diff -r 166784c40be8 Objects/typeobject.c
--- a/Objects/typeobject.c	Sun Jun 05 21:32:45 2016 -0400
+++ b/Objects/typeobject.c	Tue Jun 07 17:16:07 2016 +0800
@@ -4522,8 +4522,10 @@
         descr = PyDescr_NewMember(type, memb);
         if (descr == NULL)
             return -1;
-        if (PyDict_SetItemString(dict, memb->name, descr) < 0)
+        if (PyDict_SetItemString(dict, memb->name, descr) < 0) {
+            Py_DECREF(descr);
             return -1;
+        }
         Py_DECREF(descr);
     }
     return 0;
@@ -4542,8 +4544,10 @@
 
         if (descr == NULL)
             return -1;
-        if (PyDict_SetItemString(dict, gsp->name, descr) < 0)
+        if (PyDict_SetItemString(dict, gsp->name, descr) < 0) {
+            Py_DECREF(descr);
             return -1;
+        }
         Py_DECREF(descr);
     }
     return 0;
@@ -7023,8 +7027,10 @@
             descr = PyDescr_NewWrapper(type, p, *ptr);
             if (descr == NULL)
                 return -1;
-            if (PyDict_SetItem(dict, p->name_strobj, descr) < 0)
+            if (PyDict_SetItem(dict, p->name_strobj, descr) < 0) {
+                Py_DECREF(descr);
                 return -1;
+            }
             Py_DECREF(descr);
         }
     }