1  extern __attribute__ ((__noreturn__)) void exit(int);
       2  extern __attribute__ ((__noreturn__)) void abort(void);
       3  __attribute__ ((__noinline__))
       4  int
       5  add512(int a, int *b)
       6  {
       7    int c = a + 512;
       8    if (c != 0)
       9      *b = a;
      10    return c;
      11  }
      12  
      13  __attribute__ ((__noinline__))
      14  int
      15  add513(int a, int *b)
      16  {
      17    int c = a + 513;
      18    if (c == 0)
      19      *b = a;
      20    return c;
      21  }
      22  
      23  int main(void)
      24  {
      25    int b0 = -1;
      26    int b1 = -1;
      27    if (add512(-512, &b0) != 0 || b0 != -1 || add513(-513, &b1) != 0 || b1 != -513)
      28      abort ();
      29    exit (0);
      30  }