This is a somewhat common crash that appears to occur only in 4.17.1 (possible regression?). Users have not provided any description of their actions when the crash occurs.
Source Context
20 TArray<float> Scores; 21 22 void ResetScore(int32 NewCount) 23 { 24 Scores.Reset(NewCount); 25 Scores.AddZeroed(NewCount); 26 } 27 28 void SetScore(int32 Index, float NewScore) 29 { 30 ***** Scores[Index] = NewScore; 31 } 32 33 float GetScore(int32 Index) const 34 { 35 return Scores[Index]; 36 }
Result: Crash
Assertion failed: (Index >= 0) & (Index < ArrayNum) [File:D:\Build\++UE4+Release-4.17+Compile\Sync\Engine\Source\Runtime\Core\Public\Containers/Array.h] [Line: 596] Array index out of bounds: -1 from an array of size 1 UE4Editor_Persona!FBoneDescription::SetScore() [bonemappinghelper.h:31] UE4Editor_Persona!FBoneMappingHelper::TryMatch() [bonemappinghelper.cpp:273] UE4Editor_Persona!SRigWindow::OnAutoMapping() [srigwindow.cpp:355] UE4Editor_Persona!TMemberFunctionCaller<SRigWindow,FReply() [delegateinstanceinterface.h:165] UE4Editor_Persona!UE4Tuple_Private::TTupleImpl<TIntegerSequence<unsigned int> >::ApplyAfter<TMemberFunctionCaller<SRigWindow,FReply() [tuple.h:497] UE4Editor_Persona!TBaseSPMethodDelegateInstance<0,SRigWindow,0,FReply __cdecl() [delegateinstancesimpl.h:327] UE4Editor_Slate!TBaseDelegate<FReply>::Execute() [delegatesignatureimpl.inl:537] UE4Editor_Slate!SButton::OnMouseButtonUp() [sbutton.cpp:282] UE4Editor_Slate!<lambda_1002768c627006711ef2f351a87ec0e7>::operator() [slateapplication.cpp:5199] UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FToLeafmostPolicy,FPointerEvent,<lambda_1002768c627006711ef2f351a87ec0e7> >() [slateapplication.cpp:232] UE4Editor_Slate!FSlateApplication::RoutePointerUpEvent() [slateapplication.cpp:5188] UE4Editor_Slate!FSlateApplication::ProcessMouseButtonUpEvent() [slateapplication.cpp:5690] UE4Editor_Slate!FSlateApplication::OnMouseUp() [slateapplication.cpp:5670] UE4Editor_Core!FWindowsApplication::ProcessDeferredMessage() [windowsapplication.cpp:1718] UE4Editor_Core!FWindowsApplication::DeferMessage() [windowsapplication.cpp:2161] UE4Editor_Core!FWindowsApplication::ProcessMessage() [windowsapplication.cpp:881] UE4Editor_Core!FWindowsApplication::AppWndProc() [windowsapplication.cpp:721] user32!UserCallWinProcCheckWow() user32!DispatchMessageWorker() UE4Editor_Core!FWindowsPlatformMisc::PumpMessages() [windowsplatformmisc.cpp:1009] UE4Editor!FEngineLoop::Tick() [launchengineloop.cpp:3151] UE4Editor!GuardedMain() [launch.cpp:166] UE4Editor!GuardedMainWrapper() [launchwindows.cpp:134] UE4Editor!WinMain() [launchwindows.cpp:210] UE4Editor!__scrt_common_main_seh() [exe_common.inl:253] kernel32!BaseThreadInitThunk() ntdll!RtlUserThreadStart()
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-49771 in the post.