[MacPorts] #57994: OpenBLAS compilation fails on MacBook Pro MacOS 10.14

[MacPorts]

#57994: OpenBLAS compilation fails on MacBook Pro MacOS 10.14
-------------------------+-------------------------
  Reporter:  Tim-at-AST  |      Owner:  NicosPavlov
      Type:  defect      |     Status:  reopened
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:  2.5.4
Resolution:              |   Keywords:
      Port:  OpenBLAS    |
-------------------------+-------------------------

Comment (by JohnPritchard):

 I seem to have solved the problem (at least for OpenBLAS and py-numpy) by
 rebuilding/installing gcc9 (which provides gfortran needed by OpenBLAS)
 from source.
 {{{
 sudo port uninstall gcc9
 sudo port clean gcc9
 sudo port -s install gcc9
 sudo port -s install OpenBLAS
 }}}
 So it seems that there is some sort of incompatibility between gcc9 (and
 probably many other) binaries built under Xcode-10 which are then run in
 an Xcode-11 environment.

 It would probably be safest to rebuild/install from source ALL ports in
 such an installation, well that's what I'll probably have my computer
 doing over the weekend...

 Hope this was helpful.

-- 
Ticket URL: <https://trac.macports.org/ticket/57994#comment:24>
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