[MacPorts] #56295: Correctly represent 64-bit platform as x86_64 in ${os.arch} and pre-generated PortIndex

[MacPorts]

#56295: Correctly represent 64-bit platform as x86_64 in ${os.arch} and pre-
generated PortIndex
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  Reporter:  raimue       |      Owner:  (none)
      Type:  enhancement  |     Status:  new
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:
Resolution:               |   Keywords:
      Port:               |
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Comment (by ryandesign):

 Who's to say that how we're currently handling `os.arch` is "incorrect"?
 Up to now, it has always been the case that `os.arch` is "powerpc" on
 32-bit or 64-bit PowerPC systems, and "i386" on 32-bit or 64-bit Intel
 systems. This is neither "correct" nor "incorrect", it's just what we
 decided to do, a long time ago. Hopefully every part of base and most
 ports interpret it that way. Why do we want to go to all the effort of
 changing it and possibly breaking things that rely on the existing
 behavior?

-- 
Ticket URL: <https://trac.macports.org/ticket/56295#comment:1>
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