1 # include <stddef.h>
2 
3 typedef struct _S { union { int i; struct { int m; } s; } u; } S;
4 
f()5 int f () {
6   size_t t;
7   int m;
8 
9   t = offsetof (S, u.i);
10   m = offsetof (S, u);
11   t = offsetof (S, u.s.m);
12   t = offsetof (S, u.s.k);
13   return m;
14 }
15