FPackedRGBA16N is divide by 32768 twice in NEON/FPU

UE - Platform - Mobile - May 6, 2022

Reimporting an asset during PIE overwrites the bAllowCPUAccess value to true

UE - Editor - Content Pipeline - Import and Export - May 22, 2025

When reimporting a static mesh asset before PIE execution, the value of bAllowCPUAccess is false.  If reimporting a static mesh asset while PIE is running, the value of bAllowCPUAccess is true. In a ...

Struct with a single unaltered element will remove the element from the struct on compile

UE - Gameplay - Blueprint - Oct 7, 2015

If used inside a UMG Blueprint, a struct that has only one element will remove the element from the struct after compiling the blueprint. If the element is edited or a second element is added then ...

[CrashReport] Linux crash - TOpenGLBuffer<FOpenGLBaseVertexBuffer, 34962u, &()

UE - Platform - Linux - Sep 14, 2017

This is an infrequent Linux crash that has affected a few users in 4.17.1 Callstack from Log[2017.09.12-17.23.41:651][ 0]LogRHI: OpenGL MajorVersion = 4, MinorVersion = 5, ShaderPlatform = GLSL_43 ...

Map placed actor binding to another actor's Event Dispatcher (multicast delegate) results in duplicate bindings after blueprint recompile

UE - Framework - Blueprint - Apr 17, 2025

Context Blueprint actors placed on the map can bind to another actor's event. If an ActorB has a reference to ActorA, it can bind to an event dispatcher in A by creating an event node in ActorB's e ...

ARSharedWorld, AREnvProbe, and ARSaveLoad fail to build for iOS with clang error

UE - Platform - Mobile - Jul 18, 2019

ARSharedWorld fails to package at the build command for iOS with the following messages. Packaging (iOS): [1/4] sh /Volumes/Storage/Workspaces/Release/Samples/AR/ARSharedWorld4.23/Binaries/IOS/ARS ...

~FStaticMesh() can crash with race condition

UE - Graphics Features - Mar 21, 2017

UDN user reported frequent crashes in FStaticMesh::~FStaticMesh() on DrawListLinks[i]->Remove(false); Crash went away after adding critical sections to FStaticMesh::LinkDrawList(), FStaticMesh::Unl ...

[CrashReport] Assertion on Mac in FCocoaRunLoopSource

UE - Platform - Apple - Jun 14, 2017

This is a common crash among Mac users in 4.16. It is spread out among many separate CrashGroups, with slight variations in Callstack. Some Example CrashGroups [Link Removed] [Link Removed] [Link ...

App on Gear VR crashes when trying to join a listen server as a client

UE - Platform - XR - Dec 10, 2015

If the user tries to join a listen server with an app that is running on the Gear VR the App will stop working. ...

Compile error during build stage when packaging for tvOS

UE - Platform - Mobile - Dec 9, 2016

Compile error packaging for tvOS: Does not affect iOSUATHelper: Packaging (tvOS): UnrealBuildTool: D:\Build\joseph.wysosky_Main\Engine\Source\Runtime\Core\Private\iOS\IOSAppDelegate.cpp(388,12): ...