[MacPorts] #59224: gcc8 @8.3.0_4: confused by __OSX_AVAILABLE_STARTING

[MacPorts]

#59224: gcc8 @8.3.0_4: confused by __OSX_AVAILABLE_STARTING
--------------------------+----------------------
  Reporter:  MaddTheSane  |      Owner:  (none)
      Type:  defect       |     Status:  new
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:  2.6.1
Resolution:               |   Keywords:  catalina
      Port:  gcc8         |
--------------------------+----------------------

Comment (by sjc999):

 I've a bit of a hack to fix it. The issue is that some macros are
 undefined - they are in
 /Library/Developer/CommandLineTools/SDKs/MacOSX10.15.sdk/usr/include/Availability.h

 I'm not sure if this is a gcc or Xcode bug (the latter, I think). The
 #if's in Availability.h I think are wrong (not had time to really check -
 they are a little Dover the opt with their nesting) but it can leave the
 macros undefined. In that file, near the top just after #include
 <AvailabilityInternal.h> add the three lines:

 #define __OSX_AVAILABLE_STARTING(_osx, _ios)

 #define __OSX_AVAILABLE_BUT_DEPRECATED(_osxIntro, _osxDep, _iosIntro,
 _iosDep)

 #define __OSX_AVAILABLE_BUT_DEPRECATED_MSG(_osxIntro, _osxDep, _iosIntro,
 _iosDep, _msg)


 which will at least give the macros default (null) behaviour and allows
 gcc8 to install.

-- 
Ticket URL: <https://trac.macports.org/ticket/59224#comment:3>
MacPorts <https://www.macports.org/>
Ports system for macOS