s390x Debian 3.x: https://buildbot.python.org/all/#/builders/13/builds/2344 0:06:26 load avg: 0.92 [291/420/1] test_slice crashed (Exit code -6) Modules/gcmodule.c:110: gc_decref: Assertion "gc_get_refs(g) > 0" failed: refcount is too small Enable tracemalloc to get the memory block allocation traceback object : <test.test_slice.SliceTest.test_cmp..BadCmp object at 0x3ff93967e90> type : BadCmp refcount: 1 address : 0x3ff93967e90 Fatal Python error: _PyObject_AssertFailed Current thread 0x000003ff95272700 (most recent call first): File "/home/dje/cpython-buildarea/3.x.edelsohn-debian-z/build/Lib/test/test_slice.py", line 107 in File "/home/dje/cpython-buildarea/3.x.edelsohn-debian-z/build/Lib/unittest/case.py", line 197 in handle File "/home/dje/cpython-buildarea/3.x.edelsohn-debian-z/build/Lib/unittest/case.py", line 782 in assertRaises File "/home/dje/cpython-buildarea/3.x.edelsohn-debian-z/build/Lib/test/test_slice.py", line 107 in test_cmp File "/home/dje/cpython-buildarea/3.x.edelsohn-debian-z/build/Lib/unittest/case.py", line 642 in run File "/home/dje/cpython-buildarea/3.x.edelsohn-debian-z/build/Lib/unittest/case.py", line 702 in __call__ ...
I'm unable to reproduce the issue on my Fedora 29 (x86-64) laptop. I used two terminals: * ./python -m test -F -j0 test_slice test_slice test_slice test_slice test_slice test_slice test_slice test_slice * ./python -m test -j0 -u all,-gui -r # stress the system to randomize timings in test_slice