gnome-panel crashed with SIGSEGV in panel_widget_size_allocate()

[penalvch]

Super+Alt > secondary click empty area of panel > Properties > unchecked Expand and Auto Hide, tried to click again and then the gnome-panel application crashed. Limited impact on the panel itself, as both the top and bottom one remain working, with all expected icons, windows, etc.

ProblemType: Crash
DistroRelease: Ubuntu 15.04
Package: gnome-panel 1:3.14.0-2ubuntu1
ProcVersionSignature: Ubuntu 3.19.0-9.9-generic 3.19.1
Uname: Linux 3.19.0-9-generic x86_64
ApportVersion: 2.16.2-0ubuntu4
Architecture: amd64
CurrentDesktop: GNOME-Flashback:Unity
Date: Tue Mar 24 18:03:57 2015
ExecutablePath: /usr/bin/gnome-panel
GsettingsChanges:
 b'org.gnome.gnome-panel.run-dialog' b'show-program-list' b'true'
 b'org.gnome.gnome-panel.run-dialog' b'history' b"['xrandr --output LVDS --mode 1024x768', 'unity-control-center display', 'sudo reboot', 'sudo nautilus', 'nautilus']"
InstallationDate: Installed on 2014-06-21 (276 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
ProcCmdline: gnome-panel
ProcEnviron:
 LANGUAGE=en_US
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0x426221: mov 0x4(%rdx,%r9,8),%r9d
 PC (0x00426221) ok
 source "0x4(%rdx,%r9,8)" (0x00000004) not located in a known VMA region (needed readable region)!
 destination "%r9d" ok
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: gnome-panel
StacktraceTop:
 ?? ()
 g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
 ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
 g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
 g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
Title: gnome-panel crashed with SIGSEGV in g_closure_invoke()
UpgradeStatus: Upgraded to vivid on 2015-03-13 (11 days ago)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo

[Apport retracing service (apport)]

StacktraceTop:
 panel_widget_size_allocate (widget=<optimized out>, allocation=0x7ffddb053ea0) at panel-widget.c:1411
 g_closure_invoke (closure=0x20bca80, return_value=0x0, n_param_values=2, param_values=0x7ffddb053bd0, invocation_hint=0x7ffddb053b70) at /build/buildd/glib2.0-2.43.92/./gobject/gclosure.c:768
 signal_emit_unlocked_R (node=node@entry=0x20bce50, detail=detail@entry=0, instance=instance@entry=0x226c120, emission_return=emission_return@entry=0x0, instance_and_params=instance_and_params@entry=0x7ffddb053bd0) at /build/buildd/glib2.0-2.43.92/./gobject/gsignal.c:3479
 g_signal_emit_valist (instance=<optimized out>, signal_id=<optimized out>, detail=<optimized out>, var_args=var_args@entry=0x7ffddb053d60) at /build/buildd/glib2.0-2.43.92/./gobject/gsignal.c:3305
 g_signal_emit (instance=<optimized out>, signal_id=<optimized out>, detail=<optimized out>) at /build/buildd/glib2.0-2.43.92/./gobject/gsignal.c:3361

[penalvch (penalvch)]

Not reproducible in Wily.