diff --git a/Python/bytecodes.c b/Python/bytecodes.c
index ec57c07104d239..a2cd51b6f566f5 100644
--- a/Python/bytecodes.c
+++ b/Python/bytecodes.c
@@ -3567,6 +3567,8 @@ dummy_func(
             PyFunctionObject *init = (PyFunctionObject *)cls->_spec_cache.init;
             PyCodeObject *code = (PyCodeObject *)init->func_code;
             DEOPT_IF(code->co_argcount != oparg+1);
+            DEOPT_IF((code->co_flags & (CO_VARKEYWORDS | CO_VARARGS | CO_OPTIMIZED)) != CO_OPTIMIZED);
+            DEOPT_IF(code->co_kwonlyargcount);
             DEOPT_IF(!_PyThreadState_HasStackSpace(tstate, code->co_framesize + _Py_InitCleanup.co_framesize));
             STAT_INC(CALL, hit);
             PyObject *self = _PyType_NewManagedObject(tp);
diff --git a/Python/generated_cases.c.h b/Python/generated_cases.c.h
index b6463b878c1d5e..e17d0b155256f0 100644
--- a/Python/generated_cases.c.h
+++ b/Python/generated_cases.c.h
@@ -996,7 +996,8 @@
             PyFunctionObject *init = (PyFunctionObject *)cls->_spec_cache.init;
             PyCodeObject *code = (PyCodeObject *)init->func_code;
             DEOPT_IF(code->co_argcount != oparg+1, CALL);
-            DEOPT_IF(_Py_Specialize_CheckCode(code) != _Py_Specialize_Ok, CALL);
+            DEOPT_IF((code->co_flags & (CO_VARKEYWORDS | CO_VARARGS | CO_OPTIMIZED)) != CO_OPTIMIZED, CALL);
+            DEOPT_IF(code->co_kwonlyargcount, CALL);
             DEOPT_IF(!_PyThreadState_HasStackSpace(tstate, code->co_framesize + _Py_InitCleanup.co_framesize), CALL);
             STAT_INC(CALL, hit);
             PyObject *self = _PyType_NewManagedObject(tp);