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

   1 // RUN: %clang_analyze_cc1 %s -analyzer-checker=core.NullDereference -analyzer-output=text -verify
   2 // RUN: %clang_analyze_cc1 %s -analyzer-checker=core.NullDereference -analyzer-output=plist -o %t
   3 // RUN: %normalize_plist <%t | diff -ub %S/Inputs/expected-plists/conditional-path-notes.c.plist -
   4
   5 void testCondOp(int *p) {
   6   int *x = p ? p : p;
   7   // expected-note@-1 {{Assuming 'p' is null}}
   8   // expected-note@-2 {{'?' condition is false}}
   9   // expected-note@-3 {{'x' initialized to a null pointer value}}
  10   *x = 1; // expected-warning{{Dereference of null pointer (loaded from variable 'x')}}
  11   // expected-note@-1 {{Dereference of null pointer (loaded from variable 'x')}}
  12 }
  13
  14 void testCondProblem(int *p) {
  15   if (p) return;
  16   // expected-note@-1 {{Assuming 'p' is null}}
  17   // expected-note@-2 {{Taking false branch}}
  18
  19   int x = *p ? 0 : 1; // expected-warning{{Dereference of null pointer (loaded from variable 'p')}}
  20   // expected-note@-1 {{Dereference of null pointer (loaded from variable 'p')}}
  21   (void)x;
  22 }
  23
  24 void testLHSProblem(int *p) {
  25   int x = !p ? *p : 1; // expected-warning{{Dereference of null pointer (loaded from variable 'p')}}
  26   // expected-note@-1 {{Assuming 'p' is null}}
  27   // expected-note@-2 {{'?' condition is true}}
  28   // expected-note@-3 {{Dereference of null pointer (loaded from variable 'p')}}
  29   (void)x;
  30 }
  31
  32 void testRHSProblem(int *p) {
  33   int x = p ? 1 : *p; // expected-warning{{Dereference of null pointer (loaded from variable 'p')}}
  34   // expected-note@-1 {{Assuming 'p' is null}}
  35   // expected-note@-2 {{'?' condition is false}}
  36   // expected-note@-3 {{Dereference of null pointer (loaded from variable 'p')}}
  37   (void)x;
  38 }
  39
  40 void testBinaryCondOp(int *p) {
  41   int *x = p ?: p;
  42   // expected-note@-1 {{'?' condition is false}}
  43   // expected-note@-2 {{'x' initialized to a null pointer value}}
  44   *x = 1; // expected-warning{{Dereference of null pointer (loaded from variable 'x')}}
  45   // expected-note@-1 {{Dereference of null pointer (loaded from variable 'x')}}
  46 }
  47
  48 void testBinaryLHSProblem(int *p) {
  49   if (p) return;
  50   // expected-note@-1 {{Assuming 'p' is null}}
  51   // expected-note@-2 {{Taking false branch}}
  52
  53   int x = *p ?: 1; // expected-warning{{Dereference of null pointer (loaded from variable 'p')}}
  54   // expected-note@-1 {{Dereference of null pointer (loaded from variable 'p')}}
  55   (void)x;
  56 }
  57
  58 void testDiagnosableBranch(int a) {
  59   if (a) {
  60     // expected-note@-1 {{Assuming 'a' is not equal to 0}}
  61     // expected-note@-2 {{Taking true branch}}
  62     *(volatile int *)0 = 1; // expected-warning{{Dereference of null pointer}}
  63     // expected-note@-1 {{Dereference of null pointer}}
  64   }
  65 }
  66
  67 void testDiagnosableBranchLogical(int a, int b) {
  68   if (a && b) {
  69     // expected-note@-1 {{Assuming 'a' is not equal to 0}}
  70     // expected-note@-2 {{Left side of '&&' is true}}
  71     // expected-note@-3 {{Assuming 'b' is not equal to 0}}
  72     // expected-note@-4 {{Taking true branch}}
  73     *(volatile int *)0 = 1; // expected-warning{{Dereference of null pointer}}
  74     // expected-note@-1 {{Dereference of null pointer}}
  75   }
  76 }
  77
  78 void testNonDiagnosableBranchArithmetic(int a, int b) {
  79   if (a - b) {
  80     // expected-note@-1 {{Taking true branch}}
  81     // expected-note@-2 {{Assuming the condition is true}}
  82     *(volatile int *)0 = 1; // expected-warning{{Dereference of null pointer}}
  83     // expected-note@-1 {{Dereference of null pointer}}
  84   }
  85 }
  86