Created attachment 856404 [details]
one preprocessed example

When building a kernel using gcc 12, I see a lot of:
> In file included from /home/latest/linux/include/linux/string.h:253,
>                  from /home/latest/linux/include/linux/bitmap.h:11,
>                  from /home/latest/linux/include/linux/cpumask.h:12,
>                  from /home/latest/linux/arch/x86/include/asm/cpumask.h:5,
>                  from /home/latest/linux/arch/x86/include/asm/msr.h:11,
>                  from /home/latest/linux/arch/x86/include/asm/processor.h:22,
>                  from /home/latest/linux/arch/x86/include/asm/cpufeature.h:5,
>                  from /home/latest/linux/arch/x86/include/asm/thread_info.h:53,
>                  from /home/latest/linux/include/linux/thread_info.h:60,
>                  from /home/latest/linux/arch/x86/include/asm/preempt.h:7,
>                  from /home/latest/linux/include/linux/preempt.h:78,
>                  from /home/latest/linux/include/linux/spinlock.h:55,
>                  from /home/latest/linux/include/linux/mmzone.h:8,
>                  from /home/latest/linux/include/linux/gfp.h:6,
>                  from /home/latest/linux/include/linux/mm.h:7,
>                  from /home/latest/linux/mm/swapfile.c:9:
> /home/latest/linux/include/linux/fortify-string.h: In function ���������memcmp���������:
> /home/latest/linux/include/linux/fortify-string.h:391:5: warning: infinite recursion detected [-Winfinite-recursion]
>   391 | int memcmp(const void * const POS0 p, const void * const POS0 q, __kernel_size_t size)
>       |     ^~~~~~
> /home/latest/linux/include/linux/fortify-string.h:44:33: note: recursive call
>    44 | #define __underlying_memcmp     __builtin_memcmp
>       |                                 ^
> /home/latest/linux/include/linux/fortify-string.h:404:16: note: in expansion of macro ���������__underlying_memcmp���������
>   404 |         return __underlying_memcmp(p, q, size);
>       |                ^~~~~~~~~~~~~~~~~~~

It's like this:
#define __underlying_memcmp     __builtin_memcmp

__FORTIFY_INLINE __diagnose_as(__builtin_memcmp, 1, 2, 3)
int memcmp(const void * const POS0 p, const void * const POS0 q,
__kernel_size_t size)
{
...
        return __underlying_memcmp(p, q, size);
}

I suppose it's a gcc bug...