change-log-search-tag-name-1 is a compiled Lisp function in `add-log.el'.

(change-log-search-tag-name-1 &optional FROM)

Search for a tag name within subexpression 1 of last match.
Optional argument FROM specifies a buffer position where the tag
name should be located. Return value is a cons whose car is the
string representing the tag and whose cdr is the position where
the tag was found.