diff --git a/src/corelib/serialization/qxmlstream.h b/src/corelib/serialization/qxmlstream.h
index 8a12c6d6115..670d88f3f05 100644
--- a/src/corelib/serialization/qxmlstream.h
+++ b/src/corelib/serialization/qxmlstream.h
@@ -36,7 +36,7 @@ public:
 };
 
 }
-Q_DECLARE_SHARED(QtPrivate::QXmlString)
+Q_DECLARE_SHARED_NS_EXT(QtPrivate, QXmlString)
 
 
 class QXmlStreamReaderPrivate;