diff --git a/xs/src/libslic3r/Config.cpp b/xs/src/libslic3r/Config.cpp
index 36332c789..899936334 100644
--- a/xs/src/libslic3r/Config.cpp
+++ b/xs/src/libslic3r/Config.cpp
@@ -12,6 +12,7 @@
 #include <boost/property_tree/ptree.hpp>
 #include <boost/algorithm/string.hpp>
 #include <boost/lexical_cast.hpp>
+#include <string.h>
 
 #if defined(_WIN32) && !defined(setenv) && defined(_putenv_s)
 #define setenv(k, v, o) _putenv_s(k, v)