diff --git a/deno2/main.cc b/deno2/main.cc
index 820f15a095..2c0b1b2983 100644
--- a/deno2/main.cc
+++ b/deno2/main.cc
@@ -2,6 +2,7 @@
 // All rights reserved. MIT License.
 #include <assert.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #include "include/deno.h"