| // Copyright 2016 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| // 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)] |
| #![feature(in_band_lifetimes)] |
| #![feature(nll)] |
| |
| trait Trait<'a> { } |
| |
| impl Trait<'b> for &'a u32 { } |
| |
| fn foo(x: &'x u32) -> impl Trait<'y> |
| where 'x: 'y |
| { |
| x |
| } |
| |
| fn main() { } |
