[MacPorts] #61474: gmp @6.2.0_1: clang: error: invalid version number in 'MACOSX_DEPLOYMENT_TARGET=11.0'

[MacPorts]

#61474: gmp @6.2.0_1: clang: error: invalid version number in
'MACOSX_DEPLOYMENT_TARGET=11.0'
-----------------------+--------------------
  Reporter:  pavibhai  |      Owner:  (none)
      Type:  defect    |     Status:  new
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:  2.6.4
Resolution:            |   Keywords:  bigsur
      Port:            |
-----------------------+--------------------

Comment (by mouse07410):

 > If you open Xcode.app, it will usually offer to upgrape the command line
 tools if they are out of date.

 It looks like Macports is not entirely happy with the command line tools
 installed via/by Xcode. Macports seems to require CLT that get installed
 into {{{/Library/Developer/CommandLineTools}}} by a separate installer
 that one downloads directly from the Apple Developer site.

 I adjust complained about this since time ago in a different ticket.

-- 
Ticket URL: <https://trac.macports.org/ticket/61474#comment:10>
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