diff --git a/http.h b/http.h
index 4eba25b..c62e36d 100644
--- a/http.h
+++ b/http.h
@@ -1,6 +1,7 @@
 #ifndef _HTTP_H_INCLUDED_
 # define _HTTP_H_INCLUDED_
 
+#include <stdarg.h>
 #include "mongoose.h"
 #include "storage.h"
 #include "json.h"
diff --git a/udata.h b/udata.h
index d5f2a9a..780eb86 100644
--- a/udata.h
+++ b/udata.h
@@ -4,6 +4,7 @@
 #include "json.h"
 
 #ifdef WITH_HTTP
+# include <stdarg.h>
 # include "mongoose.h"
 #endif
 #include "gcache.h"