2022-11-10 12:22:51

by Naresh Kamboju

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

[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 <[email protected]>

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.

tuxmake --runtime podman --target-arch x86_64 --toolchain
clang-nightly --kconfig defconfig --kconfig-add
https://raw.githubusercontent.com/Linaro/meta-lkft/kirkstone/meta/recipes-kernel/linux/files/lkft.config
--kconfig-add https://raw.githubusercontent.com/Linaro/meta-lkft/kirkstone/meta/recipes-kernel/linux/files/lkft-crypto.config
--kconfig-add https://raw.githubusercontent.com/Linaro/meta-lkft/kirkstone/meta/recipes-kernel/linux/files/distro-overrides.config
--kconfig-add https://raw.githubusercontent.com/Linaro/meta-lkft/kirkstone/meta/recipes-kernel/linux/files/systemd.config
--kconfig-add https://raw.githubusercontent.com/Linaro/meta-lkft/kirkstone/meta/recipes-kernel/linux/files/virtio.config
--kconfig-add CONFIG_IGB=y --kconfig-add
CONFIG_UNWINDER_FRAME_POINTER=y LLVM=1 LLVM_IAS=1



Build log:
[1] https://builds.tuxbuild.com/2HLg3VgMgxRXBn31n6Ig7BFwSy9/


--
Linaro LKFT
https://lkft.linaro.org


2022-11-10 13:01:32

by Nathan Chancellor

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

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 <[email protected]>
>
> 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/[email protected]/
https://github.com/ClangBuiltLinux/linux/issues/1757

It just needs to be reviewed and picked up.

Cheers,
Nathan