scc

 1/* https://www.open-std.org/jtc1/sc22/wg14/issues/c90/issue0047.html */
 2
 3struct dummy;
 4
 5extern struct dummy dummy1;
 6
 7void *
 8fun(void)
 9{
10	return &dummy1;
11}
12
13int
14main()
15{
16	return fun() == 0;
17}