status report on ports and clang

[Mark Linimon]

As of early December, I have been able to get FreeBSD's secondary ports
cluster (pointyhat-west.isc.FreeBSD.org) to the point where it is able
to more quickly build the entire ports tree with clang as the default
compiler.  You can see the current state here:

  http://wiki.freebsd.org/PortsAndClang

It includes a link to the most recent run on amd64-9:

  http://pointyhat-west.isc.freebsd.org/errorlogs/amd64-errorlogs/e.9-exp-clang.20111218074840.pointyhat-west/index-reason.html

You can see that on that run, 18256 packages were built (out of 22938 in
INDEX), and there were 1208 errors.  For comparison, a recent similar
(but not exact) amd64-9 run on the original pointyhat resulted in 21154
packages and 15 errors.

Under the heading #Known_port_problems, I haved listed the broken ports
that have the largest number of ports depending on them.  IMHO fixing
these should be the highest priority, as they will unblock around 1000
other ports when they are fixed.

Now that we have these results, and will be updating them regularly,
it's less necessary to send PRs noting that port XYZ doesn't build on
clang.  However, PRs with patches are always welcomed :-)

Thanks.

mcl