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Author vstinner
Recipients ajaksu2, bsilverthorn, iritkatriel, pitrou, vstinner
Date 2021-06-29.01:30:14
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <>
This issue was fixed differently in bpo-44263, by adding a test in PyType_Ready():

    // bpo-44263: tp_traverse is required if Py_TPFLAGS_HAVE_GC is set.
    // Note: tp_clear is optional.
    if (type->tp_flags & Py_TPFLAGS_HAVE_GC
        && type->tp_traverse == NULL)
                     "type %s has the Py_TPFLAGS_HAVE_GC flag "
                     "but has no traverse function",
        return -1;

commit ee7637596d8de25f54261bbeabc602d31e74f482
Author: Victor Stinner <>
Date:   Tue Jun 1 23:37:12 2021 +0200

    bpo-44263: Py_TPFLAGS_HAVE_GC requires tp_traverse (GH-26463)
    The PyType_Ready() function now raises an error if a type is defined
    with the Py_TPFLAGS_HAVE_GC flag set but has no traverse function
Date User Action Args
2021-06-29 01:30:14vstinnersetrecipients: + vstinner, pitrou, ajaksu2, bsilverthorn, iritkatriel
2021-06-29 01:30:14vstinnersetmessageid: <>
2021-06-29 01:30:14vstinnerlinkissue1662 messages
2021-06-29 01:30:14vstinnercreate