[MacPorts] #59113: gcc: cannot find systems headers with Xcode 11

[MacPorts]

#59113: gcc: cannot find systems headers with Xcode 11
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  Reporter:  abyrvalk        |      Owner:  (none)
      Type:  defect          |     Status:  new
  Priority:  Normal          |  Milestone:
 Component:  ports           |    Version:
Resolution:                  |   Keywords:
      Port:  gcc7 gcc8 gcc9  |
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Comment (by mouse07410):

 I found https://trac.macports.org/ticket/59113#comment:18 (particularly
 item 2) much easier to follow, with one exception of the change I
 mentioned.

 AFAICT, https://trac.macports.org/ticket/59113#comment:14 only makes sense
 if you still have Xcode-10 and are only considering upgrading to Xcode-11.
 In my case Xcode-11 was dropped onto my computers by IT replacing
 Xcode-10, so I had to figure how to retrieve the situation when Xcode-10
 is gone and Xcode-11 is the only one installed.

 https://trac.macports.org/ticket/59113#comment:18 item 2 offers the
 lowest-expenditure workaround, at the cost of one extra manual operation
 (symlinking).

-- 
Ticket URL: <https://trac.macports.org/ticket/59113#comment:22>
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