gnome-panel crashes with empty applications.menu

[adammw]

having a blank applications.menu in ~/.config/menus causes gnome-panel to segfault.

I expect this not to happen, for it to fail silently or just with a log note, not crash my entire panel.

Program received signal SIGSEGV, Segmentation fault.
0x00000000004375a1 in create_applications_menu (menu_file=<optimised out>,
    menu_path=0x0, always_show_image=1) at menu.c:1243
1243 menu.c: No such file or directory.
(gdb) bt
#0 0x00000000004375a1 in create_applications_menu (menu_file=<optimised out>,
    menu_path=0x0, always_show_image=1) at menu.c:1243
#1 0x000000000043fbc6 in panel_menu_bar_init (menubar=0x6de200)
    at panel-menu-bar.c:119
#2 0x00007ffff577d957 in g_type_create_instance (type=<optimised out>)
    at /build/buildd/glib2.0-2.32.3/./gobject/gtype.c:1892
#3 0x00007ffff57620b9 in g_object_constructor (type=<optimised out>,
    n_construct_properties=0, construct_params=0x0)
    at /build/buildd/glib2.0-2.32.3/./gobject/gobject.c:1849
#4 0x00007ffff5763c02 in g_object_newv (object_type=10913904, n_parameters=0,
    parameters=0x0) at /build/buildd/glib2.0-2.32.3/./gobject/gobject.c:1632
#5 0x00007ffff57641ec in g_object_new (object_type=10913904,
    first_property_name=0x0)
    at /build/buildd/glib2.0-2.32.3/./gobject/gobject.c:1542
#6 0x000000000043fdb5 in panel_menu_bar_load (panel=0x6e4200,
    id=0xa8e210 "object-0", settings=0x7fffe8014770) at panel-menu-bar.c:208
#7 0x000000000045d24e in panel_object_loader_idle_handler (
    dummy=<optimised out>) at panel-object-loader.c:219
#8 0x00007ffff549fd53 in g_main_dispatch (context=0x6a9ab0)
    at /build/buildd/glib2.0-2.32.3/./glib/gmain.c:2539
#9 g_main_context_dispatch (context=0x6a9ab0)
    at /build/buildd/glib2.0-2.32.3/./glib/gmain.c:3075
#10 0x00007ffff54a00a0 in g_main_context_iterate (dispatch=1,
    block=<optimised out>, context=0x6a9ab0, self=<optimised out>)
    at /build/buildd/glib2.0-2.32.3/./glib/gmain.c:3146
#11 g_main_context_iterate (context=0x6a9ab0, block=<optimised out>,
    dispatch=1, self=<optimised out>)
    at /build/buildd/glib2.0-2.32.3/./glib/gmain.c:3083
#12 0x00007ffff54a049a in g_main_loop_run (loop=0xa70210)
    at /build/buildd/glib2.0-2.32.3/./glib/gmain.c:3340
#13 0x00007ffff707d42d in gtk_main ()
   from /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#14 0x000000000042233f in main (argc=1, argv=0x7fffffffe088) at main.c:117

Alacarte also refuses to start with a xml parse error

$ lsb_release -rd
Description: Ubuntu 12.04.1 LTS
Release: 12.04

$ apt-cache policy gnome-panel
gnome-panel:
  Installed: 1:3.4.1-0ubuntu1.1
  Candidate: 1:3.4.1-0ubuntu1.1
  Version table:
 *** 1:3.4.1-0ubuntu1.1 0
        500 http://ftp.iinet.net.au/pub/ubuntu/ precise-updates/universe amd64 Packages
        100 /var/lib/dpkg/status
     1:3.4.1-0ubuntu1 0
        500 http://ftp.iinet.net.au/pub/ubuntu/ precise/universe amd64 Packages

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Rémi Pannequin (remi-pannequin-gmail)]

I also had this bug on a 12.04 machine.

Removing the empty file (~/.config/menus/applications.menu) solved the problem.

[penalvch (penalvch)]

adammw, thank you for reporting this and helping make Ubuntu better. However, your crash report is missing. Please follow these instructions to have apport report a new bug about your crash that can be dealt with by the automatic retracer. First, execute at a terminal:
cd /var/crash && sudo rm * ; sudo apt-get update && sudo apt-get -y upgrade && sudo apt-get -y install gnome-panel-dbg && sudo service apport start force_start=1

If you are running the Ubuntu Stable Release you might need to enable apport in /etc/default/apport and restart.

Now reproduce the crash, then open your file manager, navigate to your /var/crash directory and open the crash report you wish to submit.
If this fails you will have to open a terminal and file your report with 'ubuntu-bug /var/crash/_my_crash_report.crash' where _my_crash_report.crash is the crash you would like to report. If you get an error that you aren't allowed to access this report you will have to file it with 'sudo ubuntu-bug /var/crash/_my_crash_report.crash'. If you run the command against the crash report and a window pops up asking you to report this, but then never opens a new report, you would be affected by https://bugs.launchpad.net/ubuntu/+source/apport/+bug/994921 . In order to WORKAROUND this, one would need to open the following file via a command line:
gksudo gedit /etc/apport/crashdb.conf

and comment out the line:
'problem_types': ['Bug', 'Package'],

by changing it to:
# 'problem_types': ['Bug', 'Package'],

Save, close, and try to file the crash report again via:
ubuntu-bug /var/crash/_my_crash_report.crash

I'm closing this bug report since the process outlined above will automatically open a new bug report which can then dealt with more efficiently.

Please do not attach your crash report manually to this report and reopen it.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs