error[E0277]: the trait bound `Rc: Copy` is not satisfied --> $DIR/union-generic.rs:8:13 | LL | union U { | ---------------- required by `U` ... LL | let u = U { a: Rc::new(0u32) }; | ^ the trait `Copy` is not implemented for `Rc` error[E0277]: the trait bound `Rc: Copy` is not satisfied --> $DIR/union-generic.rs:10:13 | LL | union U { | ---------------- required by `U` ... LL | let u = U::> { a: Default::default() }; | ^^^^^^^^^^^^ the trait `Copy` is not implemented for `Rc` error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0277`.