error[E0271]: type mismatch resolving `<Concrete as Bar>::Other == Concrete`
  --> $DIR/issue-99348-impl-compatibility.rs:8:17
   |
LL | type Tait = impl Sized;
   |             ---------- the found opaque type
...
LL |     type Item = Concrete;
   |                 ^^^^^^^^ type mismatch resolving `<Concrete as Bar>::Other == Concrete`
   |
note: expected this to be `Concrete`
  --> $DIR/issue-99348-impl-compatibility.rs:13:18
   |
LL |     type Other = Tait;
   |                  ^^^^
   = note:   expected struct `Concrete`
           found opaque type `Tait`
note: required by a bound in `Foo::Item`
  --> $DIR/issue-99348-impl-compatibility.rs:17:20
   |
LL |     type Item: Bar<Other = Self>;
   |                    ^^^^^^^^^^^^ required by this bound in `Foo::Item`

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0271`.