[MacPorts] #46929: octopus: add mpi.enforce_variant fftw-3

[MacPorts]

#46929: octopus: add mpi.enforce_variant fftw-3
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  Reporter:  takeshi@…  |      Owner:  dstrubbe@…
      Type:  defect     |     Status:  new
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:  2.3.3
Resolution:             |   Keywords:  haspatch
      Port:  octopus    |
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Comment (by sean@…):

 Replying to [comment:1 dstrubbe@…]:
 > The problem is, that is not a default variant, and so the buildbot does
 not have fftw-3 installed with a Fortran variant when building octopus.
 mpi.enforce_variant would not do this either.

 Yes, this is because we can't depend on a variant in  MacPorts.

 > Moreover, it is too restrictive, in that we do not need the same Fortran
 compiler as octopus, just some Fortran variant. Ideas on how to fix this
 situation are certainly welcome.

 This is something @dstrubbe has brought up before but I am very much
 against it. MacPorts has trouble enough as it is to enforce mpi and other
 compiler libraries, much less depending on variants (which is impossible
 currently). Ensuring that we use the same fortran compiler is the only way
 to make ports *reliable* and *reproducible*. Furthermore, @dstrubbe has
 yet to bring up a valid reason for needing a different fortran compiler.
 In the past, I have wanted something similar (gfortran as a standalone
 port) but it is damn near impossible to have this without so much work. It
 is easier and safer to just ensure the same compilers here.

-- 
Ticket URL: <https://trac.macports.org/ticket/46929#comment:2>
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