Searching with the app drawer causes Unity 8 to crash in some circumstances

I've tried this for a while now but couldn't see it happen. Would it be possible for you to attach a stack trace?

StackTrace: https://paste.ubuntu.com/23852328/

running "bt full" in gdb: https://paste.ubuntu.com/23852354/

and all the threads: https://paste.ubuntu.com/23852359/

Testing out the new branch, I seem to run into the same issue: https://paste.ubuntu.com/23853150/

Are you really sure you used the new packages? The lines in the stack trace indicate you'd still be running the original packages.

Hmm `apt-cache policy unity8` returned:

    8.15+17.04.20170110.4+fetch3933bzr2740-0ubuntu1

I can try to download/install the packages again.

Here's the new backtrace: https://paste.ubuntu.com/23858569/

I'm also able to reproduce this consistently in a kvm running xenial+overlay. Perhaps this has something to do with calling into libubuntu-app-launch to get libertine apps? I've got plenty of libertine apps in both of these environments that I search for.

I did an experiment where I removed any libertine apps from my system. At that point, I was unable to reproduce this defect. Then I installed "sakura" and "xterm" directly on my system and tried again. When alternating between searching for sakura and xterm in the search bar, I consistently see this crash. The crash *always* happens after I type "sa" but before the "a" appears in the search bar. "sakura" shows up in the app drawer, but the system then hangs briefly and crashes.

Ok, I can reproduce this now. Some findings:

I seems to only happen when searching for "xt" (xterm), then searching something in the "S" section and when the search result gives only one result within that section after the second letter. E.g. for me it crashes when searching for "sa" (sakura), "su" (sudoku) and "sn" (screenshot) but not with anything else in the "S" section.

Also, the "S" section is the largest one for me. I could not find any other section where it happens.

The speed at which the search is done doesn't matter... It is even possible to

search "xterm", delete that, type "s", switch to another vt, attach gdb to unity8, switch back and then type "a" to make it happen.

Sadly, the stack traces always seem to end up in some Qt metacall magic for invalidating the filters.

This bug was fixed in the package unity8 - 8.15+17.04.20170216.1-0ubuntu1

---------------
unity8 (8.15+17.04.20170216.1-0ubuntu1) zesty; urgency=medium

  [ Albert Astals Cid ]
  * Make menus items close the menu when clicking on them (LP: #1657082,
    #1657399)
  * Clicking on an open menu closes it + test
  * Make the menus and submenus do not go outside the screen when
    popping out
  * Auto open submenus on hover (LP: #1657085)
  * Make the double click on a menu not be maximize the window below
    (LP: #1657079)
  * Make the MenuBar InverseMouseArea eat hover events when there's a
    popup open (LP: #1657763)
  * Make double click on the window decoration maximize (LP: #1657758)
  * Eat hover events when the launcher quicklist is open (LP: #1640776)
  * Remove TODO now that we require Qt > 5.5
  * Serialize two make targets that want to cp to the same target file
    (LP: #1660576)
  * Remove variable that is always false (LP: #1585910)

  [ Daniel d'Andrada ]
  * Consolidate launcher API checks

  [ Lukáš Tinkl ]
  * Fixes for activating minimized windows and restoring fullscreen ones
    (LP: #1656808, #1658937, #1658938)

  [ Michael Zanetti ]
  * move right edge push area up some levels so it can be used on top of
    the indicators
  * fix minimizing/restoring transitions (LP: #1658936)
  * fix some glitches with spread positioning
  * fix jumpy animation when closing an item from the spread
  * Show the wallpaper while the focused app is moving in staged mode
    (LP: #1648251)
  * Update the tutorial to mention the app drawer instead of the dash on
    long left edge swipe (LP: #1658932)
  * prevent hiding the launcher when the mouse hover event is eaten by
    the EdgePushArea (LP: #1657045)
  * properly invalidate the whole model (LP: #1658190)
  * stabilize OrientedShell test (LP: #1658994)

  [ Nick Dedekind ]
  * Added overflow support to application menus.
  * Updated menu colors

 -- Michał Sawicz <email address hidden> Thu, 16 Feb 2017 13:49:18 +0000