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Paper over an accidental regression

This commit is contained in:
Oli Scherer 2023-09-14 15:16:48 +00:00
parent df63c5f140
commit 0277184977
4 changed files with 24 additions and 15 deletions

View file

@ -461,7 +461,15 @@ fn check_opaque_meets_bounds<'tcx>(
}
match origin {
// Checked when type checking the function containing them.
hir::OpaqueTyOrigin::FnReturn(..) | hir::OpaqueTyOrigin::AsyncFn(..) => {}
hir::OpaqueTyOrigin::FnReturn(..) | hir::OpaqueTyOrigin::AsyncFn(..) => {
// HACK: this should also fall through to the hidden type check below, but the original
// implementation had a bug where equivalent lifetimes are not identical. This caused us
// to reject existing stable code that is otherwise completely fine. The real fix is to
// compare the hidden types via our type equivalence/relation infra instead of doing an
// identity check.
let _ = infcx.take_opaque_types();
return Ok(());
}
// Nested opaque types occur only in associated types:
// ` type Opaque<T> = impl Trait<&'static T, AssocTy = impl Nested>; `
// They can only be referenced as `<Opaque<T> as Trait<&'static T>>::AssocTy`.