[MacPorts] #66103: muniversal portgroup header merging doesn't work on Ventura: diff: unrecognized option `--old-group-format=#ifdef __arm64__

[MacPorts]

#66103: muniversal portgroup header merging doesn't work on Ventura: diff:
unrecognized option `--old-group-format=#ifdef __arm64__
--------------------------------+---------------------
  Reporter:  Morpheus-HH        |      Owner:  (none)
      Type:  defect             |     Status:  new
  Priority:  Normal             |  Milestone:
 Component:  ports              |    Version:  2.8.0
Resolution:                     |   Keywords:  ventura
      Port:  libffi, ossp-uuid  |
--------------------------------+---------------------

Comment (by kencu):

 That happens when you try to install a port as "universal" and it starts
 pulling in deps.

 If the dep has a universal variant, the variant request propagates to the
 the dep, even if the dep is not needed to be universal.

 Ports can indicate they don't supply libraries by setting "installs_libs
 no" in the Portfile, but when macports is running the deps it doesn't know
 what you want exactly, so goes for the universal install of the dep.

 If we make a "diffutils" port that installs "diff" into
 {{{${prefix}/libexec}}}, we can just set it to indicate it has no
 universal variant, and this won't happen.

-- 
Ticket URL: <https://trac.macports.org/ticket/66103#comment:21>
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