diff --git a/Misc/NEWS.d/next/Core and Builtins/2022-09-18-08-47-40.gh-issue-96821.Co2iOq.rst b/Misc/NEWS.d/next/Core and Builtins/2022-09-18-08-47-40.gh-issue-96821.Co2iOq.rst new file mode 100644 index 0000000000000000000000000000000000000000..4fd0532e827d1862013de117917e077c53a57630 --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2022-09-18-08-47-40.gh-issue-96821.Co2iOq.rst @@ -0,0 +1 @@ +Fix undefined behaviour in ``_testcapimodule.c``. diff --git a/Modules/_testcapimodule.c b/Modules/_testcapimodule.c index 1a3cbe0b212aa693f22357225d9a8948016263a5..43fec8138a0ebc261934942584b92ab46077a115 100644 --- a/Modules/_testcapimodule.c +++ b/Modules/_testcapimodule.c @@ -5576,8 +5576,10 @@ meth_fastcall_keywords(PyObject* self, PyObject* const* args, if (pyargs == NULL) { return NULL; } + assert(args != NULL || nargs == 0); + PyObject* const* args_offset = args == NULL ? NULL : args + nargs; PyObject *pykwargs = PyObject_Vectorcall((PyObject*)&PyDict_Type, - args + nargs, 0, kwargs); + args_offset, 0, kwargs); return Py_BuildValue("NNN", _null_to_none(self), pyargs, pykwargs); }