Re: [PATCH v6] rust: kernel: add support for bits/genmask macros

[Alexandre Courbot]

On Mon Jun 16, 2025 at 11:45 PM JST, Daniel Almeida wrote:
>
>
>> On 16 Jun 2025, at 11:42, Daniel Almeida <daniel.almeida@xxxxxxxxxxxxx> wrote:
>> 
>> Hi Boqun,
>> 
>>> 
>>> We should tell/educate people to do the right thing, if a..b is not
>>> inclusive in Rust, then we should treat them as non-inclusive in Rust
>>> kernel code. Otherwise you create confusion for no reason. My assumption
>>> is that most people will ask "what's the right way to do this" first
>>> instead of replicating the old way.
>>> 
>>> Regards,
>>> Boqun
>>> 
>> 
>> This is just my opinion, of course:
>> 
>> I _hardly_ believe this will be the case. When people see genmask and two
>> numbers, they expect the range to be inclusive, full stop (at least IMHO). That's how it has
>> worked for decades, so it’s only natural to expect this behavior to transfer over.
>> 
>> However, I do understand and agree with your point, and I will change the
>> implementation here to comply. Perhaps we can use some markdown to alert users?
>> 
>> — Daniel
>
> Or better yet, perhaps we should only support a..=b.

... or just drop the ranges and do as Daniel initially did, using two
arguments. But I agree with Boqun that we should not deviate from the
official interpretation of ranges if we use them - the fact that `Range`
is exclusive on its upper bound is documented and a property of the type
itself.