New submission from Christoph Gohlke <cgoh...@uci.edu>:
When testing extension packages on Python 3.9.0b4 for Windows, I often get access violations in `python39.dll!meth_dealloc` during interpreter exit. The crash only happens when heap verification is turned on (`"C:\Program Files (x86)\Windows Kits\10\Debuggers\x86\gflags.exe" /p /enable python.exe`; https://docs.microsoft.com/en-us/windows-hardware/drivers/debugger/gflags). The debug build does not crash. Could be related to "PEP 573: Module State Access from C Extension Methods", https://bugs.python.org/issue38787 To reproduce the crash with with numpy-1.19.0 (built from source): ``` Python 3.9.0b4 (tags/v3.9.0b4:69dec9c, Jul 2 2020, 21:46:36) [MSC v.1924 64 bit (AMD64)] on win32 Type "help", "copyright", "credits" or "license" for more information. >>> import numpy;numpy.test() NumPy version 1.19.0 <snip> 10364 passed, 438 skipped, 108 deselected, 17 xfailed, 1 xpassed in 243.52s (0:04:03) True >>> exit() Windows fatal exception: access violation Current thread 0x00002688 (most recent call first): <no Python frame> ``` The crash is at <https://github.com/python/cpython/blob/1d1c5743400bdf384ec83eb6ba5b39a355d121e3/Objects/methodobject.c#L169>: ``` static void meth_dealloc(PyCFunctionObject *m) { _PyObject_GC_UNTRACK(m); if (m->m_weakreflist != NULL) { PyObject_ClearWeakRefs((PyObject*) m); } Py_XDECREF(m->m_self); Py_XDECREF(m->m_module); Py_XDECREF(PyCFunction_GET_CLASS(m)); /* <-- crash */ PyObject_GC_Del(m); } ``` Call Stack: ``` > python39.dll!meth_dealloc(PyCFunctionObject * m) Line 169 C [Inline Frame] python39.dll!_Py_Dealloc(_object *) Line 2209 C [Inline Frame] python39.dll!_Py_DECREF(_object *) Line 430 C [Inline Frame] python39.dll!_Py_XDECREF(_object * op) Line 497 C [Inline Frame] python39.dll!free_keys_object(_dictkeysobject *) Line 598 C [Inline Frame] python39.dll!dictkeys_decref(_dictkeysobject *) Line 333 C python39.dll!dict_dealloc(PyDictObject * mp) Line 2026 C [Inline Frame] python39.dll!_Py_Dealloc(_object *) Line 2209 C [Inline Frame] python39.dll!_Py_DECREF(_object *) Line 430 C python39.dll!_PyInterpreterState_ClearModules(_is * interp) Line 768 C python39.dll!_PyImport_Cleanup(_ts * tstate) Line 628 C python39.dll!Py_FinalizeEx() Line 1432 C python39.dll!Py_Exit(int sts) Line 2433 C python39.dll!handle_system_exit() Line 696 C python39.dll!_PyErr_PrintEx(_ts * tstate, int set_sys_last_vars) Line 708 C [Inline Frame] python39.dll!PyErr_Print() Line 807 C python39.dll!PyRun_InteractiveLoopFlags(_iobuf * fp, const char * filename_str, PyCompilerFlags * flags) Line 137 C python39.dll!PyRun_AnyFileExFlags(_iobuf * fp, const char * filename, int closeit, PyCompilerFlags * flags) Line 81 C python39.dll!pymain_run_stdin(PyConfig * config, PyCompilerFlags * cf) Line 509 C python39.dll!pymain_run_python(int * exitcode) Line 597 C python39.dll!Py_RunMain() Line 675 C python39.dll!Py_Main(int argc, wchar_t * * argv) Line 716 C [External Code] ``` Locals: ``` - m 0x000001fbea75ddb0 {ob_base={ob_refcnt=0 ob_type=0x00007fff5a1e5650 {python39.dll!_typeobject PyCFunction_Type} {...} } ...} PyCFunctionObject * - ob_base {ob_refcnt=0 ob_type=0x00007fff5a1e5650 {python39.dll!_typeobject PyCFunction_Type} {ob_base={ob_base=...} ...} } _object ob_refcnt 0 __int64 - ob_type 0x00007fff5a1e5650 {python39.dll!_typeobject PyCFunction_Type} {ob_base={ob_base={ob_refcnt=23 ob_type=...} ...} ...} _typeobject * + ob_base {ob_base={ob_refcnt=23 ob_type=0x00007fff5a1e7c60 {python39.dll!_typeobject PyType_Type} {ob_base={ob_base=...} ...} } ...} PyVarObject + tp_name 0x00007fff5a16d8a0 "builtin_function_or_method" const char * tp_basicsize 56 __int64 tp_itemsize 0 __int64 tp_dealloc 0x00007fff59e2c260 {python39.dll!meth_dealloc(PyCFunctionObject *)} void(*)(_object *) tp_vectorcall_offset 48 __int64 tp_getattr 0x0000000000000000 _object *(*)(_object *, char *) tp_setattr 0x0000000000000000 int(*)(_object *, char *, _object *) + tp_as_async 0x0000000000000000 <NULL> PyAsyncMethods * tp_repr 0x00007fff59e5c430 {python39.dll!meth_repr(PyCFunctionObject *)} _object *(*)(_object *) + tp_as_number 0x0000000000000000 <NULL> PyNumberMethods * + tp_as_sequence 0x0000000000000000 <NULL> PySequenceMethods * + tp_as_mapping 0x0000000000000000 <NULL> PyMappingMethods * tp_hash 0x00007fff59f44768 {python39.dll!meth_hash(PyCFunctionObject *)} __int64(*)(_object *) tp_call 0x00007fff59e28790 {python39.dll!cfunction_call(_object *, _object *, _object *)} _object *(*)(_object *, _object *, _object *) tp_str 0x00007fff59e5b978 {python39.dll!object_str(_object *)} _object *(*)(_object *) tp_getattro 0x00007fff59e2fc40 {python39.dll!PyObject_GenericGetAttr(_object *, _object *)} _object *(*)(_object *, _object *) tp_setattro 0x00007fff59e92520 {python39.dll!PyObject_GenericSetAttr(_object *, _object *, _object *)} int(*)(_object *, _object *, _object *) + tp_as_buffer 0x0000000000000000 <NULL> PyBufferProcs * tp_flags 808960 unsigned long + tp_doc 0x0000000000000000 <NULL> const char * tp_traverse 0x00007fff59eb0eb0 {python39.dll!meth_traverse(PyCFunctionObject *, int(*)(_object *, void *), void *)} int(*)(_object *, int(*)(_object *, void *), void *) tp_clear 0x0000000000000000 int(*)(_object *) tp_richcompare 0x00007fff59f653a4 {python39.dll!meth_richcompare(_object *, _object *, int)} _object *(*)(_object *, _object *, int) tp_weaklistoffset 40 __int64 tp_iter 0x0000000000000000 _object *(*)(_object *) tp_iternext 0x0000000000000000 _object *(*)(_object *) + tp_methods 0x00007fff5a20dad0 {python39.dll!PyMethodDef meth_methods[2]} {ml_name=0x00007fff5a1673d0 "__reduce__" ...} PyMethodDef * + tp_members 0x00007fff5a20da80 {python39.dll!PyMemberDef meth_members[2]} {name=0x00007fff5a038210 "__module__" ...} PyMemberDef * + tp_getset 0x00007fff5a20d990 {python39.dll!PyGetSetDef meth_getsets[6]} {name=0x00007fff5a038208 "__doc__" get=...} PyGetSetDef * + tp_base 0x00007fff5a1e7e00 {python39.dll!_typeobject PyBaseObject_Type} {ob_base={ob_base={ob_refcnt=10617 ob_type=...} ...} ...} _typeobject * + tp_dict 0x000001fbb3b2a240 {ob_refcnt=1 ob_type=0x00007fff5a1db8b0 {python39.dll!_typeobject PyDict_Type} {ob_base=...} } _object * tp_descr_get 0x0000000000000000 _object *(*)(_object *, _object *, _object *) tp_descr_set 0x0000000000000000 int(*)(_object *, _object *, _object *) tp_dictoffset 0 __int64 tp_init 0x00007fff59e26378 {python39.dll!object_init(_object *, _object *, _object *)} int(*)(_object *, _object *, _object *) tp_alloc 0x00007fff59e98130 {python39.dll!PyType_GenericAlloc(_typeobject *, __int64)} _object *(*)(_typeobject *, __int64) tp_new 0x0000000000000000 _object *(*)(_typeobject *, _object *, _object *) tp_free 0x00007fff59e2c610 {python39.dll!PyObject_GC_Del(void *)} void(*)(void *) tp_is_gc 0x0000000000000000 int(*)(_object *) + tp_bases 0x000001fbb3b04910 {ob_refcnt=1 ob_type=0x00007fff5a1e7920 {python39.dll!_typeobject PyTuple_Type} {...} } _object * + tp_mro 0x000001fbb3b2a400 {ob_refcnt=1 ob_type=0x00007fff5a1e7920 {python39.dll!_typeobject PyTuple_Type} {...} } _object * + tp_cache 0x0000000000000000 <NULL> _object * + tp_subclasses 0x000001fbb3b2a4c0 {ob_refcnt=1 ob_type=0x00007fff5a1db8b0 {python39.dll!_typeobject PyDict_Type} {ob_base=...} } _object * + tp_weaklist 0x000001fbb3b29db0 {ob_refcnt=1 ob_type=0x00007fff5a1e8620 {python39.dll!_typeobject _PyWeakref_RefType} {...} } _object * tp_del 0x0000000000000000 void(*)(_object *) tp_version_tag 40 unsigned int tp_finalize 0x0000000000000000 void(*)(_object *) tp_vectorcall 0x0000000000000000 _object *(*)(_object *, _object * const *, unsigned __int64, _object *) - m_ml 0x000001fbe8ec3fe0 {ml_name=??? ml_meth=??? ml_flags=??? ...} PyMethodDef * ml_name <Unable to read memory> ml_meth <Unable to read memory> ml_flags <Unable to read memory> ml_doc <Unable to read memory> - m_self 0x000001fbea74eed0 {ob_refcnt=2181481948096 ob_type=0x00007fff5a1da1f0 {python39.dll!_typeobject PyCapsule_Type} {...} } _object * ob_refcnt 2181481948096 __int64 - ob_type 0x00007fff5a1da1f0 {python39.dll!_typeobject PyCapsule_Type} {ob_base={ob_base={ob_refcnt=3 ob_type=...} ...} ...} _typeobject * + ob_base {ob_base={ob_refcnt=3 ob_type=0x00007fff5a1e7c60 {python39.dll!_typeobject PyType_Type} {ob_base={ob_base=...} ...} } ...} PyVarObject + tp_name 0x00007fff5a16bb68 "PyCapsule" const char * tp_basicsize 48 __int64 tp_itemsize 0 __int64 tp_dealloc 0x00007fff59f3c880 {python39.dll!capsule_dealloc(_object *)} void(*)(_object *) tp_vectorcall_offset 0 __int64 tp_getattr 0x0000000000000000 _object *(*)(_object *, char *) tp_setattr 0x0000000000000000 int(*)(_object *, char *, _object *) + tp_as_async 0x0000000000000000 <NULL> PyAsyncMethods * tp_repr 0x00007fff5a00093c {python39.dll!capsule_repr(_object *)} _object *(*)(_object *) + tp_as_number 0x0000000000000000 <NULL> PyNumberMethods * + tp_as_sequence 0x0000000000000000 <NULL> PySequenceMethods * + tp_as_mapping 0x0000000000000000 <NULL> PyMappingMethods * tp_hash 0x00007fff59e93c1c {python39.dll!_Py_HashPointer(const void *)} __int64(*)(_object *) tp_call 0x0000000000000000 _object *(*)(_object *, _object *, _object *) tp_str 0x00007fff59e5b978 {python39.dll!object_str(_object *)} _object *(*)(_object *) tp_getattro 0x00007fff59e2fc40 {python39.dll!PyObject_GenericGetAttr(_object *, _object *)} _object *(*)(_object *, _object *) tp_setattro 0x00007fff59e92520 {python39.dll!PyObject_GenericSetAttr(_object *, _object *, _object *)} int(*)(_object *, _object *, _object *) + tp_as_buffer 0x0000000000000000 <NULL> PyBufferProcs * tp_flags 4096 unsigned long + tp_doc 0x00007fff5a122650 "Capsule objects let you wrap a C \"void *\" pointer in a Python\nobject. They're a way of passing data through the Python interpreter\nwithout creating your own custom type.\n\nCapsules are used for commun... const char * tp_traverse 0x0000000000000000 int(*)(_object *, int(*)(_object *, void *), void *) tp_clear 0x0000000000000000 int(*)(_object *) tp_richcompare 0x00007fff59e839c4 {python39.dll!object_richcompare(_object *, _object *, int)} _object *(*)(_object *, _object *, int) tp_weaklistoffset 0 __int64 tp_iter 0x0000000000000000 _object *(*)(_object *) tp_iternext 0x0000000000000000 _object *(*)(_object *) + tp_methods 0x0000000000000000 <NULL> PyMethodDef * + tp_members 0x0000000000000000 <NULL> PyMemberDef * + tp_getset 0x0000000000000000 <NULL> PyGetSetDef * + tp_base 0x00007fff5a1e7e00 {python39.dll!_typeobject PyBaseObject_Type} {ob_base={ob_base={ob_refcnt=10617 ob_type=...} ...} ...} _typeobject * + tp_dict 0x000001fbb3b2d780 {ob_refcnt=1 ob_type=0x00007fff5a1db8b0 {python39.dll!_typeobject PyDict_Type} {ob_base=...} } _object * tp_descr_get 0x0000000000000000 _object *(*)(_object *, _object *, _object *) tp_descr_set 0x0000000000000000 int(*)(_object *, _object *, _object *) tp_dictoffset 0 __int64 tp_init 0x00007fff59e26378 {python39.dll!object_init(_object *, _object *, _object *)} int(*)(_object *, _object *, _object *) tp_alloc 0x00007fff59e98130 {python39.dll!PyType_GenericAlloc(_typeobject *, __int64)} _object *(*)(_typeobject *, __int64) tp_new 0x0000000000000000 _object *(*)(_typeobject *, _object *, _object *) tp_free 0x00007fff59e50cd0 {python39.dll!PyObject_Free(void *)} void(*)(void *) tp_is_gc 0x0000000000000000 int(*)(_object *) + tp_bases 0x000001fbb3b04b50 {ob_refcnt=1 ob_type=0x00007fff5a1e7920 {python39.dll!_typeobject PyTuple_Type} {...} } _object * + tp_mro 0x000001fbb3b2d7c0 {ob_refcnt=1 ob_type=0x00007fff5a1e7920 {python39.dll!_typeobject PyTuple_Type} {...} } _object * + tp_cache 0x0000000000000000 <NULL> _object * + tp_subclasses 0x0000000000000000 <NULL> _object * + tp_weaklist 0x000001fbb3b2f090 {ob_refcnt=1 ob_type=0x00007fff5a1e8620 {python39.dll!_typeobject _PyWeakref_RefType} {...} } _object * tp_del 0x0000000000000000 void(*)(_object *) tp_version_tag 0 unsigned int tp_finalize 0x0000000000000000 void(*)(_object *) tp_vectorcall 0x0000000000000000 _object *(*)(_object *, _object * const *, unsigned __int64, _object *) - m_module 0x000001fbea75e3f0 {ob_refcnt=9 ob_type=0x00007fff5a1e8140 {python39.dll!_typeobject PyUnicode_Type} {...} } _object * ob_refcnt 9 __int64 - ob_type 0x00007fff5a1e8140 {python39.dll!_typeobject PyUnicode_Type} {ob_base={ob_base={ob_refcnt=495 ob_type=...} ...} ...} _typeobject * + ob_base {ob_base={ob_refcnt=495 ob_type=0x00007fff5a1e7c60 {python39.dll!_typeobject PyType_Type} {ob_base={...} ...} } ...} PyVarObject + tp_name 0x00007fff5a036c8c "str" const char * tp_basicsize 80 __int64 tp_itemsize 0 __int64 tp_dealloc 0x00007fff59e2c830 {python39.dll!unicode_dealloc(_object *)} void(*)(_object *) tp_vectorcall_offset 0 __int64 tp_getattr 0x0000000000000000 _object *(*)(_object *, char *) tp_setattr 0x0000000000000000 int(*)(_object *, char *, _object *) + tp_as_async 0x0000000000000000 <NULL> PyAsyncMethods * tp_repr 0x00007fff59ea4cac {python39.dll!unicode_repr(_object *)} _object *(*)(_object *) + tp_as_number 0x00007fff5a20f9f0 {python39.dll!PyNumberMethods unicode_as_number} {nb_add=0x0000000000000000 nb_subtract=...} PyNumberMethods * + tp_as_sequence 0x00007fff5a20f8c0 {python39.dll!PySequenceMethods unicode_as_sequence} {sq_length=0x00007fff59e6c498 {python39.dll!unicode_length(_object *)} ...} PySequenceMethods * + tp_as_mapping 0x00007fff5a20f950 {python39.dll!PyMappingMethods unicode_as_mapping} {mp_length=0x00007fff59e6c498 {python39.dll!unicode_length(_object *)} ...} PyMappingMethods * tp_hash 0x00007fff59e95970 {python39.dll!unicode_hash(_object *)} __int64(*)(_object *) tp_call 0x0000000000000000 _object *(*)(_object *, _object *, _object *) tp_str 0x00007fff59ea68c0 {python39.dll!unicode_str(_object *)} _object *(*)(_object *) tp_getattro 0x00007fff59e2fc40 {python39.dll!PyObject_GenericGetAttr(_object *, _object *)} _object *(*)(_object *, _object *) tp_setattro 0x00007fff59e92520 {python39.dll!PyObject_GenericSetAttr(_object *, _object *, _object *)} int(*)(_object *, _object *, _object *) + tp_as_buffer 0x0000000000000000 <NULL> PyBufferProcs * tp_flags 269227008 unsigned long + tp_doc 0x00007fff5a141740 "str(object='') -> str\nstr(bytes_or_buffer[, encoding[, errors]]) -> str\n\nCreate a new string object from the given object. If encoding or\nerrors is specified, then the object must expose a data buffer... const char * tp_traverse 0x0000000000000000 int(*)(_object *, int(*)(_object *, void *), void *) tp_clear 0x0000000000000000 int(*)(_object *) tp_richcompare 0x00007fff59e828a0 {python39.dll!PyUnicode_RichCompare(_object *, _object *, int)} _object *(*)(_object *, _object *, int) tp_weaklistoffset 0 __int64 tp_iter 0x00007fff59ea7618 {python39.dll!unicode_iter(_object *)} _object *(*)(_object *) tp_iternext 0x0000000000000000 _object *(*)(_object *) + tp_methods 0x00007fff5a20fb70 {python39.dll!PyMethodDef unicode_methods[51]} {ml_name=0x00007fff5a039c58 "encode" ...} PyMethodDef * + tp_members 0x0000000000000000 <NULL> PyMemberDef * + tp_getset 0x0000000000000000 <NULL> PyGetSetDef * + tp_base 0x00007fff5a1e7e00 {python39.dll!_typeobject PyBaseObject_Type} {ob_base={ob_base={ob_refcnt=10617 ob_type=...} ...} ...} _typeobject * + tp_dict 0x000001fbb3b19a40 {ob_refcnt=1 ob_type=0x00007fff5a1db8b0 {python39.dll!_typeobject PyDict_Type} {ob_base=...} } _object * tp_descr_get 0x0000000000000000 _object *(*)(_object *, _object *, _object *) tp_descr_set 0x0000000000000000 int(*)(_object *, _object *, _object *) tp_dictoffset 0 __int64 tp_init 0x00007fff59e26378 {python39.dll!object_init(_object *, _object *, _object *)} int(*)(_object *, _object *, _object *) tp_alloc 0x00007fff59e98130 {python39.dll!PyType_GenericAlloc(_typeobject *, __int64)} _object *(*)(_typeobject *, __int64) tp_new 0x00007fff59e263d8 {python39.dll!unicode_new(_typeobject *, _object *, _object *)} _object *(*)(_typeobject *, _object *, _object *) tp_free 0x00007fff59e50cd0 {python39.dll!PyObject_Free(void *)} void(*)(void *) tp_is_gc 0x0000000000000000 int(*)(_object *) + tp_bases 0x000001fbb3b04610 {ob_refcnt=1 ob_type=0x00007fff5a1e7920 {python39.dll!_typeobject PyTuple_Type} {...} } _object * + tp_mro 0x000001fbb3b19cc0 {ob_refcnt=1 ob_type=0x00007fff5a1e7920 {python39.dll!_typeobject PyTuple_Type} {...} } _object * + tp_cache 0x0000000000000000 <NULL> _object * + tp_subclasses 0x000001fbb94c5f00 {ob_refcnt=1 ob_type=0x00007fff5a1db8b0 {python39.dll!_typeobject PyDict_Type} {ob_base=...} } _object * + tp_weaklist 0x000001fbb3b1fe50 {ob_refcnt=1 ob_type=0x00007fff5a1e8620 {python39.dll!_typeobject _PyWeakref_RefType} {...} } _object * tp_del 0x0000000000000000 void(*)(_object *) tp_version_tag 4 unsigned int tp_finalize 0x0000000000000000 void(*)(_object *) tp_vectorcall 0x0000000000000000 _object *(*)(_object *, _object * const *, unsigned __int64, _object *) - m_weakreflist 0x0000000000000000 <NULL> _object * ob_refcnt <Unable to read memory> ob_type <Unable to read memory> vectorcall 0x0000000000000000 _object *(*)(_object *, _object * const *, unsigned __int64, _object *) ``` ---------- components: Interpreter Core, Windows messages: 373279 nosy: cgohlke, paul.moore, steve.dower, tim.golden, zach.ware priority: normal severity: normal status: open title: Access violation in python39.dll!meth_dealloc on exit versions: Python 3.9 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue41237> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
