diff --git a/gtk2_ardour/loudness_dialog.h b/gtk2_ardour/loudness_dialog.h
index fd7e9c8700..65c4109e6d 100644
--- a/gtk2_ardour/loudness_dialog.h
+++ b/gtk2_ardour/loudness_dialog.h
@@ -36,7 +36,7 @@
 #include "loudness_settings.h"
 
 namespace ARDOUR {
-	class TimelineRange;
+	struct TimelineRange;
 	class ExportAnalysis;
 	class ExportStatus;
 	class PluginInsert;
diff --git a/libs/ardour/ardour/utils.h b/libs/ardour/ardour/utils.h
index b7e6b10301..1c1c8ec6b5 100644
--- a/libs/ardour/ardour/utils.h
+++ b/libs/ardour/ardour/utils.h
@@ -54,7 +54,8 @@ class Route;
 class Track;
 class Region;
 class Source;
-class TimelineRange;
+
+struct TimelineRange;
 
 LIBARDOUR_API std::string legalize_for_path (const std::string& str);
 LIBARDOUR_API std::string legalize_for_universal_path (const std::string& str);