[MacPorts] #53348: OpenBLAS*: redo compiler variants

[MacPorts]

#53348: OpenBLAS*: redo compiler variants
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  Reporter:  michaelld                 |      Owner:  NicosPavlov
      Type:  enhancement               |     Status:  new
  Priority:  Normal                    |  Milestone:
 Component:  ports                     |    Version:
Resolution:                            |   Keywords:
      Port:  OpenBlas, OpenBlas-devel  |
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Comment (by NicosPavlov):

 The changes are surely more consistent than what is provided for now,
 thanks for the patch. One thing that may become confusing is the default
 building variants are now +clang +gcc6 +lapack. While I understand the
 logic of it (clang as main compiler, gcc6 for fortran), this may appear as
 a mistake to some users.

 However, I have no real solution there, as making additional variants for
 all possible fortran compiler would be overly complicated in terms of
 choices provided.

 On the same note, building openblas +gcc5 still uses clang as default, and
 just changes the fortran compiler. All this is indicated in the variants
 descriptions, but as it is unusual behaviour, I would expect some
 confusion from users (even though it is probably the best choice in terms
 of binary efficiency).

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Ticket URL: <https://trac.macports.org/ticket/53348#comment:2>
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