error[E0204]: the trait `Copy` may not be implemented for this type --> $DIR/opt-in-copy.rs:7:15 | LL | but_i_cant: CantCopyThis, | ------------------------ this field does not implement `Copy` ... LL | impl Copy for IWantToCopyThis {} | ^^^^^^^^^^^^^^^ error[E0204]: the trait `Copy` may not be implemented for this type --> $DIR/opt-in-copy.rs:19:15 | LL | ButICant(CantCopyThisEither), | ------------------ this field does not implement `Copy` ... LL | impl Copy for IWantToCopyThisToo {} | ^^^^^^^^^^^^^^^^^^ error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0204`.