[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 have the same problem with macOS 10.14+Xcode 11+MacPorts-2.6.0. Simply
 by adding -L/usr/lib to a failing compile/link command allows it to work,
 e.g.:
 {{{
 sudo -u macports /opt/local/bin/gfortran-mp-9 -m128bit-long-double -Wall
 -frecursive -fno-optimize-sibling-calls -m64  -mavx2  -o sblat1 sblat1.o
 ../libopenblas-r1.a -lpthread -lgfortran -lpthread -lgfortran
 ld: library not found for -lSystem
 collect2: error: ld returned 1 exit status
 }}}
 But the following succeeds...
 {{{
 sudo -u macports /opt/local/bin/gfortran-mp-9 -m128bit-long-double -Wall
 -frecursive -fno-optimize-sibling-calls -m64  -mavx2  -o sblat1 sblat1.o
 -L/usr/lib ../libopenblas-r1.a -lpthread -lgfortran -lpthread -lgfortran
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/57994#comment:23>
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