Not happy with Qt on OS X...

I really don't get happy with Qt 4.6 on OS X 10.6. Nokia rates Qt on that platform as Tier 2. Which means, it is not fully supported. This results in stupid things happening. With Licq, I currently have the problem that the whole program crashes with the following message:

+[NSUndoManager(NSInternal) _endTopLevelGroupings] is only safe to invoke on the main thread.

The problem here is that Qt 4.6 for 64 Bit is (rightly so) built using the Cocoa API, instead of the C-only Carbon API. Now it seems that Qt uses the NSUndoManager, which in turn has an undocumented (?) function _endTopLevelGroupings. And as the above mentioned message tells you, it is only safe to call that function from the main thread. Since the qt4-gui plugin of Licq runs in a separate thread, this assertion fails, and the whole program crashes. So this basically means you cannot start up your GUI from a secondary thread with Cocoa based Qt. This, I think, constitutes a bug in Qt.

Update: I submitted a bug tracker item, and erijo is producing a minimal example that will hopefully show the bug in action. Now let's wait and see.

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