[MacPorts] #56511: gcc49 @4.9.4_2: build fails with Xcode 9 on macOS 10.12

[MacPorts]

#56511: gcc49 @4.9.4_2: build fails with Xcode 9 on macOS 10.12
-----------------------+--------------------
  Reporter:  mopihopi  |      Owner:  (none)
      Type:  defect    |     Status:  new
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:
Resolution:            |   Keywords:
      Port:  gcc49     |
-----------------------+--------------------

Comment (by kencu):

 can we agree that the fail test in gcc43-gcc49 should be:
 {{{
 if {${os.platform} eq "darwin" && ([vercmp $xcodeversion 9.0] > 0)} {
     depends_lib
     depends_run
     archive_sites
     pre-fetch {
         ui_error "building ${name} is not supported with Xcode 9 or
 greater"
         return -code error {unsupported platform}
     }
 }
 }}}

 If so, I have a commit ready to do that.

-- 
Ticket URL: <https://trac.macports.org/ticket/56511#comment:12>
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