gcc/testsuite/gcc.dg/gnu23-empty-init-1.c

   1 /* Test C23 support for empty initializers: valid use cases with GNU
   2    extensions.  */
   3 /* { dg-do run } */
   4 /* { dg-options "-std=gnu23" } */
   5
   6 extern void exit (int);
   7 extern void abort (void);
   8
   9 void
  10 f (int a)
  11 {
  12   struct s { volatile int x[a]; };
  13   struct s b = {};
  14   for (int i = 0; i < a; i++)
  15     if (b.x[i] != 0)
  16       abort ();
  17   /* Overwrite contents of b.x before second call to make it more likely stack
  18      contents are nonzero if proper initialization did not occur.  */
  19   for (int i = 0; i < a; i++)
  20     b.x[i] = -1;
  21 }
  22
  23 int
  24 main (void)
  25 {
  26   f (100);
  27   f (100);
  28   exit (0);
  29 }