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Date: Tue, 22 Dec 2009 11:33:00 -0000
From: Paolo Bonzini <bonzini@gnu.org>
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To: Richard Guenther <richard.guenther@gmail.com>
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Subject: Re: [PATCH] ARM: Convert BUG() to use unreachable()
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On 12/17/2009 06:17 PM, Richard Guenther wrote:
> It shouldn't as *(int *)0 = 0; might trap.  But if you want to be sure
> use
>     __builtin_trap ();
> instead for the whole sequence (the unreachable is implied then).
> GCC choses a size-optimal trap representation for your target then.

Agree that it shouldn't but just to be sure I'd use

   *(volatile int *)0 = 0;
   unreachable ();

Paolo