gcc/testsuite/gcc.dg/nested-vla-1.c

   1 /* { dg-do run } */
   2 /* { dg-options "-std=gnu99" } */
   3 /* { dg-require-effective-target trampolines } */
   4
   5
   6 int main()
   7 {
   8         int n = 1;
   9
  10         struct foo { char x[++n]; } bar(void) { struct foo r; return r; }
  11
  12         if (2 != n)
  13                 __builtin_abort();
  14
  15         if (2 != sizeof(bar()))
  16                 __builtin_abort();
  17
  18         n = 1;
  19
  20         struct bar { char x[++n]; } (*bar2p)(void);
  21         struct bar bar2(void) { struct bar r; return r; }
  22         bar2p = &bar2;
  23
  24         if (2 != n)
  25                 __builtin_abort();
  26
  27         if (2 != sizeof((*bar2p)()))
  28                 __builtin_abort();
  29
  30         n = 1;
  31
  32         struct str { char x[++n]; } *bar3(void)
  33         {
  34                 struct str* s = __builtin_malloc(sizeof(struct str));
  35                 if (!s)
  36                         __builtin_abort();
  37                 struct str t;
  38                 *s = t;
  39                 return s;
  40         }
  41
  42         if (2 != n)
  43                 __builtin_abort();
  44
  45         struct str* p;
  46
  47         if (2 != sizeof(*(p = bar3())))
  48                 __builtin_abort();
  49
  50         __builtin_free(p);
  51
  52         n = 1;
  53
  54         struct { char x[++n]; } *bar4(void) { }
  55
  56         if (2 != n)
  57                 __builtin_abort();
  58 #if 0
  59         // UB
  60         if (2 != sizeof(*bar4()))
  61                 __builtin_abort();
  62 #endif
  63 }
  64