warning: the feature `type_alias_impl_trait` is incomplete and may not be safe to use and/or cause compiler crashes
  --> $DIR/bound_reduction2.rs:3:32
   |
LL | #![cfg_attr(full_tait, 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: non-defining opaque type use in defining scope
  --> $DIR/bound_reduction2.rs:18:46
   |
LL | fn foo_desugared<T: TraitWithAssoc>(_: T) -> Foo<T::Assoc> {
   |                                              ^^^^^^^^^^^^^
   |
note: used non-generic type `<T as TraitWithAssoc>::Assoc` for generic parameter
  --> $DIR/bound_reduction2.rs:12:10
   |
LL | type Foo<V> = impl Trait<V>;
   |          ^

error: aborting due to previous error; 1 warning emitted