error: lifetime may not live long enough
  --> $DIR/implied_bounds_closure.rs:17:16
   |
LL | fn extend_lifetime<'a>(x: &'a str) -> &'static str {
   |                    -- lifetime `'a` defined here
LL |     let t = into_impl(x);
LL |     helper(|_| t)
   |                ^ returning this value requires that `'a` must outlive `'static`

error: aborting due to previous error