mbstring unused internal functions

Hello. Looking through the source code of the mbstring.c file I found a lot of unused internal functions. It seems that this is just a bunch of old junk. Examples: MBSTRING_API size_t php_mb_mbchar_bytes_ex(const char *s, const mbfl_encoding *enc) MBSTRING_API size_t php_mb_mbchar_bytes(const char *s) MBSTRING_API char *php_mb_safe_strrchr(const char *s, unsigned int c, size_t nbytes) MBSTRING_API char *php_mb_safe_strrchr_ex(const char *s, unsigned int c, size_t nbytes, const mbfl_encoding *enc)