[MacPorts] #59082: openmpi-gcc8 - Port is still broken after rebuilding on Max 10.14 Mojave + Xcode 11

[MacPorts]

#59082: openmpi-gcc8 - Port is still broken after rebuilding  on Max 10.14 Mojave +
Xcode 11
---------------------------+--------------------
  Reporter:  jmbeuken      |      Owner:  (none)
      Type:  defect        |     Status:  new
  Priority:  Normal        |  Milestone:
 Component:  ports         |    Version:  2.6.0
Resolution:                |   Keywords:  mojave
      Port:  openmpi-gcc8  |
---------------------------+--------------------

Comment (by majoc-at-astro):

 Replying to [comment:3 majoc-at-astro]:
 > More details to follow (I'm offsite), but I'll try `port diagnose` on an
 empty build as soon as I'm in contact with our build servers again.

 Once I remembered to add `/opt/local/sbin` to `$PATH`, `port diagnose`
 comes up empty on both test servers.

 --- Ah: now I think I see at least part of the problem (please see massive
 attached logfile):

 {{{
 openmpi-gcc9 is using libstdc++ (this installation is configured to use
 libc++)
 }}}

 Curious, as this is on systems with fresh and otherwise-empty MacPorts
 builds.  Guidance, please, folks.

-- 
Ticket URL: <https://trac.macports.org/ticket/59082#comment:4>
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