diff --git a/include/asterisk/strings.h b/include/asterisk/strings.h
index b20a307334..187c3feef1 100755
--- a/include/asterisk/strings.h
+++ b/include/asterisk/strings.h
@@ -13,6 +13,7 @@
 #define _ASTERISK_STRINGS_H
 
 #include <string.h>
+#include <stdarg.h>
 
 #include "asterisk/inline_api.h"
 #include "asterisk/compiler.h"