Re: [PATCH v9] rust: add new macro for common bitflag operations

[Filipe Xavier]

On 1/30/26 2:25 AM, Miguel Ojeda wrote:

> On Sat, Jan 17, 2026 at 11:41 AM Filipe Xavier <felipeaggger@xxxxxxxxx> wrote:
> > We have seen a proliferation of mod_whatever::foo::Flags
> > being defined with essentially the same implementation
> > for BitAnd, BitOr, contains and etc.
> >
> > This macro aims to bring a solution for this,
> > allowing to generate these methods for user-defined structs.
> > With some use cases in KMS and upcoming GPU drivers.
> >
> > Link: https://rust-for-linux.zulipchat.com/#narrow/channel/288089-General/topic/We.20really.20need.20a.20common.20.60Flags.60.20type
> > Suggested-by: Daniel Almeida <daniel.almeida@xxxxxxxxxxxxx>
> > Suggested-by: Lyude Paul <lyude@xxxxxxxxxx>
> > Reviewed-by: Daniel Almeida <daniel.almeida@xxxxxxxxxxxxx>
> > Reviewed-by: Lyude Paul <lyude@xxxxxxxxxx>
> > Tested-by: Andreas Hindborg <a.hindborg@xxxxxxxxxx>
> > Reviewed-by: Andreas Hindborg <a.hindborg@xxxxxxxxxx>
> > Signed-off-by: Filipe Xavier <felipeaggger@xxxxxxxxx>
> So I was about to apply this one and I noticed a few bits (no need for
> a new version):
>
>    - This was added to the prelude -- I asked the team and they felt it
> wasn't needed, so I will remove it. We can always add it later on if
> needed.
Sounds good, no problem.
>    - Is `BitXorAssign<$flag> for $flags` missing for some reason? I will add:
>
>          impl ::core::ops::BitXorAssign<$flag> for $flags {
>              #[inline]
>              fn bitxor_assign(&mut self, rhs: $flag) {
>                  *self = *self ^ rhs;
>              }
>          }
>
>      This is why I like to have tests for every operator... I may open
> a good first issue about it :)

Regarding |BitXorAssign|, that was indeed an oversight on my part. 
Adding it makes perfect sense.

> I also fixed an intra-doc link and tweaked a couple other bits.

Thanks for the review and for taking the time with this.

Xavier

> Cheers,
> Miguel