[MacPorts] #61430: Allow x86_64 ports to be used on arm64 hardware via Rosetta 2

[MacPorts]

#61430: Allow x86_64 ports to be used on arm64 hardware via Rosetta 2
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  Reporter:  ryandesign   |      Owner:  (none)
      Type:  enhancement  |     Status:  new
  Priority:  Normal       |  Milestone:
 Component:  base         |    Version:
Resolution:               |   Keywords:
      Port:               |
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Comment (by jmroot):

 Replying to [comment:5 ryandesign]:
 > Replying to [comment:4 jmroot]:
 > > You could certainly set build_arch (or configure.build_arch) to ppc on
 Intel machines with Rosetta,
 >
 > You mean the user on the command line? Or the portfile author in the
 portfile? (And I'm never going to remember the difference between those
 two variables...)

 The user could potentially set either one on the command line, the author
 could set configure.build_arch in the portfile, and the user could set
 build_arch in macports.conf.

 > > but we never auto-demoted the value like we do x86_64 to i386 or ppc64
 to ppc.
 >
 > Do you think that would be easy to add? I thought when I started this
 that I would just be adding another case to the existing ppc-on-i386 case,
 but if we don't have that then I'm not sure where to look.

 Yes, it's pretty straightforward. I think the i386->ppc demotion didn't
 exist just because the code was added during the 64-bit transition. IIRC
 build_arch itself was only added around the time of the Intel transition.

-- 
Ticket URL: <https://trac.macports.org/ticket/61430#comment:6>
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