Syncing changes in multi-user editing tool results in crash

When using the multi-user editing tool inside a 4.24 project, persisting changes will sometimes result in a crash. 

 

 

Unable to reproduce the issue. However, the user has reported occasionally receiving the crash and only when using the multi-user editing tool and a member in the session clicks persist changes. 

 

Tested in: 4.22.3 CL#7053642 4.23.1 CL#9631420 4.25 CL#10730208

1. Set up Multi User Editing for a 4.24 project

2. Edit or make changes to the level

3. Click Persist Changes

Result: User's engine crashes

Expected: Successfully persist changes

Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 614] Array index out of bounds: 13 from an array of size 13

 

UE4Editor_Core!AssertFailedImplV() [d:\build\++ue4\sync\engine\source\runtime\core\private\misc\assertionmacros.cpp:105]

UE4Editor_Core!FDebug::CheckVerifyFailedImpl() [d:\build\++ue4\sync\engine\source\runtime\core\private\misc\assertionmacros.cpp:455]

UE4Editor_MultiUserClient!DispatchCheckVerify<void,<lambda_9fce306d35cea46c3a0fa7a0504b1cc2> >() [d:\build\++ue4\sync\engine\source\runtime\core\public\misc\assertionmacros.h:168]

UE4Editor_MultiUserClient!FConcertWorkspaceUI::PromptPersistSessionChanges() [d:\build\++ue4\sync\engine\plugins\developer\concert\multiuserclient\source\multiuserclient\private\concertworkspaceui.cpp:614]

UE4Editor_MultiUserClient!TBaseFunctorDelegateInstance<void __cdecl(void),<lambda_671faeaeb53e620aec7ef88c7eb00bc6> >::ExecuteIfSafe() [d:\build\++ue4\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:1000]

UE4Editor_Slate!SMenuEntryBlock::OnClicked() [d:\build\++ue4\sync\engine\source\runtime\slate\private\framework\multibox\smenuentryblock.cpp:1068]

UE4Editor_Slate!SMenuEntryBlock::OnMenuItemButtonClicked() [d:\build\++ue4\sync\engine\source\runtime\slate\private\framework\multibox\smenuentryblock.cpp:1019]

UE4Editor_Slate!TBaseSPMethodDelegateInstance<0,SMenuEntryBlock,0,FReply __cdecl(void)>::Execute() [d:\build\++ue4\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:293]

UE4Editor_Slate!SButton::ExecuteOnClick() [d:\build\++ue4\sync\engine\source\runtime\slate\private\widgets\input\sbutton.cpp:385]

UE4Editor_Slate!SButton::OnMouseButtonUp() [d:\build\++ue4\sync\engine\source\runtime\slate\private\widgets\input\sbutton.cpp:304]

UE4Editor_Slate!SMenuEntryButton::OnMouseButtonUp() [d:\build\++ue4\sync\engine\source\runtime\slate\private\framework\multibox\smenuentryblock.cpp:386]

UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FToLeafmostPolicy,FPointerEvent,<lambda_6c1f6b862bcfb82ea6dcab28fbcc9463> >() [d:\build\++ue4\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:372]

UE4Editor_Slate!FSlateApplication::RoutePointerUpEvent() [d:\build\++ue4\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:4617]

UE4Editor_Slate!FSlateApplication::ProcessMouseButtonUpEvent() [d:\build\++ue4\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5140]

UE4Editor_Slate!FSlateApplication::OnMouseUp() [d:\build\++ue4\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5108]

UE4Editor_ApplicationCore!FWindowsApplication::ProcessDeferredMessage() [d:\build\++ue4\sync\engine\source\runtime\applicationcore\private\windows\windowsapplication.cpp:1958]

UE4Editor_ApplicationCore!FWindowsApplication::DeferMessage() [d:\build\++ue4\sync\engine\source\runtime\applicationcore\private\windows\windowsapplication.cpp:2410]

UE4Editor_ApplicationCore!FWindowsApplication::ProcessMessage() [d:\build\++ue4\sync\engine\source\runtime\applicationcore\private\windows\windowsapplication.cpp:1638]

UE4Editor_ApplicationCore!FWindowsApplication::AppWndProc() [d:\build\++ue4\sync\engine\source\runtime\applicationcore\private\windows\windowsapplication.cpp:789]

user32

user32

UE4Editor_ApplicationCore!FWindowsPlatformApplicationMisc::PumpMessages() [d:\build\++ue4\sync\engine\source\runtime\applicationcore\private\windows\windowsplatformapplicationmisc.cpp:130]

UE4Editor!FEngineLoop::Tick() [d:\build\++ue4\sync\engine\source\runtime\launch\private\launchengineloop.cpp:4397]

UE4Editor!GuardedMain() [d:\build\++ue4\sync\engine\source\runtime\launch\private\launch.cpp:173]

UE4Editor!GuardedMainWrapper() [d:\build\++ue4\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:134]

UE4Editor!WinMain() [d:\build\++ue4\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:263]

UE4Editor!__scrt_common_main_seh() [d:\agent\_work\2\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288]

kernel32

ntdll