UnkownFunction - EXCEPTION_ACCESS_VIOLATION 0x0000000000000000

Hey!

I’m pretty at coding C++ in Unreal.
Currently I’m writing a Blueprint Component in C++ to generate Footstep Sounds and Decals.
For some reason, UE5 crashes to the desktop after like 2 Minutes when starting the game.

The weird thing is, that my stack looks like this:

[2023.01.10-17.21.59:065][547]LogWindows: Error: === Critical error: ===
[2023.01.10-17.21.59:065][547]LogWindows: Error:
[2023.01.10-17.21.59:065][547]LogWindows: Error: Unhandled Exception: EXCEPTION_ACCESS_VIOLATION 0x0000000000000000
[2023.01.10-17.21.59:065][547]LogWindows: Error:
[2023.01.10-17.21.59:065][547]LogWindows: Error: [Callstack] 0x0000000000000000 UnknownFunction []
[2023.01.10-17.21.59:065][547]LogWindows: Error: [Callstack] 0x00007ffb0913d7fc UnrealEditor-Engine.dll!UnknownFunction []
[2023.01.10-17.21.59:065][547]LogWindows: Error: [Callstack] 0x00007ffb0919cdca UnrealEditor-Engine.dll!UnknownFunction []
[2023.01.10-17.21.59:065][547]LogWindows: Error: [Callstack] 0x00007ffb08129003 UnrealEditor-Engine.dll!UnknownFunction []
[2023.01.10-17.21.59:065][547]LogWindows: Error: [Callstack] 0x00007ffb04a4e5f5 UnrealEditor-UnrealEd.dll!UnknownFunction []
[2023.01.10-17.21.59:065][547]LogWindows: Error: [Callstack] 0x00007ffb053daac6 UnrealEditor-UnrealEd.dll!UnknownFunction []
[2023.01.10-17.21.59:065][547]LogWindows: Error: [Callstack] 0x00007ff6ed7982f6 UnrealEditor.exe!UnknownFunction []
[2023.01.10-17.21.59:065][547]LogWindows: Error: [Callstack] 0x00007ff6ed7b0d9c UnrealEditor.exe!UnknownFunction []
[2023.01.10-17.21.59:065][547]LogWindows: Error: [Callstack] 0x00007ff6ed7b0e8a UnrealEditor.exe!UnknownFunction []
[2023.01.10-17.21.59:065][547]LogWindows: Error: [Callstack] 0x00007ff6ed7b3c4d UnrealEditor.exe!UnknownFunction []
[2023.01.10-17.21.59:065][547]LogWindows: Error: [Callstack] 0x00007ff6ed7c5564 UnrealEditor.exe!UnknownFunction []
[2023.01.10-17.21.59:065][547]LogWindows: Error: [Callstack] 0x00007ff6ed7c8736 UnrealEditor.exe!UnknownFunction []
[2023.01.10-17.21.59:065][547]LogWindows: Error: [Callstack] 0x00007ffbb43b26bd KERNEL32.DLL!UnknownFunction []
[2023.01.10-17.21.59:065][547]LogWindows: Error: [Callstack] 0x00007ffbb4d4dfb8 ntdll.dll!UnknownFunction []
[2023.01.10-17.21.59:065][547]LogWindows: Error:
[2023.01.10-17.21.59:068][547]LogExit: Executing StaticShutdownAfterError
[2023.01.10-17.21.59:070][547]LogWindows: FPlatformMisc::RequestExit(1)
[2023.01.10-17.21.59:070][547]LogWindows: FPlatformMisc::RequestExitWithStatus(1, 3)
[2023.01.10-17.21.59:070][547]LogCore: Engine exit requested (reason: Win RequestExit)
[2023.01.10-17.21.59:079][547]Log file closed, 01/10/23 18:21:59

I don’t even have a starting point where to look for an error… since it’s all “unknown function” and an exception at 0x000000000

Could this have something to do with garbage collection or anything?
Is there a way to get a better log out of UE5?

Any help is appreciated!
Thanks!
Ron

0x000000000 means it’s a null pointer exception.
You are trying to access a reference that was either never set or as you suspect could have been garbage collected.

Make sure that important variables referenced in classes have the macro UPROPERTY() above them. This stops the engine from garbage collecting them.

Also look in your SAVED directory for any logs regarding the crash. It may shed some light on what variable is triggering the exception.

Hey!
Thanks for the reply!

I’m using UPROPERTY() on all class properties already to make sure nothing gets garbage collected. Plus I made sure I check every variable for nullptr before accessing it.

Still the engine crashes after some time.
My code works nice before the crash though - everything behaves like expected.

That’s why I thought something might get GC’ed.

You mentioned the SAVED folder - I usually check the log files in the LOGS folder for crash reports. Is there some other file/folder that could shed some light on the crash?

Thanks!

Well the folder structure for logs is usualy
ProjectName => Saved => Logs

Ok, thanks - that’s where I’m checking for log files.
So nothing more to see there :frowning: