Unreal Engine Issues
Unreal Engine Issues
Editor FPS has significant drop when moving a BSP brush in level with multiple BSPs
UE - AI - Navigation - Jan 8, 2025Editor performance plummets when moving BSP brushes in a level with several other BSP brushes present. Navmesh regeneration is the main cause as the full bounds for all BSP are used to determine whi ...
Creating a code project named Test will fail the initial compile and every hot reload in Binary
UE - Foundation - Build - Farm - Jul 21, 2016When a C++ project is named Test on a Binary version of the editor, the project will fail to compile. I'm assuming this is from the editor seeing a precompiled header from another file in the engine ...
FBasePassMeshProcessor crashes in ODSC code because the WorldGridMaterial doesn't support translucency
UE - Rendering Architecture - Jan 30, 2023UDN: [Link Removed] Slack: [Link Removed] Then, the return value of TryAddMeshBatch is determined by FBasePassMeshProcessor::Process. When the crash occurs, GetBasePassShaders fails to get the shad ...
Crash when using StaticDuplicateObject with mismathced Source and Destination class types
UE - Foundation - Jun 19, 2025Starting in Unreal Engine 5.4, StaticDuplicateObject internally switched to using Unversioned Property Serialization (UPS) for performance reasons. However, UPS assumes the source and destination ob ...
Actor Component properties can become "linked" across multiple Blueprints after a hot reload
UE - Gameplay - Components - Dec 3, 2018If code in an Actor Component class is changed (eg. a new UPROPERTY is added) and a hot reload is performed to implement the changes, the properties in the component can become linked across any Blu ...
GAS: AbilitySystemComponent does not DestroyActiveState after re-entering play
UE - Gameplay - Gameplay Ability System - Oct 30, 2023UAbilitySystemComponent::DestroyActiveState() is called when the component is unregistered (OnUnregister) and when its destroyed (OnComponentDestroyed). It performs state cleanup such as canceling a ...
Crashes after destroying a skeletal mesh attached via socket name (not bone name), the destroyed mesh remains welded.
UE - Simulation - Physics - Jul 18, 2025On welding physics bodies during primitive component attachment, UPrimitiveComponent::WeldToImplementation() calls GetRootWelded() and then GetBodyInstance() on the returned root. This searches by b ...
[CrashReport] Assertion failed: !PinRef->bWasTrashed | UEdGraphPin::SerializePin()
UE - Gameplay - Blueprint - Aug 29, 2017This is a common and longstanding crash that has occurred since at least 4.15 and affected nearly 500 users. The CrashGroup was previously linked to [Link Removed], but that had specific repro step ...
When a BPActor containing HISMs is multiplied with a scale, LOD display control doesn't work correctly
UE - Rendering Architecture - Nov 29, 2023Workaround 1: 1. Change HierarchicalInstancedStaticMesh.cpp in either of the following ways:void{{ FHierarchicalStaticMeshSceneProxy::GetDynamicMeshElements(const TArray<const FSceneView*>& Views, c ...
Out-of-bounds read caused by improper return size from FSocketSteam::RecvFrom in Unreal Engine
UE - Online - Jun 7, 2021Overview: Function at fault: FSocketSteam::RecvFrom (https://github.com/EpicGames/UnrealEngine/blob/c3caf7b6bf12ae4c8e09b606f10a09776b4d1f38/Engine/Plugins/Online/OnlineSubsystemSteam/Source/Private/ ...