bug#12579: 24.1; Emacs 24.1 / 24.2 (daily) crashes

[Eli Zaretskii <eliz@gnu.org>]

> From: "Fabrice Niessen" <fni@missioncriticalit.com>
> Cc: thierry.volpiatto@gmail.com,  drew.adams@oracle.com,  lekktu@gmail.com,  12579@debbugs.gnu.org
> Date: Tue, 06 Nov 2012 10:42:37 +0100
> 
> Hello Eli,
> 
> Eli Zaretskii wrote:
> >> (gdb) thread apply all backtrace
> >
> > This indicates you had 3 network streams that Emacs was reading from.
> > Any idea which connections were those?
> 
> The "only" things I use Emacs for are:
> 
> - editing local files (found on my computer, not on a network share)
> - reading and composing mails with Gnus

Strange.

> However, if process communications are seen as network streams

No, the backtrace clearly shows that we are communicating via Winsock:

  #4  0x719f67de in WSACancelAsyncRequest () from /cygdrive/c/WINDOWS/system32/Ws2_32.dll
  #5  0x0108d925 in _sys_read_ahead (fd=8) at w32.c:6079
  #6  0x01033127 in reader_thread (arg=0x167dda0) at w32proc.c:838

See that call to WSACancelAsyncRequest?

> > Next time, please type "xbacktrace" and show the Lisp backtrace it
> > produces.  (You will need the .gdbinit file from the source
> > repository, and you will need to type "source .gdbinit" before
> > invoking "xbacktrace".)
> 
> I just downloaded the .gdbinit found in
> http://ftp.gnu.org/gnu/emacs/emacs-24.2.tar.xz (from... 27-Aug-2012), as I
> just had a similar problem (infloop when filling Helm-for-files pattern).
> 
>   QUESTION -- Is it therein I'm supposed to fetch the .gdbinit from?

You need to get it from the same source distribution as the one used
for building Emacs.  If you are using v24.2 (not 24.2.50 or some
such), then the above is indeed the right .gdbinit.

> However, it does not seem that I can do that as easily: this ain't compatible
> with the GNU Emacs 24.2.50.1 (i386-mingw-nt5.1.2600) of 2012-10-22 on DANI-PC.

I don't expect it to be: 24.2.50 is a development snapshot, and a lot
was changed in the internal data structures since 24.2 was released.

> But I had to take a recently compiled Emacs from
> https://www.dropbox.com/sh/7jr3vbv9tm1zod0/jPuvfrJAe8 (to be exact, the
> version emacs-trunk-r110618-w32-i386.zip, on 22-Oct-2012), as there is no new
> official version of Emacs for Windows since a while...

Then you can get a matching .gdbinit from the bzr repository here:

  http://bzr.savannah.gnu.org/lh/emacs/trunk/annotate/head:/src/.gdbinit

> >> I don't understand the 2 screen processes (I just see 1), but that must
> >> explain the 2 zsh processes...
> >
> > I don't understand even the single screen.exe: what does that do?
> 
> GNU screen is a terminal multiplexer

I know what GNU screen is, I just didn't expect to see it on a Windows
machine that uses a native Windows build of Emacs.  Is screen.exe a
Cygwin build of screen?  Are you using it to run several versions of
Emacs?