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//@ run-pass
#![allow(dead_code)]
#![allow(unused_variables)]
// Drop works for union itself.
#[derive(Copy, Clone)]
struct S;
union U {
a: u8
}
union W {
a: S,
}
union Y {
a: S,
}
impl Drop for U {
fn drop(&mut self) {
unsafe { CHECK += 1; }
}
}
impl Drop for W {
fn drop(&mut self) {
unsafe { CHECK += 1; }
}
}
static mut CHECK: u8 = 0;
fn main() {
unsafe {
assert_eq!(CHECK, 0);
{
let u = U { a: 1 };
}
assert_eq!(CHECK, 1); // 1, dtor of U is called
{
let w = W { a: S };
}
assert_eq!(CHECK, 2); // 2, dtor of W is called
{
let y = Y { a: S };
}
assert_eq!(CHECK, 2); // 2, Y has no dtor
{
let u2 = U { a: 1 };
std::mem::forget(u2);
}
assert_eq!(CHECK, 2); // 2, dtor of U *not* called for u2
}
}
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