[MacPorts] #64316: gcc9 @9.4.0_1 & gcc10 @10.3.0_1: build failure: Undefined symbols for architecture x86_64

[MacPorts]

#64316: gcc9 @9.4.0_1 & gcc10 @10.3.0_1: build failure: Undefined symbols for
architecture x86_64
-------------------------+--------------------
  Reporter:  i0ntempest  |      Owner:  (none)
      Type:  defect      |     Status:  new
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:  2.7.1
Resolution:              |   Keywords:
      Port:  gcc9 gcc10  |
-------------------------+--------------------

Comment (by kencu):

 MacPorts used to specify a gcc version, like gcc9, to use for various
 ports.

 Then as you upgrade your system and years went by, gcc9 (for example) is
 no longer supported on the newer OS, and the migration would break down.

 The plan for this changed a while back, to try to not specify a definite
 gcc version that would become outdated, but just use the current default
 gcc version whatever it is, which is almost always the supported one, and
 the one you really want to use.

 gcc9 is probably never going to be updated to build on these newer OS
 versions, but the truth is, you don't really want it anyway.

-- 
Ticket URL: <https://trac.macports.org/ticket/64316#comment:8>
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