diff --git a/Modules/_struct.c b/Modules/_struct.c
index 6149964..8e5420c 100644
--- a/Modules/_struct.c
+++ b/Modules/_struct.c
@@ -1471,7 +1471,7 @@
 		return -1;
 
 	Py_INCREF(o_format);
-	Py_XDECREF(soself->s_format);
+	Py_CLEAR(soself->s_format);
 	soself->s_format = o_format;
 
 	ret = prepare_s(soself);
diff --git a/Modules/cStringIO.c b/Modules/cStringIO.c
index 3529047..139a4a8 100644
--- a/Modules/cStringIO.c
+++ b/Modules/cStringIO.c
@@ -575,8 +575,7 @@
 
 static PyObject *
 I_close(Iobject *self, PyObject *unused) {
-        Py_XDECREF(self->pbuf);
-        self->pbuf = NULL;
+        Py_CLEAR(self->pbuf);
         self->buf = NULL;
 
         self->pos = self->string_size = 0;