diff --git a/include/xalloc.h b/include/xalloc.h
index 27efa30c5..841333c30 100644
--- a/include/xalloc.h
+++ b/include/xalloc.h
@@ -12,6 +12,7 @@
 
 #include <stdlib.h>
 #include <err.h>
+#include <string.h>
 
 #include "c.h"