[MacPorts] #65269: mpi portgroup fails to select a C compiler variant if the default is disallowed

[MacPorts]

#65269: mpi portgroup fails to select a C compiler variant if the default is
disallowed
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  Reporter:  jmroot  |      Owner:  mascguy
      Type:  defect  |     Status:  assigned
  Priority:  Normal  |  Milestone:
 Component:  ports   |    Version:
Resolution:          |   Keywords:
      Port:          |
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Comment (by mascguy):

 Replying to [comment:7 jmroot]:
 > In this specific instance, yes, but it will just come back next time a
 new clang version is added. The portgroup really needs to do something
 sensible when configure.compiler is set to a compiler it doesn't know
 about.

 My thought is that we should coordinate when making a new Clang version
 the default. In particular, we should first add new MPI subports to
 `openmpi` and `mpich`, and vet those out.

 Once we're confident that all is well, then - and only then - update the
 default Clang.

 Thoughts?

-- 
Ticket URL: <https://trac.macports.org/ticket/65269#comment:8>
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