X-Recipient:	archive-cygwin AT delorie DOT com
X-SWARE-Spam-Status:	No, hits=-5.6 required=5.0 tests=AWL,BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,KHOP_RCVD_TRUST,KHOP_THREADED,RCVD_IN_DNSWL_LOW,RCVD_IN_HOSTKARMA_YE,TW_BJ,TW_JC,TW_YG
X-Spam-Check-By:	sourceware.org
X-Received:	by 10.224.179.75 with SMTP id bp11mr10034932qab.22.1358523270285; Fri, 18 Jan 2013 07:34:30 -0800 (PST)
Message-ID:	<50F96B81.8090106@gmail.com>
Date:	Fri, 18 Jan 2013 16:34:25 +0100
From:	marco atzeri <marco DOT atzeri AT gmail DOT com>
User-Agent:	Mozilla/5.0 (Windows NT 6.1; WOW64; rv:17.0) Gecko/20130107 Thunderbird/17.0.2
MIME-Version:	1.0
To:	cygwin AT cygwin DOT com
Subject:	Re: Binutils objcopy bug (was Re: rebase segfault)
References:	<50F516C8 DOT 9050602 AT gmail DOT com> <20130115100745 DOT GC2353 AT calimero DOT vinschen DOT de> <50F5312A DOT 2040503 AT gmail DOT com> <20130115112406 DOT GA13752 AT calimero DOT vinschen DOT de> <50F5D246 DOT 6010902 AT gmail DOT com> <50F653AB DOT 80102 AT gmail DOT com> <20130116123509 DOT GA16991 AT calimero DOT vinschen DOT de>
In-Reply-To:	<20130116123509.GA16991@calimero.vinschen.de>
X-IsSubscribed:	yes
Mailing-List:	contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id:	<cygwin.cygwin.com>
List-Subscribe:	<mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive:	<http://sourceware.org/ml/cygwin/>
List-Post:	<mailto:cygwin AT cygwin DOT com>
List-Help:	<mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender:	cygwin-owner AT cygwin DOT com
Mail-Followup-To:	cygwin AT cygwin DOT com
Delivered-To:	mailing list cygwin AT cygwin DOT com

On 1/16/2013 1:35 PM, Corinna Vinschen wrote:
>
> As far as I can tell it's an objcopy bug.
>
> The stripped version of the DLL has a normal relocation information
> which at one point ends in a NULL IMAGE_BASE_RELOCATION record, as
> expected.  After calling `objcopy --add-gnu-debuglink', the relocation
> information is supposed to be the same as before, since the relocatable
> file content didn't change.
>
> Nevertheless, when stepping through the relocator code in rebase, it
> turns out that the former NULL IMAGE_BASE_RELOCATION record does not
> contain only 0 values anymore.  Rather, it has been overwritten with
> some random(?) non-0 values, which rebase correctly interprets as the
> start of the next IMAGE_BASE_RELOCATION array.  So rebase blunders
> along, thus either just SEGVing, if everything goes well, or, worst
> case, overwriting formerly correct information in the file with
> arbitrary data.
>
> This is a serious bug in objcopy in the current binutils.  Given that
> cygport creates the debug info automatically, we might end up with
> spuriously broken DLLs in the distro.
>
> I checked with objcopy from the older binutils 2.51.53-2, and the
> problem did not show up.  I also built the latest binutils release
> 2.23.1 and the problem also doesn't show, so we probably can get away
> with just a black eye by updating binutils to 2.23.1.  Chris?
>
>
> Corinna
>

Chris,
any news ?

Marco



--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

- Raw text -