Could not resolve super class "SomeClassName".

[DiceWithSpades]

Tested versions

• Reproducible in: v4.5.beta1
• Not reproducible in: v4.4.1.stable

System information

Godot v4.5.beta1 - macOS Sequoia (15.5.0) - Multi-window, 3 monitors - Metal (Forward+) - integrated Apple M4 (Apple9) - Apple M4 (10 threads) - 24.00 GiB memory

Issue description

When scene and related to it script is opened it will randomly produce below error during saving if mentioned script extends some custom class (I've tested it with abstract and without - it does not change the result).

ERROR: res://node.gd:1 - Parse Error: Could not resolve super class "BaseStuff".
ERROR: modules/gdscript/gdscript.cpp:3021 - Failed to load script "res://node.gd" with error "Parse error".

Steps to reproduce

1. Create script with abstract class (example: abstract class_name BaseStuff extends Node with name base_stuff.gd).
2. Create scene based on Node and save it to file.
3. Add script to created scene, change extends Node to extends BaseStuff and save it to file.
4. Make sure BaseStuff script and scene script are open in editor and click on the node in the scene tree.
5. Use your OS shortcut to save (in my case it was CMD+S).
6. Repeat 5 until error shows (in my case every second time it appears).

Minimal reproduction project (MRP)

• Reproduction steps will work in a fresh project.
• It also appeared on Windows 11, but required more repeats of 5th step.

[AThousandShips]

Please provide an MRP to make this easier to test and fix:

• A small Godot project which reproduces the issue, with no unnecessary files included. Be sure to not include the .godot folder in the archive (but keep project.godot).
• Having an MRP is very important for contributors to be able to reproduce the bug in the same way that you are experiencing it. When testing a potential fix for the issue, contributors will use the MRP to validate that the fix is working as intended.
• Drag and drop a ZIP archive to upload it (max 10 MB). Do not select another field until the project is done uploading.
• Note for C# users: If your issue is not C#-specific, please upload a minimal reproduction project written in GDScript. This will make it easier for contributors to reproduce the issue locally as not everyone has a .NET setup available.

[DiceWithSpades]

Here is a minimal project:

1. Import project in Godot v4.5.beta1.
2. Open node.tscn, node.gd and base_stuff.gd.
3. Click on Node in active scene tree.
4. Click repeatedly save shortcut (CMD+S macOS, Ctrl+S for Win/Linux) until error appears in Output.

godot-bug-repro.zip

[Notgoyome]

Enregistrement.de.l.ecran.2025-06-24.000959.mp4

is it like that ?

Godot v4.5.beta1. windows 11

[precup]

Oh weird, it took me a bit to reproduce this, and I'm not yet sure why it randomly happened, but I have seen it twice now. Not sure I'll be able to bisect unless I can get it to reproduce more reliably.

Godot v4.5.beta (46c495c) - Windows 10 (build 19045) - Multi-window, 3 monitors - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 2080 Ti (NVIDIA; 31.0.15.3713) - AMD Ryzen 9 3900X 12-Core Processor (24 threads) - 31.94 GiB memory

EDIT: just spent another 8 minutes trying to get it to happen again after reopening the editor and can't get it to reproduce, unfortunately. When it did happen previously, it was easy to cause it to happen again on the same copy of the editor.

[DiceWithSpades]

@Notgoyome editor must be in Script tab for this to happen.
@precup for me it happens more often, but sometimes randomly works without showing this issue.

Maybe operating system affects the results. I tested what was possible on my side: on macOS it happens very often (noticeable during normal work on a project without trying to invoke it) , Windows 11 from time to time (during normal work it would be much less noticeable than macOS), on Linux (Mint) I was not able to make it happen.

Here is recording from macOS:

screen-recording.mp4

[anvilfolk]

Having this happen on my personal project too. Hard to get down to MRP with it sometimes not happening. In my case, it was also occasionally but not always accompanied by

  ERROR: Cyclic inheritance in script class.

Pointing to this part of the code in modules/gdscript/gdscript.cpp

		for (int i = 0; i < base_caches.size(); i++) {
			if (base_caches[i] == base_cache.ptr()) {
				if (r_err) {
					*r_err = true;
				}
				valid = false; // to show error in the editor
				base_cache->valid = false;
				base_cache->inheriters_cache.clear(); // to prevent future stackoverflows
				base_cache.unref();
				base.unref();
				_base = nullptr;
				ERR_FAIL_V_MSG(false, "Cyclic inheritance in script class.");
			}
		}