diff --git a/gdbsupport/ChangeLog b/gdbsupport/ChangeLog
index b2fbc56b1b..4db482b151 100644
--- a/gdbsupport/ChangeLog
+++ b/gdbsupport/ChangeLog
@@ -1,3 +1,8 @@
+2020-06-27  Simon Marchi  <simon.marchi@efficios.com>
+
+	* tdesc.h (class print_xml_feature) <add_line>: Add
+	ATTRIBUTE_PRINTF.
+
 2020-06-23  Andrew Burgess  <andrew.burgess@embecosm.com>
 
 	* tdesc.cc (print_xml_feature::visit_pre): Use add_line to add
diff --git a/gdbsupport/tdesc.h b/gdbsupport/tdesc.h
index 73caf24536..456e8e070b 100644
--- a/gdbsupport/tdesc.h
+++ b/gdbsupport/tdesc.h
@@ -438,7 +438,7 @@ private:
      functions appends a newline, so don't include one in the strings being
      passed.  */
   void add_line (const std::string &str);
-  void add_line (const char *fmt, ...);
+  void add_line (const char *fmt, ...) ATTRIBUTE_PRINTF (2, 3);
 
   /* The buffer we are writing too.  */
   std::string *m_buffer;