1 files changed, 1 insertions, 0 deletions
diff --git a/upb/upb.h b/upb/upb.h
index 153057d..0c49597 100644
--- a/upb/upb.h
+++ b/upb/upb.h
@@ -14,6 +14,7 @@
 #include <stdint.h>
 #include <stdio.h>  // only for size_t.
 #include <assert.h>
+#include <stdarg.h>
 #include "descriptor_const.h"
 #include "atomic.h"