diff -r f2c7f771bf6a Objects/genobject.c
--- a/Objects/genobject.c	Tue Dec 03 19:17:25 2013 +0100
+++ b/Objects/genobject.c	Wed Dec 04 00:06:21 2013 +0100
@@ -67,6 +67,7 @@ gen_send_ex(PyGenObject *gen, PyObject *
     PyThreadState *tstate = PyThreadState_GET();
     PyFrameObject *f = gen->gi_frame;
     PyObject *result;
+    _Py_IDENTIFIER(clear);
 
     if (gen->gi_running) {
         PyErr_SetString(PyExc_ValueError,
@@ -130,7 +131,7 @@ gen_send_ex(PyGenObject *gen, PyObject *
     if (!result || f->f_stacktop == NULL) {
         /* generator can't be rerun, so release the frame */
         /* first clean reference cycle through stored exception traceback */
-        PyObject *t, *v, *tb;
+        PyObject *t, *v, *tb, *res;
         t = f->f_exc_type;
         v = f->f_exc_value;
         tb = f->f_exc_traceback;
@@ -142,6 +143,14 @@ gen_send_ex(PyGenObject *gen, PyObject *
         Py_XDECREF(tb);
         gen->gi_frame->f_gen = NULL;
         gen->gi_frame = NULL;
+
+        /* explicitly clear local variables of the frame to break
+           reference cycles */
+        assert(!f->f_executing);
+        res = _PyObject_CallMethodId((PyObject*)f, &PyId_clear, NULL);
+        assert(res == Py_None);
+        Py_DECREF(res);
+
         Py_DECREF(f);
     }