1__attribute__ ((__noinline__))
2char *sf(char *s, char *s0)
3{
4  asm ("");
5  while (*--s == '9')
6    if (s == s0)
7      {
8	*s = '0';
9	break;
10      }
11  ++*s++;
12  return s;
13}
14
15int main()
16{
17  char s[] = "999999";
18  char *x = sf (s+2, s);
19  if (x != s+1 || __builtin_strcmp (s, "199999") != 0)
20    __builtin_abort ();
21  return 0;
22}
23