Segfault in compiz when unchecking "Snap windows back to original size" in the Grid options

[asala]

This is it, compiz crashes at the moment the "snap windows back to original size" is unchecked.

Ubuntu 11.10 64 bit
Kernel 3.0.0-16-generic
with the latest updates... but keeps doing it since I insalled 11.10 back in November.

>> dpkg -s compiz-plugins
Package: compiz-plugins
Status: install ok installed
Priority: optional
Section: x11
Installed-Size: 2952
Maintainer: Ubuntu Developers <email address hidden>
Architecture: amd64
Source: compiz
Version: 1:0.9.6+bzr20110929-0ubuntu6.1

It is, likely, the same bug as the one reported in
http://askubuntu.com/questions/71950/compizconfig-killed-unity-only-unity2d-works-now

by a different user.

[Daniel van Vugt (vanvugt)]

Confirmed and reproduced the crash. Once I finally got the box unchecked, I found compiz continuously crashed on login thereafter making the system unusable:

(gdb) bt
#0 0x00007f67fb1e9d6a in PluginClassHandler<GridWindow, CompWindow, 0>::get(CompWindow*) () from /usr/lib/compiz/libgrid.so
#1 0x00007f67fb1e45cb in GridScreen::snapbackOptionChanged(CompOption*, GridOptions::Options) () from /usr/lib/compiz/libgrid.so
#2 0x00007f67fb1ec930 in GridOptions::setOption(std::string const&, CompOption::Value&) () from /usr/lib/compiz/libgrid.so
#3 0x0000000000427fc4 in CompScreen::setOptionForPlugin(char const*, char const*, CompOption::Value&) ()
#4 0x00007f6800803e2e in CcpScreen::setOptionForPlugin(char const*, char const*, CompOption::Value&) () from /usr/lib/compiz/libccp.so
#5 0x0000000000428013 in CompScreen::setOptionForPlugin(char const*, char const*, CompOption::Value&) ()
#6 0x00007f67fb60cd4c in WallScreen::setOptionForPlugin(char const*, char const*, CompOption::Value&) () from /usr/lib/compiz/libwall.so
#7 0x0000000000428013 in CompScreen::setOptionForPlugin(char const*, char const*, CompOption::Value&) ()
#8 0x00007f68008040e4 in CcpScreen::setOptionFromContext(CompOption*, char const*) () from /usr/lib/compiz/libccp.so
#9 0x00007f680080479c in CcpScreen::initPluginForScreen(CompPlugin*) () from /usr/lib/compiz/libccp.so
#10 0x000000000045a208 in CompScreen::initPluginForScreen(CompPlugin*) ()
#11 0x0000000000459ff0 in CompManager::initPlugin(CompPlugin*) ()
#12 0x000000000045bafe in CompPlugin::push(CompPlugin*) ()
#13 0x00000000004315df in PrivateScreen::updatePlugins() ()
#14 0x0000000000431aa3 in PrivateScreen::processEvents() ()
#15 0x000000000045ea61 in CompEventSource::callback() ()
#16 0x00007f6808ead9df in Glib::Source::dispatch_vfunc(_GSource*, int (*)(void*), void*) () from /usr/lib/libglibmm-2.4.so.1
#17 0x00007f68089b3a5d in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#18 0x00007f68089b4258 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#19 0x00007f68089b4429 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#20 0x00007f6808eae913 in Glib::MainContext::iteration(bool) () from /usr/lib/libglibmm-2.4.so.1
#21 0x000000000042e839 in CompScreen::eventLoop() ()
#22 0x00000000004221fa in main ()
(gdb)

[Daniel van Vugt (vanvugt)]

To fix the continuous crashing problem, go to a virtual terminal (Ctrl+Alt+F1) and edit:
~/.gconf/apps/compiz-1/plugins/grid/screen0/options/%gconf.xml

Find the line:
    <entry name="snapback_windows" ...
and change:
    value="false"
to:
    value="true"

Now run:
    sudo restart lightdm
and you should be able to log in again without compiz crashing.

[peter mueller (grandmastermt2000)]

The crash happens in either Unity or Gnome Fallback (with effects) with the newest version of Ubuntu 12.04 100% of the time, when unchecking the option as described in the description.

There seem to be multiple bug reports about this.

[Gareth Bailey (garethbailey0)]

This patch fixes the segfault. The option however does not work in part due to the underliing reasons for this bug.

https://bugs.launchpad.net/ubuntu/+source/compiz-plugins-main/+bug/879218

[Gareth Bailey (garethbailey0)]

And http://www.cl.cam.ac.uk/~gpb29/compiz-plugins-main-default_0.9.7.0~bzr19-0ubuntu10_amd64.deb should fix this for the impatient x64 users.

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "Fix-segfault-on-snapback-option-change" of this bug report has been identified as being a patch. The ubuntu-reviewers team has been subscribed to the bug report so that they can review the patch. In the event that this is in fact not a patch you can resolve this situation by removing the tag 'patch' from the bug report and editing the attachment so that it is not flagged as a patch. Additionally, if you are member of the ubuntu-reviewers team please also unsubscribe the team from this bug report.

[This is an automated message performed by a Launchpad user owned by Brian Murray. Please contact him regarding any issues with the action taken in this bug report.]

[Gareth Bailey (garethbailey0)]

Fixes now available in my ppa:
https://launchpad.net/~garethbailey0/+archive/ppa

[Daniel van Vugt (vanvugt)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. This particular bug has already been reported and is a duplicate of bug 745159, so it is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Feel free to continue to report any other bugs you may find.