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From:   Kees Cook <keescook@chromium.org>
Date:   Mon, 12 Feb 2018 08:56:31 -0800
Message-ID: <CAGXu5jLdH7wkrnB9YnRLf+vQsQyfHehUywkXqsBuy6WmVLH3OA@mail.gmail.com>
Subject: Re: [RFC PATCH 4/7] kconfig: support new special property shell=
To:     David Woodhouse <dwmw2@infradead.org>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Ulf Magnusson <ulfalizer@gmail.com>,
        Masahiro Yamada <yamada.masahiro@socionext.com>,
        Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Nicolas Pitre <nicolas.pitre@linaro.org>,
        "Luis R . Rodriguez" <mcgrof@suse.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        Sam Ravnborg <sam@ravnborg.org>,
        Michal Marek <michal.lkml@markovi.net>,
        Martin Schwidefsky <schwidefsky@de.ibm.com>,
        Pavel Machek <pavel@ucw.cz>,
        linux-s390 <linux-s390@vger.kernel.org>,
        Jiri Kosina <jkosina@suse.cz>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Tejun Heo <tj@kernel.org>, Ingo Molnar <mingo@kernel.org>,
        "Van De Ven, Arjan" <arjan.van.de.ven@intel.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Thomas Gleixner <tglx@linutronix.de>
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On Mon, Feb 12, 2018 at 8:19 AM, David Woodhouse <dwmw2@infradead.org> wrote:
> On Mon, 2018-02-12 at 09:26 +0100, Peter Zijlstra wrote:
>> On Sun, Feb 11, 2018 at 10:13:44AM -0800, Linus Torvalds wrote:
>>
>> > That actually sounds like we could just
>> >
>> >  (a) make gcc 4.5 be the minimum required version
>> >
>> >  (b) actually error out if we find a bad compiler
>>
>> So the unofficial plan was to enforce asm-goto and -fentry support by
>> hard failure to build, which would get us at gcc-4.6 and then remove all
>> the fallback cruft needed for those features -- for x86. If we want to
>> do this tree wide, that's obviously OK with me too ;-)
>
> This would also kill clang support, right?

That would be bad: Android exclusively builds with clang.

-Kees

-- 
Kees Cook
Pixel Security