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

From: Nathan Chancellor <nathan@kernel.org>
To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: kernel test robot <lkp@intel.com>,
	llvm@lists.linux.dev, kbuild-all@lists.01.org,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Daniel Vetter <daniel.vetter@ffwll.ch>
Subject: Re: drivers/gpu/drm/kmb/kmb_dsi.c:812:2: warning: unused function 'set_test_mode_src_osc_freq_target_low_bits'
Date: Tue, 28 Sep 2021 09:43:30 -0700	[thread overview]
Message-ID: <YVNGMg/TI+jo/1R1@archlinux-ax161> (raw)
In-Reply-To: <CAMuHMdX0Zm_hMheZ0e1Xu991jnUr=aY_cDBHHGFvQ1sKqM1b9A@mail.gmail.com>

Hi Geert,

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@intel.com> 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@intel.com>
> >
> > 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").

Cheers,
Nathan