error[E0277]: the trait bound `&u32: Foo` is not satisfied --> $DIR/issue-60218.rs:18:19 | LL | trigger_error(vec![], |x: &u32| x) | ------------- ^^^^^^ the trait `Foo` is not implemented for `&u32` | | | required by a bound introduced by this call | note: required by a bound in `trigger_error` --> $DIR/issue-60218.rs:13:72 | LL | pub fn trigger_error(iterable: I, functor: F) | ------------- required by a bound in this ... LL | for<'t> ::IntoIter, F> as Iterator>::Item: Foo, | ^^^ required by this bound in `trigger_error` error: aborting due to previous error For more information about this error, try `rustc --explain E0277`.