diff --git a/lib/database.cc b/lib/database.cc
index bab33341..b3ffd04d 100644
--- a/lib/database.cc
+++ b/lib/database.cc
@@ -1441,6 +1441,8 @@ notmuch_database_upgrade (notmuch_database_t *notmuch,
 	notmuch_message_t *message;
 	char *filename;
 
+	/* XXX: this should use the _st version, but needs an error
+	   path */
 	for (messages = notmuch_query_search_messages (query);
 	     notmuch_messages_valid (messages);
 	     notmuch_messages_move_to_next (messages))
diff --git a/lib/thread.cc b/lib/thread.cc
index 9847cf8b..c8e58c33 100644
--- a/lib/thread.cc
+++ b/lib/thread.cc
@@ -504,6 +504,8 @@ _notmuch_thread_create (void *ctx,
      * oldest or newest subject is desired. */
     notmuch_query_set_sort (thread_id_query, NOTMUCH_SORT_OLDEST_FIRST);
 
+    /* XXX: this should use the _st version, but it needs an error path
+     */
     for (messages = notmuch_query_search_messages (thread_id_query);
 	 notmuch_messages_valid (messages);
 	 notmuch_messages_move_to_next (messages))