error[E0309]: the parameter type `T` may not live long enough
  --> $DIR/wf-impl-associated-type-region.rs:10:5
   |
LL | impl<'a, T> Foo<'a> for T {
   |          - help: consider adding an explicit lifetime bound `T: 'a`...
LL |     type Bar = &'a T;
   |     ^^^^^^^^^^^^^^^^^
   |
note: ...so that the reference type `&'a T` does not outlive the data it points at
  --> $DIR/wf-impl-associated-type-region.rs:10:5
   |
LL |     type Bar = &'a T;
   |     ^^^^^^^^^^^^^^^^^

error: aborting due to previous error

For more information about this error, try `rustc --explain E0309`.