error[E0277]: the trait bound `B: Bar` is not satisfied --> $DIR/issue-90400-2.rs:26:9 | LL | MyBaz(bar) | ^^^^^^^^^^ the trait `Bar` is not implemented for `B` | note: required because of the requirements on the impl of `Baz` for `MyBaz` --> $DIR/issue-90400-2.rs:31:14 | LL | impl Baz for MyBaz { | ^^^ ^^^^^^^^ help: consider restricting type parameter `B` | LL | type FooFn = impl Baz; | +++++ error: aborting due to previous error For more information about this error, try `rustc --explain E0277`.