[MacPorts] #57335: port:cmake : why the libcxx depspec on systems that have the system libc++?

[MacPorts]

#57335: port:cmake : why the libcxx depspec on systems that have the system libc++?
--------------------------+--------------------
  Reporter:  RJVB         |      Owner:  (none)
      Type:  enhancement  |     Status:  new
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:
Resolution:               |   Keywords:
      Port:  cmake        |
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Comment (by RJVB):

 So assuming libcxx should indeed NOT be installed on 10.5 and earlier
 (why?), the expression would be easier (to understand) as

 {{{
 if {(${os.platform} eq "darwin" && ${os.major} == 10) && ${build_arch} ne
 "ppc" && ${build_arch} ne "ppc64"} {
 }}}

 but in either case a failure should be raised when trying to build on an
 earlier OS (or a replaced_by that points to the latest version not
 requiring C++11)?!

 Why would the cxx11 PG not add a libcxx depspec if one is required? Seems
 like the obvious convenience solution to make sure all ports requiring
 C++11 spin the same solution...

-- 
Ticket URL: <https://trac.macports.org/ticket/57335#comment:2>
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