[MacPorts] #59427: mono 6.0.0.319_0 Building Error on 10.15

[MacPorts]

#59427: mono 6.0.0.319_0 Building Error on 10.15
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  Reporter:  fuzunspm  |      Owner:  (none)
      Type:  defect    |     Status:  new
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:  2.6.2
Resolution:            |   Keywords:  catalina
      Port:  mono      |
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Comment (by ryandesign):

 Please attach the main.log file so that we can see what went wrong.

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Ticket URL: <https://trac.macports.org/ticket/59427#comment:2>
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