hp-systray segfault on quit

[smithj]

Binary package hint: hplip

This bug is derived from #497877. In that bug, a reviewer of my patch determined that hp-systray (sometimes) segfaults when you quit the tray app. I determined that the bug was also present in hplip without my patch.

Essentially, the python c module in pyqt can become... lets charitably call it "confused"... when python destroys objects in an order it isn't expecting. So, when exiting hplip, python's garbage collection runs (or doesn't) and triggers the edge case (or doesn't).

There are many discussions of this on the pyqt mailing lists, and each time the suggestion was to do one of the following:

1) instantiate your objects in a different order, until you find an order which doesn't cause the problem
2) figure out which object(s) is causing the issue, and explicitly kill it before you call QApplication.quit()

This message on the topic is somewhat enlightening: http://<email address hidden>/msg20499.html

[smithj (smithj)]

This one-line patch implements option #2 above.

[Launchpad Janitor (janitor)]

This bug was fixed in the package hplip - 3.10.2-1ubuntu4

---------------
hplip (3.10.2-1ubuntu4) lucid; urgency=low

  * debian/patches/hp-systray-segfault-on-quit.dpatch: Fixed a hp-systray to
    not segfaulting when quitting the program (LP: #546816).
 -- Till Kamppeter <email address hidden> Thu, 25 Mar 2010 13:51:18 +0100

[Till Kamppeter (till-kamppeter)]

Can someone at HP please apply this patch also to the upstream HPLIP source. Thanks.

[Naga Samrat Chowdary, Narla (samrat-hplip)]

Thanks Till Kanppeter,

Patch has been applied.
Similar patch also available at https://bugs.launchpad.net/hplip/+bug/486698.

Thanks for your contribution towards HPLIP,
Naga Samrat Chowdary, Narla