diff --git a/window-buffer.c b/window-buffer.c
index f4d4c5f8..014a0b88 100644
--- a/window-buffer.c
+++ b/window-buffer.c
@@ -20,6 +20,7 @@
 
 #include <stdlib.h>
 #include <string.h>
+#include <time.h>
 #include <vis.h>
 
 #include "tmux.h"