validation/sm_switch.c

   1 //#include <stdlib.h>
   2
   3 struct foo {
   4         int a;
   5 };
   6
   7 struct foo *a;
   8 struct foo *b;
   9 struct foo *c;
  10 struct foo *d;
  11 int x;
  12
  13 void func (void)
  14 {
  15         a = 0;
  16         b = 0;
  17         c = 0;
  18         d = 0;
  19
  20         switch(x) {
  21         case 1:
  22                 a = returns_nonnull();
  23                 break;
  24         case 2:
  25                 b = returns_nonnull();
  26                 break;
  27         case 3:
  28                 c = returns_nonnull();
  29                 break;
  30         default:
  31                 d = returns_nonnull();
  32         }
  33
  34         switch(x) {
  35         case 1:
  36                 a->a = 1;
  37         case 2:
  38                 a->a = 2;
  39                 b->a = 3;
  40                 break;
  41         case 3:
  42                 c->a = 4;
  43                 break;
  44         case 4:
  45                 d->a = 5;
  46                 break;
  47         }
  48 }
  49 /*
  50  * check-name: Smatch switch handling
  51  * check-command: smatch sm_switch.c
  52  * check-known-to-fail
  53  *
  54  * check-output-start
  55 sm_switch.c:38 func(25) error: potential null derefence 'a'.
  56 sm_switch.c:39 func(26) error: potential null derefence 'b'.
  57  * check-output-end
  58  */