void narrow_line_number_cache (struct buffer *);
void insert_invalidate_line_number_cache (struct buffer *, Bufpos,
void narrow_line_number_cache (struct buffer *);
void insert_invalidate_line_number_cache (struct buffer *, Bufpos,
void delete_invalidate_line_number_cache (struct buffer *, Bufpos, Bufpos);
EMACS_INT buffer_line_number (struct buffer *, Bufpos, int);
void delete_invalidate_line_number_cache (struct buffer *, Bufpos, Bufpos);
EMACS_INT buffer_line_number (struct buffer *, Bufpos, int);