Infinite loop freeze/crash in AnimationNodeStateMachine

[Flynsarmy]

Godot version

4.1.rc3.official

System information

Windows 11, Nvidia Geforce RTX 3070 TI

Issue description

AnimationNodeStateMachine is capable of infinite looping resulting in a freeze and eventual crash. While this is happening, the console is being spammed with:

ERROR: Failed method: EditorToaster::_error_handler_impl. Message queue out of memory. Message queue out of memory. Try increasing 'memory/limits/message_queue/max_size_mb' in project settings.
at: push_callablep (core/object/message_queue.cpp:96)

This happens when you point animations at each other with no conditions (ie the default state for connections).

Steps to reproduce

• Add a character to your scene with an AnimationPlayer (with some anims) and AnimationTree
• Set an AnimationNodeStateMachine as the AnimationTree root.
• Add two animations, point them at each other, then point Start at the first animation.

Godot will infinite loop and freeze then eventually crash.

Minimal reproduction project

• Git clone https://github.com/Flynsarmy/gd-statemachine-crash
• In the AnimationTree window click 'Connect Nodes' and drag from 'Start' to 'female-locomotion_idle'.

2023-07-05.21-33-26.mp4

[AThousandShips]

• Related: Crash when setting AnimationTree active with circular dependency (infinite loop) #79012

[Flynsarmy]

Ah, appears to be a duplicate. Closing