Fix a report of conpile-time error.

diff --git a/advent.h b/advent.h
index d6a167b81b0281d9d5955d7373308bcd77ca0d4d..d2b082cbbd785cbdfa880cc5126627c0421cc122 100644 (file)
--- a/advent.h
+++ b/advent.h
@@ -1,6 +1,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdbool.h>
+#include <stdarg.h>
 
 #include "common.h"
 #include "newdb.h"