diff --git a/DDG4/edm4hep/Geant4Output2EDM4hep.cpp b/DDG4/edm4hep/Geant4Output2EDM4hep.cpp
index b007e76a350ad558fe7a34a296dabd756c75e586..335392f8ff0899f02d5f6ae2b315a8077d32fb2c 100644
--- a/DDG4/edm4hep/Geant4Output2EDM4hep.cpp
+++ b/DDG4/edm4hep/Geant4Output2EDM4hep.cpp
@@ -49,7 +49,7 @@ namespace dd4hep {
       using writer_t = podio::ROOTFrameWriter;
       using stringmap_t = std::map< std::string, std::string >;
       using trackermap_t = std::map< std::string, edm4hep::SimTrackerHitCollection >;
-      using calorimeterpair_t std::pair< edm4hep::SimCalorimeterHitCollection, edm4hep::CaloHitContributionCollection >;
+      using calorimeterpair_t = std::pair< edm4hep::SimCalorimeterHitCollection, edm4hep::CaloHitContributionCollection >;
       using calorimetermap_t = std::map< std::string, calorimeterpair_t >;
       std::unique_ptr<writer_t>     m_file  { };
       podio::Frame                  m_frame { };