Unreal Engine Issues
Unreal Engine Issues
USkeletalMeshComponent::HandleExistingParallelClothSimulation() calling WaitUntilTaskCompletes can trigger arbitrary task that modifies currently iterated UWorld::ComponentsThatNeedPreEndOfFrameSync
UE - Rendering - Architecture - Feb 23, 2024Context ActorComponents can schedule an end-of-frame update for themselves by calling UWorld::MarkActorComponentForNeededEndOfFrameUpdate. The UWorld will iterate all those actor components once pe ...
Physics Asset primitives are being created with the default Name as None instead of BoneName_PrimitiveType
UE - Editor - Content Pipeline - FBX - Oct 27, 2024When creating Physics Assets, either by automatic creation upon import, creation from skeletal meshes already in the project, or when we press Generate All Bodies (bottom right of a opened Physics A ...
[CrashReport][Crash] Engine!FSceneViewport::UpdateViewportRHI() [SceneViewport.cpp]
UE - Rendering - Architecture - RHI - May 29, 2026#200 crash out of 2101 in UE 5.8 on Windows#34 crash for UE - Rendering - Architecture in UE 5.8 on Windows#20 crash for UE - Rendering - Architecture - RHI in UE 5.8 on WindowsAssertion failed: IsI ...
Editor crashes on blueprint open when shortcut key is implemented through code
UE - Gameplay - Jun 7, 2017Editor crashes on blueprint open when shortcut key is implemented through code inside of the BaseEditorPerProjectUserSettings.ini. Code used in repro is directly from Jeff W suggestion in the forum ...
AutoSize triggers ensure on shortened Skel Anim Section moved past anim length
UE - Anim - Sequencer - May 26, 2026In Sequencer, calling "Edit > Auto Size" on a UMovieSceneSkeletalAnimationSection triggers the LowerBound > UpperBound ensure in UMovieSceneSection::SetRange (MovieSceneSection.h:333) when the secti ...
ARM64 projects crash on device with Signal 11 with GooglePlay plugin enabled
UE - Platform - Mobile - Sep 20, 2016When launching ASTC ARM64 packaged project onto S7, it'll crash with Signal 11. It seems very similar to [Link Removed]. ...
Orientation Warping breaks incoming poses where bones are in component space
UE - Anim - Gameplay - Apr 17, 2025The orientation warping node breaks incoming poses where bones are already in component space. This is because, in EvaluateSkeletalControl_AnyThread, we are repeatedly setting bone transforms direc ...
Changing the ComponentClass of a ACharacter twice and trying to set a SkeletalMeshAsset crashes the engine
UE - Anim - Jan 22, 2026Changing the ComponentClass of a ACharacter twice and trying to set a SkeletalMeshAsset crashes the engine with a "Cannot replace existing object of a different class" message. The conditions to re ...
Assert crash when playing Groom Cache with Card Mesh LOD
UE - Rendering - Graphics Features - May 29, 2026Playing a Guides Groom Cache while Card Mesh LOD (Guide-Based) is active causes an assert in RunHairStrandsInterpolation_Cards when the renderer switches to Card LOD. Assert location:Plugins/Runtim ...
[CrashReport] Access violation - FLandscapeEditDataInterface::SetAlphaData()
UE - LD & Modeling - Terrain - Landscape - Jul 19, 2017This is a common crash affecting users in 4.15 and 4.16. This callstack was previously linked to [Link Removed], but that had a specific repro case that was fixed in 4.14. Users are not providing ...