powerpc: io-defs.h:43:1: error: performing pointer arithmetic on a null pointer has undefined behavior [-Werror,-Wnull-pointer-arithmetic]

[Dan Carpenter]

On Tue, Apr 16, 2024 at 01:55:57PM +0200, Arnd Bergmann wrote:
> On Tue, Apr 16, 2024, at 13:01, Arnd Bergmann wrote:
> > On Tue, Apr 16, 2024, at 11:32, Naresh Kamboju wrote:
> >> The Powerpc clang builds failed due to following warnings / errors on the
> >> Linux next-20240416 tag.
> >>
> >> Powerpc:
> >>  - tqm8xx_defconfig + clang-17 - Failed
> >>  - allnoconfig + clang-17 - Failed
> >>  - tinyconfig + clang-17 - Failed
> >>
> >> Reported-by: Linux Kernel Functional Testing <lkft at linaro.org>
> >
> > I'm not sure why this showed up now, but there is a series from
> > in progress that will avoid this in the future, as the same
> > issue is present on a couple of other architectures.
> >
> 
> I see now, it was introduced by my patch to turn on -Wextra
> by default. I had tested that patch on all architectures
> with allmodconfig and defconfig, but I did not test any
> powerpc configs with PCI disabled.

I think this warning is clang specific as well...  (Maybe clang was
included in all architectures but I'm not sure).

regards,
dan carpenter