Crash when a StateTree-related Parameter is of a type that includes two nested arrays with the same name (due to FPropertyChangedEvent::ArrayIndicesPerObject using array names to map to their changed indices)

UE - Framework - Dec 19, 2025

This issue was reported in the context of adding and setting parameters on StateTrees, Tasks and related assets, but its root cause lies in the structure FPropertyChangedEvent and can possibly affec ...

Data Layers: GetDataLayerInstanceFromAssetName differs between editor and non-editor

UE - World Creation - Worldbuilding Tools - Data Layers - Apr 9, 2024

From licensee: The function AWorldDataLayers::GetDataLayerInstanceFromAssetName() uses different names in #WITH_EDITOR and without editor builds: #WITH_EDITOR config calls DataLayerInstance->GetDa ...

[CrashReport][Assert] UnrealEditor-RHI!FRHIResource::MarkForDelete() [Engine/Source/Runtime/RHI/Private/RHIResources.cpp:49]

UE - Rendering - Architecture - Materials - Dec 18, 2024

One of the users described this issue as below. "At seemingly random times while working in the material graph, some action will cause a hitch or freeze, and quickly after the engine will crash, an ...

[CrashReport][Crash] UnrealEditor-Core!IMemoryReadStream::CopyTo()

UE - Rendering - Architecture - Apr 10, 2025

Intermittent crash in virtual texture transcode. Usually mempy from nullptr but also occasionally we see the same callstack with memcpy to random location. ...

Chaos : Crash when destroying part of Geometry collections clustered by AnchorField

UE - Simulation - Physics - May 10, 2021

Here's a workaround void DestroyParticle(TGeometryParticleHandle<T, d>* Particle) { auto PBDRigid = Particle->CastToRigidParticle(); if(PBDRigid) { RemoveFromMapAndArray(PBDRigid, Ac ...

[CrashReport] Linux crash - llvm::TargetLowering::LowerCallTo()

UE - Platform - Linux - Jul 20, 2017

This is a common Linux crash in 4.16.2. ...

A Simulating Physics component with StartAwake = false will be awoken by a Welded component

UE - Simulation - Core - Jan 10, 2025

A Simulating Physics component with StartAwake = false will be awoken by a Welded component If a welding occurs during the call to OnCreatePhysicsState, this breaks the start awake disabled flag. Th ...

Linux crashes in the Project Browser without using the -nocef command

UE - Platform - Linux - Feb 22, 2022

When opening Unreal Editor on Linux, the Project Browser opens but is completely unresponsive. Shortly afterwards the editor will crash. If you use the -nocef command when opening the Editor, everyt ...

New VR-Basic level triggers Metal validation layer assertion

UE - Platform - Apple - Mar 16, 2020

This was discovered externally and reported on UDN here: https://udn.unrealengine.com/questions/563268/mac-editor-crash-when-disable-ambient-occlusion.html ...