error[E0038]: the trait `X` is not dyn compatible --> $DIR/issue-67510-pass.rs:7:23 | LL | fn _func1<'a>(_x: Box=&'a ()>>) {} | ^^^^^^^^^^^^^^^^^^^ `X` is not dyn compatible | note: for a trait to be dyn compatible it needs to allow building a vtable for more information, visit --> $DIR/issue-67510-pass.rs:4:10 | LL | trait X { | - this trait is not dyn compatible... LL | type Y<'a>; | ^ ...because it contains the generic associated type `Y` = help: consider moving `Y` to another trait error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0038`.