1 // RUN: %clang_analyze_cc1 -analyzer-checker=core -analyzer-output=text -analyzer-config suppress-null-return-paths=false -verify %s
2 // RUN: %clang_analyze_cc1 -analyzer-checker=core -analyzer-output=plist-multi-file -analyzer-config suppress-null-return-paths=false %s -o %t.plist
3 // RUN: %normalize_plist <%t.plist | diff -ub %S/Inputs/expected-plists/path-notes.c.plist -
4 
zero(int ** p)5 void zero(int **p) {
6   *p = 0;
7   // expected-note@-1 {{Null pointer value stored to 'a'}}
8 }
9 
testZero(int * a)10 void testZero(int *a) {
11   zero(&a);
12   // expected-note@-1 {{Calling 'zero'}}
13   // expected-note@-2 {{Returning from 'zero'}}
14   *a = 1; // expected-warning{{Dereference of null pointer}}
15   // expected-note@-1 {{Dereference of null pointer (loaded from variable 'a')}}
16 }
17 
testCheck(int * a)18 void testCheck(int *a) {
19   if (a) {
20     // expected-note@-1 + {{Assuming 'a' is null}}
21     // expected-note@-2 + {{Taking false branch}}
22     ;
23   }
24   *a = 1; // expected-warning{{Dereference of null pointer}}
25   // expected-note@-1 {{Dereference of null pointer (loaded from variable 'a')}}
26 }
27 
28 
29 int *getPointer();
30 
testInitCheck()31 void testInitCheck() {
32   int *a = getPointer();
33   // expected-note@-1 {{'a' initialized here}}
34   if (a) {
35     // expected-note@-1 + {{Assuming 'a' is null}}
36     // expected-note@-2 + {{Taking false branch}}
37     ;
38   }
39   *a = 1; // expected-warning{{Dereference of null pointer}}
40   // expected-note@-1 {{Dereference of null pointer (loaded from variable 'a')}}
41 }
42 
testStoreCheck(int * a)43 void testStoreCheck(int *a) {
44   a = getPointer();
45   // expected-note@-1 {{Value assigned to 'a'}}
46   if (a) {
47     // expected-note@-1 + {{Assuming 'a' is null}}
48     // expected-note@-2 + {{Taking false branch}}
49     ;
50   }
51   *a = 1; // expected-warning{{Dereference of null pointer}}
52   // expected-note@-1 {{Dereference of null pointer (loaded from variable 'a')}}
53 }
54 
55 
getZero()56 int *getZero() {
57   int *p = 0;
58   // expected-note@-1 + {{'p' initialized to a null pointer value}}
59   // ^ This note checks that we add a second visitor for the return value.
60   return p;
61   // expected-note@-1 + {{Returning null pointer (loaded from 'p')}}
62 }
63 
testReturnZero()64 void testReturnZero() {
65   *getZero() = 1; // expected-warning{{Dereference of null pointer}}
66   // expected-note@-1 {{Calling 'getZero'}}
67   // expected-note@-2 {{Returning from 'getZero'}}
68   // expected-note@-3 {{Dereference of null pointer}}
69 }
70 
testReturnZero2()71 int testReturnZero2() {
72   return *getZero(); // expected-warning{{Dereference of null pointer}}
73   // expected-note@-1 {{Calling 'getZero'}}
74   // expected-note@-2 {{Returning from 'getZero'}}
75   // expected-note@-3 {{Dereference of null pointer}}
76 }
77 
testInitZero()78 void testInitZero() {
79   int *a = getZero();
80   // expected-note@-1 {{Calling 'getZero'}}
81   // expected-note@-2 {{Returning from 'getZero'}}
82   // expected-note@-3 {{'a' initialized to a null pointer value}}
83   *a = 1; // expected-warning{{Dereference of null pointer}}
84   // expected-note@-1 {{Dereference of null pointer (loaded from variable 'a')}}
85 }
86 
testStoreZero(int * a)87 void testStoreZero(int *a) {
88   a = getZero();
89   // expected-note@-1 {{Calling 'getZero'}}
90   // expected-note@-2 {{Returning from 'getZero'}}
91   // expected-note@-3 {{Null pointer value stored to 'a'}}
92   *a = 1; // expected-warning{{Dereference of null pointer}}
93   // expected-note@-1 {{Dereference of null pointer (loaded from variable 'a')}}
94 }
95 
usePointer(int * p)96 void usePointer(int *p) {
97   *p = 1; // expected-warning{{Dereference of null pointer}}
98   // expected-note@-1 {{Dereference of null pointer}}
99 }
100 
testUseOfNullPointer()101 void testUseOfNullPointer() {
102   // Test the case where an argument expression is itself a call.
103   usePointer(getZero());
104   // expected-note@-1 {{Calling 'getZero'}}
105   // expected-note@-2 {{Returning from 'getZero'}}
106   // expected-note@-3 {{Passing null pointer value via 1st parameter 'p'}}
107   // expected-note@-4 {{Calling 'usePointer'}}
108 }
109 
110 struct X { char *p; };
111 
setFieldToNull(struct X * x)112 void setFieldToNull(struct X *x) {
113 	x->p = 0; // expected-note {{Null pointer value stored to field 'p'}}
114 }
115 
testSetFieldToNull(struct X * x)116 int testSetFieldToNull(struct X *x) {
117   setFieldToNull(x); // expected-note {{Calling 'setFieldToNull'}}
118                      // expected-note@-1{{Returning from 'setFieldToNull'}}
119   return *x->p;
120   // expected-warning@-1 {{Dereference of null pointer (loaded from field 'p')}}
121   // expected-note@-2 {{Dereference of null pointer (loaded from field 'p')}}
122 }
123 
124 struct Outer {
125   struct Inner {
126     int *p;
127   } inner;
128 };
129 
test(struct Outer * wrapperPtr)130 void test(struct Outer *wrapperPtr) {
131   wrapperPtr->inner.p = 0;  // expected-note {{Null pointer value stored to field 'p'}}
132   *wrapperPtr->inner.p = 1; //expected-warning {{Dereference of null pointer (loaded from field 'p')}}
133                             // expected-note@-1 {{Dereference of null pointer (loaded from field 'p')}}
134 }
135 
test4(int ** p)136 void test4(int **p) {
137   if (*p) return; // expected-note {{Taking false branch}}
138                   // expected-note@-1 {{Assuming pointer value is null}}
139   **p = 1; // expected-warning {{Dereference of null pointer}}
140            // expected-note@-1 {{Dereference of null pointer}}
141 }
142 
boringCallee()143 void boringCallee() {
144 }
145 
interestingCallee(int * x)146 void interestingCallee(int *x) {
147   *x = 0; // expected-note{{The value 0 is assigned to 'x'}}
148   boringCallee(); // no-note
149 }
150 
testBoringCalleeOfInterestingCallee()151 int testBoringCalleeOfInterestingCallee() {
152   int x;
153   interestingCallee(&x); // expected-note{{Calling 'interestingCallee'}}
154                          // expected-note@-1{{Returning from 'interestingCallee'}}
155   return 1 / x; // expected-warning{{Division by zero}}
156                 // expected-note@-1{{Division by zero}}
157 }
158 
159