How to test a patch in resolv/?

[Stan Shebs]

Last week at Google, getaddrinfo() blew up in an attention-getting way,
apparently due to an innocuous internal server change triggering BZ 16754
(the library version we're using derives from 2.19).

So while there is a patch for this bug, and it even applies cleanly to our
version, I'm wondering how to write a test that demonstrates it's an actual
fix, without depending on masses of internal Google configuration. It seems
like one ought to be able to build a little mock DNS server, but I don't see
that anyone has done that to date, and maybe there is some better way
to do a unit test.

Does anybody have any ideas or suggestions? Thanks!

Stan