The test fails randomly on POSIX platforms since r78527 (fixing issue #7242).
The failure is in the new TestCase: TestForkInThread.


 $ ./python -m test.regrtest -uall -R :: test_thread
test_thread
beginning 9 repetitions
123456789
Unhandled exception in thread started by <function thread1 at 0x26c3f78>
Traceback (most recent call last):
  File "./Lib/test/test_thread.py", line 218, in thread1
    os.close(self.write_fd)
OSError: [Errno 9] Bad file descriptor
.Unhandled exception in thread started by <function thread1 at 0x2863ae0>
Traceback (most recent call last):
  File "./Lib/test/test_thread.py", line 218, in thread1
    os.close(self.write_fd)
OSError: [Errno 9] Bad file descriptor
test test_thread failed -- Traceback (most recent call last):
  File "./Lib/test/test_thread.py", line 120, in test__count
    self.assertEquals(thread._count(), orig + 1)
AssertionError: 1 != 2

1 test failed:
    test_thread
Unhandled exception in thread started by 
Error in sys.excepthook:

Original exception was:

Fixed with r79127 and r79128.