extern int chars_in_text P_ ((unsigned char *, int));
extern int multibyte_chars_in_text P_ ((unsigned char *, int));
extern int unibyte_char_to_multibyte P_ ((int));
+extern int multibyte_char_to_unibyte P_ ((int, Lisp_Object));
extern Lisp_Object Qcharset;
extern void init_charset_once P_ ((void));
extern void syms_of_charset P_ ((void));