diff --git a/src/sae.c b/src/sae.c
index dc07db4b..a4150628 100644
--- a/src/sae.c
+++ b/src/sae.c
@@ -24,6 +24,8 @@
 #include <config.h>
 #endif
 
+#include <stdlib.h>
+
 #include <ell/ell.h>
 
 #include "src/missing.h"