validation/sm_switch2.c

   1 struct foo {
   2         int a;
   3 };
   4
   5 struct foo *a;
   6 struct foo *b;
   7 struct foo *c;
   8 struct foo *d;
   9 int x;
  10
  11 void func (void)
  12 {
  13         a = 0;
  14         b = 0;
  15         c = 0;
  16         d = 0;
  17
  18         if (x == 1)
  19                 a = some_func();
  20         else if (x == 2)
  21                 b = some_func();
  22         else if (x == 3)
  23                 c = some_func();
  24         else
  25                 d = some_func();
  26
  27         switch(x) {
  28         case 1:
  29                 a->a = 1;
  30         case 2:
  31                 a->a = 2;
  32                 b->a = 3;
  33                 break;
  34         case 3:
  35                 c->a = 4;
  36                 break;
  37         case 4:
  38                 d->a = 5;
  39                 break;
  40         }
  41 }
  42 /*
  43  * check-name: Smatch switch handling #2
  44  * check-command: smatch sm_switch2.c
  45  *
  46  * check-output-start
  47 sm_switch2.c:31 func() error: potential NULL dereference 'a'.
  48 sm_switch2.c:32 func() error: potential NULL dereference 'b'.
  49  * check-output-end
  50  */