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Date: Tue, 16 Apr 2024 15:42:23 +0300
From: Dan Carpenter <dan.carpenter@linaro.org>
To: Arnd Bergmann <arnd@arndb.de>
Cc: Naresh Kamboju <naresh.kamboju@linaro.org>,
	open list <linux-kernel@vger.kernel.org>,
	lkft-triage@lists.linaro.org,
	Linux Regressions <regressions@lists.linux.dev>,
	linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
	"Aneesh Kumar K.V" <aneesh.kumar@kernel.org>,
	Anders Roxell <anders.roxell@linaro.org>,
	Kees Cook <keescook@chromium.org>,
	Niklas Schnelle <schnelle@linux.ibm.com>,
	clang-built-linux <llvm@lists.linux.dev>,
	Nick Desaulniers <ndesaulniers@google.com>,
	Nathan Chancellor <nathan@kernel.org>,
	Jeff Xu <jeffxu@chromium.org>,
	"Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
Subject: Re: powerpc: io-defs.h:43:1: error: performing pointer arithmetic on
 a null pointer has undefined behavior [-Werror,-Wnull-pointer-arithmetic]
Message-ID: <402a5e3b-bdb5-40a4-8a44-2de497849c3f@moroto.mountain>
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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@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