4768. [func] By default, memory is no longer filled with tag values
when it is allocated or freed; this improves
performance but makes debugging of certain memory
issues more difficult. "named -M fill" turns memory
filling back on. (Building "configure
--enable-developer", turns memory fill on by
default again; it can then be disabled with
"named -M nofill".) [RT #45123]
4674. [func] "dig +sigchase", and related options "+topdown" and
"+trusted-keys", have been removed. Use "delv" for
queries with DNSSEC validation. [RT #42793]
