rust/tests/ui/union/union-manuallydrop-rpass.rs
2024-02-16 20:02:50 +00:00

42 lines
635 B
Rust

//@ run-pass
#![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>>());
}