$OpenBSD: patch-src_library_groupbydialog_h,v 1.2 2020/01/26 17:37:07 rsadowski Exp $

Index: src/library/groupbydialog.h
--- src/library/groupbydialog.h.orig
+++ src/library/groupbydialog.h
@@ -21,6 +21,7 @@
 #include <QDialog>
 
 #include <memory>
+#include <functional>
 
 #include "librarymodel.h"
 
