UE 5.5 Crashes at launch when I activate SM6

General Issues and Bug Reporting
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1

Summary

I’m trying to open my project on UE 5.5 and I need SM6. When I activate it in Plateforms → Windows → D3D12 and restart the editor, the projet crashes when I try to open it, here is the error :

Assertion failed: UniformBuffer [File:D:\build++UE5\Sync\Engine\Source\Runtime\RHI\Private\RHIContex
Attemped to assign a null uniform buffer to the global uniform buffer bindings.
UnrealEditor_RHI
UnrealEditor_Renderer UnrealEditor_Renderer Unrealeditor_Renderer UnrealEditor_RenderCore UnrealEditor_RenderCore UnrealEditor_RenderCore UnrealEditor_RenderCore
UnrealEditor_Core UnrealEditor_Core UnrealEditor_Core UnrealEditor_Core UnrealEditor_Core UnrealEditor_Core UnrealEditor_Core kerne132
ntd11

Please select what you are reporting on:

Creative

What Type of Bug are you experiencing?

Stability

Steps to Reproduce

Activate SM6 in Plateforms → Windows → D3D12 and restart Unreal Engine

Expected Result

The project should open

Observed Result

Crashes right after the first loading when trying to open the project

Platform(s)

Win 10

2

This crash happens on SM6 DX12 if you deactivate Nanite. Check DefaultEngine.ini for r.Nanite.ProjectEnabled=False. Remove this line to avoid crash.

3 Likes
3

That was the solution, it’s working, thanks

4

Anyone else experiencing this who, like me, has Nanite enabled? I’ve checked the DefaultEngine.ini and Nanite is enabled.

This happens pretty predictably using sequencedr/curve editor with fairly basic levels.

Ported my project to a brand new blank project and the issue persists.

Tried loading the project on another PC running an RTX 3090 and the same behavior occurs in the same way.

1 Like
5

Unreal 5.5 crashed with SM6 and Nanite in my project. Sometimes with sequences, sometimes with large objects that cast a lot of small shadows, such as a Willow Tree. Absolutely no problems with this in Unreal 5.4. I usually get an error message that there is probably a shader bug or something similar.

6

Epic hasn’t responded to any of my requests on this thread and others of the same issue - I think the only solve right now is to move back to 5.4 which has worked great so far.

2 Likes
7

We are experiencing the same problem. We also tried with the 5.6 Preview just today, but it is the same. We have a particular map that crashes when SM6 is enabled.
Hope someone can find the solution and post it here. We are now still on 5.4 for this reason.