diff -urN a/hidapi/linux/hid.c b/hidapi/linux/hid.c
--- a/hidapi/linux/hid.c	1985-10-26 17:15:00.000000000 +0900
+++ b/hidapi/linux/hid.c	2019-12-12 11:15:11.164454207 +0900
@@ -24,6 +24,7 @@
 /* C */
 #include <stdio.h>
 #include <string.h>
+#include <stdarg.h>
 #include <stdlib.h>
 #include <locale.h>
 #include <errno.h>