From mboxrd@z Thu Jan  1 00:00:00 1970
From: linux@arm.linux.org.uk (Russell King - ARM Linux)
Date: Mon, 21 Dec 2009 20:10:59 +0000
Subject: [PATCH] ARM: Convert BUG() to use unreachable()
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	<20091217181718.GA4440@n2100.arm.linux.org.uk>
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Message-ID: <20091221201059.GD11669@n2100.arm.linux.org.uk>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Mon, Dec 21, 2009 at 11:30:43AM -0800, Richard Henderson wrote:
> On 12/17/2009 10:17 AM, Russell King - ARM Linux wrote:
>> How is "size-optimal trap" defined?
>
> E.g. Sparc and MIPS have "tcc" instructions that trap based on the
> condition codes, and so we eliminate the branch.  That's the only
> optimization we apply with __builtin_trap.
>
>> Let me put it another way: I want this function to terminate with an
>> explicit NULL pointer dereference in every case.
>
> Then just use that.

That's precisely what we have been using for many years.