test_multiprocessing_fork.test_terminate() failed twice on AMD64 Debian PGO 3.x:

https://buildbot.python.org/all/#/builders/47/builds/3699

0:23:37 load avg: 0.01 [419/419/1] test_multiprocessing_fork crashed (Exit code 1)
Timeout (0:15:00)!
Thread 0x00007f0272748700 (most recent call first):
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/multiprocessing/connection.py", line 379 in _recv
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/multiprocessing/connection.py", line 414 in _recv_bytes
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/multiprocessing/connection.py", line 250 in recv
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/multiprocessing/pool.py", line 599 in _handle_results
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/threading.py", line 882 in run
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/threading.py", line 944 in _bootstrap_inner
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/threading.py", line 902 in _bootstrap

Thread 0x00007f027a8a6500 (most recent call first):
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/multiprocessing/pool.py", line 674 in _help_stuff_finish
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/multiprocessing/pool.py", line 689 in _terminate_pool
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/multiprocessing/util.py", line 201 in __call__
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/multiprocessing/pool.py", line 656 in terminate
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/test/_test_multiprocessing.py", line 2521 in test_terminate
...
0:23:37 load avg: 0.01 Re-running test_multiprocessing_fork in verbose mode
...
test_starmap (test.test_multiprocessing_fork.WithProcessesTestPool) ... ok
test_starmap_async (test.test_multiprocessing_fork.WithProcessesTestPool) ... ok
Timeout (0:15:00)!
Thread 0x00007f251d553700 (most recent call first):
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/multiprocessing/connection.py", line 379 in _recv
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/multiprocessing/connection.py", line 414 in _recv_bytes
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/multiprocessing/connection.py", line 250 in recv
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/multiprocessing/pool.py", line 599 in _handle_results
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/threading.py", line 882 in run
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/threading.py", line 944 in _bootstrap_inner
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/threading.py", line 902 in _bootstrap

Thread 0x00007f2523e76500 (most recent call first):
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/multiprocessing/pool.py", line 674 in _help_stuff_finish
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/multiprocessing/pool.py", line 689 in _terminate_pool
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/multiprocessing/util.py", line 201 in __call__
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/multiprocessing/pool.py", line 656 in terminate
  File "/var/lib/buildbot/slaves/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/test/_test_multiprocessing.py", line 2521 in test_terminate