ices/77987.rs: fixed with errors

[github-actions]

Issue: rust-lang/rust#77987

#![feature(type_alias_impl_trait)]

trait Foo<T> {}
impl<T, U> Foo<T> for U {}

type Scope = impl Foo<()>;

#[allow(unused)]
fn infer_scope() -> Scope {
    ()
}

#[allow(unused)]
fn ice() -> impl Foo<Scope> {
    loop {}
}

fn main() {}

=== stdout ===
=== stderr ===
error[E0658]: `impl Trait` in type aliases is unstable
 --> /home/runner/work/glacier/glacier/ices/77987.rs:6:14
  |
6 | type Scope = impl Foo<()>;
  |              ^^^^^^^^^^^^
  |
  = note: see issue #63063 <https://github.com/rust-lang/rust/issues/63063> for more information
  = help: add `#![feature(min_type_alias_impl_trait)]` to the crate attributes to enable

warning: the feature `type_alias_impl_trait` is incomplete and may not be safe to use and/or cause compiler crashes
 --> /home/runner/work/glacier/glacier/ices/77987.rs:1:12
  |
1 | #![feature(type_alias_impl_trait)]
  |            ^^^^^^^^^^^^^^^^^^^^^
  |
  = note: `#[warn(incomplete_features)]` on by default
  = note: see issue #63063 <https://github.com/rust-lang/rust/issues/63063> for more information

error: aborting due to previous error; 1 warning emitted

For more information about this error, try `rustc --explain E0658`.
==============