Re: [PATCH v2] rust: error: add missing error codes

From: Miguel Ojeda
Date: Tue May 09 2023 - 07:11:11 EST


On Tue, May 9, 2023 at 10:46 AM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> It depends on which arch you are building for. That's why we have
> per-platform errno.h files, the values are different for different ones.
> So you need to handle them all properly somehow. How is rust going to
> handle per-arch stuff like this?

We can do conditional compilation in the same file, possibly with a
Rust macro which takes a nice table that shows all arches at once.

We can also split into files like C and move it to each `arch/`, there
are a couple of approaches for this. This is best for `MAINTAINERS`,
although these headers almost never change, so it is not a big
advantage.

We could also automatically do everything based on the C headers, too.
Back then it felt to me like too much complexity for little gain,
given those C headers almost never change, but now it may be worth it.
Or, instead, having a test that verifies they are the same instead,
and that way we don't introduce complexity for the build itself.

Alice only needs `ERESTARTSYS` so far, as far as I understand, so
perhaps it is simplest to only add the rest of the non-generic ones
for the moment; and gather opinions on the approaches above meanwhile.

Cheers,
Miguel