[Discuss-gnuradio] qtgui sink - flakiness at deconstruction time

[Josh Blum]

I have noticed (either through direct observation, or people's reports
to me) that there is some "flakiness" when a flow graph with a qtgui
sink deconstructs.

(linux) When a flowgraph with a qtgui sink is shutdown, the
deconstructor for the uhd block does not get called.

(windows) When closing the gui app (sometimes), a windows pops up
telling me about an error and asking if i want to debug the program.
(this has also be reproduced with pyqt_example.py).

I think, that most likely, this is an issue of the qtgui deconstructor
throwing an exception. But I cannot say for sure.
http://www.parashift.com/c++-faq-lite/exceptions.html#faq-17.9

Any suggestions? Anyone else notice this issue?
-Josh