When debugging infinite-loop issues, it can sometimes be useful to enable dropping to debugger upon Ctrl+C. Currently --pdb only catches other exceptions, KeyboardInterrupt is specifically ignored (runner.py:193, CallInfo.__init__). It would be nice to have a switch that makes it swallow KeyboardInterrupt-s as well instead. It would of course make it harder to quit (although a few consecutive Ctrl+C's usually due the trick), but it's a reasonable price to pay for those cases.