X-Recipient: archive-cygwin AT delorie DOT com
X-Spam-Check-By: sourceware.org
Message-ID: <48400A02.EBAEAE13@dessent.net>
Date: Fri, 30 May 2008 07:06:58 -0700
From: Brian Dessent <brian AT dessent DOT net>
X-Mailer: Mozilla 4.79 [en] (Windows NT 5.0; U)
MIME-Version: 1.0
To: Mike Marchywka <marchywka AT hotmail DOT com>
CC: cygwin AT cygwin DOT com
Subject: Re: MS or cygwin dll debug tools/ was  "sys/sockio.h" etc.
References: <17275355 DOT post AT talk DOT nabble DOT com> <17290164 DOT post AT talk DOT nabble DOT com>       <4830F08D DOT 6040505 AT cygwin DOT com> <17345729 DOT post AT talk DOT nabble DOT com>       <4833813A DOT 7B6F7FAF AT dessent DOT net> <17405074 DOT post AT talk DOT nabble DOT com>       <483583EE DOT 8030605 AT cygwin DOT com>     <BLU113-W4491CD4A8C42B16C2A9FB9BEC60 AT phx DOT gbl>       <00e501c8bc1e$a44d0190$2708a8c0 AT CAM DOT ARTIMI DOT COM>       <BLU113-W102F782BB5AAB04B62F71BBEC60 AT phx DOT gbl>       <20080523000735 DOT GA23793 AT ednor DOT casa DOT cgf DOT cx>      <BLU113-W20BC0AE5970EA19F944347BEC20 AT phx DOT gbl>     <483BBE3D DOT EDF663D3 AT dessent DOT net>    <BLU113-W146D9A038F045D262DEF5CBEBD0 AT phx DOT gbl>    <BLU113-W34F5DCFDEEB319379AAAD4BEBC0 AT phx DOT gbl>    <483D7849 DOT 5010505 AT sbcglobal DOT net> <483D7C01 DOT EAE5ADA1 AT dessent DOT net>   <BLU113-W49565CFCD21C93AC4B35C5BEBC0 AT phx DOT gbl>  <483DB6E0 DOT 53C6EED0 AT dessent DOT net> <BLU113-W2449DB0BF1E75F2E2CBB3FBEBC0 AT phx DOT gbl>  <483DC9CF DOT BDAF5D3B AT dessent DOT net> <BLU113-W25EFA6F85DD6EF9EAE290BEBF0 AT phx DOT gbl>
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
X-IsSubscribed: yes
Reply-To: cygwin AT cygwin DOT com
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

Mike Marchywka wrote:
> 
> > .rdata relocs it is then.
> 
> This is why I lurk as I now remember something about this and, sure, I can find it on google.
> Of course, it would still be nice to have a fully instrumented load ( so where do I find the
> unreolcatable data?) .
> I relinked with -strip and used dumpbin to find all the symbols in rdata but there are several hundred.
> I thought I could grep the code for suspicious consts but no luck so far.

The simplest method is just to tweak the linker script to make .rdata
writable (or rather, to map both .data and .rdata input segments into
the same .data output section.)

There is no method that I'm aware of to find the name of the offending
symbol.  Actually, that's not quite true, see
<http://cygwin.com/ml/cygwin-patches/2008-q1/msg00067.html>.  As I said
in that message though, those might just be coindicental and certainly
not guaranteed across OS versions or whatever.

> Isn't there some way to find the offending relocation attempt? What does strace know
> about the stituation or does it just echo stuff from Windoze?

strace under Cygwin is not like strace on other operating systems, it is
really just a glorified viewer for a bunch of debug_printf statements
that exist in the Cygwin code.  The error occurs before the process even
begins execution, during the period where NTLDR loads libraries into its
address space.  So, strace will be of no use.

Brian

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