Re: [PATCH] kbuild: hdrcheck: fix cross build with clang

[Arnd Bergmann]

On Fri, Feb 21, 2025, at 22:26, Nathan Chancellor wrote:
> On Fri, Feb 21, 2025 at 10:20:07PM +0100, Arnd Bergmann wrote:
>> From: Arnd Bergmann <arnd@xxxxxxxx>
>> 
>> The headercheck tries to call clang with a mix of compiler arguments
>> that don't include the target architecture. When building e.g. x86
>> headers on arm64, this produces a warning like
>> 
>>    clang: warning: unknown platform, assuming -mfloat-abi=soft
>> 
>> Add in the CLANG_FLAGS, which contain the target, in order to make it
>> build properly.
>> 
>> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
>
> This looks like a similar problem as the one fixed by
> commit 1b71c2fb04e7 ("kbuild: userprogs: fix bitsize and target
> detection on clang"), should it be addressed in the same manner
> (especially since I think the Fixes commit would be the same)? Given
> that the filter expression is the same, maybe it would be possible to
> unify them but that could happen as a follow up.

My bad, I actually had an old patch that addressed both issues
and then dropped it when the Thomas' patch made it into linux-next
but ended up picking my old change for usr/include/Makefile instead
of trying to understand the difference.

I'll send a v2 after some more build testing.

     Arnd