190 QualType CVE = CV->getElementType();
6191 QualType RVE = RV->getElementType();
6192
6193 if (S.Context.getTypeSize(CVE) != S.Context.getTypeSize(RVE)) {
6194 S.Diag(QuestionLoc, diag::err_conditional_vector_element_size)
6195 << CondTy << VecResTy;
6196 return true;
6197 }
6198
6199 return false;
6200 }
6201
6202 /// \brief Return the resulting type for the conditional operator in
6203 /// OpenCL (aka "ternary selection operator", OpenCL v1.1
6204 /// s6.3.i) when the condition is a vector type.
6205 static QualType
OpenCLCheckVectorConditional(Sema & S,ExprResult & Cond,ExprResult & LHS,ExprResult & RHS,SourceLocation QuestionLoc)6206 OpenCLCheckVectorConditional(Sema &S, ExprResult &Cond,
6207 ExprResult &LHS, ExprResult &RHS,
6208 SourceLocation QuestionLoc) {
6209 Cond = S.DefaultFunctionArrayLvalueConversion(Cond.get());
6210 if (Cond.isInvalid())
6211 return QualType();
6212 QualType CondTy = Cond.get()->getType();
6213
6214 if (checkOpenCLConditionVector(S, Cond.get(), QuestionLoc))
6215 return QualType();
6216
6217 // If either operand is a vector then find the vector type of the
6218 // result as specified in OpenCL v1.1 s6.3.i.
6219 if (LHS.get()->getType()->isVectorType() ||
6220 RHS.get()->getType()->isVectorType()) {
6221 QualType VecResTy = S.CheckVectorOperands(LHS, RHS, QuestionLoc,
6222 /*isCompAssign*/false,
6223 /*AllowBothBool*/true,
6224 /*AllowBoolConversions*/false);
6225 if (VecResTy.isNull()) return QualType();
6226 // The result type must match the condition type as specified in
6227 // OpenCL v1.1 s6.11.6.
6228 if (checkVectorResult(S, CondTy, VecResTy, QuestionLoc))
6229 return QualType();
6230 return VecResTy;
6231 }
6232
6233 // Both operands are scalar.
6234 return OpenCLConvertScalarsToVectors(S, LHS, RHS, CondTy, QuestionLoc);
6235 }
6236
6237 /// Note that LHS is not null here, even if this is the gnu "x ?: y" extension.
6238 /// In that case, LHS = cond.
6239 /// C99 6.5.15
CheckConditionalOperands(ExprResult & Cond,ExprResult & LHS,ExprResult & RHS,ExprValueKind & VK,ExprObjectKind & OK,SourceLocation QuestionLoc)6240 QualType Sema::CheckConditionalOperands(ExprResult &Cond, ExprResult &LHS,
6241 ExprResult &RHS, ExprValueKind &VK,
6242 ExprObjectKind &OK,
6243 SourceLocation QuestionLoc) {
6244
6245 ExprResult LHSResult = CheckPlaceholderExpr(LHS.get());
6246 if (!LHSResult.isUsable()) return QualType();
6247 LHS = LHSResult;
6248
6249 ExprResult RHSResult = CheckPlaceholderExpr(RHS.get());
6250 if (!RHSResult.isUsable()) return QualType();
6251 RHS = RHSResult;
6252
6253 // C++ is sufficiently different to merit its own checker.
6254 if (getLangOpts().CPlusPlus)
6255 return CXXCheckConditionalOperands(Cond, LHS, RHS, VK, OK, QuestionLoc);
6256
6257 VK = VK_RValue;
6258 OK = OK_Ordinary;
6259
6260 // The OpenCL operator with a vector condition is sufficiently
6261 // different to merit its own checker.
6262 if (getLangOpts().OpenCL && Cond.get()->getType()->isVectorType())
6263 return OpenCLCheckVectorConditional(*this, Cond, LHS, RHS, QuestionLoc);
6264
6265 // First, check the condition.
6266 Cond = UsualUnaryConversions(Cond.get());
6267 if (Cond.isInvalid())
6268 return QualType();
6269 if (checkCondition(*this, Cond.get(), QuestionLoc))
6270 return QualType();
6271
6272 // Now check the two expressions.
6273 if (LHS.get()->getType()->isVectorType() ||
6274 RHS.get()->getType()->isVectorType())
6275 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false,
6276 /*AllowBothBool*/true,
6277 /*AllowBoolConversions*/false);
6278
6279 QualType ResTy = UsualArithmeticConversions(LHS, RHS);
6280 if (LHS.isInvalid() || RHS.isInvalid())
6281 return QualType();
6282
6283 QualType LHSTy = LHS.get()->getType();
6284 QualType RHSTy = RHS.get()->getType();
6285
6286 // If both operands have arithmetic type, do the usual arithmetic conversions
6287 // to find a common type: C99 6.5.15p3,5.
6288 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) {
6289 LHS = ImpCastExprToType(LHS.get(), ResTy, PrepareScalarCast(LHS, ResTy));
6290 RHS = ImpCastExprToType(RHS.get(), ResTy, PrepareScalarCast(RHS, ResTy));
6291
6292 return ResTy;
6293 }
6294
6295 // If both operands are the same structure or union type, the result is that
6296 // type.
6297 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3
6298 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>())
6299 if (LHSRT->getDecl() == RHSRT->getDecl())
6300 // "If both the operands have structure or union type, the result has
6301 // that type." This implies that CV qualifiers are dropped.
6302 return LHSTy.getUnqualifiedType();
6303 // FIXME: Type of conditional expression must be complete in C mode.
6304 }
6305
6306 // C99 6.5.15p5: "If both operands have void type, the result has void type."
6307 // The following || allows only one side to be void (a GCC-ism).
6308 if (LHSTy->isVoidType() || RHSTy->isVoidType()) {
6309 return checkConditionalVoidType(*this, LHS, RHS);
6310 }
6311
6312 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has
6313 // the type of the other operand."
6314 if (!checkConditionalNullPointer(*this, RHS, LHSTy)) return LHSTy;
6315 if (!checkConditionalNullPointer(*this, LHS, RHSTy)) return RHSTy;
6316
6317 // All objective-c pointer type analysis is done here.
6318 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS,
6319 QuestionLoc);
6320 if (LHS.isInvalid() || RHS.isInvalid())
6321 return QualType();
6322 if (!compositeType.isNull())
6323 return compositeType;
6324
6325
6326 // Handle block pointer types.
6327 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType())
6328 return checkConditionalBlockPointerCompatibility(*this, LHS, RHS,
6329 QuestionLoc);
6330
6331 // Check constraints for C object pointers types (C99 6.5.15p3,6).
6332 if (LHSTy->isPointerType() && RHSTy->isPointerType())
6333 return checkConditionalObjectPointersCompatibility(*this, LHS, RHS,
6334 QuestionLoc);
6335
6336 // GCC compatibility: soften pointer/integer mismatch. Note that
6337 // null pointers have been filtered out by this point.
6338 if (checkPointerIntegerMismatch(*this, LHS, RHS.get(), QuestionLoc,
6339 /*isIntFirstExpr=*/true))
6340 return RHSTy;
6341 if (checkPointerIntegerMismatch(*this, RHS, LHS.get(), QuestionLoc,
6342 /*isIntFirstExpr=*/false))
6343 return LHSTy;
6344
6345 // Emit a better diagnostic if one of the expressions is a null pointer
6346 // constant and the other is not a pointer type. In this case, the user most
6347 // likely forgot to take the address of the other expression.
6348 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc))
6349 return QualType();
6350
6351 // Otherwise, the operands are not compatible.
6352 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
6353 << LHSTy << RHSTy << LHS.get()->getSourceRange()
6354 << RHS.get()->getSourceRange();
6355 return QualType();
6356 }
6357
6358 /// FindCompositeObjCPointerType - Helper method to find composite type of
6359 /// two objective-c pointer types of the two input expressions.
FindCompositeObjCPointerType(ExprResult & LHS,ExprResult & RHS,SourceLocation QuestionLoc)6360 QualType Sema::FindCompositeObjCPointerType(ExprResult &LHS, ExprResult &RHS,
6361 SourceLocation QuestionLoc) {
6362 QualType LHSTy = LHS.get()->getType();
6363 QualType RHSTy = RHS.get()->getType();
6364
6365 // Handle things like Class and struct objc_class*. Here we case the result
6366 // to the pseudo-builtin, because that will be implicitly cast back to the
6367 // redefinition type if an attempt is made to access its fields.
6368 if (LHSTy->isObjCClassType() &&
6369 (Context.hasSameType(RHSTy, Context.getObjCClassRedefinitionType()))) {
6370 RHS = ImpCastExprToType(RHS.get(), LHSTy, CK_CPointerToObjCPointerCast);
6371 return LHSTy;
6372 }
6373 if (RHSTy->isObjCClassType() &&
6374 (Context.hasSameType(LHSTy, Context.getObjCClassRedefinitionType()))) {
6375 LHS = ImpCastExprToType(LHS.get(), RHSTy, CK_CPointerToObjCPointerCast);
6376 return RHSTy;
6377 }
6378 // And the same for struct objc_object* / id
6379 if (LHSTy->isObjCIdType() &&
6380 (Context.hasSameType(RHSTy, Context.getObjCIdRedefinitionType()))) {
6381 RHS = ImpCastExprToType(RHS.get(), LHSTy, CK_CPointerToObjCPointerCast);
6382 return LHSTy;
6383 }
6384 if (RHSTy->isObjCIdType() &&
6385 (Context.hasSameType(LHSTy, Context.getObjCIdRedefinitionType()))) {
6386 LHS = ImpCastExprToType(LHS.get(), RHSTy, CK_CPointerToObjCPointerCast);
6387 return RHSTy;
6388 }
6389 // And the same for struct objc_selector* / SEL
6390 if (Context.isObjCSelType(LHSTy) &&
6391 (Context.hasSameType(RHSTy, Context.getObjCSelRedefinitionType()))) {
6392 RHS = ImpCastExprToType(RHS.get(), LHSTy, CK_BitCast);
6393 return LHSTy;
6394 }
6395 if (Context.isObjCSelType(RHSTy) &&
6396 (Context.hasSameType(LHSTy, Context.getObjCSelRedefinitionType()))) {
6397 LHS = ImpCastExprToType(LHS.get(), RHSTy, CK_BitCast);
6398 return RHSTy;
6399 }
6400 // Check constraints for Objective-C object pointers types.
6401 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) {
6402
6403 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) {
6404 // Two identical object pointer types are always compatible.
6405 return LHSTy;
6406 }
6407 const ObjCObjectPointerType *LHSOPT = LHSTy->castAs<ObjCObjectPointerType>();
6408 const ObjCObjectPointerType *RHSOPT = RHSTy->castAs<ObjCObjectPointerType>();
6409 QualType compositeType = LHSTy;
6410
6411 // If both operands are interfaces and either operand can be
6412 // assigned to the other, use that type as the composite
6413 // type. This allows
6414 // xxx ? (A*) a : (B*) b
6415 // where B is a subclass of A.
6416 //
6417 // Additionally, as for assignment, if either type is 'id'
6418 // allow silent coercion. Finally, if the types are
6419 // incompatible then make sure to use 'id' as the composite
6420 // type so the result is acceptable for sending messages to.
6421
6422 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'.
6423 // It could return the composite type.
6424 if (!(compositeType =
6425 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) {
6426 // Nothing more to do.
6427 } else if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) {
6428 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy;
6429 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) {
6430 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy;
6431 } else if ((LHSTy->isObjCQualifiedIdType() ||
6432 RHSTy->isObjCQualifiedIdType()) &&
6433 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) {
6434 // Need to handle "id<xx>" explicitly.
6435 // GCC allows qualified id and any Objective-C type to devolve to
6436 // id. Currently localizing to here until clear this should be
6437 // part of ObjCQualifiedIdTypesAreCompatible.
6438 compositeType = Context.getObjCIdType();
6439 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) {
6440 compositeType = Context.getObjCIdType();
6441 } else {
6442 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands)
6443 << LHSTy << RHSTy
6444 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
6445 QualType incompatTy = Context.getObjCIdType();
6446 LHS = ImpCastExprToType(LHS.get(), incompatTy, CK_BitCast);
6447 RHS = ImpCastExprToType(RHS.get(), incompatTy, CK_BitCast);
6448 return incompatTy;
6449 }
6450 // The object pointer types are compatible.
6451 LHS = ImpCastExprToType(LHS.get(), compositeType, CK_BitCast);
6452 RHS = ImpCastExprToType(RHS.get(), compositeType, CK_BitCast);
6453 return compositeType;
6454 }
6455 // Check Objective-C object pointer types and 'void *'
6456 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) {
6457 if (getLangOpts().ObjCAutoRefCount) {
6458 // ARC forbids the implicit conversion of object pointers to 'void *',
6459 // so these types are not compatible.
6460 Diag(QuestionLoc, diag::err_cond_voidptr_arc) << LHSTy << RHSTy
6461 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
6462 LHS = RHS = true;
6463 return QualType();
6464 }
6465 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType();
6466 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType();
6467 QualType destPointee
6468 = Context.getQualifiedType(lhptee, rhptee.getQualifiers());
6469 QualType destType = Context.getPointerType(destPointee);
6470 // Add qualifiers if necessary.
6471 LHS = ImpCastExprToType(LHS.get(), destType, CK_NoOp);
6472 // Promote to void*.
6473 RHS = ImpCastExprToType(RHS.get(), destType, CK_BitCast);
6474 return destType;
6475 }
6476 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) {
6477 if (getLangOpts().ObjCAutoRefCount) {
6478 // ARC forbids the implicit conversion of object pointers to 'void *',
6479 // so these types are not compatible.
6480 Diag(QuestionLoc, diag::err_cond_voidptr_arc) << LHSTy << RHSTy
6481 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
6482 LHS = RHS = true;
6483 return QualType();
6484 }
6485 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType();
6486 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType();
6487 QualType destPointee
6488 = Context.getQualifiedType(rhptee, lhptee.getQualifiers());
6489 QualType destType = Context.getPointerType(destPointee);
6490 // Add qualifiers if necessary.
6491 RHS = ImpCastExprToType(RHS.get(), destType, CK_NoOp);
6492 // Promote to void*.
6493 LHS = ImpCastExprToType(LHS.get(), destType, CK_BitCast);
6494 return destType;
6495 }
6496 return QualType();
6497 }
6498
6499 /// SuggestParentheses - Emit a note with a fixit hint that wraps
6500 /// ParenRange in parentheses.
SuggestParentheses(Sema & Self,SourceLocation Loc,const PartialDiagnostic & Note,SourceRange ParenRange)6501 static void SuggestParentheses(Sema &Self, SourceLocation Loc,
6502 const PartialDiagnostic &Note,
6503 SourceRange ParenRange) {
6504 SourceLocation EndLoc = Self.getLocForEndOfToken(ParenRange.getEnd());
6505 if (ParenRange.getBegin().isFileID() && ParenRange.getEnd().isFileID() &&
6506 EndLoc.isValid()) {
6507 Self.Diag(Loc, Note)
6508 << FixItHint::CreateInsertion(ParenRange.getBegin(), "(")
6509 << FixItHint::CreateInsertion(EndLoc, ")");
6510 } else {
6511 // We can't display the parentheses, so just show the bare note.
6512 Self.Diag(Loc, Note) << ParenRange;
6513 }
6514 }
6515
IsArithmeticOp(BinaryOperatorKind Opc)6516 static bool IsArithmeticOp(BinaryOperatorKind Opc) {
6517 return BinaryOperator::isAdditiveOp(Opc) ||
6518 BinaryOperator::isMultiplicativeOp(Opc) ||
6519 BinaryOperator::isShiftOp(Opc);
6520 }
6521
6522 /// IsArithmeticBinaryExpr - Returns true if E is an arithmetic binary
6523 /// expression, either using a built-in or overloaded operator,
6524 /// and sets *OpCode to the opcode and *RHSExprs to the right-hand side
6525 /// expression.
IsArithmeticBinaryExpr(Expr * E,BinaryOperatorKind * Opcode,Expr ** RHSExprs)6526 static bool IsArithmeticBinaryExpr(Expr *E, BinaryOperatorKind *Opcode,
6527 Expr **RHSExprs) {
6528 // Don't strip parenthesis: we should not warn if E is in parenthesis.
6529 E = E->IgnoreImpCasts();
6530 E = E->IgnoreConversionOperator();
6531 E = E->IgnoreImpCasts();
6532
6533 // Built-in binary operator.
6534 if (BinaryOperator *OP = dyn_cast<BinaryOperator>(E)) {
6535 if (IsArithmeticOp(OP->getOpcode())) {
6536 *Opcode = OP->getOpcode();
6537 *RHSExprs = OP->getRHS();
6538 return true;
6539 }
6540 }
6541
6542 // Overloaded operator.
6543 if (CXXOperatorCallExpr *Call = dyn_cast<CXXOperatorCallExpr>(E)) {
6544 if (Call->getNumArgs() != 2)
6545 return false;
6546
6547 // Make sure this is really a binary operator that is safe to pass into
6548 // BinaryOperator::getOverloadedOpcode(), e.g. it's not a subscript op.
6549 OverloadedOperatorKind OO = Call->getOperator();
6550 if (OO < OO_Plus || OO > OO_Arrow ||
6551 OO == OO_PlusPlus || OO == OO_MinusMinus)
6552 return false;
6553
6554 BinaryOperatorKind OpKind = BinaryOperator::getOverloadedOpcode(OO);
6555 if (IsArithmeticOp(OpKind)) {
6556 *Opcode = OpKind;
6557 *RHSExprs = Call->getArg(1);
6558 return true;
6559 }
6560 }
6561
6562 return false;
6563 }
6564
6565 /// ExprLooksBoolean - Returns true if E looks boolean, i.e. it has boolean type
6566 /// or is a logical expression such as (x==y) which has int type, but is
6567 /// commonly interpreted as boolean.
ExprLooksBoolean(Expr * E)6568 static bool ExprLooksBoolean(Expr *E) {
6569 E = E->IgnoreParenImpCasts();
6570
6571 if (E->getType()->isBooleanType())
6572 return true;
6573 if (BinaryOperator *OP = dyn_cast<BinaryOperator>(E))
6574 return OP->isComparisonOp() || OP->isLogicalOp();
6575 if (UnaryOperator *OP = dyn_cast<UnaryOperator>(E))
6576 return OP->getOpcode() == UO_LNot;
6577 if (E->getType()->isPointerType())
6578 return true;
6579
6580 return false;
6581 }
6582
6583 /// DiagnoseConditionalPrecedence - Emit a warning when a conditional operator
6584 /// and binary operator are mixed in a way that suggests the programmer assumed
6585 /// the conditional operator has higher precedence, for example:
6586 /// "int x = a + someBinaryCondition ? 1 : 2".
DiagnoseConditionalPrecedence(Sema & Self,SourceLocation OpLoc,Expr * Condition,Expr * LHSExpr,Expr * RHSExpr)6587 static void DiagnoseConditionalPrecedence(Sema &Self,
6588 SourceLocation OpLoc,
6589 Expr *Condition,
6590 Expr *LHSExpr,
6591 Expr *RHSExpr) {
6592 BinaryOperatorKind CondOpcode;
6593 Expr *CondRHS;
6594
6595 if (!IsArithmeticBinaryExpr(Condition, &CondOpcode, &CondRHS))
6596 return;
6597 if (!ExprLooksBoolean(CondRHS))
6598 return;
6599
6600 // The condition is an arithmetic binary expression, with a right-
6601 // hand side that looks boolean, so warn.
6602
6603 Self.Diag(OpLoc, diag::warn_precedence_conditional)
6604 << Condition->getSourceRange()
6605 << BinaryOperator::getOpcodeStr(CondOpcode);
6606
6607 SuggestParentheses(Self, OpLoc,
6608 Self.PDiag(diag::note_precedence_silence)
6609 << BinaryOperator::getOpcodeStr(CondOpcode),
6610 SourceRange(Condition->getLocStart(), Condition->getLocEnd()));
6611
6612 SuggestParentheses(Self, OpLoc,
6613 Self.PDiag(diag::note_precedence_conditional_first),
6614 SourceRange(CondRHS->getLocStart(), RHSExpr->getLocEnd()));
6615 }
6616
6617 /// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null
6618 /// in the case of a the GNU conditional expr extension.
ActOnConditionalOp(SourceLocation QuestionLoc,SourceLocation ColonLoc,Expr * CondExpr,Expr * LHSExpr,Expr * RHSExpr)6619 ExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc,
6620 SourceLocation ColonLoc,
6621 Expr *CondExpr, Expr *LHSExpr,
6622 Expr *RHSExpr) {
6623 if (!getLangOpts().CPlusPlus) {
6624 // C cannot handle TypoExpr nodes in the condition because it
6625 // doesn't handle dependent types properly, so make sure any TypoExprs have
6626 // been dealt with before checking the operands.
6627 ExprResult CondResult = CorrectDelayedTyposInExpr(CondExpr);
6628 if (!CondResult.isUsable()) return ExprError();
6629 CondExpr = CondResult.get();
6630 }
6631
6632 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS
6633 // was the condition.
6634 OpaqueValueExpr *opaqueValue = nullptr;
6635 Expr *commonExpr = nullptr;
6636 if (!LHSExpr) {
6637 commonExpr = CondExpr;
6638 // Lower out placeholder types first. This is important so that we don't
6639 // try to capture a placeholder. This happens in few cases in C++; such
6640 // as Objective-C++'s dictionary subscripting syntax.
6641 if (commonExpr->hasPlaceholderType()) {
6642 ExprResult result = CheckPlaceholderExpr(commonExpr);
6643 if (!result.isUsable()) return ExprError();
6644 commonExpr = result.get();
6645 }
6646 // We usually want to apply unary conversions *before* saving, except
6647 // in the special case of a C++ l-value conditional.
6648 if (!(getLangOpts().CPlusPlus
6649 && !commonExpr->isTypeDependent()
6650 && commonExpr->getValueKind() == RHSExpr->getValueKind()
6651 && commonExpr->isGLValue()
6652 && commonExpr->isOrdinaryOrBitFieldObject()
6653 && RHSExpr->isOrdinaryOrBitFieldObject()
6654 && Context.hasSameType(commonExpr->getType(), RHSExpr->getType()))) {
6655 ExprResult commonRes = UsualUnaryConversions(commonExpr);
6656 if (commonRes.isInvalid())
6657 return ExprError();
6658 commonExpr = commonRes.get();
6659 }
6660
6661 opaqueValue = new (Context) OpaqueValueExpr(commonExpr->getExprLoc(),
6662 commonExpr->getType(),
6663 commonExpr->getValueKind(),
6664 commonExpr->getObjectKind(),
6665 commonExpr);
6666 LHSExpr = CondExpr = opaqueValue;
6667 }
6668
6669 ExprValueKind VK = VK_RValue;
6670 ExprObjectKind OK = OK_Ordinary;
6671 ExprResult Cond = CondExpr, LHS = LHSExpr, RHS = RHSExpr;
6672 QualType result = CheckConditionalOperands(Cond, LHS, RHS,
6673 VK, OK, QuestionLoc);
6674 if (result.isNull() || Cond.isInvalid() || LHS.isInvalid() ||
6675 RHS.isInvalid())
6676 return ExprError();
6677
6678 DiagnoseConditionalPrecedence(*this, QuestionLoc, Cond.get(), LHS.get(),
6679 RHS.get());
6680
6681 CheckBoolLikeConversion(Cond.get(), QuestionLoc);
6682
6683 if (!commonExpr)
6684 return new (Context)
6685 ConditionalOperator(Cond.get(), QuestionLoc, LHS.get(), ColonLoc,
6686 RHS.get(), result, VK, OK);
6687
6688 return new (Context) BinaryConditionalOperator(
6689 commonExpr, opaqueValue, Cond.get(), LHS.get(), RHS.get(), QuestionLoc,
6690 ColonLoc, result, VK, OK);
6691 }
6692
6693 // checkPointerTypesForAssignment - This is a very tricky routine (despite
6694 // being closely modeled after the C99 spec:-). The odd characteristic of this
6695 // routine is it effectively iqnores the qualifiers on the top level pointee.
6696 // This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3].
6697 // FIXME: add a couple examples in this comment.
6698 static Sema::AssignConvertType
checkPointerTypesForAssignment(Sema & S,QualType LHSType,QualType RHSType)6699 checkPointerTypesForAssignment(Sema &S, QualType LHSType, QualType RHSType) {
6700 assert(LHSType.isCanonical() && "LHS not canonicalized!");
6701 assert(RHSType.isCanonical() && "RHS not canonicalized!");
6702
6703 // get the "pointed to" type (ignoring qualifiers at the top level)
6704 const Type *lhptee, *rhptee;
6705 Qualifiers lhq, rhq;
6706 std::tie(lhptee, lhq) =
6707 cast<PointerType>(LHSType)->getPointeeType().split().asPair();
6708 std::tie(rhptee, rhq) =
6709 cast<PointerType>(RHSType)->getPointeeType().split().asPair();
6710
6711 Sema::AssignConvertType ConvTy = Sema::Compatible;
6712
6713 // C99 6.5.16.1p1: This following citation is common to constraints
6714 // 3 & 4 (below). ...and the type *pointed to* by the left has all the
6715 // qualifiers of the type *pointed to* by the right;
6716
6717 // As a special case, 'non-__weak A *' -> 'non-__weak const *' is okay.
6718 if (lhq.getObjCLifetime() != rhq.getObjCLifetime() &&
6719 lhq.compatiblyIncludesObjCLifetime(rhq)) {
6720 // Ignore lifetime for further calculation.
6721 lhq.removeObjCLifetime();
6722 rhq.removeObjCLifetime();
6723 }
6724
6725 if (!lhq.compatiblyIncludes(rhq)) {
6726 // Treat address-space mismatches as fatal. TODO: address subspaces
6727 if (!lhq.isAddressSpaceSupersetOf(rhq))
6728 ConvTy = Sema::IncompatiblePointerDiscardsQualifiers;
6729
6730 // It's okay to add or remove GC or lifetime qualifiers when converting to
6731 // and from void*.
6732 else if (lhq.withoutObjCGCAttr().withoutObjCLifetime()
6733 .compatiblyIncludes(
6734 rhq.withoutObjCGCAttr().withoutObjCLifetime())
6735 && (lhptee->isVoidType() || rhptee->isVoidType()))
6736 ; // keep old
6737
6738 // Treat lifetime mismatches as fatal.
6739 else if (lhq.getObjCLifetime() != rhq.getObjCLifetime())
6740 ConvTy = Sema::IncompatiblePointerDiscardsQualifiers;
6741
6742 // For GCC compatibility, other qualifier mismatches are treated
6743 // as still compatible in C.
6744 else ConvTy = Sema::CompatiblePointerDiscardsQualifiers;
6745 }
6746
6747 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or
6748 // incomplete type and the other is a pointer to a qualified or unqualified
6749 // version of void...
6750 if (lhptee->isVoidType()) {
6751 if (rhptee->isIncompleteOrObjectType())
6752 return ConvTy;
6753
6754 // As an extension, we allow cast to/from void* to function pointer.
6755 assert(rhptee->isFunctionType());
6756 return Sema::FunctionVoidPointer;
6757 }
6758
6759 if (rhptee->isVoidType()) {
6760 if (lhptee->isIncompleteOrObjectType())
6761 return ConvTy;
6762
6763 // As an extension, we allow cast to/from void* to function pointer.
6764 assert(lhptee->isFunctionType());
6765 return Sema::FunctionVoidPointer;
6766 }
6767
6768 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or
6769 // unqualified versions of compatible types, ...
6770 QualType ltrans = QualType(lhptee, 0), rtrans = QualType(rhptee, 0);
6771 if (!S.Context.typesAreCompatible(ltrans, rtrans)) {
6772 // Check if the pointee types are compatible ignoring the sign.
6773 // We explicitly check for char so that we catch "char" vs
6774 // "unsigned char" on systems where "char" is unsigned.
6775 if (lhptee->isCharType())
6776 ltrans = S.Context.UnsignedCharTy;
6777 else if (lhptee->hasSignedIntegerRepresentation())
6778 ltrans = S.Context.getCorrespondingUnsignedType(ltrans);
6779
6780 if (rhptee->isCharType())
6781 rtrans = S.Context.UnsignedCharTy;
6782 else if (rhptee->hasSignedIntegerRepresentation())
6783 rtrans = S.Context.getCorrespondingUnsignedType(rtrans);
6784
6785 if (ltrans == rtrans) {
6786 // Types are compatible ignoring the sign. Qualifier incompatibility
6787 // takes priority over sign incompatibility because the sign
6788 // warning can be disabled.
6789 if (ConvTy != Sema::Compatible)
6790 return ConvTy;
6791
6792 return Sema::IncompatiblePointerSign;
6793 }
6794
6795 // If we are a multi-level pointer, it's possible that our issue is simply
6796 // one of qualification - e.g. char ** -> const char ** is not allowed. If
6797 // the eventual target type is the same and the pointers have the same
6798 // level of indirection, this must be the issue.
6799 if (isa<PointerType>(lhptee) && isa<PointerType>(rhptee)) {
6800 do {
6801 lhptee = cast<PointerType>(lhptee)->getPointeeType().getTypePtr();
6802 rhptee = cast<PointerType>(rhptee)->getPointeeType().getTypePtr();
6803 } while (isa<PointerType>(lhptee) && isa<PointerType>(rhptee));
6804
6805 if (lhptee == rhptee)
6806 return Sema::IncompatibleNestedPointerQualifiers;
6807 }
6808
6809 // General pointer incompatibility takes priority over qualifiers.
6810 return Sema::IncompatiblePointer;
6811 }
6812 if (!S.getLangOpts().CPlusPlus &&
6813 S.IsNoReturnConversion(ltrans, rtrans, ltrans))
6814 return Sema::IncompatiblePointer;
6815 return ConvTy;
6816 }
6817
6818 /// checkBlockPointerTypesForAssignment - This routine determines whether two
6819 /// block pointer types are compatible or whether a block and normal pointer
6820 /// are compatible. It is more restrict than comparing two function pointer
6821 // types.
6822 static Sema::AssignConvertType
checkBlockPointerTypesForAssignment(Sema & S,QualType LHSType,QualType RHSType)6823 checkBlockPointerTypesForAssignment(Sema &S, QualType LHSType,
6824 QualType RHSType) {
6825 assert(LHSType.isCanonical() && "LHS not canonicalized!");
6826 assert(RHSType.isCanonical() && "RHS not canonicalized!");
6827
6828 QualType lhptee, rhptee;
6829
6830 // get the "pointed to" type (ignoring qualifiers at the top level)
6831 lhptee = cast<BlockPointerType>(LHSType)->getPointeeType();
6832 rhptee = cast<BlockPointerType>(RHSType)->getPointeeType();
6833
6834 // In C++, the types have to match exactly.
6835 if (S.getLangOpts().CPlusPlus)
6836 return Sema::IncompatibleBlockPointer;
6837
6838 Sema::AssignConvertType ConvTy = Sema::Compatible;
6839
6840 // For blocks we enforce that qualifiers are identical.
6841 if (lhptee.getLocalQualifiers() != rhptee.getLocalQualifiers())
6842 ConvTy = Sema::CompatiblePointerDiscardsQualifiers;
6843
6844 if (!S.Context.typesAreBlockPointerCompatible(LHSType, RHSType))
6845 return Sema::IncompatibleBlockPointer;
6846
6847 return ConvTy;
6848 }
6849
6850 /// checkObjCPointerTypesForAssignment - Compares two objective-c pointer types
6851 /// for assignment compatibility.
6852 static Sema::AssignConvertType
checkObjCPointerTypesForAssignment(Sema & S,QualType LHSType,QualType RHSType)6853 checkObjCPointerTypesForAssignment(Sema &S, QualType LHSType,
6854 QualType RHSType) {
6855 assert(LHSType.isCanonical() && "LHS was not canonicalized!");
6856 assert(RHSType.isCanonical() && "RHS was not canonicalized!");
6857
6858 if (LHSType->isObjCBuiltinType()) {
6859 // Class is not compatible with ObjC object pointers.
6860 if (LHSType->isObjCClassType() && !RHSType->isObjCBuiltinType() &&
6861 !RHSType->isObjCQualifiedClassType())
6862 return Sema::IncompatiblePointer;
6863 return Sema::Compatible;
6864 }
6865 if (RHSType->isObjCBuiltinType()) {
6866 if (RHSType->isObjCClassType() && !LHSType->isObjCBuiltinType() &&
6867 !LHSType->isObjCQualifiedClassType())
6868 return Sema::IncompatiblePointer;
6869 return Sema::Compatible;
6870 }
6871 QualType lhptee = LHSType->getAs<ObjCObjectPointerType>()->getPointeeType();
6872 QualType rhptee = RHSType->getAs<ObjCObjectPointerType>()->getPointeeType();
6873
6874 if (!lhptee.isAtLeastAsQualifiedAs(rhptee) &&
6875 // make an exception for id<P>
6876 !LHSType->isObjCQualifiedIdType())
6877 return Sema::CompatiblePointerDiscardsQualifiers;
6878
6879 if (S.Context.typesAreCompatible(LHSType, RHSType))
6880 return Sema::Compatible;
6881 if (LHSType->isObjCQualifiedIdType() || RHSType->isObjCQualifiedIdType())
6882 return Sema::IncompatibleObjCQualifiedId;
6883 return Sema::IncompatiblePointer;
6884 }
6885
6886 Sema::AssignConvertType
CheckAssignmentConstraints(SourceLocation Loc,QualType LHSType,QualType RHSType)6887 Sema::CheckAssignmentConstraints(SourceLocation Loc,
6888 QualType LHSType, QualType RHSType) {
6889 // Fake up an opaque expression. We don't actually care about what
6890 // cast operations are required, so if CheckAssignmentConstraints
6891 // adds casts to this they'll be wasted, but fortunately that doesn't
6892 // usually happen on valid code.
6893 OpaqueValueExpr RHSExpr(Loc, RHSType, VK_RValue);
6894 ExprResult RHSPtr = &RHSExpr;
6895 CastKind K = CK_Invalid;
6896
6897 return CheckAssignmentConstraints(LHSType, RHSPtr, K, /*ConvertRHS=*/false);
6898 }
6899
6900 /// CheckAssignmentConstraints (C99 6.5.16) - This routine currently
6901 /// has code to accommodate several GCC extensions when type checking
6902 /// pointers. Here are some objectionable examples that GCC considers warnings:
6903 ///
6904 /// int a, *pint;
6905 /// short *pshort;
6906 /// struct foo *pfoo;
6907 ///
6908 /// pint = pshort; // warning: assignment from incompatible pointer type
6909 /// a = pint; // warning: assignment makes integer from pointer without a cast
6910 /// pint = a; // warning: assignment makes pointer from integer without a cast
6911 /// pint = pfoo; // warning: assignment from incompatible pointer type
6912 ///
6913 /// As a result, the code for dealing with pointers is more complex than the
6914 /// C99 spec dictates.
6915 ///
6916 /// Sets 'Kind' for any result kind except Incompatible.
6917 Sema::AssignConvertType
CheckAssignmentConstraints(QualType LHSType,ExprResult & RHS,CastKind & Kind,bool ConvertRHS)6918 Sema::CheckAssignmentConstraints(QualType LHSType, ExprResult &RHS,
6919 CastKind &Kind, bool ConvertRHS) {
6920 QualType RHSType = RHS.get()->getType();
6921 QualType OrigLHSType = LHSType;
6922
6923 // Get canonical types. We're not formatting these types, just comparing
6924 // them.
6925 LHSType = Context.getCanonicalType(LHSType).getUnqualifiedType();
6926 RHSType = Context.getCanonicalType(RHSType).getUnqualifiedType();
6927
6928 // Common case: no conversion required.
6929 if (LHSType == RHSType) {
6930 Kind = CK_NoOp;
6931 return Compatible;
6932 }
6933
6934 // If we have an atomic type, try a non-atomic assignment, then just add an
6935 // atomic qualification step.
6936 if (const AtomicType *AtomicTy = dyn_cast<AtomicType>(LHSType)) {
6937 Sema::AssignConvertType result =
6938 CheckAssignmentConstraints(AtomicTy->getValueType(), RHS, Kind);
6939 if (result != Compatible)
6940 return result;
6941 if (Kind != CK_NoOp && ConvertRHS)
6942 RHS = ImpCastExprToType(RHS.get(), AtomicTy->getValueType(), Kind);
6943 Kind = CK_NonAtomicToAtomic;
6944 return Compatible;
6945 }
6946
6947 // If the left-hand side is a reference type, then we are in a
6948 // (rare!) case where we've allowed the use of references in C,
6949 // e.g., as a parameter type in a built-in function. In this case,
6950 // just make sure that the type referenced is compatible with the
6951 // right-hand side type. The caller is responsible for adjusting
6952 // LHSType so that the resulting expression does not have reference
6953 // type.
6954 if (const ReferenceType *LHSTypeRef = LHSType->getAs<ReferenceType>()) {
6955 if (Context.typesAreCompatible(LHSTypeRef->getPointeeType(), RHSType)) {
6956 Kind = CK_LValueBitCast;
6957 return Compatible;
6958 }
6959 return Incompatible;
6960 }
6961
6962 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type
6963 // to the same ExtVector type.
6964 if (LHSType->isExtVectorType()) {
6965 if (RHSType->isExtVectorType())
6966 return Incompatible;
6967 if (RHSType->isArithmeticType()) {
6968 // CK_VectorSplat does T -> vector T, so first cast to the
6969 // element type.
6970 QualType elType = cast<ExtVectorType>(LHSType)->getElementType();
6971 if (elType != RHSType && ConvertRHS) {
6972 Kind = PrepareScalarCast(RHS, elType);
6973 RHS = ImpCastExprToType(RHS.get(), elType, Kind);
6974 }
6975 Kind = CK_VectorSplat;
6976 return Compatible;
6977 }
6978 }
6979
6980 // Conversions to or from vector type.
6981 if (LHSType->isVectorType() || RHSType->isVectorType()) {
6982 if (LHSType->isVectorType() && RHSType->isVectorType()) {
6983 // Allow assignments of an AltiVec vector type to an equivalent GCC
6984 // vector type and vice versa
6985 if (Context.areCompatibleVectorTypes(LHSType, RHSType)) {
6986 Kind = CK_BitCast;
6987 return Compatible;
6988 }
6989
6990 // If we are allowing lax vector conversions, and LHS and RHS are both
6991 // vectors, the total size only needs to be the same. This is a bitcast;
6992 // no bits are changed but the result type is different.
6993 if (isLaxVectorConversion(RHSType, LHSType)) {
6994 Kind = CK_BitCast;
6995 return IncompatibleVectors;
6996 }
6997 }
6998 return Incompatible;
6999 }
7000
7001 // Arithmetic conversions.
7002 if (LHSType->isArithmeticType() && RHSType->isArithmeticType() &&
7003 !(getLangOpts().CPlusPlus && LHSType->isEnumeralType())) {
7004 if (ConvertRHS)
7005 Kind = PrepareScalarCast(RHS, LHSType);
7006 return Compatible;
7007 }
7008
7009 // Conversions to normal pointers.
7010 if (const PointerType *LHSPointer = dyn_cast<PointerType>(LHSType)) {
7011 // U* -> T*
7012 if (isa<PointerType>(RHSType)) {
7013 unsigned AddrSpaceL = LHSPointer->getPointeeType().getAddressSpace();
7014 unsigned AddrSpaceR = RHSType->getPointeeType().getAddressSpace();
7015 Kind = AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion : CK_BitCast;
7016 return checkPointerTypesForAssignment(*this, LHSType, RHSType);
7017 }
7018
7019 // int -> T*
7020 if (RHSType->isIntegerType()) {
7021 Kind = CK_IntegralToPointer; // FIXME: null?
7022 return IntToPointer;
7023 }
7024
7025 // C pointers are not compatible with ObjC object pointers,
7026 // with two exceptions:
7027 if (isa<ObjCObjectPointerType>(RHSType)) {
7028 // - conversions to void*
7029 if (LHSPointer->getPointeeType()->isVoidType()) {
7030 Kind = CK_BitCast;
7031 return Compatible;
7032 }
7033
7034 // - conversions from 'Class' to the redefinition type
7035 if (RHSType->isObjCClassType() &&
7036 Context.hasSameType(LHSType,
7037 Context.getObjCClassRedefinitionType())) {
7038 Kind = CK_BitCast;
7039 return Compatible;
7040 }
7041
7042 Kind = CK_BitCast;
7043 return IncompatiblePointer;
7044 }
7045
7046 // U^ -> void*
7047 if (RHSType->getAs<BlockPointerType>()) {
7048 if (LHSPointer->getPointeeType()->isVoidType()) {
7049 Kind = CK_BitCast;
7050 return Compatible;
7051 }
7052 }
7053
7054 return Incompatible;
7055 }
7056
7057 // Conversions to block pointers.
7058 if (isa<BlockPointerType>(LHSType)) {
7059 // U^ -> T^
7060 if (RHSType->isBlockPointerType()) {
7061 Kind = CK_BitCast;
7062 return checkBlockPointerTypesForAssignment(*this, LHSType, RHSType);
7063 }
7064
7065 // int or null -> T^
7066 if (RHSType->isIntegerType()) {
7067 Kind = CK_IntegralToPointer; // FIXME: null
7068 return IntToBlockPointer;
7069 }
7070
7071 // id -> T^
7072 if (getLangOpts().ObjC1 && RHSType->isObjCIdType()) {
7073 Kind = CK_AnyPointerToBlockPointerCast;
7074 return Compatible;
7075 }
7076
7077 // void* -> T^
7078 if (const PointerType *RHSPT = RHSType->getAs<PointerType>())
7079 if (RHSPT->getPointeeType()->isVoidType()) {
7080 Kind = CK_AnyPointerToBlockPointerCast;
7081 return Compatible;
7082 }
7083
7084 return Incompatible;
7085 }
7086
7087 // Conversions to Objective-C pointers.
7088 if (isa<ObjCObjectPointerType>(LHSType)) {
7089 // A* -> B*
7090 if (RHSType->isObjCObjectPointerType()) {
7091 Kind = CK_BitCast;
7092 Sema::AssignConvertType result =
7093 checkObjCPointerTypesForAssignment(*this, LHSType, RHSType);
7094 if (getLangOpts().ObjCAutoRefCount &&
7095 result == Compatible &&
7096 !CheckObjCARCUnavailableWeakConversion(OrigLHSType, RHSType))
7097 result = IncompatibleObjCWeakRef;
7098 return result;
7099 }
7100
7101 // int or null -> A*
7102 if (RHSType->isIntegerType()) {
7103 Kind = CK_IntegralToPointer; // FIXME: null
7104 return IntToPointer;
7105 }
7106
7107 // In general, C pointers are not compatible with ObjC object pointers,
7108 // with two exceptions:
7109 if (isa<PointerType>(RHSType)) {
7110 Kind = CK_CPointerToObjCPointerCast;
7111
7112 // - conversions from 'void*'
7113 if (RHSType->isVoidPointerType()) {
7114 return Compatible;
7115 }
7116
7117 // - conversions to 'Class' from its redefinition type
7118 if (LHSType->isObjCClassType() &&
7119 Context.hasSameType(RHSType,
7120 Context.getObjCClassRedefinitionType())) {
7121 return Compatible;
7122 }
7123
7124 return IncompatiblePointer;
7125 }
7126
7127 // Only under strict condition T^ is compatible with an Objective-C pointer.
7128 if (RHSType->isBlockPointerType() &&
7129 LHSType->isBlockCompatibleObjCPointerType(Context)) {
7130 if (ConvertRHS)
7131 maybeExtendBlockObject(RHS);
7132 Kind = CK_BlockPointerToObjCPointerCast;
7133 return Compatible;
7134 }
7135
7136 return Incompatible;
7137 }
7138
7139 // Conversions from pointers that are not covered by the above.
7140 if (isa<PointerType>(RHSType)) {
7141 // T* -> _Bool
7142 if (LHSType == Context.BoolTy) {
7143 Kind = CK_PointerToBoolean;
7144 return Compatible;
7145 }
7146
7147 // T* -> int
7148 if (LHSType->isIntegerType()) {
7149 Kind = CK_PointerToIntegral;
7150 return PointerToInt;
7151 }
7152
7153 return Incompatible;
7154 }
7155
7156 // Conversions from Objective-C pointers that are not covered by the above.
7157 if (isa<ObjCObjectPointerType>(RHSType)) {
7158 // T* -> _Bool
7159 if (LHSType == Context.BoolTy) {
7160 Kind = CK_PointerToBoolean;
7161 return Compatible;
7162 }
7163
7164 // T* -> int
7165 if (LHSType->isIntegerType()) {
7166 Kind = CK_PointerToIntegral;
7167 return PointerToInt;
7168 }
7169
7170 return Incompatible;
7171 }
7172
7173 // struct A -> struct B
7174 if (isa<TagType>(LHSType) && isa<TagType>(RHSType)) {
7175 if (Context.typesAreCompatible(LHSType, RHSType)) {
7176 Kind = CK_NoOp;
7177 return Compatible;
7178 }
7179 }
7180
7181 return Incompatible;
7182 }
7183
7184 /// \brief Constructs a transparent union from an expression that is
7185 /// used to initialize the transparent union.
ConstructTransparentUnion(Sema & S,ASTContext & C,ExprResult & EResult,QualType UnionType,FieldDecl * Field)7186 static void ConstructTransparentUnion(Sema &S, ASTContext &C,
7187 ExprResult &EResult, QualType UnionType,
7188 FieldDecl *Field) {
7189 // Build an initializer list that designates the appropriate member
7190 // of the transparent union.
7191 Expr *E = EResult.get();
7192 InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(),
7193 E, SourceLocation());
7194 Initializer->setType(UnionType);
7195 Initializer->setInitializedFieldInUnion(Field);
7196
7197 // Build a compound literal constructing a value of the transparent
7198 // union type from this initializer list.
7199 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType);
7200 EResult = new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType,
7201 VK_RValue, Initializer, false);
7202 }
7203
7204 Sema::AssignConvertType
CheckTransparentUnionArgumentConstraints(QualType ArgType,ExprResult & RHS)7205 Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType,
7206 ExprResult &RHS) {
7207 QualType RHSType = RHS.get()->getType();
7208
7209 // If the ArgType is a Union type, we want to handle a potential
7210 // transparent_union GCC extension.
7211 const RecordType *UT = ArgType->getAsUnionType();
7212 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>())
7213 return Incompatible;
7214
7215 // The field to initialize within the transparent union.
7216 RecordDecl *UD = UT->getDecl();
7217 FieldDecl *InitField = nullptr;
7218 // It's compatible if the expression matches any of the fields.
7219 for (auto *it : UD->fields()) {
7220 if (it->getType()->isPointerType()) {
7221 // If the transparent union contains a pointer type, we allow:
7222 // 1) void pointer
7223 // 2) null pointer constant
7224 if (RHSType->isPointerType())
7225 if (RHSType->castAs<PointerType>()->getPointeeType()->isVoidType()) {
7226 RHS = ImpCastExprToType(RHS.get(), it->getType(), CK_BitCast);
7227 InitField = it;
7228 break;
7229 }
7230
7231 if (RHS.get()->isNullPointerConstant(Context,
7232 Expr::NPC_ValueDependentIsNull)) {
7233 RHS = ImpCastExprToType(RHS.get(), it->getType(),
7234 CK_NullToPointer);
7235 InitField = it;
7236 break;
7237 }
7238 }
7239
7240 CastKind Kind = CK_Invalid;
7241 if (CheckAssignmentConstraints(it->getType(), RHS, Kind)
7242 == Compatible) {
7243 RHS = ImpCastExprToType(RHS.get(), it->getType(), Kind);
7244 InitField = it;
7245 break;
7246 }
7247 }
7248
7249 if (!InitField)
7250 return Incompatible;
7251
7252 ConstructTransparentUnion(*this, Context, RHS, ArgType, InitField);
7253 return Compatible;
7254 }
7255
7256 Sema::AssignConvertType
CheckSingleAssignmentConstraints(QualType LHSType,ExprResult & CallerRHS,bool Diagnose,bool DiagnoseCFAudited,bool ConvertRHS)7257 Sema::CheckSingleAssignmentConstraints(QualType LHSType, ExprResult &CallerRHS,
7258 bool Diagnose,
7259 bool DiagnoseCFAudited,
7260 bool ConvertRHS) {
7261 // If ConvertRHS is false, we want to leave the caller's RHS untouched. Sadly,
7262 // we can't avoid *all* modifications at the moment, so we need some somewhere
7263 // to put the updated value.
7264 ExprResult LocalRHS = CallerRHS;
7265 ExprResult &RHS = ConvertRHS ? CallerRHS : LocalRHS;
7266
7267 if (getLangOpts().CPlusPlus) {
7268 if (!LHSType->isRecordType() && !LHSType->isAtomicType()) {
7269 // C++ 5.17p3: If the left operand is not of class type, the
7270 // expression is implicitly converted (C++ 4) to the
7271 // cv-unqualified type of the left operand.
7272 ExprResult Res;
7273 if (Diagnose) {
7274 Res = PerformImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(),
7275 AA_Assigning);
7276 } else {
7277 ImplicitConversionSequence ICS =
7278 TryImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(),
7279 /*SuppressUserConversions=*/false,
7280 /*AllowExplicit=*/false,
7281 /*InOverloadResolution=*/false,
7282 /*CStyle=*/false,
7283 /*AllowObjCWritebackConversion=*/false);
7284 if (ICS.isFailure())
7285 return Incompatible;
7286 Res = PerformImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(),
7287 ICS, AA_Assigning);
7288 }
7289 if (Res.isInvalid())
7290 return Incompatible;
7291 Sema::AssignConvertType result = Compatible;
7292 if (getLangOpts().ObjCAutoRefCount &&
7293 !CheckObjCARCUnavailableWeakConversion(LHSType,
7294 RHS.get()->getType()))
7295 result = IncompatibleObjCWeakRef;
7296 RHS = Res;
7297 return result;
7298 }
7299
7300 // FIXME: Currently, we fall through and treat C++ classes like C
7301 // structures.
7302 // FIXME: We also fall through for atomics; not sure what should
7303 // happen there, though.
7304 } else if (RHS.get()->getType() == Context.OverloadTy) {
7305 // As a set of extensions to C, we support overloading on functions. These
7306 // functions need to be resolved here.
7307 DeclAccessPair DAP;
7308 if (FunctionDecl *FD = ResolveAddressOfOverloadedFunction(
7309 RHS.get(), LHSType, /*Complain=*/false, DAP))
7310 RHS = FixOverloadedFunctionReference(RHS.get(), DAP, FD);
7311 else
7312 return Incompatible;
7313 }
7314
7315 // C99 6.5.16.1p1: the left operand is a pointer and the right is
7316 // a null pointer constant.
7317 if ((LHSType->isPointerType() || LHSType->isObjCObjectPointerType() ||
7318 LHSType->isBlockPointerType()) &&
7319 RHS.get()->isNullPointerConstant(Context,
7320 Expr::NPC_ValueDependentIsNull)) {
7321 CastKind Kind;
7322 CXXCastPath Path;
7323 CheckPointerConversion(RHS.get(), LHSType, Kind, Path, false);
7324 if (ConvertRHS)
7325 RHS = ImpCastExprToType(RHS.get(), LHSType, Kind, VK_RValue, &Path);
7326 return Compatible;
7327 }
7328
7329 // This check seems unnatural, however it is necessary to ensure the proper
7330 // conversion of functions/arrays. If the conversion were done for all
7331 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary
7332 // expressions that suppress this implicit conversion (&, sizeof).
7333 //
7334 // Suppress this for references: C++ 8.5.3p5.
7335 if (!LHSType->isReferenceType()) {
7336 // FIXME: We potentially allocate here even if ConvertRHS is false.
7337 RHS = DefaultFunctionArrayLvalueConversion(RHS.get(), Diagnose);
7338 if (RHS.isInvalid())
7339 return Incompatible;
7340 }
7341
7342 Expr *PRE = RHS.get()->IgnoreParenCasts();
7343 if (ObjCProtocolExpr *OPE = dyn_cast<ObjCProtocolExpr>(PRE)) {
7344 ObjCProtocolDecl *PDecl = OPE->getProtocol();
7345 if (PDecl && !PDecl->hasDefinition()) {
7346 Diag(PRE->getExprLoc(), diag::warn_atprotocol_protocol) << PDecl->getName();
7347 Diag(PDecl->getLocation(), diag::note_entity_declared_at) << PDecl;
7348 }
7349 }
7350
7351 CastKind Kind = CK_Invalid;
7352 Sema::AssignConvertType result =
7353 CheckAssignmentConstraints(LHSType, RHS, Kind, ConvertRHS);
7354
7355 // C99 6.5.16.1p2: The value of the right operand is converted to the
7356 // type of the assignment expression.
7357 // CheckAssignmentConstraints allows the left-hand side to be a reference,
7358 // so that we can use references in built-in functions even in C.
7359 // The getNonReferenceType() call makes sure that the resulting expression
7360 // does not have reference type.
7361 if (result != Incompatible && RHS.get()->getType() != LHSType) {
7362 QualType Ty = LHSType.getNonLValueExprType(Context);
7363 Expr *E = RHS.get();
7364 if (getLangOpts().ObjCAutoRefCount)
7365 CheckObjCARCConversion(SourceRange(), Ty, E, CCK_ImplicitConversion,
7366 DiagnoseCFAudited);
7367 if (getLangOpts().ObjC1 &&
7368 (CheckObjCBridgeRelatedConversions(E->getLocStart(),
7369 LHSType, E->getType(), E) ||
7370 ConversionToObjCStringLiteralCheck(LHSType, E))) {
7371 RHS = E;
7372 return Compatible;
7373 }
7374
7375 if (ConvertRHS)
7376 RHS = ImpCastExprToType(E, Ty, Kind);
7377 }
7378 return result;
7379 }
7380
InvalidOperands(SourceLocation Loc,ExprResult & LHS,ExprResult & RHS)7381 QualType Sema::InvalidOperands(SourceLocation Loc, ExprResult &LHS,
7382 ExprResult &RHS) {
7383 Diag(Loc, diag::err_typecheck_invalid_operands)
7384 << LHS.get()->getType() << RHS.get()->getType()
7385 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
7386 return QualType();
7387 }
7388
7389 /// Try to convert a value of non-vector type to a vector type by converting
7390 /// the type to the element type of the vector and then performing a splat.
7391 /// If the language is OpenCL, we only use conversions that promote scalar
7392 /// rank; for C, Obj-C, and C++ we allow any real scalar conversion except
7393 /// for float->int.
7394 ///
7395 /// \param scalar - if non-null, actually perform the conversions
7396 /// \return true if the operation fails (but without diagnosing the failure)
tryVectorConvertAndSplat(Sema & S,ExprResult * scalar,QualType scalarTy,QualType vectorEltTy,QualType vectorTy)7397 static bool tryVectorConvertAndSplat(Sema &S, ExprResult *scalar,
7398 QualType scalarTy,
7399 QualType vectorEltTy,
7400 QualType vectorTy) {
7401 // The conversion to apply to the scalar before splatting it,
7402 // if necessary.
7403 CastKind scalarCast = CK_Invalid;
7404
7405 if (vectorEltTy->isIntegralType(S.Context)) {
7406 if (!scalarTy->isIntegralType(S.Context))
7407 return true;
7408 if (S.getLangOpts().OpenCL &&
7409 S.Context.getIntegerTypeOrder(vectorEltTy, scalarTy) < 0)
7410 return true;
7411 scalarCast = CK_IntegralCast;
7412 } else if (vectorEltTy->isRealFloatingType()) {
7413 if (scalarTy->isRealFloatingType()) {
7414 if (S.getLangOpts().OpenCL &&
7415 S.Context.getFloatingTypeOrder(vectorEltTy, scalarTy) < 0)
7416 return true;
7417 scalarCast = CK_FloatingCast;
7418 }
7419 else if (scalarTy->isIntegralType(S.Context))
7420 scalarCast = CK_IntegralToFloating;
7421 else
7422 return true;
7423 } else {
7424 return true;
7425 }
7426
7427 // Adjust scalar if desired.
7428 if (scalar) {
7429 if (scalarCast != CK_Invalid)
7430 *scalar = S.ImpCastExprToType(scalar->get(), vectorEltTy, scalarCast);
7431 *scalar = S.ImpCastExprToType(scalar->get(), vectorTy, CK_VectorSplat);
7432 }
7433 return false;
7434 }
7435
CheckVectorOperands(ExprResult & LHS,ExprResult & RHS,SourceLocation Loc,bool IsCompAssign,bool AllowBothBool,bool AllowBoolConversions)7436 QualType Sema::CheckVectorOperands(ExprResult &LHS, ExprResult &RHS,
7437 SourceLocation Loc, bool IsCompAssign,
7438 bool AllowBothBool,
7439 bool AllowBoolConversions) {
7440 if (!IsCompAssign) {
7441 LHS = DefaultFunctionArrayLvalueConversion(LHS.get());
7442 if (LHS.isInvalid())
7443 return QualType();
7444 }
7445 RHS = DefaultFunctionArrayLvalueConversion(RHS.get());
7446 if (RHS.isInvalid())
7447 return QualType();
7448
7449 // For conversion purposes, we ignore any qualifiers.
7450 // For example, "const float" and "float" are equivalent.
7451 QualType LHSType = LHS.get()->getType().getUnqualifiedType();
7452 QualType RHSType = RHS.get()->getType().getUnqualifiedType();
7453
7454 const VectorType *LHSVecType = LHSType->getAs<VectorType>();
7455 const VectorType *RHSVecType = RHSType->getAs<VectorType>();
7456 assert(LHSVecType || RHSVecType);
7457
7458 // AltiVec-style "vector bool op vector bool" combinations are allowed
7459 // for some operators but not others.
7460 if (!AllowBothBool &&
7461 LHSVecType && LHSVecType->getVectorKind() == VectorType::AltiVecBool &&
7462 RHSVecType && RHSVecType->getVectorKind() == VectorType::AltiVecBool)
7463 return InvalidOperands(Loc, LHS, RHS);
7464
7465 // If the vector types are identical, return.
7466 if (Context.hasSameType(LHSType, RHSType))
7467 return LHSType;
7468
7469 // If we have compatible AltiVec and GCC vector types, use the AltiVec type.
7470 if (LHSVecType && RHSVecType &&
7471 Context.areCompatibleVectorTypes(LHSType, RHSType)) {
7472 if (isa<ExtVectorType>(LHSVecType)) {
7473 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_BitCast);
7474 return LHSType;
7475 }
7476
7477 if (!IsCompAssign)
7478 LHS = ImpCastExprToType(LHS.get(), RHSType, CK_BitCast);
7479 return RHSType;
7480 }
7481
7482 // AllowBoolConversions says that bool and non-bool AltiVec vectors
7483 // can be mixed, with the result being the non-bool type. The non-bool
7484 // operand must have integer element type.
7485 if (AllowBoolConversions && LHSVecType && RHSVecType &&
7486 LHSVecType->getNumElements() == RHSVecType->getNumElements() &&
7487 (Context.getTypeSize(LHSVecType->getElementType()) ==
7488 Context.getTypeSize(RHSVecType->getElementType()))) {
7489 if (LHSVecType->getVectorKind() == VectorType::AltiVecVector &&
7490 LHSVecType->getElementType()->isIntegerType() &&
7491 RHSVecType->getVectorKind() == VectorType::AltiVecBool) {
7492 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_BitCast);
7493 return LHSType;
7494 }
7495 if (!IsCompAssign &&
7496 LHSVecType->getVectorKind() == VectorType::AltiVecBool &&
7497 RHSVecType->getVectorKind() == VectorType::AltiVecVector &&
7498 RHSVecType->getElementType()->isIntegerType()) {
7499 LHS = ImpCastExprToType(LHS.get(), RHSType, CK_BitCast);
7500 return RHSType;
7501 }
7502 }
7503
7504 // If there's an ext-vector type and a scalar, try to convert the scalar to
7505 // the vector element type and splat.
7506 if (!RHSVecType && isa<ExtVectorType>(LHSVecType)) {
7507 if (!tryVectorConvertAndSplat(*this, &RHS, RHSType,
7508 LHSVecType->getElementType(), LHSType))
7509 return LHSType;
7510 }
7511 if (!LHSVecType && isa<ExtVectorType>(RHSVecType)) {
7512 if (!tryVectorConvertAndSplat(*this, (IsCompAssign ? nullptr : &LHS),
7513 LHSType, RHSVecType->getElementType(),
7514 RHSType))
7515 return RHSType;
7516 }
7517
7518 // If we're allowing lax vector conversions, only the total (data) size
7519 // needs to be the same.
7520 // FIXME: Should we really be allowing this?
7521 // FIXME: We really just pick the LHS type arbitrarily?
7522 if (isLaxVectorConversion(RHSType, LHSType)) {
7523 QualType resultType = LHSType;
7524 RHS = ImpCastExprToType(RHS.get(), resultType, CK_BitCast);
7525 return resultType;
7526 }
7527
7528 // Okay, the expression is invalid.
7529
7530 // If there's a non-vector, non-real operand, diagnose that.
7531 if ((!RHSVecType && !RHSType->isRealType()) ||
7532 (!LHSVecType && !LHSType->isRealType())) {
7533 Diag(Loc, diag::err_typecheck_vector_not_convertable_non_scalar)
7534 << LHSType << RHSType
7535 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
7536 return QualType();
7537 }
7538
7539 // OpenCL V1.1 6.2.6.p1:
7540 // If the operands are of more than one vector type, then an error shall
7541 // occur. Implicit conversions between vector types are not permitted, per
7542 // section 6.2.1.
7543 if (getLangOpts().OpenCL &&
7544 RHSVecType && isa<ExtVectorType>(RHSVecType) &&
7545 LHSVecType && isa<ExtVectorType>(LHSVecType)) {
7546 Diag(Loc, diag::err_opencl_implicit_vector_conversion) << LHSType
7547 << RHSType;
7548 return QualType();
7549 }
7550
7551 // Otherwise, use the generic diagnostic.
7552 Diag(Loc, diag::err_typecheck_vector_not_convertable)
7553 << LHSType << RHSType
7554 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
7555 return QualType();
7556 }
7557
7558 // checkArithmeticNull - Detect when a NULL constant is used improperly in an
7559 // expression. These are mainly cases where the null pointer is used as an
7560 // integer instead of a pointer.
checkArithmeticNull(Sema & S,ExprResult & LHS,ExprResult & RHS,SourceLocation Loc,bool IsCompare)7561 static void checkArithmeticNull(Sema &S, ExprResult &LHS, ExprResult &RHS,
7562 SourceLocation Loc, bool IsCompare) {
7563 // The canonical way to check for a GNU null is with isNullPointerConstant,
7564 // but we use a bit of a hack here for speed; this is a relatively
7565 // hot path, and isNullPointerConstant is slow.
7566 bool LHSNull = isa<GNUNullExpr>(LHS.get()->IgnoreParenImpCasts());
7567 bool RHSNull = isa<GNUNullExpr>(RHS.get()->IgnoreParenImpCasts());
7568
7569 QualType NonNullType = LHSNull ? RHS.get()->getType() : LHS.get()->getType();
7570
7571 // Avoid analyzing cases where the result will either be invalid (and
7572 // diagnosed as such) or entirely valid and not something to warn about.
7573 if ((!LHSNull && !RHSNull) || NonNullType->isBlockPointerType() ||
7574 NonNullType->isMemberPointerType() || NonNullType->isFunctionType())
7575 return;
7576
7577 // Comparison operations would not make sense with a null pointer no matter
7578 // what the other expression is.
7579 if (!IsCompare) {
7580 S.Diag(Loc, diag::warn_null_in_arithmetic_operation)
7581 << (LHSNull ? LHS.get()->getSourceRange() : SourceRange())
7582 << (RHSNull ? RHS.get()->getSourceRange() : SourceRange());
7583 return;
7584 }
7585
7586 // The rest of the operations only make sense with a null pointer
7587 // if the other expression is a pointer.
7588 if (LHSNull == RHSNull || NonNullType->isAnyPointerType() ||
7589 NonNullType->canDecayToPointerType())
7590 return;
7591
7592 S.Diag(Loc, diag::warn_null_in_comparison_operation)
7593 << LHSNull /* LHS is NULL */ << NonNullType
7594 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
7595 }
7596
DiagnoseBadDivideOrRemainderValues(Sema & S,ExprResult & LHS,ExprResult & RHS,SourceLocation Loc,bool IsDiv)7597 static void DiagnoseBadDivideOrRemainderValues(Sema& S, ExprResult &LHS,
7598 ExprResult &RHS,
7599 SourceLocation Loc, bool IsDiv) {
7600 // Check for division/remainder by zero.
7601 llvm::APSInt RHSValue;
7602 if (!RHS.get()->isValueDependent() &&
7603 RHS.get()->EvaluateAsInt(RHSValue, S.Context) && RHSValue == 0)
7604 S.DiagRuntimeBehavior(Loc, RHS.get(),
7605 S.PDiag(diag::warn_remainder_division_by_zero)
7606 << IsDiv << RHS.get()->getSourceRange());
7607 }
7608
CheckMultiplyDivideOperands(ExprResult & LHS,ExprResult & RHS,SourceLocation Loc,bool IsCompAssign,bool IsDiv)7609 QualType Sema::CheckMultiplyDivideOperands(ExprResult &LHS, ExprResult &RHS,
7610 SourceLocation Loc,
7611 bool IsCompAssign, bool IsDiv) {
7612 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
7613
7614 if (LHS.get()->getType()->isVectorType() ||
7615 RHS.get()->getType()->isVectorType())
7616 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign,
7617 /*AllowBothBool*/getLangOpts().AltiVec,
7618 /*AllowBoolConversions*/false);
7619
7620 QualType compType = UsualArithmeticConversions(LHS, RHS, IsCompAssign);
7621 if (LHS.isInvalid() || RHS.isInvalid())
7622 return QualType();
7623
7624
7625 if (compType.isNull() || !compType->isArithmeticType())
7626 return InvalidOperands(Loc, LHS, RHS);
7627 if (IsDiv)
7628 DiagnoseBadDivideOrRemainderValues(*this, LHS, RHS, Loc, IsDiv);
7629 return compType;
7630 }
7631
CheckRemainderOperands(ExprResult & LHS,ExprResult & RHS,SourceLocation Loc,bool IsCompAssign)7632 QualType Sema::CheckRemainderOperands(
7633 ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, bool IsCompAssign) {
7634 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
7635
7636 if (LHS.get()->getType()->isVectorType() ||
7637 RHS.get()->getType()->isVectorType()) {
7638 if (LHS.get()->getType()->hasIntegerRepresentation() &&
7639 RHS.get()->getType()->hasIntegerRepresentation())
7640 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign,
7641 /*AllowBothBool*/getLangOpts().AltiVec,
7642 /*AllowBoolConversions*/false);
7643 return InvalidOperands(Loc, LHS, RHS);
7644 }
7645
7646 QualType compType = UsualArithmeticConversions(LHS, RHS, IsCompAssign);
7647 if (LHS.isInvalid() || RHS.isInvalid())
7648 return QualType();
7649
7650 if (compType.isNull() || !compType->isIntegerType())
7651 return InvalidOperands(Loc, LHS, RHS);
7652 DiagnoseBadDivideOrRemainderValues(*this, LHS, RHS, Loc, false /* IsDiv */);
7653 return compType;
7654 }
7655
7656 /// \brief Diagnose invalid arithmetic on two void pointers.
diagnoseArithmeticOnTwoVoidPointers(Sema & S,SourceLocation Loc,Expr * LHSExpr,Expr * RHSExpr)7657 static void diagnoseArithmeticOnTwoVoidPointers(Sema &S, SourceLocation Loc,
7658 Expr *LHSExpr, Expr *RHSExpr) {
7659 S.Diag(Loc, S.getLangOpts().CPlusPlus
7660 ? diag::err_typecheck_pointer_arith_void_type
7661 : diag::ext_gnu_void_ptr)
7662 << 1 /* two pointers */ << LHSExpr->getSourceRange()
7663 << RHSExpr->getSourceRange();
7664 }
7665
7666 /// \brief Diagnose invalid arithmetic on a void pointer.
diagnoseArithmeticOnVoidPointer(Sema & S,SourceLocation Loc,Expr * Pointer)7667 static void diagnoseArithmeticOnVoidPointer(Sema &S, SourceLocation Loc,
7668 Expr *Pointer) {
7669 S.Diag(Loc, S.getLangOpts().CPlusPlus
7670 ? diag::err_typecheck_pointer_arith_void_type
7671 : diag::ext_gnu_void_ptr)
7672 << 0 /* one pointer */ << Pointer->getSourceRange();
7673 }
7674
7675 /// \brief Diagnose invalid arithmetic on two function pointers.
diagnoseArithmeticOnTwoFunctionPointers(Sema & S,SourceLocation Loc,Expr * LHS,Expr * RHS)7676 static void diagnoseArithmeticOnTwoFunctionPointers(Sema &S, SourceLocation Loc,
7677 Expr *LHS, Expr *RHS) {
7678 assert(LHS->getType()->isAnyPointerType());
7679 assert(RHS->getType()->isAnyPointerType());
7680 S.Diag(Loc, S.getLangOpts().CPlusPlus
7681 ? diag::err_typecheck_pointer_arith_function_type
7682 : diag::ext_gnu_ptr_func_arith)
7683 << 1 /* two pointers */ << LHS->getType()->getPointeeType()
7684 // We only show the second type if it differs from the first.
7685 << (unsigned)!S.Context.hasSameUnqualifiedType(LHS->getType(),
7686 RHS->getType())
7687 << RHS->getType()->getPointeeType()
7688 << LHS->getSourceRange() << RHS->getSourceRange();
7689 }
7690
7691 /// \brief Diagnose invalid arithmetic on a function pointer.
diagnoseArithmeticOnFunctionPointer(Sema & S,SourceLocation Loc,Expr * Pointer)7692 static void diagnoseArithmeticOnFunctionPointer(Sema &S, SourceLocation Loc,
7693 Expr *Pointer) {
7694 assert(Pointer->getType()->isAnyPointerType());
7695 S.Diag(Loc, S.getLangOpts().CPlusPlus
7696 ? diag::err_typecheck_pointer_arith_function_type
7697 : diag::ext_gnu_ptr_func_arith)
7698 << 0 /* one pointer */ << Pointer->getType()->getPointeeType()
7699 << 0 /* one pointer, so only one type */
7700 << Pointer->getSourceRange();
7701 }
7702
7703 /// \brief Emit error if Operand is incomplete pointer type
7704 ///
7705 /// \returns True if pointer has incomplete type
checkArithmeticIncompletePointerType(Sema & S,SourceLocation Loc,Expr * Operand)7706 static bool checkArithmeticIncompletePointerType(Sema &S, SourceLocation Loc,
7707 Expr *Operand) {
7708 QualType ResType = Operand->getType();
7709 if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>())
7710 ResType = ResAtomicType->getValueType();
7711
7712 assert(ResType->isAnyPointerType() && !ResType->isDependentType());
7713 QualType PointeeTy = ResType->getPointeeType();
7714 return S.RequireCompleteType(Loc, PointeeTy,
7715 diag::err_typecheck_arithmetic_incomplete_type,
7716 PointeeTy, Operand->getSourceRange());
7717 }
7718
7719 /// \brief Check the validity of an arithmetic pointer operand.
7720 ///
7721 /// If the operand has pointer type, this code will check for pointer types
7722 /// which are invalid in arithmetic operations. These will be diagnosed
7723 /// appropriately, including whether or not the use is supported as an
7724 /// extension.
7725 ///
7726 /// \returns True when the operand is valid to use (even if as an extension).
checkArithmeticOpPointerOperand(Sema & S,SourceLocation Loc,Expr * Operand)7727 static bool checkArithmeticOpPointerOperand(Sema &S, SourceLocation Loc,
7728 Expr *Operand) {
7729 QualType ResType = Operand->getType();
7730 if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>())
7731 ResType = ResAtomicType->getValueType();
7732
7733 if (!ResType->isAnyPointerType()) return true;
7734
7735 QualType PointeeTy = ResType->getPointeeType();
7736 if (PointeeTy->isVoidType()) {
7737 diagnoseArithmeticOnVoidPointer(S, Loc, Operand);
7738 return !S.getLangOpts().CPlusPlus;
7739 }
7740 if (PointeeTy->isFunctionType()) {
7741 diagnoseArithmeticOnFunctionPointer(S, Loc, Operand);
7742 return !S.getLangOpts().CPlusPlus;
7743 }
7744
7745 if (checkArithmeticIncompletePointerType(S, Loc, Operand)) return false;
7746
7747 return true;
7748 }
7749
7750 /// \brief Check the validity of a binary arithmetic operation w.r.t. pointer
7751 /// operands.
7752 ///
7753 /// This routine will diagnose any invalid arithmetic on pointer operands much
7754 /// like \see checkArithmeticOpPointerOperand. However, it has special logic
7755 /// for emitting a single diagnostic even for operations where both LHS and RHS
7756 /// are (potentially problematic) pointers.
7757 ///
7758 /// \returns True when the operand is valid to use (even if as an extension).
checkArithmeticBinOpPointerOperands(Sema & S,SourceLocation Loc,Expr * LHSExpr,Expr * RHSExpr)7759 static bool checkArithmeticBinOpPointerOperands(Sema &S, SourceLocation Loc,
7760 Expr *LHSExpr, Expr *RHSExpr) {
7761 bool isLHSPointer = LHSExpr->getType()->isAnyPointerType();
7762 bool isRHSPointer = RHSExpr->getType()->isAnyPointerType();
7763 if (!isLHSPointer && !isRHSPointer) return true;
7764
7765 QualType LHSPointeeTy, RHSPointeeTy;
7766 if (isLHSPointer) LHSPointeeTy = LHSExpr->getType()->getPointeeType();
7767 if (isRHSPointer) RHSPointeeTy = RHSExpr->getType()->getPointeeType();
7768
7769 // if both are pointers check if operation is valid wrt address spaces
7770 if (S.getLangOpts().OpenCL && isLHSPointer && isRHSPointer) {
7771 const PointerType *lhsPtr = LHSExpr->getType()->getAs<PointerType>();
7772 const PointerType *rhsPtr = RHSExpr->getType()->getAs<PointerType>();
7773 if (!lhsPtr->isAddressSpaceOverlapping(*rhsPtr)) {
7774 S.Diag(Loc,
7775 diag::err_typecheck_op_on_nonoverlapping_address_space_pointers)
7776 << LHSExpr->getType() << RHSExpr->getType() << 1 /*arithmetic op*/
7777 << LHSExpr->getSourceRange() << RHSExpr->getSourceRange();
7778 return false;
7779 }
7780 }
7781
7782 // Check for arithmetic on pointers to incomplete types.
7783 bool isLHSVoidPtr = isLHSPointer && LHSPointeeTy->isVoidType();
7784 bool isRHSVoidPtr = isRHSPointer && RHSPointeeTy->isVoidType();
7785 if (isLHSVoidPtr || isRHSVoidPtr) {
7786 if (!isRHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, LHSExpr);
7787 else if (!isLHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, RHSExpr);
7788 else diagnoseArithmeticOnTwoVoidPointers(S, Loc, LHSExpr, RHSExpr);
7789
7790 return !S.getLangOpts().CPlusPlus;
7791 }
7792
7793 bool isLHSFuncPtr = isLHSPointer && LHSPointeeTy->isFunctionType();
7794 bool isRHSFuncPtr = isRHSPointer && RHSPointeeTy->isFunctionType();
7795 if (isLHSFuncPtr || isRHSFuncPtr) {
7796 if (!isRHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc, LHSExpr);
7797 else if (!isLHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc,
7798 RHSExpr);
7799 else diagnoseArithmeticOnTwoFunctionPointers(S, Loc, LHSExpr, RHSExpr);
7800
7801 return !S.getLangOpts().CPlusPlus;
7802 }
7803
7804 if (isLHSPointer && checkArithmeticIncompletePointerType(S, Loc, LHSExpr))
7805 return false;
7806 if (isRHSPointer && checkArithmeticIncompletePointerType(S, Loc, RHSExpr))
7807 return false;
7808
7809 return true;
7810 }
7811
7812 /// diagnoseStringPlusInt - Emit a warning when adding an integer to a string
7813 /// literal.
diagnoseStringPlusInt(Sema & Self,SourceLocation OpLoc,Expr * LHSExpr,Expr * RHSExpr)7814 static void diagnoseStringPlusInt(Sema &Self, SourceLocation OpLoc,
7815 Expr *LHSExpr, Expr *RHSExpr) {
7816 StringLiteral* StrExpr = dyn_cast<StringLiteral>(LHSExpr->IgnoreImpCasts());
7817 Expr* IndexExpr = RHSExpr;
7818 if (!StrExpr) {
7819 StrExpr = dyn_cast<StringLiteral>(RHSExpr->IgnoreImpCasts());
7820 IndexExpr = LHSExpr;
7821 }
7822
7823 bool IsStringPlusInt = StrExpr &&
7824 IndexExpr->getType()->isIntegralOrUnscopedEnumerationType();
7825 if (!IsStringPlusInt || IndexExpr->isValueDependent())
7826 return;
7827
7828 llvm::APSInt index;
7829 if (IndexExpr->EvaluateAsInt(index, Self.getASTContext())) {
7830 unsigned StrLenWithNull = StrExpr->getLength() + 1;
7831 if (index.isNonNegative() &&
7832 index <= llvm::APSInt(llvm::APInt(index.getBitWidth(), StrLenWithNull),
7833 index.isUnsigned()))
7834 return;
7835 }
7836
7837 SourceRange DiagRange(LHSExpr->getLocStart(), RHSExpr->getLocEnd());
7838 Self.Diag(OpLoc, diag::warn_string_plus_int)
7839 << DiagRange << IndexExpr->IgnoreImpCasts()->getType();
7840
7841 // Only print a fixit for "str" + int, not for int + "str".
7842 if (IndexExpr == RHSExpr) {
7843 SourceLocation EndLoc = Self.getLocForEndOfToken(RHSExpr->getLocEnd());
7844 Self.Diag(OpLoc, diag::note_string_plus_scalar_silence)
7845 << FixItHint::CreateInsertion(LHSExpr->getLocStart(), "&")
7846 << FixItHint::CreateReplacement(SourceRange(OpLoc), "[")
7847 << FixItHint::CreateInsertion(EndLoc, "]");
7848 } else
7849 Self.Diag(OpLoc, diag::note_string_plus_scalar_silence);
7850 }
7851
7852 /// \brief Emit a warning when adding a char literal to a string.
diagnoseStringPlusChar(Sema & Self,SourceLocation OpLoc,Expr * LHSExpr,Expr * RHSExpr)7853 static void diagnoseStringPlusChar(Sema &Self, SourceLocation OpLoc,
7854 Expr *LHSExpr, Expr *RHSExpr) {
7855 const Expr *StringRefExpr = LHSExpr;
7856 const CharacterLiteral *CharExpr =
7857 dyn_cast<CharacterLiteral>(RHSExpr->IgnoreImpCasts());
7858
7859 if (!CharExpr) {
7860 CharExpr = dyn_cast<CharacterLiteral>(LHSExpr->IgnoreImpCasts());
7861 StringRefExpr = RHSExpr;
7862 }
7863
7864 if (!CharExpr || !StringRefExpr)
7865 return;
7866
7867 const QualType StringType = StringRefExpr->getType();
7868
7869 // Return if not a PointerType.
7870 if (!StringType->isAnyPointerType())
7871 return;
7872
7873 // Return if not a CharacterType.
7874 if (!StringType->getPointeeType()->isAnyCharacterType())
7875 return;
7876
7877 ASTContext &Ctx = Self.getASTContext();
7878 SourceRange DiagRange(LHSExpr->getLocStart(), RHSExpr->getLocEnd());
7879
7880 const QualType CharType = CharExpr->getType();
7881 if (!CharType->isAnyCharacterType() &&
7882 CharType->isIntegerType() &&
7883 llvm::isUIntN(Ctx.getCharWidth(), CharExpr->getValue())) {
7884 Self.Diag(OpLoc, diag::warn_string_plus_char)
7885 << DiagRange << Ctx.CharTy;
7886 } else {
7887 Self.Diag(OpLoc, diag::warn_string_plus_char)
7888 << DiagRange << CharExpr->getType();
7889 }
7890
7891 // Only print a fixit for str + char, not for char + str.
7892 if (isa<CharacterLiteral>(RHSExpr->IgnoreImpCasts())) {
7893 SourceLocation EndLoc = Self.getLocForEndOfToken(RHSExpr->getLocEnd());
7894 Self.Diag(OpLoc, diag::note_string_plus_scalar_silence)
7895 << FixItHint::CreateInsertion(LHSExpr->getLocStart(), "&")
7896 << FixItHint::CreateReplacement(SourceRange(OpLoc), "[")
7897 << FixItHint::CreateInsertion(EndLoc, "]");
7898 } else {
7899 Self.Diag(OpLoc, diag::note_string_plus_scalar_silence);
7900 }
7901 }
7902
7903 /// \brief Emit error when two pointers are incompatible.
diagnosePointerIncompatibility(Sema & S,SourceLocation Loc,Expr * LHSExpr,Expr * RHSExpr)7904 static void diagnosePointerIncompatibility(Sema &S, SourceLocation Loc,
7905 Expr *LHSExpr, Expr *RHSExpr) {
7906 assert(LHSExpr->getType()->isAnyPointerType());
7907 assert(RHSExpr->getType()->isAnyPointerType());
7908 S.Diag(Loc, diag::err_typecheck_sub_ptr_compatible)
7909 << LHSExpr->getType() << RHSExpr->getType() << LHSExpr->getSourceRange()
7910 << RHSExpr->getSourceRange();
7911 }
7912
7913 // C99 6.5.6
CheckAdditionOperands(ExprResult & LHS,ExprResult & RHS,SourceLocation Loc,BinaryOperatorKind Opc,QualType * CompLHSTy)7914 QualType Sema::CheckAdditionOperands(ExprResult &LHS, ExprResult &RHS,
7915 SourceLocation Loc, BinaryOperatorKind Opc,
7916 QualType* CompLHSTy) {
7917 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
7918
7919 if (LHS.get()->getType()->isVectorType() ||
7920 RHS.get()->getType()->isVectorType()) {
7921 QualType compType = CheckVectorOperands(
7922 LHS, RHS, Loc, CompLHSTy,
7923 /*AllowBothBool*/getLangOpts().AltiVec,
7924 /*AllowBoolConversions*/getLangOpts().ZVector);
7925 if (CompLHSTy) *CompLHSTy = compType;
7926 return compType;
7927 }
7928
7929 QualType compType = UsualArithmeticConversions(LHS, RHS, CompLHSTy);
7930 if (LHS.isInvalid() || RHS.isInvalid())
7931 return QualType();
7932
7933 // Diagnose "string literal" '+' int and string '+' "char literal".
7934 if (Opc == BO_Add) {
7935 diagnoseStringPlusInt(*this, Loc, LHS.get(), RHS.get());
7936 diagnoseStringPlusChar(*this, Loc, LHS.get(), RHS.get());
7937 }
7938
7939 // handle the common case first (both operands are arithmetic).
7940 if (!compType.isNull() && compType->isArithmeticType()) {
7941 if (CompLHSTy) *CompLHSTy = compType;
7942 return compType;
7943 }
7944
7945 // Type-checking. Ultimately the pointer's going to be in PExp;
7946 // note that we bias towards the LHS being the pointer.
7947 Expr *PExp = LHS.get(), *IExp = RHS.get();
7948
7949 bool isObjCPointer;
7950 if (PExp->getType()->isPointerType()) {
7951 isObjCPointer = false;
7952 } else if (PExp->getType()->isObjCObjectPointerType()) {
7953 isObjCPointer = true;
7954 } else {
7955 std::swap(PExp, IExp);
7956 if (PExp->getType()->isPointerType()) {
7957 isObjCPointer = false;
7958 } else if (PExp->getType()->isObjCObjectPointerType()) {
7959 isObjCPointer = true;
7960 } else {
7961 return InvalidOperands(Loc, LHS, RHS);
7962 }
7963 }
7964 assert(PExp->getType()->isAnyPointerType());
7965
7966 if (!IExp->getType()->isIntegerType())
7967 return InvalidOperands(Loc, LHS, RHS);
7968
7969 if (!checkArithmeticOpPointerOperand(*this, Loc, PExp))
7970 return QualType();
7971
7972 if (isObjCPointer && checkArithmeticOnObjCPointer(*this, Loc, PExp))
7973 return QualType();
7974
7975 // Check array bounds for pointer arithemtic
7976 CheckArrayAccess(PExp, IExp);
7977
7978 if (CompLHSTy) {
7979 QualType LHSTy = Context.isPromotableBitField(LHS.get());
7980 if (LHSTy.isNull()) {
7981 LHSTy = LHS.get()->getType();
7982 if (LHSTy->isPromotableIntegerType())
7983 LHSTy = Context.getPromotedIntegerType(LHSTy);
7984 }
7985 *CompLHSTy = LHSTy;
7986 }
7987
7988 return PExp->getType();
7989 }
7990
7991 // C99 6.5.6
CheckSubtractionOperands(ExprResult & LHS,ExprResult & RHS,SourceLocation Loc,QualType * CompLHSTy)7992 QualType Sema::CheckSubtractionOperands(ExprResult &LHS, ExprResult &RHS,
7993 SourceLocation Loc,
7994 QualType* CompLHSTy) {
7995 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
7996
7997 if (LHS.get()->getType()->isVectorType() ||
7998 RHS.get()->getType()->isVectorType()) {
7999 QualType compType = CheckVectorOperands(
8000 LHS, RHS, Loc, CompLHSTy,
8001 /*AllowBothBool*/getLangOpts().AltiVec,
8002 /*AllowBoolConversions*/getLangOpts().ZVector);
8003 if (CompLHSTy) *CompLHSTy = compType;
8004 return compType;
8005 }
8006
8007 QualType compType = UsualArithmeticConversions(LHS, RHS, CompLHSTy);
8008 if (LHS.isInvalid() || RHS.isInvalid())
8009 return QualType();
8010
8011 // Enforce type constraints: C99 6.5.6p3.
8012
8013 // Handle the common case first (both operands are arithmetic).
8014 if (!compType.isNull() && compType->isArithmeticType()) {
8015 if (CompLHSTy) *CompLHSTy = compType;
8016 return compType;
8017 }
8018
8019 // Either ptr - int or ptr - ptr.
8020 if (LHS.get()->getType()->isAnyPointerType()) {
8021 QualType lpointee = LHS.get()->getType()->getPointeeType();
8022
8023 // Diagnose bad cases where we step over interface counts.
8024 if (LHS.get()->getType()->isObjCObjectPointerType() &&
8025 checkArithmeticOnObjCPointer(*this, Loc, LHS.get()))
8026 return QualType();
8027
8028 // The result type of a pointer-int computation is the pointer type.
8029 if (RHS.get()->getType()->isIntegerType()) {
8030 if (!checkArithmeticOpPointerOperand(*this, Loc, LHS.get()))
8031 return QualType();
8032
8033 // Check array bounds for pointer arithemtic
8034 CheckArrayAccess(LHS.get(), RHS.get(), /*ArraySubscriptExpr*/nullptr,
8035 /*AllowOnePastEnd*/true, /*IndexNegated*/true);
8036
8037 if (CompLHSTy) *CompLHSTy = LHS.get()->getType();
8038 return LHS.get()->getType();
8039 }
8040
8041 // Handle pointer-pointer subtractions.
8042 if (const PointerType *RHSPTy
8043 = RHS.get()->getType()->getAs<PointerType>()) {
8044 QualType rpointee = RHSPTy->getPointeeType();
8045
8046 if (getLangOpts().CPlusPlus) {
8047 // Pointee types must be the same: C++ [expr.add]
8048 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) {
8049 diagnosePointerIncompatibility(*this, Loc, LHS.get(), RHS.get());
8050 }
8051 } else {
8052 // Pointee types must be compatible C99 6.5.6p3
8053 if (!Context.typesAreCompatible(
8054 Context.getCanonicalType(lpointee).getUnqualifiedType(),
8055 Context.getCanonicalType(rpointee).getUnqualifiedType())) {
8056 diagnosePointerIncompatibility(*this, Loc, LHS.get(), RHS.get());
8057 return QualType();
8058 }
8059 }
8060
8061 if (!checkArithmeticBinOpPointerOperands(*this, Loc,
8062 LHS.get(), RHS.get()))
8063 return QualType();
8064
8065 // The pointee type may have zero size. As an extension, a structure or
8066 // union may have zero size or an array may have zero length. In this
8067 // case subtraction does not make sense.
8068 if (!rpointee->isVoidType() && !rpointee->isFunctionType()) {
8069 CharUnits ElementSize = Context.getTypeSizeInChars(rpointee);
8070 if (ElementSize.isZero()) {
8071 Diag(Loc,diag::warn_sub_ptr_zero_size_types)
8072 << rpointee.getUnqualifiedType()
8073 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
8074 }
8075 }
8076
8077 if (CompLHSTy) *CompLHSTy = LHS.get()->getType();
8078 return Context.getPointerDiffType();
8079 }
8080 }
8081
8082 return InvalidOperands(Loc, LHS, RHS);
8083 }
8084
isScopedEnumerationType(QualType T)8085 static bool isScopedEnumerationType(QualType T) {
8086 if (const EnumType *ET = T->getAs<EnumType>())
8087 return ET->getDecl()->isScoped();
8088 return false;
8089 }
8090
DiagnoseBadShiftValues(Sema & S,ExprResult & LHS,ExprResult & RHS,SourceLocation Loc,BinaryOperatorKind Opc,QualType LHSType)8091 static void DiagnoseBadShiftValues(Sema& S, ExprResult &LHS, ExprResult &RHS,
8092 SourceLocation Loc, BinaryOperatorKind Opc,
8093 QualType LHSType) {
8094 // OpenCL 6.3j: shift values are effectively % word size of LHS (more defined),
8095 // so skip remaining warnings as we don't want to modify values within Sema.
8096 if (S.getLangOpts().OpenCL)
8097 return;
8098
8099 llvm::APSInt Right;
8100 // Check right/shifter operand
8101 if (RHS.get()->isValueDependent() ||
8102 !RHS.get()->EvaluateAsInt(Right, S.Context))
8103 return;
8104
8105 if (Right.isNegative()) {
8106 S.DiagRuntimeBehavior(Loc, RHS.get(),
8107 S.PDiag(diag::warn_shift_negative)
8108 << RHS.get()->getSourceRange());
8109 return;
8110 }
8111 llvm::APInt LeftBits(Right.getBitWidth(),
8112 S.Context.getTypeSize(LHS.get()->getType()));
8113 if (Right.uge(LeftBits)) {
8114 S.DiagRuntimeBehavior(Loc, RHS.get(),
8115 S.PDiag(diag::warn_shift_gt_typewidth)
8116 << RHS.get()->getSourceRange());
8117 return;
8118 }
8119 if (Opc != BO_Shl)
8120 return;
8121
8122 // When left shifting an ICE which is signed, we can check for overflow which
8123 // according to C++ has undefined behavior ([expr.shift] 5.8/2). Unsigned
8124 // integers have defined behavior modulo one more than the maximum value
8125 // representable in the result type, so never warn for those.
8126 llvm::APSInt Left;
8127 if (LHS.get()->isValueDependent() ||
8128 LHSType->hasUnsignedIntegerRepresentation() ||
8129 !LHS.get()->EvaluateAsInt(Left, S.Context))
8130 return;
8131
8132 // If LHS does not have a signed type and non-negative value
8133 // then, the behavior is undefined. Warn about it.
8134 if (Left.isNegative()) {
8135 S.DiagRuntimeBehavior(Loc, LHS.get(),
8136 S.PDiag(diag::warn_shift_lhs_negative)
8137 << LHS.get()->getSourceRange());
8138 return;
8139 }
8140
8141 llvm::APInt ResultBits =
8142 static_cast<llvm::APInt&>(Right) + Left.getMinSignedBits();
8143 if (LeftBits.uge(ResultBits))
8144 return;
8145 llvm::APSInt Result = Left.extend(ResultBits.getLimitedValue());
8146 Result = Result.shl(Right);
8147
8148 // Print the bit representation of the signed integer as an unsigned
8149 // hexadecimal number.
8150 SmallString<40> HexResult;
8151 Result.toString(HexResult, 16, /*Signed =*/false, /*Literal =*/true);
8152
8153 // If we are only missing a sign bit, this is less likely to result in actual
8154 // bugs -- if the result is cast back to an unsigned type, it will have the
8155 // expected value. Thus we place this behind a different warning that can be
8156 // turned off separately if needed.
8157 if (LeftBits == ResultBits - 1) {
8158 S.Diag(Loc, diag::warn_shift_result_sets_sign_bit)
8159 << HexResult << LHSType
8160 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
8161 return;
8162 }
8163
8164 S.Diag(Loc, diag::warn_shift_result_gt_typewidth)
8165 << HexResult.str() << Result.getMinSignedBits() << LHSType
8166 << Left.getBitWidth() << LHS.get()->getSourceRange()
8167 << RHS.get()->getSourceRange();
8168 }
8169
8170 /// \brief Return the resulting type when an OpenCL vector is shifted
8171 /// by a scalar or vector shift amount.
checkOpenCLVectorShift(Sema & S,ExprResult & LHS,ExprResult & RHS,SourceLocation Loc,bool IsCompAssign)8172 static QualType checkOpenCLVectorShift(Sema &S,
8173 ExprResult &LHS, ExprResult &RHS,
8174 SourceLocation Loc, bool IsCompAssign) {
8175 // OpenCL v1.1 s6.3.j says RHS can be a vector only if LHS is a vector.
8176 if (!LHS.get()->getType()->isVectorType()) {
8177 S.Diag(Loc, diag::err_shift_rhs_only_vector)
8178 << RHS.get()->getType() << LHS.get()->getType()
8179 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
8180 return QualType();
8181 }
8182
8183 if (!IsCompAssign) {
8184 LHS = S.UsualUnaryConversions(LHS.get());
8185 if (LHS.isInvalid()) return QualType();
8186 }
8187
8188 RHS = S.UsualUnaryConversions(RHS.get());
8189 if (RHS.isInvalid()) return QualType();
8190
8191 QualType LHSType = LHS.get()->getType();
8192 const VectorType *LHSVecTy = LHSType->getAs<VectorType>();
8193 QualType LHSEleType = LHSVecTy->getElementType();
8194
8195 // Note that RHS might not be a vector.
8196 QualType RHSType = RHS.get()->getType();
8197 const VectorType *RHSVecTy = RHSType->getAs<VectorType>();
8198 QualType RHSEleType = RHSVecTy ? RHSVecTy->getElementType() : RHSType;
8199
8200 // OpenCL v1.1 s6.3.j says that the operands need to be integers.
8201 if (!LHSEleType->isIntegerType()) {
8202 S.Diag(Loc, diag::err_typecheck_expect_int)
8203 << LHS.get()->getType() << LHS.get()->getSourceRange();
8204 return QualType();
8205 }
8206
8207 if (!RHSEleType->isIntegerType()) {
8208 S.Diag(Loc, diag::err_typecheck_expect_int)
8209 << RHS.get()->getType() << RHS.get()->getSourceRange();
8210 return QualType();
8211 }
8212
8213 if (RHSVecTy) {
8214 // OpenCL v1.1 s6.3.j says that for vector types, the operators
8215 // are applied component-wise. So if RHS is a vector, then ensure
8216 // that the number of elements is the same as LHS...
8217 if (RHSVecTy->getNumElements() != LHSVecTy->getNumElements()) {
8218 S.Diag(Loc, diag::err_typecheck_vector_lengths_not_equal)
8219 << LHS.get()->getType() << RHS.get()->getType()
8220 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
8221 return QualType();
8222 }
8223 } else {
8224 // ...else expand RHS to match the number of elements in LHS.
8225 QualType VecTy =
8226 S.Context.getExtVectorType(RHSEleType, LHSVecTy->getNumElements());
8227 RHS = S.ImpCastExprToType(RHS.get(), VecTy, CK_VectorSplat);
8228 }
8229
8230 return LHSType;
8231 }
8232
8233 // C99 6.5.7
CheckShiftOperands(ExprResult & LHS,ExprResult & RHS,SourceLocation Loc,BinaryOperatorKind Opc,bool IsCompAssign)8234 QualType Sema::CheckShiftOperands(ExprResult &LHS, ExprResult &RHS,
8235 SourceLocation Loc, BinaryOperatorKind Opc,
8236 bool IsCompAssign) {
8237 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
8238
8239 // Vector shifts promote their scalar inputs to vector type.
8240 if (LHS.get()->getType()->isVectorType() ||
8241 RHS.get()->getType()->isVectorType()) {
8242 if (LangOpts.OpenCL)
8243 return checkOpenCLVectorShift(*this, LHS, RHS, Loc, IsCompAssign);
8244 if (LangOpts.ZVector) {
8245 // The shift operators for the z vector extensions work basically
8246 // like OpenCL shifts, except that neither the LHS nor the RHS is
8247 // allowed to be a "vector bool".
8248 if (auto LHSVecType = LHS.get()->getType()->getAs<VectorType>())
8249 if (LHSVecType->getVectorKind() == VectorType::AltiVecBool)
8250 return InvalidOperands(Loc, LHS, RHS);
8251 if (auto RHSVecType = RHS.get()->getType()->getAs<VectorType>())
8252 if (RHSVecType->getVectorKind() == VectorType::AltiVecBool)
8253 return InvalidOperands(Loc, LHS, RHS);
8254 return checkOpenCLVectorShift(*this, LHS, RHS, Loc, IsCompAssign);
8255 }
8256 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign,
8257 /*AllowBothBool*/true,
8258 /*AllowBoolConversions*/false);
8259 }
8260
8261 // Shifts don't perform usual arithmetic conversions, they just do integer
8262 // promotions on each operand. C99 6.5.7p3
8263
8264 // For the LHS, do usual unary conversions, but then reset them away
8265 // if this is a compound assignment.
8266 ExprResult OldLHS = LHS;
8267 LHS = UsualUnaryConversions(LHS.get());
8268 if (LHS.isInvalid())
8269 return QualType();
8270 QualType LHSType = LHS.get()->getType();
8271 if (IsCompAssign) LHS = OldLHS;
8272
8273 // The RHS is simpler.
8274 RHS = UsualUnaryConversions(RHS.get());
8275 if (RHS.isInvalid())
8276 return QualType();
8277 QualType RHSType = RHS.get()->getType();
8278
8279 // C99 6.5.7p2: Each of the operands shall have integer type.
8280 if (!LHSType->hasIntegerRepresentation() ||
8281 !RHSType->hasIntegerRepresentation())
8282 return InvalidOperands(Loc, LHS, RHS);
8283
8284 // C++0x: Don't allow scoped enums. FIXME: Use something better than
8285 // hasIntegerRepresentation() above instead of this.
8286 if (isScopedEnumerationType(LHSType) ||
8287 isScopedEnumerationType(RHSType)) {
8288 return InvalidOperands(Loc, LHS, RHS);
8289 }
8290 // Sanity-check shift operands
8291 DiagnoseBadShiftValues(*this, LHS, RHS, Loc, Opc, LHSType);
8292
8293 // "The type of the result is that of the promoted left operand."
8294 return LHSType;
8295 }
8296
IsWithinTemplateSpecialization(Decl * D)8297 static bool IsWithinTemplateSpecialization(Decl *D) {
8298 if (DeclContext *DC = D->getDeclContext()) {
8299 if (isa<ClassTemplateSpecializationDecl>(DC))
8300 return true;
8301 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DC))
8302 return FD->isFunctionTemplateSpecialization();
8303 }
8304 return false;
8305 }
8306
8307 /// If two different enums are compared, raise a warning.
checkEnumComparison(Sema & S,SourceLocation Loc,Expr * LHS,Expr * RHS)8308 static void checkEnumComparison(Sema &S, SourceLocation Loc, Expr *LHS,
8309 Expr *RHS) {
8310 QualType LHSStrippedType = LHS->IgnoreParenImpCasts()->getType();
8311 QualType RHSStrippedType = RHS->IgnoreParenImpCasts()->getType();
8312
8313 const EnumType *LHSEnumType = LHSStrippedType->getAs<EnumType>();
8314 if (!LHSEnumType)
8315 return;
8316 const EnumType *RHSEnumType = RHSStrippedType->getAs<EnumType>();
8317 if (!RHSEnumType)
8318 return;
8319
8320 // Ignore anonymous enums.
8321 if (!LHSEnumType->getDecl()->getIdentifier())
8322 return;
8323 if (!RHSEnumType->getDecl()->getIdentifier())
8324 return;
8325
8326 if (S.Context.hasSameUnqualifiedType(LHSStrippedType, RHSStrippedType))
8327 return;
8328
8329 S.Diag(Loc, diag::warn_comparison_of_mixed_enum_types)
8330 << LHSStrippedType << RHSStrippedType
8331 << LHS->getSourceRange() << RHS->getSourceRange();
8332 }
8333
8334 /// \brief Diagnose bad pointer comparisons.
diagnoseDistinctPointerComparison(Sema & S,SourceLocation Loc,ExprResult & LHS,ExprResult & RHS,bool IsError)8335 static void diagnoseDistinctPointerComparison(Sema &S, SourceLocation Loc,
8336 ExprResult &LHS, ExprResult &RHS,
8337 bool IsError) {
8338 S.Diag(Loc, IsError ? diag::err_typecheck_comparison_of_distinct_pointers
8339 : diag::ext_typecheck_comparison_of_distinct_pointers)
8340 << LHS.get()->getType() << RHS.get()->getType()
8341 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
8342 }
8343
8344 /// \brief Returns false if the pointers are converted to a composite type,
8345 /// true otherwise.
convertPointersToCompositeType(Sema & S,SourceLocation Loc,ExprResult & LHS,ExprResult & RHS)8346 static bool convertPointersToCompositeType(Sema &S, SourceLocation Loc,
8347 ExprResult &LHS, ExprResult &RHS) {
8348 // C++ [expr.rel]p2:
8349 // [...] Pointer conversions (4.10) and qualification
8350 // conversions (4.4) are performed on pointer operands (or on
8351 // a pointer operand and a null pointer constant) to bring
8352 // them to their composite pointer type. [...]
8353 //
8354 // C++ [expr.eq]p1 uses the same notion for (in)equality
8355 // comparisons of pointers.
8356
8357 // C++ [expr.eq]p2:
8358 // In addition, pointers to members can be compared, or a pointer to
8359 // member and a null pointer constant. Pointer to member conversions
8360 // (4.11) and qualification conversions (4.4) are performed to bring
8361 // them to a common type. If one operand is a null pointer constant,
8362 // the common type is the type of the other operand. Otherwise, the
8363 // common type is a pointer to member type similar (4.4) to the type
8364 // of one of the operands, with a cv-qualification signature (4.4)
8365 // that is the union of the cv-qualification signatures of the operand
8366 // types.
8367
8368 QualType LHSType = LHS.get()->getType();
8369 QualType RHSType = RHS.get()->getType();
8370 assert((LHSType->isPointerType() && RHSType->isPointerType()) ||
8371 (LHSType->isMemberPointerType() && RHSType->isMemberPointerType()));
8372
8373 bool NonStandardCompositeType = false;
8374 bool *BoolPtr = S.isSFINAEContext() ? nullptr : &NonStandardCompositeType;
8375 QualType T = S.FindCompositePointerType(Loc, LHS, RHS, BoolPtr);
8376 if (T.isNull()) {
8377 diagnoseDistinctPointerComparison(S, Loc, LHS, RHS, /*isError*/true);
8378 return true;
8379 }
8380
8381 if (NonStandardCompositeType)
8382 S.Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard)
8383 << LHSType << RHSType << T << LHS.get()->getSourceRange()
8384 << RHS.get()->getSourceRange();
8385
8386 LHS = S.ImpCastExprToType(LHS.get(), T, CK_BitCast);
8387 RHS = S.ImpCastExprToType(RHS.get(), T, CK_BitCast);
8388 return false;
8389 }
8390
diagnoseFunctionPointerToVoidComparison(Sema & S,SourceLocation Loc,ExprResult & LHS,ExprResult & RHS,bool IsError)8391 static void diagnoseFunctionPointerToVoidComparison(Sema &S, SourceLocation Loc,
8392 ExprResult &LHS,
8393 ExprResult &RHS,
8394 bool IsError) {
8395 S.Diag(Loc, IsError ? diag::err_typecheck_comparison_of_fptr_to_void
8396 : diag::ext_typecheck_comparison_of_fptr_to_void)
8397 << LHS.get()->getType() << RHS.get()->getType()
8398 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
8399 }
8400
isObjCObjectLiteral(ExprResult & E)8401 static bool isObjCObjectLiteral(ExprResult &E) {
8402 switch (E.get()->IgnoreParenImpCasts()->getStmtClass()) {
8403 case Stmt::ObjCArrayLiteralClass:
8404 case Stmt::ObjCDictionaryLiteralClass:
8405 case Stmt::ObjCStringLiteralClass:
8406 case Stmt::ObjCBoxedExprClass:
8407 return true;
8408 default:
8409 // Note that ObjCBoolLiteral is NOT an object literal!
8410 return false;
8411 }
8412 }
8413
hasIsEqualMethod(Sema & S,const Expr * LHS,const Expr * RHS)8414 static bool hasIsEqualMethod(Sema &S, const Expr *LHS, const Expr *RHS) {
8415 const ObjCObjectPointerType *Type =
8416 LHS->getType()->getAs<ObjCObjectPointerType>();
8417
8418 // If this is not actually an Objective-C object, bail out.
8419 if (!Type)
8420 return false;
8421
8422 // Get the LHS object's interface type.
8423 QualType InterfaceType = Type->getPointeeType();
8424
8425 // If the RHS isn't an Objective-C object, bail out.
8426 if (!RHS->getType()->isObjCObjectPointerType())
8427 return false;
8428
8429 // Try to find the -isEqual: method.
8430 Selector IsEqualSel = S.NSAPIObj->getIsEqualSelector();
8431 ObjCMethodDecl *Method = S.LookupMethodInObjectType(IsEqualSel,
8432 InterfaceType,
8433 /*instance=*/true);
8434 if (!Method) {
8435 if (Type->isObjCIdType()) {
8436 // For 'id', just check the global pool.
8437 Method = S.LookupInstanceMethodInGlobalPool(IsEqualSel, SourceRange(),
8438 /*receiverId=*/true);
8439 } else {
8440 // Check protocols.
8441 Method = S.LookupMethodInQualifiedType(IsEqualSel, Type,
8442 /*instance=*/true);
8443 }
8444 }
8445
8446 if (!Method)
8447 return false;
8448
8449 QualType T = Method->parameters()[0]->getType();
8450 if (!T->isObjCObjectPointerType())
8451 return false;
8452
8453 QualType R = Method->getReturnType();
8454 if (!R->isScalarType())
8455 return false;
8456
8457 return true;
8458 }
8459
CheckLiteralKind(Expr * FromE)8460 Sema::ObjCLiteralKind Sema::CheckLiteralKind(Expr *FromE) {
8461 FromE = FromE->IgnoreParenImpCasts();
8462 switch (FromE->getStmtClass()) {
8463 default:
8464 break;
8465 case Stmt::ObjCStringLiteralClass:
8466 // "string literal"
8467 return LK_String;
8468 case Stmt::ObjCArrayLiteralClass:
8469 // "array literal"
8470 return LK_Array;
8471 case Stmt::ObjCDictionaryLiteralClass:
8472 // "dictionary literal"
8473 return LK_Dictionary;
8474 case Stmt::BlockExprClass:
8475 return LK_Block;
8476 case Stmt::ObjCBoxedExprClass: {
8477 Expr *Inner = cast<ObjCBoxedExpr>(FromE)->getSubExpr()->IgnoreParens();
8478 switch (Inner->getStmtClass()) {
8479 case Stmt::IntegerLiteralClass:
8480 case Stmt::FloatingLiteralClass:
8481 case Stmt::CharacterLiteralClass:
8482 case Stmt::ObjCBoolLiteralExprClass:
8483 case Stmt::CXXBoolLiteralExprClass:
8484 // "numeric literal"
8485 return LK_Numeric;
8486 case Stmt::ImplicitCastExprClass: {
8487 CastKind CK = cast<CastExpr>(Inner)->getCastKind();
8488 // Boolean literals can be represented by implicit casts.
8489 if (CK == CK_IntegralToBoolean || CK == CK_IntegralCast)
8490 return LK_Numeric;
8491 break;
8492 }
8493 default:
8494 break;
8495 }
8496 return LK_Boxed;
8497 }
8498 }
8499 return LK_None;
8500 }
8501
diagnoseObjCLiteralComparison(Sema & S,SourceLocation Loc,ExprResult & LHS,ExprResult & RHS,BinaryOperator::Opcode Opc)8502 static void diagnoseObjCLiteralComparison(Sema &S, SourceLocation Loc,
8503 ExprResult &LHS, ExprResult &RHS,
8504 BinaryOperator::Opcode Opc){
8505 Expr *Literal;
8506 Expr *Other;
8507 if (isObjCObjectLiteral(LHS)) {
8508 Literal = LHS.get();
8509 Other = RHS.get();
8510 } else {
8511 Literal = RHS.get();
8512 Other = LHS.get();
8513 }
8514
8515 // Don't warn on comparisons against nil.
8516 Other = Other->IgnoreParenCasts();
8517 if (Other->isNullPointerConstant(S.getASTContext(),
8518 Expr::NPC_ValueDependentIsNotNull))
8519 return;
8520
8521 // This should be kept in sync with warn_objc_literal_comparison.
8522 // LK_String should always be after the other literals, since it has its own
8523 // warning flag.
8524 Sema::ObjCLiteralKind LiteralKind = S.CheckLiteralKind(Literal);
8525 assert(LiteralKind != Sema::LK_Block);
8526 if (LiteralKind == Sema::LK_None) {
8527 llvm_unreachable("Unknown Objective-C object literal kind");
8528 }
8529
8530 if (LiteralKind == Sema::LK_String)
8531 S.Diag(Loc, diag::warn_objc_string_literal_comparison)
8532 << Literal->getSourceRange();
8533 else
8534 S.Diag(Loc, diag::warn_objc_literal_comparison)
8535 << LiteralKind << Literal->getSourceRange();
8536
8537 if (BinaryOperator::isEqualityOp(Opc) &&
8538 hasIsEqualMethod(S, LHS.get(), RHS.get())) {
8539 SourceLocation Start = LHS.get()->getLocStart();
8540 SourceLocation End = S.getLocForEndOfToken(RHS.get()->getLocEnd());
8541 CharSourceRange OpRange =
8542 CharSourceRange::getCharRange(Loc, S.getLocForEndOfToken(Loc));
8543
8544 S.Diag(Loc, diag::note_objc_literal_comparison_isequal)
8545 << FixItHint::CreateInsertion(Start, Opc == BO_EQ ? "[" : "![")
8546 << FixItHint::CreateReplacement(OpRange, " isEqual:")
8547 << FixItHint::CreateInsertion(End, "]");
8548 }
8549 }
8550
diagnoseLogicalNotOnLHSofComparison(Sema & S,ExprResult & LHS,ExprResult & RHS,SourceLocation Loc,BinaryOperatorKind Opc)8551 static void diagnoseLogicalNotOnLHSofComparison(Sema &S, ExprResult &LHS,
8552 ExprResult &RHS,
8553 SourceLocation Loc,
8554 BinaryOperatorKind Opc) {
8555 // Check that left hand side is !something.
8556 UnaryOperator *UO = dyn_cast<UnaryOperator>(LHS.get()->IgnoreImpCasts());
8557 if (!UO || UO->getOpcode() != UO_LNot) return;
8558
8559 // Only check if the right hand side is non-bool arithmetic type.
8560 if (RHS.get()->isKnownToHaveBooleanValue()) return;
8561
8562 // Make sure that the something in !something is not bool.
8563 Expr *SubExpr = UO->getSubExpr()->IgnoreImpCasts();
8564 if (SubExpr->isKnownToHaveBooleanValue()) return;
8565
8566 // Emit warning.
8567 S.Diag(UO->getOperatorLoc(), diag::warn_logical_not_on_lhs_of_comparison)
8568 << Loc;
8569
8570 // First note suggest !(x < y)
8571 SourceLocation FirstOpen = SubExpr->getLocStart();
8572 SourceLocation FirstClose = RHS.get()->getLocEnd();
8573 FirstClose = S.getLocForEndOfToken(FirstClose);
8574 if (FirstClose.isInvalid())
8575 FirstOpen = SourceLocation();
8576 S.Diag(UO->getOperatorLoc(), diag::note_logical_not_fix)
8577 << FixItHint::CreateInsertion(FirstOpen, "(")
8578 << FixItHint::CreateInsertion(FirstClose, ")");
8579
8580 // Second note suggests (!x) < y
8581 SourceLocation SecondOpen = LHS.get()->getLocStart();
8582 SourceLocation SecondClose = LHS.get()->getLocEnd();
8583 SecondClose = S.getLocForEndOfToken(SecondClose);
8584 if (SecondClose.isInvalid())
8585 SecondOpen = SourceLocation();
8586 S.Diag(UO->getOperatorLoc(), diag::note_logical_not_silence_with_parens)
8587 << FixItHint::CreateInsertion(SecondOpen, "(")
8588 << FixItHint::CreateInsertion(SecondClose, ")");
8589 }
8590
8591 // Get the decl for a simple expression: a reference to a variable,
8592 // an implicit C++ field reference, or an implicit ObjC ivar reference.
getCompareDecl(Expr * E)8593 static ValueDecl *getCompareDecl(Expr *E) {
8594 if (DeclRefExpr* DR = dyn_cast<DeclRefExpr>(E))
8595 return DR->getDecl();
8596 if (ObjCIvarRefExpr* Ivar = dyn_cast<ObjCIvarRefExpr>(E)) {
8597 if (Ivar->isFreeIvar())
8598 return Ivar->getDecl();
8599 }
8600 if (MemberExpr* Mem = dyn_cast<MemberExpr>(E)) {
8601 if (Mem->isImplicitAccess())
8602 return Mem->getMemberDecl();
8603 }
8604 return nullptr;
8605 }
8606
8607 // C99 6.5.8, C++ [expr.rel]
CheckCompareOperands(ExprResult & LHS,ExprResult & RHS,SourceLocation Loc,BinaryOperatorKind Opc,bool IsRelational)8608 QualType Sema::CheckCompareOperands(ExprResult &LHS, ExprResult &RHS,
8609 SourceLocation Loc, BinaryOperatorKind Opc,
8610 bool IsRelational) {
8611 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/true);
8612
8613 // Handle vector comparisons separately.
8614 if (LHS.get()->getType()->isVectorType() ||
8615 RHS.get()->getType()->isVectorType())
8616 return CheckVectorCompareOperands(LHS, RHS, Loc, IsRelational);
8617
8618 QualType LHSType = LHS.get()->getType();
8619 QualType RHSType = RHS.get()->getType();
8620
8621 Expr *LHSStripped = LHS.get()->IgnoreParenImpCasts();
8622 Expr *RHSStripped = RHS.get()->IgnoreParenImpCasts();
8623
8624 checkEnumComparison(*this, Loc, LHS.get(), RHS.get());
8625 diagnoseLogicalNotOnLHSofComparison(*this, LHS, RHS, Loc, Opc);
8626
8627 if (!LHSType->hasFloatingRepresentation() &&
8628 !(LHSType->isBlockPointerType() && IsRelational) &&
8629 !LHS.get()->getLocStart().isMacroID() &&
8630 !RHS.get()->getLocStart().isMacroID() &&
8631 ActiveTemplateInstantiations.empty()) {
8632 // For non-floating point types, check for self-comparisons of the form
8633 // x == x, x != x, x < x, etc. These always evaluate to a constant, and
8634 // often indicate logic errors in the program.
8635 //
8636 // NOTE: Don't warn about comparison expressions resulting from macro
8637 // expansion. Also don't warn about comparisons which are only self
8638 // comparisons within a template specialization. The warnings should catch
8639 // obvious cases in the definition of the template anyways. The idea is to
8640 // warn when the typed comparison operator will always evaluate to the same
8641 // result.
8642 ValueDecl *DL = getCompareDecl(LHSStripped);
8643 ValueDecl *DR = getCompareDecl(RHSStripped);
8644 if (DL && DR && DL == DR && !IsWithinTemplateSpecialization(DL)) {
8645 DiagRuntimeBehavior(Loc, nullptr, PDiag(diag::warn_comparison_always)
8646 << 0 // self-
8647 << (Opc == BO_EQ
8648 || Opc == BO_LE
8649 || Opc == BO_GE));
8650 } else if (DL && DR && LHSType->isArrayType() && RHSType->isArrayType() &&
8651 !DL->getType()->isReferenceType() &&
8652 !DR->getType()->isReferenceType()) {
8653 // what is it always going to eval to?
8654 char always_evals_to;
8655 switch(Opc) {
8656 case BO_EQ: // e.g. array1 == array2
8657 always_evals_to = 0; // false
8658 break;
8659 case BO_NE: // e.g. array1 != array2
8660 always_evals_to = 1; // true
8661 break;
8662 default:
8663 // best we can say is 'a constant'
8664 always_evals_to = 2; // e.g. array1 <= array2
8665 break;
8666 }
8667 DiagRuntimeBehavior(Loc, nullptr, PDiag(diag::warn_comparison_always)
8668 << 1 // array
8669 << always_evals_to);
8670 }
8671
8672 if (isa<CastExpr>(LHSStripped))
8673 LHSStripped = LHSStripped->IgnoreParenCasts();
8674 if (isa<CastExpr>(RHSStripped))
8675 RHSStripped = RHSStripped->IgnoreParenCasts();
8676
8677 // Warn about comparisons against a string constant (unless the other
8678 // operand is null), the user probably wants strcmp.
8679 Expr *literalString = nullptr;
8680 Expr *literalStringStripped = nullptr;
8681 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) &&
8682 !RHSStripped->isNullPointerConstant(Context,
8683 Expr::NPC_ValueDependentIsNull)) {
8684 literalString = LHS.get();
8685 literalStringStripped = LHSStripped;
8686 } else if ((isa<StringLiteral>(RHSStripped) ||
8687 isa<ObjCEncodeExpr>(RHSStripped)) &&
8688 !LHSStripped->isNullPointerConstant(Context,
8689 Expr::NPC_ValueDependentIsNull)) {
8690 literalString = RHS.get();
8691 literalStringStripped = RHSStripped;
8692 }
8693
8694 if (literalString) {
8695 DiagRuntimeBehavior(Loc, nullptr,
8696 PDiag(diag::warn_stringcompare)
8697 << isa<ObjCEncodeExpr>(literalStringStripped)
8698 << literalString->getSourceRange());
8699 }
8700 }
8701
8702 // C99 6.5.8p3 / C99 6.5.9p4
8703 UsualArithmeticConversions(LHS, RHS);
8704 if (LHS.isInvalid() || RHS.isInvalid())
8705 return QualType();
8706
8707 LHSType = LHS.get()->getType();
8708 RHSType = RHS.get()->getType();
8709
8710 // The result of comparisons is 'bool' in C++, 'int' in C.
8711 QualType ResultTy = Context.getLogicalOperationType();
8712
8713 if (IsRelational) {
8714 if (LHSType->isRealType() && RHSType->isRealType())
8715 return ResultTy;
8716 } else {
8717 // Check for comparisons of floating point operands using != and ==.
8718 if (LHSType->hasFloatingRepresentation())
8719 CheckFloatComparison(Loc, LHS.get(), RHS.get());
8720
8721 if (LHSType->isArithmeticType() && RHSType->isArithmeticType())
8722 return ResultTy;
8723 }
8724
8725 const Expr::NullPointerConstantKind LHSNullKind =
8726 LHS.get()->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull);
8727 const Expr::NullPointerConstantKind RHSNullKind =
8728 RHS.get()->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull);
8729 bool LHSIsNull = LHSNullKind != Expr::NPCK_NotNull;
8730 bool RHSIsNull = RHSNullKind != Expr::NPCK_NotNull;
8731
8732 if (!IsRelational && LHSIsNull != RHSIsNull) {
8733 bool IsEquality = Opc == BO_EQ;
8734 if (RHSIsNull)
8735 DiagnoseAlwaysNonNullPointer(LHS.get(), RHSNullKind, IsEquality,
8736 RHS.get()->getSourceRange());
8737 else
8738 DiagnoseAlwaysNonNullPointer(RHS.get(), LHSNullKind, IsEquality,
8739 LHS.get()->getSourceRange());
8740 }
8741
8742 // All of the following pointer-related warnings are GCC extensions, except
8743 // when handling null pointer constants.
8744 if (LHSType->isPointerType() && RHSType->isPointerType()) { // C99 6.5.8p2
8745 QualType LCanPointeeTy =
8746 LHSType->castAs<PointerType>()->getPointeeType().getCanonicalType();
8747 QualType RCanPointeeTy =
8748 RHSType->castAs<PointerType>()->getPointeeType().getCanonicalType();
8749
8750 if (getLangOpts().CPlusPlus) {
8751 if (LCanPointeeTy == RCanPointeeTy)
8752 return ResultTy;
8753 if (!IsRelational &&
8754 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) {
8755 // Valid unless comparison between non-null pointer and function pointer
8756 // This is a gcc extension compatibility comparison.
8757 // In a SFINAE context, we treat this as a hard error to maintain
8758 // conformance with the C++ standard.
8759 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType())
8760 && !LHSIsNull && !RHSIsNull) {
8761 diagnoseFunctionPointerToVoidComparison(
8762 *this, Loc, LHS, RHS, /*isError*/ (bool)isSFINAEContext());
8763
8764 if (isSFINAEContext())
8765 return QualType();
8766
8767 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_BitCast);
8768 return ResultTy;
8769 }
8770 }
8771
8772 if (convertPointersToCompositeType(*this, Loc, LHS, RHS))
8773 return QualType();
8774 else
8775 return ResultTy;
8776 }
8777 // C99 6.5.9p2 and C99 6.5.8p2
8778 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(),
8779 RCanPointeeTy.getUnqualifiedType())) {
8780 // Valid unless a relational comparison of function pointers
8781 if (IsRelational && LCanPointeeTy->isFunctionType()) {
8782 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers)
8783 << LHSType << RHSType << LHS.get()->getSourceRange()
8784 << RHS.get()->getSourceRange();
8785 }
8786 } else if (!IsRelational &&
8787 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) {
8788 // Valid unless comparison between non-null pointer and function pointer
8789 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType())
8790 && !LHSIsNull && !RHSIsNull)
8791 diagnoseFunctionPointerToVoidComparison(*this, Loc, LHS, RHS,
8792 /*isError*/false);
8793 } else {
8794 // Invalid
8795 diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS, /*isError*/false);
8796 }
8797 if (LCanPointeeTy != RCanPointeeTy) {
8798 // Treat NULL constant as a special case in OpenCL.
8799 if (getLangOpts().OpenCL && !LHSIsNull && !RHSIsNull) {
8800 const PointerType *LHSPtr = LHSType->getAs<PointerType>();
8801 if (!LHSPtr->isAddressSpaceOverlapping(*RHSType->getAs<PointerType>())) {
8802 Diag(Loc,
8803 diag::err_typecheck_op_on_nonoverlapping_address_space_pointers)
8804 << LHSType << RHSType << 0 /* comparison */
8805 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
8806 }
8807 }
8808 unsigned AddrSpaceL = LCanPointeeTy.getAddressSpace();
8809 unsigned AddrSpaceR = RCanPointeeTy.getAddressSpace();
8810 CastKind Kind = AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion
8811 : CK_BitCast;
8812 if (LHSIsNull && !RHSIsNull)
8813 LHS = ImpCastExprToType(LHS.get(), RHSType, Kind);
8814 else
8815 RHS = ImpCastExprToType(RHS.get(), LHSType, Kind);
8816 }
8817 return ResultTy;
8818 }
8819
8820 if (getLangOpts().CPlusPlus) {
8821 // Comparison of nullptr_t with itself.
8822 if (LHSType->isNullPtrType() && RHSType->isNullPtrType())
8823 return ResultTy;
8824
8825 // Comparison of pointers with null pointer constants and equality
8826 // comparisons of member pointers to null pointer constants.
8827 if (RHSIsNull &&
8828 ((LHSType->isAnyPointerType() || LHSType->isNullPtrType()) ||
8829 (!IsRelational &&
8830 (LHSType->isMemberPointerType() || LHSType->isBlockPointerType())))) {
8831 RHS = ImpCastExprToType(RHS.get(), LHSType,
8832 LHSType->isMemberPointerType()
8833 ? CK_NullToMemberPointer
8834 : CK_NullToPointer);
8835 return ResultTy;
8836 }
8837 if (LHSIsNull &&
8838 ((RHSType->isAnyPointerType() || RHSType->isNullPtrType()) ||
8839 (!IsRelational &&
8840 (RHSType->isMemberPointerType() || RHSType->isBlockPointerType())))) {
8841 LHS = ImpCastExprToType(LHS.get(), RHSType,
8842 RHSType->isMemberPointerType()
8843 ? CK_NullToMemberPointer
8844 : CK_NullToPointer);
8845 return ResultTy;
8846 }
8847
8848 // Comparison of member pointers.
8849 if (!IsRelational &&
8850 LHSType->isMemberPointerType() && RHSType->isMemberPointerType()) {
8851 if (convertPointersToCompositeType(*this, Loc, LHS, RHS))
8852 return QualType();
8853 else
8854 return ResultTy;
8855 }
8856
8857 // Handle scoped enumeration types specifically, since they don't promote
8858 // to integers.
8859 if (LHS.get()->getType()->isEnumeralType() &&
8860 Context.hasSameUnqualifiedType(LHS.get()->getType(),
8861 RHS.get()->getType()))
8862 return ResultTy;
8863 }
8864
8865 // Handle block pointer types.
8866 if (!IsRelational && LHSType->isBlockPointerType() &&
8867 RHSType->isBlockPointerType()) {
8868 QualType lpointee = LHSType->castAs<BlockPointerType>()->getPointeeType();
8869 QualType rpointee = RHSType->castAs<BlockPointerType>()->getPointeeType();
8870
8871 if (!LHSIsNull && !RHSIsNull &&
8872 !Context.typesAreCompatible(lpointee, rpointee)) {
8873 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks)
8874 << LHSType << RHSType << LHS.get()->getSourceRange()
8875 << RHS.get()->getSourceRange();
8876 }
8877 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_BitCast);
8878 return ResultTy;
8879 }
8880
8881 // Allow block pointers to be compared with null pointer constants.
8882 if (!IsRelational
8883 && ((LHSType->isBlockPointerType() && RHSType->isPointerType())
8884 || (LHSType->isPointerType() && RHSType->isBlockPointerType()))) {
8885 if (!LHSIsNull && !RHSIsNull) {
8886 if (!((RHSType->isPointerType() && RHSType->castAs<PointerType>()
8887 ->getPointeeType()->isVoidType())
8888 || (LHSType->isPointerType() && LHSType->castAs<PointerType>()
8889 ->getPointeeType()->isVoidType())))
8890 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks)
8891 << LHSType << RHSType << LHS.get()->getSourceRange()
8892 << RHS.get()->getSourceRange();
8893 }
8894 if (LHSIsNull && !RHSIsNull)
8895 LHS = ImpCastExprToType(LHS.get(), RHSType,
8896 RHSType->isPointerType() ? CK_BitCast
8897 : CK_AnyPointerToBlockPointerCast);
8898 else
8899 RHS = ImpCastExprToType(RHS.get(), LHSType,
8900 LHSType->isPointerType() ? CK_BitCast
8901 : CK_AnyPointerToBlockPointerCast);
8902 return ResultTy;
8903 }
8904
8905 if (LHSType->isObjCObjectPointerType() ||
8906 RHSType->isObjCObjectPointerType()) {
8907 const PointerType *LPT = LHSType->getAs<PointerType>();
8908 const PointerType *RPT = RHSType->getAs<PointerType>();
8909 if (LPT || RPT) {
8910 bool LPtrToVoid = LPT ? LPT->getPointeeType()->isVoidType() : false;
8911 bool RPtrToVoid = RPT ? RPT->getPointeeType()->isVoidType() : false;
8912
8913 if (!LPtrToVoid && !RPtrToVoid &&
8914 !Context.typesAreCompatible(LHSType, RHSType)) {
8915 diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS,
8916 /*isError*/false);
8917 }
8918 if (LHSIsNull && !RHSIsNull) {
8919 Expr *E = LHS.get();
8920 if (getLangOpts().ObjCAutoRefCount)
8921 CheckObjCARCConversion(SourceRange(), RHSType, E, CCK_ImplicitConversion);
8922 LHS = ImpCastExprToType(E, RHSType,
8923 RPT ? CK_BitCast :CK_CPointerToObjCPointerCast);
8924 }
8925 else {
8926 Expr *E = RHS.get();
8927 if (getLangOpts().ObjCAutoRefCount)
8928 CheckObjCARCConversion(SourceRange(), LHSType, E, CCK_ImplicitConversion, false,
8929 Opc);
8930 RHS = ImpCastExprToType(E, LHSType,
8931 LPT ? CK_BitCast :CK_CPointerToObjCPointerCast);
8932 }
8933 return ResultTy;
8934 }
8935 if (LHSType->isObjCObjectPointerType() &&
8936 RHSType->isObjCObjectPointerType()) {
8937 if (!Context.areComparableObjCPointerTypes(LHSType, RHSType))
8938 diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS,
8939 /*isError*/false);
8940 if (isObjCObjectLiteral(LHS) || isObjCObjectLiteral(RHS))
8941 diagnoseObjCLiteralComparison(*this, Loc, LHS, RHS, Opc);
8942
8943 if (LHSIsNull && !RHSIsNull)
8944 LHS = ImpCastExprToType(LHS.get(), RHSType, CK_BitCast);
8945 else
8946 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_BitCast);
8947 return ResultTy;
8948 }
8949 }
8950 if ((LHSType->isAnyPointerType() && RHSType->isIntegerType()) ||
8951 (LHSType->isIntegerType() && RHSType->isAnyPointerType())) {
8952 unsigned DiagID = 0;
8953 bool isError = false;
8954 if (LangOpts.DebuggerSupport) {
8955 // Under a debugger, allow the comparison of pointers to integers,
8956 // since users tend to want to compare addresses.
8957 } else if ((LHSIsNull && LHSType->isIntegerType()) ||
8958 (RHSIsNull && RHSType->isIntegerType())) {
8959 if (IsRelational && !getLangOpts().CPlusPlus)
8960 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero;
8961 } else if (IsRelational && !getLangOpts().CPlusPlus)
8962 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer;
8963 else if (getLangOpts().CPlusPlus) {
8964 DiagID = diag::err_typecheck_comparison_of_pointer_integer;
8965 isError = true;
8966 } else
8967 DiagID = diag::ext_typecheck_comparison_of_pointer_integer;
8968
8969 if (DiagID) {
8970 Diag(Loc, DiagID)
8971 << LHSType << RHSType << LHS.get()->getSourceRange()
8972 << RHS.get()->getSourceRange();
8973 if (isError)
8974 return QualType();
8975 }
8976
8977 if (LHSType->isIntegerType())
8978 LHS = ImpCastExprToType(LHS.get(), RHSType,
8979 LHSIsNull ? CK_NullToPointer : CK_IntegralToPointer);
8980 else
8981 RHS = ImpCastExprToType(RHS.get(), LHSType,
8982 RHSIsNull ? CK_NullToPointer : CK_IntegralToPointer);
8983 return ResultTy;
8984 }
8985
8986 // Handle block pointers.
8987 if (!IsRelational && RHSIsNull
8988 && LHSType->isBlockPointerType() && RHSType->isIntegerType()) {
8989 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_NullToPointer);
8990 return ResultTy;
8991 }
8992 if (!IsRelational && LHSIsNull
8993 && LHSType->isIntegerType() && RHSType->isBlockPointerType()) {
8994 LHS = ImpCastExprToType(LHS.get(), RHSType, CK_NullToPointer);
8995 return ResultTy;
8996 }
8997
8998 return InvalidOperands(Loc, LHS, RHS);
8999 }
9000
9001
9002 // Return a signed type that is of identical size and number of elements.
9003 // For floating point vectors, return an integer type of identical size
9004 // and number of elements.
GetSignedVectorType(QualType V)9005 QualType Sema::GetSignedVectorType(QualType V) {
9006 const VectorType *VTy = V->getAs<VectorType>();
9007 unsigned TypeSize = Context.getTypeSize(VTy->getElementType());
9008 if (TypeSize == Context.getTypeSize(Context.CharTy))
9009 return Context.getExtVectorType(Context.CharTy, VTy->getNumElements());
9010 else if (TypeSize == Context.getTypeSize(Context.ShortTy))
9011 return Context.getExtVectorType(Context.ShortTy, VTy->getNumElements());
9012 else if (TypeSize == Context.getTypeSize(Context.IntTy))
9013 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements());
9014 else if (TypeSize == Context.getTypeSize(Context.LongTy))
9015 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements());
9016 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) &&
9017 "Unhandled vector element size in vector compare");
9018 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements());
9019 }
9020
9021 /// CheckVectorCompareOperands - vector comparisons are a clang extension that
9022 /// operates on extended vector types. Instead of producing an IntTy result,
9023 /// like a scalar comparison, a vector comparison produces a vector of integer
9024 /// types.
CheckVectorCompareOperands(ExprResult & LHS,ExprResult & RHS,SourceLocation Loc,bool IsRelational)9025 QualType Sema::CheckVectorCompareOperands(ExprResult &LHS, ExprResult &RHS,
9026 SourceLocation Loc,
9027 bool IsRelational) {
9028 // Check to make sure we're operating on vectors of the same type and width,
9029 // Allowing one side to be a scalar of element type.
9030 QualType vType = CheckVectorOperands(LHS, RHS, Loc, /*isCompAssign*/false,
9031 /*AllowBothBool*/true,
9032 /*AllowBoolConversions*/getLangOpts().ZVector);
9033 if (vType.isNull())
9034 return vType;
9035
9036 QualType LHSType = LHS.get()->getType();
9037
9038 // If AltiVec, the comparison results in a numeric type, i.e.
9039 // bool for C++, int for C
9040 if (getLangOpts().AltiVec &&
9041 vType->getAs<VectorType>()->getVectorKind() == VectorType::AltiVecVector)
9042 return Context.getLogicalOperationType();
9043
9044 // For non-floating point types, check for self-comparisons of the form
9045 // x == x, x != x, x < x, etc. These always evaluate to a constant, and
9046 // often indicate logic errors in the program.
9047 if (!LHSType->hasFloatingRepresentation() &&
9048 ActiveTemplateInstantiations.empty()) {
9049 if (DeclRefExpr* DRL
9050 = dyn_cast<DeclRefExpr>(LHS.get()->IgnoreParenImpCasts()))
9051 if (DeclRefExpr* DRR
9052 = dyn_cast<DeclRefExpr>(RHS.get()->IgnoreParenImpCasts()))
9053 if (DRL->getDecl() == DRR->getDecl())
9054 DiagRuntimeBehavior(Loc, nullptr,
9055 PDiag(diag::warn_comparison_always)
9056 << 0 // self-
9057 << 2 // "a constant"
9058 );
9059 }
9060
9061 // Check for comparisons of floating point operands using != and ==.
9062 if (!IsRelational && LHSType->hasFloatingRepresentation()) {
9063 assert (RHS.get()->getType()->hasFloatingRepresentation());
9064 CheckFloatComparison(Loc, LHS.get(), RHS.get());
9065 }
9066
9067 // Return a signed type for the vector.
9068 return GetSignedVectorType(LHSType);
9069 }
9070
CheckVectorLogicalOperands(ExprResult & LHS,ExprResult & RHS,SourceLocation Loc)9071 QualType Sema::CheckVectorLogicalOperands(ExprResult &LHS, ExprResult &RHS,
9072 SourceLocation Loc) {
9073 // Ensure that either both operands are of the same vector type, or
9074 // one operand is of a vector type and the other is of its element type.
9075 QualType vType = CheckVectorOperands(LHS, RHS, Loc, false,
9076 /*AllowBothBool*/true,
9077 /*AllowBoolConversions*/false);
9078 if (vType.isNull())
9079 return InvalidOperands(Loc, LHS, RHS);
9080 if (getLangOpts().OpenCL && getLangOpts().OpenCLVersion < 120 &&
9081 vType->hasFloatingRepresentation())
9082 return InvalidOperands(Loc, LHS, RHS);
9083
9084 return GetSignedVectorType(LHS.get()->getType());
9085 }
9086
CheckBitwiseOperands(ExprResult & LHS,ExprResult & RHS,SourceLocation Loc,bool IsCompAssign)9087 inline QualType Sema::CheckBitwiseOperands(
9088 ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, bool IsCompAssign) {
9089 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
9090
9091 if (LHS.get()->getType()->isVectorType() ||
9092 RHS.get()->getType()->isVectorType()) {
9093 if (LHS.get()->getType()->hasIntegerRepresentation() &&
9094 RHS.get()->getType()->hasIntegerRepresentation())
9095 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign,
9096 /*AllowBothBool*/true,
9097 /*AllowBoolConversions*/getLangOpts().ZVector);
9098 return InvalidOperands(Loc, LHS, RHS);
9099 }
9100
9101 ExprResult LHSResult = LHS, RHSResult = RHS;
9102 QualType compType = UsualArithmeticConversions(LHSResult, RHSResult,
9103 IsCompAssign);
9104 if (LHSResult.isInvalid() || RHSResult.isInvalid())
9105 return QualType();
9106 LHS = LHSResult.get();
9107 RHS = RHSResult.get();
9108
9109 if (!compType.isNull() && compType->isIntegralOrUnscopedEnumerationType())
9110 return compType;
9111 return InvalidOperands(Loc, LHS, RHS);
9112 }
9113
9114 // C99 6.5.[13,14]
CheckLogicalOperands(ExprResult & LHS,ExprResult & RHS,SourceLocation Loc,BinaryOperatorKind Opc)9115 inline QualType Sema::CheckLogicalOperands(ExprResult &LHS, ExprResult &RHS,
9116 SourceLocation Loc,
9117 BinaryOperatorKind Opc) {
9118 // Check vector operands differently.
9119 if (LHS.get()->getType()->isVectorType() || RHS.get()->getType()->isVectorType())
9120 return CheckVectorLogicalOperands(LHS, RHS, Loc);
9121
9122 // Diagnose cases where the user write a logical and/or but probably meant a
9123 // bitwise one. We do this when the LHS is a non-bool integer and the RHS
9124 // is a constant.
9125 if (LHS.get()->getType()->isIntegerType() &&
9126 !LHS.get()->getType()->isBooleanType() &&
9127 RHS.get()->getType()->isIntegerType() && !RHS.get()->isValueDependent() &&
9128 // Don't warn in macros or template instantiations.
9129 !Loc.isMacroID() && ActiveTemplateInstantiations.empty()) {
9130 // If the RHS can be constant folded, and if it constant folds to something
9131 // that isn't 0 or 1 (which indicate a potential logical operation that
9132 // happened to fold to true/false) then warn.
9133 // Parens on the RHS are ignored.
9134 llvm::APSInt Result;
9135 if (RHS.get()->EvaluateAsInt(Result, Context))
9136 if ((getLangOpts().Bool && !RHS.get()->getType()->isBooleanType() &&
9137 !RHS.get()->getExprLoc().isMacroID()) ||
9138 (Result != 0 && Result != 1)) {
9139 Diag(Loc, diag::warn_logical_instead_of_bitwise)
9140 << RHS.get()->getSourceRange()
9141 << (Opc == BO_LAnd ? "&&" : "||");
9142 // Suggest replacing the logical operator with the bitwise version
9143 Diag(Loc, diag::note_logical_instead_of_bitwise_change_operator)
9144 << (Opc == BO_LAnd ? "&" : "|")
9145 << FixItHint::CreateReplacement(SourceRange(
9146 Loc, getLocForEndOfToken(Loc)),
9147 Opc == BO_LAnd ? "&" : "|");
9148 if (Opc == BO_LAnd)
9149 // Suggest replacing "Foo() && kNonZero" with "Foo()"
9150 Diag(Loc, diag::note_logical_instead_of_bitwise_remove_constant)
9151 << FixItHint::CreateRemoval(
9152 SourceRange(getLocForEndOfToken(LHS.get()->getLocEnd()),
9153 RHS.get()->getLocEnd()));
9154 }
9155 }
9156
9157 if (!Context.getLangOpts().CPlusPlus) {
9158 // OpenCL v1.1 s6.3.g: The logical operators and (&&), or (||) do
9159 // not operate on the built-in scalar and vector float types.
9160 if (Context.getLangOpts().OpenCL &&
9161 Context.getLangOpts().OpenCLVersion < 120) {
9162 if (LHS.get()->getType()->isFloatingType() ||
9163 RHS.get()->getType()->isFloatingType())
9164 return InvalidOperands(Loc, LHS, RHS);
9165 }
9166
9167 LHS = UsualUnaryConversions(LHS.get());
9168 if (LHS.isInvalid())
9169 return QualType();
9170
9171 RHS = UsualUnaryConversions(RHS.get());
9172 if (RHS.isInvalid())
9173 return QualType();
9174
9175 if (!LHS.get()->getType()->isScalarType() ||
9176 !RHS.get()->getType()->isScalarType())
9177 return InvalidOperands(Loc, LHS, RHS);
9178
9179 return Context.IntTy;
9180 }
9181
9182 // The following is safe because we only use this method for
9183 // non-overloadable operands.
9184
9185 // C++ [expr.log.and]p1
9186 // C++ [expr.log.or]p1
9187 // The operands are both contextually converted to type bool.
9188 ExprResult LHSRes = PerformContextuallyConvertToBool(LHS.get());
9189 if (LHSRes.isInvalid())
9190 return InvalidOperands(Loc, LHS, RHS);
9191 LHS = LHSRes;
9192
9193 ExprResult RHSRes = PerformContextuallyConvertToBool(RHS.get());
9194 if (RHSRes.isInvalid())
9195 return InvalidOperands(Loc, LHS, RHS);
9196 RHS = RHSRes;
9197
9198 // C++ [expr.log.and]p2
9199 // C++ [expr.log.or]p2
9200 // The result is a bool.
9201 return Context.BoolTy;
9202 }
9203
IsReadonlyMessage(Expr * E,Sema & S)9204 static bool IsReadonlyMessage(Expr *E, Sema &S) {
9205 const MemberExpr *ME = dyn_cast<MemberExpr>(E);
9206 if (!ME) return false;
9207 if (!isa<FieldDecl>(ME->getMemberDecl())) return false;
9208 ObjCMessageExpr *Base =
9209 dyn_cast<ObjCMessageExpr>(ME->getBase()->IgnoreParenImpCasts());
9210 if (!Base) return false;
9211 return Base->getMethodDecl() != nullptr;
9212 }
9213
9214 /// Is the given expression (which must be 'const') a reference to a
9215 /// variable which was originally non-const, but which has become
9216 /// 'const' due to being captured within a block?
9217 enum NonConstCaptureKind { NCCK_None, NCCK_Block, NCCK_Lambda };
isReferenceToNonConstCapture(Sema & S,Expr * E)9218 static NonConstCaptureKind isReferenceToNonConstCapture(Sema &S, Expr *E) {
9219 assert(E->isLValue() && E->getType().isConstQualified());
9220 E = E->IgnoreParens();
9221
9222 // Must be a reference to a declaration from an enclosing scope.
9223 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E);
9224 if (!DRE) return NCCK_None;
9225 if (!DRE->refersToEnclosingVariableOrCapture()) return NCCK_None;
9226
9227 // The declaration must be a variable which is not declared 'const'.
9228 VarDecl *var = dyn_cast<VarDecl>(DRE->getDecl());
9229 if (!var) return NCCK_None;
9230 if (var->getType().isConstQualified()) return NCCK_None;
9231 assert(var->hasLocalStorage() && "capture added 'const' to non-local?");
9232
9233 // Decide whether the first capture was for a block or a lambda.
9234 DeclContext *DC = S.CurContext, *Prev = nullptr;
9235 while (DC != var->getDeclContext()) {
9236 Prev = DC;
9237 DC = DC->getParent();
9238 }
9239 // Unless we have an init-capture, we've gone one step too far.
9240 if (!var->isInitCapture())
9241 DC = Prev;
9242 return (isa<BlockDecl>(DC) ? NCCK_Block : NCCK_Lambda);
9243 }
9244
IsTypeModifiable(QualType Ty,bool IsDereference)9245 static bool IsTypeModifiable(QualType Ty, bool IsDereference) {
9246 Ty = Ty.getNonReferenceType();
9247 if (IsDereference && Ty->isPointerType())
9248 Ty = Ty->getPointeeType();
9249 return !Ty.isConstQualified();
9250 }
9251
9252 /// Emit the "read-only variable not assignable" error and print notes to give
9253 /// more information about why the variable is not assignable, such as pointing
9254 /// to the declaration of a const variable, showing that a method is const, or
9255 /// that the function is returning a const reference.
DiagnoseConstAssignment(Sema & S,const Expr * E,SourceLocation Loc)9256 static void DiagnoseConstAssignment(Sema &S, const Expr *E,
9257 SourceLocation Loc) {
9258 // Update err_typecheck_assign_const and note_typecheck_assign_const
9259 // when this enum is changed.
9260 enum {
9261 ConstFunction,
9262 ConstVariable,
9263 ConstMember,
9264 ConstMethod,
9265 ConstUnknown, // Keep as last element
9266 };
9267
9268 SourceRange ExprRange = E->getSourceRange();
9269
9270 // Only emit one error on the first const found. All other consts will emit
9271 // a note to the error.
9272 bool DiagnosticEmitted = false;
9273
9274 // Track if the current expression is the result of a derefence, and if the
9275 // next checked expression is the result of a derefence.
9276 bool IsDereference = false;
9277 bool NextIsDereference = false;
9278
9279 // Loop to process MemberExpr chains.
9280 while (true) {
9281 IsDereference = NextIsDereference;
9282 NextIsDereference = false;
9283
9284 E = E->IgnoreParenImpCasts();
9285 if (const MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
9286 NextIsDereference = ME->isArrow();
9287 const ValueDecl *VD = ME->getMemberDecl();
9288 if (const FieldDecl *Field = dyn_cast<FieldDecl>(VD)) {
9289 // Mutable fields can be modified even if the class is const.
9290 if (Field->isMutable()) {
9291 assert(DiagnosticEmitted && "Expected diagnostic not emitted.");
9292 break;
9293 }
9294
9295 if (!IsTypeModifiable(Field->getType(), IsDereference)) {
9296 if (!DiagnosticEmitted) {
9297 S.Diag(Loc, diag::err_typecheck_assign_const)
9298 << ExprRange << ConstMember << false /*static*/ << Field
9299 << Field->getType();
9300 DiagnosticEmitted = true;
9301 }
9302 S.Diag(VD->getLocation(), diag::note_typecheck_assign_const)
9303 << ConstMember << false /*static*/ << Field << Field->getType()
9304 << Field->getSourceRange();
9305 }
9306 E = ME->getBase();
9307 continue;
9308 } else if (const VarDecl *VDecl = dyn_cast<VarDecl>(VD)) {
9309 if (VDecl->getType().isConstQualified()) {
9310 if (!DiagnosticEmitted) {
9311 S.Diag(Loc, diag::err_typecheck_assign_const)
9312 << ExprRange << ConstMember << true /*static*/ << VDecl
9313 << VDecl->getType();
9314 DiagnosticEmitted = true;
9315 }
9316 S.Diag(VD->getLocation(), diag::note_typecheck_assign_const)
9317 << ConstMember << true /*static*/ << VDecl << VDecl->getType()
9318 << VDecl->getSourceRange();
9319 }
9320 // Static fields do not inherit constness from parents.
9321 break;
9322 }
9323 break;
9324 } // End MemberExpr
9325 break;
9326 }
9327
9328 if (const CallExpr *CE = dyn_cast<CallExpr>(E)) {
9329 // Function calls
9330 const FunctionDecl *FD = CE->getDirectCallee();
9331 if (FD && !IsTypeModifiable(FD->getReturnType(), IsDereference)) {
9332 if (!DiagnosticEmitted) {
9333 S.Diag(Loc, diag::err_typecheck_assign_const) << ExprRange
9334 << ConstFunction << FD;
9335 DiagnosticEmitted = true;
9336 }
9337 S.Diag(FD->getReturnTypeSourceRange().getBegin(),
9338 diag::note_typecheck_assign_const)
9339 << ConstFunction << FD << FD->getReturnType()
9340 << FD->getReturnTypeSourceRange();
9341 }
9342 } else if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
9343 // Point to variable declaration.
9344 if (const ValueDecl *VD = DRE->getDecl()) {
9345 if (!IsTypeModifiable(VD->getType(), IsDereference)) {
9346 if (!DiagnosticEmitted) {
9347 S.Diag(Loc, diag::err_typecheck_assign_const)
9348 << ExprRange << ConstVariable << VD << VD->getType();
9349 DiagnosticEmitted = true;
9350 }
9351 S.Diag(VD->getLocation(), diag::note_typecheck_assign_const)
9352 << ConstVariable << VD << VD->getType() << VD->getSourceRange();
9353 }
9354 }
9355 } else if (isa<CXXThisExpr>(E)) {
9356 if (const DeclContext *DC = S.getFunctionLevelDeclContext()) {
9357 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) {
9358 if (MD->isConst()) {
9359 if (!DiagnosticEmitted) {
9360 S.Diag(Loc, diag::err_typecheck_assign_const) << ExprRange
9361 << ConstMethod << MD;
9362 DiagnosticEmitted = true;
9363 }
9364 S.Diag(MD->getLocation(), diag::note_typecheck_assign_const)
9365 << ConstMethod << MD << MD->getSourceRange();
9366 }
9367 }
9368 }
9369 }
9370
9371 if (DiagnosticEmitted)
9372 return;
9373
9374 // Can't determine a more specific message, so display the generic error.
9375 S.Diag(Loc, diag::err_typecheck_assign_const) << ExprRange << ConstUnknown;
9376 }
9377
9378 /// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not,
9379 /// emit an error and return true. If so, return false.
CheckForModifiableLvalue(Expr * E,SourceLocation Loc,Sema & S)9380 static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) {
9381 assert(!E->hasPlaceholderType(BuiltinType::PseudoObject));
9382 SourceLocation OrigLoc = Loc;
9383 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context,
9384 &Loc);
9385 if (IsLV == Expr::MLV_ClassTemporary && IsReadonlyMessage(E, S))
9386 IsLV = Expr::MLV_InvalidMessageExpression;
9387 if (IsLV == Expr::MLV_Valid)
9388 return false;
9389
9390 unsigned DiagID = 0;
9391 bool NeedType = false;
9392 switch (IsLV) { // C99 6.5.16p2
9393 case Expr::MLV_ConstQualified:
9394 // Use a specialized diagnostic when we're assigning to an object
9395 // from an enclosing function or block.
9396 if (NonConstCaptureKind NCCK = isReferenceToNonConstCapture(S, E)) {
9397 if (NCCK == NCCK_Block)
9398 DiagID = diag::err_block_decl_ref_not_modifiable_lvalue;
9399 else
9400 DiagID = diag::err_lambda_decl_ref_not_modifiable_lvalue;
9401 break;
9402 }
9403
9404 // In ARC, use some specialized diagnostics for occasions where we
9405 // infer 'const'. These are always pseudo-strong variables.
9406 if (S.getLangOpts().ObjCAutoRefCount) {
9407 DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(E->IgnoreParenCasts());
9408 if (declRef && isa<VarDecl>(declRef->getDecl())) {
9409 VarDecl *var = cast<VarDecl>(declRef->getDecl());
9410
9411 // Use the normal diagnostic if it's pseudo-__strong but the
9412 // user actually wrote 'const'.
9413 if (var->isARCPseudoStrong() &&
9414 (!var->getTypeSourceInfo() ||
9415 !var->getTypeSourceInfo()->getType().isConstQualified())) {
9416 // There are two pseudo-strong cases:
9417 // - self
9418 ObjCMethodDecl *method = S.getCurMethodDecl();
9419 if (method && var == method->getSelfDecl())
9420 DiagID = method->isClassMethod()
9421 ? diag::err_typecheck_arc_assign_self_class_method
9422 : diag::err_typecheck_arc_assign_self;
9423
9424 // - fast enumeration variables
9425 else
9426 DiagID = diag::err_typecheck_arr_assign_enumeration;
9427
9428 SourceRange Assign;
9429 if (Loc != OrigLoc)
9430 Assign = SourceRange(OrigLoc, OrigLoc);
9431 S.Diag(Loc, DiagID) << E->getSourceRange() << Assign;
9432 // We need to preserve the AST regardless, so migration tool
9433 // can do its job.
9434 return false;
9435 }
9436 }
9437 }
9438
9439 // If none of the special cases above are triggered, then this is a
9440 // simple const assignment.
9441 if (DiagID == 0) {
9442 DiagnoseConstAssignment(S, E, Loc);
9443 return true;
9444 }
9445
9446 break;
9447 case Expr::MLV_ConstAddrSpace:
9448 DiagnoseConstAssignment(S, E, Loc);
9449 return true;
9450 case Expr::MLV_ArrayType:
9451 case Expr::MLV_ArrayTemporary:
9452 DiagID = diag::err_typecheck_array_not_modifiable_lvalue;
9453 NeedType = true;
9454 break;
9455 case Expr::MLV_NotObjectType:
9456 DiagID = diag::err_typecheck_non_object_not_modifiable_lvalue;
9457 NeedType = true;
9458 break;
9459 case Expr::MLV_LValueCast:
9460 DiagID = diag::err_typecheck_lvalue_casts_not_supported;
9461 break;
9462 case Expr::MLV_Valid:
9463 llvm_unreachable("did not take early return for MLV_Valid");
9464 case Expr::MLV_InvalidExpression:
9465 case Expr::MLV_MemberFunction:
9466 case Expr::MLV_ClassTemporary:
9467 DiagID = diag::err_typecheck_expression_not_modifiable_lvalue;
9468 break;
9469 case Expr::MLV_IncompleteType:
9470 case Expr::MLV_IncompleteVoidType:
9471 return S.RequireCompleteType(Loc, E->getType(),
9472 diag::err_typecheck_incomplete_type_not_modifiable_lvalue, E);
9473 case Expr::MLV_DuplicateVectorComponents:
9474 DiagID = diag::err_typecheck_duplicate_vector_components_not_mlvalue;
9475 break;
9476 case Expr::MLV_NoSetterProperty:
9477 llvm_unreachable("readonly properties should be processed differently");
9478 case Expr::MLV_InvalidMessageExpression:
9479 DiagID = diag::error_readonly_message_assignment;
9480 break;
9481 case Expr::MLV_SubObjCPropertySetting:
9482 DiagID = diag::error_no_subobject_property_setting;
9483 break;
9484 }
9485
9486 SourceRange Assign;
9487 if (Loc != OrigLoc)
9488 Assign = SourceRange(OrigLoc, OrigLoc);
9489 if (NeedType)
9490 S.Diag(Loc, DiagID) << E->getType() << E->getSourceRange() << Assign;
9491 else
9492 S.Diag(Loc, DiagID) << E->getSourceRange() << Assign;
9493 return true;
9494 }
9495
CheckIdentityFieldAssignment(Expr * LHSExpr,Expr * RHSExpr,SourceLocation Loc,Sema & Sema)9496 static void CheckIdentityFieldAssignment(Expr *LHSExpr, Expr *RHSExpr,
9497 SourceLocation Loc,
9498 Sema &Sema) {
9499 // C / C++ fields
9500 MemberExpr *ML = dyn_cast<MemberExpr>(LHSExpr);
9501 MemberExpr *MR = dyn_cast<MemberExpr>(RHSExpr);
9502 if (ML && MR && ML->getMemberDecl() == MR->getMemberDecl()) {
9503 if (isa<CXXThisExpr>(ML->getBase()) && isa<CXXThisExpr>(MR->getBase()))
9504 Sema.Diag(Loc, diag::warn_identity_field_assign) << 0;
9505 }
9506
9507 // Objective-C instance variables
9508 ObjCIvarRefExpr *OL = dyn_cast<ObjCIvarRefExpr>(LHSExpr);
9509 ObjCIvarRefExpr *OR = dyn_cast<ObjCIvarRefExpr>(RHSExpr);
9510 if (OL && OR && OL->getDecl() == OR->getDecl()) {
9511 DeclRefExpr *RL = dyn_cast<DeclRefExpr>(OL->getBase()->IgnoreImpCasts());
9512 DeclRefExpr *RR = dyn_cast<DeclRefExpr>(OR->getBase()->IgnoreImpCasts());
9513 if (RL && RR && RL->getDecl() == RR->getDecl())
9514 Sema.Diag(Loc, diag::warn_identity_field_assign) << 1;
9515 }
9516 }
9517
9518 // C99 6.5.16.1
CheckAssignmentOperands(Expr * LHSExpr,ExprResult & RHS,SourceLocation Loc,QualType CompoundType)9519 QualType Sema::CheckAssignmentOperands(Expr *LHSExpr, ExprResult &RHS,
9520 SourceLocation Loc,
9521 QualType CompoundType) {
9522 assert(!LHSExpr->hasPlaceholderType(BuiltinType::PseudoObject));
9523
9524 // Verify that LHS is a modifiable lvalue, and emit error if not.
9525 if (CheckForModifiableLvalue(LHSExpr, Loc, *this))
9526 return QualType();
9527
9528 QualType LHSType = LHSExpr->getType();
9529 QualType RHSType = CompoundType.isNull() ? RHS.get()->getType() :
9530 CompoundType;
9531 AssignConvertType ConvTy;
9532 if (CompoundType.isNull()) {
9533 Expr *RHSCheck = RHS.get();
9534
9535 CheckIdentityFieldAssignment(LHSExpr, RHSCheck, Loc, *this);
9536
9537 QualType LHSTy(LHSType);
9538 ConvTy = CheckSingleAssignmentConstraints(LHSTy, RHS);
9539 if (RHS.isInvalid())
9540 return QualType();
9541 // Special case of NSObject attributes on c-style pointer types.
9542 if (ConvTy == IncompatiblePointer &&
9543 ((Context.isObjCNSObjectType(LHSType) &&
9544 RHSType->isObjCObjectPointerType()) ||
9545 (Context.isObjCNSObjectType(RHSType) &&
9546 LHSType->isObjCObjectPointerType())))
9547 ConvTy = Compatible;
9548
9549 if (ConvTy == Compatible &&
9550 LHSType->isObjCObjectType())
9551 Diag(Loc, diag::err_objc_object_assignment)
9552 << LHSType;
9553
9554 // If the RHS is a unary plus or minus, check to see if they = and + are
9555 // right next to each other. If so, the user may have typo'd "x =+ 4"
9556 // instead of "x += 4".
9557 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck))
9558 RHSCheck = ICE->getSubExpr();
9559 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) {
9560 if ((UO->getOpcode() == UO_Plus ||
9561 UO->getOpcode() == UO_Minus) &&
9562 Loc.isFileID() && UO->getOperatorLoc().isFileID() &&
9563 // Only if the two operators are exactly adjacent.
9564 Loc.getLocWithOffset(1) == UO->getOperatorLoc() &&
9565 // And there is a space or other character before the subexpr of the
9566 // unary +/-. We don't want to warn on "x=-1".
9567 Loc.getLocWithOffset(2) != UO->getSubExpr()->getLocStart() &&
9568 UO->getSubExpr()->getLocStart().isFileID()) {
9569 Diag(Loc, diag::warn_not_compound_assign)
9570 << (UO->getOpcode() == UO_Plus ? "+" : "-")
9571 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc());
9572 }
9573 }
9574
9575 if (ConvTy == Compatible) {
9576 if (LHSType.getObjCLifetime() == Qualifiers::OCL_Strong) {
9577 // Warn about retain cycles where a block captures the LHS, but
9578 // not if the LHS is a simple variable into which the block is
9579 // being stored...unless that variable can be captured by reference!
9580 const Expr *InnerLHS = LHSExpr->IgnoreParenCasts();
9581 const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(InnerLHS);
9582 if (!DRE || DRE->getDecl()->hasAttr<BlocksAttr>())
9583 checkRetainCycles(LHSExpr, RHS.get());
9584
9585 // It is safe to assign a weak reference into a strong variable.
9586 // Although this code can still have problems:
9587 // id x = self.weakProp;
9588 // id y = self.weakProp;
9589 // we do not warn to warn spuriously when 'x' and 'y' are on separate
9590 // paths through the function. This should be revisited if
9591 // -Wrepeated-use-of-weak is made flow-sensitive.
9592 if (!Diags.isIgnored(diag::warn_arc_repeated_use_of_weak,
9593 RHS.get()->getLocStart()))
9594 getCurFunction()->markSafeWeakUse(RHS.get());
9595
9596 } else if (getLangOpts().ObjCAutoRefCount) {
9597 checkUnsafeExprAssigns(Loc, LHSExpr, RHS.get());
9598 }
9599 }
9600 } else {
9601 // Compound assignment "x += y"
9602 ConvTy = CheckAssignmentConstraints(Loc, LHSType, RHSType);
9603 }
9604
9605 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType,
9606 RHS.get(), AA_Assigning))
9607 return QualType();
9608
9609 CheckForNullPointerDereference(*this, LHSExpr);
9610
9611 // C99 6.5.16p3: The type of an assignment expression is the type of the
9612 // left operand unless the left operand has qualified type, in which case
9613 // it is the unqualified version of the type of the left operand.
9614 // C99 6.5.16.1p2: In simple assignment, the value of the right operand
9615 // is converted to the type of the assignment expression (above).
9616 // C++ 5.17p1: the type of the assignment expression is that of its left
9617 // operand.
9618 return (getLangOpts().CPlusPlus
9619 ? LHSType : LHSType.getUnqualifiedType());
9620 }
9621
9622 // C99 6.5.17
CheckCommaOperands(Sema & S,ExprResult & LHS,ExprResult & RHS,SourceLocation Loc)9623 static QualType CheckCommaOperands(Sema &S, ExprResult &LHS, ExprResult &RHS,
9624 SourceLocation Loc) {
9625 LHS = S.CheckPlaceholderExpr(LHS.get());
9626 RHS = S.CheckPlaceholderExpr(RHS.get());
9627 if (LHS.isInvalid() || RHS.isInvalid())
9628 return QualType();
9629
9630 // C's comma performs lvalue conversion (C99 6.3.2.1) on both its
9631 // operands, but not unary promotions.
9632 // C++'s comma does not do any conversions at all (C++ [expr.comma]p1).
9633
9634 // So we treat the LHS as a ignored value, and in C++ we allow the
9635 // containing site to determine what should be done with the RHS.
9636 LHS = S.IgnoredValueConversions(LHS.get());
9637 if (LHS.isInvalid())
9638 return QualType();
9639
9640 S.DiagnoseUnusedExprResult(LHS.get());
9641
9642 if (!S.getLangOpts().CPlusPlus) {
9643 RHS = S.DefaultFunctionArrayLvalueConversion(RHS.get());
9644 if (RHS.isInvalid())
9645 return QualType();
9646 if (!RHS.get()->getType()->isVoidType())
9647 S.RequireCompleteType(Loc, RHS.get()->getType(),
9648 diag::err_incomplete_type);
9649 }
9650
9651 return RHS.get()->getType();
9652 }
9653
9654 /// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine
9655 /// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions.
CheckIncrementDecrementOperand(Sema & S,Expr * Op,ExprValueKind & VK,ExprObjectKind & OK,SourceLocation OpLoc,bool IsInc,bool IsPrefix)9656 static QualType CheckIncrementDecrementOperand(Sema &S, Expr *Op,
9657 ExprValueKind &VK,
9658 ExprObjectKind &OK,
9659 SourceLocation OpLoc,
9660 bool IsInc, bool IsPrefix) {
9661 if (Op->isTypeDependent())
9662 return S.Context.DependentTy;
9663
9664 QualType ResType = Op->getType();
9665 // Atomic types can be used for increment / decrement where the non-atomic
9666 // versions can, so ignore the _Atomic() specifier for the purpose of
9667 // checking.
9668 if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>())
9669 ResType = ResAtomicType->getValueType();
9670
9671 assert(!ResType.isNull() && "no type for increment/decrement expression");
9672
9673 if (S.getLangOpts().CPlusPlus && ResType->isBooleanType()) {
9674 // Decrement of bool is not allowed.
9675 if (!IsInc) {
9676 S.Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange();
9677 return QualType();
9678 }
9679 // Increment of bool sets it to true, but is deprecated.
9680 S.Diag(OpLoc, S.getLangOpts().CPlusPlus1z ? diag::ext_increment_bool
9681 : diag::warn_increment_bool)
9682 << Op->getSourceRange();
9683 } else if (S.getLangOpts().CPlusPlus && ResType->isEnumeralType()) {
9684 // Error on enum increments and decrements in C++ mode
9685 S.Diag(OpLoc, diag::err_increment_decrement_enum) << IsInc << ResType;
9686 return QualType();
9687 } else if (ResType->isRealType()) {
9688 // OK!
9689 } else if (ResType->isPointerType()) {
9690 // C99 6.5.2.4p2, 6.5.6p2
9691 if (!checkArithmeticOpPointerOperand(S, OpLoc, Op))
9692 return QualType();
9693 } else if (ResType->isObjCObjectPointerType()) {
9694 // On modern runtimes, ObjC pointer arithmetic is forbidden.
9695 // Otherwise, we just need a complete type.
9696 if (checkArithmeticIncompletePointerType(S, OpLoc, Op) ||
9697 checkArithmeticOnObjCPointer(S, OpLoc, Op))
9698 return QualType();
9699 } else if (ResType->isAnyComplexType()) {
9700 // C99 does not support ++/-- on complex types, we allow as an extension.
9701 S.Diag(OpLoc, diag::ext_integer_increment_complex)
9702 << ResType << Op->getSourceRange();
9703 } else if (ResType->isPlaceholderType()) {
9704 ExprResult PR = S.CheckPlaceholderExpr(Op);
9705 if (PR.isInvalid()) return QualType();
9706 return CheckIncrementDecrementOperand(S, PR.get(), VK, OK, OpLoc,
9707 IsInc, IsPrefix);
9708 } else if (S.getLangOpts().AltiVec && ResType->isVectorType()) {
9709 // OK! ( C/C++ Language Extensions for CBEA(Version 2.6) 10.3 )
9710 } else if (S.getLangOpts().ZVector && ResType->isVectorType() &&
9711 (ResType->getAs<VectorType>()->getVectorKind() !=
9712 VectorType::AltiVecBool)) {
9713 // The z vector extensions allow ++ and -- for non-bool vectors.
9714 } else if(S.getLangOpts().OpenCL && ResType->isVectorType() &&
9715 ResType->getAs<VectorType>()->getElementType()->isIntegerType()) {
9716 // OpenCL V1.2 6.3 says dec/inc ops operate on integer vector types.
9717 } else {
9718 S.Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement)
9719 << ResType << int(IsInc) << Op->getSourceRange();
9720 return QualType();
9721 }
9722 // At this point, we know we have a real, complex or pointer type.
9723 // Now make sure the operand is a modifiable lvalue.
9724 if (CheckForModifiableLvalue(Op, OpLoc, S))
9725 return QualType();
9726 // In C++, a prefix increment is the same type as the operand. Otherwise
9727 // (in C or with postfix), the increment is the unqualified type of the
9728 // operand.
9729 if (IsPrefix && S.getLangOpts().CPlusPlus) {
9730 VK = VK_LValue;
9731 OK = Op->getObjectKind();
9732 return ResType;
9733 } else {
9734 VK = VK_RValue;
9735 return ResType.getUnqualifiedType();
9736 }
9737 }
9738
9739
9740 /// getPrimaryDecl - Helper function for CheckAddressOfOperand().
9741 /// This routine allows us to typecheck complex/recursive expressions
9742 /// where the declaration is needed for type checking. We only need to
9743 /// handle cases when the expression references a function designator
9744 /// or is an lvalue. Here are some examples:
9745 /// - &(x) => x
9746 /// - &*****f => f for f a function designator.
9747 /// - &s.xx => s
9748 /// - &s.zz[1].yy -> s, if zz is an array
9749 /// - *(x + 1) -> x, if x is an array
9750 /// - &"123"[2] -> 0
9751 /// - & __real__ x -> x
getPrimaryDecl(Expr * E)9752 static ValueDecl *getPrimaryDecl(Expr *E) {
9753 switch (E->getStmtClass()) {
9754 case Stmt::DeclRefExprClass:
9755 return cast<DeclRefExpr>(E)->getDecl();
9756 case Stmt::MemberExprClass:
9757 // If this is an arrow operator, the address is an offset from
9758 // the base's value, so the object the base refers to is
9759 // irrelevant.
9760 if (cast<MemberExpr>(E)->isArrow())
9761 return nullptr;
9762 // Otherwise, the expression refers to a part of the base
9763 return getPrimaryDecl(cast<MemberExpr>(E)->getBase());
9764 case Stmt::ArraySubscriptExprClass: {
9765 // FIXME: This code shouldn't be necessary! We should catch the implicit
9766 // promotion of register arrays earlier.
9767 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase();
9768 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) {
9769 if (ICE->getSubExpr()->getType()->isArrayType())
9770 return getPrimaryDecl(ICE->getSubExpr());
9771 }
9772 return nullptr;
9773 }
9774 case Stmt::UnaryOperatorClass: {
9775 UnaryOperator *UO = cast<UnaryOperator>(E);
9776
9777 switch(UO->getOpcode()) {
9778 case UO_Real:
9779 case UO_Imag:
9780 case UO_Extension:
9781 return getPrimaryDecl(UO->getSubExpr());
9782 default:
9783 return nullptr;
9784 }
9785 }
9786 case Stmt::ParenExprClass:
9787 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr());
9788 case Stmt::ImplicitCastExprClass:
9789 // If the result of an implicit cast is an l-value, we care about
9790 // the sub-expression; otherwise, the result here doesn't matter.
9791 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr());
9792 default:
9793 return nullptr;
9794 }
9795 }
9796
9797 namespace {
9798 enum {
9799 AO_Bit_Field = 0,
9800 AO_Vector_Element = 1,
9801 AO_Property_Expansion = 2,
9802 AO_Register_Variable = 3,
9803 AO_No_Error = 4
9804 };
9805 }
9806 /// \brief Diagnose invalid operand for address of operations.
9807 ///
9808 /// \param Type The type of operand which cannot have its address taken.
diagnoseAddressOfInvalidType(Sema & S,SourceLocation Loc,Expr * E,unsigned Type)9809 static void diagnoseAddressOfInvalidType(Sema &S, SourceLocation Loc,
9810 Expr *E, unsigned Type) {
9811 S.Diag(Loc, diag::err_typecheck_address_of) << Type << E->getSourceRange();
9812 }
9813
9814 /// CheckAddressOfOperand - The operand of & must be either a function
9815 /// designator or an lvalue designating an object. If it is an lvalue, the
9816 /// object cannot be declared with storage class register or be a bit field.
9817 /// Note: The usual conversions are *not* applied to the operand of the &
9818 /// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue.
9819 /// In C++, the operand might be an overloaded function name, in which case
9820 /// we allow the '&' but retain the overloaded-function type.
CheckAddressOfOperand(ExprResult & OrigOp,SourceLocation OpLoc)9821 QualType Sema::CheckAddressOfOperand(ExprResult &OrigOp, SourceLocation OpLoc) {
9822 if (const BuiltinType *PTy = OrigOp.get()->getType()->getAsPlaceholderType()){
9823 if (PTy->getKind() == BuiltinType::Overload) {
9824 Expr *E = OrigOp.get()->IgnoreParens();
9825 if (!isa<OverloadExpr>(E)) {
9826 assert(cast<UnaryOperator>(E)->getOpcode() == UO_AddrOf);
9827 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof_addrof_function)
9828 << OrigOp.get()->getSourceRange();
9829 return QualType();
9830 }
9831
9832 OverloadExpr *Ovl = cast<OverloadExpr>(E);
9833 if (isa<UnresolvedMemberExpr>(Ovl))
9834 if (!ResolveSingleFunctionTemplateSpecialization(Ovl)) {
9835 Diag(OpLoc, diag::err_invalid_form_pointer_member_function)
9836 << OrigOp.get()->getSourceRange();
9837 return QualType();
9838 }
9839
9840 return Context.OverloadTy;
9841 }
9842
9843 if (PTy->getKind() == BuiltinType::UnknownAny)
9844 return Context.UnknownAnyTy;
9845
9846 if (PTy->getKind() == BuiltinType::BoundMember) {
9847 Diag(OpLoc, diag::err_invalid_form_pointer_member_function)
9848 << OrigOp.get()->getSourceRange();
9849 return QualType();
9850 }
9851
9852 OrigOp = CheckPlaceholderExpr(OrigOp.get());
9853 if (OrigOp.isInvalid()) return QualType();
9854 }
9855
9856 if (OrigOp.get()->isTypeDependent())
9857 return Context.DependentTy;
9858
9859 assert(!OrigOp.get()->getType()->isPlaceholderType());
9860
9861 // Make sure to ignore parentheses in subsequent checks
9862 Expr *op = OrigOp.get()->IgnoreParens();
9863
9864 // OpenCL v1.0 s6.8.a.3: Pointers to functions are not allowed.
9865 if (LangOpts.OpenCL && op->getType()->isFunctionType()) {
9866 Diag(op->getExprLoc(), diag::err_opencl_taking_function_address);
9867 return QualType();
9868 }
9869
9870 if (getLangOpts().C99) {
9871 // Implement C99-only parts of addressof rules.
9872 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) {
9873 if (uOp->getOpcode() == UO_Deref)
9874 // Per C99 6.5.3.2, the address of a deref always returns a valid result
9875 // (assuming the deref expression is valid).
9876 return uOp->getSubExpr()->getType();
9877 }
9878 // Technically, there should be a check for array subscript
9879 // expressions here, but the result of one is always an lvalue anyway.
9880 }
9881 ValueDecl *dcl = getPrimaryDecl(op);
9882
9883 if (auto *FD = dyn_cast_or_null<FunctionDecl>(dcl))
9884 if (!checkAddressOfFunctionIsAvailable(FD, /*Complain=*/true,
9885 op->getLocStart()))
9886 return QualType();
9887
9888 Expr::LValueClassification lval = op->ClassifyLValue(Context);
9889 unsigned AddressOfError = AO_No_Error;
9890
9891 if (lval == Expr::LV_ClassTemporary || lval == Expr::LV_ArrayTemporary) {
9892 bool sfinae = (bool)isSFINAEContext();
9893 Diag(OpLoc, isSFINAEContext() ? diag::err_typecheck_addrof_temporary
9894 : diag::ext_typecheck_addrof_temporary)
9895 << op->getType() << op->getSourceRange();
9896 if (sfinae)
9897 return QualType();
9898 // Materialize the temporary as an lvalue so that we can take its address.
9899 OrigOp = op = new (Context)
9900 MaterializeTemporaryExpr(op->getType(), OrigOp.get(), true);
9901 } else if (isa<ObjCSelectorExpr>(op)) {
9902 return Context.getPointerType(op->getType());
9903 } else if (lval == Expr::LV_MemberFunction) {
9904 // If it's an instance method, make a member pointer.
9905 // The expression must have exactly the form &A::foo.
9906
9907 // If the underlying expression isn't a decl ref, give up.
9908 if (!isa<DeclRefExpr>(op)) {
9909 Diag(OpLoc, diag::err_invalid_form_pointer_member_function)
9910 << OrigOp.get()->getSourceRange();
9911 return QualType();
9912 }
9913 DeclRefExpr *DRE = cast<DeclRefExpr>(op);
9914 CXXMethodDecl *MD = cast<CXXMethodDecl>(DRE->getDecl());
9915
9916 // The id-expression was parenthesized.
9917 if (OrigOp.get() != DRE) {
9918 Diag(OpLoc, diag::err_parens_pointer_member_function)
9919 << OrigOp.get()->getSourceRange();
9920
9921 // The method was named without a qualifier.
9922 } else if (!DRE->getQualifier()) {
9923 if (MD->getParent()->getName().empty())
9924 Diag(OpLoc, diag::err_unqualified_pointer_member_function)
9925 << op->getSourceRange();
9926 else {
9927 SmallString<32> Str;
9928 StringRef Qual = (MD->getParent()->getName() + "::").toStringRef(Str);
9929 Diag(OpLoc, diag::err_unqualified_pointer_member_function)
9930 << op->getSourceRange()
9931 << FixItHint::CreateInsertion(op->getSourceRange().getBegin(), Qual);
9932 }
9933 }
9934
9935 // Taking the address of a dtor is illegal per C++ [class.dtor]p2.
9936 if (isa<CXXDestructorDecl>(MD))
9937 Diag(OpLoc, diag::err_typecheck_addrof_dtor) << op->getSourceRange();
9938
9939 QualType MPTy = Context.getMemberPointerType(
9940 op->getType(), Context.getTypeDeclType(MD->getParent()).getTypePtr());
9941 // Under the MS ABI, lock down the inheritance model now.
9942 if (Context.getTargetInfo().getCXXABI().isMicrosoft())
9943 (void)isCompleteType(OpLoc, MPTy);
9944 return MPTy;
9945 } else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) {
9946 // C99 6.5.3.2p1
9947 // The operand must be either an l-value or a function designator
9948 if (!op->getType()->isFunctionType()) {
9949 // Use a special diagnostic for loads from property references.
9950 if (isa<PseudoObjectExpr>(op)) {
9951 AddressOfError = AO_Property_Expansion;
9952 } else {
9953 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof)
9954 << op->getType() << op->getSourceRange();
9955 return QualType();
9956 }
9957 }
9958 } else if (op->getObjectKind() == OK_BitField) { // C99 6.5.3.2p1
9959 // The operand cannot be a bit-field
9960 AddressOfError = AO_Bit_Field;
9961 } else if (op->getObjectKind() == OK_VectorComponent) {
9962 // The operand cannot be an element of a vector
9963 AddressOfError = AO_Vector_Element;
9964 } else if (dcl) { // C99 6.5.3.2p1
9965 // We have an lvalue with a decl. Make sure the decl is not declared
9966 // with the register storage-class specifier.
9967 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) {
9968 // in C++ it is not error to take address of a register
9969 // variable (c++03 7.1.1P3)
9970 if (vd->getStorageClass() == SC_Register &&
9971 !getLangOpts().CPlusPlus) {
9972 AddressOfError = AO_Register_Variable;
9973 }
9974 } else if (isa<MSPropertyDecl>(dcl)) {
9975 AddressOfError = AO_Property_Expansion;
9976 } else if (isa<FunctionTemplateDecl>(dcl)) {
9977 return Context.OverloadTy;
9978 } else if (isa<FieldDecl>(dcl) || isa<IndirectFieldDecl>(dcl)) {
9979 // Okay: we can take the address of a field.
9980 // Could be a pointer to member, though, if there is an explicit
9981 // scope qualifier for the class.
9982 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) {
9983 DeclContext *Ctx = dcl->getDeclContext();
9984 if (Ctx && Ctx->isRecord()) {
9985 if (dcl->getType()->isReferenceType()) {
9986 Diag(OpLoc,
9987 diag::err_cannot_form_pointer_to_member_of_reference_type)
9988 << dcl->getDeclName() << dcl->getType();
9989 return QualType();
9990 }
9991
9992 while (cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion())
9993 Ctx = Ctx->getParent();
9994
9995 QualType MPTy = Context.getMemberPointerType(
9996 op->getType(),
9997 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr());
9998 // Under the MS ABI, lock down the inheritance model now.
9999 if (Context.getTargetInfo().getCXXABI().isMicrosoft())
10000 (void)isCompleteType(OpLoc, MPTy);
10001 return MPTy;
10002 }
10003 }
10004 } else if (!isa<FunctionDecl>(dcl) && !isa<NonTypeTemplateParmDecl>(dcl))
10005 llvm_unreachable("Unknown/unexpected decl type");
10006 }
10007
10008 if (AddressOfError != AO_No_Error) {
10009 diagnoseAddressOfInvalidType(*this, OpLoc, op, AddressOfError);
10010 return QualType();
10011 }
10012
10013 if (lval == Expr::LV_IncompleteVoidType) {
10014 // Taking the address of a void variable is technically illegal, but we
10015 // allow it in cases which are otherwise valid.
10016 // Example: "extern void x; void* y = &x;".
10017 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange();
10018 }
10019
10020 // If the operand has type "type", the result has type "pointer to type".
10021 if (op->getType()->isObjCObjectType())
10022 return Context.getObjCObjectPointerType(op->getType());
10023 return Context.getPointerType(op->getType());
10024 }
10025
RecordModifiableNonNullParam(Sema & S,const Expr * Exp)10026 static void RecordModifiableNonNullParam(Sema &S, const Expr *Exp) {
10027 const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Exp);
10028 if (!DRE)
10029 return;
10030 const Decl *D = DRE->getDecl();
10031 if (!D)
10032 return;
10033 const ParmVarDecl *Param = dyn_cast<ParmVarDecl>(D);
10034 if (!Param)
10035 return;
10036 if (const FunctionDecl* FD = dyn_cast<FunctionDecl>(Param->getDeclContext()))
10037 if (!FD->hasAttr<NonNullAttr>() && !Param->hasAttr<NonNullAttr>())
10038 return;
10039 if (FunctionScopeInfo *FD = S.getCurFunction())
10040 if (!FD->ModifiedNonNullParams.count(Param))
10041 FD->ModifiedNonNullParams.insert(Param);
10042 }
10043
10044 /// CheckIndirectionOperand - Type check unary indirection (prefix '*').
CheckIndirectionOperand(Sema & S,Expr * Op,ExprValueKind & VK,SourceLocation OpLoc)10045 static QualType CheckIndirectionOperand(Sema &S, Expr *Op, ExprValueKind &VK,
10046 SourceLocation OpLoc) {
10047 if (Op->isTypeDependent())
10048 return S.Context.DependentTy;
10049
10050 ExprResult ConvResult = S.UsualUnaryConversions(Op);
10051 if (ConvResult.isInvalid())
10052 return QualType();
10053 Op = ConvResult.get();
10054 QualType OpTy = Op->getType();
10055 QualType Result;
10056
10057 if (isa<CXXReinterpretCastExpr>(Op)) {
10058 QualType OpOrigType = Op->IgnoreParenCasts()->getType();
10059 S.CheckCompatibleReinterpretCast(OpOrigType, OpTy, /*IsDereference*/true,
10060 Op->getSourceRange());
10061 }
10062
10063 if (const PointerType *PT = OpTy->getAs<PointerType>())
10064 Result = PT->getPointeeType();
10065 else if (const ObjCObjectPointerType *OPT =
10066 OpTy->getAs<ObjCObjectPointerType>())
10067 Result = OPT->getPointeeType();
10068 else {
10069 ExprResult PR = S.CheckPlaceholderExpr(Op);
10070 if (PR.isInvalid()) return QualType();
10071 if (PR.get() != Op)
10072 return CheckIndirectionOperand(S, PR.get(), VK, OpLoc);
10073 }
10074
10075 if (Result.isNull()) {
10076 S.Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer)
10077 << OpTy << Op->getSourceRange();
10078 return QualType();
10079 }
10080
10081 // Note that per both C89 and C99, indirection is always legal, even if Result
10082 // is an incomplete type or void. It would be possible to warn about
10083 // dereferencing a void pointer, but it's completely well-defined, and such a
10084 // warning is unlikely to catch any mistakes. In C++, indirection is not valid
10085 // for pointers to 'void' but is fine for any other pointer type:
10086 //
10087 // C++ [expr.unary.op]p1:
10088 // [...] the expression to which [the unary * operator] is applied shall
10089 // be a pointer to an object type, or a pointer to a function type
10090 if (S.getLangOpts().CPlusPlus && Result->isVoidType())
10091 S.Diag(OpLoc, diag::ext_typecheck_indirection_through_void_pointer)
10092 << OpTy << Op->getSourceRange();
10093
10094 // Dereferences are usually l-values...
10095 VK = VK_LValue;
10096
10097 // ...except that certain expressions are never l-values in C.
10098 if (!S.getLangOpts().CPlusPlus && Result.isCForbiddenLValueType())
10099 VK = VK_RValue;
10100
10101 return Result;
10102 }
10103
ConvertTokenKindToBinaryOpcode(tok::TokenKind Kind)10104 BinaryOperatorKind Sema::ConvertTokenKindToBinaryOpcode(tok::TokenKind Kind) {
10105 BinaryOperatorKind Opc;
10106 switch (Kind) {
10107 default: llvm_unreachable("Unknown binop!");
10108 case tok::periodstar: Opc = BO_PtrMemD; break;
10109 case tok::arrowstar: Opc = BO_PtrMemI; break;
10110 case tok::star: Opc = BO_Mul; break;
10111 case tok::slash: Opc = BO_Div; break;
10112 case tok::percent: Opc = BO_Rem; break;
10113 case tok::plus: Opc = BO_Add; break;
10114 case tok::minus: Opc = BO_Sub; break;
10115 case tok::lessless: Opc = BO_Shl; break;
10116 case tok::greatergreater: Opc = BO_Shr; break;
10117 case tok::lessequal: Opc = BO_LE; break;
10118 case tok::less: Opc = BO_LT; break;
10119 case tok::greaterequal: Opc = BO_GE; break;
10120 case tok::greater: Opc = BO_GT; break;
10121 case tok::exclaimequal: Opc = BO_NE; break;
10122 case tok::equalequal: Opc = BO_EQ; break;
10123 case tok::amp: Opc = BO_And; break;
10124 case tok::caret: Opc = BO_Xor; break;
10125 case tok::pipe: Opc = BO_Or; break;
10126 case tok::ampamp: Opc = BO_LAnd; break;
10127 case tok::pipepipe: Opc = BO_LOr; break;
10128 case tok::equal: Opc = BO_Assign; break;
10129 case tok::starequal: Opc = BO_MulAssign; break;
10130 case tok::slashequal: Opc = BO_DivAssign; break;
10131 case tok::percentequal: Opc = BO_RemAssign; break;
10132 case tok::plusequal: Opc = BO_AddAssign; break;
10133 case tok::minusequal: Opc = BO_SubAssign; break;
10134 case tok::lesslessequal: Opc = BO_ShlAssign; break;
10135 case tok::greatergreaterequal: Opc = BO_ShrAssign; break;
10136 case tok::ampequal: Opc = BO_AndAssign; break;
10137 case tok::caretequal: Opc = BO_XorAssign; break;
10138 case tok::pipeequal: Opc = BO_OrAssign; break;
10139 case tok::comma: Opc = BO_Comma; break;
10140 }
10141 return Opc;
10142 }
10143
ConvertTokenKindToUnaryOpcode(tok::TokenKind Kind)10144 static inline UnaryOperatorKind ConvertTokenKindToUnaryOpcode(
10145 tok::TokenKind Kind) {
10146 UnaryOperatorKind Opc;
10147 switch (Kind) {
10148 default: llvm_unreachable("Unknown unary op!");
10149 case tok::plusplus: Opc = UO_PreInc; break;
10150 case tok::minusminus: Opc = UO_PreDec; break;
10151 case tok::amp: Opc = UO_AddrOf; break;
10152 case tok::star: Opc = UO_Deref; break;
10153 case tok::plus: Opc = UO_Plus; break;
10154 case tok::minus: Opc = UO_Minus; break;
10155 case tok::tilde: Opc = UO_Not; break;
10156 case tok::exclaim: Opc = UO_LNot; break;
10157 case tok::kw___real: Opc = UO_Real; break;
10158 case tok::kw___imag: Opc = UO_Imag; break;
10159 case tok::kw___extension__: Opc = UO_Extension; break;
10160 }
10161 return Opc;
10162 }
10163
10164 /// DiagnoseSelfAssignment - Emits a warning if a value is assigned to itself.
10165 /// This warning is only emitted for builtin assignment operations. It is also
10166 /// suppressed in the event of macro expansions.
DiagnoseSelfAssignment(Sema & S,Expr * LHSExpr,Expr * RHSExpr,SourceLocation OpLoc)10167 static void DiagnoseSelfAssignment(Sema &S, Expr *LHSExpr, Expr *RHSExpr,
10168 SourceLocation OpLoc) {
10169 if (!S.ActiveTemplateInstantiations.empty())
10170 return;
10171 if (OpLoc.isInvalid() || OpLoc.isMacroID())
10172 return;
10173 LHSExpr = LHSExpr->IgnoreParenImpCasts();
10174 RHSExpr = RHSExpr->IgnoreParenImpCasts();
10175 const DeclRefExpr *LHSDeclRef = dyn_cast<DeclRefExpr>(LHSExpr);
10176 const DeclRefExpr *RHSDeclRef = dyn_cast<DeclRefExpr>(RHSExpr);
10177 if (!LHSDeclRef || !RHSDeclRef ||
10178 LHSDeclRef->getLocation().isMacroID() ||
10179 RHSDeclRef->getLocation().isMacroID())
10180 return;
10181 const ValueDecl *LHSDecl =
10182 cast<ValueDecl>(LHSDeclRef->getDecl()->getCanonicalDecl());
10183 const ValueDecl *RHSDecl =
10184 cast<ValueDecl>(RHSDeclRef->getDecl()->getCanonicalDecl());
10185 if (LHSDecl != RHSDecl)
10186 return;
10187 if (LHSDecl->getType().isVolatileQualified())
10188 return;
10189 if (const ReferenceType *RefTy = LHSDecl->getType()->getAs<ReferenceType>())
10190 if (RefTy->getPointeeType().isVolatileQualified())
10191 return;
10192
10193 S.Diag(OpLoc, diag::warn_self_assignment)
10194 << LHSDeclRef->getType()
10195 << LHSExpr->getSourceRange() << RHSExpr->getSourceRange();
10196 }
10197
10198 /// Check if a bitwise-& is performed on an Objective-C pointer. This
10199 /// is usually indicative of introspection within the Objective-C pointer.
checkObjCPointerIntrospection(Sema & S,ExprResult & L,ExprResult & R,SourceLocation OpLoc)10200 static void checkObjCPointerIntrospection(Sema &S, ExprResult &L, ExprResult &R,
10201 SourceLocation OpLoc) {
10202 if (!S.getLangOpts().ObjC1)
10203 return;
10204
10205 const Expr *ObjCPointerExpr = nullptr, *OtherExpr = nullptr;
10206 const Expr *LHS = L.get();
10207 const Expr *RHS = R.get();
10208
10209 if (LHS->IgnoreParenCasts()->getType()->isObjCObjectPointerType()) {
10210 ObjCPointerExpr = LHS;
10211 OtherExpr = RHS;
10212 }
10213 else if (RHS->IgnoreParenCasts()->getType()->isObjCObjectPointerType()) {
10214 ObjCPointerExpr = RHS;
10215 OtherExpr = LHS;
10216 }
10217
10218 // This warning is deliberately made very specific to reduce false
10219 // positives with logic that uses '&' for hashing. This logic mainly
10220 // looks for code trying to introspect into tagged pointers, which
10221 // code should generally never do.
10222 if (ObjCPointerExpr && isa<IntegerLiteral>(OtherExpr->IgnoreParenCasts())) {
10223 unsigned Diag = diag::warn_objc_pointer_masking;
10224 // Determine if we are introspecting the result of performSelectorXXX.
10225 const Expr *Ex = ObjCPointerExpr->IgnoreParenCasts();
10226 // Special case messages to -performSelector and friends, which
10227 // can return non-pointer values boxed in a pointer value.
10228 // Some clients may wish to silence warnings in this subcase.
10229 if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(Ex)) {
10230 Selector S = ME->getSelector();
10231 StringRef SelArg0 = S.getNameForSlot(0);
10232 if (SelArg0.startswith("performSelector"))
10233 Diag = diag::warn_objc_pointer_masking_performSelector;
10234 }
10235
10236 S.Diag(OpLoc, Diag)
10237 << ObjCPointerExpr->getSourceRange();
10238 }
10239 }
10240
getDeclFromExpr(Expr * E)10241 static NamedDecl *getDeclFromExpr(Expr *E) {
10242 if (!E)
10243 return nullptr;
10244 if (auto *DRE = dyn_cast<DeclRefExpr>(E))
10245 return DRE->getDecl();
10246 if (auto *ME = dyn_cast<MemberExpr>(E))
10247 return ME->getMemberDecl();
10248 if (auto *IRE = dyn_cast<ObjCIvarRefExpr>(E))
10249 return IRE->getDecl();
10250 return nullptr;
10251 }
10252
10253 /// CreateBuiltinBinOp - Creates a new built-in binary operation with
10254 /// operator @p Opc at location @c TokLoc. This routine only supports
10255 /// built-in operations; ActOnBinOp handles overloaded operators.
CreateBuiltinBinOp(SourceLocation OpLoc,BinaryOperatorKind Opc,Expr * LHSExpr,Expr * RHSExpr)10256 ExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc,
10257 BinaryOperatorKind Opc,
10258 Expr *LHSExpr, Expr *RHSExpr) {
10259 if (getLangOpts().CPlusPlus11 && isa<InitListExpr>(RHSExpr)) {
10260 // The syntax only allows initializer lists on the RHS of assignment,
10261 // so we don't need to worry about accepting invalid code for
10262 // non-assignment operators.
10263 // C++11 5.17p9:
10264 // The meaning of x = {v} [...] is that of x = T(v) [...]. The meaning
10265 // of x = {} is x = T().
10266 InitializationKind Kind =
10267 InitializationKind::CreateDirectList(RHSExpr->getLocStart());
10268 InitializedEntity Entity =
10269 InitializedEntity::InitializeTemporary(LHSExpr->getType());
10270 InitializationSequence InitSeq(*this, Entity, Kind, RHSExpr);
10271 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, RHSExpr);
10272 if (Init.isInvalid())
10273 return Init;
10274 RHSExpr = Init.get();
10275 }
10276
10277 ExprResult LHS = LHSExpr, RHS = RHSExpr;
10278 QualType ResultTy; // Result type of the binary operator.
10279 // The following two variables are used for compound assignment operators
10280 QualType CompLHSTy; // Type of LHS after promotions for computation
10281 QualType CompResultTy; // Type of computation result
10282 ExprValueKind VK = VK_RValue;
10283 ExprObjectKind OK = OK_Ordinary;
10284
10285 if (!getLangOpts().CPlusPlus) {
10286 // C cannot handle TypoExpr nodes on either side of a binop because it
10287 // doesn't handle dependent types properly, so make sure any TypoExprs have
10288 // been dealt with before checking the operands.
10289 LHS = CorrectDelayedTyposInExpr(LHSExpr);
10290 RHS = CorrectDelayedTyposInExpr(RHSExpr, [Opc, LHS](Expr *E) {
10291 if (Opc != BO_Assign)
10292 return ExprResult(E);
10293 // Avoid correcting the RHS to the same Expr as the LHS.
10294 Decl *D = getDeclFromExpr(E);
10295 return (D && D == getDeclFromExpr(LHS.get())) ? ExprError() : E;
10296 });
10297 if (!LHS.isUsable() || !RHS.isUsable())
10298 return ExprError();
10299 }
10300
10301 if (getLangOpts().OpenCL) {
10302 // OpenCLC v2.0 s6.13.11.1 allows atomic variables to be initialized by
10303 // the ATOMIC_VAR_INIT macro.
10304 if (LHSExpr->getType()->isAtomicType() ||
10305 RHSExpr->getType()->isAtomicType()) {
10306 SourceRange SR(LHSExpr->getLocStart(), RHSExpr->getLocEnd());
10307 if (BO_Assign == Opc)
10308 Diag(OpLoc, diag::err_atomic_init_constant) << SR;
10309 else
10310 ResultTy = InvalidOperands(OpLoc, LHS, RHS);
10311 return ExprError();
10312 }
10313 }
10314
10315 switch (Opc) {
10316 case BO_Assign:
10317 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, QualType());
10318 if (getLangOpts().CPlusPlus &&
10319 LHS.get()->getObjectKind() != OK_ObjCProperty) {
10320 VK = LHS.get()->getValueKind();
10321 OK = LHS.get()->getObjectKind();
10322 }
10323 if (!ResultTy.isNull()) {
10324 DiagnoseSelfAssignment(*this, LHS.get(), RHS.get(), OpLoc);
10325 DiagnoseSelfMove(LHS.get(), RHS.get(), OpLoc);
10326 }
10327 RecordModifiableNonNullParam(*this, LHS.get());
10328 break;
10329 case BO_PtrMemD:
10330 case BO_PtrMemI:
10331 ResultTy = CheckPointerToMemberOperands(LHS, RHS, VK, OpLoc,
10332 Opc == BO_PtrMemI);
10333 break;
10334 case BO_Mul:
10335 case BO_Div:
10336 ResultTy = CheckMultiplyDivideOperands(LHS, RHS, OpLoc, false,
10337 Opc == BO_Div);
10338 break;
10339 case BO_Rem:
10340 ResultTy = CheckRemainderOperands(LHS, RHS, OpLoc);
10341 break;
10342 case BO_Add:
10343 ResultTy = CheckAdditionOperands(LHS, RHS, OpLoc, Opc);
10344 break;
10345 case BO_Sub:
10346 ResultTy = CheckSubtractionOperands(LHS, RHS, OpLoc);
10347 break;
10348 case BO_Shl:
10349 case BO_Shr:
10350 ResultTy = CheckShiftOperands(LHS, RHS, OpLoc, Opc);
10351 break;
10352 case BO_LE:
10353 case BO_LT:
10354 case BO_GE:
10355 case BO_GT:
10356 ResultTy = CheckCompareOperands(LHS, RHS, OpLoc, Opc, true);
10357 break;
10358 case BO_EQ:
10359 case BO_NE:
10360 ResultTy = CheckCompareOperands(LHS, RHS, OpLoc, Opc, false);
10361 break;
10362 case BO_And:
10363 checkObjCPointerIntrospection(*this, LHS, RHS, OpLoc);
10364 case BO_Xor:
10365 case BO_Or:
10366 ResultTy = CheckBitwiseOperands(LHS, RHS, OpLoc);
10367 break;
10368 case BO_LAnd:
10369 case BO_LOr:
10370 ResultTy = CheckLogicalOperands(LHS, RHS, OpLoc, Opc);
10371 break;
10372 case BO_MulAssign:
10373 case BO_DivAssign:
10374 CompResultTy = CheckMultiplyDivideOperands(LHS, RHS, OpLoc, true,
10375 Opc == BO_DivAssign);
10376 CompLHSTy = CompResultTy;
10377 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
10378 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
10379 break;
10380 case BO_RemAssign:
10381 CompResultTy = CheckRemainderOperands(LHS, RHS, OpLoc, true);
10382 CompLHSTy = CompResultTy;
10383 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
10384 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
10385 break;
10386 case BO_AddAssign:
10387 CompResultTy = CheckAdditionOperands(LHS, RHS, OpLoc, Opc, &CompLHSTy);
10388 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
10389 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
10390 break;
10391 case BO_SubAssign:
10392 CompResultTy = CheckSubtractionOperands(LHS, RHS, OpLoc, &CompLHSTy);
10393 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
10394 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
10395 break;
10396 case BO_ShlAssign:
10397 case BO_ShrAssign:
10398 CompResultTy = CheckShiftOperands(LHS, RHS, OpLoc, Opc, true);
10399 CompLHSTy = CompResultTy;
10400 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
10401 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
10402 break;
10403 case BO_AndAssign:
10404 case BO_OrAssign: // fallthrough
10405 DiagnoseSelfAssignment(*this, LHS.get(), RHS.get(), OpLoc);
10406 case BO_XorAssign:
10407 CompResultTy = CheckBitwiseOperands(LHS, RHS, OpLoc, true);
10408 CompLHSTy = CompResultTy;
10409 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
10410 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
10411 break;
10412 case BO_Comma:
10413 ResultTy = CheckCommaOperands(*this, LHS, RHS, OpLoc);
10414 if (getLangOpts().CPlusPlus && !RHS.isInvalid()) {
10415 VK = RHS.get()->getValueKind();
10416 OK = RHS.get()->getObjectKind();
10417 }
10418 break;
10419 }
10420 if (ResultTy.isNull() || LHS.isInvalid() || RHS.isInvalid())
10421 return ExprError();
10422
10423 // Check for array bounds violations for both sides of the BinaryOperator
10424 CheckArrayAccess(LHS.get());
10425 CheckArrayAccess(RHS.get());
10426
10427 if (const ObjCIsaExpr *OISA = dyn_cast<ObjCIsaExpr>(LHS.get()->IgnoreParenCasts())) {
10428 NamedDecl *ObjectSetClass = LookupSingleName(TUScope,
10429 &Context.Idents.get("object_setClass"),
10430 SourceLocation(), LookupOrdinaryName);
10431 if (ObjectSetClass && isa<ObjCIsaExpr>(LHS.get())) {
10432 SourceLocation RHSLocEnd = getLocForEndOfToken(RHS.get()->getLocEnd());
10433 Diag(LHS.get()->getExprLoc(), diag::warn_objc_isa_assign) <<
10434 FixItHint::CreateInsertion(LHS.get()->getLocStart(), "object_setClass(") <<
10435 FixItHint::CreateReplacement(SourceRange(OISA->getOpLoc(), OpLoc), ",") <<
10436 FixItHint::CreateInsertion(RHSLocEnd, ")");
10437 }
10438 else
10439 Diag(LHS.get()->getExprLoc(), diag::warn_objc_isa_assign);
10440 }
10441 else if (const ObjCIvarRefExpr *OIRE =
10442 dyn_cast<ObjCIvarRefExpr>(LHS.get()->IgnoreParenCasts()))
10443 DiagnoseDirectIsaAccess(*this, OIRE, OpLoc, RHS.get());
10444
10445 if (CompResultTy.isNull())
10446 return new (Context) BinaryOperator(LHS.get(), RHS.get(), Opc, ResultTy, VK,
10447 OK, OpLoc, FPFeatures.fp_contract);
10448 if (getLangOpts().CPlusPlus && LHS.get()->getObjectKind() !=
10449 OK_ObjCProperty) {
10450 VK = VK_LValue;
10451 OK = LHS.get()->getObjectKind();
10452 }
10453 return new (Context) CompoundAssignOperator(
10454 LHS.get(), RHS.get(), Opc, ResultTy, VK, OK, CompLHSTy, CompResultTy,
10455 OpLoc, FPFeatures.fp_contract);
10456 }
10457
10458 /// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison
10459 /// operators are mixed in a way that suggests that the programmer forgot that
10460 /// comparison operators have higher precedence. The most typical example of
10461 /// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1".
DiagnoseBitwisePrecedence(Sema & Self,BinaryOperatorKind Opc,SourceLocation OpLoc,Expr * LHSExpr,Expr * RHSExpr)10462 static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperatorKind Opc,
10463 SourceLocation OpLoc, Expr *LHSExpr,
10464 Expr *RHSExpr) {
10465 BinaryOperator *LHSBO = dyn_cast<BinaryOperator>(LHSExpr);
10466 BinaryOperator *RHSBO = dyn_cast<BinaryOperator>(RHSExpr);
10467
10468 // Check that one of the sides is a comparison operator and the other isn't.
10469 bool isLeftComp = LHSBO && LHSBO->isComparisonOp();
10470 bool isRightComp = RHSBO && RHSBO->isComparisonOp();
10471 if (isLeftComp == isRightComp)
10472 return;
10473
10474 // Bitwise operations are sometimes used as eager logical ops.
10475 // Don't diagnose this.
10476 bool isLeftBitwise = LHSBO && LHSBO->isBitwiseOp();
10477 bool isRightBitwise = RHSBO && RHSBO->isBitwiseOp();
10478 if (isLeftBitwise || isRightBitwise)
10479 return;
10480
10481 SourceRange DiagRange = isLeftComp ? SourceRange(LHSExpr->getLocStart(),
10482 OpLoc)
10483 : SourceRange(OpLoc, RHSExpr->getLocEnd());
10484 StringRef OpStr = isLeftComp ? LHSBO->getOpcodeStr() : RHSBO->getOpcodeStr();
10485 SourceRange ParensRange = isLeftComp ?
10486 SourceRange(LHSBO->getRHS()->getLocStart(), RHSExpr->getLocEnd())
10487 : SourceRange(LHSExpr->getLocStart(), RHSBO->getLHS()->getLocEnd());
10488
10489 Self.Diag(OpLoc, diag::warn_precedence_bitwise_rel)
10490 << DiagRange << BinaryOperator::getOpcodeStr(Opc) << OpStr;
10491 SuggestParentheses(Self, OpLoc,
10492 Self.PDiag(diag::note_precedence_silence) << OpStr,
10493 (isLeftComp ? LHSExpr : RHSExpr)->getSourceRange());
10494 SuggestParentheses(Self, OpLoc,
10495 Self.PDiag(diag::note_precedence_bitwise_first)
10496 << BinaryOperator::getOpcodeStr(Opc),
10497 ParensRange);
10498 }
10499
10500 /// \brief It accepts a '&&' expr that is inside a '||' one.
10501 /// Emit a diagnostic together with a fixit hint that wraps the '&&' expression
10502 /// in parentheses.
10503 static void
EmitDiagnosticForLogicalAndInLogicalOr(Sema & Self,SourceLocation OpLoc,BinaryOperator * Bop)10504 EmitDiagnosticForLogicalAndInLogicalOr(Sema &Self, SourceLocation OpLoc,
10505 BinaryOperator *Bop) {
10506 assert(Bop->getOpcode() == BO_LAnd);
10507 Self.Diag(Bop->getOperatorLoc(), diag::warn_logical_and_in_logical_or)
10508 << Bop->getSourceRange() << OpLoc;
10509 SuggestParentheses(Self, Bop->getOperatorLoc(),
10510 Self.PDiag(diag::note_precedence_silence)
10511 << Bop->getOpcodeStr(),
10512 Bop->getSourceRange());
10513 }
10514
10515 /// \brief Returns true if the given expression can be evaluated as a constant
10516 /// 'true'.
EvaluatesAsTrue(Sema & S,Expr * E)10517 static bool EvaluatesAsTrue(Sema &S, Expr *E) {
10518 bool Res;
10519 return !E->isValueDependent() &&
10520 E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && Res;
10521 }
10522
10523 /// \brief Returns true if the given expression can be evaluated as a constant
10524 /// 'false'.
EvaluatesAsFalse(Sema & S,Expr * E)10525 static bool EvaluatesAsFalse(Sema &S, Expr *E) {
10526 bool Res;
10527 return !E->isValueDependent() &&
10528 E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && !Res;
10529 }
10530
10531 /// \brief Look for '&&' in the left hand of a '||' expr.
DiagnoseLogicalAndInLogicalOrLHS(Sema & S,SourceLocation OpLoc,Expr * LHSExpr,Expr * RHSExpr)10532 static void DiagnoseLogicalAndInLogicalOrLHS(Sema &S, SourceLocation OpLoc,
10533 Expr *LHSExpr, Expr *RHSExpr) {
10534 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(LHSExpr)) {
10535 if (Bop->getOpcode() == BO_LAnd) {
10536 // If it's "a && b || 0" don't warn since the precedence doesn't matter.
10537 if (EvaluatesAsFalse(S, RHSExpr))
10538 return;
10539 // If it's "1 && a || b" don't warn since the precedence doesn't matter.
10540 if (!EvaluatesAsTrue(S, Bop->getLHS()))
10541 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop);
10542 } else if (Bop->getOpcode() == BO_LOr) {
10543 if (BinaryOperator *RBop = dyn_cast<BinaryOperator>(Bop->getRHS())) {
10544 // If it's "a || b && 1 || c" we didn't warn earlier for
10545 // "a || b && 1", but warn now.
10546 if (RBop->getOpcode() == BO_LAnd && EvaluatesAsTrue(S, RBop->getRHS()))
10547 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, RBop);
10548 }
10549 }
10550 }
10551 }
10552
10553 /// \brief Look for '&&' in the right hand of a '||' expr.
DiagnoseLogicalAndInLogicalOrRHS(Sema & S,SourceLocation OpLoc,Expr * LHSExpr,Expr * RHSExpr)10554 static void DiagnoseLogicalAndInLogicalOrRHS(Sema &S, SourceLocation OpLoc,
10555 Expr *LHSExpr, Expr *RHSExpr) {
10556 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(RHSExpr)) {
10557 if (Bop->getOpcode() == BO_LAnd) {
10558 // If it's "0 || a && b" don't warn since the precedence doesn't matter.
10559 if (EvaluatesAsFalse(S, LHSExpr))
10560 return;
10561 // If it's "a || b && 1" don't warn since the precedence doesn't matter.
10562 if (!EvaluatesAsTrue(S, Bop->getRHS()))
10563 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop);
10564 }
10565 }
10566 }
10567
10568 /// \brief Look for bitwise op in the left or right hand of a bitwise op with
10569 /// lower precedence and emit a diagnostic together with a fixit hint that wraps
10570 /// the '&' expression in parentheses.
DiagnoseBitwiseOpInBitwiseOp(Sema & S,BinaryOperatorKind Opc,SourceLocation OpLoc,Expr * SubExpr)10571 static void DiagnoseBitwiseOpInBitwiseOp(Sema &S, BinaryOperatorKind Opc,
10572 SourceLocation OpLoc, Expr *SubExpr) {
10573 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(SubExpr)) {
10574 if (Bop->isBitwiseOp() && Bop->getOpcode() < Opc) {
10575 S.Diag(Bop->getOperatorLoc(), diag::warn_bitwise_op_in_bitwise_op)
10576 << Bop->getOpcodeStr() << BinaryOperator::getOpcodeStr(Opc)
10577 << Bop->getSourceRange() << OpLoc;
10578 SuggestParentheses(S, Bop->getOperatorLoc(),
10579 S.PDiag(diag::note_precedence_silence)
10580 << Bop->getOpcodeStr(),
10581 Bop->getSourceRange());
10582 }
10583 }
10584 }
10585
DiagnoseAdditionInShift(Sema & S,SourceLocation OpLoc,Expr * SubExpr,StringRef Shift)10586 static void DiagnoseAdditionInShift(Sema &S, SourceLocation OpLoc,
10587 Expr *SubExpr, StringRef Shift) {
10588 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(SubExpr)) {
10589 if (Bop->getOpcode() == BO_Add || Bop->getOpcode() == BO_Sub) {
10590 StringRef Op = Bop->getOpcodeStr();
10591 S.Diag(Bop->getOperatorLoc(), diag::warn_addition_in_bitshift)
10592 << Bop->getSourceRange() << OpLoc << Shift << Op;
10593 SuggestParentheses(S, Bop->getOperatorLoc(),
10594 S.PDiag(diag::note_precedence_silence) << Op,
10595 Bop->getSourceRange());
10596 }
10597 }
10598 }
10599
DiagnoseShiftCompare(Sema & S,SourceLocation OpLoc,Expr * LHSExpr,Expr * RHSExpr)10600 static void DiagnoseShiftCompare(Sema &S, SourceLocation OpLoc,
10601 Expr *LHSExpr, Expr *RHSExpr) {
10602 CXXOperatorCallExpr *OCE = dyn_cast<CXXOperatorCallExpr>(LHSExpr);
10603 if (!OCE)
10604 return;
10605
10606 FunctionDecl *FD = OCE->getDirectCallee();
10607 if (!FD || !FD->isOverloadedOperator())
10608 return;
10609
10610 OverloadedOperatorKind Kind = FD->getOverloadedOperator();
10611 if (Kind != OO_LessLess && Kind != OO_GreaterGreater)
10612 return;
10613
10614 S.Diag(OpLoc, diag::warn_overloaded_shift_in_comparison)
10615 << LHSExpr->getSourceRange() << RHSExpr->getSourceRange()
10616 << (Kind == OO_LessLess);
10617 SuggestParentheses(S, OCE->getOperatorLoc(),
10618 S.PDiag(diag::note_precedence_silence)
10619 << (Kind == OO_LessLess ? "<<" : ">>"),
10620 OCE->getSourceRange());
10621 SuggestParentheses(S, OpLoc,
10622 S.PDiag(diag::note_evaluate_comparison_first),
10623 SourceRange(OCE->getArg(1)->getLocStart(),
10624 RHSExpr->getLocEnd()));
10625 }
10626
10627 /// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky
10628 /// precedence.
DiagnoseBinOpPrecedence(Sema & Self,BinaryOperatorKind Opc,SourceLocation OpLoc,Expr * LHSExpr,Expr * RHSExpr)10629 static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperatorKind Opc,
10630 SourceLocation OpLoc, Expr *LHSExpr,
10631 Expr *RHSExpr){
10632 // Diagnose "arg1 'bitwise' arg2 'eq' arg3".
10633 if (BinaryOperator::isBitwiseOp(Opc))
10634 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, LHSExpr, RHSExpr);
10635
10636 // Diagnose "arg1 & arg2 | arg3"
10637 if ((Opc == BO_Or || Opc == BO_Xor) &&
10638 !OpLoc.isMacroID()/* Don't warn in macros. */) {
10639 DiagnoseBitwiseOpInBitwiseOp(Self, Opc, OpLoc, LHSExpr);
10640 DiagnoseBitwiseOpInBitwiseOp(Self, Opc, OpLoc, RHSExpr);
10641 }
10642
10643 // Warn about arg1 || arg2 && arg3, as GCC 4.3+ does.
10644 // We don't warn for 'assert(a || b && "bad")' since this is safe.
10645 if (Opc == BO_LOr && !OpLoc.isMacroID()/* Don't warn in macros. */) {
10646 DiagnoseLogicalAndInLogicalOrLHS(Self, OpLoc, LHSExpr, RHSExpr);
10647 DiagnoseLogicalAndInLogicalOrRHS(Self, OpLoc, LHSExpr, RHSExpr);
10648 }
10649
10650 if ((Opc == BO_Shl && LHSExpr->getType()->isIntegralType(Self.getASTContext()))
10651 || Opc == BO_Shr) {
10652 StringRef Shift = BinaryOperator::getOpcodeStr(Opc);
10653 DiagnoseAdditionInShift(Self, OpLoc, LHSExpr, Shift);
10654 DiagnoseAdditionInShift(Self, OpLoc, RHSExpr, Shift);
10655 }
10656
10657 // Warn on overloaded shift operators and comparisons, such as:
10658 // cout << 5 == 4;
10659 if (BinaryOperator::isComparisonOp(Opc))
10660 DiagnoseShiftCompare(Self, OpLoc, LHSExpr, RHSExpr);
10661 }
10662
10663 // Binary Operators. 'Tok' is the token for the operator.
ActOnBinOp(Scope * S,SourceLocation TokLoc,tok::TokenKind Kind,Expr * LHSExpr,Expr * RHSExpr)10664 ExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc,
10665 tok::TokenKind Kind,
10666 Expr *LHSExpr, Expr *RHSExpr) {
10667 BinaryOperatorKind Opc = ConvertTokenKindToBinaryOpcode(Kind);
10668 assert(LHSExpr && "ActOnBinOp(): missing left expression");
10669 assert(RHSExpr && "ActOnBinOp(): missing right expression");
10670
10671 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0"
10672 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, LHSExpr, RHSExpr);
10673
10674 return BuildBinOp(S, TokLoc, Opc, LHSExpr, RHSExpr);
10675 }
10676
10677 /// Build an overloaded binary operator expression in the given scope.
BuildOverloadedBinOp(Sema & S,Scope * Sc,SourceLocation OpLoc,BinaryOperatorKind Opc,Expr * LHS,Expr * RHS)10678 static ExprResult BuildOverloadedBinOp(Sema &S, Scope *Sc, SourceLocation OpLoc,
10679 BinaryOperatorKind Opc,
10680 Expr *LHS, Expr *RHS) {
10681 // Find all of the overloaded operators visible from this
10682 // point. We perform both an operator-name lookup from the local
10683 // scope and an argument-dependent lookup based on the types of
10684 // the arguments.
10685 UnresolvedSet<16> Functions;
10686 OverloadedOperatorKind OverOp
10687 = BinaryOperator::getOverloadedOperator(Opc);
10688 if (Sc && OverOp != OO_None && OverOp != OO_Equal)
10689 S.LookupOverloadedOperatorName(OverOp, Sc, LHS->getType(),
10690 RHS->getType(), Functions);
10691
10692 // Build the (potentially-overloaded, potentially-dependent)
10693 // binary operation.
10694 return S.CreateOverloadedBinOp(OpLoc, Opc, Functions, LHS, RHS);
10695 }
10696
BuildBinOp(Scope * S,SourceLocation OpLoc,BinaryOperatorKind Opc,Expr * LHSExpr,Expr * RHSExpr)10697 ExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc,
10698 BinaryOperatorKind Opc,
10699 Expr *LHSExpr, Expr *RHSExpr) {
10700 // We want to end up calling one of checkPseudoObjectAssignment
10701 // (if the LHS is a pseudo-object), BuildOverloadedBinOp (if
10702 // both expressions are overloadable or either is type-dependent),
10703 // or CreateBuiltinBinOp (in any other case). We also want to get
10704 // any placeholder types out of the way.
10705
10706 // Handle pseudo-objects in the LHS.
10707 if (const BuiltinType *pty = LHSExpr->getType()->getAsPlaceholderType()) {
10708 // Assignments with a pseudo-object l-value need special analysis.
10709 if (pty->getKind() == BuiltinType::PseudoObject &&
10710 BinaryOperator::isAssignmentOp(Opc))
10711 return checkPseudoObjectAssignment(S, OpLoc, Opc, LHSExpr, RHSExpr);
10712
10713 // Don't resolve overloads if the other type is overloadable.
10714 if (pty->getKind() == BuiltinType::Overload) {
10715 // We can't actually test that if we still have a placeholder,
10716 // though. Fortunately, none of the exceptions we see in that
10717 // code below are valid when the LHS is an overload set. Note
10718 // that an overload set can be dependently-typed, but it never
10719 // instantiates to having an overloadable type.
10720 ExprResult resolvedRHS = CheckPlaceholderExpr(RHSExpr);
10721 if (resolvedRHS.isInvalid()) return ExprError();
10722 RHSExpr = resolvedRHS.get();
10723
10724 if (RHSExpr->isTypeDependent() ||
10725 RHSExpr->getType()->isOverloadableType())
10726 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr);
10727 }
10728
10729 ExprResult LHS = CheckPlaceholderExpr(LHSExpr);
10730 if (LHS.isInvalid()) return ExprError();
10731 LHSExpr = LHS.get();
10732 }
10733
10734 // Handle pseudo-objects in the RHS.
10735 if (const BuiltinType *pty = RHSExpr->getType()->getAsPlaceholderType()) {
10736 // An overload in the RHS can potentially be resolved by the type
10737 // being assigned to.
10738 if (Opc == BO_Assign && pty->getKind() == BuiltinType::Overload) {
10739 if (LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent())
10740 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr);
10741
10742 if (LHSExpr->getType()->isOverloadableType())
10743 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr);
10744
10745 return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr);
10746 }
10747
10748 // Don't resolve overloads if the other type is overloadable.
10749 if (pty->getKind() == BuiltinType::Overload &&
10750 LHSExpr->getType()->isOverloadableType())
10751 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr);
10752
10753 ExprResult resolvedRHS = CheckPlaceholderExpr(RHSExpr);
10754 if (!resolvedRHS.isUsable()) return ExprError();
10755 RHSExpr = resolvedRHS.get();
10756 }
10757
10758 if (getLangOpts().CPlusPlus) {
10759 // If either expression is type-dependent, always build an
10760 // overloaded op.
10761 if (LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent())
10762 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr);
10763
10764 // Otherwise, build an overloaded op if either expression has an
10765 // overloadable type.
10766 if (LHSExpr->getType()->isOverloadableType() ||
10767 RHSExpr->getType()->isOverloadableType())
10768 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr);
10769 }
10770
10771 // Build a built-in binary operation.
10772 return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr);
10773 }
10774
CreateBuiltinUnaryOp(SourceLocation OpLoc,UnaryOperatorKind Opc,Expr * InputExpr)10775 ExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc,
10776 UnaryOperatorKind Opc,
10777 Expr *InputExpr) {
10778 ExprResult Input = InputExpr;
10779 ExprValueKind VK = VK_RValue;
10780 ExprObjectKind OK = OK_Ordinary;
10781 QualType resultType;
10782 if (getLangOpts().OpenCL) {
10783 // The only legal unary operation for atomics is '&'.
10784 if (Opc != UO_AddrOf && InputExpr->getType()->isAtomicType()) {
10785 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
10786 << InputExpr->getType()
10787 << Input.get()->getSourceRange());
10788 }
10789 }
10790 switch (Opc) {
10791 case UO_PreInc:
10792 case UO_PreDec:
10793 case UO_PostInc:
10794 case UO_PostDec:
10795 resultType = CheckIncrementDecrementOperand(*this, Input.get(), VK, OK,
10796 OpLoc,
10797 Opc == UO_PreInc ||
10798 Opc == UO_PostInc,
10799 Opc == UO_PreInc ||
10800 Opc == UO_PreDec);
10801 break;
10802 case UO_AddrOf:
10803 resultType = CheckAddressOfOperand(Input, OpLoc);
10804 RecordModifiableNonNullParam(*this, InputExpr);
10805 break;
10806 case UO_Deref: {
10807 Input = DefaultFunctionArrayLvalueConversion(Input.get());
10808 if (Input.isInvalid()) return ExprError();
10809 resultType = CheckIndirectionOperand(*this, Input.get(), VK, OpLoc);
10810 break;
10811 }
10812 case UO_Plus:
10813 case UO_Minus:
10814 Input = UsualUnaryConversions(Input.get());
10815 if (Input.isInvalid()) return ExprError();
10816 resultType = Input.get()->getType();
10817 if (resultType->isDependentType())
10818 break;
10819 if (resultType->isArithmeticType()) // C99 6.5.3.3p1
10820 break;
10821 else if (resultType->isVectorType() &&
10822 // The z vector extensions don't allow + or - with bool vectors.
10823 (!Context.getLangOpts().ZVector ||
10824 resultType->getAs<VectorType>()->getVectorKind() !=
10825 VectorType::AltiVecBool))
10826 break;
10827 else if (getLangOpts().CPlusPlus && // C++ [expr.unary.op]p6
10828 Opc == UO_Plus &&
10829 resultType->isPointerType())
10830 break;
10831
10832 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
10833 << resultType << Input.get()->getSourceRange());
10834
10835 case UO_Not: // bitwise complement
10836 Input = UsualUnaryConversions(Input.get());
10837 if (Input.isInvalid())
10838 return ExprError();
10839 resultType = Input.get()->getType();
10840 if (resultType->isDependentType())
10841 break;
10842 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension.
10843 if (resultType->isComplexType() || resultType->isComplexIntegerType())
10844 // C99 does not support '~' for complex conjugation.
10845 Diag(OpLoc, diag::ext_integer_complement_complex)
10846 << resultType << Input.get()->getSourceRange();
10847 else if (resultType->hasIntegerRepresentation())
10848 break;
10849 else if (resultType->isExtVectorType()) {
10850 if (Context.getLangOpts().OpenCL) {
10851 // OpenCL v1.1 s6.3.f: The bitwise operator not (~) does not operate
10852 // on vector float types.
10853 QualType T = resultType->getAs<ExtVectorType>()->getElementType();
10854 if (!T->isIntegerType())
10855 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
10856 << resultType << Input.get()->getSourceRange());
10857 }
10858 break;
10859 } else {
10860 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
10861 << resultType << Input.get()->getSourceRange());
10862 }
10863 break;
10864
10865 case UO_LNot: // logical negation
10866 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5).
10867 Input = DefaultFunctionArrayLvalueConversion(Input.get());
10868 if (Input.isInvalid()) return ExprError();
10869 resultType = Input.get()->getType();
10870
10871 // Though we still have to promote half FP to float...
10872 if (resultType->isHalfType() && !Context.getLangOpts().NativeHalfType) {
10873 Input = ImpCastExprToType(Input.get(), Context.FloatTy, CK_FloatingCast).get();
10874 resultType = Context.FloatTy;
10875 }
10876
10877 if (resultType->isDependentType())
10878 break;
10879 if (resultType->isScalarType() && !isScopedEnumerationType(resultType)) {
10880 // C99 6.5.3.3p1: ok, fallthrough;
10881 if (Context.getLangOpts().CPlusPlus) {
10882 // C++03 [expr.unary.op]p8, C++0x [expr.unary.op]p9:
10883 // operand contextually converted to bool.
10884 Input = ImpCastExprToType(Input.get(), Context.BoolTy,
10885 ScalarTypeToBooleanCastKind(resultType));
10886 } else if (Context.getLangOpts().OpenCL &&
10887 Context.getLangOpts().OpenCLVersion < 120) {
10888 // OpenCL v1.1 6.3.h: The logical operator not (!) does not
10889 // operate on scalar float types.
10890 if (!resultType->isIntegerType())
10891 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
10892 << resultType << Input.get()->getSourceRange());
10893 }
10894 } else if (resultType->isExtVectorType()) {
10895 if (Context.getLangOpts().OpenCL &&
10896 Context.getLangOpts().OpenCLVersion < 120) {
10897 // OpenCL v1.1 6.3.h: The logical operator not (!) does not
10898 // operate on vector float types.
10899 QualType T = resultType->getAs<ExtVectorType>()->getElementType();
10900 if (!T->isIntegerType())
10901 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
10902 << resultType << Input.get()->getSourceRange());
10903 }
10904 // Vector logical not returns the signed variant of the operand type.
10905 resultType = GetSignedVectorType(resultType);
10906 break;
10907 } else {
10908 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
10909 << resultType << Input.get()->getSourceRange());
10910 }
10911
10912 // LNot always has type int. C99 6.5.3.3p5.
10913 // In C++, it's bool. C++ 5.3.1p8
10914 resultType = Context.getLogicalOperationType();
10915 break;
10916 case UO_Real:
10917 case UO_Imag:
10918 resultType = CheckRealImagOperand(*this, Input, OpLoc, Opc == UO_Real);
10919 // _Real maps ordinary l-values into ordinary l-values. _Imag maps ordinary
10920 // complex l-values to ordinary l-values and all other values to r-values.
10921 if (Input.isInvalid()) return ExprError();
10922 if (Opc == UO_Real || Input.get()->getType()->isAnyComplexType()) {
10923 if (Input.get()->getValueKind() != VK_RValue &&
10924 Input.get()->getObjectKind() == OK_Ordinary)
10925 VK = Input.get()->getValueKind();
10926 } else if (!getLangOpts().CPlusPlus) {
10927 // In C, a volatile scalar is read by __imag. In C++, it is not.
10928 Input = DefaultLvalueConversion(Input.get());
10929 }
10930 break;
10931 case UO_Extension:
10932 case UO_Coawait:
10933 resultType = Input.get()->getType();
10934 VK = Input.get()->getValueKind();
10935 OK = Input.get()->getObjectKind();
10936 break;
10937 }
10938 if (resultType.isNull() || Input.isInvalid())
10939 return ExprError();
10940
10941 // Check for array bounds violations in the operand of the UnaryOperator,
10942 // except for the '*' and '&' operators that have to be handled specially
10943 // by CheckArrayAccess (as there are special cases like &array[arraysize]
10944 // that are explicitly defined as valid by the standard).
10945 if (Opc != UO_AddrOf && Opc != UO_Deref)
10946 CheckArrayAccess(Input.get());
10947
10948 return new (Context)
10949 UnaryOperator(Input.get(), Opc, resultType, VK, OK, OpLoc);
10950 }
10951
10952 /// \brief Determine whether the given expression is a qualified member
10953 /// access expression, of a form that could be turned into a pointer to member
10954 /// with the address-of operator.
isQualifiedMemberAccess(Expr * E)10955 static bool isQualifiedMemberAccess(Expr *E) {
10956 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
10957 if (!DRE->getQualifier())
10958 return false;
10959
10960 ValueDecl *VD = DRE->getDecl();
10961 if (!VD->isCXXClassMember())
10962 return false;
10963
10964 if (isa<FieldDecl>(VD) || isa<IndirectFieldDecl>(VD))
10965 return true;
10966 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(VD))
10967 return Method->isInstance();
10968
10969 return false;
10970 }
10971
10972 if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) {
10973 if (!ULE->getQualifier())
10974 return false;
10975
10976 for (NamedDecl *D : ULE->decls()) {
10977 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
10978 if (Method->isInstance())
10979 return true;
10980 } else {
10981 // Overload set does not contain methods.
10982 break;
10983 }
10984 }
10985
10986 return false;
10987 }
10988
10989 return false;
10990 }
10991
BuildUnaryOp(Scope * S,SourceLocation OpLoc,UnaryOperatorKind Opc,Expr * Input)10992 ExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc,
10993 UnaryOperatorKind Opc, Expr *Input) {
10994 // First things first: handle placeholders so that the
10995 // overloaded-operator check considers the right type.
10996 if (const BuiltinType *pty = Input->getType()->getAsPlaceholderType()) {
10997 // Increment and decrement of pseudo-object references.
10998 if (pty->getKind() == BuiltinType::PseudoObject &&
10999 UnaryOperator::isIncrementDecrementOp(Opc))
11000 return checkPseudoObjectIncDec(S, OpLoc, Opc, Input);
11001
11002 // extension is always a builtin operator.
11003 if (Opc == UO_Extension)
11004 return CreateBuiltinUnaryOp(OpLoc, Opc, Input);
11005
11006 // & gets special logic for several kinds of placeholder.
11007 // The builtin code knows what to do.
11008 if (Opc == UO_AddrOf &&
11009 (pty->getKind() == BuiltinType::Overload ||
11010 pty->getKind() == BuiltinType::UnknownAny ||
11011 pty->getKind() == BuiltinType::BoundMember))
11012 return CreateBuiltinUnaryOp(OpLoc, Opc, Input);
11013
11014 // Anything else needs to be handled now.
11015 ExprResult Result = CheckPlaceholderExpr(Input);
11016 if (Result.isInvalid()) return ExprError();
11017 Input = Result.get();
11018 }
11019
11020 if (getLangOpts().CPlusPlus && Input->getType()->isOverloadableType() &&
11021 UnaryOperator::getOverloadedOperator(Opc) != OO_None &&
11022 !(Opc == UO_AddrOf && isQualifiedMemberAccess(Input))) {
11023 // Find all of the overloaded operators visible from this
11024 // point. We perform both an operator-name lookup from the local
11025 // scope and an argument-dependent lookup based on the types of
11026 // the arguments.
11027 UnresolvedSet<16> Functions;
11028 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc);
11029 if (S && OverOp != OO_None)
11030 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(),
11031 Functions);
11032
11033 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, Input);
11034 }
11035
11036 return CreateBuiltinUnaryOp(OpLoc, Opc, Input);
11037 }
11038
11039 // Unary Operators. 'Tok' is the token for the operator.
ActOnUnaryOp(Scope * S,SourceLocation OpLoc,tok::TokenKind Op,Expr * Input)11040 ExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc,
11041 tok::TokenKind Op, Expr *Input) {
11042 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), Input);
11043 }
11044
11045 /// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo".
ActOnAddrLabel(SourceLocation OpLoc,SourceLocation LabLoc,LabelDecl * TheDecl)11046 ExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, SourceLocation LabLoc,
11047 LabelDecl *TheDecl) {
11048 TheDecl->markUsed(Context);
11049 // Create the AST node. The address of a label always has type 'void*'.
11050 return new (Context) AddrLabelExpr(OpLoc, LabLoc, TheDecl,
11051 Context.getPointerType(Context.VoidTy));
11052 }
11053
11054 /// Given the last statement in a statement-expression, check whether
11055 /// the result is a producing expression (like a call to an
11056 /// ns_returns_retained function) and, if so, rebuild it to hoist the
11057 /// release out of the full-expression. Otherwise, return null.
11058 /// Cannot fail.
maybeRebuildARCConsumingStmt(Stmt * Statement)11059 static Expr *maybeRebuildARCConsumingStmt(Stmt *Statement) {
11060 // Should always be wrapped with one of these.
11061 ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(Statement);
11062 if (!cleanups) return nullptr;
11063
11064 ImplicitCastExpr *cast = dyn_cast<ImplicitCastExpr>(cleanups->getSubExpr());
11065 if (!cast || cast->getCastKind() != CK_ARCConsumeObject)
11066 return nullptr;
11067
11068 // Splice out the cast. This shouldn't modify any interesting
11069 // features of the statement.
11070 Expr *producer = cast->getSubExpr();
11071 assert(producer->getType() == cast->getType());
11072 assert(producer->getValueKind() == cast->getValueKind());
11073 cleanups->setSubExpr(producer);
11074 return cleanups;
11075 }
11076
ActOnStartStmtExpr()11077 void Sema::ActOnStartStmtExpr() {
11078 PushExpressionEvaluationContext(ExprEvalContexts.back().Context);
11079 }
11080
ActOnStmtExprError()11081 void Sema::ActOnStmtExprError() {
11082 // Note that function is also called by TreeTransform when leaving a
11083 // StmtExpr scope without rebuilding anything.
11084
11085 DiscardCleanupsInEvaluationContext();
11086 PopExpressionEvaluationContext();
11087 }
11088
11089 ExprResult
ActOnStmtExpr(SourceLocation LPLoc,Stmt * SubStmt,SourceLocation RPLoc)11090 Sema::ActOnStmtExpr(SourceLocation LPLoc, Stmt *SubStmt,
11091 SourceLocation RPLoc) { // "({..})"
11092 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!");
11093 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt);
11094
11095 if (hasAnyUnrecoverableErrorsInThisFunction())
11096 DiscardCleanupsInEvaluationContext();
11097 assert(!ExprNeedsCleanups && "cleanups within StmtExpr not correctly bound!");
11098 PopExpressionEvaluationContext();
11099
11100 // FIXME: there are a variety of strange constraints to enforce here, for
11101 // example, it is not possible to goto into a stmt expression apparently.
11102 // More semantic analysis is needed.
11103
11104 // If there are sub-stmts in the compound stmt, take the type of the last one
11105 // as the type of the stmtexpr.
11106 QualType Ty = Context.VoidTy;
11107 bool StmtExprMayBindToTemp = false;
11108 if (!Compound->body_empty()) {
11109 Stmt *LastStmt = Compound->body_back();
11110 LabelStmt *LastLabelStmt = nullptr;
11111 // If LastStmt is a label, skip down through into the body.
11112 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) {
11113 LastLabelStmt = Label;
11114 LastStmt = Label->getSubStmt();
11115 }
11116
11117 if (Expr *LastE = dyn_cast<Expr>(LastStmt)) {
11118 // Do function/array conversion on the last expression, but not
11119 // lvalue-to-rvalue. However, initialize an unqualified type.
11120 ExprResult LastExpr = DefaultFunctionArrayConversion(LastE);
11121 if (LastExpr.isInvalid())
11122 return ExprError();
11123 Ty = LastExpr.get()->getType().getUnqualifiedType();
11124
11125 if (!Ty->isDependentType() && !LastExpr.get()->isTypeDependent()) {
11126 // In ARC, if the final expression ends in a consume, splice
11127 // the consume out and bind it later. In the alternate case
11128 // (when dealing with a retainable type), the result
11129 // initialization will create a produce. In both cases the
11130 // result will be +1, and we'll need to balance that out with
11131 // a bind.
11132 if (Expr *rebuiltLastStmt
11133 = maybeRebuildARCConsumingStmt(LastExpr.get())) {
11134 LastExpr = rebuiltLastStmt;
11135 } else {
11136 LastExpr = PerformCopyInitialization(
11137 InitializedEntity::InitializeResult(LPLoc,
11138 Ty,
11139 false),
11140 SourceLocation(),
11141 LastExpr);
11142 }
11143
11144 if (LastExpr.isInvalid())
11145 return ExprError();
11146 if (LastExpr.get() != nullptr) {
11147 if (!LastLabelStmt)
11148 Compound->setLastStmt(LastExpr.get());
11149 else
11150 LastLabelStmt->setSubStmt(LastExpr.get());
11151 StmtExprMayBindToTemp = true;
11152 }
11153 }
11154 }
11155 }
11156
11157 // FIXME: Check that expression type is complete/non-abstract; statement
11158 // expressions are not lvalues.
11159 Expr *ResStmtExpr = new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc);
11160 if (StmtExprMayBindToTemp)
11161 return MaybeBindToTemporary(ResStmtExpr);
11162 return ResStmtExpr;
11163 }
11164
BuildBuiltinOffsetOf(SourceLocation BuiltinLoc,TypeSourceInfo * TInfo,ArrayRef<OffsetOfComponent> Components,SourceLocation RParenLoc)11165 ExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc,
11166 TypeSourceInfo *TInfo,
11167 ArrayRef<OffsetOfComponent> Components,
11168 SourceLocation RParenLoc) {
11169 QualType ArgTy = TInfo->getType();
11170 bool Dependent = ArgTy->isDependentType();
11171 SourceRange TypeRange = TInfo->getTypeLoc().getLocalSourceRange();
11172
11173 // We must have at least one component that refers to the type, and the first
11174 // one is known to be a field designator. Verify that the ArgTy represents
11175 // a struct/union/class.
11176 if (!Dependent && !ArgTy->isRecordType())
11177 return ExprError(Diag(BuiltinLoc, diag::err_offsetof_record_type)
11178 << ArgTy << TypeRange);
11179
11180 // Type must be complete per C99 7.17p3 because a declaring a variable
11181 // with an incomplete type would be ill-formed.
11182 if (!Dependent
11183 && RequireCompleteType(BuiltinLoc, ArgTy,
11184 diag::err_offsetof_incomplete_type, TypeRange))
11185 return ExprError();
11186
11187 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a
11188 // GCC extension, diagnose them.
11189 // FIXME: This diagnostic isn't actually visible because the location is in
11190 // a system header!
11191 if (Components.size() != 1)
11192 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator)
11193 << SourceRange(Components[1].LocStart, Components.back().LocEnd);
11194
11195 bool DidWarnAboutNonPOD = false;
11196 QualType CurrentType = ArgTy;
11197 typedef OffsetOfExpr::OffsetOfNode OffsetOfNode;
11198 SmallVector<OffsetOfNode, 4> Comps;
11199 SmallVector<Expr*, 4> Exprs;
11200 for (const OffsetOfComponent &OC : Components) {
11201 if (OC.isBrackets) {
11202 // Offset of an array sub-field. TODO: Should we allow vector elements?
11203 if (!CurrentType->isDependentType()) {
11204 const ArrayType *AT = Context.getAsArrayType(CurrentType);
11205 if(!AT)
11206 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type)
11207 << CurrentType);
11208 CurrentType = AT->getElementType();
11209 } else
11210 CurrentType = Context.DependentTy;
11211
11212 ExprResult IdxRval = DefaultLvalueConversion(static_cast<Expr*>(OC.U.E));
11213 if (IdxRval.isInvalid())
11214 return ExprError();
11215 Expr *Idx = IdxRval.get();
11216
11217 // The expression must be an integral expression.
11218 // FIXME: An integral constant expression?
11219 if (!Idx->isTypeDependent() && !Idx->isValueDependent() &&
11220 !Idx->getType()->isIntegerType())
11221 return ExprError(Diag(Idx->getLocStart(),
11222 diag::err_typecheck_subscript_not_integer)
11223 << Idx->getSourceRange());
11224
11225 // Record this array index.
11226 Comps.push_back(OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd));
11227 Exprs.push_back(Idx);
11228 continue;
11229 }
11230
11231 // Offset of a field.
11232 if (CurrentType->isDependentType()) {
11233 // We have the offset of a field, but we can't look into the dependent
11234 // type. Just record the identifier of the field.
11235 Comps.push_back(OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd));
11236 CurrentType = Context.DependentTy;
11237 continue;
11238 }
11239
11240 // We need to have a complete type to look into.
11241 if (RequireCompleteType(OC.LocStart, CurrentType,
11242 diag::err_offsetof_incomplete_type))
11243 return ExprError();
11244
11245 // Look for the designated field.
11246 const RecordType *RC = CurrentType->getAs<RecordType>();
11247 if (!RC)
11248 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type)
11249 << CurrentType);
11250 RecordDecl *RD = RC->getDecl();
11251
11252 // C++ [lib.support.types]p5:
11253 // The macro offsetof accepts a restricted set of type arguments in this
11254 // International Standard. type shall be a POD structure or a POD union
11255 // (clause 9).
11256 // C++11 [support.types]p4:
11257 // If type is not a standard-layout class (Clause 9), the results are
11258 // undefined.
11259 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) {
11260 bool IsSafe = LangOpts.CPlusPlus11? CRD->isStandardLayout() : CRD->isPOD();
11261 unsigned DiagID =
11262 LangOpts.CPlusPlus11? diag::ext_offsetof_non_standardlayout_type
11263 : diag::ext_offsetof_non_pod_type;
11264
11265 if (!IsSafe && !DidWarnAboutNonPOD &&
11266 DiagRuntimeBehavior(BuiltinLoc, nullptr,
11267 PDiag(DiagID)
11268 << SourceRange(Components[0].LocStart, OC.LocEnd)
11269 << CurrentType))
11270 DidWarnAboutNonPOD = true;
11271 }
11272
11273 // Look for the field.
11274 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName);
11275 LookupQualifiedName(R, RD);
11276 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>();
11277 IndirectFieldDecl *IndirectMemberDecl = nullptr;
11278 if (!MemberDecl) {
11279 if ((IndirectMemberDecl = R.getAsSingle<IndirectFieldDecl>()))
11280 MemberDecl = IndirectMemberDecl->getAnonField();
11281 }
11282
11283 if (!MemberDecl)
11284 return ExprError(Diag(BuiltinLoc, diag::err_no_member)
11285 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart,
11286 OC.LocEnd));
11287
11288 // C99 7.17p3:
11289 // (If the specified member is a bit-field, the behavior is undefined.)
11290 //
11291 // We diagnose this as an error.
11292 if (MemberDecl->isBitField()) {
11293 Diag(OC.LocEnd, diag::err_offsetof_bitfield)
11294 << MemberDecl->getDeclName()
11295 << SourceRange(BuiltinLoc, RParenLoc);
11296 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl);
11297 return ExprError();
11298 }
11299
11300 RecordDecl *Parent = MemberDecl->getParent();
11301 if (IndirectMemberDecl)
11302 Parent = cast<RecordDecl>(IndirectMemberDecl->getDeclContext());
11303
11304 // If the member was found in a base class, introduce OffsetOfNodes for
11305 // the base class indirections.
11306 CXXBasePaths Paths;
11307 if (IsDerivedFrom(OC.LocStart, CurrentType, Context.getTypeDeclType(Parent),
11308 Paths)) {
11309 if (Paths.getDetectedVirtual()) {
11310 Diag(OC.LocEnd, diag::err_offsetof_field_of_virtual_base)
11311 << MemberDecl->getDeclName()
11312 << SourceRange(BuiltinLoc, RParenLoc);
11313 return ExprError();
11314 }
11315
11316 CXXBasePath &Path = Paths.front();
11317 for (const CXXBasePathElement &B : Path)
11318 Comps.push_back(OffsetOfNode(B.Base));
11319 }
11320
11321 if (IndirectMemberDecl) {
11322 for (auto *FI : IndirectMemberDecl->chain()) {
11323 assert(isa<FieldDecl>(FI));
11324 Comps.push_back(OffsetOfNode(OC.LocStart,
11325 cast<FieldDecl>(FI), OC.LocEnd));
11326 }
11327 } else
11328 Comps.push_back(OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd));
11329
11330 CurrentType = MemberDecl->getType().getNonReferenceType();
11331 }
11332
11333 return OffsetOfExpr::Create(Context, Context.getSizeType(), BuiltinLoc, TInfo,
11334 Comps, Exprs, RParenLoc);
11335 }
11336
ActOnBuiltinOffsetOf(Scope * S,SourceLocation BuiltinLoc,SourceLocation TypeLoc,ParsedType ParsedArgTy,ArrayRef<OffsetOfComponent> Components,SourceLocation RParenLoc)11337 ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S,
11338 SourceLocation BuiltinLoc,
11339 SourceLocation TypeLoc,
11340 ParsedType ParsedArgTy,
11341 ArrayRef<OffsetOfComponent> Components,
11342 SourceLocation RParenLoc) {
11343
11344 TypeSourceInfo *ArgTInfo;
11345 QualType ArgTy = GetTypeFromParser(ParsedArgTy, &ArgTInfo);
11346 if (ArgTy.isNull())
11347 return ExprError();
11348
11349 if (!ArgTInfo)
11350 ArgTInfo = Context.getTrivialTypeSourceInfo(ArgTy, TypeLoc);
11351
11352 return BuildBuiltinOffsetOf(BuiltinLoc, ArgTInfo, Components, RParenLoc);
11353 }
11354
11355
ActOnChooseExpr(SourceLocation BuiltinLoc,Expr * CondExpr,Expr * LHSExpr,Expr * RHSExpr,SourceLocation RPLoc)11356 ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc,
11357 Expr *CondExpr,
11358 Expr *LHSExpr, Expr *RHSExpr,
11359 SourceLocation RPLoc) {
11360 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)");
11361
11362 ExprValueKind VK = VK_RValue;
11363 ExprObjectKind OK = OK_Ordinary;
11364 QualType resType;
11365 bool ValueDependent = false;
11366 bool CondIsTrue = false;
11367 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) {
11368 resType = Context.DependentTy;
11369 ValueDependent = true;
11370 } else {
11371 // The conditional expression is required to be a constant expression.
11372 llvm::APSInt condEval(32);
11373 ExprResult CondICE
11374 = VerifyIntegerConstantExpression(CondExpr, &condEval,
11375 diag::err_typecheck_choose_expr_requires_constant, false);
11376 if (CondICE.isInvalid())
11377 return ExprError();
11378 CondExpr = CondICE.get();
11379 CondIsTrue = condEval.getZExtValue();
11380
11381 // If the condition is > zero, then the AST type is the same as the LSHExpr.
11382 Expr *ActiveExpr = CondIsTrue ? LHSExpr : RHSExpr;
11383
11384 resType = ActiveExpr->getType();
11385 ValueDependent = ActiveExpr->isValueDependent();
11386 VK = ActiveExpr->getValueKind();
11387 OK = ActiveExpr->getObjectKind();
11388 }
11389
11390 return new (Context)
11391 ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, resType, VK, OK, RPLoc,
11392 CondIsTrue, resType->isDependentType(), ValueDependent);
11393 }
11394
11395 //===----------------------------------------------------------------------===//
11396 // Clang Extensions.
11397 //===----------------------------------------------------------------------===//
11398
11399 /// ActOnBlockStart - This callback is invoked when a block literal is started.
ActOnBlockStart(SourceLocation CaretLoc,Scope * CurScope)11400 void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *CurScope) {
11401 BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc);
11402
11403 if (LangOpts.CPlusPlus) {
11404 Decl *ManglingContextDecl;
11405 if (MangleNumberingContext *MCtx =
11406 getCurrentMangleNumberContext(Block->getDeclContext(),
11407 ManglingContextDecl)) {
11408 unsigned ManglingNumber = MCtx->getManglingNumber(Block);
11409 Block->setBlockMangling(ManglingNumber, ManglingContextDecl);
11410 }
11411 }
11412
11413 PushBlockScope(CurScope, Block);
11414 CurContext->addDecl(Block);
11415 if (CurScope)
11416 PushDeclContext(CurScope, Block);
11417 else
11418 CurContext = Block;
11419
11420 getCurBlock()->HasImplicitReturnType = true;
11421
11422 // Enter a new evaluation context to insulate the block from any
11423 // cleanups from the enclosing full-expression.
11424 PushExpressionEvaluationContext(PotentiallyEvaluated);
11425 }
11426
ActOnBlockArguments(SourceLocation CaretLoc,Declarator & ParamInfo,Scope * CurScope)11427 void Sema::ActOnBlockArguments(SourceLocation CaretLoc, Declarator &ParamInfo,
11428 Scope *CurScope) {
11429 assert(ParamInfo.getIdentifier() == nullptr &&
11430 "block-id should have no identifier!");
11431 assert(ParamInfo.getContext() == Declarator::BlockLiteralContext);
11432 BlockScopeInfo *CurBlock = getCurBlock();
11433
11434 TypeSourceInfo *Sig = GetTypeForDeclarator(ParamInfo, CurScope);
11435 QualType T = Sig->getType();
11436
11437 // FIXME: We should allow unexpanded parameter packs here, but that would,
11438 // in turn, make the block expression contain unexpanded parameter packs.
11439 if (DiagnoseUnexpandedParameterPack(CaretLoc, Sig, UPPC_Block)) {
11440 // Drop the parameters.
11441 FunctionProtoType::ExtProtoInfo EPI;
11442 EPI.HasTrailingReturn = false;
11443 EPI.TypeQuals |= DeclSpec::TQ_const;
11444 T = Context.getFunctionType(Context.DependentTy, None, EPI);
11445 Sig = Context.getTrivialTypeSourceInfo(T);
11446 }
11447
11448 // GetTypeForDeclarator always produces a function type for a block
11449 // literal signature. Furthermore, it is always a FunctionProtoType
11450 // unless the function was written with a typedef.
11451 assert(T->isFunctionType() &&
11452 "GetTypeForDeclarator made a non-function block signature");
11453
11454 // Look for an explicit signature in that function type.
11455 FunctionProtoTypeLoc ExplicitSignature;
11456
11457 TypeLoc tmp = Sig->getTypeLoc().IgnoreParens();
11458 if ((ExplicitSignature = tmp.getAs<FunctionProtoTypeLoc>())) {
11459
11460 // Check whether that explicit signature was synthesized by
11461 // GetTypeForDeclarator. If so, don't save that as part of the
11462 // written signature.
11463 if (ExplicitSignature.getLocalRangeBegin() ==
11464 ExplicitSignature.getLocalRangeEnd()) {
11465 // This would be much cheaper if we stored TypeLocs instead of
11466 // TypeSourceInfos.
11467 TypeLoc Result = ExplicitSignature.getReturnLoc();
11468 unsigned Size = Result.getFullDataSize();
11469 Sig = Context.CreateTypeSourceInfo(Result.getType(), Size);
11470 Sig->getTypeLoc().initializeFullCopy(Result, Size);
11471
11472 ExplicitSignature = FunctionProtoTypeLoc();
11473 }
11474 }
11475
11476 CurBlock->TheDecl->setSignatureAsWritten(Sig);
11477 CurBlock->FunctionType = T;
11478
11479 const FunctionType *Fn = T->getAs<FunctionType>();
11480 QualType RetTy = Fn->getReturnType();
11481 bool isVariadic =
11482 (isa<FunctionProtoType>(Fn) && cast<FunctionProtoType>(Fn)->isVariadic());
11483
11484 CurBlock->TheDecl->setIsVariadic(isVariadic);
11485
11486 // Context.DependentTy is used as a placeholder for a missing block
11487 // return type. TODO: what should we do with declarators like:
11488 // ^ * { ... }
11489 // If the answer is "apply template argument deduction"....
11490 if (RetTy != Context.DependentTy) {
11491 CurBlock->ReturnType = RetTy;
11492 CurBlock->TheDecl->setBlockMissingReturnType(false);
11493 CurBlock->HasImplicitReturnType = false;
11494 }
11495
11496 // Push block parameters from the declarator if we had them.
11497 SmallVector<ParmVarDecl*, 8> Params;
11498 if (ExplicitSignature) {
11499 for (unsigned I = 0, E = ExplicitSignature.getNumParams(); I != E; ++I) {
11500 ParmVarDecl *Param = ExplicitSignature.getParam(I);
11501 if (Param->getIdentifier() == nullptr &&
11502 !Param->isImplicit() &&
11503 !Param->isInvalidDecl() &&
11504 !getLangOpts().CPlusPlus)
11505 Diag(Param->getLocation(), diag::err_parameter_name_omitted);
11506 Params.push_back(Param);
11507 }
11508
11509 // Fake up parameter variables if we have a typedef, like
11510 // ^ fntype { ... }
11511 } else if (const FunctionProtoType *Fn = T->getAs<FunctionProtoType>()) {
11512 for (const auto &I : Fn->param_types()) {
11513 ParmVarDecl *Param = BuildParmVarDeclForTypedef(
11514 CurBlock->TheDecl, ParamInfo.getLocStart(), I);
11515 Params.push_back(Param);
11516 }
11517 }
11518
11519 // Set the parameters on the block decl.
11520 if (!Params.empty()) {
11521 CurBlock->TheDecl->setParams(Params);
11522 CheckParmsForFunctionDef(CurBlock->TheDecl->param_begin(),
11523 CurBlock->TheDecl->param_end(),
11524 /*CheckParameterNames=*/false);
11525 }
11526
11527 // Finally we can process decl attributes.
11528 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo);
11529
11530 // Put the parameter variables in scope.
11531 for (auto AI : CurBlock->TheDecl->params()) {
11532 AI->setOwningFunction(CurBlock->TheDecl);
11533
11534 // If this has an identifier, add it to the scope stack.
11535 if (AI->getIdentifier()) {
11536 CheckShadow(CurBlock->TheScope, AI);
11537
11538 PushOnScopeChains(AI, CurBlock->TheScope);
11539 }
11540 }
11541 }
11542
11543 /// ActOnBlockError - If there is an error parsing a block, this callback
11544 /// is invoked to pop the information about the block from the action impl.
ActOnBlockError(SourceLocation CaretLoc,Scope * CurScope)11545 void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) {
11546 // Leave the expression-evaluation context.
11547 DiscardCleanupsInEvaluationContext();
11548 PopExpressionEvaluationContext();
11549
11550 // Pop off CurBlock, handle nested blocks.
11551 PopDeclContext();
11552 PopFunctionScopeInfo();
11553 }
11554
11555 /// ActOnBlockStmtExpr - This is called when the body of a block statement
11556 /// literal was successfully completed. ^(int x){...}
ActOnBlockStmtExpr(SourceLocation CaretLoc,Stmt * Body,Scope * CurScope)11557 ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc,
11558 Stmt *Body, Scope *CurScope) {
11559 // If blocks are disabled, emit an error.
11560 if (!LangOpts.Blocks)
11561 Diag(CaretLoc, diag::err_blocks_disable);
11562
11563 // Leave the expression-evaluation context.
11564 if (hasAnyUnrecoverableErrorsInThisFunction())
11565 DiscardCleanupsInEvaluationContext();
11566 assert(!ExprNeedsCleanups && "cleanups within block not correctly bound!");
11567 PopExpressionEvaluationContext();
11568
11569 BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back());
11570
11571 if (BSI->HasImplicitReturnType)
11572 deduceClosureReturnType(*BSI);
11573
11574 PopDeclContext();
11575
11576 QualType RetTy = Context.VoidTy;
11577 if (!BSI->ReturnType.isNull())
11578 RetTy = BSI->ReturnType;
11579
11580 bool NoReturn = BSI->TheDecl->hasAttr<NoReturnAttr>();
11581 QualType BlockTy;
11582
11583 // Set the captured variables on the block.
11584 // FIXME: Share capture structure between BlockDecl and CapturingScopeInfo!
11585 SmallVector<BlockDecl::Capture, 4> Captures;
11586 for (CapturingScopeInfo::Capture &Cap : BSI->Captures) {
11587 if (Cap.isThisCapture())
11588 continue;
11589 BlockDecl::Capture NewCap(Cap.getVariable(), Cap.isBlockCapture(),
11590 Cap.isNested(), Cap.getInitExpr());
11591 Captures.push_back(NewCap);
11592 }
11593 BSI->TheDecl->setCaptures(Context, Captures, BSI->CXXThisCaptureIndex != 0);
11594
11595 // If the user wrote a function type in some form, try to use that.
11596 if (!BSI->FunctionType.isNull()) {
11597 const FunctionType *FTy = BSI->FunctionType->getAs<FunctionType>();
11598
11599 FunctionType::ExtInfo Ext = FTy->getExtInfo();
11600 if (NoReturn && !Ext.getNoReturn()) Ext = Ext.withNoReturn(true);
11601
11602 // Turn protoless block types into nullary block types.
11603 if (isa<FunctionNoProtoType>(FTy)) {
11604 FunctionProtoType::ExtProtoInfo EPI;
11605 EPI.ExtInfo = Ext;
11606 BlockTy = Context.getFunctionType(RetTy, None, EPI);
11607
11608 // Otherwise, if we don't need to change anything about the function type,
11609 // preserve its sugar structure.
11610 } else if (FTy->getReturnType() == RetTy &&
11611 (!NoReturn || FTy->getNoReturnAttr())) {
11612 BlockTy = BSI->FunctionType;
11613
11614 // Otherwise, make the minimal modifications to the function type.
11615 } else {
11616 const FunctionProtoType *FPT = cast<FunctionProtoType>(FTy);
11617 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
11618 EPI.TypeQuals = 0; // FIXME: silently?
11619 EPI.ExtInfo = Ext;
11620 BlockTy = Context.getFunctionType(RetTy, FPT->getParamTypes(), EPI);
11621 }
11622
11623 // If we don't have a function type, just build one from nothing.
11624 } else {
11625 FunctionProtoType::ExtProtoInfo EPI;
11626 EPI.ExtInfo = FunctionType::ExtInfo().withNoReturn(NoReturn);
11627 BlockTy = Context.getFunctionType(RetTy, None, EPI);
11628 }
11629
11630 DiagnoseUnusedParameters(BSI->TheDecl->param_begin(),
11631 BSI->TheDecl->param_end());
11632 BlockTy = Context.getBlockPointerType(BlockTy);
11633
11634 // If needed, diagnose invalid gotos and switches in the block.
11635 if (getCurFunction()->NeedsScopeChecking() &&
11636 !PP.isCodeCompletionEnabled())
11637 DiagnoseInvalidJumps(cast<CompoundStmt>(Body));
11638
11639 BSI->TheDecl->setBody(cast<CompoundStmt>(Body));
11640
11641 // Try to apply the named return value optimization. We have to check again
11642 // if we can do this, though, because blocks keep return statements around
11643 // to deduce an implicit return type.
11644 if (getLangOpts().CPlusPlus && RetTy->isRecordType() &&
11645 !BSI->TheDecl->isDependentContext())
11646 computeNRVO(Body, BSI);
11647
11648 BlockExpr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy);
11649 AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy();
11650 PopFunctionScopeInfo(&WP, Result->getBlockDecl(), Result);
11651
11652 // If the block isn't obviously global, i.e. it captures anything at
11653 // all, then we need to do a few things in the surrounding context:
11654 if (Result->getBlockDecl()->hasCaptures()) {
11655 // First, this expression has a new cleanup object.
11656 ExprCleanupObjects.push_back(Result->getBlockDecl());
11657 ExprNeedsCleanups = true;
11658
11659 // It also gets a branch-protected scope if any of the captured
11660 // variables needs destruction.
11661 for (const auto &CI : Result->getBlockDecl()->captures()) {
11662 const VarDecl *var = CI.getVariable();
11663 if (var->getType().isDestructedType() != QualType::DK_none) {
11664 getCurFunction()->setHasBranchProtectedScope();
11665 break;
11666 }
11667 }
11668 }
11669
11670 return Result;
11671 }
11672
ActOnVAArg(SourceLocation BuiltinLoc,Expr * E,ParsedType Ty,SourceLocation RPLoc)11673 ExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc,
11674 Expr *E, ParsedType Ty,
11675 SourceLocation RPLoc) {
11676 TypeSourceInfo *TInfo;
11677 GetTypeFromParser(Ty, &TInfo);
11678 return BuildVAArgExpr(BuiltinLoc, E, TInfo, RPLoc);
11679 }
11680
BuildVAArgExpr(SourceLocation BuiltinLoc,Expr * E,TypeSourceInfo * TInfo,SourceLocation RPLoc)11681 ExprResult Sema::BuildVAArgExpr(SourceLocation BuiltinLoc,
11682 Expr *E, TypeSourceInfo *TInfo,
11683 SourceLocation RPLoc) {
11684 Expr *OrigExpr = E;
11685 bool IsMS = false;
11686
11687 // It might be a __builtin_ms_va_list. (But don't ever mark a va_arg()
11688 // as Microsoft ABI on an actual Microsoft platform, where
11689 // __builtin_ms_va_list and __builtin_va_list are the same.)
11690 if (!E->isTypeDependent() && Context.getTargetInfo().hasBuiltinMSVaList() &&
11691 Context.getTargetInfo().getBuiltinVaListKind() != TargetInfo::CharPtrBuiltinVaList) {
11692 QualType MSVaListType = Context.getBuiltinMSVaListType();
11693 if (Context.hasSameType(MSVaListType, E->getType())) {
11694 if (CheckForModifiableLvalue(E, BuiltinLoc, *this))
11695 return ExprError();
11696 IsMS = true;
11697 }
11698 }
11699
11700 // Get the va_list type
11701 QualType VaListType = Context.getBuiltinVaListType();
11702 if (!IsMS) {
11703 if (VaListType->isArrayType()) {
11704 // Deal with implicit array decay; for example, on x86-64,
11705 // va_list is an array, but it's supposed to decay to
11706 // a pointer for va_arg.
11707 VaListType = Context.getArrayDecayedType(VaListType);
11708 // Make sure the input expression also decays appropriately.
11709 ExprResult Result = UsualUnaryConversions(E);
11710 if (Result.isInvalid())
11711 return ExprError();
11712 E = Result.get();
11713 } else if (VaListType->isRecordType() && getLangOpts().CPlusPlus) {
11714 // If va_list is a record type and we are compiling in C++ mode,
11715 // check the argument using reference binding.
11716 InitializedEntity Entity = InitializedEntity::InitializeParameter(
11717 Context, Context.getLValueReferenceType(VaListType), false);
11718 ExprResult Init = PerformCopyInitialization(Entity, SourceLocation(), E);
11719 if (Init.isInvalid())
11720 return ExprError();
11721 E = Init.getAs<Expr>();
11722 } else {
11723 // Otherwise, the va_list argument must be an l-value because
11724 // it is modified by va_arg.
11725 if (!E->isTypeDependent() &&
11726 CheckForModifiableLvalue(E, BuiltinLoc, *this))
11727 return ExprError();
11728 }
11729 }
11730
11731 if (!IsMS && !E->isTypeDependent() &&
11732 !Context.hasSameType(VaListType, E->getType()))
11733 return ExprError(Diag(E->getLocStart(),
11734 diag::err_first_argument_to_va_arg_not_of_type_va_list)
11735 << OrigExpr->getType() << E->getSourceRange());
11736
11737 if (!TInfo->getType()->isDependentType()) {
11738 if (RequireCompleteType(TInfo->getTypeLoc().getBeginLoc(), TInfo->getType(),
11739 diag::err_second_parameter_to_va_arg_incomplete,
11740 TInfo->getTypeLoc()))
11741 return ExprError();
11742
11743 if (RequireNonAbstractType(TInfo->getTypeLoc().getBeginLoc(),
11744 TInfo->getType(),
11745 diag::err_second_parameter_to_va_arg_abstract,
11746 TInfo->getTypeLoc()))
11747 return ExprError();
11748
11749 if (!TInfo->getType().isPODType(Context)) {
11750 Diag(TInfo->getTypeLoc().getBeginLoc(),
11751 TInfo->getType()->isObjCLifetimeType()
11752 ? diag::warn_second_parameter_to_va_arg_ownership_qualified
11753 : diag::warn_second_parameter_to_va_arg_not_pod)
11754 << TInfo->getType()
11755 << TInfo->getTypeLoc().getSourceRange();
11756 }
11757
11758 // Check for va_arg where arguments of the given type will be promoted
11759 // (i.e. this va_arg is guaranteed to have undefined behavior).
11760 QualType PromoteType;
11761 if (TInfo->getType()->isPromotableIntegerType()) {
11762 PromoteType = Context.getPromotedIntegerType(TInfo->getType());
11763 if (Context.typesAreCompatible(PromoteType, TInfo->getType()))
11764 PromoteType = QualType();
11765 }
11766 if (TInfo->getType()->isSpecificBuiltinType(BuiltinType::Float))
11767 PromoteType = Context.DoubleTy;
11768 if (!PromoteType.isNull())
11769 DiagRuntimeBehavior(TInfo->getTypeLoc().getBeginLoc(), E,
11770 PDiag(diag::warn_second_parameter_to_va_arg_never_compatible)
11771 << TInfo->getType()
11772 << PromoteType
11773 << TInfo->getTypeLoc().getSourceRange());
11774 }
11775
11776 QualType T = TInfo->getType().getNonLValueExprType(Context);
11777 return new (Context) VAArgExpr(BuiltinLoc, E, TInfo, RPLoc, T, IsMS);
11778 }
11779
ActOnGNUNullExpr(SourceLocation TokenLoc)11780 ExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) {
11781 // The type of __null will be int or long, depending on the size of
11782 // pointers on the target.
11783 QualType Ty;
11784 unsigned pw = Context.getTargetInfo().getPointerWidth(0);
11785 if (pw == Context.getTargetInfo().getIntWidth())
11786 Ty = Context.IntTy;
11787 else if (pw == Context.getTargetInfo().getLongWidth())
11788 Ty = Context.LongTy;
11789 else if (pw == Context.getTargetInfo().getLongLongWidth())
11790 Ty = Context.LongLongTy;
11791 else {
11792 llvm_unreachable("I don't know size of pointer!");
11793 }
11794
11795 return new (Context) GNUNullExpr(Ty, TokenLoc);
11796 }
11797
11798 bool
ConversionToObjCStringLiteralCheck(QualType DstType,Expr * & Exp)11799 Sema::ConversionToObjCStringLiteralCheck(QualType DstType, Expr *&Exp) {
11800 if (!getLangOpts().ObjC1)
11801 return false;
11802
11803 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>();
11804 if (!PT)
11805 return false;
11806
11807 if (!PT->isObjCIdType()) {
11808 // Check if the destination is the 'NSString' interface.
11809 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl();
11810 if (!ID || !ID->getIdentifier()->isStr("NSString"))
11811 return false;
11812 }
11813
11814 // Ignore any parens, implicit casts (should only be
11815 // array-to-pointer decays), and not-so-opaque values. The last is
11816 // important for making this trigger for property assignments.
11817 Expr *SrcExpr = Exp->IgnoreParenImpCasts();
11818 if (OpaqueValueExpr *OV = dyn_cast<OpaqueValueExpr>(SrcExpr))
11819 if (OV->getSourceExpr())
11820 SrcExpr = OV->getSourceExpr()->IgnoreParenImpCasts();
11821
11822 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr);
11823 if (!SL || !SL->isAscii())
11824 return false;
11825 Diag(SL->getLocStart(), diag::err_missing_atsign_prefix)
11826 << FixItHint::CreateInsertion(SL->getLocStart(), "@");
11827 Exp = BuildObjCStringLiteral(SL->getLocStart(), SL).get();
11828 return true;
11829 }
11830
maybeDiagnoseAssignmentToFunction(Sema & S,QualType DstType,const Expr * SrcExpr)11831 static bool maybeDiagnoseAssignmentToFunction(Sema &S, QualType DstType,
11832 const Expr *SrcExpr) {
11833 if (!DstType->isFunctionPointerType() ||
11834 !SrcExpr->getType()->isFunctionType())
11835 return false;
11836
11837 auto *DRE = dyn_cast<DeclRefExpr>(SrcExpr->IgnoreParenImpCasts());
11838 if (!DRE)
11839 return false;
11840
11841 auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl());
11842 if (!FD)
11843 return false;
11844
11845 return !S.checkAddressOfFunctionIsAvailable(FD,
11846 /*Complain=*/true,
11847 SrcExpr->getLocStart());
11848 }
11849
DiagnoseAssignmentResult(AssignConvertType ConvTy,SourceLocation Loc,QualType DstType,QualType SrcType,Expr * SrcExpr,AssignmentAction Action,bool * Complained)11850 bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy,
11851 SourceLocation Loc,
11852 QualType DstType, QualType SrcType,
11853 Expr *SrcExpr, AssignmentAction Action,
11854 bool *Complained) {
11855 if (Complained)
11856 *Complained = false;
11857
11858 // Decode the result (notice that AST's are still created for extensions).
11859 bool CheckInferredResultType = false;
11860 bool isInvalid = false;
11861 unsigned DiagKind = 0;
11862 FixItHint Hint;
11863 ConversionFixItGenerator ConvHints;
11864 bool MayHaveConvFixit = false;
11865 bool MayHaveFunctionDiff = false;
11866 const ObjCInterfaceDecl *IFace = nullptr;
11867 const ObjCProtocolDecl *PDecl = nullptr;
11868
11869 switch (ConvTy) {
11870 case Compatible:
11871 DiagnoseAssignmentEnum(DstType, SrcType, SrcExpr);
11872 return false;
11873
11874 case PointerToInt:
11875 DiagKind = diag::ext_typecheck_convert_pointer_int;
11876 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this);
11877 MayHaveConvFixit = true;
11878 break;
11879 case IntToPointer:
11880 DiagKind = diag::ext_typecheck_convert_int_pointer;
11881 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this);
11882 MayHaveConvFixit = true;
11883 break;
11884 case IncompatiblePointer:
11885 DiagKind =
11886 (Action == AA_Passing_CFAudited ?
11887 diag::err_arc_typecheck_convert_incompatible_pointer :
11888 diag::ext_typecheck_convert_incompatible_pointer);
11889 CheckInferredResultType = DstType->isObjCObjectPointerType() &&
11890 SrcType->isObjCObjectPointerType();
11891 if (Hint.isNull() && !CheckInferredResultType) {
11892 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this);
11893 }
11894 else if (CheckInferredResultType) {
11895 SrcType = SrcType.getUnqualifiedType();
11896 DstType = DstType.getUnqualifiedType();
11897 }
11898 MayHaveConvFixit = true;
11899 break;
11900 case IncompatiblePointerSign:
11901 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign;
11902 break;
11903 case FunctionVoidPointer:
11904 DiagKind = diag::ext_typecheck_convert_pointer_void_func;
11905 break;
11906 case IncompatiblePointerDiscardsQualifiers: {
11907 // Perform array-to-pointer decay if necessary.
11908 if (SrcType->isArrayType()) SrcType = Context.getArrayDecayedType(SrcType);
11909
11910 Qualifiers lhq = SrcType->getPointeeType().getQualifiers();
11911 Qualifiers rhq = DstType->getPointeeType().getQualifiers();
11912 if (lhq.getAddressSpace() != rhq.getAddressSpace()) {
11913 DiagKind = diag::err_typecheck_incompatible_address_space;
11914 break;
11915
11916
11917 } else if (lhq.getObjCLifetime() != rhq.getObjCLifetime()) {
11918 DiagKind = diag::err_typecheck_incompatible_ownership;
11919 break;
11920 }
11921
11922 llvm_unreachable("unknown error case for discarding qualifiers!");
11923 // fallthrough
11924 }
11925 case CompatiblePointerDiscardsQualifiers:
11926 // If the qualifiers lost were because we were applying the
11927 // (deprecated) C++ conversion from a string literal to a char*
11928 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME:
11929 // Ideally, this check would be performed in
11930 // checkPointerTypesForAssignment. However, that would require a
11931 // bit of refactoring (so that the second argument is an
11932 // expression, rather than a type), which should be done as part
11933 // of a larger effort to fix checkPointerTypesForAssignment for
11934 // C++ semantics.
11935 if (getLangOpts().CPlusPlus &&
11936 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType))
11937 return false;
11938 DiagKind = diag::ext_typecheck_convert_discards_qualifiers;
11939 break;
11940 case IncompatibleNestedPointerQualifiers:
11941 DiagKind = diag::ext_nested_pointer_qualifier_mismatch;
11942 break;
11943 case IntToBlockPointer:
11944 DiagKind = diag::err_int_to_block_pointer;
11945 break;
11946 case IncompatibleBlockPointer:
11947 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer;
11948 break;
11949 case IncompatibleObjCQualifiedId: {
11950 if (SrcType->isObjCQualifiedIdType()) {
11951 const ObjCObjectPointerType *srcOPT =
11952 SrcType->getAs<ObjCObjectPointerType>();
11953 for (auto *srcProto : srcOPT->quals()) {
11954 PDecl = srcProto;
11955 break;
11956 }
11957 if (const ObjCInterfaceType *IFaceT =
11958 DstType->getAs<ObjCObjectPointerType>()->getInterfaceType())
11959 IFace = IFaceT->getDecl();
11960 }
11961 else if (DstType->isObjCQualifiedIdType()) {
11962 const ObjCObjectPointerType *dstOPT =
11963 DstType->getAs<ObjCObjectPointerType>();
11964 for (auto *dstProto : dstOPT->quals()) {
11965 PDecl = dstProto;
11966 break;
11967 }
11968 if (const ObjCInterfaceType *IFaceT =
11969 SrcType->getAs<ObjCObjectPointerType>()->getInterfaceType())
11970 IFace = IFaceT->getDecl();
11971 }
11972 DiagKind = diag::warn_incompatible_qualified_id;
11973 break;
11974 }
11975 case IncompatibleVectors:
11976 DiagKind = diag::warn_incompatible_vectors;
11977 break;
11978 case IncompatibleObjCWeakRef:
11979 DiagKind = diag::err_arc_weak_unavailable_assign;
11980 break;
11981 case Incompatible:
11982 if (maybeDiagnoseAssignmentToFunction(*this, DstType, SrcExpr)) {
11983 if (Complained)
11984 *Complained = true;
11985 return true;
11986 }
11987
11988 DiagKind = diag::err_typecheck_convert_incompatible;
11989 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this);
11990 MayHaveConvFixit = true;
11991 isInvalid = true;
11992 MayHaveFunctionDiff = true;
11993 break;
11994 }
11995
11996 QualType FirstType, SecondType;
11997 switch (Action) {
11998 case AA_Assigning:
11999 case AA_Initializing:
12000 // The destination type comes first.
12001 FirstType = DstType;
12002 SecondType = SrcType;
12003 break;
12004
12005 case AA_Returning:
12006 case AA_Passing:
12007 case AA_Passing_CFAudited:
12008 case AA_Converting:
12009 case AA_Sending:
12010 case AA_Casting:
12011 // The source type comes first.
12012 FirstType = SrcType;
12013 SecondType = DstType;
12014 break;
12015 }
12016
12017 PartialDiagnostic FDiag = PDiag(DiagKind);
12018 if (Action == AA_Passing_CFAudited)
12019 FDiag << FirstType << SecondType << AA_Passing << SrcExpr->getSourceRange();
12020 else
12021 FDiag << FirstType << SecondType << Action << SrcExpr->getSourceRange();
12022
12023 // If we can fix the conversion, suggest the FixIts.
12024 assert(ConvHints.isNull() || Hint.isNull());
12025 if (!ConvHints.isNull()) {
12026 for (FixItHint &H : ConvHints.Hints)
12027 FDiag << H;
12028 } else {
12029 FDiag << Hint;
12030 }
12031 if (MayHaveConvFixit) { FDiag << (unsigned) (ConvHints.Kind); }
12032
12033 if (MayHaveFunctionDiff)
12034 HandleFunctionTypeMismatch(FDiag, SecondType, FirstType);
12035
12036 Diag(Loc, FDiag);
12037 if (DiagKind == diag::warn_incompatible_qualified_id &&
12038 PDecl && IFace && !IFace->hasDefinition())
12039 Diag(IFace->getLocation(), diag::not_incomplete_class_and_qualified_id)
12040 << IFace->getName() << PDecl->getName();
12041
12042 if (SecondType == Context.OverloadTy)
12043 NoteAllOverloadCandidates(OverloadExpr::find(SrcExpr).Expression,
12044 FirstType, /*TakingAddress=*/true);
12045
12046 if (CheckInferredResultType)
12047 EmitRelatedResultTypeNote(SrcExpr);
12048
12049 if (Action == AA_Returning && ConvTy == IncompatiblePointer)
12050 EmitRelatedResultTypeNoteForReturn(DstType);
12051
12052 if (Complained)
12053 *Complained = true;
12054 return isInvalid;
12055 }
12056
VerifyIntegerConstantExpression(Expr * E,llvm::APSInt * Result)12057 ExprResult Sema::VerifyIntegerConstantExpression(Expr *E,
12058 llvm::APSInt *Result) {
12059 class SimpleICEDiagnoser : public VerifyICEDiagnoser {
12060 public:
12061 void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) override {
12062 S.Diag(Loc, diag::err_expr_not_ice) << S.LangOpts.CPlusPlus << SR;
12063 }
12064 } Diagnoser;
12065
12066 return VerifyIntegerConstantExpression(E, Result, Diagnoser);
12067 }
12068
VerifyIntegerConstantExpression(Expr * E,llvm::APSInt * Result,unsigned DiagID,bool AllowFold)12069 ExprResult Sema::VerifyIntegerConstantExpression(Expr *E,
12070 llvm::APSInt *Result,
12071 unsigned DiagID,
12072 bool AllowFold) {
12073 class IDDiagnoser : public VerifyICEDiagnoser {
12074 unsigned DiagID;
12075
12076 public:
12077 IDDiagnoser(unsigned DiagID)
12078 : VerifyICEDiagnoser(DiagID == 0), DiagID(DiagID) { }
12079
12080 void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) override {
12081 S.Diag(Loc, DiagID) << SR;
12082 }
12083 } Diagnoser(DiagID);
12084
12085 return VerifyIntegerConstantExpression(E, Result, Diagnoser, AllowFold);
12086 }
12087
diagnoseFold(Sema & S,SourceLocation Loc,SourceRange SR)12088 void Sema::VerifyICEDiagnoser::diagnoseFold(Sema &S, SourceLocation Loc,
12089 SourceRange SR) {
12090 S.Diag(Loc, diag::ext_expr_not_ice) << SR << S.LangOpts.CPlusPlus;
12091 }
12092
12093 ExprResult
VerifyIntegerConstantExpression(Expr * E,llvm::APSInt * Result,VerifyICEDiagnoser & Diagnoser,bool AllowFold)12094 Sema::VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
12095 VerifyICEDiagnoser &Diagnoser,
12096 bool AllowFold) {
12097 SourceLocation DiagLoc = E->getLocStart();
12098
12099 if (getLangOpts().CPlusPlus11) {
12100 // C++11 [expr.const]p5:
12101 // If an expression of literal class type is used in a context where an
12102 // integral constant expression is required, then that class type shall
12103 // have a single non-explicit conversion function to an integral or
12104 // unscoped enumeration type
12105 ExprResult Converted;
12106 class CXX11ConvertDiagnoser : public ICEConvertDiagnoser {
12107 public:
12108 CXX11ConvertDiagnoser(bool Silent)
12109 : ICEConvertDiagnoser(/*AllowScopedEnumerations*/false,
12110 Silent, true) {}
12111
12112 SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
12113 QualType T) override {
12114 return S.Diag(Loc, diag::err_ice_not_integral) << T;
12115 }
12116
12117 SemaDiagnosticBuilder diagnoseIncomplete(
12118 Sema &S, SourceLocation Loc, QualType T) override {
12119 return S.Diag(Loc, diag::err_ice_incomplete_type) << T;
12120 }
12121
12122 SemaDiagnosticBuilder diagnoseExplicitConv(
12123 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
12124 return S.Diag(Loc, diag::err_ice_explicit_conversion) << T << ConvTy;
12125 }
12126
12127 SemaDiagnosticBuilder noteExplicitConv(
12128 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
12129 return S.Diag(Conv->getLocation(), diag::note_ice_conversion_here)
12130 << ConvTy->isEnumeralType() << ConvTy;
12131 }
12132
12133 SemaDiagnosticBuilder diagnoseAmbiguous(
12134 Sema &S, SourceLocation Loc, QualType T) override {
12135 return S.Diag(Loc, diag::err_ice_ambiguous_conversion) << T;
12136 }
12137
12138 SemaDiagnosticBuilder noteAmbiguous(
12139 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
12140 return S.Diag(Conv->getLocation(), diag::note_ice_conversion_here)
12141 << ConvTy->isEnumeralType() << ConvTy;
12142 }
12143
12144 SemaDiagnosticBuilder diagnoseConversion(
12145 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
12146 llvm_unreachable("conversion functions are permitted");
12147 }
12148 } ConvertDiagnoser(Diagnoser.Suppress);
12149
12150 Converted = PerformContextualImplicitConversion(DiagLoc, E,
12151 ConvertDiagnoser);
12152 if (Converted.isInvalid())
12153 return Converted;
12154 E = Converted.get();
12155 if (!E->getType()->isIntegralOrUnscopedEnumerationType())
12156 return ExprError();
12157 } else if (!E->getType()->isIntegralOrUnscopedEnumerationType()) {
12158 // An ICE must be of integral or unscoped enumeration type.
12159 if (!Diagnoser.Suppress)
12160 Diagnoser.diagnoseNotICE(*this, DiagLoc, E->getSourceRange());
12161 return ExprError();
12162 }
12163
12164 // Circumvent ICE checking in C++11 to avoid evaluating the expression twice
12165 // in the non-ICE case.
12166 if (!getLangOpts().CPlusPlus11 && E->isIntegerConstantExpr(Context)) {
12167 if (Result)
12168 *Result = E->EvaluateKnownConstInt(Context);
12169 return E;
12170 }
12171
12172 Expr::EvalResult EvalResult;
12173 SmallVector<PartialDiagnosticAt, 8> Notes;
12174 EvalResult.Diag = &Notes;
12175
12176 // Try to evaluate the expression, and produce diagnostics explaining why it's
12177 // not a constant expression as a side-effect.
12178 bool Folded = E->EvaluateAsRValue(EvalResult, Context) &&
12179 EvalResult.Val.isInt() && !EvalResult.HasSideEffects;
12180
12181 // In C++11, we can rely on diagnostics being produced for any expression
12182 // which is not a constant expression. If no diagnostics were produced, then
12183 // this is a constant expression.
12184 if (Folded && getLangOpts().CPlusPlus11 && Notes.empty()) {
12185 if (Result)
12186 *Result = EvalResult.Val.getInt();
12187 return E;
12188 }
12189
12190 // If our only note is the usual "invalid subexpression" note, just point
12191 // the caret at its location rather than producing an essentially
12192 // redundant note.
12193 if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
12194 diag::note_invalid_subexpr_in_const_expr) {
12195 DiagLoc = Notes[0].first;
12196 Notes.clear();
12197 }
12198
12199 if (!Folded || !AllowFold) {
12200 if (!Diagnoser.Suppress) {
12201 Diagnoser.diagnoseNotICE(*this, DiagLoc, E->getSourceRange());
12202 for (const PartialDiagnosticAt &Note : Notes)
12203 Diag(Note.first, Note.second);
12204 }
12205
12206 return ExprError();
12207 }
12208
12209 Diagnoser.diagnoseFold(*this, DiagLoc, E->getSourceRange());
12210 for (const PartialDiagnosticAt &Note : Notes)
12211 Diag(Note.first, Note.second);
12212
12213 if (Result)
12214 *Result = EvalResult.Val.getInt();
12215 return E;
12216 }
12217
12218 namespace {
12219 // Handle the case where we conclude a expression which we speculatively
12220 // considered to be unevaluated is actually evaluated.
12221 class TransformToPE : public TreeTransform<TransformToPE> {
12222 typedef TreeTransform<TransformToPE> BaseTransform;
12223
12224 public:
TransformToPE(Sema & SemaRef)12225 TransformToPE(Sema &SemaRef) : BaseTransform(SemaRef) { }
12226
12227 // Make sure we redo semantic analysis
AlwaysRebuild()12228 bool AlwaysRebuild() { return true; }
12229
12230 // Make sure we handle LabelStmts correctly.
12231 // FIXME: This does the right thing, but maybe we need a more general
12232 // fix to TreeTransform?
TransformLabelStmt(LabelStmt * S)12233 StmtResult TransformLabelStmt(LabelStmt *S) {
12234 S->getDecl()->setStmt(nullptr);
12235 return BaseTransform::TransformLabelStmt(S);
12236 }
12237
12238 // We need to special-case DeclRefExprs referring to FieldDecls which
12239 // are not part of a member pointer formation; normal TreeTransforming
12240 // doesn't catch this case because of the way we represent them in the AST.
12241 // FIXME: This is a bit ugly; is it really the best way to handle this
12242 // case?
12243 //
12244 // Error on DeclRefExprs referring to FieldDecls.
TransformDeclRefExpr(DeclRefExpr * E)12245 ExprResult TransformDeclRefExpr(DeclRefExpr *E) {
12246 if (isa<FieldDecl>(E->getDecl()) &&
12247 !SemaRef.isUnevaluatedContext())
12248 return SemaRef.Diag(E->getLocation(),
12249 diag::err_invalid_non_static_member_use)
12250 << E->getDecl() << E->getSourceRange();
12251
12252 return BaseTransform::TransformDeclRefExpr(E);
12253 }
12254
12255 // Exception: filter out member pointer formation
TransformUnaryOperator(UnaryOperator * E)12256 ExprResult TransformUnaryOperator(UnaryOperator *E) {
12257 if (E->getOpcode() == UO_AddrOf && E->getType()->isMemberPointerType())
12258 return E;
12259
12260 return BaseTransform::TransformUnaryOperator(E);
12261 }
12262
TransformLambdaExpr(LambdaExpr * E)12263 ExprResult TransformLambdaExpr(LambdaExpr *E) {
12264 // Lambdas never need to be transformed.
12265 return E;
12266 }
12267 };
12268 }
12269
TransformToPotentiallyEvaluated(Expr * E)12270 ExprResult Sema::TransformToPotentiallyEvaluated(Expr *E) {
12271 assert(isUnevaluatedContext() &&
12272 "Should only transform unevaluated expressions");
12273 ExprEvalContexts.back().Context =
12274 ExprEvalContexts[ExprEvalContexts.size()-2].Context;
12275 if (isUnevaluatedContext())
12276 return E;
12277 return TransformToPE(*this).TransformExpr(E);
12278 }
12279
12280 void
PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext,Decl * LambdaContextDecl,bool IsDecltype)12281 Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext,
12282 Decl *LambdaContextDecl,
12283 bool IsDecltype) {
12284 ExprEvalContexts.emplace_back(NewContext, ExprCleanupObjects.size(),
12285 ExprNeedsCleanups, LambdaContextDecl,
12286 IsDecltype);
12287 ExprNeedsCleanups = false;
12288 if (!MaybeODRUseExprs.empty())
12289 std::swap(MaybeODRUseExprs, ExprEvalContexts.back().SavedMaybeODRUseExprs);
12290 }
12291
12292 void
PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext,ReuseLambdaContextDecl_t,bool IsDecltype)12293 Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext,
12294 ReuseLambdaContextDecl_t,
12295 bool IsDecltype) {
12296 Decl *ClosureContextDecl = ExprEvalContexts.back().ManglingContextDecl;
12297 PushExpressionEvaluationContext(NewContext, ClosureContextDecl, IsDecltype);
12298 }
12299
PopExpressionEvaluationContext()12300 void Sema::PopExpressionEvaluationContext() {
12301 ExpressionEvaluationContextRecord& Rec = ExprEvalContexts.back();
12302 unsigned NumTypos = Rec.NumTypos;
12303
12304 if (!Rec.Lambdas.empty()) {
12305 if (Rec.isUnevaluated() || Rec.Context == ConstantEvaluated) {
12306 unsigned D;
12307 if (Rec.isUnevaluated()) {
12308 // C++11 [expr.prim.lambda]p2:
12309 // A lambda-expression shall not appear in an unevaluated operand
12310 // (Clause 5).
12311 D = diag::err_lambda_unevaluated_operand;
12312 } else {
12313 // C++1y [expr.const]p2:
12314 // A conditional-expression e is a core constant expression unless the
12315 // evaluation of e, following the rules of the abstract machine, would
12316 // evaluate [...] a lambda-expression.
12317 D = diag::err_lambda_in_constant_expression;
12318 }
12319 for (const auto *L : Rec.Lambdas)
12320 Diag(L->getLocStart(), D);
12321 } else {
12322 // Mark the capture expressions odr-used. This was deferred
12323 // during lambda expression creation.
12324 for (auto *Lambda : Rec.Lambdas) {
12325 for (auto *C : Lambda->capture_inits())
12326 MarkDeclarationsReferencedInExpr(C);
12327 }
12328 }
12329 }
12330
12331 // When are coming out of an unevaluated context, clear out any
12332 // temporaries that we may have created as part of the evaluation of
12333 // the expression in that context: they aren't relevant because they
12334 // will never be constructed.
12335 if (Rec.isUnevaluated() || Rec.Context == ConstantEvaluated) {
12336 ExprCleanupObjects.erase(ExprCleanupObjects.begin() + Rec.NumCleanupObjects,
12337 ExprCleanupObjects.end());
12338 ExprNeedsCleanups = Rec.ParentNeedsCleanups;
12339 CleanupVarDeclMarking();
12340 std::swap(MaybeODRUseExprs, Rec.SavedMaybeODRUseExprs);
12341 // Otherwise, merge the contexts together.
12342 } else {
12343 ExprNeedsCleanups |= Rec.ParentNeedsCleanups;
12344 MaybeODRUseExprs.insert(Rec.SavedMaybeODRUseExprs.begin(),
12345 Rec.SavedMaybeODRUseExprs.end());
12346 }
12347
12348 // Pop the current expression evaluation context off the stack.
12349 ExprEvalContexts.pop_back();
12350
12351 if (!ExprEvalContexts.empty())
12352 ExprEvalContexts.back().NumTypos += NumTypos;
12353 else
12354 assert(NumTypos == 0 && "There are outstanding typos after popping the "
12355 "last ExpressionEvaluationContextRecord");
12356 }
12357
DiscardCleanupsInEvaluationContext()12358 void Sema::DiscardCleanupsInEvaluationContext() {
12359 ExprCleanupObjects.erase(
12360 ExprCleanupObjects.begin() + ExprEvalContexts.back().NumCleanupObjects,
12361 ExprCleanupObjects.end());
12362 ExprNeedsCleanups = false;
12363 MaybeODRUseExprs.clear();
12364 }
12365
HandleExprEvaluationContextForTypeof(Expr * E)12366 ExprResult Sema::HandleExprEvaluationContextForTypeof(Expr *E) {
12367 if (!E->getType()->isVariablyModifiedType())
12368 return E;
12369 return TransformToPotentiallyEvaluated(E);
12370 }
12371
IsPotentiallyEvaluatedContext(Sema & SemaRef)12372 static bool IsPotentiallyEvaluatedContext(Sema &SemaRef) {
12373 // Do not mark anything as "used" within a dependent context; wait for
12374 // an instantiation.
12375 if (SemaRef.CurContext->isDependentContext())
12376 return false;
12377
12378 switch (SemaRef.ExprEvalContexts.back().Context) {
12379 case Sema::Unevaluated:
12380 case Sema::UnevaluatedAbstract:
12381 // We are in an expression that is not potentially evaluated; do nothing.
12382 // (Depending on how you read the standard, we actually do need to do
12383 // something here for null pointer constants, but the standard's
12384 // definition of a null pointer constant is completely crazy.)
12385 return false;
12386
12387 case Sema::ConstantEvaluated:
12388 case Sema::PotentiallyEvaluated:
12389 // We are in a potentially evaluated expression (or a constant-expression
12390 // in C++03); we need to do implicit template instantiation, implicitly
12391 // define class members, and mark most declarations as used.
12392 return true;
12393
12394 case Sema::PotentiallyEvaluatedIfUsed:
12395 // Referenced declarations will only be used if the construct in the
12396 // containing expression is used.
12397 return false;
12398 }
12399 llvm_unreachable("Invalid context");
12400 }
12401
12402 /// \brief Mark a function referenced, and check whether it is odr-used
12403 /// (C++ [basic.def.odr]p2, C99 6.9p3)
MarkFunctionReferenced(SourceLocation Loc,FunctionDecl * Func,bool OdrUse)12404 void Sema::MarkFunctionReferenced(SourceLocation Loc, FunctionDecl *Func,
12405 bool OdrUse) {
12406 assert(Func && "No function?");
12407
12408 Func->setReferenced();
12409
12410 // C++11 [basic.def.odr]p3:
12411 // A function whose name appears as a potentially-evaluated expression is
12412 // odr-used if it is the unique lookup result or the selected member of a
12413 // set of overloaded functions [...].
12414 //
12415 // We (incorrectly) mark overload resolution as an unevaluated context, so we
12416 // can just check that here. Skip the rest of this function if we've already
12417 // marked the function as used.
12418 if (Func->isUsed(/*CheckUsedAttr=*/false) ||
12419 !IsPotentiallyEvaluatedContext(*this)) {
12420 // C++11 [temp.inst]p3:
12421 // Unless a function template specialization has been explicitly
12422 // instantiated or explicitly specialized, the function template
12423 // specialization is implicitly instantiated when the specialization is
12424 // referenced in a context that requires a function definition to exist.
12425 //
12426 // We consider constexpr function templates to be referenced in a context
12427 // that requires a definition to exist whenever they are referenced.
12428 //
12429 // FIXME: This instantiates constexpr functions too frequently. If this is
12430 // really an unevaluated context (and we're not just in the definition of a
12431 // function template or overload resolution or other cases which we
12432 // incorrectly consider to be unevaluated contexts), and we're not in a
12433 // subexpression which we actually need to evaluate (for instance, a
12434 // template argument, array bound or an expression in a braced-init-list),
12435 // we are not permitted to instantiate this constexpr function definition.
12436 //
12437 // FIXME: This also implicitly defines special members too frequently. They
12438 // are only supposed to be implicitly defined if they are odr-used, but they
12439 // are not odr-used from constant expressions in unevaluated contexts.
12440 // However, they cannot be referenced if they are deleted, and they are
12441 // deleted whenever the implicit definition of the special member would
12442 // fail.
12443 if (!Func->isConstexpr() || Func->getBody())
12444 return;
12445 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Func);
12446 if (!Func->isImplicitlyInstantiable() && (!MD || MD->isUserProvided()))
12447 return;
12448 }
12449
12450 // Note that this declaration has been used.
12451 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Func)) {
12452 Constructor = cast<CXXConstructorDecl>(Constructor->getFirstDecl());
12453 if (Constructor->isDefaulted() && !Constructor->isDeleted()) {
12454 if (Constructor->isDefaultConstructor()) {
12455 if (Constructor->isTrivial() && !Constructor->hasAttr<DLLExportAttr>())
12456 return;
12457 DefineImplicitDefaultConstructor(Loc, Constructor);
12458 } else if (Constructor->isCopyConstructor()) {
12459 DefineImplicitCopyConstructor(Loc, Constructor);
12460 } else if (Constructor->isMoveConstructor()) {
12461 DefineImplicitMoveConstructor(Loc, Constructor);
12462 }
12463 } else if (Constructor->getInheritedConstructor()) {
12464 DefineInheritingConstructor(Loc, Constructor);
12465 }
12466 } else if (CXXDestructorDecl *Destructor =
12467 dyn_cast<CXXDestructorDecl>(Func)) {
12468 Destructor = cast<CXXDestructorDecl>(Destructor->getFirstDecl());
12469 if (Destructor->isDefaulted() && !Destructor->isDeleted()) {
12470 if (Destructor->isTrivial() && !Destructor->hasAttr<DLLExportAttr>())
12471 return;
12472 DefineImplicitDestructor(Loc, Destructor);
12473 }
12474 if (Destructor->isVirtual() && getLangOpts().AppleKext)
12475 MarkVTableUsed(Loc, Destructor->getParent());
12476 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(Func)) {
12477 if (MethodDecl->isOverloadedOperator() &&
12478 MethodDecl->getOverloadedOperator() == OO_Equal) {
12479 MethodDecl = cast<CXXMethodDecl>(MethodDecl->getFirstDecl());
12480 if (MethodDecl->isDefaulted() && !MethodDecl->isDeleted()) {
12481 if (MethodDecl->isCopyAssignmentOperator())
12482 DefineImplicitCopyAssignment(Loc, MethodDecl);
12483 else
12484 DefineImplicitMoveAssignment(Loc, MethodDecl);
12485 }
12486 } else if (isa<CXXConversionDecl>(MethodDecl) &&
12487 MethodDecl->getParent()->isLambda()) {
12488 CXXConversionDecl *Conversion =
12489 cast<CXXConversionDecl>(MethodDecl->getFirstDecl());
12490 if (Conversion->isLambdaToBlockPointerConversion())
12491 DefineImplicitLambdaToBlockPointerConversion(Loc, Conversion);
12492 else
12493 DefineImplicitLambdaToFunctionPointerConversion(Loc, Conversion);
12494 } else if (MethodDecl->isVirtual() && getLangOpts().AppleKext)
12495 MarkVTableUsed(Loc, MethodDecl->getParent());
12496 }
12497
12498 // Recursive functions should be marked when used from another function.
12499 // FIXME: Is this really right?
12500 if (CurContext == Func) return;
12501
12502 // Resolve the exception specification for any function which is
12503 // used: CodeGen will need it.
12504 const FunctionProtoType *FPT = Func->getType()->getAs<FunctionProtoType>();
12505 if (FPT && isUnresolvedExceptionSpec(FPT->getExceptionSpecType()))
12506 ResolveExceptionSpec(Loc, FPT);
12507
12508 if (!OdrUse) return;
12509
12510 // Implicit instantiation of function templates and member functions of
12511 // class templates.
12512 if (Func->isImplicitlyInstantiable()) {
12513 bool AlreadyInstantiated = false;
12514 SourceLocation PointOfInstantiation = Loc;
12515 if (FunctionTemplateSpecializationInfo *SpecInfo
12516 = Func->getTemplateSpecializationInfo()) {
12517 if (SpecInfo->getPointOfInstantiation().isInvalid())
12518 SpecInfo->setPointOfInstantiation(Loc);
12519 else if (SpecInfo->getTemplateSpecializationKind()
12520 == TSK_ImplicitInstantiation) {
12521 AlreadyInstantiated = true;
12522 PointOfInstantiation = SpecInfo->getPointOfInstantiation();
12523 }
12524 } else if (MemberSpecializationInfo *MSInfo
12525 = Func->getMemberSpecializationInfo()) {
12526 if (MSInfo->getPointOfInstantiation().isInvalid())
12527 MSInfo->setPointOfInstantiation(Loc);
12528 else if (MSInfo->getTemplateSpecializationKind()
12529 == TSK_ImplicitInstantiation) {
12530 AlreadyInstantiated = true;
12531 PointOfInstantiation = MSInfo->getPointOfInstantiation();
12532 }
12533 }
12534
12535 if (!AlreadyInstantiated || Func->isConstexpr()) {
12536 if (isa<CXXRecordDecl>(Func->getDeclContext()) &&
12537 cast<CXXRecordDecl>(Func->getDeclContext())->isLocalClass() &&
12538 ActiveTemplateInstantiations.size())
12539 PendingLocalImplicitInstantiations.push_back(
12540 std::make_pair(Func, PointOfInstantiation));
12541 else if (Func->isConstexpr())
12542 // Do not defer instantiations of constexpr functions, to avoid the
12543 // expression evaluator needing to call back into Sema if it sees a
12544 // call to such a function.
12545 InstantiateFunctionDefinition(PointOfInstantiation, Func);
12546 else {
12547 PendingInstantiations.push_back(std::make_pair(Func,
12548 PointOfInstantiation));
12549 // Notify the consumer that a function was implicitly instantiated.
12550 Consumer.HandleCXXImplicitFunctionInstantiation(Func);
12551 }
12552 }
12553 } else {
12554 // Walk redefinitions, as some of them may be instantiable.
12555 for (auto i : Func->redecls()) {
12556 if (!i->isUsed(false) && i->isImplicitlyInstantiable())
12557 MarkFunctionReferenced(Loc, i);
12558 }
12559 }
12560
12561 // Keep track of used but undefined functions.
12562 if (!Func->isDefined()) {
12563 if (mightHaveNonExternalLinkage(Func))
12564 UndefinedButUsed.insert(std::make_pair(Func->getCanonicalDecl(), Loc));
12565 else if (Func->getMostRecentDecl()->isInlined() &&
12566 !LangOpts.GNUInline &&
12567 !Func->getMostRecentDecl()->hasAttr<GNUInlineAttr>())
12568 UndefinedButUsed.insert(std::make_pair(Func->getCanonicalDecl(), Loc));
12569 }
12570
12571 // Normally the most current decl is marked used while processing the use and
12572 // any subsequent decls are marked used by decl merging. This fails with
12573 // template instantiation since marking can happen at the end of the file
12574 // and, because of the two phase lookup, this function is called with at
12575 // decl in the middle of a decl chain. We loop to maintain the invariant
12576 // that once a decl is used, all decls after it are also used.
12577 for (FunctionDecl *F = Func->getMostRecentDecl();; F = F->getPreviousDecl()) {
12578 F->markUsed(Context);
12579 if (F == Func)
12580 break;
12581 }
12582 }
12583
12584 static void
diagnoseUncapturableValueReference(Sema & S,SourceLocation loc,VarDecl * var,DeclContext * DC)12585 diagnoseUncapturableValueReference(Sema &S, SourceLocation loc,
12586 VarDecl *var, DeclContext *DC) {
12587 DeclContext *VarDC = var->getDeclContext();
12588
12589 // If the parameter still belongs to the translation unit, then
12590 // we're actually just using one parameter in the declaration of
12591 // the next.
12592 if (isa<ParmVarDecl>(var) &&
12593 isa<TranslationUnitDecl>(VarDC))
12594 return;
12595
12596 // For C code, don't diagnose about capture if we're not actually in code
12597 // right now; it's impossible to write a non-constant expression outside of
12598 // function context, so we'll get other (more useful) diagnostics later.
12599 //
12600 // For C++, things get a bit more nasty... it would be nice to suppress this
12601 // diagnostic for certain cases like using a local variable in an array bound
12602 // for a member of a local class, but the correct predicate is not obvious.
12603 if (!S.getLangOpts().CPlusPlus && !S.CurContext->isFunctionOrMethod())
12604 return;
12605
12606 if (isa<CXXMethodDecl>(VarDC) &&
12607 cast<CXXRecordDecl>(VarDC->getParent())->isLambda()) {
12608 S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_lambda)
12609 << var->getIdentifier();
12610 } else if (FunctionDecl *fn = dyn_cast<FunctionDecl>(VarDC)) {
12611 S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_function)
12612 << var->getIdentifier() << fn->getDeclName();
12613 } else if (isa<BlockDecl>(VarDC)) {
12614 S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_block)
12615 << var->getIdentifier();
12616 } else {
12617 // FIXME: Is there any other context where a local variable can be
12618 // declared?
12619 S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_context)
12620 << var->getIdentifier();
12621 }
12622
12623 S.Diag(var->getLocation(), diag::note_entity_declared_at)
12624 << var->getIdentifier();
12625
12626 // FIXME: Add additional diagnostic info about class etc. which prevents
12627 // capture.
12628 }
12629
12630
isVariableAlreadyCapturedInScopeInfo(CapturingScopeInfo * CSI,VarDecl * Var,bool & SubCapturesAreNested,QualType & CaptureType,QualType & DeclRefType)12631 static bool isVariableAlreadyCapturedInScopeInfo(CapturingScopeInfo *CSI, VarDecl *Var,
12632 bool &SubCapturesAreNested,
12633 QualType &CaptureType,
12634 QualType &DeclRefType) {
12635 // Check whether we've already captured it.
12636 if (CSI->CaptureMap.count(Var)) {
12637 // If we found a capture, any subcaptures are nested.
12638 SubCapturesAreNested = true;
12639
12640 // Retrieve the capture type for this variable.
12641 CaptureType = CSI->getCapture(Var).getCaptureType();
12642
12643 // Compute the type of an expression that refers to this variable.
12644 DeclRefType = CaptureType.getNonReferenceType();
12645
12646 // Similarly to mutable captures in lambda, all the OpenMP captures by copy
12647 // are mutable in the sense that user can change their value - they are
12648 // private instances of the captured declarations.
12649 const CapturingScopeInfo::Capture &Cap = CSI->getCapture(Var);
12650 if (Cap.isCopyCapture() &&
12651 !(isa<LambdaScopeInfo>(CSI) && cast<LambdaScopeInfo>(CSI)->Mutable) &&
12652 !(isa<CapturedRegionScopeInfo>(CSI) &&
12653 cast<CapturedRegionScopeInfo>(CSI)->CapRegionKind == CR_OpenMP))
12654 DeclRefType.addConst();
12655 return true;
12656 }
12657 return false;
12658 }
12659
12660 // Only block literals, captured statements, and lambda expressions can
12661 // capture; other scopes don't work.
getParentOfCapturingContextOrNull(DeclContext * DC,VarDecl * Var,SourceLocation Loc,const bool Diagnose,Sema & S)12662 static DeclContext *getParentOfCapturingContextOrNull(DeclContext *DC, VarDecl *Var,
12663 SourceLocation Loc,
12664 const bool Diagnose, Sema &S) {
12665 if (isa<BlockDecl>(DC) || isa<CapturedDecl>(DC) || isLambdaCallOperator(DC))
12666 return getLambdaAwareParentOfDeclContext(DC);
12667 else if (Var->hasLocalStorage()) {
12668 if (Diagnose)
12669 diagnoseUncapturableValueReference(S, Loc, Var, DC);
12670 }
12671 return nullptr;
12672 }
12673
12674 // Certain capturing entities (lambdas, blocks etc.) are not allowed to capture
12675 // certain types of variables (unnamed, variably modified types etc.)
12676 // so check for eligibility.
isVariableCapturable(CapturingScopeInfo * CSI,VarDecl * Var,SourceLocation Loc,const bool Diagnose,Sema & S)12677 static bool isVariableCapturable(CapturingScopeInfo *CSI, VarDecl *Var,
12678 SourceLocation Loc,
12679 const bool Diagnose, Sema &S) {
12680
12681 bool IsBlock = isa<BlockScopeInfo>(CSI);
12682 bool IsLambda = isa<LambdaScopeInfo>(CSI);
12683
12684 // Lambdas are not allowed to capture unnamed variables
12685 // (e.g. anonymous unions).
12686 // FIXME: The C++11 rule don't actually state this explicitly, but I'm
12687 // assuming that's the intent.
12688 if (IsLambda && !Var->getDeclName()) {
12689 if (Diagnose) {
12690 S.Diag(Loc, diag::err_lambda_capture_anonymous_var);
12691 S.Diag(Var->getLocation(), diag::note_declared_at);
12692 }
12693 return false;
12694 }
12695
12696 // Prohibit variably-modified types in blocks; they're difficult to deal with.
12697 if (Var->getType()->isVariablyModifiedType() && IsBlock) {
12698 if (Diagnose) {
12699 S.Diag(Loc, diag::err_ref_vm_type);
12700 S.Diag(Var->getLocation(), diag::note_previous_decl)
12701 << Var->getDeclName();
12702 }
12703 return false;
12704 }
12705 // Prohibit structs with flexible array members too.
12706 // We cannot capture what is in the tail end of the struct.
12707 if (const RecordType *VTTy = Var->getType()->getAs<RecordType>()) {
12708 if (VTTy->getDecl()->hasFlexibleArrayMember()) {
12709 if (Diagnose) {
12710 if (IsBlock)
12711 S.Diag(Loc, diag::err_ref_flexarray_type);
12712 else
12713 S.Diag(Loc, diag::err_lambda_capture_flexarray_type)
12714 << Var->getDeclName();
12715 S.Diag(Var->getLocation(), diag::note_previous_decl)
12716 << Var->getDeclName();
12717 }
12718 return false;
12719 }
12720 }
12721 const bool HasBlocksAttr = Var->hasAttr<BlocksAttr>();
12722 // Lambdas and captured statements are not allowed to capture __block
12723 // variables; they don't support the expected semantics.
12724 if (HasBlocksAttr && (IsLambda || isa<CapturedRegionScopeInfo>(CSI))) {
12725 if (Diagnose) {
12726 S.Diag(Loc, diag::err_capture_block_variable)
12727 << Var->getDeclName() << !IsLambda;
12728 S.Diag(Var->getLocation(), diag::note_previous_decl)
12729 << Var->getDeclName();
12730 }
12731 return false;
12732 }
12733
12734 return true;
12735 }
12736
12737 // Returns true if the capture by block was successful.
captureInBlock(BlockScopeInfo * BSI,VarDecl * Var,SourceLocation Loc,const bool BuildAndDiagnose,QualType & CaptureType,QualType & DeclRefType,const bool Nested,Sema & S)12738 static bool captureInBlock(BlockScopeInfo *BSI, VarDecl *Var,
12739 SourceLocation Loc,
12740 const bool BuildAndDiagnose,
12741 QualType &CaptureType,
12742 QualType &DeclRefType,
12743 const bool Nested,
12744 Sema &S) {
12745 Expr *CopyExpr = nullptr;
12746 bool ByRef = false;
12747
12748 // Blocks are not allowed to capture arrays.
12749 if (CaptureType->isArrayType()) {
12750 if (BuildAndDiagnose) {
12751 S.Diag(Loc, diag::err_ref_array_type);
12752 S.Diag(Var->getLocation(), diag::note_previous_decl)
12753 << Var->getDeclName();
12754 }
12755 return false;
12756 }
12757
12758 // Forbid the block-capture of autoreleasing variables.
12759 if (CaptureType.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) {
12760 if (BuildAndDiagnose) {
12761 S.Diag(Loc, diag::err_arc_autoreleasing_capture)
12762 << /*block*/ 0;
12763 S.Diag(Var->getLocation(), diag::note_previous_decl)
12764 << Var->getDeclName();
12765 }
12766 return false;
12767 }
12768 const bool HasBlocksAttr = Var->hasAttr<BlocksAttr>();
12769 if (HasBlocksAttr || CaptureType->isReferenceType()) {
12770 // Block capture by reference does not change the capture or
12771 // declaration reference types.
12772 ByRef = true;
12773 } else {
12774 // Block capture by copy introduces 'const'.
12775 CaptureType = CaptureType.getNonReferenceType().withConst();
12776 DeclRefType = CaptureType;
12777
12778 if (S.getLangOpts().CPlusPlus && BuildAndDiagnose) {
12779 if (const RecordType *Record = DeclRefType->getAs<RecordType>()) {
12780 // The capture logic needs the destructor, so make sure we mark it.
12781 // Usually this is unnecessary because most local variables have
12782 // their destructors marked at declaration time, but parameters are
12783 // an exception because it's technically only the call site that
12784 // actually requires the destructor.
12785 if (isa<ParmVarDecl>(Var))
12786 S.FinalizeVarWithDestructor(Var, Record);
12787
12788 // Enter a new evaluation context to insulate the copy
12789 // full-expression.
12790 EnterExpressionEvaluationContext scope(S, S.PotentiallyEvaluated);
12791
12792 // According to the blocks spec, the capture of a variable from
12793 // the stack requires a const copy constructor. This is not true
12794 // of the copy/move done to move a __block variable to the heap.
12795 Expr *DeclRef = new (S.Context) DeclRefExpr(Var, Nested,
12796 DeclRefType.withConst(),
12797 VK_LValue, Loc);
12798
12799 ExprResult Result
12800 = S.PerformCopyInitialization(
12801 InitializedEntity::InitializeBlock(Var->getLocation(),
12802 CaptureType, false),
12803 Loc, DeclRef);
12804
12805 // Build a full-expression copy expression if initialization
12806 // succeeded and used a non-trivial constructor. Recover from
12807 // errors by pretending that the copy isn't necessary.
12808 if (!Result.isInvalid() &&
12809 !cast<CXXConstructExpr>(Result.get())->getConstructor()
12810 ->isTrivial()) {
12811 Result = S.MaybeCreateExprWithCleanups(Result);
12812 CopyExpr = Result.get();
12813 }
12814 }
12815 }
12816 }
12817
12818 // Actually capture the variable.
12819 if (BuildAndDiagnose)
12820 BSI->addCapture(Var, HasBlocksAttr, ByRef, Nested, Loc,
12821 SourceLocation(), CaptureType, CopyExpr);
12822
12823 return true;
12824
12825 }
12826
12827
12828 /// \brief Capture the given variable in the captured region.
captureInCapturedRegion(CapturedRegionScopeInfo * RSI,VarDecl * Var,SourceLocation Loc,const bool BuildAndDiagnose,QualType & CaptureType,QualType & DeclRefType,const bool RefersToCapturedVariable,Sema & S)12829 static bool captureInCapturedRegion(CapturedRegionScopeInfo *RSI,
12830 VarDecl *Var,
12831 SourceLocation Loc,
12832 const bool BuildAndDiagnose,
12833 QualType &CaptureType,
12834 QualType &DeclRefType,
12835 const bool RefersToCapturedVariable,
12836 Sema &S) {
12837
12838 // By default, capture variables by reference.
12839 bool ByRef = true;
12840 // Using an LValue reference type is consistent with Lambdas (see below).
12841 if (S.getLangOpts().OpenMP) {
12842 ByRef = S.IsOpenMPCapturedByRef(Var, RSI);
12843 if (S.IsOpenMPCapturedVar(Var))
12844 DeclRefType = DeclRefType.getUnqualifiedType();
12845 }
12846
12847 if (ByRef)
12848 CaptureType = S.Context.getLValueReferenceType(DeclRefType);
12849 else
12850 CaptureType = DeclRefType;
12851
12852 Expr *CopyExpr = nullptr;
12853 if (BuildAndDiagnose) {
12854 // The current implementation assumes that all variables are captured
12855 // by references. Since there is no capture by copy, no expression
12856 // evaluation will be needed.
12857 RecordDecl *RD = RSI->TheRecordDecl;
12858
12859 FieldDecl *Field
12860 = FieldDecl::Create(S.Context, RD, Loc, Loc, nullptr, CaptureType,
12861 S.Context.getTrivialTypeSourceInfo(CaptureType, Loc),
12862 nullptr, false, ICIS_NoInit);
12863 Field->setImplicit(true);
12864 Field->setAccess(AS_private);
12865 RD->addDecl(Field);
12866
12867 CopyExpr = new (S.Context) DeclRefExpr(Var, RefersToCapturedVariable,
12868 DeclRefType, VK_LValue, Loc);
12869 Var->setReferenced(true);
12870 Var->markUsed(S.Context);
12871 }
12872
12873 // Actually capture the variable.
12874 if (BuildAndDiagnose)
12875 RSI->addCapture(Var, /*isBlock*/false, ByRef, RefersToCapturedVariable, Loc,
12876 SourceLocation(), CaptureType, CopyExpr);
12877
12878
12879 return true;
12880 }
12881
12882 /// \brief Create a field within the lambda class for the variable
12883 /// being captured.
addAsFieldToClosureType(Sema & S,LambdaScopeInfo * LSI,VarDecl * Var,QualType FieldType,QualType DeclRefType,SourceLocation Loc,bool RefersToCapturedVariable)12884 static void addAsFieldToClosureType(Sema &S, LambdaScopeInfo *LSI, VarDecl *Var,
12885 QualType FieldType, QualType DeclRefType,
12886 SourceLocation Loc,
12887 bool RefersToCapturedVariable) {
12888 CXXRecordDecl *Lambda = LSI->Lambda;
12889
12890 // Build the non-static data member.
12891 FieldDecl *Field
12892 = FieldDecl::Create(S.Context, Lambda, Loc, Loc, nullptr, FieldType,
12893 S.Context.getTrivialTypeSourceInfo(FieldType, Loc),
12894 nullptr, false, ICIS_NoInit);
12895 Field->setImplicit(true);
12896 Field->setAccess(AS_private);
12897 Lambda->addDecl(Field);
12898 }
12899
12900 /// \brief Capture the given variable in the lambda.
captureInLambda(LambdaScopeInfo * LSI,VarDecl * Var,SourceLocation Loc,const bool BuildAndDiagnose,QualType & CaptureType,QualType & DeclRefType,const bool RefersToCapturedVariable,const Sema::TryCaptureKind Kind,SourceLocation EllipsisLoc,const bool IsTopScope,Sema & S)12901 static bool captureInLambda(LambdaScopeInfo *LSI,
12902 VarDecl *Var,
12903 SourceLocation Loc,
12904 const bool BuildAndDiagnose,
12905 QualType &CaptureType,
12906 QualType &DeclRefType,
12907 const bool RefersToCapturedVariable,
12908 const Sema::TryCaptureKind Kind,
12909 SourceLocation EllipsisLoc,
12910 const bool IsTopScope,
12911 Sema &S) {
12912
12913 // Determine whether we are capturing by reference or by value.
12914 bool ByRef = false;
12915 if (IsTopScope && Kind != Sema::TryCapture_Implicit) {
12916 ByRef = (Kind == Sema::TryCapture_ExplicitByRef);
12917 } else {
12918 ByRef = (LSI->ImpCaptureStyle == LambdaScopeInfo::ImpCap_LambdaByref);
12919 }
12920
12921 // Compute the type of the field that will capture this variable.
12922 if (ByRef) {
12923 // C++11 [expr.prim.lambda]p15:
12924 // An entity is captured by reference if it is implicitly or
12925 // explicitly captured but not captured by copy. It is
12926 // unspecified whether additional unnamed non-static data
12927 // members are declared in the closure type for entities
12928 // captured by reference.
12929 //
12930 // FIXME: It is not clear whether we want to build an lvalue reference
12931 // to the DeclRefType or to CaptureType.getNonReferenceType(). GCC appears
12932 // to do the former, while EDG does the latter. Core issue 1249 will
12933 // clarify, but for now we follow GCC because it's a more permissive and
12934 // easily defensible position.
12935 CaptureType = S.Context.getLValueReferenceType(DeclRefType);
12936 } else {
12937 // C++11 [expr.prim.lambda]p14:
12938 // For each entity captured by copy, an unnamed non-static
12939 // data member is declared in the closure type. The
12940 // declaration order of these members is unspecified. The type
12941 // of such a data member is the type of the corresponding
12942 // captured entity if the entity is not a reference to an
12943 // object, or the referenced type otherwise. [Note: If the
12944 // captured entity is a reference to a function, the
12945 // corresponding data member is also a reference to a
12946 // function. - end note ]
12947 if (const ReferenceType *RefType = CaptureType->getAs<ReferenceType>()){
12948 if (!RefType->getPointeeType()->isFunctionType())
12949 CaptureType = RefType->getPointeeType();
12950 }
12951
12952 // Forbid the lambda copy-capture of autoreleasing variables.
12953 if (CaptureType.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) {
12954 if (BuildAndDiagnose) {
12955 S.Diag(Loc, diag::err_arc_autoreleasing_capture) << /*lambda*/ 1;
12956 S.Diag(Var->getLocation(), diag::note_previous_decl)
12957 << Var->getDeclName();
12958 }
12959 return false;
12960 }
12961
12962 // Make sure that by-copy captures are of a complete and non-abstract type.
12963 if (BuildAndDiagnose) {
12964 if (!CaptureType->isDependentType() &&
12965 S.RequireCompleteType(Loc, CaptureType,
12966 diag::err_capture_of_incomplete_type,
12967 Var->getDeclName()))
12968 return false;
12969
12970 if (S.RequireNonAbstractType(Loc, CaptureType,
12971 diag::err_capture_of_abstract_type))
12972 return false;
12973 }
12974 }
12975
12976 // Capture this variable in the lambda.
12977 if (BuildAndDiagnose)
12978 addAsFieldToClosureType(S, LSI, Var, CaptureType, DeclRefType, Loc,
12979 RefersToCapturedVariable);
12980
12981 // Compute the type of a reference to this captured variable.
12982 if (ByRef)
12983 DeclRefType = CaptureType.getNonReferenceType();
12984 else {
12985 // C++ [expr.prim.lambda]p5:
12986 // The closure type for a lambda-expression has a public inline
12987 // function call operator [...]. This function call operator is
12988 // declared const (9.3.1) if and only if the lambda-expression’s
12989 // parameter-declaration-clause is not followed by mutable.
12990 DeclRefType = CaptureType.getNonReferenceType();
12991 if (!LSI->Mutable && !CaptureType->isReferenceType())
12992 DeclRefType.addConst();
12993 }
12994
12995 // Add the capture.
12996 if (BuildAndDiagnose)
12997 LSI->addCapture(Var, /*IsBlock=*/false, ByRef, RefersToCapturedVariable,
12998 Loc, EllipsisLoc, CaptureType, /*CopyExpr=*/nullptr);
12999
13000 return true;
13001 }
13002
tryCaptureVariable(VarDecl * Var,SourceLocation ExprLoc,TryCaptureKind Kind,SourceLocation EllipsisLoc,bool BuildAndDiagnose,QualType & CaptureType,QualType & DeclRefType,const unsigned * const FunctionScopeIndexToStopAt)13003 bool Sema::tryCaptureVariable(
13004 VarDecl *Var, SourceLocation ExprLoc, TryCaptureKind Kind,
13005 SourceLocation EllipsisLoc, bool BuildAndDiagnose, QualType &CaptureType,
13006 QualType &DeclRefType, const unsigned *const FunctionScopeIndexToStopAt) {
13007 // An init-capture is notionally from the context surrounding its
13008 // declaration, but its parent DC is the lambda class.
13009 DeclContext *VarDC = Var->getDeclContext();
13010 if (Var->isInitCapture())
13011 VarDC = VarDC->getParent();
13012
13013 DeclContext *DC = CurContext;
13014 const unsigned MaxFunctionScopesIndex = FunctionScopeIndexToStopAt
13015 ? *FunctionScopeIndexToStopAt : FunctionScopes.size() - 1;
13016 // We need to sync up the Declaration Context with the
13017 // FunctionScopeIndexToStopAt
13018 if (FunctionScopeIndexToStopAt) {
13019 unsigned FSIndex = FunctionScopes.size() - 1;
13020 while (FSIndex != MaxFunctionScopesIndex) {
13021 DC = getLambdaAwareParentOfDeclContext(DC);
13022 --FSIndex;
13023 }
13024 }
13025
13026
13027 // If the variable is declared in the current context, there is no need to
13028 // capture it.
13029 if (VarDC == DC) return true;
13030
13031 // Capture global variables if it is required to use private copy of this
13032 // variable.
13033 bool IsGlobal = !Var->hasLocalStorage();
13034 if (IsGlobal && !(LangOpts.OpenMP && IsOpenMPCapturedVar(Var)))
13035 return true;
13036
13037 // Walk up the stack to determine whether we can capture the variable,
13038 // performing the "simple" checks that don't depend on type. We stop when
13039 // we've either hit the declared scope of the variable or find an existing
13040 // capture of that variable. We start from the innermost capturing-entity
13041 // (the DC) and ensure that all intervening capturing-entities
13042 // (blocks/lambdas etc.) between the innermost capturer and the variable`s
13043 // declcontext can either capture the variable or have already captured
13044 // the variable.
13045 CaptureType = Var->getType();
13046 DeclRefType = CaptureType.getNonReferenceType();
13047 bool Nested = false;
13048 bool Explicit = (Kind != TryCapture_Implicit);
13049 unsigned FunctionScopesIndex = MaxFunctionScopesIndex;
13050 unsigned OpenMPLevel = 0;
13051 do {
13052 // Only block literals, captured statements, and lambda expressions can
13053 // capture; other scopes don't work.
13054 DeclContext *ParentDC = getParentOfCapturingContextOrNull(DC, Var,
13055 ExprLoc,
13056 BuildAndDiagnose,
13057 *this);
13058 // We need to check for the parent *first* because, if we *have*
13059 // private-captured a global variable, we need to recursively capture it in
13060 // intermediate blocks, lambdas, etc.
13061 if (!ParentDC) {
13062 if (IsGlobal) {
13063 FunctionScopesIndex = MaxFunctionScopesIndex - 1;
13064 break;
13065 }
13066 return true;
13067 }
13068
13069 FunctionScopeInfo *FSI = FunctionScopes[FunctionScopesIndex];
13070 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FSI);
13071
13072
13073 // Check whether we've already captured it.
13074 if (isVariableAlreadyCapturedInScopeInfo(CSI, Var, Nested, CaptureType,
13075 DeclRefType))
13076 break;
13077 // If we are instantiating a generic lambda call operator body,
13078 // we do not want to capture new variables. What was captured
13079 // during either a lambdas transformation or initial parsing
13080 // should be used.
13081 if (isGenericLambdaCallOperatorSpecialization(DC)) {
13082 if (BuildAndDiagnose) {
13083 LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(CSI);
13084 if (LSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_None) {
13085 Diag(ExprLoc, diag::err_lambda_impcap) << Var->getDeclName();
13086 Diag(Var->getLocation(), diag::note_previous_decl)
13087 << Var->getDeclName();
13088 Diag(LSI->Lambda->getLocStart(), diag::note_lambda_decl);
13089 } else
13090 diagnoseUncapturableValueReference(*this, ExprLoc, Var, DC);
13091 }
13092 return true;
13093 }
13094 // Certain capturing entities (lambdas, blocks etc.) are not allowed to capture
13095 // certain types of variables (unnamed, variably modified types etc.)
13096 // so check for eligibility.
13097 if (!isVariableCapturable(CSI, Var, ExprLoc, BuildAndDiagnose, *this))
13098 return true;
13099
13100 // Try to capture variable-length arrays types.
13101 if (Var->getType()->isVariablyModifiedType()) {
13102 // We're going to walk down into the type and look for VLA
13103 // expressions.
13104 QualType QTy = Var->getType();
13105 if (ParmVarDecl *PVD = dyn_cast_or_null<ParmVarDecl>(Var))
13106 QTy = PVD->getOriginalType();
13107 do {
13108 const Type *Ty = QTy.getTypePtr();
13109 switch (Ty->getTypeClass()) {
13110 #define TYPE(Class, Base)
13111 #define ABSTRACT_TYPE(Class, Base)
13112 #define NON_CANONICAL_TYPE(Class, Base)
13113 #define DEPENDENT_TYPE(Class, Base) case Type::Class:
13114 #define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base)
13115 #include "clang/AST/TypeNodes.def"
13116 QTy = QualType();
13117 break;
13118 // These types are never variably-modified.
13119 case Type::Builtin:
13120 case Type::Complex:
13121 case Type::Vector:
13122 case Type::ExtVector:
13123 case Type::Record:
13124 case Type::Enum:
13125 case Type::Elaborated:
13126 case Type::TemplateSpecialization:
13127 case Type::ObjCObject:
13128 case Type::ObjCInterface:
13129 case Type::ObjCObjectPointer:
13130 llvm_unreachable("type class is never variably-modified!");
13131 case Type::Adjusted:
13132 QTy = cast<AdjustedType>(Ty)->getOriginalType();
13133 break;
13134 case Type::Decayed:
13135 QTy = cast<DecayedType>(Ty)->getPointeeType();
13136 break;
13137 case Type::Pointer:
13138 QTy = cast<PointerType>(Ty)->getPointeeType();
13139 break;
13140 case Type::BlockPointer:
13141 QTy = cast<BlockPointerType>(Ty)->getPointeeType();
13142 break;
13143 case Type::LValueReference:
13144 case Type::RValueReference:
13145 QTy = cast<ReferenceType>(Ty)->getPointeeType();
13146 break;
13147 case Type::MemberPointer:
13148 QTy = cast<MemberPointerType>(Ty)->getPointeeType();
13149 break;
13150 case Type::ConstantArray:
13151 case Type::IncompleteArray:
13152 // Losing element qualification here is fine.
13153 QTy = cast<ArrayType>(Ty)->getElementType();
13154 break;
13155 case Type::VariableArray: {
13156 // Losing element qualification here is fine.
13157 const VariableArrayType *VAT = cast<VariableArrayType>(Ty);
13158
13159 // Unknown size indication requires no size computation.
13160 // Otherwise, evaluate and record it.
13161 if (auto Size = VAT->getSizeExpr()) {
13162 if (!CSI->isVLATypeCaptured(VAT)) {
13163 RecordDecl *CapRecord = nullptr;
13164 if (auto LSI = dyn_cast<LambdaScopeInfo>(CSI)) {
13165 CapRecord = LSI->Lambda;
13166 } else if (auto CRSI = dyn_cast<CapturedRegionScopeInfo>(CSI)) {
13167 CapRecord = CRSI->TheRecordDecl;
13168 }
13169 if (CapRecord) {
13170 auto ExprLoc = Size->getExprLoc();
13171 auto SizeType = Context.getSizeType();
13172 // Build the non-static data member.
13173 auto Field = FieldDecl::Create(
13174 Context, CapRecord, ExprLoc, ExprLoc,
13175 /*Id*/ nullptr, SizeType, /*TInfo*/ nullptr,
13176 /*BW*/ nullptr, /*Mutable*/ false,
13177 /*InitStyle*/ ICIS_NoInit);
13178 Field->setImplicit(true);
13179 Field->setAccess(AS_private);
13180 Field->setCapturedVLAType(VAT);
13181 CapRecord->addDecl(Field);
13182
13183 CSI->addVLATypeCapture(ExprLoc, SizeType);
13184 }
13185 }
13186 }
13187 QTy = VAT->getElementType();
13188 break;
13189 }
13190 case Type::FunctionProto:
13191 case Type::FunctionNoProto:
13192 QTy = cast<FunctionType>(Ty)->getReturnType();
13193 break;
13194 case Type::Paren:
13195 case Type::TypeOf:
13196 case Type::UnaryTransform:
13197 case Type::Attributed:
13198 case Type::SubstTemplateTypeParm:
13199 case Type::PackExpansion:
13200 // Keep walking after single level desugaring.
13201 QTy = QTy.getSingleStepDesugaredType(getASTContext());
13202 break;
13203 case Type::Typedef:
13204 QTy = cast<TypedefType>(Ty)->desugar();
13205 break;
13206 case Type::Decltype:
13207 QTy = cast<DecltypeType>(Ty)->desugar();
13208 break;
13209 case Type::Auto:
13210 QTy = cast<AutoType>(Ty)->getDeducedType();
13211 break;
13212 case Type::TypeOfExpr:
13213 QTy = cast<TypeOfExprType>(Ty)->getUnderlyingExpr()->getType();
13214 break;
13215 case Type::Atomic:
13216 QTy = cast<AtomicType>(Ty)->getValueType();
13217 break;
13218 }
13219 } while (!QTy.isNull() && QTy->isVariablyModifiedType());
13220 }
13221
13222 if (getLangOpts().OpenMP) {
13223 if (auto *RSI = dyn_cast<CapturedRegionScopeInfo>(CSI)) {
13224 // OpenMP private variables should not be captured in outer scope, so
13225 // just break here. Similarly, global variables that are captured in a
13226 // target region should not be captured outside the scope of the region.
13227 if (RSI->CapRegionKind == CR_OpenMP) {
13228 auto isTargetCap = isOpenMPTargetCapturedVar(Var, OpenMPLevel);
13229 // When we detect target captures we are looking from inside the
13230 // target region, therefore we need to propagate the capture from the
13231 // enclosing region. Therefore, the capture is not initially nested.
13232 if (isTargetCap)
13233 FunctionScopesIndex--;
13234
13235 if (isTargetCap || isOpenMPPrivateVar(Var, OpenMPLevel)) {
13236 Nested = !isTargetCap;
13237 DeclRefType = DeclRefType.getUnqualifiedType();
13238 CaptureType = Context.getLValueReferenceType(DeclRefType);
13239 break;
13240 }
13241 ++OpenMPLevel;
13242 }
13243 }
13244 }
13245 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_None && !Explicit) {
13246 // No capture-default, and this is not an explicit capture
13247 // so cannot capture this variable.
13248 if (BuildAndDiagnose) {
13249 Diag(ExprLoc, diag::err_lambda_impcap) << Var->getDeclName();
13250 Diag(Var->getLocation(), diag::note_previous_decl)
13251 << Var->getDeclName();
13252 Diag(cast<LambdaScopeInfo>(CSI)->Lambda->getLocStart(),
13253 diag::note_lambda_decl);
13254 // FIXME: If we error out because an outer lambda can not implicitly
13255 // capture a variable that an inner lambda explicitly captures, we
13256 // should have the inner lambda do the explicit capture - because
13257 // it makes for cleaner diagnostics later. This would purely be done
13258 // so that the diagnostic does not misleadingly claim that a variable
13259 // can not be captured by a lambda implicitly even though it is captured
13260 // explicitly. Suggestion:
13261 // - create const bool VariableCaptureWasInitiallyExplicit = Explicit
13262 // at the function head
13263 // - cache the StartingDeclContext - this must be a lambda
13264 // - captureInLambda in the innermost lambda the variable.
13265 }
13266 return true;
13267 }
13268
13269 FunctionScopesIndex--;
13270 DC = ParentDC;
13271 Explicit = false;
13272 } while (!VarDC->Equals(DC));
13273
13274 // Walk back down the scope stack, (e.g. from outer lambda to inner lambda)
13275 // computing the type of the capture at each step, checking type-specific
13276 // requirements, and adding captures if requested.
13277 // If the variable had already been captured previously, we start capturing
13278 // at the lambda nested within that one.
13279 for (unsigned I = ++FunctionScopesIndex, N = MaxFunctionScopesIndex + 1; I != N;
13280 ++I) {
13281 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[I]);
13282
13283 if (BlockScopeInfo *BSI = dyn_cast<BlockScopeInfo>(CSI)) {
13284 if (!captureInBlock(BSI, Var, ExprLoc,
13285 BuildAndDiagnose, CaptureType,
13286 DeclRefType, Nested, *this))
13287 return true;
13288 Nested = true;
13289 } else if (CapturedRegionScopeInfo *RSI = dyn_cast<CapturedRegionScopeInfo>(CSI)) {
13290 if (!captureInCapturedRegion(RSI, Var, ExprLoc,
13291 BuildAndDiagnose, CaptureType,
13292 DeclRefType, Nested, *this))
13293 return true;
13294 Nested = true;
13295 } else {
13296 LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(CSI);
13297 if (!captureInLambda(LSI, Var, ExprLoc,
13298 BuildAndDiagnose, CaptureType,
13299 DeclRefType, Nested, Kind, EllipsisLoc,
13300 /*IsTopScope*/I == N - 1, *this))
13301 return true;
13302 Nested = true;
13303 }
13304 }
13305 return false;
13306 }
13307
tryCaptureVariable(VarDecl * Var,SourceLocation Loc,TryCaptureKind Kind,SourceLocation EllipsisLoc)13308 bool Sema::tryCaptureVariable(VarDecl *Var, SourceLocation Loc,
13309 TryCaptureKind Kind, SourceLocation EllipsisLoc) {
13310 QualType CaptureType;
13311 QualType DeclRefType;
13312 return tryCaptureVariable(Var, Loc, Kind, EllipsisLoc,
13313 /*BuildAndDiagnose=*/true, CaptureType,
13314 DeclRefType, nullptr);
13315 }
13316
NeedToCaptureVariable(VarDecl * Var,SourceLocation Loc)13317 bool Sema::NeedToCaptureVariable(VarDecl *Var, SourceLocation Loc) {
13318 QualType CaptureType;
13319 QualType DeclRefType;
13320 return !tryCaptureVariable(Var, Loc, TryCapture_Implicit, SourceLocation(),
13321 /*BuildAndDiagnose=*/false, CaptureType,
13322 DeclRefType, nullptr);
13323 }
13324
getCapturedDeclRefType(VarDecl * Var,SourceLocation Loc)13325 QualType Sema::getCapturedDeclRefType(VarDecl *Var, SourceLocation Loc) {
13326 QualType CaptureType;
13327 QualType DeclRefType;
13328
13329 // Determine whether we can capture this variable.
13330 if (tryCaptureVariable(Var, Loc, TryCapture_Implicit, SourceLocation(),
13331 /*BuildAndDiagnose=*/false, CaptureType,
13332 DeclRefType, nullptr))
13333 return QualType();
13334
13335 return DeclRefType;
13336 }
13337
13338
13339
13340 // If either the type of the variable or the initializer is dependent,
13341 // return false. Otherwise, determine whether the variable is a constant
13342 // expression. Use this if you need to know if a variable that might or
13343 // might not be dependent is truly a constant expression.
IsVariableNonDependentAndAConstantExpression(VarDecl * Var,ASTContext & Context)13344 static inline bool IsVariableNonDependentAndAConstantExpression(VarDecl *Var,
13345 ASTContext &Context) {
13346
13347 if (Var->getType()->isDependentType())
13348 return false;
13349 const VarDecl *DefVD = nullptr;
13350 Var->getAnyInitializer(DefVD);
13351 if (!DefVD)
13352 return false;
13353 EvaluatedStmt *Eval = DefVD->ensureEvaluatedStmt();
13354 Expr *Init = cast<Expr>(Eval->Value);
13355 if (Init->isValueDependent())
13356 return false;
13357 return IsVariableAConstantExpression(Var, Context);
13358 }
13359
13360
UpdateMarkingForLValueToRValue(Expr * E)13361 void Sema::UpdateMarkingForLValueToRValue(Expr *E) {
13362 // Per C++11 [basic.def.odr], a variable is odr-used "unless it is
13363 // an object that satisfies the requirements for appearing in a
13364 // constant expression (5.19) and the lvalue-to-rvalue conversion (4.1)
13365 // is immediately applied." This function handles the lvalue-to-rvalue
13366 // conversion part.
13367 MaybeODRUseExprs.erase(E->IgnoreParens());
13368
13369 // If we are in a lambda, check if this DeclRefExpr or MemberExpr refers
13370 // to a variable that is a constant expression, and if so, identify it as
13371 // a reference to a variable that does not involve an odr-use of that
13372 // variable.
13373 if (LambdaScopeInfo *LSI = getCurLambda()) {
13374 Expr *SansParensExpr = E->IgnoreParens();
13375 VarDecl *Var = nullptr;
13376 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(SansParensExpr))
13377 Var = dyn_cast<VarDecl>(DRE->getFoundDecl());
13378 else if (MemberExpr *ME = dyn_cast<MemberExpr>(SansParensExpr))
13379 Var = dyn_cast<VarDecl>(ME->getMemberDecl());
13380
13381 if (Var && IsVariableNonDependentAndAConstantExpression(Var, Context))
13382 LSI->markVariableExprAsNonODRUsed(SansParensExpr);
13383 }
13384 }
13385
ActOnConstantExpression(ExprResult Res)13386 ExprResult Sema::ActOnConstantExpression(ExprResult Res) {
13387 Res = CorrectDelayedTyposInExpr(Res);
13388
13389 if (!Res.isUsable())
13390 return Res;
13391
13392 // If a constant-expression is a reference to a variable where we delay
13393 // deciding whether it is an odr-use, just assume we will apply the
13394 // lvalue-to-rvalue conversion. In the one case where this doesn't happen
13395 // (a non-type template argument), we have special handling anyway.
13396 UpdateMarkingForLValueToRValue(Res.get());
13397 return Res;
13398 }
13399
CleanupVarDeclMarking()13400 void Sema::CleanupVarDeclMarking() {
13401 for (Expr *E : MaybeODRUseExprs) {
13402 VarDecl *Var;
13403 SourceLocation Loc;
13404 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
13405 Var = cast<VarDecl>(DRE->getDecl());
13406 Loc = DRE->getLocation();
13407 } else if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
13408 Var = cast<VarDecl>(ME->getMemberDecl());
13409 Loc = ME->getMemberLoc();
13410 } else {
13411 llvm_unreachable("Unexpected expression");
13412 }
13413
13414 MarkVarDeclODRUsed(Var, Loc, *this,
13415 /*MaxFunctionScopeIndex Pointer*/ nullptr);
13416 }
13417
13418 MaybeODRUseExprs.clear();
13419 }
13420
13421
DoMarkVarDeclReferenced(Sema & SemaRef,SourceLocation Loc,VarDecl * Var,Expr * E)13422 static void DoMarkVarDeclReferenced(Sema &SemaRef, SourceLocation Loc,
13423 VarDecl *Var, Expr *E) {
13424 assert((!E || isa<DeclRefExpr>(E) || isa<MemberExpr>(E)) &&
13425 "Invalid Expr argument to DoMarkVarDeclReferenced");
13426 Var->setReferenced();
13427
13428 TemplateSpecializationKind TSK = Var->getTemplateSpecializationKind();
13429 bool MarkODRUsed = true;
13430
13431 // If the context is not potentially evaluated, this is not an odr-use and
13432 // does not trigger instantiation.
13433 if (!IsPotentiallyEvaluatedContext(SemaRef)) {
13434 if (SemaRef.isUnevaluatedContext())
13435 return;
13436
13437 // If we don't yet know whether this context is going to end up being an
13438 // evaluated context, and we're referencing a variable from an enclosing
13439 // scope, add a potential capture.
13440 //
13441 // FIXME: Is this necessary? These contexts are only used for default
13442 // arguments, where local variables can't be used.
13443 const bool RefersToEnclosingScope =
13444 (SemaRef.CurContext != Var->getDeclContext() &&
13445 Var->getDeclContext()->isFunctionOrMethod() && Var->hasLocalStorage());
13446 if (RefersToEnclosingScope) {
13447 if (LambdaScopeInfo *const LSI = SemaRef.getCurLambda()) {
13448 // If a variable could potentially be odr-used, defer marking it so
13449 // until we finish analyzing the full expression for any
13450 // lvalue-to-rvalue
13451 // or discarded value conversions that would obviate odr-use.
13452 // Add it to the list of potential captures that will be analyzed
13453 // later (ActOnFinishFullExpr) for eventual capture and odr-use marking
13454 // unless the variable is a reference that was initialized by a constant
13455 // expression (this will never need to be captured or odr-used).
13456 assert(E && "Capture variable should be used in an expression.");
13457 if (!Var->getType()->isReferenceType() ||
13458 !IsVariableNonDependentAndAConstantExpression(Var, SemaRef.Context))
13459 LSI->addPotentialCapture(E->IgnoreParens());
13460 }
13461 }
13462
13463 if (!isTemplateInstantiation(TSK))
13464 return;
13465
13466 // Instantiate, but do not mark as odr-used, variable templates.
13467 MarkODRUsed = false;
13468 }
13469
13470 VarTemplateSpecializationDecl *VarSpec =
13471 dyn_cast<VarTemplateSpecializationDecl>(Var);
13472 assert(!isa<VarTemplatePartialSpecializationDecl>(Var) &&
13473 "Can't instantiate a partial template specialization.");
13474
13475 // Perform implicit instantiation of static data members, static data member
13476 // templates of class templates, and variable template specializations. Delay
13477 // instantiations of variable templates, except for those that could be used
13478 // in a constant expression.
13479 if (isTemplateInstantiation(TSK)) {
13480 bool TryInstantiating = TSK == TSK_ImplicitInstantiation;
13481
13482 if (TryInstantiating && !isa<VarTemplateSpecializationDecl>(Var)) {
13483 if (Var->getPointOfInstantiation().isInvalid()) {
13484 // This is a modification of an existing AST node. Notify listeners.
13485 if (ASTMutationListener *L = SemaRef.getASTMutationListener())
13486 L->StaticDataMemberInstantiated(Var);
13487 } else if (!Var->isUsableInConstantExpressions(SemaRef.Context))
13488 // Don't bother trying to instantiate it again, unless we might need
13489 // its initializer before we get to the end of the TU.
13490 TryInstantiating = false;
13491 }
13492
13493 if (Var->getPointOfInstantiation().isInvalid())
13494 Var->setTemplateSpecializationKind(TSK, Loc);
13495
13496 if (TryInstantiating) {
13497 SourceLocation PointOfInstantiation = Var->getPointOfInstantiation();
13498 bool InstantiationDependent = false;
13499 bool IsNonDependent =
13500 VarSpec ? !TemplateSpecializationType::anyDependentTemplateArguments(
13501 VarSpec->getTemplateArgsInfo(), InstantiationDependent)
13502 : true;
13503
13504 // Do not instantiate specializations that are still type-dependent.
13505 if (IsNonDependent) {
13506 if (Var->isUsableInConstantExpressions(SemaRef.Context)) {
13507 // Do not defer instantiations of variables which could be used in a
13508 // constant expression.
13509 SemaRef.InstantiateVariableDefinition(PointOfInstantiation, Var);
13510 } else {
13511 SemaRef.PendingInstantiations
13512 .push_back(std::make_pair(Var, PointOfInstantiation));
13513 }
13514 }
13515 }
13516 }
13517
13518 if(!MarkODRUsed) return;
13519
13520 // Per C++11 [basic.def.odr], a variable is odr-used "unless it satisfies
13521 // the requirements for appearing in a constant expression (5.19) and, if
13522 // it is an object, the lvalue-to-rvalue conversion (4.1)
13523 // is immediately applied." We check the first part here, and
13524 // Sema::UpdateMarkingForLValueToRValue deals with the second part.
13525 // Note that we use the C++11 definition everywhere because nothing in
13526 // C++03 depends on whether we get the C++03 version correct. The second
13527 // part does not apply to references, since they are not objects.
13528 if (E && IsVariableAConstantExpression(Var, SemaRef.Context)) {
13529 // A reference initialized by a constant expression can never be
13530 // odr-used, so simply ignore it.
13531 if (!Var->getType()->isReferenceType())
13532 SemaRef.MaybeODRUseExprs.insert(E);
13533 } else
13534 MarkVarDeclODRUsed(Var, Loc, SemaRef,
13535 /*MaxFunctionScopeIndex ptr*/ nullptr);
13536 }
13537
13538 /// \brief Mark a variable referenced, and check whether it is odr-used
13539 /// (C++ [basic.def.odr]p2, C99 6.9p3). Note that this should not be
13540 /// used directly for normal expressions referring to VarDecl.
MarkVariableReferenced(SourceLocation Loc,VarDecl * Var)13541 void Sema::MarkVariableReferenced(SourceLocation Loc, VarDecl *Var) {
13542 DoMarkVarDeclReferenced(*this, Loc, Var, nullptr);
13543 }
13544
MarkExprReferenced(Sema & SemaRef,SourceLocation Loc,Decl * D,Expr * E,bool OdrUse)13545 static void MarkExprReferenced(Sema &SemaRef, SourceLocation Loc,
13546 Decl *D, Expr *E, bool OdrUse) {
13547 if (VarDecl *Var = dyn_cast<VarDecl>(D)) {
13548 DoMarkVarDeclReferenced(SemaRef, Loc, Var, E);
13549 return;
13550 }
13551
13552 SemaRef.MarkAnyDeclReferenced(Loc, D, OdrUse);
13553
13554 // If this is a call to a method via a cast, also mark the method in the
13555 // derived class used in case codegen can devirtualize the call.
13556 const MemberExpr *ME = dyn_cast<MemberExpr>(E);
13557 if (!ME)
13558 return;
13559 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(ME->getMemberDecl());
13560 if (!MD)
13561 return;
13562 // Only attempt to devirtualize if this is truly a virtual call.
13563 bool IsVirtualCall = MD->isVirtual() &&
13564 ME->performsVirtualDispatch(SemaRef.getLangOpts());
13565 if (!IsVirtualCall)
13566 return;
13567 const Expr *Base = ME->getBase();
13568 const CXXRecordDecl *MostDerivedClassDecl = Base->getBestDynamicClassType();
13569 if (!MostDerivedClassDecl)
13570 return;
13571 CXXMethodDecl *DM = MD->getCorrespondingMethodInClass(MostDerivedClassDecl);
13572 if (!DM || DM->isPure())
13573 return;
13574 SemaRef.MarkAnyDeclReferenced(Loc, DM, OdrUse);
13575 }
13576
13577 /// \brief Perform reference-marking and odr-use handling for a DeclRefExpr.
MarkDeclRefReferenced(DeclRefExpr * E)13578 void Sema::MarkDeclRefReferenced(DeclRefExpr *E) {
13579 // TODO: update this with DR# once a defect report is filed.
13580 // C++11 defect. The address of a pure member should not be an ODR use, even
13581 // if it's a qualified reference.
13582 bool OdrUse = true;
13583 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(E->getDecl()))
13584 if (Method->isVirtual())
13585 OdrUse = false;
13586 MarkExprReferenced(*this, E->getLocation(), E->getDecl(), E, OdrUse);
13587 }
13588
13589 /// \brief Perform reference-marking and odr-use handling for a MemberExpr.
MarkMemberReferenced(MemberExpr * E)13590 void Sema::MarkMemberReferenced(MemberExpr *E) {
13591 // C++11 [basic.def.odr]p2:
13592 // A non-overloaded function whose name appears as a potentially-evaluated
13593 // expression or a member of a set of candidate functions, if selected by
13594 // overload resolution when referred to from a potentially-evaluated
13595 // expression, is odr-used, unless it is a pure virtual function and its
13596 // name is not explicitly qualified.
13597 bool OdrUse = true;
13598 if (E->performsVirtualDispatch(getLangOpts())) {
13599 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(E->getMemberDecl()))
13600 if (Method->isPure())
13601 OdrUse = false;
13602 }
13603 SourceLocation Loc = E->getMemberLoc().isValid() ?
13604 E->getMemberLoc() : E->getLocStart();
13605 MarkExprReferenced(*this, Loc, E->getMemberDecl(), E, OdrUse);
13606 }
13607
13608 /// \brief Perform marking for a reference to an arbitrary declaration. It
13609 /// marks the declaration referenced, and performs odr-use checking for
13610 /// functions and variables. This method should not be used when building a
13611 /// normal expression which refers to a variable.
MarkAnyDeclReferenced(SourceLocation Loc,Decl * D,bool OdrUse)13612 void Sema::MarkAnyDeclReferenced(SourceLocation Loc, Decl *D, bool OdrUse) {
13613 if (OdrUse) {
13614 if (auto *VD = dyn_cast<VarDecl>(D)) {
13615 MarkVariableReferenced(Loc, VD);
13616 return;
13617 }
13618 }
13619 if (auto *FD = dyn_cast<FunctionDecl>(D)) {
13620 MarkFunctionReferenced(Loc, FD, OdrUse);
13621 return;
13622 }
13623 D->setReferenced();
13624 }
13625
13626 namespace {
13627 // Mark all of the declarations referenced
13628 // FIXME: Not fully implemented yet! We need to have a better understanding
13629 // of when we're entering
13630 class MarkReferencedDecls : public RecursiveASTVisitor<MarkReferencedDecls> {
13631 Sema &S;
13632 SourceLocation Loc;
13633
13634 public:
13635 typedef RecursiveASTVisitor<MarkReferencedDecls> Inherited;
13636
MarkReferencedDecls(Sema & S,SourceLocation Loc)13637 MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) { }
13638
13639 bool TraverseTemplateArgument(const TemplateArgument &Arg);
13640 bool TraverseRecordType(RecordType *T);
13641 };
13642 }
13643
TraverseTemplateArgument(const TemplateArgument & Arg)13644 bool MarkReferencedDecls::TraverseTemplateArgument(
13645 const TemplateArgument &Arg) {
13646 if (Arg.getKind() == TemplateArgument::Declaration) {
13647 if (Decl *D = Arg.getAsDecl())
13648 S.MarkAnyDeclReferenced(Loc, D, true);
13649 }
13650
13651 return Inherited::TraverseTemplateArgument(Arg);
13652 }
13653
TraverseRecordType(RecordType * T)13654 bool MarkReferencedDecls::TraverseRecordType(RecordType *T) {
13655 if (ClassTemplateSpecializationDecl *Spec
13656 = dyn_cast<ClassTemplateSpecializationDecl>(T->getDecl())) {
13657 const TemplateArgumentList &Args = Spec->getTemplateArgs();
13658 return TraverseTemplateArguments(Args.data(), Args.size());
13659 }
13660
13661 return true;
13662 }
13663
MarkDeclarationsReferencedInType(SourceLocation Loc,QualType T)13664 void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) {
13665 MarkReferencedDecls Marker(*this, Loc);
13666 Marker.TraverseType(Context.getCanonicalType(T));
13667 }
13668
13669 namespace {
13670 /// \brief Helper class that marks all of the declarations referenced by
13671 /// potentially-evaluated subexpressions as "referenced".
13672 class EvaluatedExprMarker : public EvaluatedExprVisitor<EvaluatedExprMarker> {
13673 Sema &S;
13674 bool SkipLocalVariables;
13675
13676 public:
13677 typedef EvaluatedExprVisitor<EvaluatedExprMarker> Inherited;
13678
EvaluatedExprMarker(Sema & S,bool SkipLocalVariables)13679 EvaluatedExprMarker(Sema &S, bool SkipLocalVariables)
13680 : Inherited(S.Context), S(S), SkipLocalVariables(SkipLocalVariables) { }
13681
VisitDeclRefExpr(DeclRefExpr * E)13682 void VisitDeclRefExpr(DeclRefExpr *E) {
13683 // If we were asked not to visit local variables, don't.
13684 if (SkipLocalVariables) {
13685 if (VarDecl *VD = dyn_cast<VarDecl>(E->getDecl()))
13686 if (VD->hasLocalStorage())
13687 return;
13688 }
13689
13690 S.MarkDeclRefReferenced(E);
13691 }
13692
VisitMemberExpr(MemberExpr * E)13693 void VisitMemberExpr(MemberExpr *E) {
13694 S.MarkMemberReferenced(E);
13695 Inherited::VisitMemberExpr(E);
13696 }
13697
VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr * E)13698 void VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) {
13699 S.MarkFunctionReferenced(E->getLocStart(),
13700 const_cast<CXXDestructorDecl*>(E->getTemporary()->getDestructor()));
13701 Visit(E->getSubExpr());
13702 }
13703
VisitCXXNewExpr(CXXNewExpr * E)13704 void VisitCXXNewExpr(CXXNewExpr *E) {
13705 if (E->getOperatorNew())
13706 S.MarkFunctionReferenced(E->getLocStart(), E->getOperatorNew());
13707 if (E->getOperatorDelete())
13708 S.MarkFunctionReferenced(E->getLocStart(), E->getOperatorDelete());
13709 Inherited::VisitCXXNewExpr(E);
13710 }
13711
VisitCXXDeleteExpr(CXXDeleteExpr * E)13712 void VisitCXXDeleteExpr(CXXDeleteExpr *E) {
13713 if (E->getOperatorDelete())
13714 S.MarkFunctionReferenced(E->getLocStart(), E->getOperatorDelete());
13715 QualType Destroyed = S.Context.getBaseElementType(E->getDestroyedType());
13716 if (const RecordType *DestroyedRec = Destroyed->getAs<RecordType>()) {
13717 CXXRecordDecl *Record = cast<CXXRecordDecl>(DestroyedRec->getDecl());
13718 S.MarkFunctionReferenced(E->getLocStart(),
13719 S.LookupDestructor(Record));
13720 }
13721
13722 Inherited::VisitCXXDeleteExpr(E);
13723 }
13724
VisitCXXConstructExpr(CXXConstructExpr * E)13725 void VisitCXXConstructExpr(CXXConstructExpr *E) {
13726 S.MarkFunctionReferenced(E->getLocStart(), E->getConstructor());
13727 Inherited::VisitCXXConstructExpr(E);
13728 }
13729
VisitCXXDefaultArgExpr(CXXDefaultArgExpr * E)13730 void VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) {
13731 Visit(E->getExpr());
13732 }
13733
VisitImplicitCastExpr(ImplicitCastExpr * E)13734 void VisitImplicitCastExpr(ImplicitCastExpr *E) {
13735 Inherited::VisitImplicitCastExpr(E);
13736
13737 if (E->getCastKind() == CK_LValueToRValue)
13738 S.UpdateMarkingForLValueToRValue(E->getSubExpr());
13739 }
13740 };
13741 }
13742
13743 /// \brief Mark any declarations that appear within this expression or any
13744 /// potentially-evaluated subexpressions as "referenced".
13745 ///
13746 /// \param SkipLocalVariables If true, don't mark local variables as
13747 /// 'referenced'.
MarkDeclarationsReferencedInExpr(Expr * E,bool SkipLocalVariables)13748 void Sema::MarkDeclarationsReferencedInExpr(Expr *E,
13749 bool SkipLocalVariables) {
13750 EvaluatedExprMarker(*this, SkipLocalVariables).Visit(E);
13751 }
13752
13753 /// \brief Emit a diagnostic that describes an effect on the run-time behavior
13754 /// of the program being compiled.
13755 ///
13756 /// This routine emits the given diagnostic when the code currently being
13757 /// type-checked is "potentially evaluated", meaning that there is a
13758 /// possibility that the code will actually be executable. Code in sizeof()
13759 /// expressions, code used only during overload resolution, etc., are not
13760 /// potentially evaluated. This routine will suppress such diagnostics or,
13761 /// in the absolutely nutty case of potentially potentially evaluated
13762 /// expressions (C++ typeid), queue the diagnostic to potentially emit it
13763 /// later.
13764 ///
13765 /// This routine should be used for all diagnostics that describe the run-time
13766 /// behavior of a program, such as passing a non-POD value through an ellipsis.
13767 /// Failure to do so will likely result in spurious diagnostics or failures
13768 /// during overload resolution or within sizeof/alignof/typeof/typeid.
DiagRuntimeBehavior(SourceLocation Loc,const Stmt * Statement,const PartialDiagnostic & PD)13769 bool Sema::DiagRuntimeBehavior(SourceLocation Loc, const Stmt *Statement,
13770 const PartialDiagnostic &PD) {
13771 switch (ExprEvalContexts.back().Context) {
13772 case Unevaluated:
13773 case UnevaluatedAbstract:
13774 // The argument will never be evaluated, so don't complain.
13775 break;
13776
13777 case ConstantEvaluated:
13778 // Relevant diagnostics should be produced by constant evaluation.
13779 break;
13780
13781 case PotentiallyEvaluated:
13782 case PotentiallyEvaluatedIfUsed:
13783 if (Statement && getCurFunctionOrMethodDecl()) {
13784 FunctionScopes.back()->PossiblyUnreachableDiags.
13785 push_back(sema::PossiblyUnreachableDiag(PD, Loc, Statement));
13786 }
13787 else
13788 Diag(Loc, PD);
13789
13790 return true;
13791 }
13792
13793 return false;
13794 }
13795
CheckCallReturnType(QualType ReturnType,SourceLocation Loc,CallExpr * CE,FunctionDecl * FD)13796 bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc,
13797 CallExpr *CE, FunctionDecl *FD) {
13798 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType())
13799 return false;
13800
13801 // If we're inside a decltype's expression, don't check for a valid return
13802 // type or construct temporaries until we know whether this is the last call.
13803 if (ExprEvalContexts.back().IsDecltype) {
13804 ExprEvalContexts.back().DelayedDecltypeCalls.push_back(CE);
13805 return false;
13806 }
13807
13808 class CallReturnIncompleteDiagnoser : public TypeDiagnoser {
13809 FunctionDecl *FD;
13810 CallExpr *CE;
13811
13812 public:
13813 CallReturnIncompleteDiagnoser(FunctionDecl *FD, CallExpr *CE)
13814 : FD(FD), CE(CE) { }
13815
13816 void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
13817 if (!FD) {
13818 S.Diag(Loc, diag::err_call_incomplete_return)
13819 << T << CE->getSourceRange();
13820 return;
13821 }
13822
13823 S.Diag(Loc, diag::err_call_function_incomplete_return)
13824 << CE->getSourceRange() << FD->getDeclName() << T;
13825 S.Diag(FD->getLocation(), diag::note_entity_declared_at)
13826 << FD->getDeclName();
13827 }
13828 } Diagnoser(FD, CE);
13829
13830 if (RequireCompleteType(Loc, ReturnType, Diagnoser))
13831 return true;
13832
13833 return false;
13834 }
13835
13836 // Diagnose the s/=/==/ and s/\|=/!=/ typos. Note that adding parentheses
13837 // will prevent this condition from triggering, which is what we want.
DiagnoseAssignmentAsCondition(Expr * E)13838 void Sema::DiagnoseAssignmentAsCondition(Expr *E) {
13839 SourceLocation Loc;
13840
13841 unsigned diagnostic = diag::warn_condition_is_assignment;
13842 bool IsOrAssign = false;
13843
13844 if (BinaryOperator *Op = dyn_cast<BinaryOperator>(E)) {
13845 if (Op->getOpcode() != BO_Assign && Op->getOpcode() != BO_OrAssign)
13846 return;
13847
13848 IsOrAssign = Op->getOpcode() == BO_OrAssign;
13849
13850 // Greylist some idioms by putting them into a warning subcategory.
13851 if (ObjCMessageExpr *ME
13852 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) {
13853 Selector Sel = ME->getSelector();
13854
13855 // self = [<foo> init...]
13856 if (isSelfExpr(Op->getLHS()) && ME->getMethodFamily() == OMF_init)
13857 diagnostic = diag::warn_condition_is_idiomatic_assignment;
13858
13859 // <foo> = [<bar> nextObject]
13860 else if (Sel.isUnarySelector() && Sel.getNameForSlot(0) == "nextObject")
13861 diagnostic = diag::warn_condition_is_idiomatic_assignment;
13862 }
13863
13864 Loc = Op->getOperatorLoc();
13865 } else if (CXXOperatorCallExpr *Op = dyn_cast<CXXOperatorCallExpr>(E)) {
13866 if (Op->getOperator() != OO_Equal && Op->getOperator() != OO_PipeEqual)
13867 return;
13868
13869 IsOrAssign = Op->getOperator() == OO_PipeEqual;
13870 Loc = Op->getOperatorLoc();
13871 } else if (PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(E))
13872 return DiagnoseAssignmentAsCondition(POE->getSyntacticForm());
13873 else {
13874 // Not an assignment.
13875 return;
13876 }
13877
13878 Diag(Loc, diagnostic) << E->getSourceRange();
13879
13880 SourceLocation Open = E->getLocStart();
13881 SourceLocation Close = getLocForEndOfToken(E->getSourceRange().getEnd());
13882 Diag(Loc, diag::note_condition_assign_silence)
13883 << FixItHint::CreateInsertion(Open, "(")
13884 << FixItHint::CreateInsertion(Close, ")");
13885
13886 if (IsOrAssign)
13887 Diag(Loc, diag::note_condition_or_assign_to_comparison)
13888 << FixItHint::CreateReplacement(Loc, "!=");
13889 else
13890 Diag(Loc, diag::note_condition_assign_to_comparison)
13891 << FixItHint::CreateReplacement(Loc, "==");
13892 }
13893
13894 /// \brief Redundant parentheses over an equality comparison can indicate
13895 /// that the user intended an assignment used as condition.
DiagnoseEqualityWithExtraParens(ParenExpr * ParenE)13896 void Sema::DiagnoseEqualityWithExtraParens(ParenExpr *ParenE) {
13897 // Don't warn if the parens came from a macro.
13898 SourceLocation parenLoc = ParenE->getLocStart();
13899 if (parenLoc.isInvalid() || parenLoc.isMacroID())
13900 return;
13901 // Don't warn for dependent expressions.
13902 if (ParenE->isTypeDependent())
13903 return;
13904
13905 Expr *E = ParenE->IgnoreParens();
13906
13907 if (BinaryOperator *opE = dyn_cast<BinaryOperator>(E))
13908 if (opE->getOpcode() == BO_EQ &&
13909 opE->getLHS()->IgnoreParenImpCasts()->isModifiableLvalue(Context)
13910 == Expr::MLV_Valid) {
13911 SourceLocation Loc = opE->getOperatorLoc();
13912
13913 Diag(Loc, diag::warn_equality_with_extra_parens) << E->getSourceRange();
13914 SourceRange ParenERange = ParenE->getSourceRange();
13915 Diag(Loc, diag::note_equality_comparison_silence)
13916 << FixItHint::CreateRemoval(ParenERange.getBegin())
13917 << FixItHint::CreateRemoval(ParenERange.getEnd());
13918 Diag(Loc, diag::note_equality_comparison_to_assign)
13919 << FixItHint::CreateReplacement(Loc, "=");
13920 }
13921 }
13922
CheckBooleanCondition(Expr * E,SourceLocation Loc)13923 ExprResult Sema::CheckBooleanCondition(Expr *E, SourceLocation Loc) {
13924 DiagnoseAssignmentAsCondition(E);
13925 if (ParenExpr *parenE = dyn_cast<ParenExpr>(E))
13926 DiagnoseEqualityWithExtraParens(parenE);
13927
13928 ExprResult result = CheckPlaceholderExpr(E);
13929 if (result.isInvalid()) return ExprError();
13930 E = result.get();
13931
13932 if (!E->isTypeDependent()) {
13933 if (getLangOpts().CPlusPlus)
13934 return CheckCXXBooleanCondition(E); // C++ 6.4p4
13935
13936 ExprResult ERes = DefaultFunctionArrayLvalueConversion(E);
13937 if (ERes.isInvalid())
13938 return ExprError();
13939 E = ERes.get();
13940
13941 QualType T = E->getType();
13942 if (!T->isScalarType()) { // C99 6.8.4.1p1
13943 Diag(Loc, diag::err_typecheck_statement_requires_scalar)
13944 << T << E->getSourceRange();
13945 return ExprError();
13946 }
13947 CheckBoolLikeConversion(E, Loc);
13948 }
13949
13950 return E;
13951 }
13952
ActOnBooleanCondition(Scope * S,SourceLocation Loc,Expr * SubExpr)13953 ExprResult Sema::ActOnBooleanCondition(Scope *S, SourceLocation Loc,
13954 Expr *SubExpr) {
13955 if (!SubExpr)
13956 return ExprError();
13957
13958 return CheckBooleanCondition(SubExpr, Loc);
13959 }
13960
13961 namespace {
13962 /// A visitor for rebuilding a call to an __unknown_any expression
13963 /// to have an appropriate type.
13964 struct RebuildUnknownAnyFunction
13965 : StmtVisitor<RebuildUnknownAnyFunction, ExprResult> {
13966
13967 Sema &S;
13968
RebuildUnknownAnyFunction__anon76e074960b11::RebuildUnknownAnyFunction13969 RebuildUnknownAnyFunction(Sema &S) : S(S) {}
13970
VisitStmt__anon76e074960b11::RebuildUnknownAnyFunction13971 ExprResult VisitStmt(Stmt *S) {
13972 llvm_unreachable("unexpected statement!");
13973 }
13974
VisitExpr__anon76e074960b11::RebuildUnknownAnyFunction13975 ExprResult VisitExpr(Expr *E) {
13976 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_call)
13977 << E->getSourceRange();
13978 return ExprError();
13979 }
13980
13981 /// Rebuild an expression which simply semantically wraps another
13982 /// expression which it shares the type and value kind of.
rebuildSugarExpr__anon76e074960b11::RebuildUnknownAnyFunction13983 template <class T> ExprResult rebuildSugarExpr(T *E) {
13984 ExprResult SubResult = Visit(E->getSubExpr());
13985 if (SubResult.isInvalid()) return ExprError();
13986
13987 Expr *SubExpr = SubResult.get();
13988 E->setSubExpr(SubExpr);
13989 E->setType(SubExpr->getType());
13990 E->setValueKind(SubExpr->getValueKind());
13991 assert(E->getObjectKind() == OK_Ordinary);
13992 return E;
13993 }
13994
VisitParenExpr__anon76e074960b11::RebuildUnknownAnyFunction13995 ExprResult VisitParenExpr(ParenExpr *E) {
13996 return rebuildSugarExpr(E);
13997 }
13998
VisitUnaryExtension__anon76e074960b11::RebuildUnknownAnyFunction13999 ExprResult VisitUnaryExtension(UnaryOperator *E) {
14000 return rebuildSugarExpr(E);
14001 }
14002
VisitUnaryAddrOf__anon76e074960b11::RebuildUnknownAnyFunction14003 ExprResult VisitUnaryAddrOf(UnaryOperator *E) {
14004 ExprResult SubResult = Visit(E->getSubExpr());
14005 if (SubResult.isInvalid()) return ExprError();
14006
14007 Expr *SubExpr = SubResult.get();
14008 E->setSubExpr(SubExpr);
14009 E->setType(S.Context.getPointerType(SubExpr->getType()));
14010 assert(E->getValueKind() == VK_RValue);
14011 assert(E->getObjectKind() == OK_Ordinary);
14012 return E;
14013 }
14014
resolveDecl__anon76e074960b11::RebuildUnknownAnyFunction14015 ExprResult resolveDecl(Expr *E, ValueDecl *VD) {
14016 if (!isa<FunctionDecl>(VD)) return VisitExpr(E);
14017
14018 E->setType(VD->getType());
14019
14020 assert(E->getValueKind() == VK_RValue);
14021 if (S.getLangOpts().CPlusPlus &&
14022 !(isa<CXXMethodDecl>(VD) &&
14023 cast<CXXMethodDecl>(VD)->isInstance()))
14024 E->setValueKind(VK_LValue);
14025
14026 return E;
14027 }
14028
VisitMemberExpr__anon76e074960b11::RebuildUnknownAnyFunction14029 ExprResult VisitMemberExpr(MemberExpr *E) {
14030 return resolveDecl(E, E->getMemberDecl());
14031 }
14032
VisitDeclRefExpr__anon76e074960b11::RebuildUnknownAnyFunction14033 ExprResult VisitDeclRefExpr(DeclRefExpr *E) {
14034 return resolveDecl(E, E->getDecl());
14035 }
14036 };
14037 }
14038
14039 /// Given a function expression of unknown-any type, try to rebuild it
14040 /// to have a function type.
rebuildUnknownAnyFunction(Sema & S,Expr * FunctionExpr)14041 static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *FunctionExpr) {
14042 ExprResult Result = RebuildUnknownAnyFunction(S).Visit(FunctionExpr);
14043 if (Result.isInvalid()) return ExprError();
14044 return S.DefaultFunctionArrayConversion(Result.get());
14045 }
14046
14047 namespace {
14048 /// A visitor for rebuilding an expression of type __unknown_anytype
14049 /// into one which resolves the type directly on the referring
14050 /// expression. Strict preservation of the original source
14051 /// structure is not a goal.
14052 struct RebuildUnknownAnyExpr
14053 : StmtVisitor<RebuildUnknownAnyExpr, ExprResult> {
14054
14055 Sema &S;
14056
14057 /// The current destination type.
14058 QualType DestType;
14059
RebuildUnknownAnyExpr__anon76e074960c11::RebuildUnknownAnyExpr14060 RebuildUnknownAnyExpr(Sema &S, QualType CastType)
14061 : S(S), DestType(CastType) {}
14062
VisitStmt__anon76e074960c11::RebuildUnknownAnyExpr14063 ExprResult VisitStmt(Stmt *S) {
14064 llvm_unreachable("unexpected statement!");
14065 }
14066
VisitExpr__anon76e074960c11::RebuildUnknownAnyExpr14067 ExprResult VisitExpr(Expr *E) {
14068 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_expr)
14069 << E->getSourceRange();
14070 return ExprError();
14071 }
14072
14073 ExprResult VisitCallExpr(CallExpr *E);
14074 ExprResult VisitObjCMessageExpr(ObjCMessageExpr *E);
14075
14076 /// Rebuild an expression which simply semantically wraps another
14077 /// expression which it shares the type and value kind of.
rebuildSugarExpr__anon76e074960c11::RebuildUnknownAnyExpr14078 template <class T> ExprResult rebuildSugarExpr(T *E) {
14079 ExprResult SubResult = Visit(E->getSubExpr());
14080 if (SubResult.isInvalid()) return ExprError();
14081 Expr *SubExpr = SubResult.get();
14082 E->setSubExpr(SubExpr);
14083 E->setType(SubExpr->getType());
14084 E->setValueKind(SubExpr->getValueKind());
14085 assert(E->getObjectKind() == OK_Ordinary);
14086 return E;
14087 }
14088
VisitParenExpr__anon76e074960c11::RebuildUnknownAnyExpr14089 ExprResult VisitParenExpr(ParenExpr *E) {
14090 return rebuildSugarExpr(E);
14091 }
14092
VisitUnaryExtension__anon76e074960c11::RebuildUnknownAnyExpr14093 ExprResult VisitUnaryExtension(UnaryOperator *E) {
14094 return rebuildSugarExpr(E);
14095 }
14096
VisitUnaryAddrOf__anon76e074960c11::RebuildUnknownAnyExpr14097 ExprResult VisitUnaryAddrOf(UnaryOperator *E) {
14098 const PointerType *Ptr = DestType->getAs<PointerType>();
14099 if (!Ptr) {
14100 S.Diag(E->getOperatorLoc(), diag::err_unknown_any_addrof)
14101 << E->getSourceRange();
14102 return ExprError();
14103 }
14104 assert(E->getValueKind() == VK_RValue);
14105 assert(E->getObjectKind() == OK_Ordinary);
14106 E->setType(DestType);
14107
14108 // Build the sub-expression as if it were an object of the pointee type.
14109 DestType = Ptr->getPointeeType();
14110 ExprResult SubResult = Visit(E->getSubExpr());
14111 if (SubResult.isInvalid()) return ExprError();
14112 E->setSubExpr(SubResult.get());
14113 return E;
14114 }
14115
14116 ExprResult VisitImplicitCastExpr(ImplicitCastExpr *E);
14117
14118 ExprResult resolveDecl(Expr *E, ValueDecl *VD);
14119
VisitMemberExpr__anon76e074960c11::RebuildUnknownAnyExpr14120 ExprResult VisitMemberExpr(MemberExpr *E) {
14121 return resolveDecl(E, E->getMemberDecl());
14122 }
14123
VisitDeclRefExpr__anon76e074960c11::RebuildUnknownAnyExpr14124 ExprResult VisitDeclRefExpr(DeclRefExpr *E) {
14125 return resolveDecl(E, E->getDecl());
14126 }
14127 };
14128 }
14129
14130 /// Rebuilds a call expression which yielded __unknown_anytype.
VisitCallExpr(CallExpr * E)14131 ExprResult RebuildUnknownAnyExpr::VisitCallExpr(CallExpr *E) {
14132 Expr *CalleeExpr = E->getCallee();
14133
14134 enum FnKind {
14135 FK_MemberFunction,
14136 FK_FunctionPointer,
14137 FK_BlockPointer
14138 };
14139
14140 FnKind Kind;
14141 QualType CalleeType = CalleeExpr->getType();
14142 if (CalleeType == S.Context.BoundMemberTy) {
14143 assert(isa<CXXMemberCallExpr>(E) || isa<CXXOperatorCallExpr>(E));
14144 Kind = FK_MemberFunction;
14145 CalleeType = Expr::findBoundMemberType(CalleeExpr);
14146 } else if (const PointerType *Ptr = CalleeType->getAs<PointerType>()) {
14147 CalleeType = Ptr->getPointeeType();
14148 Kind = FK_FunctionPointer;
14149 } else {
14150 CalleeType = CalleeType->castAs<BlockPointerType>()->getPointeeType();
14151 Kind = FK_BlockPointer;
14152 }
14153 const FunctionType *FnType = CalleeType->castAs<FunctionType>();
14154
14155 // Verify that this is a legal result type of a function.
14156 if (DestType->isArrayType() || DestType->isFunctionType()) {
14157 unsigned diagID = diag::err_func_returning_array_function;
14158 if (Kind == FK_BlockPointer)
14159 diagID = diag::err_block_returning_array_function;
14160
14161 S.Diag(E->getExprLoc(), diagID)
14162 << DestType->isFunctionType() << DestType;
14163 return ExprError();
14164 }
14165
14166 // Otherwise, go ahead and set DestType as the call's result.
14167 E->setType(DestType.getNonLValueExprType(S.Context));
14168 E->setValueKind(Expr::getValueKindForType(DestType));
14169 assert(E->getObjectKind() == OK_Ordinary);
14170
14171 // Rebuild the function type, replacing the result type with DestType.
14172 const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FnType);
14173 if (Proto) {
14174 // __unknown_anytype(...) is a special case used by the debugger when
14175 // it has no idea what a function's signature is.
14176 //
14177 // We want to build this call essentially under the K&R
14178 // unprototyped rules, but making a FunctionNoProtoType in C++
14179 // would foul up all sorts of assumptions. However, we cannot
14180 // simply pass all arguments as variadic arguments, nor can we
14181 // portably just call the function under a non-variadic type; see
14182 // the comment on IR-gen's TargetInfo::isNoProtoCallVariadic.
14183 // However, it turns out that in practice it is generally safe to
14184 // call a function declared as "A foo(B,C,D);" under the prototype
14185 // "A foo(B,C,D,...);". The only known exception is with the
14186 // Windows ABI, where any variadic function is implicitly cdecl
14187 // regardless of its normal CC. Therefore we change the parameter
14188 // types to match the types of the arguments.
14189 //
14190 // This is a hack, but it is far superior to moving the
14191 // corresponding target-specific code from IR-gen to Sema/AST.
14192
14193 ArrayRef<QualType> ParamTypes = Proto->getParamTypes();
14194 SmallVector<QualType, 8> ArgTypes;
14195 if (ParamTypes.empty() && Proto->isVariadic()) { // the special case
14196 ArgTypes.reserve(E->getNumArgs());
14197 for (unsigned i = 0, e = E->getNumArgs(); i != e; ++i) {
14198 Expr *Arg = E->getArg(i);
14199 QualType ArgType = Arg->getType();
14200 if (E->isLValue()) {
14201 ArgType = S.Context.getLValueReferenceType(ArgType);
14202 } else if (E->isXValue()) {
14203 ArgType = S.Context.getRValueReferenceType(ArgType);
14204 }
14205 ArgTypes.push_back(ArgType);
14206 }
14207 ParamTypes = ArgTypes;
14208 }
14209 DestType = S.Context.getFunctionType(DestType, ParamTypes,
14210 Proto->getExtProtoInfo());
14211 } else {
14212 DestType = S.Context.getFunctionNoProtoType(DestType,
14213 FnType->getExtInfo());
14214 }
14215
14216 // Rebuild the appropriate pointer-to-function type.
14217 switch (Kind) {
14218 case FK_MemberFunction:
14219 // Nothing to do.
14220 break;
14221
14222 case FK_FunctionPointer:
14223 DestType = S.Context.getPointerType(DestType);
14224 break;
14225
14226 case FK_BlockPointer:
14227 DestType = S.Context.getBlockPointerType(DestType);
14228 break;
14229 }
14230
14231 // Finally, we can recurse.
14232 ExprResult CalleeResult = Visit(CalleeExpr);
14233 if (!CalleeResult.isUsable()) return ExprError();
14234 E->setCallee(CalleeResult.get());
14235
14236 // Bind a temporary if necessary.
14237 return S.MaybeBindToTemporary(E);
14238 }
14239
VisitObjCMessageExpr(ObjCMessageExpr * E)14240 ExprResult RebuildUnknownAnyExpr::VisitObjCMessageExpr(ObjCMessageExpr *E) {
14241 // Verify that this is a legal result type of a call.
14242 if (DestType->isArrayType() || DestType->isFunctionType()) {
14243 S.Diag(E->getExprLoc(), diag::err_func_returning_array_function)
14244 << DestType->isFunctionType() << DestType;
14245 return ExprError();
14246 }
14247
14248 // Rewrite the method result type if available.
14249 if (ObjCMethodDecl *Method = E->getMethodDecl()) {
14250 assert(Method->getReturnType() == S.Context.UnknownAnyTy);
14251 Method->setReturnType(DestType);
14252 }
14253
14254 // Change the type of the message.
14255 E->setType(DestType.getNonReferenceType());
14256 E->setValueKind(Expr::getValueKindForType(DestType));
14257
14258 return S.MaybeBindToTemporary(E);
14259 }
14260
VisitImplicitCastExpr(ImplicitCastExpr * E)14261 ExprResult RebuildUnknownAnyExpr::VisitImplicitCastExpr(ImplicitCastExpr *E) {
14262 // The only case we should ever see here is a function-to-pointer decay.
14263 if (E->getCastKind() == CK_FunctionToPointerDecay) {
14264 assert(E->getValueKind() == VK_RValue);
14265 assert(E->getObjectKind() == OK_Ordinary);
14266
14267 E->setType(DestType);
14268
14269 // Rebuild the sub-expression as the pointee (function) type.
14270 DestType = DestType->castAs<PointerType>()->getPointeeType();
14271
14272 ExprResult Result = Visit(E->getSubExpr());
14273 if (!Result.isUsable()) return ExprError();
14274
14275 E->setSubExpr(Result.get());
14276 return E;
14277 } else if (E->getCastKind() == CK_LValueToRValue) {
14278 assert(E->getValueKind() == VK_RValue);
14279 assert(E->getObjectKind() == OK_Ordinary);
14280
14281 assert(isa<BlockPointerType>(E->getType()));
14282
14283 E->setType(DestType);
14284
14285 // The sub-expression has to be a lvalue reference, so rebuild it as such.
14286 DestType = S.Context.getLValueReferenceType(DestType);
14287
14288 ExprResult Result = Visit(E->getSubExpr());
14289 if (!Result.isUsable()) return ExprError();
14290
14291 E->setSubExpr(Result.get());
14292 return E;
14293 } else {
14294 llvm_unreachable("Unhandled cast type!");
14295 }
14296 }
14297
resolveDecl(Expr * E,ValueDecl * VD)14298 ExprResult RebuildUnknownAnyExpr::resolveDecl(Expr *E, ValueDecl *VD) {
14299 ExprValueKind ValueKind = VK_LValue;
14300 QualType Type = DestType;
14301
14302 // We know how to make this work for certain kinds of decls:
14303
14304 // - functions
14305 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(VD)) {
14306 if (const PointerType *Ptr = Type->getAs<PointerType>()) {
14307 DestType = Ptr->getPointeeType();
14308 ExprResult Result = resolveDecl(E, VD);
14309 if (Result.isInvalid()) return ExprError();
14310 return S.ImpCastExprToType(Result.get(), Type,
14311 CK_FunctionToPointerDecay, VK_RValue);
14312 }
14313
14314 if (!Type->isFunctionType()) {
14315 S.Diag(E->getExprLoc(), diag::err_unknown_any_function)
14316 << VD << E->getSourceRange();
14317 return ExprError();
14318 }
14319 if (const FunctionProtoType *FT = Type->getAs<FunctionProtoType>()) {
14320 // We must match the FunctionDecl's type to the hack introduced in
14321 // RebuildUnknownAnyExpr::VisitCallExpr to vararg functions of unknown
14322 // type. See the lengthy commentary in that routine.
14323 QualType FDT = FD->getType();
14324 const FunctionType *FnType = FDT->castAs<FunctionType>();
14325 const FunctionProtoType *Proto = dyn_cast_or_null<FunctionProtoType>(FnType);
14326 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E);
14327 if (DRE && Proto && Proto->getParamTypes().empty() && Proto->isVariadic()) {
14328 SourceLocation Loc = FD->getLocation();
14329 FunctionDecl *NewFD = FunctionDecl::Create(FD->getASTContext(),
14330 FD->getDeclContext(),
14331 Loc, Loc, FD->getNameInfo().getName(),
14332 DestType, FD->getTypeSourceInfo(),
14333 SC_None, false/*isInlineSpecified*/,
14334 FD->hasPrototype(),
14335 false/*isConstexprSpecified*/);
14336
14337 if (FD->getQualifier())
14338 NewFD->setQualifierInfo(FD->getQualifierLoc());
14339
14340 SmallVector<ParmVarDecl*, 16> Params;
14341 for (const auto &AI : FT->param_types()) {
14342 ParmVarDecl *Param =
14343 S.BuildParmVarDeclForTypedef(FD, Loc, AI);
14344 Param->setScopeInfo(0, Params.size());
14345 Params.push_back(Param);
14346 }
14347 NewFD->setParams(Params);
14348 DRE->setDecl(NewFD);
14349 VD = DRE->getDecl();
14350 }
14351 }
14352
14353 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD))
14354 if (MD->isInstance()) {
14355 ValueKind = VK_RValue;
14356 Type = S.Context.BoundMemberTy;
14357 }
14358
14359 // Function references aren't l-values in C.
14360 if (!S.getLangOpts().CPlusPlus)
14361 ValueKind = VK_RValue;
14362
14363 // - variables
14364 } else if (isa<VarDecl>(VD)) {
14365 if (const ReferenceType *RefTy = Type->getAs<ReferenceType>()) {
14366 Type = RefTy->getPointeeType();
14367 } else if (Type->isFunctionType()) {
14368 S.Diag(E->getExprLoc(), diag::err_unknown_any_var_function_type)
14369 << VD << E->getSourceRange();
14370 return ExprError();
14371 }
14372
14373 // - nothing else
14374 } else {
14375 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_decl)
14376 << VD << E->getSourceRange();
14377 return ExprError();
14378 }
14379
14380 // Modifying the declaration like this is friendly to IR-gen but
14381 // also really dangerous.
14382 VD->setType(DestType);
14383 E->setType(Type);
14384 E->setValueKind(ValueKind);
14385 return E;
14386 }
14387
14388 /// Check a cast of an unknown-any type. We intentionally only
14389 /// trigger this for C-style casts.
checkUnknownAnyCast(SourceRange TypeRange,QualType CastType,Expr * CastExpr,CastKind & CastKind,ExprValueKind & VK,CXXCastPath & Path)14390 ExprResult Sema::checkUnknownAnyCast(SourceRange TypeRange, QualType CastType,
14391 Expr *CastExpr, CastKind &CastKind,
14392 ExprValueKind &VK, CXXCastPath &Path) {
14393 // Rewrite the casted expression from scratch.
14394 ExprResult result = RebuildUnknownAnyExpr(*this, CastType).Visit(CastExpr);
14395 if (!result.isUsable()) return ExprError();
14396
14397 CastExpr = result.get();
14398 VK = CastExpr->getValueKind();
14399 CastKind = CK_NoOp;
14400
14401 return CastExpr;
14402 }
14403
forceUnknownAnyToType(Expr * E,QualType ToType)14404 ExprResult Sema::forceUnknownAnyToType(Expr *E, QualType ToType) {
14405 return RebuildUnknownAnyExpr(*this, ToType).Visit(E);
14406 }
14407
checkUnknownAnyArg(SourceLocation callLoc,Expr * arg,QualType & paramType)14408 ExprResult Sema::checkUnknownAnyArg(SourceLocation callLoc,
14409 Expr *arg, QualType ¶mType) {
14410 // If the syntactic form of the argument is not an explicit cast of
14411 // any sort, just do default argument promotion.
14412 ExplicitCastExpr *castArg = dyn_cast<ExplicitCastExpr>(arg->IgnoreParens());
14413 if (!castArg) {
14414 ExprResult result = DefaultArgumentPromotion(arg);
14415 if (result.isInvalid()) return ExprError();
14416 paramType = result.get()->getType();
14417 return result;
14418 }
14419
14420 // Otherwise, use the type that was written in the explicit cast.
14421 assert(!arg->hasPlaceholderType());
14422 paramType = castArg->getTypeAsWritten();
14423
14424 // Copy-initialize a parameter of that type.
14425 InitializedEntity entity =
14426 InitializedEntity::InitializeParameter(Context, paramType,
14427 /*consumed*/ false);
14428 return PerformCopyInitialization(entity, callLoc, arg);
14429 }
14430
diagnoseUnknownAnyExpr(Sema & S,Expr * E)14431 static ExprResult diagnoseUnknownAnyExpr(Sema &S, Expr *E) {
14432 Expr *orig = E;
14433 unsigned diagID = diag::err_uncasted_use_of_unknown_any;
14434 while (true) {
14435 E = E->IgnoreParenImpCasts();
14436 if (CallExpr *call = dyn_cast<CallExpr>(E)) {
14437 E = call->getCallee();
14438 diagID = diag::err_uncasted_call_of_unknown_any;
14439 } else {
14440 break;
14441 }
14442 }
14443
14444 SourceLocation loc;
14445 NamedDecl *d;
14446 if (DeclRefExpr *ref = dyn_cast<DeclRefExpr>(E)) {
14447 loc = ref->getLocation();
14448 d = ref->getDecl();
14449 } else if (MemberExpr *mem = dyn_cast<MemberExpr>(E)) {
14450 loc = mem->getMemberLoc();
14451 d = mem->getMemberDecl();
14452 } else if (ObjCMessageExpr *msg = dyn_cast<ObjCMessageExpr>(E)) {
14453 diagID = diag::err_uncasted_call_of_unknown_any;
14454 loc = msg->getSelectorStartLoc();
14455 d = msg->getMethodDecl();
14456 if (!d) {
14457 S.Diag(loc, diag::err_uncasted_send_to_unknown_any_method)
14458 << static_cast<unsigned>(msg->isClassMessage()) << msg->getSelector()
14459 << orig->getSourceRange();
14460 return ExprError();
14461 }
14462 } else {
14463 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_expr)
14464 << E->getSourceRange();
14465 return ExprError();
14466 }
14467
14468 S.Diag(loc, diagID) << d << orig->getSourceRange();
14469
14470 // Never recoverable.
14471 return ExprError();
14472 }
14473
14474 /// Check for operands with placeholder types and complain if found.
14475 /// Returns true if there was an error and no recovery was possible.
CheckPlaceholderExpr(Expr * E)14476 ExprResult Sema::CheckPlaceholderExpr(Expr *E) {
14477 if (!getLangOpts().CPlusPlus) {
14478 // C cannot handle TypoExpr nodes on either side of a binop because it
14479 // doesn't handle dependent types properly, so make sure any TypoExprs have
14480 // been dealt with before checking the operands.
14481 ExprResult Result = CorrectDelayedTyposInExpr(E);
14482 if (!Result.isUsable()) return ExprError();
14483 E = Result.get();
14484 }
14485
14486 const BuiltinType *placeholderType = E->getType()->getAsPlaceholderType();
14487 if (!placeholderType) return E;
14488
14489 switch (placeholderType->getKind()) {
14490
14491 // Overloaded expressions.
14492 case BuiltinType::Overload: {
14493 // Try to resolve a single function template specialization.
14494 // This is obligatory.
14495 ExprResult result = E;
14496 if (ResolveAndFixSingleFunctionTemplateSpecialization(result, false)) {
14497 return result;
14498
14499 // If that failed, try to recover with a call.
14500 } else {
14501 tryToRecoverWithCall(result, PDiag(diag::err_ovl_unresolvable),
14502 /*complain*/ true);
14503 return result;
14504 }
14505 }
14506
14507 // Bound member functions.
14508 case BuiltinType::BoundMember: {
14509 ExprResult result = E;
14510 const Expr *BME = E->IgnoreParens();
14511 PartialDiagnostic PD = PDiag(diag::err_bound_member_function);
14512 // Try to give a nicer diagnostic if it is a bound member that we recognize.
14513 if (isa<CXXPseudoDestructorExpr>(BME)) {
14514 PD = PDiag(diag::err_dtor_expr_without_call) << /*pseudo-destructor*/ 1;
14515 } else if (const auto *ME = dyn_cast<MemberExpr>(BME)) {
14516 if (ME->getMemberNameInfo().getName().getNameKind() ==
14517 DeclarationName::CXXDestructorName)
14518 PD = PDiag(diag::err_dtor_expr_without_call) << /*destructor*/ 0;
14519 }
14520 tryToRecoverWithCall(result, PD,
14521 /*complain*/ true);
14522 return result;
14523 }
14524
14525 // ARC unbridged casts.
14526 case BuiltinType::ARCUnbridgedCast: {
14527 Expr *realCast = stripARCUnbridgedCast(E);
14528 diagnoseARCUnbridgedCast(realCast);
14529 return realCast;
14530 }
14531
14532 // Expressions of unknown type.
14533 case BuiltinType::UnknownAny:
14534 return diagnoseUnknownAnyExpr(*this, E);
14535
14536 // Pseudo-objects.
14537 case BuiltinType::PseudoObject:
14538 return checkPseudoObjectRValue(E);
14539
14540 case BuiltinType::BuiltinFn: {
14541 // Accept __noop without parens by implicitly converting it to a call expr.
14542 auto *DRE = dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts());
14543 if (DRE) {
14544 auto *FD = cast<FunctionDecl>(DRE->getDecl());
14545 if (FD->getBuiltinID() == Builtin::BI__noop) {
14546 E = ImpCastExprToType(E, Context.getPointerType(FD->getType()),
14547 CK_BuiltinFnToFnPtr).get();
14548 return new (Context) CallExpr(Context, E, None, Context.IntTy,
14549 VK_RValue, SourceLocation());
14550 }
14551 }
14552
14553 Diag(E->getLocStart(), diag::err_builtin_fn_use);
14554 return ExprError();
14555 }
14556
14557 // Expressions of unknown type.
14558 case BuiltinType::OMPArraySection:
14559 Diag(E->getLocStart(), diag::err_omp_array_section_use);
14560 return ExprError();
14561
14562 // Everything else should be impossible.
14563 #define BUILTIN_TYPE(Id, SingletonId) \
14564 case BuiltinType::Id:
14565 #define PLACEHOLDER_TYPE(Id, SingletonId)
14566 #include "clang/AST/BuiltinTypes.def"
14567 break;
14568 }
14569
14570 llvm_unreachable("invalid placeholder type!");
14571 }
14572
CheckCaseExpression(Expr * E)14573 bool Sema::CheckCaseExpression(Expr *E) {
14574 if (E->isTypeDependent())
14575 return true;
14576 if (E->isValueDependent() || E->isIntegerConstantExpr(Context))
14577 return E->getType()->isIntegralOrEnumerationType();
14578 return false;
14579 }
14580
14581 /// ActOnObjCBoolLiteral - Parse {__objc_yes,__objc_no} literals.
14582 ExprResult
ActOnObjCBoolLiteral(SourceLocation OpLoc,tok::TokenKind Kind)14583 Sema::ActOnObjCBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) {
14584 assert((Kind == tok::kw___objc_yes || Kind == tok::kw___objc_no) &&
14585 "Unknown Objective-C Boolean value!");
14586 QualType BoolT = Context.ObjCBuiltinBoolTy;
14587 if (!Context.getBOOLDecl()) {
14588 LookupResult Result(*this, &Context.Idents.get("BOOL"), OpLoc,
14589 Sema::LookupOrdinaryName);
14590 if (LookupName(Result, getCurScope()) && Result.isSingleResult()) {
14591 NamedDecl *ND = Result.getFoundDecl();
14592 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(ND))
14593 Context.setBOOLDecl(TD);
14594 }
14595 }
14596 if (Context.getBOOLDecl())
14597 BoolT = Context.getBOOLType();
14598 return new (Context)
14599 ObjCBoolLiteralExpr(Kind == tok::kw___objc_yes, BoolT, OpLoc);
14600 }
14601