Bug 237658 – [GODOT] Internal error compiling shader with Metal backend.

• Component: WebGL
• Status: RESOLVED CONFIGURATION CHANGED

[Florian RICHER]

Created attachment 454240 [details]
Full Console log

When i try start private godot game, it crash during loading.

See attachment for more information.

[Radar WebKit Bug Importer]

<rdar://problem/90106648>

[Kimmo Kinnunen]

Thanks for the report. Could you comment on which device and OS version you see this.
Thanks!

[Florian RICHER]

I try only on intel macbook with mac os x 11 and 12.

[Jais Steuer]

Have the same issue with a website aka game Tanki online at: https://tankionline.com/play (safari) it loads but then says there is an error with the backend.
-
iPhone SE 2020 App: Safari. Date: 04/04/22 time 14:19 UTC-7. JAIS STEUER.

[Kimmo Kinnunen]

Florian, would you have a link to content that would reproduce the issue?
The link https://scopema.dev.unova.fr gives me 502 Bad Gateway

[Florian RICHER]

Try this link https://configurateur.scopema.com/ .
It's the production link and not dev link

[Florian RICHER]

This error is generate when godot try Link shader to program here https://github.com/godotengine/godot/blob/3.4/drivers/gles3/shader_gles3.cpp#L449

[Kimmo Kinnunen]

Thanks for the link.
It would be useful if you can figure out the shader that the engine is trying to link.
If you are able to generate a simple project that uses that shader and attach that, it would be even more useful.

[Florian RICHER]

You can see the shader in Full Console.log attached to issue.

It Begin by "[Log]    {LINE_NUMBER} |"

[Florian RICHER]

Created attachment 460606 [details]
Cleaned shader from web console

It's the cleaned shader from "Full Console.log" attachment.

It can contain error because we clean log with a python script

[Florian RICHER]

Created attachment 460615 [details]
Minimal project to reproduce error

I send you minimal project created with Godot.

Attachment contain 2 folders:
  - godot_project : Project created with this version of Godot https://github.com/godotengine/godot/releases/download/3.4.4-stable/Godot_v3.4.4-stable_mono_osx.universal.zip
  - exported_html : Debug export of project

To export manually project from Godot:

  - Unzip file where you want
  - Install Godot from url in above
  - Open godot
  - Click in "Import" button in the right panel
  - Click in "Browse" button
  - Select file PATH/godot_project/project.godot
  - Click in "Open" button
  - Click in "Import and Edit" button
  - When project is open, click in "Project" menu item
  - Click in "Export" button, "HTML5 (Executable)", "Export project" and select the path to export project

If Godot ask you to download "export template", you must download it and re export the project.

[Kyle Piddington]

Was able to reproduce, issue appears to be related to SeperateCompoundExpressions pass.

[Kyle Piddington]

I've been able to write a fix and a test here for this failure:
https://chromium-review.googlesource.com/c/angle/angle/+/3751106/1

The first issue in play is a uniform block being used in a ternary statement, a weird edge case we hadn't considered. 

Unfortunately, even with this fix, we're still seeing issues with Godot due to over-use of local registers. I'm working on a fix at the moment to reduce register pressure.

Once https://chromium-review.googlesource.com/c/angle/angle/+/3751106/1 lands, I expect compilation will pass, but we'll still see runtime or compilation backend failure due to using too many local variables.

[Florian RICHER]

Hi, 

Do you know when you will be able to inform us about a patch will fix the problem ? 
And, for the time being have you a solution to bypass the problem ?
In fact, our platform configurator is completely broken in IOS devices.
Thanks in advance for you reply.

[Florian RICHER]

@Kyle Piddington(In reply to Kyle Piddington from comment #13)
> I've been able to write a fix and a test here for this failure:
> https://chromium-review.googlesource.com/c/angle/angle/+/3751106/1
> 
> The first issue in play is a uniform block being used in a ternary
> statement, a weird edge case we hadn't considered. 
> 
> Unfortunately, even with this fix, we're still seeing issues with Godot due
> to over-use of local registers. I'm working on a fix at the moment to reduce
> register pressure.
> 
> Once https://chromium-review.googlesource.com/c/angle/angle/+/3751106/1
> lands, I expect compilation will pass, but we'll still see runtime or
> compilation backend failure due to using too many local variables.

Pull request is merged but in ios it continue to crash

[Kyle Piddington]

Hello!

I'm no longer seeing this reproduce and am able to use your configurator on iOS 16.4.1.(https://support.apple.com/en-us/HT213407).

If you're still seeing issues after updating, can you tell us more about your configuration, OS version, and specific issues?

Thanks!

[Kimmo Kinnunen]

Should be fixed now in shipping iOS versions