[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 ryandesign):

 Replying to [ticket:61474 pavibhai]:
 > {{{
 > ll /Library/Developer/CommandLineTools/SDKs/
 >
 > lrwxr-xr-x  1 root  wheel   15 Oct 13  2019 MacOSX.sdk ->
 MacOSX10.15.sdk
 > drwxr-xr-x  7 root  wheel  224 Jul 15  2019 MacOSX10.14.sdk
 > drwxr-xr-x  8 root  wheel  256 Aug 29  2019 MacOSX10.15.sdk
 > }}}

 That confirms that your command line tools are too old for Big Sur and
 need to be updated.

-- 
Ticket URL: <https://trac.macports.org/ticket/61474#comment:4>
MacPorts <https://www.macports.org/>
Ports system for macOS