From owner-freebsd-current@FreeBSD.ORG  Thu May 17 16:44:53 2012
Return-Path: <owner-freebsd-current@FreeBSD.ORG>
Delivered-To: freebsd-current@FreeBSD.org
Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52])
	by hub.freebsd.org (Postfix) with ESMTP id 099451065674;
	Thu, 17 May 2012 16:44:53 +0000 (UTC)
	(envelope-from dimitry@andric.com)
Received: from springbank.echomania.com (andric.com
	[IPv6:2001:888:2003:1001:230:48ff:fe51:76b6])
	by mx1.freebsd.org (Postfix) with ESMTP id 762D78FC0A;
	Thu, 17 May 2012 16:44:49 +0000 (UTC)
X-Virus-Scanned: Debian amavisd-new at springbank.echomania.com
Received: from [192.168.1.6] (tensor.andric.com [87.251.56.140])
	(using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits))
	(No client certificate requested)
	by springbank.echomania.com (Postfix) with ESMTPSA id CCD50A7071;
	Thu, 17 May 2012 18:44:26 +0200 (CEST)
Message-ID: <4FB52AF9.1010306@andric.com>
Date: Thu, 17 May 2012 18:44:41 +0200
From: Dimitry Andric <dimitry@andric.com>
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64;
	rv:13.0) Gecko/20120425 Thunderbird/13.0
MIME-Version: 1.0
To: Pedro Giffuni <pfg@FreeBSD.org>
References: <4FB51CDF.3040306@FreeBSD.org>
In-Reply-To: <4FB51CDF.3040306@FreeBSD.org>
X-Enigmail-Version: 1.5a1pre
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Cc: freebsd-current@FreeBSD.org, freebsd-toolchain@FreeBSD.org
Subject: Re: GCC update for testing
X-BeenThere: freebsd-current@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Discussions about the use of FreeBSD-current
	<freebsd-current.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>, 
	<mailto:freebsd-current-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-current>
List-Post: <mailto:freebsd-current@freebsd.org>
List-Help: <mailto:freebsd-current-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>,
	<mailto:freebsd-current-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 17 May 2012 16:44:53 -0000

On 2012-05-17 17:44, Pedro Giffuni wrote:> Hi;
> I took a bunch of patches that were merged into the GCC 4.1 branch
> (under GPLv2) and prepared a patch for merging them into our base
> gcc. These are supposed to be bug fixes only.
> 
> You can get the patch here:
> http://people.freebsd.org/~pfg/patches/patch-contrib-gcc
> And, for those really interested, the log is here:
> http://people.freebsd.org/~pfg/patches/gcc41-pr-log
> 
> It may be my imagination but the patch seems to be causing more
> warnings than usual and it breaks the kernel here:
...
> ../../../cam/scsi/scsi_sa.c: In function 'samount':
> ../../../cam/scsi/scsi_sa.c:1887: warning: 'comp_supported' may be used 
> uninitialized in this function
> ../../../cam/scsi/scsi_sa.c:1888: warning: 'write_protect' may be used 
> uninitialized in this function

These warnings seem wrong, upon casual inspection of the code.  In any
case, if you compile the same file with gcc 4.7, they don't appear. :)

Any idea which particular gcc fix is responsible for them?

As a workaround, we could set all those variable to some reasonable
value, but that feels like a cheap trick to me...

But I'd rather just not import the fix that causes those warnings.