Accessing a nonexistent variable in a separate thread does not throw an error

[Miziziziz]

Godot version

v3.3.3.stable.mono.official [b973f99]

System information

Windows 10

Issue description

if you have a separate thread running and try to access a variable that does not exist, it will not throw an error or anything, the thread simply stops working without any indication of how or why.

Steps to reproduce

run a script with this code:

extends Node

var thread = Thread.new()

func _ready():
	thread.start(self, "calc", self)

func calc(data):
	print('here')
	var l = data.position
	print('now here')

the output console will only say 'here', there will be no errors thrown in debugger

Minimal reproduction project

MultiThreadError.zip

[Rubonnek]

I think you meant the Output tab in the Editor's bottom panel, not the console output. Is that right?

I'm able to see the following message in the console/terminal in both Linux and Windows:

Godot Engine v3.4.beta.custom_build.16642e283 - https://godotengine.org
OpenGL ES 3.0 Renderer: AMD Radeon RX 6900 XT (SIENNA_CICHLID, DRM 3.41.0, 5.13.12-arch1-1, LLVM 12.0.1)
OpenGL ES Batching: ON
 
Running: /opt/godot/bin/godot.x11.opt.tools.64 --path /home/wilson/Downloads/huehuehue/MultiThreadError --remote-debug 127.0.0.1:6007 --allow_focus_steal_pid 1661 --position 448,240
Godot Engine v3.4.beta.custom_build.16642e283 - https://godotengine.org
OpenGL ES 3.0 Renderer: AMD Radeon RX 6900 XT (SIENNA_CICHLID, DRM 3.41.0, 5.13.12-arch1-1, LLVM 12.0.1)
OpenGL ES Batching: ON
 
here
SCRIPT ERROR: Invalid get index 'position' (on base: 'Spatial (Node.gd)').
          at: calc (res://Node.gd:11)

[Zylann]

Related: #18330

[Miziziziz]

Woops yeah I meant output tab