Mailing-List: contact cygwin-help AT sourceware DOT cygnus DOT com; run by ezmlm
List-Subscribe: <mailto:cygwin-subscribe AT sources DOT redhat DOT com>
List-Archive: <http://sources.redhat.com/ml/cygwin/>
List-Post: <mailto:cygwin AT sources DOT redhat DOT com>
List-Help: <mailto:cygwin-help AT sources DOT redhat DOT com>, <http://sources.redhat.com/ml/#faqs>
Sender: cygwin-owner AT sources DOT redhat DOT com
Delivered-To: mailing list cygwin AT sources DOT redhat DOT com
From: "Markus Hoenicka" <Markus DOT Hoenicka AT uth DOT tmc DOT edu>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Message-ID: <15007.50216.75000.569222@gargle.gargle.HOWL>
Date: Fri, 2 Mar 2001 16:02:48 +0000 (CT0)
To: cygwin AT cygwin DOT com
Subject: strace question
X-Mailer: VM 6.75 under Emacs 20.6.1

Hi,

I hope this is not a completely dumb question, but here we go.

I'm trying to debug a dynamically linked C++ app that runs just fine
on other platforms including native Win32. As previously reported, the
statically linked version runs fine on Cygwin, whereas the dynamically
linked version creates all expected output, but then dies with a
SIGSEV and causes an error popup ("The instruction at 0xsomething
referenced memory at 0xwhatever. The memory could not be read")
instead of just exiting.

I tried to get a hint from strace as to where the program dies. I ran
both the statically linked and the dynamically linked version and get
exactly the same strace output. There is no such error popup in this
case for the dynamically linked version and no hint in the strace
output that the prog receives a SIGSEV signal.

Does strace magically protect applications from crashing? Is this
expected behaviour? If not, does that tell me anything about what is
wrong with the dynamic linking?

BTW debugging this directly with gdb fails as any attempt to gain
information at the crash point (bt and the like) just show "Cannot
access memory at address 0x2000000".

Any help is appreciated.

Markus

-- 
Markus Hoenicka, PhD
UT Houston Medical School
Dept. of Integrative Biology and Pharmacology
6431 Fannin MSB4.114
Houston, TX 77030
(713) 500-6313, -7477
(713) 500-7444 (fax)
Markus DOT Hoenicka AT uth DOT tmc DOT edu
http://ourworld.compuserve.com/homepages/hoenicka_markus/


--
Want to unsubscribe from this list?
Check out: http://cygwin.com/ml/#unsubscribe-simple