1 /* It is not clear whether this test is conforming.  See DR#236
2    http://www.open-std.org/jtc1/sc22/wg14/www/docs/dr_236.htm.  However,
3    there seems to be consensus that the presence of a union to aggregate
4    struct s1 and struct s2 should make it conforming.  */
5 struct s1 { double d; };
6 struct s2 { double d; };
7 union u { struct s1 x; struct s2 y; };
8 
f(struct s1 * a,struct s2 * b)9 double f(struct s1 *a, struct s2 *b)
10 {
11   a->d = 1.0;
12   return b->d + 1.0;
13 }
14 
main()15 int main()
16 {
17   union u a;
18   a.x.d = 0.0;
19   if (f (&a.x, &a.y) != 2.0)
20     abort ();
21   return 0;
22 }
23