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Author vstinner
Recipients gvanrossum, vstinner
Date 2013-11-17.22:53:22
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <>
On old FreeBSD versions, concurrent.futures cannot be used. I don't remember why, it's probably related to semaphores (something like a low hardcoded limit). See for example first lines of Lib/test/
# Skip tests if _multiprocessing wasn't built.   '_multiprocessing')   
# Skip tests if sem_open implementation is broken.               'multiprocessing.synchronize')
# import threading after _multiprocessing to raise a more revelant error  
# message: "No module named _multiprocessing". _multiprocessing is not compiled
# without thread support.'threading')

The problem is that asyncio always try to import concurrent.futures. Example:

test test_asyncio crashed -- Traceback (most recent call last):
  File "/usr/home/db3l/buildarea/3.x.bolen-freebsd/build/Lib/test/", line 1276, in runtest_inner
  File "/usr/home/db3l/buildarea/3.x.bolen-freebsd/build/Lib/test/test_asyncio/", line 31, in test_main
  File "/usr/home/db3l/buildarea/3.x.bolen-freebsd/build/Lib/test/test_asyncio/", line 21, in suite
  File "/usr/home/db3l/buildarea/3.x.bolen-freebsd/build/Lib/test/test_asyncio/", line 11, in <module>
    from asyncio import base_events
  File "/usr/home/db3l/buildarea/3.x.bolen-freebsd/build/Lib/asyncio/", line 21, in <module>
    from .futures import *
  File "/usr/home/db3l/buildarea/3.x.bolen-freebsd/build/Lib/asyncio/", line 21, in <module>
    Error = concurrent.futures._base.Error
AttributeError: 'module' object has no attribute 'futures'
Date User Action Args
2013-11-17 22:53:22vstinnersetrecipients: + vstinner, gvanrossum
2013-11-17 22:53:22vstinnersetmessageid: <>
2013-11-17 22:53:22vstinnerlinkissue19635 messages
2013-11-17 22:53:22vstinnercreate