Re: [PATCH 0/2] kbuild: Switch from '-fms-extensions' to '-fms-anonymous-structs' when available

[Helge Deller]

On 2/23/26 20:38, Ard Biesheuvel wrote:
> On Mon, 23 Feb 2026, at 20:10, Nathan Chancellor wrote:
> > Hi all,
> >
> > The kernel enabled '-fms-extensions' in commit c4781dc3d1cf ("Kbuild:
> > enable -fms-extensions") in 6.19 to gain access to a Microsoft
> > (originally Plan 9) extension around including a tagged structure/union
> > anonymously in an other structure/union. Since then, Clang 23.0.0
> > (current main) has added a flag to enable only that extension, rather
> > than all Microsoft extensions, '-fms-anonymous-structs' [1]. Using this
> > narrower compiler option would have avoided the build error fixed by
> > commit a6773e6932cb ("jfs: Rename _inline to avoid conflict with clang's
> > '-fms-extensions'"). While these errors are not expected to be common,
> > using the narrower option when available has no drawbacks because the
> > kernel only cares about this extension in '-fms-extensions', no others.
> > While this could result in build errors for folks using
> > '-fms-anonymous-structs' if a developer uses another extension in
> > '-fms-extensions' (either intentionally or unintentionally), flagging
> > these uses for further scrutiny seems worthwhile.
> >
> > This series converts the build system to use that flag when it is
> > available. The first patch consolidates all of the C dialect flags into
> > a single variable to make future updates to the dialect flags less
> > painful, as updating the logic in every place that uses their custom
> > built C flags is getting cumbersome (and C23 is looming). The second
> > patch makes the actual switch.
> >
> > I would like Nicolas to carry this in the Kbuild tree for 7.1, please
> > provide Acks as necessary.
> >
> > [1]:
> > https://github.com/llvm/llvm-project/commit/c391efe6fb67329d8e2fd231692cc6b0ea902956
> >
> > ---
> > Nathan Chancellor (2):
> >        kbuild: Consolidate C dialect options
> >        kbuild: Use '-fms-anonymous-structs' if it is available
>
> Acked-by: Ard Biesheuvel <ardb@xxxxxxxxxx>

For the series:
Acked-by: Helge Deller <deller@xxxxxx>  # parisc

Thanks!
Helge