- char_encode_utf8 (str, XCHAR (base), dst, flags);
- char_encode_utf8 (str, XCHAR (comb), dst, flags);
- return;
+ Lisp_Object comb = Fcar (seq);
+
+ if ( CHARP (comb) )
+ {
+ char_encode_utf8 (str, XCHAR (base), dst, flags);
+ char_encode_utf8 (str, XCHAR (comb), dst, flags);
+ return;
+ }