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Date: Mon, 12 Feb 2018 18:05:10 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Kees Cook <keescook@chromium.org>
Cc: David Woodhouse <dwmw2@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>
Subject: Re: [RFC PATCH 4/7] kconfig: support new special property shell=
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On Mon, Feb 12, 2018 at 08:56:31AM -0800, Kees Cook wrote:
> That would be bad: Android exclusively builds with clang.

So implement asm-goto already, and do asm-cc-output while you're at it.

The whole asm-goto/jump_label stuff really does make a measureable
difference in performance, and its bloody rediculous LLVM doesn't have
it.

And no, a different interface to do something similar is not OK. We're
not going to have a second implementation of jump-labels and everything
else that uses it.