Hi all,
After merging the kspp-gustavo tree, today's linux-next build (arm
multi_v7_defconfig) produced this warning:
/home/sfr/next/next/drivers/gpu/drm/msm/msm_gem.c: In function 'msm_gem_new_impl':
/home/sfr/next/next/drivers/gpu/drm/msm/msm_gem.c:1170:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
1170 | if (priv->has_cached_coherent)
| ^
/home/sfr/next/next/drivers/gpu/drm/msm/msm_gem.c:1173:2: note: here
1173 | default:
| ^~~~~~~
Introduced by commit
d12e339044a0 ("drm/msm: add MSM_BO_CACHED_COHERENT")
Presumably exposed by commit
73ffc61f4a8b ("Makefile: Enable -Wimplicit-fallthrough for Clang")
though I am not sure why since I am building with gcc. The first
commit above introduces a new use of /* fallthrough */
--
Cheers,
Stephen Rothwell
Hi Stephen,
On 7/12/21 19:22, Stephen Rothwell wrote:
> Hi all,
>
> After merging the kspp-gustavo tree, today's linux-next build (arm
> multi_v7_defconfig) produced this warning:
>
> /home/sfr/next/next/drivers/gpu/drm/msm/msm_gem.c: In function 'msm_gem_new_impl':
> /home/sfr/next/next/drivers/gpu/drm/msm/msm_gem.c:1170:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
> 1170 | if (priv->has_cached_coherent)
> | ^
> /home/sfr/next/next/drivers/gpu/drm/msm/msm_gem.c:1173:2: note: here
> 1173 | default:
> | ^~~~~~~
>
> Introduced by commit
>
> d12e339044a0 ("drm/msm: add MSM_BO_CACHED_COHERENT")
>
> Presumably exposed by commit
>
> 73ffc61f4a8b ("Makefile: Enable -Wimplicit-fallthrough for Clang")
>
> though I am not sure why since I am building with gcc. The first
> commit above introduces a new use of /* fallthrough */
We have previously adopted the new pseudo-keyword macro fallthrough; So,
we want to avoid having more /* fallthrough */ comments being introduced.
This is also being enforced by commit
73ffc61f4a8b ("Makefile: Enable -Wimplicit-fallthrough for Clang")
for both GCC and Clang.
So, the fix for this issue is merely to replace the /* fallthrough */ comment
with fallthrough;
Thanks
--
Gustavo
Stephen
On 7/12/21 20:10, Gustavo A. R. Silva wrote:
> Hi Stephen,
>
> On 7/12/21 19:22, Stephen Rothwell wrote:
>> Hi all,
>>
>> After merging the kspp-gustavo tree, today's linux-next build (arm
>> multi_v7_defconfig) produced this warning:
>>
>> /home/sfr/next/next/drivers/gpu/drm/msm/msm_gem.c: In function 'msm_gem_new_impl':
>> /home/sfr/next/next/drivers/gpu/drm/msm/msm_gem.c:1170:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
>> 1170 | if (priv->has_cached_coherent)
>> | ^
>> /home/sfr/next/next/drivers/gpu/drm/msm/msm_gem.c:1173:2: note: here
>> 1173 | default:
>> | ^~~~~~~
>>
>> Introduced by commit
>>
>> d12e339044a0 ("drm/msm: add MSM_BO_CACHED_COHERENT")
>>
>> Presumably exposed by commit
>>
>> 73ffc61f4a8b ("Makefile: Enable -Wimplicit-fallthrough for Clang")
>>
>> though I am not sure why since I am building with gcc. The first
>> commit above introduces a new use of /* fallthrough */
>
> We have previously adopted the new pseudo-keyword macro fallthrough; So,
> we want to avoid having more /* fallthrough */ comments being introduced.
> This is also being enforced by commit
>
> 73ffc61f4a8b ("Makefile: Enable -Wimplicit-fallthrough for Clang")
>
> for both GCC and Clang.
>
> So, the fix for this issue is merely to replace the /* fallthrough */ comment
> with fallthrough;
I've already added a fix for this to my -next branch:
https://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux.git/commit/?h=for-next/kspp&id=e181ad43887c6b6b5995e9b191666f04242d77eb
Thanks for the report!
--
Gustavo