Never mind, it appears to be an issue specific to the program (Godot) I am using to embed ECL. I saw that EQL uses a similar boot signature and it works fine. I ran it under MSVC debugger with symbols and I see that the class that has the issue belongs to the project.
For those interested:
[0] Node3DEditorViewport::_update_camera (godot\editor\plugins\node_3d_editor_plugin.cpp:548) [1] Node3DEditorViewport::_notification (godot\editor\plugins\node_3d_editor_plugin.cpp:2775) [2] Node3DEditorViewport::_notificationv (godot\editor\plugins\node_3d_editor_plugin.h:104) [3] Object::notification (godot\core\object\object.cpp:837) [4] SceneTree::_process_group (godot\scene\main\scene_tree.cpp:951) [5] SceneTree::_process (godot\scene\main\scene_tree.cpp:1028) [6] SceneTree::process (godot\scene\main\scene_tree.cpp:510) [7] Main::iteration (godot\main\main.cpp:3678) [8] OS_Windows::run (godot\platform\windows\os_windows.cpp:1474) [9] widechar_main (godot\platform\windows\godot_windows.cpp:180) [10] _main (godot\platform\windows\godot_windows.cpp:204) [11] main (godot\platform\windows\godot_windows.cpp:218) [12] WinMain (godot\platform\windows\godot_windows.cpp:232) [13] __scrt_common_main_seh (D:\a_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288)
I've found that even though the EditorCamera crashes on cl_boot, the in-game Camera continues to work just fine. If I delay booting until the start of the child program, there are no issues.
I may look into the EditorCamera issue some more since it'd be convenient to use CL in the editor, but this is not an ECL issue. Sorry for the noise.
Thanks, Jason Chandler