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; | ^^^^^^^^^^^^^^^^^ ...so that the reference type `&'a T` does not outlive the data it points at error: aborting due to previous error For more information about this error, try `rustc --explain E0309`.