diff --git a/grid.c b/grid.c
index c7ec6752..3eabeeb3 100644
--- a/grid.c
+++ b/grid.c
@@ -1,5 +1,6 @@
 #include "grid.h"
 
+#include <stdlib.h>
 #include <string.h>
 
 #define LOG_MODULE "grid"