[MacPorts] #44129: cmake: fix build against libc++ on Lion

[MacPorts]

#44129: cmake: fix build against libc++ on Lion
----------------------+-------------------
  Reporter:  mojca@…  |      Owner:  css@…
      Type:  defect   |     Status:  new
  Priority:  Normal   |  Milestone:
 Component:  ports    |    Version:
Resolution:           |   Keywords:  lion
      Port:  cmake    |
----------------------+-------------------

Comment (by larryv@…):

 [[browser:tags/release_2_3_1/base/src/port1.0/portconfigure.tcl#L426]]

-- 
Ticket URL: <https://trac.macports.org/ticket/44129#comment:7>
MacPorts <http://www.macports.org/>
Ports system for OS X