M1 Native 2021.2.0b33078.7, Shader Keyword Remapping related crashing, both editor and build

Hi, can't provide a repro to file a proper bug report since I haven't yet figured out the definite cause, so I'm in hopes that this is either a known issue or easy to localize.

Both editor and 'iOS on Mac' build crash with a similar-looking stacktrace, seemingly more likely on scene change. It seems to be related to shader keyword remapping. Happens pretty randomly, sometimes together with shader related changes, sometimes just when it feels like it, but it does happen pretty often. I've made a project with the custom shaders I use and I was enacting the same changes I was in the game build but I couldn't cause a crash. I haven't been able to google anything that makes sense in regards to this issue.

I hope someone from the Unity team finds the attached stack traces useful.

I'll try using the same version on Rosetta and see if the issue persists, will update the post.

 

Thanks for the tips. Still happens on b4, I'll be looking harder for a repro as this is a game-breaking bug for me. In the meantime, I could attach the repro attempt as it is right now (no crash) with the custom shaders I'm using. Would that be useful at all?

 

Do they have to contain both UsePass and fallbacks or just either of them? The only shaders with UsePass in the project are the ones from TerrainTools, and I'm not sure they'd even be loaded in playmode/build.

 

Thanks for the info. I've tried removing all the UsePass-having shaders from the project, and also pruning fallbacks from my own shaders, made no difference, still crashing. Could be a third-party one with fallback causing this. Could references to '4Pass' in the stack trace mean that this is a terrain shader?

Also I've submitted a bug report, case #1350950.

 

I would if I knew that lol. Like I said I've tried screwing around with the shaders I have and I haven't been able to repro the crash.

 

If I figure out which shader is causing the issue, I'll post it here. So far I haven't been able to figure that out. I had removed fallbacks from all of my own custom shaders, as well as removing any UsePass ones from the project as a test and it still crashed in the same way.

Update: removed ALL fallbacks and still got the same crash. Probably one of the built-in UI or Terrain Standard shaders then.

 

Noticed another thing - there seem to be a bunch of 'Incompatible keyword states' messages right before the crash. https://forum.unity.com/threads/case-1338318-many-incompatible-keyword-states-errors.1114495/ related?

 

Okay, got another clue - crash doesn't happen when shadows are off (distance set to 0). I then increased the shadow distance and once the shadow distance covered a particular object, the editor crashed. Is this helpful? I'll keep digging.

Edit: Iteration time on this issue would be much faster if not for this issue lol https://forum.unity.com/threads/m1-...setcache-each-time-the-project-loads.1149857/

Edit2: I turned off all the sub-objects of the offending object, and when turning them on one by one, it crashes on random ones inconsistently between each run. Tends to happen more when enabling groups of meshes rather than a particular one. I'll try to recreate this in a repro but I don't feel like it'll work.

Edit3: Yeah I stuck the same model with the same materials and similar lighting, same ProjectSettings, into a new project and I'm not able to get it to crash.

 

I had issues with shader-related exceptions preventing builds after going from 2021.2 alpha to beta. It wasn't crashing the editor but maybe this will help someone with problems like I had. What I did that solved it (..good idea to back up your project before trying), in Project Settings->Graphics, first clear every shader out of "Always Included Shaders". Then hit "Clear" on the "Currently tracked" shaders at the very bottom. Then play your game, go to whatever scenes so your shaders get exposed, toggle any in-game graphics options on/off (like shadows for example). Then before you exit play mode, click the "Save to asset" button. Then add the Shader Variant Collection you've just saved to "Preloaded shaders". After doing this, everything worked again without exceptions. Also note, you can click the Shader Variant Collection asset, then in the Inspector you can add and remove whatever if you want to (vs. going through the entire process again just for a small change).

 

Hi, just got a crash with b8 and indeed it's now pointing at a shader at least:

No keyword remapping data found. Source shader Legacy Shaders/Diffuse, destination shader Legacy Shaders/VertexLit.

Attaching a bigger chunk of the log around it and the stack trace just in case.

 

That's on line 68 of the 'editor log for shader crash' file. I'll post or DM you a full log once the crash happens again, didn't save the full one from this crash unfortunately.

 

Hi, thanks for the fix and the update. I haven't been able to play around on b12-b13 too much due to the domain reloading issue (Unity 2021.2.b12+13: Script domain reload does not work). Quite annoying to have to force a script recompile each time I want to enter play mode. But the ~10 or so times I did so, I enabled shadows and it didn't crash out so that's good. Once the domain reloading issue is fixed (fingers crossed for b14) I'll test this out properly.

 

@aleksandrk

Hi.

It seems that this issue is still happening.
ShaderVariantCollection.WarmUp causes the crash when using a shader contains "UsePass".

I tried report a bug (Case 1425801) in Unity 2021.2.19 with URP 12.1.6, and it also happened in Unity 2021.3.1.

Here is a editor log when a crash occurs.

Code (CSharp):

1.  
2. No keyword remapping data found. Source shader Test/Unlit, destination shader Universal Render Pipeline/Unlit.
3. UnityEngine.StackTraceUtility:ExtractStackTrace ()
4. SVCWarmUpper:Start () (at Assets/SVCWarmUpper.cs:12)
5.  
6. [Assets/SVCWarmUpper.cs line 12]
7.  
8.  
9. =================================================================
10.     Native Crash Reporting
11. =================================================================
12. Got a UNKNOWN while executing native code. This usually indicates
13. a fatal error in the mono runtime or one of the native libraries
14. used by your application.
15. =================================================================
16.  
17. =================================================================
18.     Managed Stacktrace:
19. =================================================================
20.       at <unknown> <0xffffffff>
21.       at UnityEngine.ShaderVariantCollection:WarmUp <0x00140>
22.       at SVCWarmUpper:Start <0x0008a>
23.       at System.Object:runtime_invoke_void__this__ <0x00187>
24. =================================================================
25. Received signal SIGSEGV
26. Obtained 34 stack frames
27. 0x00007ff640c10cb1 (Unity) ShaderLab::Program::GetMatchingSubProgram
28. 0x00007ff640c174ec (Unity) ShaderLab::ShaderState::FindSubProgramsToUse
29. 0x00007ff640c16086 (Unity) ShaderLab::ShaderState::ApplyShaderState
30. 0x00007ff640c083d7 (Unity) ShaderLab::Pass::ApplyPass
31. 0x00007ff640bf0dbe (Unity) DrawVBOChunkWithPass
32. 0x00007ff640bfab5b (Unity) ShaderVariantCollection::WarmupOneShaderImpl
33. 0x00007ff640bfb3da (Unity) ShaderVariantCollection::WarmupShadersImpl
34. 0x00007ff640bfae68 (Unity) ShaderVariantCollection::WarmupShaders
35. 0x00007ff6400df356 (Unity) ShaderVariantCollection_CUSTOM_WarmUp
36. 0x000002de6fa4b551 (Mono JIT Code) (wrapper managed-to-native) UnityEngine.ShaderVariantCollection:WarmUp (UnityEngine.ShaderVariantCollection)
37. 0x000002de6fa4b3ab (Mono JIT Code) [SVCWarmUpper.cs:12] SVCWarmUpper:Start ()
38. 0x000002ddf96f84c8 (Mono JIT Code) (wrapper runtime-invoke) object:runtime_invoke_void__this__ (object,intptr,intptr,intptr)
39. 0x00007ffac2ace0a4 (mono-2.0-bdwgc) [mini-runtime.c:3445] mono_jit_runtime_invoke
40. 0x00007ffac2a0e744 (mono-2.0-bdwgc) [object.c:3066] do_runtime_invoke
41. 0x00007ffac2a0e8dc (mono-2.0-bdwgc) [object.c:3113] mono_runtime_invoke
42. 0x00007ff640e1f454 (Unity) scripting_method_invoke
43. 0x00007ff640e1a074 (Unity) ScriptingInvocation::Invoke
44. 0x00007ff640dee5d2 (Unity) MonoBehaviour::InvokeMethodOrCoroutineChecked
45. 0x00007ff640dee708 (Unity) MonoBehaviour::InvokeMethodOrCoroutineChecked
46. 0x00007ff640de8d32 (Unity) MonoBehaviour::DelayedStartCall
47. 0x00007ff6408e9d04 (Unity) DelayedCallManager::Update
48. 0x00007ff640af8d89 (Unity) `InitPlayerLoopCallbacks'::`2'::EarlyUpdateScriptRunDelayedStartupFrameRegistrator::Forward
49. 0x00007ff640ae06bc (Unity) ExecutePlayerLoop
50. 0x00007ff640ae0793 (Unity) ExecutePlayerLoop
51. 0x00007ff640ae63d9 (Unity) PlayerLoop
52. 0x00007ff641a27ac8 (Unity) PlayerLoopController::UpdateScene
53. 0x00007ff641a137e4 (Unity) PlayerLoopController::EnterPlayMode
54. 0x00007ff641a22b37 (Unity) PlayerLoopController::SetIsPlaying
55. 0x00007ff641a25f3d (Unity) Application::TickTimer
56. 0x00007ff641e6e10a (Unity) MainMessageLoop
57. 0x00007ff641e729db (Unity) WinMain
58. 0x00007ff64319427e (Unity) __scrt_common_main_seh
59. 0x00007ffb57817034 (KERNEL32) BaseThreadInitThunk
60. 0x00007ffb58442651 (ntdll) RtlUserThreadStart
61.  

Regards.

 

@aleksandrk

Oh, I had overlooked it.
I hope that changes will be merged soon.
Thanks!