Editor crashes when changing type of node after editing child scene

[emanresU102396]

Tested versions

v4.2.2.stable.official [15073af]

System information

Godot v4.2.2.stable - Windows 10.0.22631 - GLES3 (Compatibility) - NVIDIA GeForce RTX 4080 Laptop GPU (NVIDIA; 31.0.15.4633) - AMD Ryzen 9 7940HS w/ Radeon 780M Graphics (16 Threads)

Issue description

When one scene is instantiated in another, and I edit the child scene, then changing the type of the parent scene causes the engine to crash. (Expected behavior: Not doing that.)

Steps to reproduce

With the MRP:

1. Rename the root node in child_scene, or change its type.
2. Right click the root node in main_scene, click 'Change Type', and try to change it.

Minimal reproduction project (MRP)

change node crash test.zip

[iltenahmet]

I was able to reproduce this issue in the 4.2.2 official build but not in the custom build from the latest version of the master branch:
Reproduced in -> v4.2.2.stable.mono.official [15073af]
Couldn't reproduce in -> v4.3.dev.custom_build [4a01602]

My system: Windows 11 22631.3447 - NVIDIA GeForce GTX 1650 Ti GPU - Intel Core i7-10750H CPU

[AThousandShips]

Sounds like:

• Godot crashes, when you change root node to something unpredictable #89425

Which solved the issue in 4.3, but due to regressions introduced by it that fix was not cherry picked for 4.2, unsure what kind of specific solution to backport here, the new fix for this in 4.3 has not been marked for cherry picking as of right now, see:

• Fix node duplication in update after external changes. #89992

That one broke compatibility though, and I think it too was replaced down the line

CC @ajreckof

[ajreckof]

Yeah this one was tricky and down the line we realised we needed to break compatibility to properly fix it. It shouldn't be hard to cherry-pick as compatibility breakage we're made separately but on the other hand I'm wondering if they are worth it because the crash is really hard to reproduce without steps. On the other hand this report shows that it does in fact happen often enough for someone to report it. If needed I can point to what commits should be cherry picked to fix this on 4.2

Edit : the mix I'm suggesting wouldn't break compatibility

[eternity336]

I don't know if this is the same issue, but this is an error I get every time I try to save a scene. The editor freezes up, and I have to force close it.

`Godot Engine v4.2.stable.official.46dc27791 - https://godotengine.org
Vulkan API 1.3.277 - Forward+ - Using Vulkan Device #0: NVIDIA - NVIDIA GeForce RTX 3070 Ti Laptop GPU

WARNING: Blend file import is enabled in the project settings, but no Blender path is configured in the editor settings.
at: _editor_init (modules/gltf/register_types.cpp:63)
ERROR: Resource was not pre cached for the resource section, bug?
at: (scene/resources/resource_format_text.cpp:1853)
ERROR: Resource was not pre cached for the resource section, bug?
at: (scene/resources/resource_format_text.cpp:1853)
ERROR: Resource was not pre cached for the resource section, bug?
at: (scene/resources/resource_format_text.cpp:1853)
ERROR: Resource was not pre cached for the resource section, bug?
at: (scene/resources/resource_format_text.cpp:1853)
ERROR: Resource was not pre cached for the resource section, bug?
at: (scene/resources/resource_format_text.cpp:1853)
ERROR: Resource was not pre cached for the resource section, bug?
at: (scene/resources/resource_format_text.cpp:1853)
ERROR: Resource was not pre cached for the resource section, bug?
at: (scene/resources/resource_format_text.cpp:1853)
ERROR: Resource was not pre cached for the resource section, bug?
at: (scene/resources/resource_format_text.cpp:1853)
ERROR: Resource was not pre cached for the resource section, bug?
at: (scene/resources/resource_format_text.cpp:1853)
ERROR: Resource was not pre cached for the resource section, bug?
at: (scene/resources/resource_format_text.cpp:1853)
ERROR: Resource was not pre cached for the resource section, bug?
at: (scene/resources/resource_format_text.cpp:1853)
ERROR: Resource was not pre cached for the resource section, bug?
at: (scene/resources/resource_format_text.cpp:1853)
ERROR: Resource was not pre cached for the resource section, bug?
at: (scene/resources/resource_format_text.cpp:1853)
ERROR: Resource was not pre cached for the resource section, bug?
at: (scene/resources/resource_format_text.cpp:1853)
ERROR: Resource was not pre cached for the resource section, bug?`

[ajreckof]

No this isn't related to this issue. This issue happens when changing the type of the root node which doesn't seem to be your case.

[akien-mga]

Yeah this one was tricky and down the line we realised we needed to break compatibility to properly fix it. It shouldn't be hard to cherry-pick as compatibility breakage we're made separately but on the other hand I'm wondering if they are worth it because the crash is really hard to reproduce without steps. On the other hand this report shows that it does in fact happen often enough for someone to report it. If needed I can point to what commits should be cherry picked to fix this on 4.2

Edit : the mix I'm suggesting wouldn't break compatibility

If you're up for it, I'd say the best would be that you can make a dedicated 4.2 PR with the relevant commits cherry-picked (or manually backported if needed). When cherry-picking, remember to use git cherry-pick -x so that the reference of the original commit hash gets added to the commit description for traceability.

[akien-mga]

Closing as fixed in 4.3.