diff --git a/include/brlib.h b/include/brlib.h
index 6455f8a..7f2cc97 100644
--- a/include/brlib.h
+++ b/include/brlib.h
@@ -18,6 +18,7 @@
 #ifndef _BRLIB_H
 #define _BRLIB_H
 
+#include <stdlib.h>
 #include <stdint.h>
 #include <stdbool.h>
 #include <bits/wordsize.h>                        /* defines __WORDSIZE: 32 or 64 */