[MacPorts] #62004: gnuplot fails to build under Catalina because gcc49 is not supported with Xcode 9 or greater

[MacPorts]

#62004: gnuplot fails to build under Catalina because  gcc49 is not supported with
Xcode 9 or greater
------------------------+--------------------
  Reporter:  cwmccurdy  |      Owner:  (none)
      Type:  defect     |     Status:  new
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:
Resolution:             |   Keywords:
      Port:             |
------------------------+--------------------

Comment (by kencu):

 It looks like you've been migrating along for a while now, and finally
 your old variants are no longer supported.

 You have openmpi-default using gcc49 and that is just too out of date to
 keep with now. The current default as of 2021 is gcc10:
 {{{
 $ port info openmpi-default
 openmpi-default @4.0.1_1 (science, parallel, net)
 Variants:             g95, [+]gcc10, gcc44, gcc45, gcc46, gcc47, gcc48,
 gcc49, gcc5, gcc6, gcc7, gcc8, gcc9, gccdevel, universal, valgrind
 }}}

 You are right -- somehow MacPorts should have flagged / fixed / updated /
 sorted this out for you, but -- nobody volunteered to do that work as yet.

 So for now, you should manually do this (or something like it):
 {{{
 sudo port -f uninstall openmpi-default
 sudo port -v install openmpi-default
 }}}
 and then you will get the gcc10 variant. Things should just then work for
 you, unless you have some other gcc49 variants some where that will need a
 similar fix.

 Hope this helps!

-- 
Ticket URL: <https://trac.macports.org/ticket/62004#comment:1>
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