[CrashReport] UE4Editor-MetalShaderFormat.dylib!FGenerateMetalVisitor::print_constant()

UE - Graphics Features - Sep 22, 2017

This is an early trending crash coming out of the 4.18 previews. It occurs on Mac, and all affected project names indicate it is related to AR. Users have not provided any descriptions of their ac ...

Null FPhysicsActorHandle dereference in FBodyInstance::InitDynamicProperties_AssumesLocked when CreateShapes_AssumesLocked fails during async body init

UE - Runtime - Simulation - Aug 2, 2026

Summary When CreateShapes_AssumesLocked fails during async body creation, the failed FBodyInstance is left in Bodies[] with a released actor handle. InitDynamicProperties_AssumesLocked is then called ...

[CrashReport] Crash CheckForWorldGCLeaks() - EditorDestroyWorld()

UE - AI - Sep 8, 2017

This is a somewhat common but longstanding Mac crash that has affected users since at least 4.13. Recently in 4.17.1, the crashes are all occurring in various ARKit projects User DescriptionsI add ...

[CRASH]SIGSEGV: invalid attempt to access memory at address 0x0

Tools - Jan 7, 2015

Callstack: <CALLSTACK START> FTaskThread::ProcessTasksUntilQuit(int) Address = 0x1091943e5 (filename not found) [in UE4Editor-Core.dylib] RenderingThreadMain(FEvent*) Address = 0x10de37e4b (filena ...

Constant Crashes on OS X 10.10.1

UE - Platform - Apple - Dec 15, 2014

User (Omri) on Mac running OS X 10.10.1. on MacBook Pro (17-inch, Early 2009 Experiencing Crash. Cannot reproduce. Crash Reporter: N/A Callstack: MachineId:1E07B9CE2F4554A7C3F421A9DD97AFB5 EpicAc ...

StateTree: While editing State Parameters or exposed properties of a Condition/Task, an ensure() fires when editing inputs of a Property Function bound to an array element

UE - AI - StateTree - Mar 5, 2026

Consider an array property that can be edited in the StateTree editor. This can be a State Parameter or an exposed property of a Condition or Task, for example. Each element of the array can be boun ...

Crash when a StateTree-related Parameter is of a type that includes two nested arrays with the same name (due to FPropertyChangedEvent::ArrayIndicesPerObject using array names to map to their changed indices)

UE - Framework - Dec 19, 2025

This issue was reported in the context of adding and setting parameters on StateTrees, Tasks and related assets, but its root cause lies in the structure FPropertyChangedEvent and can possibly affec ...

Physics simulation shows strange behavior with specific skeletal mesh configurations

UE - Simulation - Physics - Mar 3, 2017

PhAT is inconsistent on when it does and doesn't apply scale to Constraint positions. This leads to cases where the positions provided create constraints that may not work when the Preview Skeletal ...

USplineComponent::GetDistanceAlongSplineAtSplineInputKey returns incorrect result when input keys are not sequential

UE - Editor - May 18, 2022

USplineComponent::GetDistanceAlongSplineAtInputKey() returns the wrong value when the input keys are not sequential because it interprets the input key argument as the spline point index. Thus if th ...