Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key causes a memory leak

UE - Framework - Blueprint - Apr 15, 2025

When Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key, the function construct the default structure in-place on the given pointer without destroying the object. This behavior ca ...

macOS build appears to hang due to UBT deadlocking on ps buffer

UE - Foundation - Cpp Tools - Apr 22, 2021

Licensee reports buffer deadlock issue in System/BuildHostPlatform.cs (lines 283-329). Moving Proc.WaitForExit() to after the for-loop seems to resolve the issue for them.publicoverride ProcessInf ...

[CrashReport] UE4Editor_CoreUObject!FWeakObjectPtr::operator=() [weakobjectptr.cpp:28]

UE - Anim - Sequencer - Nov 3, 2016

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Error message: Access violation - code c0000005 (first/second chance not available) Source C ...

[CrashReport] UE4Editor_Engine!ULevel::GetWorldSettings() [level.cpp:1781]

Tools - Aug 22, 2016

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below. Error message: Assertion failed: WorldSettings != ...

In BP/Python Editor Utilities, function SetEditorProperty() unexpectedly fails for Actor Reference Properties on External Actors.

UE - World Creation - Worldbuilding Tools - May 19, 2024

As part of the Python and Editor Scripting Tools, it is possible to programmatically set variables in actor instances of the current level just like when using the Details Panel in the Level Editor. ...

SCS child scene component instances can be registered out-of-order with non-scene component instances (regression).

UE - Gameplay - Components - Sep 7, 2016

This behavior is a regression in 4.12. Essentially we switched to attaching child components as part of the OnRegister() logic. This caused all root-level SCS components (including non-scene compone ...

[CrashReporter]UnrealEditor-Engine!UWorldPartition::GenerateStreaming(TArray<FString,TSizedDefaultAllocator<32> > *) [WorldPartitionStreamingGeneration.cpp:570]

UE - World Creation - Worldbuilding Tools - World Partition - May 31, 2022

Generated from CrashReporter user's comment: Everytime I press "Play" in this specific project, the program crashes ...

"Save Current As" is not fully loading the newly-saved level

Tools - Mar 15, 2017

Workaround: Navigate to and open the newly-created level in the Content Browser prior to LaunchOn. After using the Save Current As tool, Game runs into error when trying to LaunchOn. Editor display ...

[AI] BehaviorTreeEditor crash when swapping from Behavior Tree to Blackboard view.

UE - AI - BehaviorTree - Aug 24, 2023

The first time that a Behavior Tree editor window changes from the tree to the Blackboard can cause a crash if you add and remove a key from the Blackboard via a different Behavior Tree editor windo ...

Editor Crashes when copy/pasting an emitter in the Niagara timeline

UE - Niagara - Feb 8, 2023

When creating the emitter's track widget we search for the stack view model's root entry, but the stack view model pointer is null, so we crash.  ...