Fix shader compilation failure in Chrome 131

[yakunouyang]

Related

• Mentioned in Error with webviewer #8377

What

rerun/crates/viewer/re_renderer/shader/point_cloud.wgsl

Line 134 in af3312a

let distance = distance(circle_center, world_position);

The variable distance collide with internal function distance(), resulting in wgsl build error on macOS Chrome.

More information in #8377.

[github-actions]

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[emilk]

Thanks!

[Wumpf]

does not fix the linked issue, that was originally about something else entirely
(Fixed description so it doesn't auto-close)

[Wumpf]

Fix can't hurt, but fwiw I can't repro this on MacOs M1 Chrome 133.0.6943.142 which is surprising since this is almost the exact setup you mentioned in #8377 (comment)
Need to check whether Chrome/Tint or Wgpu/Naga is in spec violation here.

[yakunouyang]

Fix can't hurt, but fwiw I can't repro this on MacOs M1 Chrome 133.0.6943.142 which is surprising since this is almost the exact setup you mentioned in #8377 (comment) Need to check whether Chrome/Tint or Wgpu/Naga is in spec violation here.

After some digging, I understand what happened: when I tried to add flag --enable-dawn-features=dump_shaders,disable_symbol_renaming to the chrome browser, it auto updates and take me to the 133.0.6943.142 version. I found the version before update (131.0.6778.0), and this bug reproduces, sorry for the confusion.

As for the specs, this issue may help gpuweb/gpuweb#2619, the latest Chrome/Tint accepts such syntax, and the tint ir dumped by latest Chrome also fixes this problem:

That being said, I think this bug still relevant, it affects the older browsers, and the original symbol seems not accepted by Metal Shader Language.

[Wumpf]

Ah no worries! Then this is the same thing I posted on Discord recently. I didn't break it down via --enable-dawn-features=dump_shaders as you did - didn't know about this, this sounds super useful :)
Agreed, we should land this nonwithstanding, but that does then answer the question whether Chrome or Naga/wgpu are at fault: older Chrome version are, and it's fixed already. But it also means that it's not super urgent.
Thank you so much for following up!

Will take care of the intermittent CI breakage later - seems to be an issue in the non-maintainer ci subset only.