XMSS-related files get includes.h
diff --git a/xmss_hash.c b/xmss_hash.c
index 963b584..9c42c4f 100644
--- a/xmss_hash.c
+++ b/xmss_hash.c
@@ -5,6 +5,8 @@
 Public domain.
 */
 
+#include "includes.h"
+
 #include "xmss_hash_address.h"
 #include "xmss_commons.h"
 #include "xmss_hash.h"