diff --git a/Objects/frameobject.c b/Objects/frameobject.c
--- a/Objects/frameobject.c
+++ b/Objects/frameobject.c
@@ -616,9 +616,9 @@ PyFrame_New(PyThreadState *tstate, PyCod
         if (builtins) {
             if (PyModule_Check(builtins)) {
                 builtins = PyModule_GetDict(builtins);
-                assert(!builtins || PyDict_Check(builtins));
+                assert(!builtins || PyDict_Check(builtins) || PyFrozenDict_Check(builtins));
             }
-            else if (!PyDict_Check(builtins))
+            else if (!PyDict_Check(builtins) && !PyFrozenDict_Check(builtins))
                 builtins = NULL;
         }
         if (builtins == NULL) {
@@ -638,7 +638,7 @@ PyFrame_New(PyThreadState *tstate, PyCod
         /* If we share the globals, we share the builtins.
            Save a lookup and a call. */
         builtins = back->f_builtins;
-        assert(builtins != NULL && PyDict_Check(builtins));
+        assert(builtins != NULL && (PyDict_Check(builtins) || PyFrozenDict_Check(builtins)));
         Py_INCREF(builtins);
     }
     if (code->co_zombieframe != NULL) {