Example of buildbot build which created a python.core file.

Tests crashing Python on purpose should use test.support.SuppressCrashReport. I don't see which test can crash in the following list.

http://buildbot.python.org/all/builders/AMD64%20FreeBSD%20CURRENT%20Non-Debug%203.x/builds/175/steps/test/logs/stdio

0:04:54 [132/404/6] test_raise passed -- running: test_subprocess (61 sec)
0:04:54 [133/404/6] test_dict passed -- running: test_subprocess (62 sec)
0:04:54 [134/404/6] test_telnetlib passed -- running: test_subprocess (62 sec)
0:04:55 [135/404/6] test_robotparser passed -- running: test_subprocess (63 sec)
0:04:56 [136/404/6] test_py_compile passed -- running: test_subprocess (64 sec)
0:04:56 [137/404/6] test_listcomps passed -- running: test_subprocess (64 sec)
0:04:56 [138/404/6] test_pty passed -- running: test_subprocess (64 sec)
0:04:56 [139/404/6] test_defaultdict passed -- running: test_subprocess (64 sec)
running: test_io (30 sec), test_subprocess (94 sec)
0:05:27 [140/404/6] test_subprocess passed (94 sec) -- running: test_io (31 sec)
0:05:27 [141/404/6] test_unpack passed -- running: test_io (31 sec)
0:05:28 [142/404/6] test_bytes passed -- running: test_io (33 sec)
0:05:29 [143/404/6] test_weakset passed -- running: test_io (33 sec)
0:05:36 [144/404/6] test_eintr passed -- running: test_io (40 sec)
0:05:37 [145/404/6] test_userstring passed -- running: test_io (41 sec)
0:05:37 [146/404/6] test_support passed -- running: test_io (41 sec)
0:05:37 [147/404/6] test_ioctl skipped -- running: test_io (42 sec)
test_ioctl skipped -- Unable to open /dev/tty
0:05:40 [148/404/6] test_cmd_line passed -- running: test_io (44 sec)
0:05:41 [149/404/6] test_turtle skipped -- running: test_io (45 sec)
test_turtle skipped -- No module named '_tkinter'
0:05:41 [150/404/6] test_subclassinit passed -- running: test_io (45 sec)
0:05:42 [151/404/6] test_set passed -- running: test_io (46 sec)
0:05:43 [152/404/6] test_xml_etree_c passed -- running: test_io (47 sec)
0:05:43 [153/404/6] test_binascii passed -- running: test_io (47 sec)
0:05:48 [154/404/6] test_normalization passed -- running: test_io (52 sec)
fetching http://www.pythontest.net/unicode/9.0.0/NormalizationTest.txt ...
0:05:49 [155/404/6] test_os passed -- running: test_io (54 sec)
stty: stdin isn't a terminal
0:05:50 [156/404/6] test_abc passed -- running: test_io (54 sec)
0:05:50 [157/404/6] test_dummy_threading passed -- running: test_io (54 sec)
0:05:50 [158/404/6] test_pkgutil passed -- running: test_io (54 sec)
0:05:50 [159/404/6] test_compile passed -- running: test_io (55 sec)
0:05:51 [160/404/6] test_largefile passed -- running: test_io (55 sec)
0:05:54 [161/404/6] test_io failed (env changed) (57 sec)
test_BufferedIOBase_destructor (test.test_io.CIOTest) ... ok
...
test_interrupted_write_unbuffered (test.test_io.PySignalsTest) ... ok
----------------------------------------------------------------------
Ran 565 tests in 57.439s

OK (skipped=2)
Warning -- files was modified by test_io
  Before: []
  After:  ['python.core']

New changeset 2a1aed04b0943636f605543522e16cca1dc23e70 by Victor Stinner in branch 'master':
bpo-30107: don't dump core on expected test_io crash (#1235)
https://github.com/python/cpython/commit/2a1aed04b0943636f605543522e16cca1dc23e70

New changeset b984a05d557e78b928f38098d0b6c0e95f737b9a by Victor Stinner in branch '3.6':
bpo-30107: don't dump core on expected test_io crash (#1235) (#1241)
https://github.com/python/cpython/commit/b984a05d557e78b928f38098d0b6c0e95f737b9a

The commit 2a1aed04b0943636f605543522e16cca1dc23e70 introduced a regression on macOS. The PR https://github.com/python/cpython/pull/1279 should fix it.

http://buildbot.python.org/all/builders/x86-64%20El%20Capitan%203.x/builds/87/steps/test/logs/stdio

======================================================================
FAIL: test_daemon_threads_shutdown_stderr_deadlock (test.test_io.CMiscIOTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/buildbot/buildarea/3.x.billenstein-elcapitan/build/Lib/test/test_io.py", line 3772, in test_daemon_threads_shutdown_stderr_deadlock
    self.check_daemon_threads_shutdown_deadlock('stderr')
  File "/Users/buildbot/buildarea/3.x.billenstein-elcapitan/build/Lib/test/test_io.py", line 3766, in check_daemon_threads_shutdown_deadlock
    self.assertFalse(err.strip('.!'))
AssertionError: '2017-04-24 16:57:21.432 defaults[41046:2462851] \nThe domain/default pair of (com.apple.CrashReporter, DialogType) does not exist\n' is not false

New changeset d819ad9832292d854e9710493ecdf959b69802e3 by Victor Stinner in branch 'master':
bpo-30107: Make SuppressCrashReport quiet on macOS (#1279)
https://github.com/python/cpython/commit/d819ad9832292d854e9710493ecdf959b69802e3

I'm waiting for buildbots to check if the issue is really fixed.

New changeset c9ca57eeea4d9da748d84281506c5803512b79ac by Victor Stinner in branch '3.6':
bpo-30107: Make SuppressCrashReport quiet on macOS (#1279) (#1335)
https://github.com/python/cpython/commit/c9ca57eeea4d9da748d84281506c5803512b79ac

New changeset 98c7a9e662b49029ff051b6699ddc0f542663c96 by Victor Stinner in branch '3.5':
[3.5] bpo-30107: don't dump core on expected test_io crash (#1235) (#1344)
https://github.com/python/cpython/commit/98c7a9e662b49029ff051b6699ddc0f542663c96

Oh, I forgot that issue. I'm now happy to be able to close it ;-) The bug was fixed!