Re: drivers/gpu/drm/kmb/kmb_dsi.c:812:2: warning: unused function 'set_test_mode_src_osc_freq_target_low_bits'

From: Geert Uytterhoeven
Date: Tue Sep 28 2021 - 14:10:01 EST


Hi Nathan,

On Tue, Sep 28, 2021 at 6:43 PM Nathan Chancellor <nathan@xxxxxxxxxx> wrote:
> On Tue, Sep 28, 2021 at 05:39:19PM +0200, Geert Uytterhoeven wrote:
> > On Tue, Sep 28, 2021 at 5:09 PM kernel test robot <lkp@xxxxxxxxx> wrote:
> > > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> > > head: 0513e464f9007b70b96740271a948ca5ab6e7dd7
> > > commit: ade896460e4a62f5e4a892a98d254937f6f5b64c drm: DRM_KMB_DISPLAY should depend on ARCH_KEEMBAY
> > > date: 11 months ago
> > > config: mips-randconfig-r013-20210928 (attached as .config)
> > > compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project dc6e8dfdfe7efecfda318d43a06fae18b40eb498)
> > > 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 mips cross compiling tool for clang build
> > > # apt-get install binutils-mips-linux-gnu
> > > # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ade896460e4a62f5e4a892a98d254937f6f5b64c
> > > git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> > > git fetch --no-tags linus master
> > > git checkout ade896460e4a62f5e4a892a98d254937f6f5b64c
> > > # save the attached .config to linux build tree
> > > mkdir build_dir
> > > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=mips SHELL=/bin/bash drivers/gpu/drm/kmb/ drivers/net/ethernet/mellanox/mlxsw/ mm/
> > >
> > > If you fix the issue, kindly add following tag as appropriate
> > > Reported-by: kernel test robot <lkp@xxxxxxxxx>
> > >
> > > All warnings (new ones prefixed by >>):
> > >
> > > >> drivers/gpu/drm/kmb/kmb_dsi.c:812:2: warning: unused function 'set_test_mode_src_osc_freq_target_low_bits'
> > > set_test_mode_src_osc_freq_target_low_bits(struct kmb_dsi
> > > ^
> > > >> drivers/gpu/drm/kmb/kmb_dsi.c:824:2: warning: unused function 'set_test_mode_src_osc_freq_target_hi_bits'
> > > set_test_mode_src_osc_freq_target_hi_bits(struct kmb_dsi
> >
> > These two functions are "static inline", so there should not be such
> > warning. Toolchain issue?
>
> No toolchain issue, Masahiro specifically made clang W=1 builds warns on
> static inline unused functions because of instances like this, see
> commit 6863f5643dd7 ("kbuild: allow Clang to find unused static inline
> functions for W=1 build").

IC, I wasn't aware of that work.

Anyway, the "first bad commit" is the commit introducing the code, not
my commit enabling compile-testing (nor Yamada-san's commit to warn
about it ;-).

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds