Crash on hot reload when binding gd pointers

[theKidOfArcrania]

There is an issue in hot reloading where godot would segfault if you bind to self node when it gets hot reloaded.

Minimum example:

use godot::prelude::*;

#[repr(C)]
#[derive(GodotClass)]
#[class(init, base = Node, tool)]
pub struct MyNode {
    test: u64,
    base: Base<Node>,
}

#[godot_api]
impl INode for MyNode {
    fn ready(&mut self) {
        let call = Callable::from_local_fn(
            "test",
            |_| {
                Ok(Variant::nil())
            },
        ).bindv(&Array::from_iter([self.to_gd().to_variant()]));
        self.base_mut().connect(c"tree_entered", &call);
    }
}

struct Test;

#[gdextension]
unsafe impl ExtensionLibrary for Test {}

When a scene with this node is loaded in godot, and then you rebuild (and thus trigger a hot reload), and then attempt to close that scene, it will then cause godot to crash entirely.

[Bromeon]

Thanks for reporting. Is it crash or panic? Where exactly, do you have a stacktrace?

[theKidOfArcrania]

It's a segmentation fault. I don't have a stack trace for this simple version since this one actually just directly segfaults without even dumping any errors

Although I think it is crashing somewhere in godot_core::builtin::callable::custom_callable::rust_callable_to_string_named because that was a stacktrace I found when running my actual code

[theKidOfArcrania]

When I get some time later, I can pull it up into gdb and dump the stacktrace that way