diff --git a/LEGO1/mxcore.h b/LEGO1/mxcore.h
index c3e944a7..caf8b17b 100644
--- a/LEGO1/mxcore.h
+++ b/LEGO1/mxcore.h
@@ -30,7 +30,7 @@ class MxCore
     return !strcmp(name, MxCore::ClassName());
   }
 
-  inline GetId()
+  inline int GetId()
   {
     return m_id;
   }