ref: c2ec983c04747f3174c2a46e474be1a4a4e0ff3b dir: /tests/execute/0043-union.c/
int main() { union { int a; int b; } u; u.a = 1; u.b = 3; if (u.a != 3 || u.b != 3) return 1; return 0; }