This toy program:

import asyncio
@asyncio.coroutine
def main():
    p = yield from asyncio.create_subprocess_shell('echo hi')
    yield from p.wait()
asyncio.get_event_loop().run_until_complete(main())

Produces this output on Arch Linux under Python 3.4.3 (but not 3.4.2):

hi
Exception ignored in: <bound method _UnixSelectorEventLoop.__del__ of <_UnixSelectorEventLoop running=False closed=True debug=False>>
Traceback (most recent call last):
  File "/home/jacko/Downloads/Python-3.4.3/Lib/asyncio/base_events.py", line 361, in __del__
  File "/home/jacko/Downloads/Python-3.4.3/Lib/asyncio/unix_events.py", line 57, in close
  File "/home/jacko/Downloads/Python-3.4.3/Lib/asyncio/unix_events.py", line 138, in remove_signal_handler
TypeError: signal handler must be signal.SIG_IGN, signal.SIG_DFL, or a callable object