error: the following explicit lifetimes could be elided: 'a
  --> $DIR/needless_lifetimes_impl_trait.rs:15:5
   |
LL |     fn baz<'a>(&'a self) -> impl Foo + 'a {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
note: the lint level is defined here
  --> $DIR/needless_lifetimes_impl_trait.rs:1:9
   |
LL | #![deny(clippy::needless_lifetimes)]
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^

error: aborting due to previous error