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//@ run-pass
#![allow(unused_assignments)]
// Drop works for union itself.
// FIXME(static_mut_refs): this could use an atomic
#![allow(static_mut_refs)]
use std::mem::ManuallyDrop;
struct S;
union U {
a: ManuallyDrop<S>
}
impl Drop for S {
fn drop(&mut self) {
unsafe { CHECK += 10; }
}
}
impl Drop for U {
fn drop(&mut self) {
unsafe { CHECK += 1; }
}
}
static mut CHECK: u8 = 0;
fn main() {
unsafe {
let mut u = U { a: ManuallyDrop::new(S) };
assert_eq!(CHECK, 0);
u = U { a: ManuallyDrop::new(S) };
assert_eq!(CHECK, 1); // union itself is assigned, union is dropped, field is not dropped
*u.a = S;
assert_eq!(CHECK, 11); // union field is assigned, field is dropped
}
}
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