It's mostly not used anymore and doesn't do what it says it does.
The docs state that it affects GList, GSList, GNode, GMemChunks, GSignal,
GType n_preallocs and GBSearchArray while:
* GList, GSList and GNode use GSlice and are not affected
* GMemChunks is gone
* GType npreallocs is ignored
It also states that it can be used to force the usage of g_malloc/g_free,
which is handled by G_SLICE=always-malloc now.
The only places where it's used is in signal handling through GBSearchArray
and in GValueArray (deprecated). Since it's unlikely that anyone wants to
reduce allocation sizes just for those cases remove the build option.
ENABLE_GC_FRIENDLY_DEFAULT was supposed to set the default for the gc friendliness
while still allowing to force enable it at runtime with G_DEBUG=gc-friendly.
With commit 943a18b564 (6 years ago) things were changed to always set it
according to the content of G_DEBUG in glib_init(), making the default unused.
Since nobody complained since then just remove the macro and the build option.
Hopefully discouraging people from overriding that and building with it
enabled.
Pro-tip: GLib will break.
Signed-off-by: Philip Withnall <withnall@endlessm.com>
https://bugzilla.gnome.org/show_bug.cgi?id=791622
