rustc stack overflow: recursive associated types

[seanmonstar]

trait Foo {
    type Bar;
    fn foo(self) -> Self::Bar;
}

impl Foo for Box<Foo> {
    type Bar = <Self as Foo>::Bar;
    fn foo(self) -> <Self as Foo>::Bar {
        (*self).foo()
    }
}

[apoelstra]

I've encountered a variant of this bug (or is it another bug? please advise if so and I will post it separately):

pub struct Outer<T: Trait>(T);
pub struct Inner<'a>(&'a bool);

pub trait Trait {
    type Error;
    fn ready(self) -> Self::Error;
}

impl<'a> Trait for Inner<'a> {
    type Error = Outer<Inner<'a>>;
    fn ready(mut self) -> Outer<Inner<'a>> {}
}

If I remove the lifetime, the stack overflow no longer occurs.

[nham]

Seems to be a dupe of #21946

[arielb1]

@apoelstra's example was fixed in 1.4.