bug#5802: emacsclient -c crashes emacs --daemon intermittently; have strace

[Dan Nicolaescu <dann@ics.uci.edu>]

Ryan Thompson <rct@thompsonclan.org> writes:

  > On Thu, Apr 1, 2010 at 12:50 PM, Dan Nicolaescu <dann@gnu.org> wrote:
  > > Ryan Thompson <rct@thompsonclan.org> writes:
  > >
  > >> On Tue, Mar 30, 2010 at 10:47 AM, Dan Nicolaescu <dann@gnu.org> wrote:
  > >>> Ryan Thompson <rct@thompsonclan.org> writes:
  > >>>
  > >>>> On Tue, Mar 30, 2010 at 8:46 AM, Dan Nicolaescu <dann@gnu.org> wrote:
  > >>>>> Ryan Thompson <rct@thompsonclan.org> writes:
  > >>>>>
  > >>>>>> I am trying to set myself up using emacs --daemon so that I can easily
  > >>>>>> manage multiple emacs frames within one process. However, I have hit a
  > >>>>>> significant stumbling block. If I run emacs --daemon (or emacs -nw and
  > >>>>>> then do (server-start) ) and then repeatedly run emacsclient -c and
  > >>>>>> clost the resulting window, emacs will randomly crash. Sometimes it
  > >>>>>> happens on the first time that I run emacsclient -c, sometimes on the
  > >>>>>> 20th.
  > >>>>>>
  > >>>>>> I use Ubuntu 9.10, and I have reported this bug in Launchpad. However,
  > >>>>>> I have also compiled both emacs 23.1 and trunk from vanilla sources,
  > >>>>>> and both of these exhibit the same bug as the Ubuntu-packaged
  > >>>>>> versions.
  > >>>>>>
  > >>>>>> I have generated some stack traces by the following procedure, as
  > >>>>>> described at https://bugs.launchpad.net/ubuntu/+source/emacs23/+bug/543611
  > >>>>>>
  > >>>>>> Open two terminals. In the first terminal, run the following commands
  > >>>>>> to start emacs with strace:
  > >>>>>>
  > >>>>>> $ mkdir -p /tmp/emacs-strace
  > >>>>>> $ strace -o /tmp/emacs-strace/trace-`date +%s`.log emacs -Q -nw
  > >>>>>>
  > >>>>>> When emacs has started, do M-x server-start so that emacsclient can
  > >>>>>> work. Now, in the second terminal, run the following command:
  > >>>>>>
  > >>>>>> $ x=0; while emacsclient -c ; do x=$(( $x + 1 )); done; echo "Created
  > >>>>>> $x windows before crash."
  > >>>>>>
  > >>>>>> Now, an emacs window will open. Close it. Each time you close a
  > >>>>>> window, a new emacs window will open. Keep closing each one that
  > >>>>>> appears. If emacs exhibits the bug, then eventually you will close one
  > >>>>>> window, and emacs will crash when it tries to create the next one. At
  > >>>>>> this point, you can go get your stack trace in /tmp/emacs-strace.
  > >>>>>
  > >>>>> This is very likely due to a long standing bug in Gtk+, see:
  > >>>>> http://bugzilla.gnome.org/show_bug.cgi?id=85715
  > >>>>>
  > >>>>> Please compile emacs using
  > >>>>>
  > >>>>> ./configure --with-x-toolkit=lucid
  > >>>>>
  > >>>>> and try to reproduce the problem you are seeing with that emacs.
  > >>>>>
  > >>>>
  > >>>> I tried that; same problem. Would you like a stack trace?
  > >>>
  > >>> Sure, for the lucid version please.
  > >>> But please get the stack trace using by attaching gdb to emacs.
  > >>> See etc/DEBUG for more info.
  > >>>
  > >>> Also, please start emacs using "emacs -Q"
  > >>>
  > >>>
  > >>>
  > >>
  > >> I tried to figure out gdb, but I couldn't figure it out in the time I
  > >> had. But I have been running all my tests with -Q. I'll try again when
  > >> I have more time to mess around with it.
  > >
  > > cd emacs/src
  > > gdb ./emacs
  > > run -Q -nw -f server-start
  > >
  > >
  > > do whatever you do to to crash emacs, and when that happens type
  > >
  > > xbacktrace
  > >
  > > in gdb
  > >
  > > Again, this is only useful for the version compiled using ./configure --with-x-toolkit=lucid
  > >
  > 
  > On further inspection, I can no longer reproduce the crash
  > --with-x-toolkit=lucid. The segfault in the gtk version occurs in
  > "gdk_screen_get_display," from /usr/lib/libgdk-x11-2.0.so.0, which is
  > in Ubuntu package libgtk2.0-0 version 2.18.3-1ubuntu2.2.
  > 
  > When the lucid version, emacs does not crash, but for some reason,
  > when I run the emacsclient frame-creating loop that I described
  > previously, sometimes the client frame disappears as soon as it
  > appears, and I assumed that a crash had occurred. But in this case,
  > emacs does not crash, and I only get the problem in a loop like this.
  > Simply running "emacsclient -c" manually over and over at the
  > command-line never causes a frame to disappear. So, I think I will
  > move forward using the lucid version, and you can mark this as a GTK
  > problem.
  > 
  > Thanks for your patience.

Closing this the, we have plenty of similar reports.