error[E0119]: conflicting implementations of trait `_::_pin_project::__private::PinnedDrop` for type `S`
  --> tests/ui/pinned_drop/pinned-drop-no-attr-arg.rs:12:1
   |
5  | #[pin_project]
   | -------------- first implementation here
...
12 | impl PinnedDrop for S {
   | ^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `S`