Comment 2 for bug 847464

$ valgrind gnome-panel

...

(gnome-panel:3827): GLib-GObject-WARNING **: /build/buildd/glib2.0-2.29.90/./gobject/gsignal.c:2295: signal `size_request' is invalid for instance `0x1e185900'
==3827==
==3827== Process terminating with default action of signal 8 (SIGFPE)
==3827== Integer divide by zero at address 0x40BCD3499
==3827== at 0x17C628D2: ??? (in /usr/lib/libwnck-3.so.0.1.0)
==3827== by 0x70881A9: g_closure_invoke (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2990.0)
==3827== by 0x709ACD6: ??? (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2990.0)
==3827== by 0x70A4B16: g_signal_emit_valist (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2990.0)
==3827== by 0x70A4CE1: g_signal_emit (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2990.0)
==3827== by 0x573BE56: gtk_widget_size_allocate (in /usr/lib/libgtk-3.so.0.118.0)
==3827== by 0x556F120: ??? (in /usr/lib/libgtk-3.so.0.118.0)
==3827== by 0x17A3C99C: ??? (in /usr/lib/libpanel-applet-4.so.0.0.2)
==3827== by 0x70881A9: g_closure_invoke (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2990.0)
==3827== by 0x709ACD6: ??? (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2990.0)
==3827== by 0x70A4B16: g_signal_emit_valist (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2990.0)
==3827== by 0x70A4CE1: g_signal_emit (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2990.0)

The backtrace in gdb is bizarre:

$ gdb gnome-panel
GNU gdb (Ubuntu/Linaro 7.3-0ubuntu2) 7.3-2011.08
Copyright (C) 2011 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
For bug reporting instructions, please see:
<http://bugs.launchpad.net/gdb-linaro/>...
Reading symbols from /usr/bin/gnome-panel...(no debugging symbols found)...done.
(gdb) r
Starting program: /usr/bin/gnome-panel
[Thread debugging using libthread_db enabled]
[New Thread 0x7fffed50c700 (LWP 3849)]
[New Thread 0x7fffecb02700 (LWP 3850)]

(gnome-panel:3846): GLib-GObject-WARNING **: invalid cast from `PanelToplevel' to `GtkOrientable'

(gnome-panel:3846): Gtk-CRITICAL **: gtk_orientable_get_orientation: assertion `GTK_IS_ORIENTABLE (orientable)' failed
[New Thread 0x7fffe1d5d700 (LWP 3851)]
[New Thread 0x7fffe155c700 (LWP 3852)]
[New Thread 0x7fffe0d5b700 (LWP 3853)]

(gnome-panel:3846): GLib-GObject-WARNING **: /build/buildd/glib2.0-2.29.90/./gobject/gsignal.c:2295: signal `size_request' is invalid for instance `0xb4fa20'

Program received signal SIGFPE, Arithmetic exception.
0x00007fffe25928dc in ?? () from /usr/lib/libwnck-3.so.0
(gdb) bt
#0 0x00007fffe25928dc in ?? () from /usr/lib/libwnck-3.so.0
#1 0x00007ffff594f1aa in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#2 0x00007ffff5961cd7 in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#3 0x00007ffff596bb17 in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#4 0x00007ffff596bce2 in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#5 0x00007ffff73c3e57 in gtk_widget_size_allocate () from /usr/lib/libgtk-3.so.0
#6 0x00007ffff71f7121 in ?? () from /usr/lib/libgtk-3.so.0
#7 0x00007fffe27bc99d in ?? () from /usr/lib/libpanel-applet-4.so.0
#8 0x00007ffff594f1aa in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#9 0x00007ffff5961cd7 in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#10 0x00007ffff596bb17 in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#11 0x00007ffff596bce2 in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#12 0x00007ffff73c3e57 in gtk_widget_size_allocate () from /usr/lib/libgtk-3.so.0
#13 0x00007ffff73f5318 in ?? () from /usr/lib/libgtk-3.so.0
#14 0x00007ffff594f1aa in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#15 0x00007ffff5961cd7 in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#16 0x00007ffff596bb17 in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#17 0x00007ffff596bce2 in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#18 0x00007ffff73c3e57 in gtk_widget_size_allocate () from /usr/lib/libgtk-3.so.0
#19 0x00007ffff73f8c06 in ?? () from /usr/lib/libgtk-3.so.0
#20 0x00007ffff594f1aa in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#21 0x00007ffff5961cd7 in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#22 0x00007ffff596bb17 in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#23 0x00007ffff596bce2 in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#24 0x00007ffff73c3e57 in gtk_widget_size_allocate () from /usr/lib/libgtk-3.so.0
#25 0x00007ffff71f7121 in ?? () from /usr/lib/libgtk-3.so.0
#26 0x00007ffff594f1aa in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#27 0x00007ffff5961cd7 in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#28 0x00007ffff596bb17 in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#29 0x00007ffff596bce2 in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#30 0x00007ffff73c3e57 in gtk_widget_size_allocate () from /usr/lib/libgtk-3.so.0
#31 0x000000000043a88b in ?? ()
#32 0x00007ffff594f1aa in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#33 0x00007ffff5961cd7 in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#34 0x00007ffff596bb17 in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#35 0x00007ffff596bce2 in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#36 0x00007ffff73c3e57 in gtk_widget_size_allocate () from /usr/lib/libgtk-3.so.0
#37 0x0000000000424aff in ?? ()
#38 0x00007ffff594f1aa in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#39 0x00007ffff5961cd7 in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#40 0x00007ffff596bb17 in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#41 0x00007ffff596bce2 in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#42 0x00007ffff73c3e57 in gtk_widget_size_allocate () from /usr/lib/libgtk-3.so.0
#43 0x00000000004505eb in ?? ()
#44 0x00007ffff594f1aa in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#45 0x00007ffff5961cd7 in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#46 0x00007ffff596bb17 in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#47 0x00007ffff596bce2 in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#48 0x00007ffff73c3e57 in gtk_widget_size_allocate () from /usr/lib/libgtk-3.so.0
#49 0x00007ffff730c474 in ?? () from /usr/lib/libgtk-3.so.0
#50 0x00007ffff594f1aa in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#51 0x00007ffff5961cd7 in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#52 0x00007ffff596bb17 in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#53 0x00007ffff596bce2 in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#54 0x00007ffff73c3e57 in gtk_widget_size_allocate () from /usr/lib/libgtk-3.so.0
#55 0x0000000000447bdb in ?? ()
#56 0x00007ffff594f254 in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#57 0x00007ffff5961cd7 in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#58 0x00007ffff596bb17 in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#59 0x00007ffff596bce2 in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#60 0x00007ffff73c3e57 in gtk_widget_size_allocate () from /usr/lib/libgtk-3.so.0
#61 0x00000000004475be in ?? ()
#62 0x00007ffff594f254 in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#63 0x00007ffff5962334 in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#64 0x00007ffff596bb17 in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#65 0x00007ffff596bce2 in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#66 0x00007ffff71d72b8 in ?? () from /usr/lib/libgtk-3.so.0
#67 0x00007ffff6e93a9f in ?? () from /usr/lib/libgdk-3.so.0
#68 0x00007ffff548ab6d in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#69 0x00007ffff548b368 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#70 0x00007ffff548b8a2 in g_main_loop_run () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#71 0x00007ffff726a10d in gtk_main () from /usr/lib/libgtk-3.so.0
#72 0x00000000004220ef in main ()
(gdb)