[MacPorts] #50448: Change filenames of binary packages built against libc++ on < 10.9

[MacPorts]

#50448: Change filenames of binary packages built against libc++ on < 10.9
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  Reporter:  mojca        |      Owner:  mojca
      Type:  enhancement  |     Status:  assigned
  Priority:  High         |  Milestone:  MacPorts 2.5.0
 Component:  base         |    Version:  2.4.0
Resolution:               |   Keywords:
      Port:               |
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Comment (by RJVB):

 > maintainers lose enthusiasm for trying to support two standard library
 systems.

 I'd use the term "motivation" for myself ;) and more for maintaining
 support for legacy OS versions for which my own OS version isn't
 representative. Supporting 2 different C++ runtimes on those older systems
 only makes things worse.

 There's another solution which requires less hacking: branch off port
 trees for legacy systems, and incite port maintainers to move the latest
 version of their port that support a particular OS X version to the
 corresponding tree.

 So if 10.y were to be the latest version supported officially, users of an
 earlier versions 10.x would have a 10.x tree that they'd install as a
 default tree ahead of the main tree. For example, port:audacity could
 provide 2.1.3 in the 10.6 through 10.8 trees (last version to build
 without C++11) or to use Qt5 as an example in a more general context:
 port:qt5 would be providing Qt 5.8 in the 10.9 tree and 5.10 in the 10.10
 tree (instead of having a bunch of qt5x ports in addition to port:qt5).

 Just mentioning it because I realise this will come with more
 administrative work, but that could in large part be supported by the
 users of those systems. And it's also something that should be required
 only once, in principle.

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Ticket URL: <https://trac.macports.org/ticket/50448#comment:17>
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