Failure on "x86 Ubuntu Shared 3.x" at revision af388201c9976aebc4a8a433c95bfc4a1abe014b. I added an assertion in tracemalloc_init() to ensure that the reeentrant flag is set at the end of the function. The reentrant flag was no more set at tracemalloc_start() entry for an unknown reason. http://buildbot.python.org/all/builders/x86%20Ubuntu%20Shared%203.x/builds/12905/steps/test/logs/stdio --- 0:08:50 [183/400] test_tracemalloc [pid 14926, tid 1437466048] tracemalloc_start() [pid 14926, tid 1437466048] tracemalloc_init() [pid 14926, tid 1437466048] tracemalloc_init(): exit (already initialized) python: ./Modules/_tracemalloc.c:1058: tracemalloc_start: Assertion `get_reentrant()' failed. Fatal Python error: Aborted Current thread 0x55adfdc0 (most recent call first): File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/test_tracemalloc.py", line 97 in setUp File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/unittest/case.py", line 596 in run File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/unittest/case.py", line 648 in __call__ File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/unittest/suite.py", line 122 in run File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/unittest/suite.py", line 84 in __call__ File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/unittest/suite.py", line 122 in run File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/unittest/suite.py", line 84 in __call__ File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/unittest/runner.py", line 176 in run File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/support/__init__.py", line 1802 in _run_suite File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/support/__init__.py", line 1836 in run_unittest File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/test_tracemalloc.py", line 999 in test_main File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/libregrtest/runtest.py", line 162 in runtest_inner File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/libregrtest/runtest.py", line 115 in runtest File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/libregrtest/main.py", line 306 in run_tests_sequential File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/libregrtest/main.py", line 367 in run_tests File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/libregrtest/main.py", line 405 in main File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/libregrtest/main.py", line 446 in main File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/libregrtest/main.py", line 468 in main_in_temp_cwd File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/test/__main__.py", line 3 in <module> File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/runpy.py", line 85 in _run_code File "/srv/buildbot/buildarea/3.x.bolen-ubuntu/build/Lib/runpy.py", line 184 in _run_module_as_main ---