diff --git a/hello.c b/hello.c
index ffdf17d6005047040d6d1f0bb6521b7a9b14798d..304528e494897bcc19d300d50c615882f8a4e20e 100644
--- a/hello.c
+++ b/hello.c
@@ -1,4 +1,5 @@
 #include <stdio.h>
+#include <stdlib.h>
 
 int main(int argc, char **argv)
 {