Editor crash when opening and closing immediately project

[qarmin]

Godot version:
4.0.dev.custom_build.1222541c9

OS/device including version:
Ubuntu 19.10

Issue description:
When I open minimal and close project with command godot -e --quit, then editor crash with this backtrace

scene/gui/control.cpp:850:57: runtime error: member access within null pointer of type 'const struct Control'
scene/gui/control.cpp:850:57: runtime error: member call on null pointer of type 'const struct Object'
scene/gui/control.cpp:850:57: runtime error: member access within null pointer of type 'const struct Control'
scene/gui/control.cpp:850:57: runtime error: member access within null pointer of type 'const struct Control'
handle_crash: Program crashed with signal 11
Dumping the backtrace. Please include this when reporting the bug on https://github.com/godotengine/godot/issues
[1] bin/godot.linuxbsd.tools.64s() [0x1755a1a] (/mnt/KubuntuWolne/mojgodot/platform/linuxbsd/crash_handler_linuxbsd.cpp:54)
[2] /lib/x86_64-linux-gnu/libc.so.6(+0x46470) [0x7ff05164e470] (??:0)
[3] Control::get_theme_icon(StringName const&, StringName const&) const (/mnt/KubuntuWolne/mojgodot/scene/gui/control.cpp:850 (discriminator 4))
[4] EditorResourcePreview::_generate_preview(Ref<ImageTexture>&, Ref<ImageTexture>&, EditorResourcePreview::QueueItem const&, String const&) (/mnt/KubuntuWolne/mojgodot/editor/editor_resource_preview.cpp:171 (discriminator 6))
[5] EditorResourcePreview::_thread() (/mnt/KubuntuWolne/mojgodot/editor/editor_resource_preview.cpp:269)
[6] EditorResourcePreview::_thread_func(void*) (/mnt/KubuntuWolne/mojgodot/editor/editor_resource_preview.cpp:108)
[7] ThreadPosix::thread_callback(void*) (/mnt/KubuntuWolne/mojgodot/drivers/unix/thread_posix.cpp:76)
[8] /lib/x86_64-linux-gnu/libpthread.so.0(+0x9669) [0x7ff0524c9669] (??:0)
[9] /lib/x86_64-linux-gnu/libc.so.6(clone+0x43) [0x7ff05172a323] (??:0)

For now it may crash with a little different backtrace similar to #37655, until PR which will fix it will be merged.

Minimal reproduction project:
https://github.com/qarmin/The-worst-Godot-test-project/archive/master.zip

[qarmin]

This patch fixes crash, but it seems to be only a workaround

diff --git a/editor/editor_resource_preview.cpp b/editor/editor_resource_preview.cpp
index 2a4300f833..9bda1c279c 100644
--- a/editor/editor_resource_preview.cpp
+++ b/editor/editor_resource_preview.cpp
@@ -168,6 +168,9 @@ void EditorResourcePreview::_generate_preview(Ref<ImageTexture> &r_texture, Ref<
                }
                r_texture = generated;
 
+               if (!EditorNode::get_singleton()->get_theme_base())
+                       return;
+
                int small_thumbnail_size = EditorNode::get_singleton()->get_theme_base()->get_theme_icon("Object", "EditorIcons")->get_width(); // Kind of a workaround to retrieve the default icon size
                small_thumbnail_size *= EDSCALE;
 

[reduz]

I can't reproduce the crash either on X11 or Windows, is it still a problem?

[qarmin]

I can't check it now due to other recently introduced crash with LocalVector(caused due using null pointer to struct Scenario)

servers/rendering/rendering_server_scene.cpp:996:27: runtime error: member access within null pointer of type 'struct Scenario'
handle_crash: Program crashed with signal 11
Dumping the backtrace. Please include this when reporting the bug on https://github.com/godotengine/godot/issues
[1] godot4s() [0x19daa60] (/mnt/Miecz/godot/platform/linuxbsd/crash_handler_linuxbsd.cpp:54)
[2] /lib/x86_64-linux-gnu/libc.so.6(+0x46210) [0x7f65a544a210] (??:0)
[3] LocalVector<RID, unsigned int, false>::push_back(RID) (/mnt/Miecz/godot/./core/local_vector.h:57)
[4] RenderingServerScene::_update_instance(RenderingServerScene::Instance*) (/mnt/Miecz/godot/servers/rendering/rendering_server_scene.cpp:1000)
[5] RenderingServerScene::_update_dirty_instance(RenderingServerScene::Instance*) (/mnt/Miecz/godot/servers/rendering/rendering_server_scene.cpp:2919)
[6] RenderingServerScene::update_dirty_instances() (/mnt/Miecz/godot/servers/rendering/rendering_server_scene.cpp:2926)
[7] RenderingServerScene::free(RID) (/mnt/Miecz/godot/servers/rendering/rendering_server_scene.cpp:2954)
[8] RenderingServerRaster::free(RID) (/mnt/Miecz/godot/servers/rendering/rendering_server_raster.cpp:77)
[9] RenderingServerWrapMT::free(RID) (/mnt/Miecz/godot/servers/rendering/rendering_server_wrap_mt.h:663)
[10] Node3DEditor::_finish_grid() (/mnt/Miecz/godot/editor/plugins/node_3d_editor_plugin.cpp:5586 (discriminator 2))
[11] Node3DEditor::update_grid() (/mnt/Miecz/godot/editor/plugins/node_3d_editor_plugin.cpp:5592)
[12] Node3DEditorViewport::_update_camera(float) (/mnt/Miecz/godot/editor/plugins/node_3d_editor_plugin.cpp:356)
[13] Node3DEditorViewport::_notification(int) (/mnt/Miecz/godot/editor/plugins/node_3d_editor_plugin.cpp:2333)
[14] Node3DEditorViewport::_notificationv(int, bool) (/mnt/Miecz/godot/editor/plugins/node_3d_editor_plugin.h:179 (discriminator 14))
[15] Object::notification(int, bool) (/mnt/Miecz/godot/core/object.cpp:901)
[16] CanvasItem::_propagate_visibility_changed(bool) (/mnt/Miecz/godot/scene/main/canvas_item.cpp:364)
[17] CanvasItem::_propagate_visibility_changed(bool) (/mnt/Miecz/godot/scene/main/canvas_item.cpp:371 (discriminator 2))
[18] CanvasItem::_propagate_visibility_changed(bool) (/mnt/Miecz/godot/scene/main/canvas_item.cpp:371 (discriminator 2))
[19] CanvasItem::_propagate_visibility_changed(bool) (/mnt/Miecz/godot/scene/main/canvas_item.cpp:371 (discriminator 2))
[20] CanvasItem::_propagate_visibility_changed(bool) (/mnt/Miecz/godot/scene/main/canvas_item.cpp:371 (discriminator 2))
[21] CanvasItem::show() (/mnt/Miecz/godot/scene/main/canvas_item.cpp:395)
[22] Node3DEditorPlugin::make_visible(bool) (/mnt/Miecz/godot/editor/plugins/node_3d_editor_plugin.cpp:6395)
[23] EditorNode::_editor_select(int) (/mnt/Miecz/godot/editor/editor_node.cpp:2869)
[24] EditorNode::_notification(int) (/mnt/Miecz/godot/editor/editor_node.cpp:552)
[25] EditorNode::_notificationv(int, bool) (/mnt/Miecz/godot/editor/editor_node.h:91 (discriminator 14))
[26] Object::notification(int, bool) (/mnt/Miecz/godot/core/object.cpp:901)
[27] Node::_propagate_ready() (/mnt/Miecz/godot/scene/main/node.cpp:191)
[28] Node::_propagate_ready() (/mnt/Miecz/godot/scene/main/node.cpp:181 (discriminator 2))
[29] Node::_set_tree(SceneTree*) (/mnt/Miecz/godot/scene/main/node.cpp:2563)
[30] SceneTree::init() (/mnt/Miecz/godot/scene/main/scene_tree.cpp:404)
[31] OS_LinuxBSD::run() (/mnt/Miecz/godot/platform/linuxbsd/os_linuxbsd.cpp:233)
[32] godot4s(main+0x326) [0x19d882c] (/mnt/Miecz/godot/platform/linuxbsd/godot_linuxbsd.cpp:57)
[33] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf3) [0x7f65a542b0b3] (??:0)
[34] godot4s(_start+0x2e) [0x19d844e] (??:?)

[qarmin]

This also happens with Godot 3.2.3 beta 1

The best way to reproduce it is to clone godot-demo-project repo, and then open every single project inside editor:

DRI_PRIME=0 godot -e -q --path "/home/rafal/Projekty Dzikie/godot-demo-projects/gui/translation"
DRI_PRIME=0 godot -e -q --path "/home/rafal/Projekty Dzikie/godot-demo-projects/gui/rich_text_bbcode"
DRI_PRIME=0 godot -e -q --path "/home/rafal/Projekty Dzikie/godot-demo-projects/plugins"
DRI_PRIME=0 godot -e -q --path "/home/rafal/Projekty Dzikie/godot-demo-projects/mobile/multitouch_cubes"
DRI_PRIME=0 godot -e -q --path "/home/rafal/Projekty Dzikie/godot-demo-projects/mobile/sensors"
DRI_PRIME=0 godot -e -q --path "/home/rafal/Projekty Dzikie/godot-demo-projects/mobile/multitouch_view"
DRI_PRIME=0 godot -e -q --path "/home/rafal/Projekty Dzikie/godot-demo-projects/mobile/android_iap"
DRI_PRIME=0 godot -e -q --path "/home/rafal/Projekty Dzikie/godot-demo-projects/3d/voxel"
DRI_PRIME=0 godot -e -q --path "/home/rafal/Projekty Dzikie/godot-demo-projects/3d/platformer"
DRI_PRIME=0 godot -e -q --path "/home/rafal/Projekty Dzikie/godot-demo-projects/3d/ik"
DRI_PRIME=0 godot -e -q --path "/home/rafal/Projekty Dzikie/godot-demo-projects/3d/physics_tests"
DRI_PRIME=0 godot -e -q --path "/home/rafal/Projekty Dzikie/godot-demo-projects/3d/material_testers"
DRI_PRIME=0 godot -e -q --path "/home/rafal/Projekty Dzikie/godot-demo-projects/3d/truck_town"
DRI_PRIME=0 godot -e -q --path "/home/rafal/Projekty Dzikie/godot-demo-projects/3d/kinematic_character"

[qarmin]

Looks that this may be fixed already, since I didn't have any crashes recently(~1 year)