error[E0277]: the trait bound `(): Foo` is not satisfied --> $DIR/wf-foreign-fn-decl-ret.rs:11:25 | LL | pub fn lint_me() -> <() as Foo>::Assoc; | ^^^^^^^^^^^^^^^^^^ the trait `Foo` is not implemented for `()` error[E0277]: the trait bound `u32: Unsatisfied` is not satisfied --> $DIR/wf-foreign-fn-decl-ret.rs:14:32 | LL | pub fn lint_me_aswell() -> Bar; | ^^^^^^^^ the trait `Unsatisfied` is not implemented for `u32` | note: required by a bound in `Bar` --> $DIR/wf-foreign-fn-decl-ret.rs:4:19 | LL | pub struct Bar(T); | ^^^^^^^^^^^ required by this bound in `Bar` error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0277`.