From: Michael Enright <mike@kmcardiff.com>
To: cygwin@cygwin.com
Subject: Re: Analyzing a SEG FAULT that gdb doesn't help with
Date: Thu, 30 Jul 2015 17:46:00 -0000 [thread overview]
Message-ID: <CAOC2fq-ET7BmUQYOLXV_w_QMZE1rfZ8_JpJvVGF=nDS7gTaWWA@mail.gmail.com> (raw)
In-Reply-To: <55BA373A.4020909@dronecode.org.uk>
On Thu, Jul 30, 2015 at 7:39 AM, Jon TURNEY wrote:
> You need to install the 'cygwin-debuginfo' package for debug symbols for
> cygwin1.dll
I missed this in my searches. I see now that I should have used the
"debug" category.
>
> You also need to point addr2line at those detached debug symbols, as (unlike
> gdb) it doesn't follow .gnu_debuglink pointers.
>
> (I'm assuming you've typoed 6155d363 here and it should be 0x6115D363 as the
> strace output says)
I've been having trouble getting that number right
>
> # addr2line -e /usr/lib/debug/usr/bin/cygwin1.dbg 0x6115D363
> /usr/src/debug/cygwin-2.1.0-1/newlib/libc/machine/i386/strlen.S:64
Another problem is that there's only one stack frame in the stack
dump, so knowing that it's a strlen just means I have to crank out
some grep commands and hopefully one of them is vulnerable to a
special case that now happens all the time.
>
> Are you sure the crashing process is the direct
> inferior of gdb, and not some wrapper process which runs it? (uninstalled
> libtool generated binaries do this, for e.g.)
>
The crashing executable is just a client of SpiderMonkey (via
libmozjs185) with several extensions to JavaScript in order to emulate
some of the Windows cscript utility and to emulate another environment
that happens to be a massive annoyance to run scripts in. The
executable is built using a textbook Makefile.
--
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
next prev parent reply other threads:[~2015-07-30 17:46 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-29 23:16 Michael Enright
2015-07-30 14:40 ` Jon TURNEY
2015-07-30 17:46 ` Michael Enright [this message]
2015-07-30 18:48 ` Michael Enright
2015-07-31 12:51 ` Jon TURNEY
2015-07-31 18:46 ` Michael Enright
2015-07-31 20:12 ` Michael Enright
2015-08-01 20:28 ` Brian Inglis
2015-08-02 1:55 ` Michael Enright
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='CAOC2fq-ET7BmUQYOLXV_w_QMZE1rfZ8_JpJvVGF=nDS7gTaWWA@mail.gmail.com' \
--to=mike@kmcardiff.com \
--cc=cygwin@cygwin.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).