Re: [linux-next:master 1323/3381] drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c:333:4: error: format specifies type 'unsigned char' but the argument has type 'int'

[Nick Desaulniers <ndesaulniers@google.com>]

On Tue, Jun 4, 2024 at 11:17 PM Nathan Chancellor <nathan@kernel.org> wrote:
>
> On Wed, Jun 05, 2024 at 06:23:57AM +0800, kernel test robot wrote:
> > tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
> > head:   d97496ca23a2d4ee80b7302849404859d9058bcd
> > commit: 0ea55445554209913a72eab86b60f5788776c4d6 [1323/3381] drm/amdgpu: Fix snprintf usage in amdgpu_gfx_kiq_init_ring
> > config: arm64-randconfig-003-20240605 (https://download.01.org/0day-ci/archive/20240605/202406050622.SmOX6DL6-lkp@intel.com/config)
> > compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
> > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240605/202406050622.SmOX6DL6-lkp@intel.com/reproduce)
> >
> > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > the same patch/commit), kindly add following tags
> > | Reported-by: kernel test robot <lkp@intel.com>
> > | Closes: https://lore.kernel.org/oe-kbuild-all/202406050622.SmOX6DL6-lkp@intel.com/
> >
> > All errors (new ones prefixed by >>):
> >
> > >> drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c:333:4: error: format specifies type 'unsigned char' but the argument has type 'int' [-Werror,-Wformat]
> >                     xcc_id, ring->me, ring->pipe, ring->queue);
> >                     ^~~~~~
> > >> drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c:333:12: error: format specifies type 'unsigned char' but the argument has type 'u32' (aka 'unsigned int') [-Werror,-Wformat]
> >                     xcc_id, ring->me, ring->pipe, ring->queue);
> >                             ^~~~~~~~
> >    drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c:333:22: error: format specifies type 'unsigned char' but the argument has type 'u32' (aka 'unsigned int') [-Werror,-Wformat]
> >                     xcc_id, ring->me, ring->pipe, ring->queue);
> >                                       ^~~~~~~~~~
> >    drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c:333:34: error: format specifies type 'unsigned char' but the argument has type 'u32' (aka 'unsigned int') [-Werror,-Wformat]
> >                     xcc_id, ring->me, ring->pipe, ring->queue);
> >                                                   ^~~~~~~~~~~
> >    4 errors generated.
>
> For what it's worth, I think that we take care not to enable -Wformat
> with clang versions older than 16 because of this issue, see commit
> b0839b281c42 ("Makefile.extrawarn: re-enable -Wformat for clang; take
> 2") for more information. However, now that I am looking at
> scripts/Makefile.extrawarn, it appears that we only do that for a normal
> build, not W=1? That seems like a potential oversight of that change but
> I am a little fuzzy on the conversation around that and I am not sure
> Nick is around to answer that...

Yeah, unless `-Wformat` was being set explicitly somewhere else when I
wrote b0839b281c42 and has since been removed (-Wformat is part of
-Wall), then it looks like my "old clang" workarounds is only for "not
W=1 builds."  That block just needs to be moved outside of the
corresponding ifneq's else block.

>
> Cheers,
> Nathan



-- 
Thanks,
~Nick Desaulniers