The following sequence leads to a crash in 4.5. Removing the relative scale call does not lead to a crash :
Actor->GetRootPrimitiveComponent()->SetSimulatePhysics(false);
Actor->GetRootComponent()->AttachTo(this, NAME_None, EAttachLocation::KeepWorldPosition);
Actor->SetActorRelativeScale3D(FVector(0.1f, 0.1f, 0.1f));
After more playing around, found that the EAttachLocation::SnapToTarget produces the same crash even when not using a Scale.
Here’s the full debug engine build’s stacktrace:
PhysX3PROFILE_x64.dll!00007ff982cea320() Unknown
PhysX3PROFILE_x64.dll!00007ff982c6a3f2() Unknown
UE4Editor-Engine-Win64-Debug.dll!TGraphTask<FPhysXTask>::ExecuteTask(TArray<FBaseGraphTask *,FDefaultAllocator> & NewTasks, ENamedThreads::Type CurrentThread) Line 656 C++
UE4Editor-Core-Win64-Debug.dll!FBaseGraphTask::Execute(TArray<FBaseGraphTask *,FDefaultAllocator> & NewTasks, ENamedThreads::Type CurrentThread) Line 295 C++
UE4Editor-Core-Win64-Debug.dll!FTaskThread::ProcessTasks(int QueueIndex, bool bAllowStall) Line 325 C++
UE4Editor-Core-Win64-Debug.dll!FTaskThread::ProcessTasksUntilQuit(int QueueIndex) Line 173 C++
UE4Editor-Core-Win64-Debug.dll!FTaskThread::Run() Line 456 C++
UE4Editor-Core-Win64-Debug.dll!FRunnableThreadWin::Run() Line 64 C++
UE4Editor-Core-Win64-Debug.dll!FRunnableThreadWin::GuardedRun() Line 46 C++
UE4Editor-Core-Win64-Debug.dll!FRunnableThreadWin::_ThreadProc(void * pThis) Line 99 C++
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