[MacPorts] #58378: Qt5 CMake component fails under Xcode-10.2

[MacPorts]

#58378: Qt5 CMake component fails under Xcode-10.2
-------------------------+---------------------------------
  Reporter:  mouse07410  |      Owner:  MarcusCalhoun-Lopez
      Type:  defect      |     Status:  assigned
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:
Resolution:              |   Keywords:
      Port:  qt5-qtbase  |
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Comment (by chrstphrchvz):

 @mouse07410, in general, improvements to MacPorts will have much better
 luck of being handled quickly if they are submitted as
 [https://github.com/macports/macports-ports/pulls pull requests on
 GitHub].

 I don't think MacPorts can guarantee that the location of Xcode.app will
 be /Applications/Xcode.app, so I don't think paths to its contents can be
 hardcoded exactly as suggested. Maybe MacPorts has a variable for this
 purpose, and/or there is a path that will be guaranteed to exist
 regardless of where Xcode.app is (maybe something like
 /Library/Developer/CommandLineTools/SDKs/…).

-- 
Ticket URL: <https://trac.macports.org/ticket/58378#comment:7>
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