diff --git a/include/podio/DataSource.h b/include/podio/DataSource.h
index 6a3c5fde4..d6a2c49e3 100644
--- a/include/podio/DataSource.h
+++ b/include/podio/DataSource.h
@@ -1,5 +1,5 @@
-#ifndef PODIO_DATASOURCE_H__
-#define PODIO_DATASOURCE_H__
+#ifndef PODIO_DATASOURCE_H
+#define PODIO_DATASOURCE_H
 
 // Podio
 #include <podio/CollectionBase.h>
@@ -176,4 +176,4 @@ ROOT::RDataFrame CreateDataFrame(const std::vector<std::string>& filePathList);
 ROOT::RDataFrame CreateDataFrame(const std::string& filePath);
 } // namespace podio
 
-#endif /* PODIO_DATASOURCE_H__ */
+#endif /* PODIO_DATASOURCE_H */
diff --git a/tests/root_io/read_with_rdatasource_root.cpp b/tests/root_io/read_with_rdatasource_root.cpp
index cdcd691b5..29bad4319 100644
--- a/tests/root_io/read_with_rdatasource_root.cpp
+++ b/tests/root_io/read_with_rdatasource_root.cpp
@@ -1,5 +1,5 @@
-#include "podio/DataSource.h"
 #include "datamodel/ExampleClusterCollection.h"
+#include "podio/DataSource.h"
 
 #include <iostream>
 #include <string>