ICE from higher ranked subtyping

[matthewjasper]

The following code ICEs

fn f<'a, 'b, 'd, 'e> (
    x: for<'c> fn(
        fn(&'c fn(&'c ())),
        fn(&'c fn(&'c ())),
        fn(&'c fn(&'c ())),
        fn(&'c fn(&'c ())),
    )
) -> fn(
        fn(&'a fn(&'d ())),
        fn(&'b fn(&'d ())),
        fn(&'a fn(&'e ())),
        fn(&'b fn(&'e ())),
) {
    x
}

https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=169cdb4aaa19abce2baa2b45e876f797

[JohnTitor]

Triage: Fixed by #95565, marking as E-needs-test.