[MacPorts] #69812: /usr/bin/clang++ cannot compile anything when trying to compile as x86_64 on a current arm system against the MacOSX10.13.sdk

[MacPorts]

#69812: /usr/bin/clang++ cannot compile anything when trying to compile as x86_64
on a current arm system against the MacOSX10.13.sdk
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  Reporter:  lukaso  |      Owner:  (none)
      Type:  defect  |     Status:  new
  Priority:  Normal  |  Milestone:
 Component:  ports   |    Version:
Resolution:          |   Keywords:
      Port:          |
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Comment (by ryandesign):

 Replying to [comment:23 lukaso]:
 > The really odd thing is that it works fine on arm64, just not on
 rosetta.

 You're claiming you're able to build an arm64 macOS executable using the
 10.13 SDK? That should be impossible. macOS 11 and its SDK are the first
 to have any arm64 support.

 > The reason is to be able to compile GIMP for x86_64 now that CI
 providers are sunsetting their intel Macs. It's definitely feeling like
 this approach is running against a brick wall, so finding a hosted old mac
 might be the only path. Although, right now, the more likely is that GIMP
 stops supporting Intel Macs.

 There are tons of old Intel Macs available for sale near me that would
 work fine as a 10.13 build server for your needs. I would be surprised if
 you can't find a suitable Mac mini for under $200.

-- 
Ticket URL: <https://trac.macports.org/ticket/69812#comment:27>
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