Re: sound/soc/meson/t9015.c:315:34: warning: unused variable 't9015_ids'

From: Jerome Brunet
Date: Wed Jun 10 2020 - 11:31:10 EST



On Sun 31 May 2020 at 05:00, kbuild test robot <lkp@xxxxxxxxx> wrote:

> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: ffeb595d84811dde16a28b33d8a7cf26d51d51b3
> commit: 33901f5b9b16d212ee58865e9e8e80fc813f12da ASoC: meson: add t9015 internal DAC driver
> date: 3 months ago
> config: x86_64-randconfig-r033-20200531 (attached as .config)
> compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 2388a096e7865c043e83ece4e26654bd3d1a20d5)
> reproduce (this is a W=1 build):
> wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> chmod +x ~/bin/make.cross
> # install x86_64 cross compiling tool for clang build
> # apt-get install binutils-x86-64-linux-gnu
> git checkout 33901f5b9b16d212ee58865e9e8e80fc813f12da
> # save the attached .config to linux build tree
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kbuild test robot <lkp@xxxxxxxxx>
>
> All warnings (new ones prefixed by >>, old ones prefixed by <<):
>
>>> sound/soc/meson/t9015.c:315:34: warning: unused variable 't9015_ids' [-Wunused-const-variable]
> static const struct of_device_id t9015_ids[] = {
> ^
> 1 warning generated.
>
> vim +/t9015_ids +315 sound/soc/meson/t9015.c
>
> 314
> > 315 static const struct of_device_id t9015_ids[] = {
> 316 { .compatible = "amlogic,t9015", },
> 317 { }
> 318 };
> 319 MODULE_DEVICE_TABLE(of, t9015_ids);
> 320

Hi,

I'm not sure what to do with this report.
I tried to reproduce has instructed, the log is full of warnings and the
compilation eventually fails to link.

It seems that most (if not all) drivers with a MODULE_DEVICE_TABLE() show
this warning with the provided .config (COMPILE_TEST).

When compiled with gcc, no such warning is shown.
I can remove COMPILE_TEST for this driver, it will make the warning go
away but I'm not sure it is appropriate.

>
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx