rust/tests/ui/issues/issue-25549-multiple-drop.rs

34 lines
659 B
Rust

//@ run-pass
#![allow(unused_variables)]
struct Foo<'r>(&'r mut i32);
impl<'r> Drop for Foo<'r> {
fn drop(&mut self) {
*self.0 += 1;
}
}
trait Trait {}
impl<'r> Trait for Foo<'r> {}
struct Holder<T: ?Sized>(T);
fn main() {
let mut drops = 0;
{
let y = &Holder([Foo(&mut drops)]) as &Holder<[Foo]>;
// this used to cause an extra drop of the Foo instance
let x = &y.0;
}
assert_eq!(1, drops);
drops = 0;
{
let y = &Holder(Foo(&mut drops)) as &Holder<dyn Trait>;
// this used to cause an extra drop of the Foo instance
let x = &y.0;
}
assert_eq!(1, drops);
}