If Clang 3.7 is installed, why do ports install 3.6?

[Chris H]

Greetings, all.
On a fresh install of -CURRENT with a new world, and kernel on
an i386. I just performed a make config-recursive in x11/xorg-minimal,
and to my dismay, I'm greeted with a dialog for clang-3.6 options,
as well as for llvm.
world already built clang-3.7, as well as a more recent version of
llvm than is called for from the ports dialog. Can I mark lang/clang*
forbidden, or somehow insist the port chooses the clang version
installed from base?

This is not only an i386, but it also has fairly low resources,
and clang could take many hours to make. Which seems *quite*
silly, since the task is redundant.

Thanks!

--Chris

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