diff --git a/linux/timer-lx.c b/linux/timer-lx.c
index 2e4ae82ba4..4321e46bfa 100644
--- a/linux/timer-lx.c
+++ b/linux/timer-lx.c
@@ -1,6 +1,7 @@
 // Precise timer routines for LINUX  (C) LGB & A'rpi/ASTRAL
 
 #include <unistd.h>
+#include <stdlib.h>
 #include <time.h>
 #include <sys/time.h>
 #include "../config.h"