#[inline(always)]
pub unsafe fn as_bytes_mut(&mut self) -> &mut [u8] {
// SAFETY: the cast from `&str` to `&[u8]` is safe since `str`
- // has the same layout as `&[u8]` (only libstd can make this guarantee).
+ // has the same layout as `&[u8]` (only std can make this guarantee).
// The pointer dereference is safe since it comes from a mutable reference which
// is guaranteed to be valid for writes.
unsafe { &mut *(self as *mut str as *mut [u8]) }