error[E0621]: explicit lifetime required in the type of `cont` --> $DIR/issue-13058.rs:14:21 | LL | fn check<'r, I: Iterator, T: Itble<'r, usize, I>>(cont: &T) -> bool | -- help: add explicit lifetime `'r` to the type of `cont`: `&'r T` LL | { LL | let cont_iter = cont.iter(); | ^^^^^^^^^^^ lifetime `'r` required error: aborting due to previous error For more information about this error, try `rustc --explain E0621`.