[MacPorts] #58978: Unable to Upgrade xar or python27 - Fails to configure

[MacPorts]

#58978: Unable to Upgrade xar or python27 - Fails to configure
---------------------------+--------------------
  Reporter:  RobK88        |      Owner:  (none)
      Type:  defect        |     Status:  new
  Priority:  Normal        |  Milestone:
 Component:  ports         |    Version:  2.5.4
Resolution:                |   Keywords:  Lion
      Port:  xar python27  |
---------------------------+--------------------

Comment (by kencu):

 I had the same problem yesterday. All clangs after about clang-5.0 depend
 on xar, so yep, this broke them all.

 clang 3.7 does not depend on xar, so if you have that, that works.
 Otherwise just your system clang, or clang 3.4, should work. Once xar is
 rebuilt, all your newer clangs will work again. Here's what I did:
 {{{
 sudo port -v upgrade xar configure.compiler=macports-clang-3.7
 }}}

 We'll have to watch for this when we do changes that break xar!

-- 
Ticket URL: <https://trac.macports.org/ticket/58978#comment:1>
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