1 files changed, 1 insertions, 0 deletions
diff --git a/utf8.h b/utf8.h
index 32a7bfb987..65d0e42b96 100644
--- a/utf8.h
+++ b/utf8.h
@@ -10,6 +10,7 @@ int utf8_strwidth(const char *string);
 int is_utf8(const char *text);
 int is_encoding_utf8(const char *name);
 int same_encoding(const char *, const char *);
+__attribute__((format (printf, 2, 3)))
 int utf8_fprintf(FILE *, const char *, ...);
 
 void strbuf_add_wrapped_text(struct strbuf *buf,