4.3 dev6 C# Clearing a dictionary, then creating a new one on an exported property in the inspector crashes the editor

[TravisZovko]

Tested versions

• Reproducible in v4.3.dev6.mono.official [89850d5]
• Not reproducible in v4.2.2.stable.mono.official [15073af]

System information

Godot v4.3.dev6.mono - Windows 10.0.19045 - Vulkan (Forward+) - dedicated Radeon RX 590 Series (Advanced Micro Devices, Inc.; 31.0.21912.14) - AMD Ryzen 5 3600 6-Core Processor (12 Threads)

Issue description

I have a scene with a Node with an attached C# script that exports a Godot.Collections.Dictionary.
In the inspector for that Node, if I create a new Dictionary in the exported property, then delete it, then create a new dictionary, the editor crashes. This crash does not occur in 4.2.

Steps to reproduce

• Create a Node and attach a C# script which exports a Dictionary, like so:

public partial class NodeWithExportedDictionary : Node
{
	[Export]
	public Godot.Collections.Dictionary<Vector2I, string> MyDict { get; set; }

	[Export]
	public Godot.Collections.Dictionary MyOtherDict { get; set; }
}

• In the inspector, click on the spot marked 'Dictionary (nil) to add a new dictionary.
• Erase the Dictionary by clicking the 'revert to default' arrow next to the property.
• Click to add a new dictionary again. The editor crashes after a second when I do this on my machine.

Minimal reproduction project (MRP)

DictionaryExportBug.zip

[raulsntos]

I can reproduce in v4.3.dev.mono.custom_build [ffc41fb]. Here's a stacktrace:

* thread #1, name = 'godot.linuxbsd.', stop reason = signal SIGSEGV: address not mapped to object (fault address: 0x2f0)
  * frame #0: 0x000055555dc511d8 godot.linuxbsd.editor.dev.x86_64.llvm.mono`Node::add_child(this=0x0000000000000000, p_child=0x000055557d576510, p_force_readable_name=false, p_internal=INTERNAL_MODE_DISABLED) at node.cpp:1557:2
    frame #1: 0x000055555c9c4af4 godot.linuxbsd.editor.dev.x86_64.llvm.mono`EditorPropertyDictionary::_create_new_property_slot(this=0x000055557cc4e2b0, p_idx=0) at editor_properties_array_dict.cpp:907:28
    frame #2: 0x000055555c9c5980 godot.linuxbsd.editor.dev.x86_64.llvm.mono`EditorPropertyDictionary::update_property(this=0x000055557cc4e2b0) at editor_properties_array_dict.cpp:999:5
    frame #3: 0x000055555c9c75dd godot.linuxbsd.editor.dev.x86_64.llvm.mono`EditorPropertyDictionary::_edit_pressed(this=0x000055557cc4e2b0) at editor_properties_array_dict.cpp:1114:2
    frame #4: 0x000055555cb64099 godot.linuxbsd.editor.dev.x86_64.llvm.mono`void call_with_variant_args_helper<EditorPropertyDictionary>(p_instance=0x000055557cc4e2b0, p_method=(godot.linuxbsd.editor.dev.x86_64.llvm.mono`EditorPropertyDictionary::_edit_pressed() at editor_properties_array_dict.cpp:1106), p_args=0x0000000000000000, r_error=0x00007fffffff7608, (null)=IndexSequence<> @ 0x00007fffffff7118) at binder_common.h:304:2
    frame #5: 0x000055555cb64009 godot.linuxbsd.editor.dev.x86_64.llvm.mono`void call_with_variant_args<EditorPropertyDictionary>(p_instance=0x000055557cc4e2b0, p_method=(godot.linuxbsd.editor.dev.x86_64.llvm.mono`EditorPropertyDictionary::_edit_pressed() at editor_properties_array_dict.cpp:1106), p_args=0x0000000000000000, p_argcount=0, r_error=0x00007fffffff7608) at binder_common.h:418:2
    frame #6: 0x000055555cb63ed5 godot.linuxbsd.editor.dev.x86_64.llvm.mono`CallableCustomMethodPointer<EditorPropertyDictionary>::call(this=0x0000555565628ce0, p_arguments=0x0000000000000000, p_argcount=0, r_return_value=0x00007fffffff75f0, r_call_error=0x00007fffffff7608) const at callable_method_pointer.h:103:3
    frame #7: 0x0000555560ab4386 godot.linuxbsd.editor.dev.x86_64.llvm.mono`Callable::callp(this=0x00007fffffff74d0, p_arguments=0x0000000000000000, p_argcount=0, r_return_value=0x00007fffffff75f0, r_call_error=0x00007fffffff7608) const at callable.cpp:57:11
    frame #8: 0x0000555560ef0140 godot.linuxbsd.editor.dev.x86_64.llvm.mono`Object::emit_signalp(this=0x000055557cc4efd0, p_name=0x0000555562cebe30, p_args=0x0000000000000000, p_argcount=0) at object.cpp:1219:13
    frame #9: 0x000055555dc825f1 godot.linuxbsd.editor.dev.x86_64.llvm.mono`Node::emit_signalp(this=0x000055557cc4efd0, p_name=0x0000555562cebe30, p_args=0x0000000000000000, p_argcount=0) at node.cpp:3884:17
    frame #10: 0x000055555b7ba903 godot.linuxbsd.editor.dev.x86_64.llvm.mono`Error Object::emit_signal<>(this=0x000055557cc4efd0, p_name=0x0000555562cebe30) at object.h:936:10
    frame #11: 0x000055555de5c676 godot.linuxbsd.editor.dev.x86_64.llvm.mono`BaseButton::_pressed(this=0x000055557cc4efd0) at base_button.cpp:137:2
    frame #12: 0x000055555de5c310 godot.linuxbsd.editor.dev.x86_64.llvm.mono`BaseButton::on_action_event(this=0x000055557cc4efd0, p_event=Ref<InputEvent> @ 0x00007fffffff7a08) at base_button.cpp:167:5
    frame #13: 0x000055555de5bfba godot.linuxbsd.editor.dev.x86_64.llvm.mono`BaseButton::gui_input(this=0x000055557cc4efd0, p_event=0x00007fffffff7bc8) at base_button.cpp:68:3
    frame #14: 0x000055555deebb82 godot.linuxbsd.editor.dev.x86_64.llvm.mono`Control::_call_gui_input(this=0x000055557cc4efd0, p_event=0x00007fffffff7bc8) at control.cpp:1825:2
    frame #15: 0x000055555dcaf3d6 godot.linuxbsd.editor.dev.x86_64.llvm.mono`Viewport::_gui_call_input(this=0x000055556433c770, p_control=0x000055557cc4efd0, p_input=0x00007fffffff8e08) at viewport.cpp:1557:14
    frame #16: 0x000055555dcb10e0 godot.linuxbsd.editor.dev.x86_64.llvm.mono`Viewport::_gui_input_event(this=0x000055556433c770, p_event=Ref<InputEvent> @ 0x00007fffffff91b8) at viewport.cpp:1826:64
    frame #17: 0x000055555dcbc1d0 godot.linuxbsd.editor.dev.x86_64.llvm.mono`Viewport::push_input(this=0x000055556433c770, p_event=0x00007fffffffb418, p_local_coords=false) at viewport.cpp:3248:3
    frame #18: 0x000055555dcbadcc godot.linuxbsd.editor.dev.x86_64.llvm.mono`Window::_window_input(this=0x000055556433c770, p_ev=0x00007fffffffb418) at window.cpp:1628:3
    frame #19: 0x000055555de38d6f godot.linuxbsd.editor.dev.x86_64.llvm.mono`void call_with_variant_args_helper<Window, Ref<InputEvent> const&, 0ul>(p_instance=0x000055556433c770, p_method=(godot.linuxbsd.editor.dev.x86_64.llvm.mono`Window::_window_input(Ref<InputEvent> const&) at window.cpp:1580), p_args=0x00007fffffffb8a0, r_error=0x00007fffffffb888, (null)=IndexSequence<0UL> @ 0x00007fffffffb448) at binder_common.h:304:2
    frame #20: 0x000055555de38cb9 godot.linuxbsd.editor.dev.x86_64.llvm.mono`void call_with_variant_args<Window, Ref<InputEvent> const&>(p_instance=0x000055556433c770, p_method=(godot.linuxbsd.editor.dev.x86_64.llvm.mono`Window::_window_input(Ref<InputEvent> const&) at window.cpp:1580), p_args=0x00007fffffffb8a0, p_argcount=1, r_error=0x00007fffffffb888) at binder_common.h:418:2
    frame #21: 0x000055555de38b7d godot.linuxbsd.editor.dev.x86_64.llvm.mono`CallableCustomMethodPointer<Window, Ref<InputEvent> const&>::call(this=0x0000555573defd50, p_arguments=0x00007fffffffb8a0, p_argcount=1, r_return_value=0x00007fffffffba18, r_call_error=0x00007fffffffb888) const at callable_method_pointer.h:103:3
    frame #22: 0x0000555560ab4386 godot.linuxbsd.editor.dev.x86_64.llvm.mono`Callable::callp(this=0x00007fffffffba38, p_arguments=0x00007fffffffb8a0, p_argcount=1, r_return_value=0x00007fffffffba18, r_call_error=0x00007fffffffb888) const at callable.cpp:57:11
    frame #23: 0x000055555ac59c54 godot.linuxbsd.editor.dev.x86_64.llvm.mono`Variant Callable::call<Ref<InputEvent>>(this=0x00007fffffffba38, p_args=Ref<InputEvent> @ 0x00007fffffffba10) const at variant.h:875:2
    frame #24: 0x000055555ac48f4d godot.linuxbsd.editor.dev.x86_64.llvm.mono`DisplayServerX11::_dispatch_input_event(this=0x0000555562126b10, p_event=0x00007fffffffc548) at display_server_x11.cpp:4025:14
    frame #25: 0x000055555ac48bed godot.linuxbsd.editor.dev.x86_64.llvm.mono`DisplayServerX11::_dispatch_input_events(p_event=0x00007fffffffc548) at display_server_x11.cpp:4001:52
    frame #26: 0x0000555560a22f42 godot.linuxbsd.editor.dev.x86_64.llvm.mono`Input::_parse_input_event_impl(this=0x0000555561c1f6a0, p_event=0x00007fffffffc548, p_is_emulated=false) at input.cpp:773:3
    frame #27: 0x0000555560a1ec34 godot.linuxbsd.editor.dev.x86_64.llvm.mono`Input::flush_buffered_events(this=0x0000555561c1f6a0) at input.cpp:1044:3
    frame #28: 0x000055555ac4e7d5 godot.linuxbsd.editor.dev.x86_64.llvm.mono`DisplayServerX11::process_events(this=0x0000555562126b10) at display_server_x11.cpp:5123:26
    frame #29: 0x000055555ac1995c godot.linuxbsd.editor.dev.x86_64.llvm.mono`OS_LinuxBSD::run(this=0x00007fffffffd508) at os_linuxbsd.cpp:958:35
    frame #30: 0x000055555ac0d995 godot.linuxbsd.editor.dev.x86_64.llvm.mono`main(argc=4, argv=0x00007fffffffdb28) at godot_linuxbsd.cpp:85:6
    frame #31: 0x00007ffff7c29d90 libc.so.6`__libc_start_call_main(main=(godot.linuxbsd.editor.dev.x86_64.llvm.mono`main at godot_linuxbsd.cpp:56), argc=4, argv=0x00007fffffffdb28) at libc_start_call_main.h:58:16
    frame #32: 0x00007ffff7c29e40 libc.so.6`__libc_start_main_impl(main=(godot.linuxbsd.editor.dev.x86_64.llvm.mono`main at godot_linuxbsd.cpp:56), argc=4, argv=0x00007fffffffdb28, init=<unavailable>, fini=<unavailable>, rtld_fini=<unavailable>, stack_end=0x00007fffffffdb18) at libc-start.c:392:3
    frame #33: 0x000055555ac0d6e5 godot.linuxbsd.editor.dev.x86_64.llvm.mono`_start + 37

It looks like the regression was introduced by 0331ecb. cc @ajreckof