New submission from STINNER Victor <vstin...@redhat.com>:
test_asyncio started to crash in https://github.com/python/cpython/pull/7487 I debugged the crash with Yury: _PyHAMT_New() triggers indirectly a GC collection at "o->h_root = hamt_node_bitmap_new(0);". Problem: the object that is being created is already tracked by the GC, whereas its h_root field is not set. Then the GC does crash because the field is a random pointer. hamt_alloc() must initialize h_root and h_count before tracking the object in the GC. Thinking about the GC when writing an object constructor is hard :-( Maybe we should add a debug option to trigger the GC more often to make such random bug more likely. contextvars has been implemented a few months ago, and we only spotted the bug a few days before Python 3.7.0 final release... ---------- components: Interpreter Core messages: 318990 nosy: ned.deily, vstinner, yselivanov priority: release blocker severity: normal status: open type: crash versions: Python 3.7, Python 3.8 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue33803> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
