unity-panel-service crashed with SIGSEGV in append_children()

[littlelion]

unity-panel-service crashes since the update to utopic - there should be plenty of auto-generated bug reports similar to this one. It keeps crashing in vivid and now in wily. It should be a new issue, because the older similar reports are from 2012 and are tagged as fixed.

Usually the crash happens after the menu bar stalled for a few seconds, but most of the time just the crash report pops up.

May be it is relavant to this bug: sometimes the kactivitymanagerd crashes immediately after the unity-panel-service (also uploaded by apport).

ProblemType: Crash
DistroRelease: Ubuntu 15.10
Package: unity-services 7.3.2+15.10.20151016-0ubuntu1 [origin: unknown]
ProcVersionSignature: Ubuntu 4.2.0-16.19-generic 4.2.3
Uname: Linux 4.2.0-16-generic x86_64
ApportVersion: 2.19.1-0ubuntu3
Architecture: amd64
CompizPlugins: [core,composite,opengl,compiztoolbox,decor,vpswitch,snap,mousepoll,resize,place,move,wall,grid,regex,imgpng,session,gnomecompat,animation,fade,unitymtgrabhandles,workarounds,scale,expo,ezoom,unityshell]
CrashCounter: 1
CrashDB: unity
CurrentDesktop: Unity
Date: Mon Dec 7 23:11:03 2015
ExecutablePath: /usr/lib/unity/unity-panel-service
InstallationDate: Installed on 2012-10-16 (1147 days ago)
InstallationMedia: Ubuntu 12.04.1 LTS "Precise Pangolin" - Release amd64 (20120823.1)
ProcCmdline: /usr/lib/unity/unity-panel-service
SegvAnalysis:
 Segfault happened at: 0x406eab: mov 0x0(%rbp),%rdx
 PC (0x00406eab) ok
 source "0x0(%rbp)" (0x0000002a) not located in a known VMA region (needed readable region)!
 destination "%rdx" ok
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: unity
StacktraceTop:
 ?? ()
 ?? () from /usr/lib/x86_64-linux-gnu/libatk-bridge-2.0.so.0
 g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
 ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
 g_main_loop_run () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
Title: unity-panel-service crashed with SIGSEGV in g_main_context_dispatch()
UpgradeStatus: Upgraded to wily on 2015-10-22 (46 days ago)
UserGroups: adm cdrom dialout dip lpadmin plugdev sambashare sudo wireshark

[Apport retracing service (apport)]

StacktraceTop:
 ?? ()
 append_children (traversal=0x7f42100012e0, accessible=0x2fb6850) at accessible-cache.c:233
 add_pending_items (data=<optimized out>) at accessible-cache.c:285
 g_main_dispatch (context=0x25d5720) at /build/glib2.0-ajuDY6/glib2.0-2.46.1/./glib/gmain.c:3154
 g_main_context_dispatch (context=context@entry=0x25d5720) at /build/glib2.0-ajuDY6/glib2.0-2.46.1/./glib/gmain.c:3769

[littlelion (the-littlelion)]

Small update:
I thought, there are no visible effects to the user interface, but there are:

This times it happened again while using TexStudio.
After the crash, the menu bar (top-down menu) of the application vanished completely.
To resume from this state it's necessary to close and reopen the program.

For now, I've no evidence, but the same issue could affect other applications too.