[MacPorts] #59407: libgcc8 not installable and upgrade blocker for macOS 10.15 Catalina

[MacPorts]

#59407: libgcc8 not installable and upgrade blocker for macOS 10.15 Catalina
----------------------+-------------------------------------
  Reporter:  razvand  |      Owner:  (none)
      Type:  defect   |     Status:  new
  Priority:  Normal   |  Milestone:
 Component:  ports    |    Version:  2.6.1
Resolution:           |   Keywords:  libgcc8, macOS Catalina
      Port:  libgcc8  |
----------------------+-------------------------------------

Comment (by cjones051073):

 Another thing you can try is to find any ports using a 'gcc8' variant, and
 then switch this out for a gcc9 one (which invariably there will be). This
 is I think quite likely as variants change over time, but less you
 manually update older ones, such as using older gcc versions, persist
 (port does not automatically handle this well).

 If you followed the migration instructions correctly, just check the list
 of ports you made prior to uninstalling them, identify any using a gcc8
 (or older) variant, and change these to gcc9. In the most part, just
 remove the variant and the default is likely to be gcc9.

 If you failed to follow the migration instructions, try running

 {{{
 port installed | grep gcc
 }}}

 and use the output to identify the ports you need to change the variant
 with.

-- 
Ticket URL: <https://trac.macports.org/ticket/59407#comment:2>
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