error[E0119]: conflicting implementations of trait `pin_project::__private::PinnedDrop` for type `S`:
  --> $DIR/pinned-drop-no-attr-arg.rs:11:1
   |
4  | #[pin_project]
   | -------------- first implementation here
...
11 | impl PinnedDrop for S {
   | ^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `S`