Scaled Geometry Collections result in a potential memory leak in Physics/ChaosUpdate

UE - Runtime - Simulation - Mar 30, 2025

Scaled Geometry Collections (GC) result in a potential memory leak in Physics. Tracing the memory allocation of a single run of the Editor and multiple Play-In-Editor sessions of a scene that contai ...

[CrashReport] UE4Editor_CoreUObject!HandlePlaceholderScriptRef() [class.cpp:1416]

UE - Gameplay - Blueprint - Nov 10, 2016

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Error message: Access violation - code c0000005 (first/second chance not available) Source C ...

Crash When Changing to Landscape Paint Tool With a Material Function for the World Position Offset of the Landscape Material

UE - Graphics Features - Feb 25, 2019

Crash on switching to landscape/paint tab when using a landscape material that has a material function hooked onto the WorldPositionOffset. Working as expected in 4.21 CL# 4753647 Found in 4.22 CL ...

Invalid array length error launching QAGame onto HTML5

UE - Platform - Mobile - Mar 22, 2017

Firefox 32-bit Version 52.0.1 This error also occurs in MainRangeError: invalid array length[Learn More] 0943e4e3-83fc-4463-accc-9fd15fd7df6c:157:9 processPackageData blob:http://localhost:53501 ...

In 5.6, bWarningsAsErrors does not work with clang

UE - Core - Cpp Tools - UnrealBuildTool - Sep 20, 2025

In 5.6, many warnings and errors specify their command line arguments to the compiler with these new C# attributes:    [WarningsClangToolChain(["-Wno-date-time"], ["-Wdate-time", "-Wno-error=date-ti ...

Instanced Actors: PCG on RuntimeGrid "None" assigns created IAManagers RuntimeGrid "MainGrid", causing cross-grid reference

UE - Graphics Tools - PCG - Graph - May 30, 2026

Context PCG can be used to spawn Instanced Actors via the PCG IA Interop plugin, that makes Spawned Instanced Actors available as node. When a PCGActor placed in the level runs a PCG graph that spa ...

Crash saving a destructible mesh after creating it from static mesh

UE - Simulation - Physics - Destruction - Sep 29, 2016

Crash occurs when saving a destructible mesh after creating it from a static mesh. ...

Editor cannot handle blueprint structure using an Actor Map variable

UE - Gameplay - Blueprint - Aug 28, 2017

If a blueprint structure contains a map variable with Actor Class Reference as the key, populating the map with a custom blueprint (ActorSet) and adding a variable of the structure to any other blue ...

Material expression If node has been broken, major regression that shipped in 4.6

UE - Graphics Features - Dec 9, 2014

This sounds legit. Anyone mess with the if node recently? There seems to be a regression where existing content is broken. This should be fixed ASAP and patched into 4.6. https://forums.unrealen ...

[CrashReport] UE4Editor_Renderer!FBatchingSPDI::DrawMesh() [primitivesceneinfo.cpp:47]

UE - Graphics Features - Jan 3, 2017

Error message: Assertion failed: Mesh.VertexFactory->IsInitialized() [Link Removed] [Line: 45] Source Context: 32 // Keep a reference to the hit proxy from the FPrimitiveSceneInfo, to ensu ...