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References: <20190126071122.24557-1-natechancellor@gmail.com>
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From:   Nick Desaulniers <ndesaulniers@google.com>
Date:   Fri, 25 Jan 2019 23:34:19 -0800
Message-ID: <CAKwvOdmA6075WEPaKkL9d1wUQmboU9CxhbNT1oiVk8_Onjh5Rg@mail.gmail.com>
Subject: Re: [PATCH v2] drm/i915: Disable -Wuninitialized
To:     Nathan Chancellor <natechancellor@gmail.com>
Cc:     Jani Nikula <jani.nikula@linux.intel.com>,
        Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@intel.com>,
        intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
        LKML <linux-kernel@vger.kernel.org>,
        Chris Wilson <chris@chris-wilson.co.uk>,
        Matthias Kaehlcke <mka@chromium.org>
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On Fri, Jan 25, 2019 at 11:13 PM Nathan Chancellor
<natechancellor@gmail.com> wrote:
>
> This warning is disabled by default in scripts/Makefile.extrawarn when
> W= is not provided but this Makefile adds -Wall after this warning is
> disabled so it shows up in the build when it shouldn't:
>
> In file included from drivers/gpu/drm/i915/intel_breadcrumbs.c:895:
> drivers/gpu/drm/i915/selftests/intel_breadcrumbs.c:350:34: error:
> variable 'wq' is uninitialized when used within its own initialization
> [-Werror,-Wuninitialized]
>         DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
>                                         ^~
> ./include/linux/wait.h:74:63: note: expanded from macro
> 'DECLARE_WAIT_QUEUE_HEAD_ONSTACK'
>         struct wait_queue_head name = __WAIT_QUEUE_HEAD_INIT_ONSTACK(name)
>                                ~~~~                                  ^~~~
> ./include/linux/wait.h:72:33: note: expanded from macro
> '__WAIT_QUEUE_HEAD_INIT_ONSTACK'
>         ({ init_waitqueue_head(&name); name; })
>                                        ^~~~
> 1 error generated.
>
> Explicitly disable the warning like commit 46e2068081e9 ("drm/i915:
> Disable some extra clang warnings").
>
> Link: https://github.com/ClangBuiltLinux/linux/issues/220
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

Reviewed-by: Nick Desaulniers <nick.desaulniers@gmail.com>

probably could give Chris Wilson the suggested by tag.
https://lore.kernel.org/lkml/154513398652.1108.7150969916024071452@skylake-alporthouse-com/

> ---
>
> v1 -> v2:
>
> * Rather than disable the warning for the problematic folder, disable it
>   for the entire folder like Matthias's commit.

Thanks for following up with a v2.

-- 
Thanks,
~Nick Desaulniers