Re: [PATCH for-4.15] arm: replace typeof() with __typeof__()

[Jan Beulich <jbeulich@xxxxxxxx>]

On 09.03.2021 22:27, Andrew Cooper wrote:
> On 08/03/2021 13:36, Elliott Mitchell wrote:
>> typeof() is available in Xen's build environment, which uses Xen's
>> compiler.  As these headers are public, they need strict standards
>> conformance.  Only __typeof__() is officially standardized.
>>
>> A compiler in standards conformance mode should report:
>>
>> warning: implicit declaration of function 'typeof' is invalid in C99
>> [-Wimplicit-function-declaration]
>>
>> (this has been observed with FreeBSD's kernel build environment)
>>
>> Based-on-patch-by: Julien Grall <julien@xxxxxxx>, Sun Oct 4 20:33:04 2015 
>> +0100
>> Signed-off-by: Elliott Mitchell <ehem+xen@xxxxxxx>
> 
> s!arm!xen/public! in the subject seeing as two thirds of the
> modifications are in non-ARM headers.
> 
> Acked-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> 
> This wants backporting as a build fix, so should be considered for 4.15
> at this point.
> 
> I wonder why our header checks don't pick this up.  Do we need to throw
> a -pedantic around?

That's a long-standing issue with the checking: For issues to be
found in macros, the macros would actually need to be used.

Jan