diff --git a/Python/ceval.c b/Python/ceval.c
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -5342,8 +5342,10 @@
             PyObject **freevars = (f->f_localsplus +
                                    f->f_code->co_nlocals);
             PyObject *c = freevars[oparg];
-            if (PyCell_GET(c) == v)
-                PyCell_Set(c, NULL);
+            if (PyCell_GET(c) ==  v) {
+                PyCell_SET(c, NULL);
+                Py_DECREF(v);
+            }
             break;
         }
         case STORE_NAME: