1 error[E0748]: found both positive and negative implementation of trait `std::ops::DerefMut` for type `&MyType<'_>`:
2 --> $DIR/pin-unsound-issue-66544-derefmut.rs:12:1
4 LL | impl<'a> DerefMut for &'a MyType<'a> {
5 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ positive implementation here
7 = note: negative implementation in crate `core`
9 error: aborting due to previous error
11 For more information about this error, try `rustc --explain E0748`.