Setting a struct bool property (bitfield) to itself writes the wrong value

UE - Framework - Blueprint Compiler - Sep 17, 2025

There's an issue when assigning a bitfield bool to a native bool in Blueprints. Currently, the engine erroneously treats the memory for a local bool as a uint8 bitfield, which is undefined behavior. ...

[CrashReport] UE4Editor_Engine!FPointerToUberGraphFrame::~FPointerToUberGraphFrame()

UE - Gameplay - Blueprint - Aug 15, 2017

This is a trending crash coming out of the 4.17.0 release. Users have not provided any descriptions of their actions when the crash occurred, however the callstack is very similar to [Link Removed] ...

[CrashReport] UE4Editor_Landscape!FLandscapeComponentSceneProxy::FLandscapeComponentSceneProxy() [landscaperender.cpp:680]

UE - LD & Modeling - Terrain - Landscape - Apr 11, 2018

User comment in crash group:Wanted to delete a single field of my landscape wich is very big. Same error appears if I try to get a part of the landscape to another streaming level. Would be cool if ...

CheckCompilingPSOs assert in FMaterialPSORequestManager::MarkCompilationComplete fires occasionally

Find the root cause and fix it. Potential issue based on logs:New RequestA is created in PrecachePSOs and its collection task is dispatched and finishedRequestA is waiting for compilation taskReque ...

Compile error in ShadowDepthVertexShader.usf if INTERPOLATE_POSITION

UE - Graphics Features - Oct 21, 2015

Shader compile error in function PositionOnlyMain() in ShadowDepthVertexShader.usf if defined INTERPOLATE_POSITION. LogShaderCompilers:Warning: 1 Shader compiler errors compiling WorldGridMaterial ...

Undo/Redo can cause the gizmo to desync from a leaf-selected component

UE - Editor - Workflow Systems - Oct 18, 2021

This is a regression from 4.27. This is happening because of the change to typed elements. UEditorEngine::PostUndo, when combined with the typed element changes causes the selection set to reorder ...

AbilityTask_PlayMontage will 'zombie' if Interrupted during BlendOut

UE - Gameplay - Gameplay Ability System - Apr 14, 2023

User reports: I've noticed a bug with PlayMontageAndWait There are 4 possible triggers when a Montage completes:OnCompletedOnBlendOutOnInterruptedOnCancelled Once OnBlendout has been triggere ...

Niagara module inputs don't handle bitfield enums correctly

UE - Niagara - Feb 17, 2025

As one clicks on the enum fields trying to form an input, the log is written with a variation of the following: [2025.02.14-17.42.38:940][521]LogNiagaraEditor: Error: Error getting default value fo ...

Orphaned BP actors when using UWorldPartitionBuilder

UE - World Creation - Worldbuilding Tools - World Partition - Nov 21, 2025

From an EPS case: --------------------------------- We're seeing a recurring issue where child BP actors are becoming orphaned during any processing that uses UWorldPartitionBuilder. It affects ...

Using a Wait Delay node on Linux causes editor to immediately close without crashing

UE - Platform - Linux - Sep 14, 2015

If a call is made to the blueprint node Wait Delay the editor will immediately close during PIE when the call is made without the crash reporter appearing. The "Wait Delay" node only exists on Linu ...