Crash on exit

[kring]

I frequently see a crash on exit. This is the call stack:

>	[Inline Frame] UnrealEditor-CesiumEditor.dll!FCesiumGeoreferenceCustomization::Unregister(FPropertyEditorModule &) Line 20	C++
 	[Inline Frame] UnrealEditor-CesiumEditor.dll!?A0x82102606::unregisterDetailCustomization() Line 130	C++
 	UnrealEditor-CesiumEditor.dll!FCesiumEditorModule::ShutdownModule() Line 391	C++
 	[Inline Frame] UnrealEditor-Core.dll!FModuleManager::UnloadModule(const FName) Line 686	C++
 	UnrealEditor-Core.dll!FModuleManager::UnloadModulesAtShutdown() Line 816	C++
 	UnrealEditor.exe!FEngineLoop::Exit() Line 4650	C++
 	[Inline Frame] UnrealEditor.exe!EngineExit() Line 77	C++
 	[Inline Frame] UnrealEditor.exe!GuardedMain::__l2::EngineLoopCleanupGuard::{dtor}() Line 131	C++
 	UnrealEditor.exe!GuardedMain(const wchar_t * CmdLine) Line 216	C++
 	UnrealEditor.exe!LaunchWindowsStartup(HINSTANCE__ * hInInstance, HINSTANCE__ * hPrevInstance, char * __formal, int nCmdShow, const wchar_t * CmdLine) Line 233	C++
 	UnrealEditor.exe!WinMain(HINSTANCE__ * hInInstance, HINSTANCE__ * hPrevInstance, char * pCmdLine, int nCmdShow) Line 282	C++
 	[Inline Frame] UnrealEditor.exe!invoke_main() Line 102	C++
 	UnrealEditor.exe!__scrt_common_main_seh() Line 288	C++
 	kernel32.dll!00007ffc17c2257d()	Unknown
 	ntdll.dll!00007ffc1900aa58()	Unknown

It's an access violation that looks like this:

Exception thrown: read access violation.
**__imp_ACesiumGeoreference::GetPrivateStaticClass**(...) returned 0x21364955F50.

So we're unloading the CesiumEditor module, and apparently ACesiumGeoreference::StaticClass() is returning an invalid pointer. Based on the Unreal log, it doesn't look like the CesiumRuntime module was unloaded first, so I don't really know why that pointer would be invalid.

[kring]

I've seen this in multiple branches, so I'm fairly certain whatever caused it is already in main.

[csciguy8]

I see this when running out of this new branch to support UE 5.4, and running in UE 5.4

Running attached to MSVS, DebugGame build. Just opening cesium-unreal-samples, level 01, then closing after a few moments.