1 files changed, 46 insertions, 0 deletions
diff --git a/Python/ceval.c b/Python/ceval.c
index 5d5221b2e4..958689debc 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -212,6 +212,9 @@ static _PyInterpreterFrame *
 _PyEvalFramePushAndInit(PyThreadState *tstate, PyFunctionObject *func,
                         PyObject *locals, PyObject* const* args,
                         size_t argcount, PyObject *kwnames);
+static  _PyInterpreterFrame *
+_PyEvalFramePushAndInit_Ex(PyThreadState *tstate, PyFunctionObject *func,
+    PyObject *locals, Py_ssize_t nargs, PyObject *callargs, PyObject *kwargs);
 static void
 _PyEvalFrameClearAndPop(PyThreadState *tstate, _PyInterpreterFrame *frame);
 
@@ -1501,6 +1504,49 @@ fail:
     return NULL;
 }
 
+/* Same as _PyEvalFramePushAndInit but takes an args tuple and kwargs dict.
+   Steals references to func, callargs and kwargs.
+*/
+static _PyInterpreterFrame *
+_PyEvalFramePushAndInit_Ex(PyThreadState *tstate, PyFunctionObject *func,
+    PyObject *locals, Py_ssize_t nargs, PyObject *callargs, PyObject *kwargs)
+{
+    bool has_dict = (kwargs != NULL && PyDict_GET_SIZE(kwargs) > 0);
+    PyObject *kwnames = NULL;
+    PyObject *const *newargs;
+    if (has_dict) {
+        newargs = _PyStack_UnpackDict(tstate, _PyTuple_ITEMS(callargs), nargs, kwargs, &kwnames);
+        if (newargs == NULL) {
+            Py_DECREF(func);
+            goto error;
+        }
+    }
+    else {
+        newargs = &PyTuple_GET_ITEM(callargs, 0);
+        /* We need to incref all our args since the new frame steals the references. */
+        for (Py_ssize_t i = 0; i < nargs; ++i) {
+            Py_INCREF(PyTuple_GET_ITEM(callargs, i));
+        }
+    }
+    _PyInterpreterFrame *new_frame = _PyEvalFramePushAndInit(
+        tstate, (PyFunctionObject *)func, locals,
+        newargs, nargs, kwnames
+    );
+    if (has_dict) {
+        _PyStack_UnpackDict_FreeNoDecRef(newargs, kwnames);
+    }
+    /* No need to decref func here because the reference has been stolen by
+       _PyEvalFramePushAndInit.
+    */
+    Py_DECREF(callargs);
+    Py_XDECREF(kwargs);
+    return new_frame;
+error:
+    Py_DECREF(callargs);
+    Py_XDECREF(kwargs);
+    return NULL;
+}
+
 PyObject *
 _PyEval_Vector(PyThreadState *tstate, PyFunctionObject *func,
                PyObject *locals,