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From:   Nick Desaulniers <ndesaulniers@google.com>
Date:   Fri, 9 Nov 2018 10:08:53 -0800
Message-ID: <CAKwvOdkfGZDWr5vjNTvn707+Muna3JNKObwOfjjvS2-tAXK2QA@mail.gmail.com>
Subject: Re: [PATCH v2 1/2] kbuild: add -no-integrated-as Clang option unconditionally
To:     Masahiro Yamada <yamada.masahiro@socionext.com>
Cc:     Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>,
        Stefan Agner <stefan@agner.ch>,
        Matthias Kaehlcke <mka@chromium.org>, joel@jms.id.au,
        linuxppc-dev@lists.ozlabs.org, mpe@ellerman.id.au,
        Michal Marek <michal.lkml@markovi.net>,
        LKML <linux-kernel@vger.kernel.org>
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On Mon, Nov 5, 2018 at 7:05 PM Masahiro Yamada
<yamada.masahiro@socionext.com> wrote:
>
> We are still a way off the Clang's integrated assembler support for
> the kernel. Hence, -no-integrated-as is mandatory to build the kernel
> with Clang. If you had an ancient version of Clang that does not
> recognize this option, you would not be able to compile the kernel
> anyway.
>
> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
> ---
>
> Changes in v2:
>   - New patch
>
>  Makefile | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/Makefile b/Makefile
> index 93315eb..da11700 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -497,8 +497,8 @@ CLANG_GCC_TC        := --gcc-toolchain=$(GCC_TOOLCHAIN)
>  endif
>  KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) $(CLANG_PREFIX)
>  KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) $(CLANG_PREFIX)
> -KBUILD_CFLAGS += $(call cc-option, -no-integrated-as)
> -KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
> +KBUILD_CFLAGS += -no-integrated-as
> +KBUILD_AFLAGS += -no-integrated-as

Sorry for the delay in review.
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>

>  endif
>
>  RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
> --
> 2.7.4
>


-- 
Thanks,
~Nick Desaulniers