diff --git a/src/engine/platform/sound/upd1771.cpp b/src/engine/platform/sound/upd1771.cpp
index f79588703..c3d2c073f 100644
--- a/src/engine/platform/sound/upd1771.cpp
+++ b/src/engine/platform/sound/upd1771.cpp
@@ -170,6 +170,7 @@
 **********************************************************************/
 
 #include "upd1771.h"
+#include <string.h>
 
 //#define VERBOSE 1