diff --git a/fs/udf/udfdecl.h b/fs/udf/udfdecl.h
index 6995ab1..74d58c0 100644
--- a/fs/udf/udfdecl.h
+++ b/fs/udf/udfdecl.h
@@ -111,6 +111,8 @@
 };
 
 /* super.c */
+
+__attribute__((format(printf, 3, 4)))
 extern void udf_warning(struct super_block *, const char *, const char *, ...);
 static inline void udf_updated_lvid(struct super_block *sb)
 {