[MacPorts] #59837: macOS 10.14 SDK does not appear to be installed even though Command Line Tools are installed

[MacPorts]

#59837: macOS 10.14 SDK does not appear to be installed even though Command Line
Tools are installed
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  Reporter:  manulcaux  |      Owner:  (none)
      Type:  defect     |     Status:  new
  Priority:  Normal     |  Milestone:
 Component:  base       |    Version:
Resolution:             |   Keywords:
      Port:             |
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Comment (by manulcaux):

 OK, but I am stuck now.
 I do not plan to upgrade my OS to Catalina before ~ 6 months. I have
 problems to update my ports, maybe because of this SDK problem (ds9 for
 example, there is another ticket open on this), so how should I proceed ?
 Remove completely my port install and restart from scratch ? This would be
 a problem as I have a lot of port installed and used by other software.
 Stay as it is, i.e. do not update my ports until I move to Catalina ? Is
 it viable for 6 more months / I have serious doubts about that...

 Many thanks to give me some advice

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Ticket URL: <https://trac.macports.org/ticket/59837#comment:8>
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