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Date: Mon, 10 Nov 2008 15:58:08 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: kosaki.motohiro@jp.fujitsu.com, linux-serial@vger.kernel.org,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH] serial/8250: fix uninitialized warnings
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On Mon, 10 Nov 2008 23:48:43 +0000
Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:

> > That's a regression in current gcc, surely?
> 
> Oh and as a PS: Gcc is I believe right because if the loop is run zero
> times then pos = NULL (ie n == NULL so the first BUG_ON fires)

Whoa.  That would be clever of it.


On about half the architectures, BUG is not considered to be no-return.
Dunno if that's a gcc shortcoming or if the architectures just haven't
implemented it properly yet.  This causes those architectures to
generate quite a few warnings in generic code which don't appear on
x86 (this would be one such case if your above theory is correct).

This is fairly irritating of those architectures, as I keep on going
in asking "what's up" and deciding "oh, that again".