diff --git a/project/src/ExternalInterface.cpp b/project/src/ExternalInterface.cpp
index bf746d0fa..989d1e798 100644
--- a/project/src/ExternalInterface.cpp
+++ b/project/src/ExternalInterface.cpp
@@ -54,6 +54,7 @@
 #endif
 
 #include <cstdlib>
+#include <cstring>
 
 DEFINE_KIND (k_finalizer);