diff --git a/misc/rtstat.c b/misc/rtstat.c
index feed6cf2..2451fdab 100644
--- a/misc/rtstat.c
+++ b/misc/rtstat.c
@@ -15,6 +15,7 @@
 
 #include <stdio.h>
 #include <unistd.h>
+#include <stdlib.h>
 #include <getopt.h>
 
 #define VERSION "0.33 010829"