From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from [140.186.70.92] (port=48289 helo=eggs.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.43) id 1P5KKq-0006BV-Qe
	for qemu-devel@nongnu.org; Mon, 11 Oct 2010 11:30:49 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <armbru@redhat.com>) id 1P5JlG-0006nu-0l
	for qemu-devel@nongnu.org; Mon, 11 Oct 2010 10:53:59 -0400
Received: from mx1.redhat.com ([209.132.183.28]:51828)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <armbru@redhat.com>) id 1P5JlF-0006mm-QI
	for qemu-devel@nongnu.org; Mon, 11 Oct 2010 10:53:57 -0400
From: Markus Armbruster <armbru@redhat.com>
Subject: Re: [Qemu-devel] [PATCH 03/12] eepro100: initialize a variable in all
	cases
References: <AANLkTim-7Pj=S+pCDD-knA=usWoCWZjVxZBm9ughfVYZ@mail.gmail.com>
Date: Mon, 11 Oct 2010 16:53:54 +0200
In-Reply-To: <AANLkTim-7Pj=S+pCDD-knA=usWoCWZjVxZBm9ughfVYZ@mail.gmail.com>
	(Blue Swirl's message of "Fri, 8 Oct 2010 21:23:44 +0000")
Message-ID: <m3ocb093wd.fsf@blackfin.pond.sub.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
List-Id: qemu-devel.nongnu.org
List-Unsubscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Blue Swirl <blauwirbel@gmail.com>
Cc: qemu-devel <qemu-devel@nongnu.org>

Blue Swirl <blauwirbel@gmail.com> writes:

> Compiling with GCC 4.6.0 20100925 produced warnings:
> /src/qemu/hw/eepro100.c: In function 'eepro100_read4':
> /src/qemu/hw/eepro100.c:1351:14: error: 'val' may be used
> uninitialized in this function [-Werror=uninitialized]
> /src/qemu/hw/eepro100.c: In function 'eepro100_read2':
> /src/qemu/hw/eepro100.c:1328:14: error: 'val' may be used
> uninitialized in this function [-Werror=uninitialized]
> /src/qemu/hw/eepro100.c: In function 'eepro100_read1':
> /src/qemu/hw/eepro100.c:1285:13: error: 'val' may be used
> uninitialized in this function [-Werror=uninitialized]
>
> Fix by initializing 'val' at start.

I don't like sweeping bugs under the carpet like that.  The initial
value is used when and only when the emulation is buggy.  We doubt it
can happen.  If we truly believe it can't happen, assert it.  If we just
doubt it, log it.