Unreal Engine Issues
Unreal Engine Issues
iOS/tvOS fails to build from source editor built with Xcode 9.3, macro expansion producing 'defined' has undefined behavior
UE - Platform - Mobile - Apr 2, 2018Trying to launch on or package for TVOS or iOS from a source build of Mac or Windows will fail with errors:[2018.04.02-16.35.08:522][634]LogPlayLevel: In file included from /Volumes/Storage/GitHub ...
"Go to Definition" does not work properly in Binary
UE - Foundation - Core - Feb 1, 2018Using the Go to definition option on a blueprint node in the Binary editor opens Visual Studio but does not actually show the definition as requested. The user is instead given the following warning ...
FixDeps runs on every build even without any changes
UE - Platform - Linux - Oct 21, 2016This has been fixed for 4.15, but 4.14 was branched before the fix. Note that this issue is distinct from [Link Removed] and the fix is much simpler. Note that [Link Removed] (pull request #2839) ...
Resave commandlet broken when using BuildEnvironment = TargetBuildEnvironment.Unique;
UE - CoreTech - May 14, 2024The explanation from the licensee seems pretty comprehensive. Text from the UDN: We've been trying to run fixupredirects via the resavepackages commandlet, but noticed that the OFPA assets were no ...
When moving actors to the current level, their label is reset and displayed incorrectly on the Scene Outliner until the next time it is refreshed
UE - Editor - Workflow Systems - Jul 14, 2025This is a regression, it worked correctly up to UE 5.4, but repros on UE 5.5 and 5.6. Also, this seems related to [Link Removed], which was fixed by CL 40649716/40649749 and integrated into UE 5.6, ...
Geometry Collection (GC) fragments are affecting the Navmesh in wrong positions
UE - Simulation - Physics - Destruction - Dec 6, 2024Geometry Collection (GC) fragments are affecting the Navmesh in wrong positions and the identified cause is wrong indexing. Once a GC breaks, it's fragments, when big enough, are creating islands in ...
When used with First Loop Start Frame Offset and Use Animation Blueprint, the character will alternate between the specified animation and the reference pose
UE - Anim - Anim in Engine - Jan 30, 2023If you use StartFrameOffset set to 1 or higher in conjunction with the Use Animation Blueprint, the character's animation will be rough towards the end of the section. Specifically, it seems that th ...
Paper2D performance regression due to TArray resizing
UE - Graphics Features - Aug 16, 2019We've noticed after upgrading our heavy Paper2D project to 4.22 that tilemap performance has been massively degraded compared to previous versions. After some digging we found out that it's due to a ...
FViewElementPDI::DrawLine calls for SDPG_World are not rendered in PIE or in Game
UE - Rendering Architecture - RHI - Jan 7, 2026When View.Family->EngineShowFlags.CompositeEditorPrimitives is false in the function RenderEditorPrimitivesForDPG. This code picks which version of the batched lines to renderconst FBatchedElements ...
Crash on map change with non-null values for GPropertyColorationClass and request customizable property coloration color
UE - Editor - Workflow Systems - Aug 7, 2023This was found by a customer through a UDN, and they offered the fix for it, as well. The basic steps to reproduce the crash are as follows:call GEditor->SetPropertyColorationTarget(...) somewhere i ...