Description

Crash when attempting to generate an event in an Event Handler

Steps to Reproduce
  1. Create and open a new Fountain System
  2. In Emitter Properties, enable Requires Persistent IDs
  3. Duplicate the Emitter
  4. In the original Emitters Particle Update, add a Generate Location or Generate Death Event module
  5. Add an Event Handler to the duplicate Emitter
  6. Set the Event Handler's Source to the generated event
  7. Add a Generate Location Event or Generate Death module to the Event Handler
  8. Wait a second

Result: Editor crashes

Callstack
Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x00000000

UE4Editor_VectorVM!FBatchedWriteIndexedOutput::DoRegisterKernelFixedValid<FBatchedWriteIndexedOutput::FCopyOp>() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\VectorVM\Private\VectorVM.cpp:2580]
UE4Editor_VectorVM!<lambda_5cc799fc87ee9eaf015cfd69ea4c3fc2>::operator()() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\VectorVM\Private\VectorVM.cpp:2319]
UE4Editor_VectorVM!VectorVM::Exec() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\VectorVM\Private\VectorVM.cpp:2460]
UE4Editor_Niagara!FNiagaraScriptExecutionContext::Execute() [D:\Build\++UE4+Licensee\Sync\Engine\Plugins\FX\Niagara\Source\Niagara\Private\NiagaraScriptExecutionContext.cpp:217]
UE4Editor_Niagara!FNiagaraEmitterInstance::Tick() [D:\Build\++UE4+Licensee\Sync\Engine\Plugins\FX\Niagara\Source\Niagara\Private\NiagaraEmitterInstance.cpp:1717]
UE4Editor_Niagara!FNiagaraSystemInstance::Tick_Concurrent() [D:\Build\++UE4+Licensee\Sync\Engine\Plugins\FX\Niagara\Source\Niagara\Private\NiagaraSystemInstance.cpp:2076]
UE4Editor_Niagara!FNiagaraSystemSimulation::FlushTickBatch() [D:\Build\++UE4+Licensee\Sync\Engine\Plugins\FX\Niagara\Source\Niagara\Private\NiagaraSystemSimulation.cpp:614]
UE4Editor_Niagara!FNiagaraSystemSimulation::Tick_Concurrent() [D:\Build\++UE4+Licensee\Sync\Engine\Plugins\FX\Niagara\Source\Niagara\Private\NiagaraSystemSimulation.cpp:1103]
UE4Editor_Niagara!FNiagaraSystemSimulation::Tick_GameThread() [D:\Build\++UE4+Licensee\Sync\Engine\Plugins\FX\Niagara\Source\Niagara\Private\NiagaraSystemSimulation.cpp:848]
UE4Editor_Niagara!FNiagaraSystemInstance::ComponentTick() [D:\Build\++UE4+Licensee\Sync\Engine\Plugins\FX\Niagara\Source\Niagara\Private\NiagaraSystemInstance.cpp:1915]
UE4Editor_Niagara!UNiagaraComponent::TickComponent() [D:\Build\++UE4+Licensee\Sync\Engine\Plugins\FX\Niagara\Source\Niagara\Private\NiagaraComponent.cpp:620]
UE4Editor_Engine!FActorComponentTickFunction::ExecuteTickHelper<<lambda_a11669b3e3f4a9399f884e36456a23d1> >() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Engine\Classes\GameFramework\Actor.h:3471]
UE4Editor_Engine!FActorComponentTickFunction::ExecuteTick() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Engine\Private\Components\ActorComponent.cpp:976]
UE4Editor_Engine!FTickFunctionTask::DoTask() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Engine\Private\TickTaskManager.cpp:283]
UE4Editor_Engine!TGraphTask<FTickFunctionTask>::ExecuteTask() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Core\Public\Async\TaskGraphInterfaces.h:849]
UE4Editor_Core!FNamedTaskThread::ProcessTasksNamedThread() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Core\Private\Async\TaskGraph.cpp:692]
UE4Editor_Core!FNamedTaskThread::ProcessTasksUntilQuit() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Core\Private\Async\TaskGraph.cpp:587]
UE4Editor_Core!FTaskGraphImplementation::WaitUntilTasksComplete() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Core\Private\Async\TaskGraph.cpp:1478]
UE4Editor_Engine!FTickTaskSequencer::ReleaseTickGroup() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Engine\Private\TickTaskManager.cpp:558]
UE4Editor_Engine!FTickTaskManager::RunTickGroup() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Engine\Private\TickTaskManager.cpp:1523]
UE4Editor_Engine!UWorld::RunTickGroup() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Engine\Private\LevelTick.cpp:783]
UE4Editor_Engine!UWorld::Tick() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Engine\Private\LevelTick.cpp:1558]
UE4Editor_NiagaraEditor!FNiagaraSystemViewportClient::Tick() [D:\Build\++UE4+Licensee\Sync\Engine\Plugins\FX\Niagara\Source\NiagaraEditor\Private\Widgets\SNiagaraSystemViewport.cpp:98]
UE4Editor_UnrealEd!UEditorEngine::Tick() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Editor\UnrealEd\Private\EditorEngine.cpp:1770]
UE4Editor_UnrealEd!UUnrealEdEngine::Tick() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Editor\UnrealEd\Private\UnrealEdEngine.cpp:414]
UE4Editor!FEngineLoop::Tick() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Launch\Private\LaunchEngineLoop.cpp:4850]
UE4Editor!GuardedMain() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Launch\Private\Launch.cpp:169]
UE4Editor!GuardedMainWrapper() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:137]
UE4Editor!WinMain() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:268]
UE4Editor!__scrt_common_main_seh() [d:\agent\_work\5\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288]
kernel32
ntdll

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Fixed
ComponentUE - Niagara
Affects Versions4.25
Target Fix5.0
Fix Commit18658620
Main Commit18658679
Release Commit18658620
CreatedMay 27, 2020
ResolvedJan 19, 2022
UpdatedJan 26, 2023
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