1  int gl;
       2  
       3  g (x)
       4  {
       5    gl = x;
       6    return 0;
       7  }
       8  
       9  f (x)
      10  {
      11    int a = ~x;
      12    while (a)
      13      a = g (a);
      14  }
      15  
      16  main ()
      17  {
      18    f (3);
      19    if (gl != -4)
      20      abort ();
      21    exit (0);
      22  }