Crash when using CastChecked<>(nullptr, ECastCheckedType::NullAllowed) in configurations where checks are disabled

UE - CoreTech - Jun 19, 2025

When using CastChecked<>(), the second parameter can be passed as ECastCheckedType::NullAllowed to make the check succeed when the input is nullptr. However, in UE 5.5 up to the latest engine versio ...

Loading Duplicated Level via Python API Crashes Editor

UE - Editor - Workflow Systems - Feb 16, 2023

When called from Python, in 5.1 the load level invocation results in a kernel panic style crash of the editor, with a message about the map leaking memory and not being able to be garbage collected ...

Behavior of Speed Up/Down parameter of Auto Exposure are different.

UE - Graphics Features - Apr 5, 2016

Brend/Swtch multi PostProcessVolume to handle Auto Exposure with same Speed Up/Down parameter but behavior of Speed Up/Down parameter of Auto Exposure are different. Scene with. Unbounded PostProce ...

Physics not reacting correctly with physical material if velocity is not high enough

UE - Simulation - Physics - Feb 3, 2015

There are issues with the way Physics is being handled with physical materials. Having a physical material setup with a restitution of 1 and a high max depenetration value will result in no bounce. ...

Occasional 1-frame UMG render data corruption on Metal

UE - Graphics Features - May 10, 2016

Crash Upon Opening Project in 4.7 preview 5

UE - Foundation - Core - Feb 4, 2015

The user claims to have converted his project with each new version of the engine starting from 4.2. Comments left in crash reporter "Tried to open project" Creating bug for tracking purposes unti ...

Localization warnings when opening a new project in 4.8.1

Tools - Jul 2, 2015

There are a couple of warnings that show up in the output log that are dealing with localization when opening up a new project. ...

UE 4.25.1 Offline Installer Display Error

UE - Editor - Content Pipeline - Datasmith - Importer - Jun 9, 2020

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