Re: x86: clang: acpi-cpufreq.c:970:24: error: variable 'ret' is uninitialized when used here [-Werror,-Wuninitialized]

From: Nathan Chancellor <nathan@kernel.org>
To: Naresh Kamboju <naresh.kamboju@linaro.org>
Cc: open list <linux-kernel@vger.kernel.org>,
	Linux-Next Mailing List <linux-next@vger.kernel.org>,
	lkft-triage@lists.linaro.org, llvm@lists.linux.dev,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	Viresh Kumar <viresh.kumar@linaro.org>,
	Arnd Bergmann <arnd@arndb.de>,
	Linux PM <linux-pm@vger.kernel.org>
Subject: Re: x86: clang: acpi-cpufreq.c:970:24: error: variable 'ret' is uninitialized when used here [-Werror,-Wuninitialized]
Date: Thu, 10 Nov 2022 05:46:42 -0700	[thread overview]
Message-ID: <Y2zysjBdAERPdUOQ@dev-arch.thelio-3990X> (raw)
In-Reply-To: <CA+G9fYtaNmXOKnwH_ih9vZyFeaD+Lvzxf3WTbAV50rBtwkPxpQ@mail.gmail.com>

Hi Naresh,

On Thu, Nov 10, 2022 at 04:44:09PM +0530, Naresh Kamboju wrote:
> [Please ignore email this if it is already reported]
> 
> Kernel build warning noticed on x86_64 with clang toolchain [1].
> Build failures noticed from next-20221108 .. next-20221110.
> 
> Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
> 
> make --silent --keep-going --jobs=8
> O=/home/tuxbuild/.cache/tuxmake/builds/1/build LLVM=1 LLVM_IAS=1
> ARCH=x86_64 SRCARCH=x86 CROSS_COMPILE=x86_64-linux-gnu- HOSTCC=clang
> CC=clang
> drivers/cpufreq/acpi-cpufreq.c:970:24: error: variable 'ret' is
> uninitialized when used here [-Werror,-Wuninitialized]
>         acpi_cpufreq_online = ret;
>                               ^~~
> drivers/cpufreq/acpi-cpufreq.c:960:9: note: initialize the variable
> 'ret' to silence this warning
>         int ret;
>                ^
>                 = 0
> 1 error generated.

Thanks for the report. I noticed this when it came down in next-20221108
and sent a patch for it:

https://lore.kernel.org/20221108170103.3375832-1-nathan@kernel.org/
https://github.com/ClangBuiltLinux/linux/issues/1757

It just needs to be reviewed and picked up.

Cheers,
Nathan