Godot crash when printing info about leaked nodes due to optional forced flush

[qarmin]

Godot version:
3.2.4.beta.custom_build. adfc646 - but code is similar in version 4

Regression from #44393 - CC @Calinou

OS/device including version:
Ubuntu 20.04

Issue description:
When info about leaked nodes is printed, then Godot crash

ERROR: ~List: Condition "_first != __null" is true.
   At: ./core/self_list.h:112.
ERROR: ~List: Condition "_first != __null" is true.
   At: ./core/self_list.h:112.
WARNING: cleanup: ObjectDB instances leaked at exit (run with --verbose for details).
   At: core/object.cpp:2132.
Leaked instance: GDScriptNativeClass:563
core/io/logger.cpp:234:7: runtime error: member access within null pointer of type 'struct ProjectSettings'
core/object.cpp:484:6: runtime error: member access within null pointer of type 'const struct Object'
handle_crash: Program crashed with signal 11
Dumping the backtrace. 
[1] godots() [0x13aec6a] (/mnt/Miecz/godot3.2/platform/x11/crash_handler_x11.cpp:54)
[2] /lib/x86_64-linux-gnu/libc.so.6(+0x46210) [0x7fc0f58c6210] (??:0)
[3] Object::get(StringName const&, bool*) const (/mnt/Miecz/godot3.2/core/object.cpp:484)
[4] StdLogger::logv(char const*, __va_list_tag*, bool) (/mnt/Miecz/godot3.2/core/io/logger.cpp:234 (discriminator 2))
[5] CompositeLogger::logv(char const*, __va_list_tag*, bool) (/mnt/Miecz/godot3.2/core/io/logger.cpp:256 (discriminator 1))
[6] OS::print(char const*, ...) (/mnt/Miecz/godot3.2/core/os/os.cpp:132)
[7] print_line(String) (/mnt/Miecz/godot3.2/core/print_string.cpp:80 (discriminator 4))
[8] ObjectDB::cleanup() (/mnt/Miecz/godot3.2/core/object.cpp:2149 (discriminator 17))
[9] unregister_core_types() (/mnt/Miecz/godot3.2/core/register_core_types.cpp:313)
[10] Main::cleanup() (/mnt/Miecz/godot3.2/main/main.cpp:2299)
[11] godots(main+0x336) [0x13a5b5c] (/mnt/Miecz/godot3.2/platform/x11/godot_x11.cpp:59)
[12] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf3) [0x7fc0f58a70b3] (??:0)
[13] godots(_start+0x2e) [0x13a576e] (??:?)
-- END OF BACKTRACE --
Przerwane (zrzut pamięci)

Relevant code - https://github.com/godotengine/godot/blame/adfc646f8cb497d520ea2238482ab674fe90d43a/core/io/logger.cpp#L234-L238

Steps to reproduce:

1. Run minimal project with this flags - godot -e -q -v

Minimal reproduction project:
https://github.com/jegor377/godot-gdgifexporter/archive/8e754c09dc10ec1f25ec2510c688bc1b35ee6b64.zip

[akien-mga]

@Calinou GLOBAL_GET is likely not safe to use in such core code which outlives ProjectSettings.
You should likely get the result in the constructor and cache it, not query in logv.

[akien-mga]

You should likely get the result in the constructor and cache it, not query in logv.

For the reference, GLOBAL_GET in the constructor segfaults, that's likely too early. We can't make assumptions on the available of ProjectSettings in the logging code which starts before most things and ends before most things.

It might also be possible to trigger a crash by printing stuff before the ProjectSettings are created.

If this should be made configurable, the option probably needs to be enabled in the ProjectSettings code.

I'll revert the 3.2 cherry-pick for now while we work on a solution for master.

[groud]

Would be great to fix it I need it for debugging. I'll try to fix it.