1  foo (a)
       2  {
       3    return (a & (1 << 31)) != 0;
       4  }
       5  
       6  main ()
       7  {
       8    if (foo (0))
       9      puts ("foo");
      10    else
      11      puts ("bar");
      12    if (foo (~0))
      13      puts ("foo");
      14    else
      15      puts ("bar");
      16  }