diff --git a/src/stc/scintilla/lexers/LexProgress.cxx b/src/stc/scintilla/lexers/LexProgress.cxx
index cede44ebea..1a7c52503b 100644
--- a/src/stc/scintilla/lexers/LexProgress.cxx
+++ b/src/stc/scintilla/lexers/LexProgress.cxx
@@ -25,6 +25,7 @@ Differentiate between labels and variables
 #include <string>
 #include <vector>
 #include <map>
+#include <algorithm>
 
 #include "ILexer.h"
 #include "Scintilla.h"