[MacPorts] #69317: supported_archs noarch prevents CMake from setting correct flags

[MacPorts]

#69317: supported_archs noarch prevents CMake from setting correct flags
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  Reporter:  barracuda156        |      Owner:  (none)
      Type:  defect              |     Status:  new
  Priority:  Normal              |  Milestone:
 Component:  ports               |    Version:  2.9.1
Resolution:                      |   Keywords:
      Port:  cmake, cmake-devel  |
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Comment (by barracuda156):

 Replying to [comment:1 jmroot]:
 > You're free to set `configure.build_arch` to `$build_arch` (or any other
 value you like) if the default isn't suitable in your "multiple scenarios"
 that involve not building for a native arch.

 Apparently it will not work correctly already when trying to build for
 i386 on x86_64 or universal composed of these two. (So I did not mean
 something necessarily as exotic as building for ppc on x86.)

 And yeah, there are obviously ways to get around that, but arguably it is
 just incorrect behavior that should rather be fixed with CMake PG than
 hacked around.
 It is understandable why it makes sense to mark the installed port as
 `noarch`, it is not clear why flags should be discarded during the build.
 If nothing arch-specific gets installed, then flags make no difference in
 this regard and can be retained, so that tests are not broken. If flags do
 make a difference, then it is not a `noarch` port.

 Or do I miss something about `noarch`?

-- 
Ticket URL: <https://trac.macports.org/ticket/69317#comment:3>
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