test_threadsignals hangs on "x86 Tiger 3.x" and "PPC Tiger 3.x":
---------------------
[279/354] test_threadsignals
Thread 0xa000d000:
  File "/Users/db3l/buildarea/3.x.bolen-tiger/build/Lib/test/test_threadsignals.py", line 46 in test_signals
  File "/Users/db3l/buildarea/3.x.bolen-tiger/build/Lib/unittest/case.py", line 387 in _executeTestPart
  File "/Users/db3l/buildarea/3.x.bolen-tiger/build/Lib/unittest/case.py", line 442 in run
  File "/Users/db3l/buildarea/3.x.bolen-tiger/build/Lib/unittest/case.py", line 494 in __call__
  File "/Users/db3l/buildarea/3.x.bolen-tiger/build/Lib/unittest/suite.py", line 105 in run
  File "/Users/db3l/buildarea/3.x.bolen-tiger/build/Lib/unittest/suite.py", line 67 in __call__
  File "/Users/db3l/buildarea/3.x.bolen-tiger/build/Lib/unittest/suite.py", line 105 in run
  File "/Users/db3l/buildarea/3.x.bolen-tiger/build/Lib/unittest/suite.py", line 67 in __call__
  File "/Users/db3l/buildarea/3.x.bolen-tiger/build/Lib/test/support.py", line 1078 in run
  File "/Users/db3l/buildarea/3.x.bolen-tiger/build/Lib/test/support.py", line 1166 in _run_suite
  File "/Users/db3l/buildarea/3.x.bolen-tiger/build/Lib/test/support.py", line 1192 in run_unittest
  File "/Users/db3l/buildarea/3.x.bolen-tiger/build/Lib/test/test_threadsignals.py", line 210 in test_main
  File "./Lib/test/regrtest.py", line 1032 in runtest_inner
  File "./Lib/test/regrtest.py", line 826 in runtest
  File "./Lib/test/regrtest.py", line 650 in main
  File "./Lib/test/regrtest.py", line 1607 in <module>
make: *** [buildbottest] Error 1
program finished with exit code 2
elapsedTime=3365.320090
---------------------
http://www.python.org/dev/buildbot/all/builders/x86%20Tiger%203.x/builds/2289/steps/test/logs/stdio
http://www.python.org/dev/buildbot/all/builders/PPC%20Tiger%203.x/builds/1700/steps/test/logs/stdio

test_threadsignals hangs at:
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class ThreadSignals(unittest.TestCase):
    def test_signals(self):
        signalled_all.acquire()
        self.spawnSignallingThread()
        signalled_all.acquire() <~~~~ here
----------------

self.spawnSignallingThread() calls:
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def send_signals():
    os.kill(process_pid, signal.SIGUSR1)
    os.kill(process_pid, signal.SIGUSR2)
    signalled_all.release()
----------------

The hang may be related to regrtest timeout: faulthandler had a bug, but the bug is supposed to be fixed (#11753, #11755).

See also issue #11223.