gcc/testsuite/gcc.dg/memset-1.c

   1 /* { dg-do compile } */
   2 /* { dg-options "-O2" } */
   3
   4 typedef __SIZE_TYPE__ size_t;
   5
   6 extern void warn_memset_zero_len (void)
   7 __attribute__((__warning__ ("memset used with constant zero length parameter;"
   8                             " this could be due to transposed parameters")));
   9
  10 extern inline __attribute__((gnu_inline, always_inline, artificial)) void *
  11 memset (void *dest, int ch, size_t len)
  12 {
  13   if (__builtin_constant_p (len) && len == 0)
  14     {
  15       warn_memset_zero_len ();  /* { dg-warning "memset used with constant zero" } */
  16       return dest;
  17     }
  18   return __builtin_memset (dest, ch, len);
  19 }
  20
  21 char buf[10];
  22
  23 int
  24 main (void)
  25 {
  26   memset (buf, sizeof (buf), 0);
  27   return 0;
  28 }