diff --git a/libntfs/tree.c b/libntfs/tree.c
index 0e11284e..0945d0b8 100644
--- a/libntfs/tree.c
+++ b/libntfs/tree.c
@@ -28,6 +28,9 @@
 #ifdef HAVE_STDLIB_H
 #include <stdlib.h>
 #endif
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
 
 #include "volume.h"
 #include "dir.h"