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>> >> pub mod mem; >> @@ -296,6 +300,13 @@ pub trait Io { >> /// Type of this I/O region. For untyped I/O regions, [`Region`] ty= pe can be used. >> type Type: ?Sized + KnownSize; >> >> + /// Get a [`View`] covering the entire region. >> + #[inline] >> + fn as_view(&self) -> View<'_, Self, Self::Type> { >> + // SAFETY: Trivially satisfied. > > What might be trivial to you is not necessarily obvious to others. > Please explain why we are satisfying safety requirements. This is what language model produces: Analysis: Io::as_view() =20 fn as_view(&self) -> View<'_, Self, Self::Type> { // SAFETY: Trivially satisfied unsafe { View::new_unchecked(self, self.as_ptr()) } } =20 The View invariants are: 1. ptr is aligned for T 2. ptr has same provenance as io.as_ptr() 3. ptr.byte_offset_from(io.as_ptr()) is between 0 to KnownSize::size(= io.as_ptr()) - KnownSize::size(ptr) =20 For as_view(): - ptr =3D self.as_ptr() which is Self::Type - Invariant 1: self.as_ptr() should be aligned for Self::Type - assum= ed true from the Io trait - Invariant 2: Same pointer, same provenance - trivially true - Invariant 3: ptr.byte_offset_from(io.as_ptr()) =3D 0, and we need 0= <=3D size_io - size_ptr which is 0 <=3D 0, true =20 The safety comment "Trivially satisfied" is correct. I think the verbosity here is really because we have the safety requirement listed item by item, rather than just defining a new concept. If we, for example, coin an idea of `IO valid pointers`, then we can just s= ay the `self.as_ptr()` is trivially I/O valid. Perhaps, for this case, we can use the "projection trivially satisfy the invariants" that I've already mentioned in the doc, and just write // SAFETY: This is an empty projection, so it trivially satisfies the // invariant. ? Best, Gary > > Otherwise looks good, with the above fixed, please add: > > Reviewed-by: Andreas Hindborg > > Best regards, > Andreas Hindborg