Unreal Engine Issues and Bug Tracker (UE-50877)

Description

When a breakpoint is hit in a BT Task, if you attempt to use CTRL+P to search for and open the BT the task is being run in, try to resume execution, and then return to the original BT Task Blueprint and Pause and Resume execution there, it will cause the editor to crash.

Found in 4.17.2 CL# 3658906

Reproduced in 4.16.3 CL# 3561208 & 4.18 Preview 3 CL# 3676890

Steps to Reproduce

Open the attached project
Open BTT_MoveToLocation
Press Play to begin execution and hit the breakpoint
Press CTRL+P and search for AI_BT, then hit enter to open it
Press Resume to resume the execution of the BT
Go back to the BTTask, and hit Pause and then Resume.

Result: Editor crashes

Callstack

[2017.10.06-13.05.17:691][282]LogWindows: Error: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 610]
[2017.10.06-13.05.17:691][282]LogWindows: Error: Array index out of bounds: -1 from an array of size 0

0x00000000D5C33C58 KERNELBASE.dll!UnknownFunction []
0x00000000B65876D4 UE4Editor-ApplicationCore.dll!FWindowsErrorOutputDevice::Serialize() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\applicationcore\private\windows\windowserroroutputdevice.cpp:65]
0x0000000099D52EBB UE4Editor-Core.dll!FOutputDevice::Logf__VA() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\core\private\misc\outputdevice.cpp:70]
0x0000000099CE6059 UE4Editor-Core.dll!FDebug::AssertFailed() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\core\private\misc\assertionmacros.cpp:414]
0x0000000092C24D46 UE4Editor-AIModule.dll!UBehaviorTreeComponent::UpdateDebuggerAfterExecution() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\aimodule\private\behaviortree\behaviortreecomponent.cpp:2403]
0x0000000092BE9E5C UE4Editor-AIModule.dll!UBehaviorTreeComponent::ExecuteTask() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\aimodule\private\behaviortree\behaviortreecomponent.cpp:1517]
0x0000000092C08D1A UE4Editor-AIModule.dll!UBehaviorTreeComponent::ProcessExecutionRequest() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\aimodule\private\behaviortree\behaviortreecomponent.cpp:1334]
0x0000000092C21405 UE4Editor-AIModule.dll!UBehaviorTreeComponent::TickComponent() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\aimodule\private\behaviortree\behaviortreecomponent.cpp:1064]
0x000000008FE620F7 UE4Editor-Engine.dll!FActorComponentTickFunction::ExecuteTickHelper<<lambda_00d9c935eb8c907965991feb76bc5b0f> >() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\engine\classes\gameframework\actor.h:3100]
0x000000008FE9D3A4 UE4Editor-Engine.dll!FActorComponentTickFunction::ExecuteTick() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\engine\private\components\actorcomponent.cpp:794]
0x0000000090AC41DB UE4Editor-Engine.dll!FTickFunctionTask::DoTask() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\engine\private\ticktaskmanager.cpp:273]
0x0000000090AC923B UE4Editor-Engine.dll!TGraphTask<FTickFunctionTask>::ExecuteTask() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\core\public\async\taskgraphinterfaces.h:784]
0x0000000099BB4895 UE4Editor-Core.dll!FNamedTaskThread::ProcessTasksNamedThread() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\core\private\async\taskgraph.cpp:651]
0x0000000099BB4B90 UE4Editor-Core.dll!FNamedTaskThread::ProcessTasksUntilIdle() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\core\private\async\taskgraph.cpp:571]
0x0000000090AE5961 UE4Editor-Engine.dll!FTickTaskSequencer::ReleaseTickGroup() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\engine\private\ticktaskmanager.cpp:559]
0x0000000090AEB572 UE4Editor-Engine.dll!FTickTaskManager::RunTickGroup() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\engine\private\ticktaskmanager.cpp:1454]
0x00000000903CCAF4 UE4Editor-Engine.dll!UWorld::RunTickGroup() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\engine\private\leveltick.cpp:760]
0x00000000903D5E33 UE4Editor-Engine.dll!UWorld::Tick() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\engine\private\leveltick.cpp:1420]
0x0000000094E56573 UE4Editor-UnrealEd.dll!UEditorEngine::Tick() [d:\unrealengine-4.18.0-preview-3\engine\source\editor\unrealed\private\editorengine.cpp:1659]
0x000000009571B396 UE4Editor-UnrealEd.dll!UUnrealEdEngine::Tick() [d:\unrealengine-4.18.0-preview-3\engine\source\editor\unrealed\private\unrealedengine.cpp:396]
 0x0000000074B05A26 UE4Editor.exe!FEngineLoop::Tick() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\launch\private\launchengineloop.cpp:3296]
0x0000000074B15430 UE4Editor.exe!GuardedMain() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\launch\private\launch.cpp:166]
 0x0000000074B154AA UE4Editor.exe!GuardedMainWrapper() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\launch\private\windows\launchwindows.cpp:134]
0x0000000074B22379 UE4Editor.exe!WinMain() [d:\unrealengine-4.18.0-preview-3\engine\source\runtime\launch\private\windows\launchwindows.cpp:210]
0x0000000074B23D57 UE4Editor.exe!__scrt_common_main_seh() [f:\dd\vctools\crt\vcstartup\src\startup\exe_common.inl:253]
0x00000000D71C8364 KERNEL32.DLL!UnknownFunction []
0x00000000D9057091 ntdll.dll!UnknownFunction []
0x00000000D9057091 ntdll.dll!UnknownFunction []

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Cannot Reproduce

Component	UE - Gameplay
Affects Versions	4.16, 4.17, 4.18
Target Fix	4.19

Created	Oct 6, 2017
Resolved	Feb 3, 2018
Updated	Apr 27, 2018

UE-50877

Crash Occurs When Attempting to Resume Execution After Hitting a Breakpoint in a BT Task

Crash Occurs When Attempting to Resume Execution After Hitting a Breakpoint in a BT Task

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