[MacPorts] #62421: mkvtoolnix 55.0.0: fails to build on macOS 10.14.6

[MacPorts]

#62421: mkvtoolnix 55.0.0: fails to build on macOS 10.14.6
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  Reporter:  mopihopi    |      Owner:  ryandesign
      Type:  defect      |     Status:  assigned
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:
Resolution:              |   Keywords:
      Port:  mkvtoolnix  |
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Comment (by kencu):

 So this is not really an "error" so much as it is a request for some
 MacPorts magic to enable this functionality on 10.14 (and earlier?) where
 it doesn't exist.

 Your best bet is to upgrade your OS to 10.15+. I'm not sure what hardware
 you're on, but there have been some recent software developments that
 allow quite a few older systems to run 10.15+ with modest tweaking. I have
 upgraded four systems to BigSur using that method so far. So Google that.
 If you have any questions you and email me.

 To make software that wants to use the new filesystem features run on
 older os versions whose libc++ does not have these features may or may not
 be possible in the end. We are just exploring that now. A reasonably good
 place to start is to look at the libc++ installation I recently added to
 clang-11, and see how you might (or might not) be able to use that to
 allow this to build on < 10.15.

 It would take some skills -- you have to override the {{{__config}}} file
 and force the libc++ from clang-11, and then there may or may not be ODR
 violations that are show-stoppers. But it will be explored.

 It might be best to start off this process with some simpler port, if we
 can spot one. mkvtoolnix is a bit of a mouthful for a first bite.

-- 
Ticket URL: <https://trac.macports.org/ticket/62421#comment:2>
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