Spurious rebuild of Versions.v.i

[Roland McGrath]

> I'm seeing a really strange build failure.  It's too intermittent for me to
> reproduce with debugging.

If you can handle the spew, you could try passing --debug=b to make all the
time so we can examine the messages the next time it bites you.

> Something causes Versions.v.i to be rebuild during processing of a
> subdir; unfortunately, it happens during resolv.

We should figure out and fix the spurious rebuild problem.  But you could
have changed shlib-versions or whatever and then rebuilt in resolv and that
should work right.  Setting CPPFLAGS globally in a subdir is highly
questionable.  For resolv, I think that setting is really only needed for
gethnamadr.c and so it should be CPPFLAGS-gethnamadr.c instead.