1  static int f (int a)
       2  {
       3    if (a == 0)
       4      return 0;
       5    do
       6      if (a & 128)
       7        return 1;
       8    while (f (0));
       9    return 0;
      10  }
      11  
      12  int main(void)
      13  {
      14    if (f (~128))
      15      abort ();
      16    exit (0);
      17  }