shader-slang: 2025.8.1 -> 2025.12.1

[samestep]

Upgrades shader-slang from 2025.8.1 to 2025.12.1

This PR fixes up #416790 by applying the updated patch mentioned in #424144, and then "resolves" the reference cycle error by having the derivation be single-output; this was the only fix I could figure out at the moment with my limited Nix expertise. I don't have a good understanding of what the drawbacks are.

Changelogs:

• https://github.com/shader-slang/slang/releases/tag/v2025.12.1
• https://github.com/shader-slang/slang/releases/tag/v2025.12
• https://github.com/shader-slang/slang/releases/tag/v2025.11.1
• https://github.com/shader-slang/slang/releases/tag/v2025.11
• https://github.com/shader-slang/slang/releases/tag/v2025.10.5
• https://github.com/shader-slang/slang/releases/tag/v2025.10.4
• https://github.com/shader-slang/slang/releases/tag/v2025.10.3
• https://github.com/shader-slang/slang/releases/tag/v2025.10.2
• https://github.com/shader-slang/slang/releases/tag/v2025.10.1
• https://github.com/shader-slang/slang/releases/tag/v2025.10
• https://github.com/shader-slang/slang/releases/tag/v2025.9.2
• https://github.com/shader-slang/slang/releases/tag/v2025.9.1
• https://github.com/shader-slang/slang/releases/tag/v2025.9

cc @niklaskorz

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandboxing enabled in nix.conf? (See Nix manual)
  • sandbox = relaxed
  • sandbox = true
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• Nixpkgs 25.11 Release Notes (or backporting 25.05 Nixpkgs Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
• NixOS 25.11 Release Notes (or backporting 25.05 NixOS Release notes)
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
• Fits CONTRIBUTING.md, pkgs/README.md, maintainers/README.md and other contributing documentation in corresponding paths.

---

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[niklaskorz]

Thank you a lot for fixing the patches! I'll have a look into the circular reference issue, as I'd prefer keeping the separate outputs :)

[niklaskorz]

The cyclic dependency was caused by cmake/ being contained in $out, which referenced headers in $dev, while $dev references $out as propagated build input.

The solution was moving cmake/ to $dev, as the cmake definitions are only ever needed as development input.

[niklaskorz]

nixpkgs-review result

Generated using nixpkgs-review.

Command: nixpkgs-review pr 424153
Commit: a073be5064d11fd8a86136c564603c96b284d2e7

---

x86_64-linux

✅ 4 packages built:

• shader-slang
• shader-slang.debug
• shader-slang.dev
• shader-slang.doc

[niklaskorz]

nixpkgs-review result

Generated using nixpkgs-review.

Command: nixpkgs-review pr 424153
Commit: a073be5064d11fd8a86136c564603c96b284d2e7

---

aarch64-darwin

✅ 3 packages built:

• shader-slang
• shader-slang.dev
• shader-slang.doc

[samestep]

Thanks @niklaskorz for fixing and merging this!

As a heads up, this package will need to be manually fixed again for the next Slang release, due to shader-slang/slang#7577 (the build still succeeds on the previous commit shader-slang/slang@00746bf).

I'm wondering whether it would make sense to try to upstream any of this into the Slang repo; also cc @expipiplus1 who maintains her own Slang flake.nix but has limited bandwidth at the moment.

[niklaskorz]

Thanks @niklaskorz for fixing and merging this!

As a heads up, this package will need to be manually fixed again for the next Slang release, due to shader-slang/slang#7577 (the build still succeeds on the previous commit shader-slang/slang@00746bf).

I'm wondering whether it would make sense to try to upstream any of this into the Slang repo; also cc @expipiplus1 who maintains her own Slang flake.nix but has limited bandwidth at the moment.

Yeah we should definitely upstream these patches, they are breaking too often to maintain them in nixpkgs I'm afraid.

[samestep]

@niklaskorz the Slang repo currently has a flake.nix which just holds a devShell; would you have any interest in opening a PR adding a defaultPackage for nix build by using (some of?) the setup/patches already in Nixpkgs? Or what do you think may be the best way to go about this?