diff --git a/Lib/python/pycontainer.swg b/Lib/python/pycontainer.swg
index fef4e9b3b..a7cc605ce 100644
--- a/Lib/python/pycontainer.swg
+++ b/Lib/python/pycontainer.swg
@@ -69,8 +69,7 @@ namespace swig {
     static bool back_reference(PyObject* child, PyObject* owner) {
       SwigPyObject* swigThis = SWIG_Python_GetSwigThis(child);
       if (swigThis && (swigThis->own & SWIG_POINTER_OWN) != SWIG_POINTER_OWN) {
-        PyObject_SetAttr(child, container_owner_attribute(), owner);
-        return true;
+        return PyObject_SetAttr(child, container_owner_attribute(), owner) != -1;
       }
       return false;
     }
diff --git a/Lib/python/pyrun.swg b/Lib/python/pyrun.swg
index 445a1e324..82859b887 100644
--- a/Lib/python/pyrun.swg
+++ b/Lib/python/pyrun.swg
@@ -1183,8 +1183,10 @@ SWIG_Python_NewShadowInstance(SwigPyClientData *data, PyObject *swig_this)
 	}
       }
 #else
-      PyObject *key = SWIG_This();
-      PyObject_SetAttr(inst, key, swig_this);
+      if (PyObject_SetAttr(inst, SWIG_This(), swig_this) == -1) {
+        Py_DECREF(inst);
+        inst = 0;
+      }
 #endif
     }
   } else {
@@ -1196,8 +1198,12 @@ SWIG_Python_NewShadowInstance(SwigPyClientData *data, PyObject *swig_this)
         inst = ((PyTypeObject *)data->newargs)->tp_new((PyTypeObject *)data->newargs, empty_args, empty_kwargs);
         Py_DECREF(empty_kwargs);
         if (inst) {
-          PyObject_SetAttr(inst, SWIG_This(), swig_this);
-          Py_TYPE(inst)->tp_flags &= ~Py_TPFLAGS_VALID_VERSION_TAG;
+          if (PyObject_SetAttr(inst, SWIG_This(), swig_this) == -1) {
+            Py_DECREF(inst);
+            inst = 0;
+          } else {
+            Py_TYPE(inst)->tp_flags &= ~Py_TPFLAGS_VALID_VERSION_TAG;
+          }
         }
       }
       Py_DECREF(empty_args);