[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 BKpilot):

 Hello,

 I am getting the same error messages as i0ntempest, i.e., undefined
 symbols in gencondmd.o, when I try to build
 libgcc77.5.0_1.darwin_20.x86_64.tbz2 (MacOS 11.6.2, Xcode 13.2.1 and
 MacPorts 2.7.1. Earlier today I was able to build gcc8, gcc9, gcc10, and
 gcc11 without problems.

 The issue arises when I want to perform "sudo port upgrade outdated". Even
 if I do a "port clean libgcc7" first, the process "upgrade outdated"
 always starts with trying to install libgcc7.

-- 
Ticket URL: <https://trac.macports.org/ticket/64316#comment:2>
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