error[E0120]: the `Drop` trait may only be implemented for local structs, enums, and unions --> $DIR/drop-foreign-fundamental.rs:16:15 | LL | impl Drop for Pin> { | ^^^^^^^^^^^^^^^^ must be a struct, enum, or union in the current crate error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0120`.