clang/test/Analysis/test-after-div-zero.c

   1 // RUN: %clang_analyze_cc1 -std=c99 -Dbool=_Bool -analyzer-checker=core,alpha.core.TestAfterDivZero -analyzer-output=text -verify -analyzer-config eagerly-assume=false %s
   2 // RUN: %clang_analyze_cc1 -x c++ -analyzer-checker=core,alpha.core.TestAfterDivZero -analyzer-output=text -verify -analyzer-config eagerly-assume=false %s
   3
   4 int var;
   5
   6 void err_eq(int x) {
   7   var = 77 / x; // expected-note {{Division with compared value made here}}
   8   if (x == 0) { } // expected-warning {{Value being compared against zero has already been used for division}}
   9 } // expected-note@-1 {{Value being compared against zero has already been used for division}}
  10
  11 void err_eq2(int x) {
  12   var = 77 / x; // expected-note {{Division with compared value made here}}
  13   if (0 == x) { } // expected-warning {{Value being compared against zero has already been used for division}}
  14 } // expected-note@-1 {{Value being compared against zero has already been used for division}}
  15
  16 void err_ne(int x) {
  17   var = 77 / x; // expected-note {{Division with compared value made here}}
  18   if (x != 0) { } // expected-warning {{Value being compared against zero has already been used for division}}
  19 } // expected-note@-1 {{Value being compared against zero has already been used for division}}
  20
  21 void err_ge(int x) {
  22   var = 77 / x; // expected-note {{Division with compared value made here}}
  23   if (x >= 0) { } // expected-warning {{Value being compared against zero has already been used for division}}
  24 } // expected-note@-1 {{Value being compared against zero has already been used for division}}
  25
  26 void err_le(int x) {
  27   var = 77 / x; // expected-note {{Division with compared value made here}}
  28   if (x <= 0) {} // expected-warning {{Value being compared against zero has already been used for division}}
  29 } // expected-note@-1 {{Value being compared against zero has already been used for division}}
  30
  31 void err_yes(int x) {
  32   var = 77 / x; // expected-note {{Division with compared value made here}}
  33   if (x) {} // expected-warning {{Value being compared against zero has already been used for division}}
  34 } // expected-note@-1 {{Value being compared against zero has already been used for division}}
  35 void err_not(int x) {
  36   var = 77 / x; // expected-note {{Division with compared value made here}}
  37   if (!x) {} // expected-warning {{Value being compared against zero has already been used for division}}
  38 } // expected-note@-1 {{Value being compared against zero has already been used for division}}
  39
  40 void err_pnot(int x) {
  41   int *y = &x;
  42   var = 77 / *y; // expected-note {{Division with compared value made here}}
  43   if (!x) {} // expected-warning {{Value being compared against zero has already been used for division}}
  44 } // expected-note@-1 {{Value being compared against zero has already been used for division}}
  45
  46 void err_pnot2(int x) {
  47   int *y = &x;
  48   var = 77 / x; // expected-note {{Division with compared value made here}}
  49   if (!*y) {} // expected-warning {{Value being compared against zero has already been used for division}}
  50 } // expected-note@-1 {{Value being compared against zero has already been used for division}}
  51
  52 void err_ppnot(int x) {
  53   int *y = &x;
  54   int **z = &y;
  55   var = 77 / **z; // expected-note {{Division with compared value made here}}
  56   if (!x) {} // expected-warning {{Value being compared against zero has already been used for division}}
  57 } // expected-note@-1 {{Value being compared against zero has already been used for division}}
  58
  59 void err_orig_checker(int x) {
  60   if (x != 0) // expected-note {{Assuming 'x' is equal to 0}} expected-note {{Taking false branch}}
  61     return;
  62   var = 77 / x; // expected-warning {{Division by zero}} expected-note {{Division by zero}}
  63   if (!x) {} // no-warning
  64 }
  65
  66 void ok_other(int x, int y) {
  67   var = 77 / y;
  68   if (x == 0) {
  69   }
  70 }
  71
  72 void ok_assign(int x) {
  73   var = 77 / x;
  74   x = var / 77; // <- assignment => don't warn
  75   if (x == 0) {
  76   }
  77 }
  78
  79 void ok_assign2(int x) {
  80   var = 77 / x;
  81   x = var / 77; // <- assignment => don't warn
  82   if (0 == x) {
  83   }
  84 }
  85
  86 void ok_dec(int x) {
  87   var = 77 / x;
  88   x--; // <- assignment => don't warn
  89   if (x == 0) {
  90   }
  91 }
  92
  93 void ok_inc(int x) {
  94   var = 77 / x;
  95   x++; // <- assignment => don't warn
  96   if (x == 0) {
  97   }
  98 }
  99
 100 void do_something_ptr(int *x);
 101 void ok_callfunc_ptr(int x) {
 102   var = 77 / x;
 103   do_something_ptr(&x); // <- pass address of x to function => don't warn
 104   if (x == 0) {
 105   }
 106 }
 107
 108 void do_something(int x);
 109 void nok_callfunc(int x) {
 110   var = 77 / x; // expected-note {{Division with compared value made here}}
 111   do_something(x);
 112   if (x == 0) {} // expected-warning {{Value being compared against zero has already been used for division}}
 113 } // expected-note@-1 {{Value being compared against zero has already been used for division}}
 114
 115 void ok_if(int x) {
 116   if (x > 3)
 117     var = 77 / x;
 118   if (x == 0) {
 119   }
 120 }
 121
 122 void ok_if2(int x) {
 123   if (x < 3)
 124     var = 77 / x;
 125   if (x == 0) {
 126   } // TODO warn here
 127 }
 128
 129 void ok_pif(int x) {
 130   int *y = &x;
 131   if (x < 3)
 132     var = 77 / *y;
 133   if (x == 0) {
 134   } // TODO warn here
 135 }
 136
 137 int getValue(bool *isPositive);
 138 void use(int a);
 139 void foo(void) {
 140   bool isPositive;
 141   int x = getValue(&isPositive);
 142   if (isPositive) {
 143     use(5 / x);
 144   }
 145
 146   if (x == 0) {
 147   }
 148 }
 149
 150 int getValue2(void);
 151 void foo2(void) {
 152   int x = getValue2();
 153   int y = x;
 154
 155   use(5 / x); // expected-note {{Division with compared value made here}}
 156   if (y == 0) {} // expected-warning {{Value being compared against zero has already been used for division}}
 157 } // expected-note@-1 {{Value being compared against zero has already been used for division}}
 158
 159 void ok_while(int x) {
 160   int n = 100 / x;
 161   while (x != 0) { // <- do not warn
 162     x--;
 163   }
 164 }
 165
 166 void err_not2(int x, int y) {
 167   int v;
 168   var = 77 / x;
 169
 170   if (y)
 171     v = 0;
 172
 173   if (!x) {
 174   } // TODO warn here
 175 }
 176
 177 inline void inline_func(int x) {
 178   var = 77 / x; // expected-note {{Division with compared value made here}}
 179   if (x == 0) {} // expected-warning {{Value being compared against zero has already been used for division}}
 180 } // expected-note@-1 {{Value being compared against zero has already been used for division}}
 181
 182 void err_inline(int x) {
 183   var = 77 / x;
 184   inline_func(x); // expected-note {{Calling 'inline_func'}}
 185   if (x == 0) {
 186   }
 187 }
 188
 189 inline void inline_func2(int x) {}
 190
 191 void err_inline2(int x) {
 192   var = 77 / x; // expected-note {{Division with compared value made here}}
 193   inline_func2(x);
 194   if (x == 0) {} // expected-warning {{Value being compared against zero has already been used for division}}
 195 } // expected-note@-1 {{Value being compared against zero has already been used for division}}
 196
 197 inline void inline_func3(int x) {
 198   var = 77 / x;
 199 }
 200 void ok_inline(int x) {
 201   var = 77 / x; // expected-note {{Division with compared value made here}}
 202   inline_func3(x);
 203   if (x == 0) {} // expected-warning {{Value being compared against zero has already been used for division}}
 204 } // expected-note@-1 {{Value being compared against zero has already been used for division}}