[MacPorts] #71253: gegl-devel @0.4.50: builds fail on 10.13/10.14: dispatch.h: error: expected value in expression (HAVE_UNISTD_H)

[MacPorts]

#71253: gegl-devel @0.4.50: builds fail on 10.13/10.14: dispatch.h: error: expected
value in expression (HAVE_UNISTD_H)
---------------------+------------------------
 Reporter:  mascguy  |      Owner:  mascguy
     Type:  defect   |     Status:  assigned
 Priority:  Normal   |  Milestone:
Component:  ports    |    Version:  2.10.4
 Keywords:           |       Port:  gegl-devel
---------------------+------------------------
 Xcode Clang 9.x and 10.x fails on the following, for 10.13/10.14:

 {{{
 gegl-init.c.o -c ../gegl-0.4.50/gegl/gegl-init.c
 In file included from ../gegl-0.4.50/gegl/gegl-init.c:59:
 In file included from
 /System/Library/Frameworks/Foundation.framework/Headers/Foundation.h:6:
 In file included from
 /opt/local/include/LegacySupport/CoreFoundation/CoreFoundation.h:27:
 In file included from
 /System/Library/Frameworks/CoreFoundation.framework/Headers/CoreFoundation.h:60:
 In file included from
 /System/Library/Frameworks/CoreFoundation.framework/Headers/CFPropertyList.h:17:
 In file included from
 /System/Library/Frameworks/CoreFoundation.framework/Headers/CFStream.h:20:
 /usr/include/dispatch/dispatch.h:38:45: error: expected value in
 expression
 #if !defined(HAVE_UNISTD_H) || HAVE_UNISTD_H
                                             ^
 }}}

 Via the following new import in `gegl-init.c`, added with release 0.4.50:

 {{{
 #ifdef __APPLE__
 #import <Foundation/Foundation.h>
 #endif
 }}}

 Thoughts as to how we should deal with this, apart from blacklisting Clang
 9.x/10.x (which seems absurd)?

-- 
Ticket URL: <https://trac.macports.org/ticket/71253>
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