clang/test/Analysis/inlining/path-notes.c

   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
   5 void zero(int **p) {
   6   *p = 0;
   7   // expected-note@-1 {{Null pointer value stored to 'a'}}
   8 }
   9
  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
  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(void);
  30
  31 void testInitCheck(void) {
  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
  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
  56 int *getZero(void) {
  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
  64 void testReturnZero(void) {
  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
  71 int testReturnZero2(void) {
  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
  78 void testInitZero(void) {
  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
  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
  96 void usePointer(int *p) {
  97   *p = 1; // expected-warning{{Dereference of null pointer}}
  98   // expected-note@-1 {{Dereference of null pointer}}
  99 }
 100
 101 void testUseOfNullPointer(void) {
 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
 112 void setFieldToNull(struct X *x) {
 113         x->p = 0; // expected-note {{Null pointer value stored to field 'p'}}
 114 }
 115
 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
 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
 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
 143 void boringCallee(void) {
 144 }
 145
 146 void interestingCallee(int *x) {
 147   *x = 0; // expected-note{{The value 0 is assigned to 'x'}}
 148   boringCallee(); // no-note
 149 }
 150
 151 int testBoringCalleeOfInterestingCallee(void) {
 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