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Author vstinner
Recipients asvetlov, vstinner, yselivanov
Date 2020-03-30.16:53:45
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <>
The leak was introduced by:

commit b61b818d916942aad1f8f3e33181801c4a1ed14b (HEAD, refs/bisect/bad)
Author: Kyle Stanley <>
Date:   Fri Mar 27 15:31:22 2020 -0400

    bpo-39812: Remove daemon threads in concurrent.futures (GH-19149)
    Remove daemon threads from :mod:`concurrent.futures` by adding
    an internal `threading._register_atexit()`, which calls registered functions
    prior to joining all non-daemon threads. This allows for compatibility
    with subinterpreters, which don't support daemon threads.

The leaking test is:

$ ./python -m test --fail-env-changed -R 3:3 test_asyncio -m test.test_asyncio.test_events.EPollEventLoopTests.test_run_in_executor_cancel
0:00:00 load avg: 0.56 Run tests sequentially
0:00:00 load avg: 0.56 [1/1] test_asyncio
beginning 6 repetitions
test_asyncio leaked [1, 1, 1] references, sum=3
test_asyncio leaked [2, 1, 1] memory blocks, sum=4
test_asyncio failed

== Tests result: FAILURE ==

1 test failed:

Total duration: 4.2 sec
Tests result: FAILURE
Date User Action Args
2020-03-30 16:53:46vstinnersetrecipients: + vstinner, asvetlov, yselivanov
2020-03-30 16:53:46vstinnersetmessageid: <>
2020-03-30 16:53:46vstinnerlinkissue40115 messages
2020-03-30 16:53:45vstinnercreate