diff --git a/common/qnaturalsorting.h b/common/qnaturalsorting.h
index 9a84f96a..614e419e 100644
--- a/common/qnaturalsorting.h
+++ b/common/qnaturalsorting.h
@@ -7,6 +7,7 @@
 #include <QFileInfo>
 #include "library_item.h"
 
+int naturalCompare(const QString &s1, const QString &s2,  Qt::CaseSensitivity caseSensitivity);
 bool naturalSortLessThanCS( const QString &left, const QString &right );
 bool naturalSortLessThanCI( const QString &left, const QString &right );
 bool naturalSortLessThanCIFileInfo(const QFileInfo & left,const QFileInfo & right);