diff --git a/src/xselect.c b/src/xselect.c
index 15a4c283b8b..969fd4e4148 100644
--- a/src/xselect.c
+++ b/src/xselect.c
@@ -1620,7 +1620,7 @@ lisp_data_to_selection_data (display, obj,
       num = ((*size_ret <= 1	/* Check the possibility of short cut.  */
 	      || NILP (buffer_defaults.enable_multibyte_characters))
 	     ? 0
-	     : find_charset_in_str (*data_ret, *size_ret, charsets, Qnil));
+	     : find_charset_in_str (*data_ret, *size_ret, charsets, Qnil, 1));
 
       if (!num || (num == 1 && charsets[CHARSET_ASCII]))
 	{