diff --git a/glib/gmarkup.c b/glib/gmarkup.c
index 945f40695..daa856f46 100644
--- a/glib/gmarkup.c
+++ b/glib/gmarkup.c
@@ -1939,8 +1939,8 @@ g_markup_parse_context_get_element_stack (GMarkupParseContext *context)
 /**
  * g_markup_parse_context_get_position:
  * @context: a #GMarkupParseContext
- * @line_number: (nullable): return location for a line number, or %NULL
- * @char_number: (nullable): return location for a char-on-line number, or %NULL
+ * @line_number: (out) (optional): return location for a line number, or %NULL
+ * @char_number: (out) (optional): return location for a char-on-line number, or %NULL
  *
  * Retrieves the current line number and the number of the character on
  * that line. Intended for use in error messages; there are no strict