python312Packages.pytorch: just disable -Werror; fix darwin x64 build

[paparodeo]

pytorch and many of the vendored libs build with -Werror and the derivation meticulously then disables any warning that results in a build failure. Just disable -Werror and fix the x64 darwin build.

https://hydra.nixos.org/build/282440946

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/)
• 25.05 Release Notes (or backporting 24.11 and 25.05 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (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.

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[paparodeo]

@ofborg build python312Packages.pytorch

[GaetanLepage]

That's a more radical solution, but it's fine by me.
I'll let @SomeoneSerge have the final word on this.

[SomeoneSerge]

Agreed, I can hardly see how -Werror is useful at deployment time. It would make more sense in a devShell`