diff --git a/src/Buffer.cpp b/src/Buffer.cpp
index ffad9411bf..b9a4f42958 100644
--- a/src/Buffer.cpp
+++ b/src/Buffer.cpp
@@ -42,6 +42,7 @@
 #include "Lexer.h"
 #include "LyXAction.h"
 #include "LyX.h"
+#include "LyXFunc.h"
 #include "LyXRC.h"
 #include "LyXVC.h"
 #include "output_docbook.h"