docs/reference/gdk/gdk4-overrides.txt

<MACRO>
<NAME>GDK_WINDOWING_X11</NAME>
#define GDK_WINDOWING_X11
</MACRO>

<MACRO>
<NAME>GDK_WINDOWING_WIN32</NAME>
#define GDK_WINDOWING_WIN32
</MACRO>

<MACRO>
<NAME>GDK_WINDOWING_QUARTZ</NAME>
#define GDK_WINDOWING_QUARTZ
</MACRO>

<MACRO>
<NAME>GDK_WINDOWING_WAYLAND</NAME>
#define GDK_WINDOWING_WAYLAND
</MACRO>

<MACRO>
<NAME>GDK_DISABLE_DEPRECATION_WARNINGS</NAME>
#define GDK_DISABLE_DEPRECATION_WARNINGS
</MACRO>