error[E0637]: `'_` cannot be used here
  --> $DIR/issue-95305.rs:10:26
   |
LL | fn foo(x: &impl Foo<Item<'_> = u32>) { }
   |                          ^^ `'_` is a reserved lifetime name

error: aborting due to previous error

For more information about this error, try `rustc --explain E0637`.