diff --git a/include/PresetPreviewPlayHandle.h b/include/PresetPreviewPlayHandle.h
index a95b680abb1..fcdecf6b8bb 100644
--- a/include/PresetPreviewPlayHandle.h
+++ b/include/PresetPreviewPlayHandle.h
@@ -29,6 +29,7 @@
 #include "NotePlayHandle.h"
 
 
+class DataFile;
 class InstrumentTrack;
 class PreviewTrackContainer;
 
diff --git a/include/Song.h b/include/Song.h
index e06658f4ced..c15fed57cd2 100644
--- a/include/Song.h
+++ b/include/Song.h
@@ -29,6 +29,8 @@
 
 #include <QtCore/QSharedMemory>
 #include <QtCore/QVector>
+#include <QHash>
+#include <QString>
 
 #include "TrackContainer.h"
 #include "Controller.h"
diff --git a/src/core/main.cpp b/src/core/main.cpp
index 36fe587574b..08599362ec8 100644
--- a/src/core/main.cpp
+++ b/src/core/main.cpp
@@ -59,6 +59,7 @@
 
 #include "MainApplication.h"
 #include "ConfigManager.h"
+#include "DataFile.h"
 #include "NotePlayHandle.h"
 #include "embed.h"
 #include "Engine.h"