error[E0277]: the trait bound `T: TraitWithAssoc` is not satisfied
  --> $DIR/bound_reduction2.rs:10:1
   |
LL | type Foo<V> = impl Trait<V>;
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `TraitWithAssoc` is not implemented for `T`
   |
help: consider further restricting this bound
   |
LL | fn foo_desugared<T: TraitWithAssoc + TraitWithAssoc>(_: T) -> Foo<T::Assoc> {
   |                                    ^^^^^^^^^^^^^^^^

error: defining opaque type use does not fully define opaque type: generic parameter `V` is specified as concrete type `<T as TraitWithAssoc>::Assoc`
  --> $DIR/bound_reduction2.rs:18:1
   |
LL | / fn foo_desugared<T: TraitWithAssoc>(_: T) -> Foo<T::Assoc> {
LL | |     ()
LL | | }
   | |_^

error: could not find defining uses
  --> $DIR/bound_reduction2.rs:10:1
   |
LL | type Foo<V> = impl Trait<V>;
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: aborting due to 3 previous errors

For more information about this error, try `rustc --explain E0277`.