[MacPorts] #54135: clang-4.0 error building software on 10.6 (or less) due to #include_next <float.h>

[MacPorts]

#54135: clang-4.0 error building software on 10.6 (or less) due to #include_next
<float.h>
------------------------+---------------------------------------
  Reporter:  kencu      |      Owner:  jeremyhu
      Type:  defect     |     Status:  assigned
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:
Resolution:             |   Keywords:  snowleopard leopard tiger
      Port:  clang-4.0  |
------------------------+---------------------------------------

Comment (by jeremyhu):

 {{{
 diff --git a/lib/Headers/float.h b/lib/Headers/float.h
 index 0f453d87cb..1db2b28ed7 100644
 --- a/lib/Headers/float.h
 +++ b/lib/Headers/float.h
 @@ -31,7 +31,12 @@
   * Also fall back on Darwin to allow additional definitions and
   * implementation-defined values.
   */
 -#if (defined(__APPLE__) || (defined(__MINGW32__) || defined(_MSC_VER)))
 && \
 +
 +#if defined(__APPLE__) && __has_include(<Availability.h>)
 +#include <Availability.h>
 +#endif
 +
 +#if ((defined(__APPLE__) && __has_include(<Availability.h>) &&
 (!defined(__MAC_OS_X_VERSION_MAX_ALLOWED) ||
 __MAC_OS_X_VERSION_MAX_ALLOWED >= 101300)) || (defined(__MINGW32__) ||
 defined(_MSC_VER))) && \
      __STDC_HOSTED__ && __has_include_next(<float.h>)
  #  include_next <float.h>
 }}}

--
Ticket URL: <https://trac.macports.org/ticket/54135#comment:16>
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