error[E0277]: the trait bound `Dst: zerocopy::Immutable` is not satisfied --> tests/ui-nightly/transmute-ref-dst-not-nocell.rs:23:33 | 23 | const DST_NOT_IMMUTABLE: &Dst = transmute_ref!(&AU16(0)); | ^^^^^^^^^^^^^^^^^^^^^^^^ | | | the trait `zerocopy::Immutable` is not implemented for `Dst` | required by a bound introduced by this call | = note: Consider adding `#[derive(Immutable)]` to `Dst` = help: the following other types implement trait `zerocopy::Immutable`: &T &mut T () *const T *mut T AU16 Box F32 and $N others note: required by a bound in `AssertDstIsImmutable` --> tests/ui-nightly/transmute-ref-dst-not-nocell.rs:23:33 | 23 | const DST_NOT_IMMUTABLE: &Dst = transmute_ref!(&AU16(0)); | ^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `AssertDstIsImmutable` = note: this error originates in the macro `transmute_ref` (in Nightly builds, run with -Z macro-backtrace for more info)