/* { dg-do compile } */ /* { dg-options "-O2" } */ typedef __SIZE_TYPE__ size_t; extern void warn_memset_zero_len (void) __attribute__((__warning__ ("memset used with constant zero length parameter;" " this could be due to transposed parameters"))); extern inline __attribute__((gnu_inline, always_inline, artificial)) void * memset (void *dest, int ch, size_t len) { if (__builtin_constant_p (len) && len == 0) { warn_memset_zero_len (); /* { dg-warning "memset used with constant zero" } */ return dest; } return __builtin_memset (dest, ch, len); } char buf[10]; int main (void) { memset (buf, sizeof (buf), 0); return 0; }