[PyQt] internalPointer crashes

[Joel B. Mohler]

Hi,

Back in April of this year Jeremy Sanders reported crashes when storing a 
python object in QModelIndex internalPointer.  I've had crashes of this nature 
as well.  It seems to work the vast majority of the time but I now have a case 
that seems to consistently crash although not always with the same error.

Jeremy's report is at http://www.riverbankcomputing.com/pipermail/pyqt/2011-
April/029719.html .  The suggestion in replies there was to make sure that 
python had pointers to all the things in internalPointer -- I'm quite certain 
that my python object structure does in fact have live references so I think 
there is an additional bug (although maintaining live python references seems 
quite sensible to me).

I'm currently on ubuntu 11.04 with PyQt 4.8.3 and Qt 4.7.2.  I think this same 
crash is happening on windows vista (with Qt versions I don't have at the 
moment).  My model source is at 
https://bitbucket.org/jbmohler/qtalchemy/src/69e8f006fee2/qtalchemy/PyQtModels.py 
in the class PBTableModel.  I'd have to work a bit to prune this down to 
something self-complete.

Of additional note is that converting everything in sight to PySide results in 
a non-crashing application.  I'm hesitant to rush off to PySide on the basis 
of this bug, but it's tempting.

Joel