[MacPorts] #59097: gmp: fails to build with MacPorts 2.6.0 on < 10.9

[MacPorts]

#59097: gmp: fails to build with MacPorts 2.6.0 on < 10.9
---------------------+---------------------------------
  Reporter:  mojca   |      Owner:  MarcusCalhoun-Lopez
      Type:  defect  |     Status:  assigned
  Priority:  High    |  Milestone:
 Component:  ports   |    Version:
Resolution:          |   Keywords:
      Port:  gmp     |
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Comment (by kencu):

 I build it myself with configure.compiler=macports-clang-5.0, and have no
 trouble.

 For some reason Marcus went to some trouble to capture "CC" prior to
 portconfigure.tcl running, and bakes that into the build. So this appears
 to be done on purpose -- but at this moment I don't know why.

 Presumably, we just need to stop doing that, I guess, if the reason is no
 longer too important, whatever it was.

-- 
Ticket URL: <https://trac.macports.org/ticket/59097#comment:2>
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