Would appreciate some help figuring out the cause of recent engine crashes

Development Programming & Scripting
1

As of today I have been receiving many engine crashes whilst testing my game. I cant put my finger on the cause of it as they appear to happen randomly. I also lack the knowledge to interoperate the error log.

When the engine crashes, i get this message:

Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x000001fb763d50d8

PhysX3CommonPROFILE_x64!physx::Gu::TriangleMesh::getTriangleMaterialIndex() [d:\build\++fortnite\sync\engine\source\thirdparty\physx3\physx_3.4\source\geomutils\src\mesh\gutrianglemesh.h:97]
PhysX3PROFILE_x64!physx::NpShape::getMaterialFromInternalFaceIndex() [d:\build\++fortnite\sync\engine\source\thirdparty\physx3\physx_3.4\source\physx\src\npshape.cpp:464]
UE4Editor_Engine
APEXFrameworkPROFILE_x64!nvidia::apex::ApexSceneUserNotify::onContact() [d:\build\++fortnite\sync\engine\source\thirdparty\physx3\apex_1.4\framework\src\apexsceneusernotify.cpp:235]
PhysX3PROFILE_x64!physx::Sc::Scene::fireQueuedContactCallbacks() [d:\build\++fortnite\sync\engine\source\thirdparty\physx3\physx_3.4\source\simulationcontroller\src\scscene.cpp:4387]
PhysX3PROFILE_x64!physx::NpScene::fetchResults() [d:\build\++fortnite\sync\engine\source\thirdparty\physx3\physx_3.4\source\physx\src\npscene.cpp:2325]
APEXFrameworkPROFILE_x64!nvidia::apex::ApexScene::fetchResults() [d:\build\++fortnite\sync\engine\source\thirdparty\physx3\apex_1.4\framework\src\apexscene.cpp:1377]
UE4Editor_Engine
UE4Editor_Engine
UE4Editor_Engine
UE4Editor_Core
UE4Editor_Core
UE4Editor_Core
UE4Editor_Engine
UE4Editor_Engine
UE4Editor_Engine
UE4Editor_Engine
UE4Editor_Engine
UE4Editor
UE4Editor
UE4Editor
UE4Editor
UE4Editor
UE4Editor
kernel32
ntdll

And the bottom of the log it creates in saved/logs says this:

[2022.03.18-21.19.52:646][125]LogWindows: Error: === Critical error: ===
[2022.03.18-21.19.52:646][125]LogWindows: Error: 
[2022.03.18-21.19.52:646][125]LogWindows: Error: Fatal error!
[2022.03.18-21.19.52:646][125]LogWindows: Error: 
[2022.03.18-21.19.52:646][125]LogWindows: Error: Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x000001fb763d50d8
[2022.03.18-21.19.52:646][125]LogWindows: Error: 
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8bf9bc5cb PhysX3CommonPROFILE_x64.dll!physx::Gu::TriangleMesh::getTriangleMaterialIndex() [d:\build\++fortnite\sync\engine\source\thirdparty\physx3\physx_3.4\source\geomutils\src\mesh\gutrianglemesh.h:97]
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8bf58993c PhysX3PROFILE_x64.dll!physx::NpShape::getMaterialFromInternalFaceIndex() [d:\build\++fortnite\sync\engine\source\thirdparty\physx3\physx_3.4\source\physx\src\npshape.cpp:464]
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8cf5e1ca4 UE4Editor-Engine.dll!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8bf3d2794 APEXFrameworkPROFILE_x64.dll!nvidia::apex::ApexSceneUserNotify::onContact() [d:\build\++fortnite\sync\engine\source\thirdparty\physx3\apex_1.4\framework\src\apexsceneusernotify.cpp:235]
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8bf68a434 PhysX3PROFILE_x64.dll!physx::Sc::Scene::fireQueuedContactCallbacks() [d:\build\++fortnite\sync\engine\source\thirdparty\physx3\physx_3.4\source\simulationcontroller\src\scscene.cpp:4387]
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8bf56ca69 PhysX3PROFILE_x64.dll!physx::NpScene::fetchResults() [d:\build\++fortnite\sync\engine\source\thirdparty\physx3\physx_3.4\source\physx\src\npscene.cpp:2325]
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8bf3c92f8 APEXFrameworkPROFILE_x64.dll!nvidia::apex::ApexScene::fetchResults() [d:\build\++fortnite\sync\engine\source\thirdparty\physx3\apex_1.4\framework\src\apexscene.cpp:1377]
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8cf5d6bf0 UE4Editor-Engine.dll!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8cf5b827e UE4Editor-Engine.dll!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8cef79163 UE4Editor-Engine.dll!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8d17b2398 UE4Editor-Core.dll!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8d17b269a UE4Editor-Core.dll!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8d17b2963 UE4Editor-Core.dll!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8cfa19173 UE4Editor-Engine.dll!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8cfa1faba UE4Editor-Engine.dll!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8cf10349f UE4Editor-Engine.dll!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8cf10ea7b UE4Editor-Engine.dll!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff8ceedf56c UE4Editor-Engine.dll!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff7139187a0 UE4Editor.exe!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff713930fcc UE4Editor.exe!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff7139310ba UE4Editor.exe!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff7139340dd UE4Editor.exe!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff713945984 UE4Editor.exe!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff71394853a UE4Editor.exe!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff953647034 KERNEL32.DLL!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: [Callstack] 0x00007ff9555c2651 ntdll.dll!UnknownFunction []
[2022.03.18-21.19.52:646][125]LogWindows: Error: 
[2022.03.18-21.19.52:648][125]LogExit: Executing StaticShutdownAfterError
[2022.03.18-21.19.52:651][125]LogPhysicsCore: Error: PHYSX: (D:\Build\++Fortnite\Sync\Engine\Source\ThirdParty\PhysX3\PhysX_3.4\Source\PhysX\src\NpScene.cpp 238) eINVALID_OPERATION : PxScene::release(): Scene is still being simulated! PxScene::fetchResults() is called implicitly.
[2022.03.18-21.19.52:651][125]LogOutputDevice: Warning: 

Script Stack (0 frames):

[2022.03.18-21.19.52:651][125]LogWindows: Error: Error reentered: Fatal error: [File:D:/Build/++UE4/Sync/Engine/Source/Runtime/Core/Private/Windows/WindowsPlatformMisc.cpp] [Line: 475] 
Pure virtual function being called



[2022.03.18-21.19.52:651][125]LogWindows: Error: HandleError re-entered.
[2022.03.18-21.19.52:651][125]LogWindows: FPlatformMisc::RequestExit(1)
[2022.03.18-21.19.52:651][125]LogWindows: FPlatformMisc::RequestExitWithStatus(1, 3)
[2022.03.18-21.19.52:651][125]LogCore: Engine exit requested (reason: Win RequestExit)
[2022.03.18-21.19.52:659][125]Log file closed, 03/18/22 21:19:52

I can only assume it has something to do with me messing around with different physical materials, as that it something I have been doing today.

I appreciate any help that can be given to me. Thanks!

2

It looks like getTriangleMaterialIndex might be being passed a bad index.
Is there any code you can put before this to make sure you’ve allocated the array and that the index value passed in the correct range?

3

Ha im gonna be honest and say that 90% of this text sounds like a foreign language to me. xD

I work 100% with blueprints, and I have 0 clue what “getTriangleMaterialIndex” is.

All i have done today is add a new surface type into my project settings, and used a few new physical materials in my levels that use the new surface type.

4

Make sure you’re setting up your materials and physics correctly. I don’t deal with that area but it may require some type of initializing. Check the documentation.

5

I have been working on and off the project now for 3-4 years and as far as I can tell nothing has changed as far as how I handle physics and materials. I’m not sure if its relevant, but I also very recently made the switch from UE4.25 to UE4.27.

Given the errors, is it possible to determine a specific blueprint note that I am calling to cause the error, or perhaps a variable that I am trying to access that is causing it?

6

Sounds like there were changes of some sort between versions of Unreal. Try bypassing physics-related code one by one to narrow down the crash. and check the latest docs.