diff --git a/src/Duration.cpp b/src/Duration.cpp
index 5a8e7eb8b..218e26097 100644
--- a/src/Duration.cpp
+++ b/src/Duration.cpp
@@ -29,6 +29,7 @@
 #include <string>
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <Nibbler.h>
 #include <Lexer.h>
 #include <Duration.h>