error[E0191]: the value of the associated type `A` (from the trait `Foo`) must be specified --> $DIR/issue-22434.rs:5:19 | LL | type A; | ------- `A` defined here ... LL | type I<'a> = &'a (Foo + 'a); | ^^^^^^^^ associated type `A` must be specified error: aborting due to previous error For more information about this error, try `rustc --explain E0191`.