Do not use std::quick_exit on macOS with libstdc++ or otherwise fix it: error: 'quick_exit' is not a member of 'std'

[barracuda156]

Game and System Information

wesnoth 1.16.9
macOS 10.6
GCC 12.3.0

Description of the bug

:info:build /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_games_wesnoth/wesnoth/work/wesnoth-1.16.9/src/gui/dialogs/loading_screen.cpp:185:22: error: 'quick_exit' is not a member of 'std'
:info:build   185 |                 std::quick_exit(0);
:info:build       |                      ^~~~~~~~~~

There is also another error, which seems not to stop the build from proceeding though:

:info:build /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_games_wesnoth/wesnoth/work/wesnoth-1.16.9/src/serialization/schema/type.cpp:38:36: error: 'monostate' in namespace 'std' does not name a type
:info:build    38 |         bool operator()(const std::monostate&) const
:info:build       |                                    ^~~~~~~~~

Steps to reproduce the behavior

Build with GCC on macOS

Expected behavior

It should build fine :)

Additional context

See the comment of @ryandesign on some details: https://trac.macports.org/ticket/67811#comment:1

[soliton-]

Should be fixed with 6ce218f. Thanks for the report!

[CelticMinstrel]

I also fixed your second error.

[barracuda156]

@CelticMinstrel Thank you!