error[E0477]: the type `&()` does not fulfill the required lifetime
  --> $DIR/gat-wf.rs:13:18
   |
LL |     type T<'a> = ();
   |                  ^^
   |
note: type must outlive the lifetime `'a` as defined here
  --> $DIR/gat-wf.rs:13:12
   |
LL |     type T<'a> = ();
   |            ^^

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0477`.