[MacPorts] #57448: i686-w64-mingw32-winpthreads and x86_64-w64-mingw32-winpthreads : linker does not accept syslibroot

[MacPorts]

#57448: i686-w64-mingw32-winpthreads and  x86_64-w64-mingw32-winpthreads : linker
does not accept syslibroot
-------------------------------------------------+-------------------------
  Reporter:  eviltwinskippy                      |      Owner:  mojca
      Type:  defect                              |     Status:  assigned
  Priority:  Normal                              |  Milestone:
 Component:  ports                               |    Version:  2.5.4
Resolution:                                      |   Keywords:  mingw
      Port:  i686-w64-mingw32-winpthreads        |  mingw-w64
  x86_64-w64-mingw32-winpthreads                 |
-------------------------------------------------+-------------------------

Comment (by mojca):

 I suspect this is specific to > 10.13 and the way how location of files
 changed on the OS.

 I'll need more time investigating this, but `-syslibroot
 /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk`
 sounds wrong in any case. First of all, I would not be surprised if the
 linker used for cross-compiler doesn't support `-syslibroot`, but more
 importantly, the headers needed for cross-compiler are definitely not
 present in MacOSX10.14.sdk. I would start with figuring out how that
 `-syslibroot` got to the command line in the first place, and try to
 figure out if I can disable / remove that flag from the Portfile.

 I would imagine that other cross-compilers would be bitten by similar
 issues? (OK, the compiler itself apparently gets compiled just fine, it's
 further additions that have troubles. It could also be that the cross-
 compiler PortGroup in fact disables some bits and pieces which I forgot to
 disable in `mingw-w64.)

-- 
Ticket URL: <https://trac.macports.org/ticket/57448#comment:8>
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