1  struct foo { int a, b, c; };
       2  
       3  void
       4  brother (int a, int b, int c)
       5  {
       6    if (a)
       7      abort ();
       8  }
       9  
      10  void
      11  sister (struct foo f, int b, int c)
      12  {
      13    brother ((f.b == b), b, c);
      14  }
      15  
      16  int
      17  main ()
      18  {
      19    struct foo f = { 7, 8, 9 };
      20    sister (f, 1, 2);
      21    exit (0);
      22  }