[MacPorts] #58199: cmake: build failure on OSX 10.11 due to LegacySupport PortGroup

[MacPorts]

#58199: cmake: build failure on OSX 10.11 due to LegacySupport PortGroup
---------------------+-----------------------
  Reporter:  dbl001  |      Owner:  michaelld
      Type:  defect  |     Status:  assigned
  Priority:  Normal  |  Milestone:
 Component:  ports   |    Version:  2.5.4
Resolution:          |   Keywords:
      Port:  cmake   |
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Comment (by michaelld):

 In [changeset:"5eba5a27c81f2b508944bcee3216f753ec6c4c45/macports-ports"
 5eba5a27c81f2b508944bcee3216f753ec6c4c45/macports-ports] (master):
 {{{
 #!ConfigurableCommitTicketReference repository="macports-ports"
 revision="5eba5a27c81f2b508944bcee3216f753ec6c4c45"
 cmake: temporary fix for LegacySupport issue

 Hopefully addresses < https://trac.macports.org/ticket/58199 > and <
 https://trac.macports.org/ticket/58200 >.

 Just temporary while we figure out a better way to handle this specific
 circumstance within the LegacySupport headers.

 We believe that Xcode 8+ provides "clock_gettime"; we know this is true
 for Xcode 8.2.1, and we know that Xcode 7.2.1. does not provide this
 feature. legacysupport is used for 10.11 just for this specific feature,
 so use it only if OSX <= 10.11 && Xcode < 8.

 See also < https://trac.macports.org/wiki/XcodeVersionInfo > for the
 various combinations of OSX and Xcode versions.
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/58199#comment:31>
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