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--- a/src/qtgui/recoll.h
+++ b/src/qtgui/recoll.h
@@ -21,6 +21,7 @@
 
 #include "rclconfig.h"
 #include "rcldb.h"
+#include "rclutil.h"
 #include "ptmutex.h"
 
 #include <QString>