gcc/testsuite/gcc.dg/tree-ssa/wnull-dereference.c

   1 /* { dg-do compile } */
   2 /* PR c/16531 */
   3 /* { dg-options "-O2 -fdelete-null-pointer-checks -Wnull-dereference" } */
   4 /* { dg-skip-if "" keeps_null_pointer_checks } */
   5
   6 #ifndef __cplusplus
   7 #define NULL (void *)0
   8 #else
   9 #define NULL nullptr
  10 #endif
  11
  12 struct t
  13 {
  14   int bar;
  15 };
  16
  17 struct t2
  18 {
  19   struct t *s;
  20 };
  21
  22 void test1 ()
  23 {
  24   struct t *s = NULL;
  25   s->bar = 1;  /* { dg-warning "null" } */
  26 }
  27
  28 void test2 (struct t *s)
  29 {
  30   if (s == NULL && s->bar > 2)  /* { dg-warning "null" } */
  31     return;
  32
  33   s->bar = 3;
  34 }
  35
  36 void test3 (struct t *s)
  37 {
  38   if (s != NULL || s->bar > 2)  /* { dg-warning "null" } */
  39     return;
  40
  41   s->bar = 3;  /* { dg-warning "null" } */
  42 }
  43
  44 int test4 (struct t *s)
  45 {
  46   if (s != NULL && s->bar > 2)  /* { dg-bogus "null" } */
  47     return 1;
  48   return 0;
  49 }
  50
  51 int test5 (struct t *s)
  52 {
  53   if (s == NULL || s->bar > 2)  /* { dg-bogus "null" } */
  54     return 1;
  55   return 0;
  56 }
  57
  58 int test6 (struct t2 *s)
  59 {
  60   if (s->s == 0 && s->s->bar == 0)  /* { dg-warning "null" } */
  61     return 1;
  62   return 0;
  63 }
  64
  65 int test7 (struct t *s)
  66 {
  67   s = 0;
  68   return s->bar;  /* { dg-warning "null" } */
  69 }
  70
  71 int test8 ()
  72 {
  73   return ((struct t *)0)->bar;  /* { dg-warning "null" } */
  74 }
  75
  76 void test9 (struct t **s)
  77 {
  78   if (s == 0)
  79     *s = 0;  /* { dg-warning "null" } */
  80 }
  81
  82