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// run-pass
// revisions: mirunsafeck thirunsafeck
// [thirunsafeck]compile-flags: -Z thir-unsafeck
#![allow(dead_code)]
use std::mem::needs_drop;
use std::mem::ManuallyDrop;
struct NeedDrop;
impl Drop for NeedDrop {
fn drop(&mut self) {}
}
union UnionOk1<T> {
empty: (),
value: ManuallyDrop<T>,
}
union UnionOk2 {
value: ManuallyDrop<NeedDrop>,
}
#[allow(dead_code)]
union UnionOk3<T: Copy> {
empty: (),
value: T,
}
trait Foo { }
trait ImpliesCopy : Copy { }
#[allow(dead_code)]
union UnionOk4<T: ImpliesCopy> {
value: T,
}
fn main() {
// NeedDrop should not make needs_drop true
assert!(!needs_drop::<UnionOk1<NeedDrop>>());
assert!(!needs_drop::<UnionOk3<&dyn Foo>>());
}
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