Cook non-determinism when serializing UObject pointers pointing to garbage

UE - CoreTech - UObject - Aug 25, 2025

There's a cook determinism issue in the way UObject unversioned serialization handles UObject pointers pointing to garbage. Depending on GC timing, it can either be skipped (as a property matching C ...

Inconsistent Behavior of TFieldPath and nullptr comparison

UE - CoreTech - UObject - Mar 7, 2025

Commit 6448c6f (https://github.com/EpicGames/UnrealEngine/commit/6448c6f6d1de1e9fac9614248e06ba06b837814d) introduced inconsistent behavior for TFieldPath and nullptr comparison, depending on constn ...

FDateRange cannot be declared as UPROPERTY

UE - CoreTech - UObject - Sep 4, 2024

Unlike other range wrapper structs, such as FFloatRange, marking a FDateRange as a UPROPERTY results in the following error: error : Unable to find 'class', 'delegate', 'enum', or 'struct' with nam ...

Disabling Disregard for GC with an invalid asset in GameplayTagTableList causes a controlled crash

UE - CoreTech - UObject - Jul 31, 2024

Disabling Disregard for GC leads to a crash in GarbageCollectionVerification.cpp VerifyObjectFlags. This crash occurs when there is an invalid path specified in GameplayTagTableList. The cause of t ...

Make ConfigBranch creation thread safe

UE - CoreTech - UObject - Jun 28, 2024

See [Link Removed] for details ...

Renaming assets hits an ensure related to circular redirect

UE - CoreTech - UObject - May 10, 2024

You will hit the ensure condition: LogOutputDevice: Error: Ensure condition failed: !SeenPaths.Contains(CurrentPath) in Engine\Source\Runtime\CoreUObject\Private\Misc\RedirectCollector.cpp] [Line ...

Incorrect Redirector(s) created when renaming a LevelSequence

UE - CoreTech - UObject - Jan 19, 2024

Renaming the LevelSequence also renames the internal DirectorBP. Renaming the BP triggers the rename of its BlueprintGeneratedClass asset. A Redirector will be created for the BGC but it will be in ...

GameThread + AsyncLoadingThread deadlock - StaticLoadObject vs. StaticAllocateObject

UE - CoreTech - UObject - Feb 14, 2023

User reported encountering a deadlock between GameThread and AsyncLoadingThread and provided two callstacks.User quote I've been running into a deadlock intermittently with a custom blueprint conso ...

Crash occurs when renaming an asset that is used by Class Default Object

UE - CoreTech - UObject - Nov 23, 2021

Not a regression. Tested in: //UE4/Release-4.26.2 CL15973114 Binary - Reproduced //UE4/Release-4.27.1 CL17735300 Binary - Reproduced //UE5/Release-5.0-EarlyAccess CL16682836 Binary - Reproduced Fro ...

JSON Serializer FromJson function returns true when property types don't match

UE - CoreTech - UObject - Nov 16, 2021

If the type of a property in a Json string doesn't match the expected type in the Json serializable class being created, then the value for that property will not be read in. However, FromJson still ...