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It is also safe because technically a > no-op. > > Reviewed-by: Alistair Popple > Reviewed-by: Gary Guo > Signed-off-by: Alexandre Courbot > --- > rust/kernel/transmute.rs | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/rust/kernel/transmute.rs b/rust/kernel/transmute.rs > index be5dbf3829e2..5711580c9f9b 100644 > --- a/rust/kernel/transmute.rs > +++ b/rust/kernel/transmute.rs > @@ -170,6 +170,10 @@ macro_rules! impl_frombytes { > } > > impl_frombytes! { > + // SAFETY: Inhabited ZSTs only have one possible bit pattern, and these two have no invariant. > + (), > + {} core::marker::PhantomData, > + > // SAFETY: All bit patterns are acceptable values of the types below. > u8, u16, u32, u64, usize, > i8, i16, i32, i64, isize, > @@ -230,6 +234,10 @@ macro_rules! impl_asbytes { > } > > impl_asbytes! { > + // SAFETY: Inhabited ZSTs only have one possible bit pattern, and these two have no invariant. Some nit: technically you can turn any ZST into bytes, even those with invariants or uninhabited. So while the comment is correct, it's kinda redundant for the object -> bytes direction :) No change required for this patch. Best, Gary > + (), > + {} core::marker::PhantomData, > + > // SAFETY: Instances of the following types have no uninitialized portions. > u8, u16, u32, u64, usize, > i8, i16, i32, i64, isize, >