Crash when opening Open World map in editor with -d3d11 -d3ddebug

UE - Graphics Features - Jan 10, 2023

It seems to output an error message like the following. D3D11 ERROR: ID3D11DeviceContext::Dispatch: The Shader Resource View in slot 2 of the Compute Shader unit was not created with the D3D11_BUFF ...

GAS: Crash on resizing FActiveGameplayEffectsContainer::AttributeValueChangeDelegates while executing a contained delegate

UE - Gameplay - Gameplay Ability System - Aug 16, 2024

Game code can register listeners to when a GAS attribute changes value, for example by calling: AbilitySystemComponent->GetGameplayAttributeValueChangeDelegate(SomeAttribute).AddLambda(); These de ...

Integer overflow in NaniteBuilder can lead to an editor crash on certain meshes

UE - Graphics Features - Nanite - Jul 10, 2024

NaniteBuilder uses an int8 type for ExternalEdges and counts adjacency with a int32. The bug stems for the cast to int8 when adding the adjacency count into the ExternalEdges array. The precision l ...

Replicated subobjects list crashes with unreachable yet valid objects when UE_NET_SUBOBJECTLIST_WEAKPTR=0

UE - Networking - May 8, 2023

This seems to occur when the subobject is considered unreachable but is not yet pending kill/marked as garbage. In this case, IsValid returns true while FWeakObjectPtr::Get returns nullptr for the o ...

UE5.4 Regression - crash when disabling shader optimization while raytracing is enabled on D3D12

UE - Rendering Architecture - Shaders - Jul 15, 2024

Certain interactions between a Rect Light with a Light Function and a Post-Process volume lead to a check() when compiling a Ray Tracing PSO for tracing lights. This check() only happens when shader ...

UClass::SparseClassDataStruct null at editor-time for child blueprints until compile

UE - Framework - Blueprint - May 29, 2024

Child blueprints of a blueprint of a native actor class with sparse data can have an incorrectly null SparseClassDataStruct value, and thus fail to initialzie their SparseClassData. This affects edi ...

GeometryCollectionActor SetSimulatePhysics false does not stop Physics Simulation

UE - Simulation - Physics - Nov 28, 2024

If the GeometryCollectionActor (GCA) is simulating physics, calling SetSimulatePhysics(false) does not stop the simulation. If the simulation is paused, calling SetSimulatePhysics(true) does as expe ...

ConditionalBeginDestroy on ActorComponent does not unregister the component with the world nor cause a warning

UE - CoreTech - May 6, 2025

Calling ConditionalBeginDestroy on an ActorComponent (instead of DestroyComponent) can lead to a crash due to the object not being correctly unregistered. BeginDestroy doesn't unregister tick funct ...