error: lifetime may not live long enough
  --> $DIR/mir_check_cast_unsize.rs:6:5
   |
LL | fn bar<'a>(x: &'a u32) -> &'static dyn Debug {
   |        -- lifetime `'a` defined here
LL |     x
   |     ^ returning this value requires that `'a` must outlive `'static`
   |
help: to declare that the trait object captures data from argument `x`, you can add an explicit `'a` lifetime bound
   |
LL | fn bar<'a>(x: &'a u32) -> &'static dyn Debug + 'a {
   |                                              ++++

error: aborting due to 1 previous error