error[E0277]: `&A` cannot be safely transmuted into `&mut B` in the defining scope of `assert::Context` --> $DIR/recursive-wrapper-types-bit-compatible-mut.rs:24:49 | LL | assert::is_maybe_transmutable::<&'static A, &'static mut B>(); | ^^^^^^^^^^^^^^ `&A` is a shared reference, but `&mut B` is a unique reference | note: required by a bound in `is_maybe_transmutable` --> $DIR/recursive-wrapper-types-bit-compatible-mut.rs:10:14 | LL | pub fn is_maybe_transmutable() | --------------------- required by a bound in this function LL | where LL | Dst: BikeshedIntrinsicFrom | |__________^ required by this bound in `is_maybe_transmutable` error: aborting due to previous error For more information about this error, try `rustc --explain E0277`.