There was a long-standing bug; test.example.com should resolve to
10.7.7.7 to be bug-for-bug identical to BIND (which is the informal
standard for resolving names) since the glue record when given the CNAME
for test.example.com is out of bailiwick.

In more detail, let’s have this when querying the example.com name server:

    test.example.com. CNAME test.example.net.
    test.example.net. A 10.5.5.5

Then let’s have this at the example.net name server:

    test.example.net. A 10.7.7.7

In the past, Deadwood resolved test.example.net as having the IP 10.5.5.5
because there’s a way to accept out-of-bailiwick CNAME glue records
without corrupting the cache, and MaraDNS resolved things this way
back in 2001 because that was how BIND at the time handled it (mind you,
BIND would allow the cache to get corrupted, but it was a long time
ago).

