1 //===--- DiagnosticIDs.h - Diagnostic IDs Handling --------------*- C++ -*-===//
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 /// \file
11 /// \brief Defines the Diagnostic IDs-related interfaces.
12 ///
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_CLANG_BASIC_DIAGNOSTICIDS_H
16 #define LLVM_CLANG_BASIC_DIAGNOSTICIDS_H
17 
18 #include "clang/Basic/LLVM.h"
19 #include "llvm/ADT/IntrusiveRefCntPtr.h"
20 #include "llvm/ADT/StringRef.h"
21 
22 namespace clang {
23   class DiagnosticsEngine;
24   class SourceLocation;
25 
26   // Import the diagnostic enums themselves.
27   namespace diag {
28     // Start position for diagnostics.
29     enum {
30       DIAG_START_COMMON        =                                 0,
31       DIAG_START_DRIVER        = DIAG_START_COMMON          +  300,
32       DIAG_START_FRONTEND      = DIAG_START_DRIVER          +  100,
33       DIAG_START_SERIALIZATION = DIAG_START_FRONTEND        +  100,
34       DIAG_START_LEX           = DIAG_START_SERIALIZATION   +  120,
35       DIAG_START_PARSE         = DIAG_START_LEX             +  300,
36       DIAG_START_AST           = DIAG_START_PARSE           +  500,
37       DIAG_START_COMMENT       = DIAG_START_AST             +  110,
38       DIAG_START_SEMA          = DIAG_START_COMMENT         +  100,
39       DIAG_START_ANALYSIS      = DIAG_START_SEMA            + 3000,
40       DIAG_UPPER_LIMIT         = DIAG_START_ANALYSIS        +  100
41     };
42 
43     class CustomDiagInfo;
44 
45     /// \brief All of the diagnostics that can be emitted by the frontend.
46     typedef unsigned kind;
47 
48     // Get typedefs for common diagnostics.
49     enum {
50 #define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,\
51              SFINAE,CATEGORY,NOWERROR,SHOWINSYSHEADER) ENUM,
52 #define COMMONSTART
53 #include "clang/Basic/DiagnosticCommonKinds.inc"
54       NUM_BUILTIN_COMMON_DIAGNOSTICS
55 #undef DIAG
56     };
57 
58     /// Enum values that allow the client to map NOTEs, WARNINGs, and EXTENSIONs
59     /// to either Ignore (nothing), Remark (emit a remark), Warning
60     /// (emit a warning) or Error (emit as an error).  It allows clients to
61     /// map ERRORs to Error or Fatal (stop emitting diagnostics after this one).
62     enum class Severity {
63       // NOTE: 0 means "uncomputed".
64       Ignored = 1, ///< Do not present this diagnostic, ignore it.
65       Remark = 2,  ///< Present this diagnostic as a remark.
66       Warning = 3, ///< Present this diagnostic as a warning.
67       Error = 4,   ///< Present this diagnostic as an error.
68       Fatal = 5    ///< Present this diagnostic as a fatal error.
69     };
70 
71     /// Flavors of diagnostics we can emit. Used to filter for a particular
72     /// kind of diagnostic (for instance, for -W/-R flags).
73     enum class Flavor {
74       WarningOrError, ///< A diagnostic that indicates a problem or potential
75                       ///< problem. Can be made fatal by -Werror.
76       Remark          ///< A diagnostic that indicates normal progress through
77                       ///< compilation.
78     };
79   }
80 
81 class DiagnosticMapping {
82   unsigned Severity : 3;
83   unsigned IsUser : 1;
84   unsigned IsPragma : 1;
85   unsigned HasNoWarningAsError : 1;
86   unsigned HasNoErrorAsFatal : 1;
87 
88 public:
Make(diag::Severity Severity,bool IsUser,bool IsPragma)89   static DiagnosticMapping Make(diag::Severity Severity, bool IsUser,
90                                 bool IsPragma) {
91     DiagnosticMapping Result;
92     Result.Severity = (unsigned)Severity;
93     Result.IsUser = IsUser;
94     Result.IsPragma = IsPragma;
95     Result.HasNoWarningAsError = 0;
96     Result.HasNoErrorAsFatal = 0;
97     return Result;
98   }
99 
getSeverity()100   diag::Severity getSeverity() const { return (diag::Severity)Severity; }
setSeverity(diag::Severity Value)101   void setSeverity(diag::Severity Value) { Severity = (unsigned)Value; }
102 
isUser()103   bool isUser() const { return IsUser; }
isPragma()104   bool isPragma() const { return IsPragma; }
105 
hasNoWarningAsError()106   bool hasNoWarningAsError() const { return HasNoWarningAsError; }
setNoWarningAsError(bool Value)107   void setNoWarningAsError(bool Value) { HasNoWarningAsError = Value; }
108 
hasNoErrorAsFatal()109   bool hasNoErrorAsFatal() const { return HasNoErrorAsFatal; }
setNoErrorAsFatal(bool Value)110   void setNoErrorAsFatal(bool Value) { HasNoErrorAsFatal = Value; }
111 };
112 
113 /// \brief Used for handling and querying diagnostic IDs.
114 ///
115 /// Can be used and shared by multiple Diagnostics for multiple translation units.
116 class DiagnosticIDs : public RefCountedBase<DiagnosticIDs> {
117 public:
118   /// \brief The level of the diagnostic, after it has been through mapping.
119   enum Level {
120     Ignored, Note, Remark, Warning, Error, Fatal
121   };
122 
123 private:
124   /// \brief Information for uniquing and looking up custom diags.
125   diag::CustomDiagInfo *CustomDiagInfo;
126 
127 public:
128   DiagnosticIDs();
129   ~DiagnosticIDs();
130 
131   /// \brief Return an ID for a diagnostic with the specified format string and
132   /// level.
133   ///
134   /// If this is the first request for this diagnostic, it is registered and
135   /// created, otherwise the existing ID is returned.
136 
137   // FIXME: Replace this function with a create-only facilty like
138   // createCustomDiagIDFromFormatString() to enforce safe usage. At the time of
139   // writing, nearly all callers of this function were invalid.
140   unsigned getCustomDiagID(Level L, StringRef FormatString);
141 
142   //===--------------------------------------------------------------------===//
143   // Diagnostic classification and reporting interfaces.
144   //
145 
146   /// \brief Given a diagnostic ID, return a description of the issue.
147   StringRef getDescription(unsigned DiagID) const;
148 
149   /// \brief Return true if the unmapped diagnostic levelof the specified
150   /// diagnostic ID is a Warning or Extension.
151   ///
152   /// This only works on builtin diagnostics, not custom ones, and is not
153   /// legal to call on NOTEs.
154   static bool isBuiltinWarningOrExtension(unsigned DiagID);
155 
156   /// \brief Return true if the specified diagnostic is mapped to errors by
157   /// default.
158   static bool isDefaultMappingAsError(unsigned DiagID);
159 
160   /// \brief Determine whether the given built-in diagnostic ID is a Note.
161   static bool isBuiltinNote(unsigned DiagID);
162 
163   /// \brief Determine whether the given built-in diagnostic ID is for an
164   /// extension of some sort.
isBuiltinExtensionDiag(unsigned DiagID)165   static bool isBuiltinExtensionDiag(unsigned DiagID) {
166     bool ignored;
167     return isBuiltinExtensionDiag(DiagID, ignored);
168   }
169 
170   /// \brief Determine whether the given built-in diagnostic ID is for an
171   /// extension of some sort, and whether it is enabled by default.
172   ///
173   /// This also returns EnabledByDefault, which is set to indicate whether the
174   /// diagnostic is ignored by default (in which case -pedantic enables it) or
175   /// treated as a warning/error by default.
176   ///
177   static bool isBuiltinExtensionDiag(unsigned DiagID, bool &EnabledByDefault);
178 
179 
180   /// \brief Return the lowest-level warning option that enables the specified
181   /// diagnostic.
182   ///
183   /// If there is no -Wfoo flag that controls the diagnostic, this returns null.
184   static StringRef getWarningOptionForDiag(unsigned DiagID);
185 
186   /// \brief Return the category number that a specified \p DiagID belongs to,
187   /// or 0 if no category.
188   static unsigned getCategoryNumberForDiag(unsigned DiagID);
189 
190   /// \brief Return the number of diagnostic categories.
191   static unsigned getNumberOfCategories();
192 
193   /// \brief Given a category ID, return the name of the category.
194   static StringRef getCategoryNameFromID(unsigned CategoryID);
195 
196   /// \brief Return true if a given diagnostic falls into an ARC diagnostic
197   /// category.
198   static bool isARCDiagnostic(unsigned DiagID);
199 
200   /// \brief Enumeration describing how the emission of a diagnostic should
201   /// be treated when it occurs during C++ template argument deduction.
202   enum SFINAEResponse {
203     /// \brief The diagnostic should not be reported, but it should cause
204     /// template argument deduction to fail.
205     ///
206     /// The vast majority of errors that occur during template argument
207     /// deduction fall into this category.
208     SFINAE_SubstitutionFailure,
209 
210     /// \brief The diagnostic should be suppressed entirely.
211     ///
212     /// Warnings generally fall into this category.
213     SFINAE_Suppress,
214 
215     /// \brief The diagnostic should be reported.
216     ///
217     /// The diagnostic should be reported. Various fatal errors (e.g.,
218     /// template instantiation depth exceeded) fall into this category.
219     SFINAE_Report,
220 
221     /// \brief The diagnostic is an access-control diagnostic, which will be
222     /// substitution failures in some contexts and reported in others.
223     SFINAE_AccessControl
224   };
225 
226   /// \brief Determines whether the given built-in diagnostic ID is
227   /// for an error that is suppressed if it occurs during C++ template
228   /// argument deduction.
229   ///
230   /// When an error is suppressed due to SFINAE, the template argument
231   /// deduction fails but no diagnostic is emitted. Certain classes of
232   /// errors, such as those errors that involve C++ access control,
233   /// are not SFINAE errors.
234   static SFINAEResponse getDiagnosticSFINAEResponse(unsigned DiagID);
235 
236   /// \brief Get the set of all diagnostic IDs in the group with the given name.
237   ///
238   /// \param[out] Diags - On return, the diagnostics in the group.
239   /// \returns \c true if the given group is unknown, \c false otherwise.
240   bool getDiagnosticsInGroup(diag::Flavor Flavor, StringRef Group,
241                              SmallVectorImpl<diag::kind> &Diags) const;
242 
243   /// \brief Get the set of all diagnostic IDs.
244   void getAllDiagnostics(diag::Flavor Flavor,
245                          SmallVectorImpl<diag::kind> &Diags) const;
246 
247   /// \brief Get the diagnostic option with the closest edit distance to the
248   /// given group name.
249   static StringRef getNearestOption(diag::Flavor Flavor, StringRef Group);
250 
251 private:
252   /// \brief Classify the specified diagnostic ID into a Level, consumable by
253   /// the DiagnosticClient.
254   ///
255   /// The classification is based on the way the client configured the
256   /// DiagnosticsEngine object.
257   ///
258   /// \param Loc The source location for which we are interested in finding out
259   /// the diagnostic state. Can be null in order to query the latest state.
260   DiagnosticIDs::Level
261   getDiagnosticLevel(unsigned DiagID, SourceLocation Loc,
262                      const DiagnosticsEngine &Diag) const LLVM_READONLY;
263 
264   diag::Severity
265   getDiagnosticSeverity(unsigned DiagID, SourceLocation Loc,
266                         const DiagnosticsEngine &Diag) const LLVM_READONLY;
267 
268   /// \brief Used to report a diagnostic that is finally fully formed.
269   ///
270   /// \returns \c true if the diagnostic was emitted, \c false if it was
271   /// suppressed.
272   bool ProcessDiag(DiagnosticsEngine &Diag) const;
273 
274   /// \brief Used to emit a diagnostic that is finally fully formed,
275   /// ignoring suppression.
276   void EmitDiag(DiagnosticsEngine &Diag, Level DiagLevel) const;
277 
278   /// \brief Whether the diagnostic may leave the AST in a state where some
279   /// invariants can break.
280   bool isUnrecoverable(unsigned DiagID) const;
281 
282   friend class DiagnosticsEngine;
283 };
284 
285 }  // end namespace clang
286 
287 #endif
288