Unreal Engine Issues
Unreal Engine Issues
BuildPatchTool crashes on Mac and Linux when building android or ios with multiple chunks
Portal - Feb 18, 2020"It seems that deallocation of TLazySingleton<FInternationalization> causes unhandled exception. If DISABLE_LAZY_SINGLETON_DESTRUCTION=1 is provided - the build completes successfully" ...
"Build All Levels" does not re-AddNavigationSystemToWorld
UE - AI - Navigation - Feb 28, 2024The Build All Levels editor action cleans up the world's NavDataSet (UNavigationSystemV1::NavDataSet) as pre-rebuild world cleanup by calling: SetNavigationSystem(nullptr); inside UWorld::Cleanu ...
Exception on missing file during GC in horde storage
UE - Foundation - Horde - Storage - May 7, 2025During GC, if a file was manually deleted (but the storage system is still track), GC can erroneously fail (and never remove the reference). This causes a backup in GC, putting the whole algorithm i ...
Alt-tabbing out of a Standalone App or packaged version of a game does not trigger LostFocus or ReceiveFocus
Tools - Sep 9, 2015If a user uses Alt-tab to change to another window, the ReceivedFocus and LostFocus functions are not called as they would usually be called when using something such as Shift+F1 or Ctrl+Esc. Note: ...
FIXIF: Using the Merge Blueprints feature crashes the editor
UE - Gameplay - Blueprint - Feb 18, 2015Using the Merge Blueprints feature crashes the editor. This repro is for clicking between the error and warnings while merging, but the editor will generally crash if the Merge is finished or if an ...
[CrashReport] Mac crash - libobjc.A.dylib!objc_retain() [UnknownFile]
UE - Platform - Apple - Nov 10, 2017This is a longstanding but low frequency Mac crash. User DescriptionsChanging camera shake values and testing in a new editor window Callstack from Log[2017.11.09-19.23.22:392][ 63]LogMaterial: Mi ...
Blueprints not marked dirty when variables in referenced actors are renamed
UE - Gameplay - Blueprint Compiler - Feb 20, 2018Blueprints using renamed variable do not indicate that they need to be recompiled. (However errors are shown on play) It is possible to not see an error if you add a variable with the same name as ...
Niagara Scalability Crash When Processing Significance
UE - Niagara - Jun 4, 2025Method FNiagaraScalabilityManager::ProcessSignificance() iterates on indices from Context.SignificanceIndices and uses them to access the State and ManagedComponents arrays. It can then decide to cr ...
Editor crashes when changing skeletal mesh if another skeletal mesh component is attached when using master pose node
OLD - Anim - Jan 27, 2020The crash only occurs if the additional skeletal mesh component is used with Set Master Pose Component (see ToggleAttach function in the TopDownCharacter BP). It doesn't seem to matter what mesh we' ...
Set user focus for player 0 will cause other local players to lose input
UE - Gameplay - Input - Feb 28, 2019When the player at index 0 sets its user focus it will cause other players to lose input. This does not occur when setting the user focus of players with an index higher than 0. ...