[MacPorts] #68239: Xcode 15 and GCC: linker complains that "duplicate LC_RPATH are deprecated"

[MacPorts]

#68239: Xcode 15 and GCC: linker complains that "duplicate LC_RPATH are deprecated"
----------------------+--------------------
 Reporter:  szhorvat  |      Owner:  (none)
     Type:  defect    |     Status:  new
 Priority:  Normal    |  Milestone:
Component:  ports     |    Version:
 Keywords:            |       Port:  gcc12
----------------------+--------------------
 When linking to shared libraries that were compiled with GCC, e.g. ports
 that need gfortran, the linker included in Xcode 15 issues this warning:

 {{{
 $ cc xx.c -L/opt/local/lib -lopenblas
 ld: warning: duplicate LC_RPATH are deprecated ('/opt/local/lib/libgcc')
 }}}

 Here `openblas` is just an example of such a library, and `xx.c` can be a
 trivial program with an empty `main` function.

 This is well beyond my expertise, but I think it's related to the rpath
 entries here:

 {{{
 $ otool -L /opt/local/lib/libopenblas.1.dylib
 /opt/local/lib/libopenblas.1.dylib:
         /opt/local/lib/libopenblas-r1.dylib (compatibility version 0.0.0,
 current version 0.0.0)
         @rpath/libgfortran.5.dylib (compatibility version 6.0.0, current
 version 6.0.0)
         @rpath/libquadmath.0.dylib (compatibility version 1.0.0, current
 version 1.0.0)
         /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current
 version 1319.100.3)
 }}}

 There's a separate issue that trying to use GCC triggers an assertion
 failure in the linker, but I'm sure you're aware of that (see e.g. this SO
 search:
 https://stackoverflow.com/search?q=file+Relocations.cpp%2C+line+1336 )

-- 
Ticket URL: <https://trac.macports.org/ticket/68239>
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