diff --git a/src/rcldb/synfamily.cpp b/src/rcldb/synfamily.cpp
index 67e8d0d4..a23bf3f7 100644
--- a/src/rcldb/synfamily.cpp
+++ b/src/rcldb/synfamily.cpp
@@ -23,6 +23,7 @@
 #include "synfamily.h"
 
 #include <iostream>
+#include <algorithm>
 
 using namespace std;