union U {
  struct {
      int x : 1;
      int y : 1;
  } test;
  int z;
} u;

void foo(const int& a){ cout << &a << endl; }

int main() {
 cout << &u.z << endl;
 foo(u.test.x);
 foo(u.test.y);
 return 0;
}

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