[MacPorts] #60926: gtk2 +quartz -x11: error: implicit declaration of function 'gdk_quartz_pasteboard_type_to_atom_libgtk_only' is invalid in C99

[MacPorts]

#60926: gtk2 +quartz -x11: error: implicit declaration of function
'gdk_quartz_pasteboard_type_to_atom_libgtk_only' is invalid in C99
---------------------------+--------------------
  Reporter:  chicagotripp  |      Owner:  (none)
      Type:  defect        |     Status:  new
  Priority:  Normal        |  Milestone:
 Component:  ports         |    Version:  2.6.3
Resolution:                |   Keywords:
      Port:  gtk2          |
---------------------------+--------------------

Comment (by chicagotripp):

 I found that it builds fine on my other Mac running Catalina 10.15.6
 (Beta) Build 19G73, XCode 11.0, Macports 2.6.3. The XCode is the only
 difference besides hardware. My other hardware is a MacBook Pro 16 (2019)
 and the one with the stable XCode is a MacBook Pro 15 (Mid-2015). It has
 these ports installed with the following variants, yet working:
 {{{
 port installed|grep x11
 }}}
 {{{
   cairo @1.16.0_0+quartz+x11 (active)
   gd2 @2.3.0_0+x11 (active)
   ghostscript @9.52_0+x11 (active)
   giflib @4.2.3_0+x11 (active)
   graphviz @2.40.1_2+pangocairo+x11 (active)
   py27-cairo @1.18.2_0+quartz+x11 (active)
   py38-cairo @1.19.1_0+quartz+x11 (active)
 }}}
 {{{
 port installed|grep gimp
 }}}
 {{{
   gimp-help-en @2.10.0_0 (active)
   gimp2 @2.10.18_4+python27+quartz (active)
 }}}
 Maybe something in XCode 12 Beta 3 is breaking the build? I hope this
 helps. My install with the stable XCode 11 is not a fresh install. I will
 wipe everything and rebuild to see if I am able to replicate the same
 behavior as my system running XCode 12 Beta 3.

-- 
Ticket URL: <https://trac.macports.org/ticket/60926#comment:4>
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