1struct s 2{ 3 int a; 4 int b; 5 struct s *dummy; 6}; 7 8f (struct s *sp) 9{ 10 return sp && sp->a == -1 && sp->b == -1; 11} 12 13main () 14{ 15 struct s x; 16 x.a = x.b = -1; 17 if (f (&x) == 0) 18 abort (); 19 exit (0); 20} 21