[MacPorts] #53816: llvm-3.9 @3.9.1: error: 'future_error' is unavailable: introduced in macOS 10.8 (was: Failed to build llvm-3.9: command execution failed)

[MacPorts]

#53816: llvm-3.9 @3.9.1: error: 'future_error' is unavailable: introduced in macOS
10.8
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  Reporter:  cullub    |      Owner:  jeremyhu
      Type:  defect    |     Status:  assigned
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:
Resolution:            |   Keywords:
      Port:  llvm-3.9  |
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Changes (by ryandesign):

 * status:  new => assigned
 * owner:   => jeremyhu


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Ticket URL: <https://trac.macports.org/ticket/53816#comment:4>
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