[MacPorts] #69867: legacy-support headers should work with later SDK versions

[MacPorts]

#69867: legacy-support headers should work with later SDK versions
-----------------------------+-----------------------
  Reporter:  fhgwright       |      Owner:  fhgwright
      Type:  defect          |     Status:  assigned
  Priority:  Low             |  Milestone:
 Component:  ports           |    Version:  2.9.3
Resolution:                  |   Keywords:
      Port:  legacy-support  |
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Comment (by fhgwright):

 In [changeset:"042b096f96bf4ade801b8bf1c734f812c202173c/macports-legacy-
 support" 042b096f96bf4ade801b8bf1c734f812c202173c/macports-legacy-support]
 (master):
 {{{
 #!ConfigurableCommitTicketReference repository="macports-legacy-support"
 revision="042b096f96bf4ade801b8bf1c734f812c202173c"
 Convert some feature flags to the new scheme.

 This reworks the flags that interact with __DARWIN_C_LEVEL
 conditionals, to allow proper testing with different SDKs.

 Re: https://trac.macports.org/ticket/69867

 Also fixes a warning and cleans up some whitespace in sys/stat.h.

 TESTED:
 Builds and passes tests on all platforms, including with allowable
 mismatched SDK cases.
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/69867#comment:16>
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