diff --git a/src/lisp/x86-arch.c b/src/lisp/x86-arch.c
index 6624ce63da3518c157d96b7121309abab2bd7663..4a494d1c16a766d50ef62c3cadb734161cd0a39d 100644
--- a/src/lisp/x86-arch.c
+++ b/src/lisp/x86-arch.c
@@ -7,6 +7,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 
 #include "lisp.h"
 #include "globals.h"