error[E0277]: the trait bound `Struct: PinnedDrop` is not satisfied
   --> $DIR/forget-pinned-drop-impl.rs:3:15
    |
3   | #[pin_project(PinnedDrop)] //~ ERROR E0277
    |               ^^^^^^^^^^ the trait `PinnedDrop` is not implemented for `Struct`
    |
note: required by `pin_project::__private::PinnedDrop::drop`
   --> $DIR/lib.rs:186:9
    |
186 |         unsafe fn drop(self: Pin<&mut Self>);
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^