[MacPorts] #61236: OpenBLAS 0.3.10_1 +native Build Fails on MacOS 10.15.6 and Xcode 12.0

[MacPorts]

#61236: OpenBLAS 0.3.10_1 +native Build Fails on MacOS 10.15.6 and Xcode 12.0
-----------------------+-------------------------
  Reporter:  mascguy   |      Owner:  NicosPavlov
      Type:  defect    |     Status:  assigned
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:  2.6.3
Resolution:            |   Keywords:
      Port:  OpenBLAS  |
-----------------------+-------------------------

Comment (by mascguy):

 Folks, thanks for the feedback, as well as the assistance!

 Here's the info requested, along with other (hopefully) useful detail.

 Versions of 'ld64' installed:
 {{{
 $ port -v installed ld64*
   ld64 @3_3 (active) platform='darwin 19' archs='x86_64'
 date='2020-08-17T11:50:51-0400'
   ld64-latest @450.3_0+llvm90 (active) platform='darwin 19' archs='x86_64'
 date='2020-08-17T11:50:47-0400'
 }}}

 Ports selected:
 {{{
 $ port select --summary
 Name        Selected  Options
 ====        ========  =======
 clang       none      mp-clang-10 mp-clang-7.0 mp-clang-8.0 mp-clang-9.0
 none
 cython      none      cython27 cython37 none
 gcc         none      mp-gcc10 none
 llvm        none      mp-llvm-10 mp-llvm-7.0 mp-llvm-8.0 mp-llvm-9.0 none
 maven       none      maven32 none
 mpi         none      openmpi-mp-fortran none
 mysql       none      mariadb-10.5 none
 nosetests   none      nosetests27 nosetests37 none
 perl        none      none
 postgresql  none      postgresql12 none
 pygments    none      py38-pygments none
 pytest      none      pytest37 none
 python      none      python27 python27-apple python37 python38 none
 python2     python27  python27 python27-apple none
 python3     python38  python37 python38 none
 ruby        none      ruby27 none
 }}}

 And finally, I attached a full list of installed ports. Filename: ports-
 installed-10.15.6.txt.gz

 Let me know if there's any additional info I can provide. Ditto for
 additional testing/troubleshooting that would help.

-- 
Ticket URL: <https://trac.macports.org/ticket/61236#comment:7>
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