Hi All, The following extension module (AA) is a reduced example of what I'm doing to make extension classes in 2.2. I followed the examples given by typeobject.c. When I "import AA,pdb" I get a crash in GC. Investigating further, I see this makes sense: GC is enabled in class_metatype_object, yet class_type_object does not follow the first rule of objects whose type has GC enabled: "The memory for the object must be allocated using PyObject_GC_New() or PyObject_GC_VarNew()." So, I guess the question is, how does PyBaseObject_Type (also statically allocated) get away with it? TIA, Dave ---------------- // Copyright David Abrahams 2002. Permission to copy, use, // modify, sell and distribute this software is granted provided this // copyright notice appears in all copies. This software is provided // "as is" without express or implied warranty, and with no claim as // to its suitability for any purpose. #include PyTypeObject class_metatype_object = { PyObject_HEAD_INIT(0) 0, "Boost.Python.class", PyType_Type.tp_basicsize, 0, 0, /* tp_dealloc */ 0, /* tp_print */ 0, /* tp_getattr */ 0, /* tp_setattr */ 0, /* tp_compare */ 0, /* tp_repr */ 0, /* tp_as_number */ 0, /* tp_as_sequence */ 0, /* tp_as_mapping */ 0, /* tp_hash */ 0, /* tp_call */ 0, /* tp_str */ 0, /* tp_getattro */ 0, /* tp_setattro */ 0, /* tp_as_buffer */ Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC | Py_TPFLAGS_BASETYPE, /* tp_flags */ 0, /* tp_doc */ 0, /* tp_traverse */ 0, /* tp_clear */ 0, /* tp_richcompare */ 0, /* tp_weaklistoffset */ 0, /* tp_iter */ 0, /* tp_iternext */ 0, /* tp_methods */ 0, /* tp_members */ 0, /* tp_getset */ 0, // &PyType_Type, /* tp_base */ 0, /* tp_dict */ 0, /* tp_descr_get */ 0, /* tp_descr_set */ 0, /* tp_dictoffset */ 0, /* tp_init */ 0, /* tp_alloc */ 0, // PyType_GenericNew /* tp_new */ }; // Get the metatype object for all extension classes. PyObject* class_metatype() { if (class_metatype_object.tp_dict == 0) { class_metatype_object.ob_type = &PyType_Type; class_metatype_object.tp_base = &PyType_Type; if (PyType_Ready(&class_metatype_object)) return 0; } Py_INCREF(&class_metatype_object); return (PyObject*)&class_metatype_object; } // Each extension instance will be one of these typedef struct instance { PyObject_HEAD void* objects; } instance; static void instance_dealloc(PyObject* inst) { instance* kill_me = (instance*)inst; inst->ob_type->tp_free(inst); } PyTypeObject class_type_object = { PyObject_HEAD_INIT(0) file://&class_metatype_object) 0, "Boost.Python.instance", sizeof(PyObject), 0, instance_dealloc, /* tp_dealloc */ 0, /* tp_print */ 0, /* tp_getattr */ 0, /* tp_setattr */ 0, /* tp_compare */ 0, /* tp_repr */ 0, /* tp_as_number */ 0, /* tp_as_sequence */ 0, /* tp_as_mapping */ 0, /* tp_hash */ 0, /* tp_call */ 0, /* tp_str */ 0, /* tp_getattro */ 0, /* tp_setattro */ 0, /* tp_as_buffer */ Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC | Py_TPFLAGS_BASETYPE, /* tp_flags */ 0, /* tp_doc */ 0, /* tp_traverse */ 0, /* tp_clear */ 0, /* tp_richcompare */ 0, /* tp_weaklistoffset */ 0, /* tp_iter */ 0, /* tp_iternext */ 0, /* tp_methods */ 0, /* tp_members */ 0, /* tp_getset */ 0, file://&PyBaseObject_Type, /* tp_base */ 0, /* tp_dict */ 0, /* tp_descr_get */ 0, /* tp_descr_set */ 0, /* tp_dictoffset */ 0, /* tp_init */ PyType_GenericAlloc, /* tp_alloc */ PyType_GenericNew }; PyObject* class_type() { if (class_type_object.tp_dict == 0) { class_type_object.ob_type = (PyTypeObject*)class_metatype(); class_type_object.tp_base = &PyBaseObject_Type; if (PyType_Ready(&class_type_object)) return 0; } Py_INCREF(&class_type_object); return (PyObject*)&class_type_object; } PyObject* make_class() { PyObject* bases, *args, *mt, *result; bases = PyTuple_New(1); PyTuple_SET_ITEM(bases, 0, class_type()); args = PyTuple_New(3); PyTuple_SET_ITEM(args, 0, PyString_FromString("AA")); PyTuple_SET_ITEM(args, 1, bases); PyTuple_SET_ITEM(args, 2, PyDict_New()); mt = class_metatype(); result = PyObject_CallObject(mt, args); Py_XDECREF(mt); Py_XDECREF(args); return result; } static PyMethodDef SpamMethods[] = { {NULL, NULL} /* Sentinel */ }; DL_EXPORT(void) initAA() { PyObject *m, *d; m = Py_InitModule("AA", SpamMethods); d = PyModule_GetDict(m); PyDict_SetItemString(d, "AA", make_class()); } +---------------------------------------------------------------+ David Abrahams C++ Booster (http://www.boost.org) O__ == Pythonista (http://www.python.org) c/ /'_ == resume: http://users.rcn.com/abrahams/resume.html (*) \(*) == email: david.abrahams@rcn.com +---------------------------------------------------------------+