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