UE5 Crashing after modifying physics constraint on object that has had an attached component destroyed

Development Programming & Scripting
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This is quite hard to explain but I will do my best. I am trying to create a trailer type object that the player can attach to with a physics constraint and pull around behind them this is working fine when I interact with the trailer a physics joint updates its attached components and I am able to pull it around.

Part of this trailer blueprint is another blueprint which is a storage blueprint that basically consists of a box collision that monitors overlapping objects and if the object has a particular tag and hasn’t moved from the last tick it attaches that object to it so they move together.

This all seems to work ok some of the time, but most of the time usually after I have stored some items, attached my player to the trailer, moved the trailer about, detached from the trailer, picked up an item (detaching it from the storage and destroying the item) and then when I re-attach to the trailer the editor crashes with the following error:

Assertion failed: (Index >= 0) & (Index < ArrayNum) [File:D:\build++UE5\Sync\Engine\Source\Runtime\Core\Public\Containers\Array.h] [Line: 771] Array index out of bounds: 7 from an array of size 5

UnrealEditor_Chaos
UnrealEditor_Chaos
UnrealEditor_Chaos
UnrealEditor_Chaos
UnrealEditor_Chaos
UnrealEditor_Chaos
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
kernel32
ntdll

I really can’t work out what is causing the problem it seems like chaos is struggling to update the attached components / not clearing the detached components from its internal arrays and thus looking for an index in an array of the wrong size.

2

Greetings @sketchy_b

Welcome back to the Unreal Engine Community Forums. In regards to the error that you’re running into with ‘Array index out of bounds’, I’d recommend taking a peek at this post. This users issue was caused using different plugins and such. But, the array index explanation may be helpful. I hope this helps explain it!