pkg/55798: GTK3 build failure on macOS with quartz option enabled (dyld: Symbol not found: _NSApp)

[dan%alt.md@localhost]

>Number:         55798
>Category:       pkg
>Synopsis:       GTK3 build failure on macOS with quartz option enabled (dyld: Symbol not found: _NSApp)
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Nov 09 10:25:00 +0000 2020
>Originator:     Dan Cîrnaț
>Release:        pkgsrc-current
>Organization:
>Environment:
Darwin Dans-MBP-4 19.6.0 Darwin Kernel Version 19.6.0: Mon Aug 31 22:12:52 PDT 2020; root:xnu-6153.141.2~1/RELEASE_X86_64 x86_64
>Description:
GTK3 build fails on macOS when I enable the `quartz` option.

>These options are currently enabled:
>	gtk3-atk-bridge quartz x11

> ...
>Making all in .
>  GEN      gdkconfig.h
>  GISCAN   Gdk-3.0.gir
>dyld: Symbol not found: _NSApp
>  Referenced from: /opt/pkg/src/x11/gtk3/work/gtk+-3.24.23/gdk/.libs/libgdk-3.0.dylib
>  Expected in: flat namespace
> in /opt/pkg/src/x11/gtk3/work/gtk+-3.24.23/gdk/.libs/libgdk-3.0.dylib
>Command '['/opt/pkg/src/x11/gtk3/work/gtk+-3.24.23/gdk/tmp-introspectbr6qax7p/Gdk-3.0', '-->introspect-dump=/opt/pkg/src/x11/gtk3/work/gtk+-3.24.23/gdk/tmp->introspectbr6qax7p/functions.txt,/opt/pkg/src/x11/gtk3/work/gtk+-3.24.23/gdk/tmp->introspectbr6qax7p/dump.xml']' died with <Signals.SIGABRT: 6>.
>gnumake[4]: *** [Gdk-3.0.gir] Error 1
>gnumake[3]: *** [all-recursive] Error 1
>gnumake[2]: *** [all] Error 2
>gnumake[1]: *** [all-recursive] Error 1
>gnumake: *** [all] Error 2
>*** Error code 2
>
>Stop.
>bmake[1]: stopped in /opt/pkg/src/x11/gtk3
>*** Error code 1
>
>Stop.
>bmake: stopped in /opt/pkg/src/x11/gtk3
>How-To-Repeat:
cd x11/gtk3
bmake PKG_OPTIONS.gtk3=quartz
>Fix: