I managed to hang on Ubuntu, here is the backtrace that I got with CTRL-C:

Process PoolWorker-5:1:
Traceback (most recent call last):
  File "/home/cartman/Sources/py3k/Lib/multiprocessing/process.py", line
232, in _bootstrap
    test_bsddb test_bsddb3 test_cProfile test_kqueue test_lib2to3
2 skips unexpected on linux2:
    test_bsddb3 test_bsddb
Process PoolWorker-5:3:
Traceback (most recent call last):
  File "/home/cartman/Sources/py3k/Lib/multiprocessing/process.py", line
232, in _bootstrap
    self.run()
  File "/home/cartman/Sources/py3k/Lib/multiprocessing/process.py", line
88, in run
    self._target(*self._args, **self._kwargs)
  File "/home/cartman/Sources/py3k/Lib/multiprocessing/pool.py", line
57, in worker
    self.run()
  File "/home/cartman/Sources/py3k/Lib/multiprocessing/process.py", line
88, in run
    self._target(*self._args, **self._kwargs)
  File "/home/cartman/Sources/py3k/Lib/multiprocessing/pool.py", line
57, in worker
    task = get()
  File "/home/cartman/Sources/py3k/Lib/multiprocessing/queues.py", line
339, in get
    task = get()
  File "/home/cartman/Sources/py3k/Lib/multiprocessing/queues.py", line
337, in get
    return recv()
  File "/home/cartman/Sources/py3k/Lib/pickle.py", line 1327, in loads
    racquire()
KeyboardInterrupt
Process PoolWorker-5:2:
Traceback (most recent call last):
  File "/home/cartman/Sources/py3k/Lib/multiprocessing/process.py", line
232, in _bootstrap
    self.run()
  File "/home/cartman/Sources/py3k/Lib/multiprocessing/process.py", line
88, in run
    self._target(*self._args, **self._kwargs)
  File "/home/cartman/Sources/py3k/Lib/multiprocessing/pool.py", line
57, in worker
    def loads(s, *, encoding="ASCII", errors="strict"):
KeyboardInterrupt
Process PoolWorker-5:4:
Traceback (most recent call last):
  File "/home/cartman/Sources/py3k/Lib/multiprocessing/process.py", line
232, in _bootstrap
    self.run()
  File "/home/cartman/Sources/py3k/Lib/multiprocessing/process.py", line
88, in run
    self._target(*self._args, **self._kwargs)
  File "/home/cartman/Sources/py3k/Lib/multiprocessing/pool.py", line
57, in worker
    task = get()
  File "/home/cartman/Sources/py3k/Lib/multiprocessing/queues.py", line
337, in get
    racquire()
KeyboardInterrupt
    task = get()
  File "/home/cartman/Sources/py3k/Lib/multiprocessing/queues.py", line
337, in get
    racquire()
KeyboardInterrupt
^CError in atexit._run_exitfuncs:
make: *** [testall] Segmentation fault