[MacPorts] #60001: libgcc7 fails to build on 10.15

[MacPorts]

#60001: libgcc7 fails to build on 10.15
------------------------+--------------------
  Reporter:  ffm-fg     |      Owner:  (none)
      Type:  defect     |     Status:  closed
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:
Resolution:  duplicate  |   Keywords:
      Port:  libgcc7    |
------------------------+--------------------

Comment (by kencu):

 part of your issue is the `ld64` installation, I think. You should not be
 seeing this error:
 {{{
 ld: unexpected token: !tapi-tbd-v3 file
 }}}
 so please try this:
 {{{
 sudo port -f uninstall ld64
 sudo port -v install ld64
 }}}
 and that should get you `ld64 +ld64_xcode` which is what you need on
 Catalina at present.

 Then retry your build, and report back errors.

-- 
Ticket URL: <https://trac.macports.org/ticket/60001#comment:2>
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