[MacPorts] #61477: clang-9.0 fails to build on Big Sur macOS 11.0.1 Xcode 12.2

[MacPorts]

#61477: clang-9.0 fails to build on Big Sur macOS 11.0.1 Xcode 12.2
---------------------------------+--------------------
  Reporter:  jhoyt4              |      Owner:  kencu
      Type:  defect              |     Status:  closed
  Priority:  Normal              |  Milestone:
 Component:  ports               |    Version:
Resolution:  fixed               |   Keywords:
      Port:  clang-9.0 clang-10  |
---------------------------------+--------------------

Comment (by cjones051073):

 Personally I recommend working from a direct git clone of the ports tree
 and not rely on the tarball, which can take a short while to update (and
 seems to be particularly slow right now). i.e.

 {{{
 Oberon-macOS-11 ~/Downloads > tail /opt/local/etc/macports/sources.conf
 # If an "rsync://" URL points to a .tar file, a signed .rmd160 file must
 # exist in the same directory on the server and will be used to verify
 # its integrity.
 #
 # For proper functionality of various resources (port groups, mirror
 # sites, etc.), the primary MacPorts source must always be tagged
 # "[default]", even if switched from the default "rsync://" URL.

 #rsync://rsync.macports.org/macports/release/tarballs/ports.tar [default]
 file:///Users/chris/Projects/MacPorts/ports [default]
 }}}

 where that second path is then a direct git clone of
 https://github.com/macports/macports-ports

 this has numerous benefits, one of which is you are working direct from
 git, so get updates the moment they are committed.

-- 
Ticket URL: <https://trac.macports.org/ticket/61477#comment:38>
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