[PATCH v22 00/27] remove use of VLAs for Windows

[David Marchand]

On Fri, Feb 7, 2025 at 3:23 PM Konstantin Ananyev
<konstantin.ananyev at huawei.com> wrote:
> > > As per guidance technical board meeting 2024/04/17. This series
> > > removes the use of VLAs from code built for Windows for all 3
> > > toolchains. If there are additional opportunities to convert VLAs
> > > to regular C arrays please provide the details for incorporation
> > > into the series.
> > >
> > > MSVC does not support VLAs, replace VLAs with standard C arrays
> > > or alloca(). alloca() is available for all toolchain/platform
> > > combinations officially supported by DPDK.
> >
> > - I have one concern wrt patch 7.
> > This changes the API/ABI of the RCU library.
> > ABI can't be broken in the 25.03 release.
> >
> > Since MSVC builds do not include RCU yet, I skipped this change and
> > adjusted this libray meson.build.
> >
> > Konstantin, do you think patch 7 could be rewritten to make use of
> > alloca() and avoid an API change?
> > https://patchwork.dpdk.org/project/dpdk/patch/1738805610-17507-8-git-send-email-andremue@linux.microsoft.com/
>
> I am not big fan of alloca() approach, but yes it is surely possible.

Can you please explain your reluctance?


> BTW, why it is considered ad API/ABI change?
> Because we introduce extra limit on max allowable size?

Yes, this is what was mentionned in the commitlog.


> If that would help somehow, we can make it even bigger: 1K or so.

Strictly speaking, it is still an API change.


-- 
David Marchand