1  foo (a, b)
       2  {
       3    unsigned x = 1;
       4  
       5    a += b;
       6    a += x;
       7    if (a <= 0)
       8      return 1;
       9    return 0;
      10  }
      11  
      12  main ()
      13  {
      14    printf ("%d\n", foo (1, ~0));
      15    printf ("%d\n", foo (0, ~0));
      16    printf ("%d\n", foo (-1, ~0));
      17  }