scc

 1typedef struct {
 2	int a;
 3	union {
 4		int b1;
 5		int b2;
 6	};
 7	struct { union { struct { int c; }; struct {}; }; };
 8	struct {};
 9	struct {
10		int d;
11	};
12} s;
13
14int
15main()
16{
17	s v;
18	
19	v.a = 1;
20	v.b1 = 2;
21	v.c = 3;
22	v.d = 4;
23	
24	if (v.a != 1)
25		return 1;
26	if (v.b1 != 2 && v.b2 != 2)
27		return 2;
28	if (v.c != 3)
29		return 3;
30	if (v.d != 4)
31		return 4;
32	
33	return 0;
34}