23 lines
510 B
Rust
23 lines
510 B
Rust
// In contrast to `region-escape-via-bound-invariant`, in this case we
|
|
// *can* return a value of type `&'x u32`, even though `'x` does not
|
|
// appear in the bounds. This is because `&` is contravariant, and so
|
|
// we are *actually* returning a `&'y u32`.
|
|
//
|
|
// See https://github.com/rust-lang/rust/issues/46541 for more details.
|
|
|
|
//@ run-pass
|
|
|
|
#![allow(dead_code)]
|
|
|
|
trait Trait<'a> { }
|
|
|
|
impl<'a, 'b> Trait<'b> for &'a u32 { }
|
|
|
|
fn foo<'x, 'y>(x: &'x u32) -> impl Trait<'y>
|
|
where 'x: 'y
|
|
{
|
|
x
|
|
}
|
|
|
|
fn main() { }
|