[MacPorts] #40656: Use -isystem instead of -I in default configure.cppflags

[MacPorts]

#40656: Use -isystem instead of -I in default configure.cppflags
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  Reporter:  ryandesign@…  |      Owner:  macports-tickets@…
      Type:  enhancement   |     Status:  new
  Priority:  Normal        |  Milestone:  MacPorts Future
 Component:  base          |    Version:  2.2.0
Resolution:                |   Keywords:  haspatch
      Port:                |
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Comment (by ryandesign@…):

 I've been using this fix locally on Mountain Lion and Mavericks with no
 problems that I could see.

 However I found a mention that
 [http://public.kitware.com/Bug/view.php?id=10837#c27206 -isystem causes
 problems for C++ code on Tiger]; if I can reproduce that, then maybe we
 have to make this change only on Leopard and later.

-- 
Ticket URL: <https://trac.macports.org/ticket/40656#comment:2>
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