[rustc.git] / src / test / ui / impl-trait / multiple-lifetimes / error-handling.rs

#![feature(type_alias_impl_trait)]

#[derive(Clone)]
struct CopyIfEq<T, U>(T, U);

impl<T: Copy> Copy for CopyIfEq<T, T> {}

type E<'a, 'b> = impl Sized;

fn foo<'a, 'b, 'c>(x: &'static i32, mut y: &'a i32) -> E<'b, 'c> {
    let v = CopyIfEq::<*mut _, *mut _>(&mut { x }, &mut y);

    // This assignment requires that `x` and `y` have the same type due to the
    // `Copy` impl. The reason why we are using a copy to create a constraint
    // is that only borrow checking (not regionck in type checking) enforces
    // this bound.
    let u = v;
    let _: *mut &'a i32 = u.1;
    unsafe {
        let _: &'b i32 = *u.0;
        //~^ ERROR lifetime may not live long enough
    }
    u.0
}

fn main() {}
Commit	Line	Data
94222f64	1	#![feature(type_alias_impl_trait)]
dc9dc135 XL	2
	3	#[derive(Clone)]
	4	struct CopyIfEq<T, U>(T, U);
	5
	6	impl<T: Copy> Copy for CopyIfEq<T, T> {}
	7
416331ca	8	type E<'a, 'b> = impl Sized;
dc9dc135 XL	9
dc9dc135 XL	10	fn foo<'a, 'b, 'c>(x: &'static i32, mut y: &'a i32) -> E<'b, 'c> {
74b04a01 XL	11	let v = CopyIfEq::<mut _, mut _>(&mut { x }, &mut y);
	12
	13	// This assignment requires that `x` and `y` have the same type due to the
	14	// `Copy` impl. The reason why we are using a copy to create a constraint
	15	// is that only borrow checking (not regionck in type checking) enforces
	16	// this bound.
dc9dc135 XL	17	let u = v;
dc9dc135 XL	18	let _: *mut &'a i32 = u.1;
74b04a01 XL	19	unsafe {
	20	let _: &'b i32 = *u.0;
	21	//~^ ERROR lifetime may not live long enough
	22	}
dc9dc135 XL	23	u.0
	24	}
	25
	26	fn main() {}