Please fix libcpuid for aarch64

frozen · May 4, 2026, 1:36am

Hello all! I am a novice NixOS arm64 user here, please fix libcpuid to add aarch64, it has stopped my nixos-rebuild switch from working for several days now. This is all because I installed the ‘picard’ package and now the only way I can install anything is to constantly type export NIXPKGS_ALLOW_UNSUPPORTED_SYSTEM=1

Please fix this! Thank you kindly! There’s no reason for it not to work, it compiles just fine manually, and I’ve tried reporting it on Matrix already

Cheers !!

MaxHearnden · May 4, 2026, 1:42am

The picard package doesn’t appear to depend on libcpuid on arm64. Could you share your configuration.nix so that we can see if anything else depends on libcpuid?

You could also try running nixos-rebuild with the --show-trace argument to show the full stack trace.

magicquark · May 4, 2026, 2:14am

This has been fixed in this PR:

github.com/NixOS/nixpkgs

libcpuid: enable building on ARM

master ← K900:libcpuid-arm

opened 04:46AM - 01 May 26 UTC

K900

+2 -2

Upstream supports both aarch32 and aarch64, only tested on aa64. ## Thi…ngs done - Built on platform: - [x] x86_64-linux - [x] aarch64-linux - [ ] x86_64-darwin - [ ] aarch64-darwin - Tested, as applicable: - [ ] [NixOS tests] in [nixos/tests]. - [ ] [Package tests] at `passthru.tests`. - [ ] Tests in [lib/tests] or [pkgs/test] for functions and "core" functionality. - [ ] Ran `nixpkgs-review` on this PR. See [nixpkgs-review usage]. - [x] Tested basic functionality of all binary files, usually in `./result/bin/`. - Nixpkgs Release Notes - [ ] Package update: when the change is major or breaking. - NixOS Release Notes - [ ] Module addition: when adding a new NixOS module. - [ ] Module update: when the change is significant. - [x] Fits [CONTRIBUTING.md], [pkgs/README.md], [maintainers/README.md] and other READMEs. [NixOS tests]: https://nixos.org/manual/nixos/unstable/index.html#sec-nixos-tests [Package tests]: https://github.com/NixOS/nixpkgs/blob/master/pkgs/README.md#package-tests [nixpkgs-review usage]: https://github.com/Mic92/nixpkgs-review#usage [CONTRIBUTING.md]: https://github.com/NixOS/nixpkgs/blob/master/CONTRIBUTING.md [lib/tests]: https://github.com/NixOS/nixpkgs/blob/master/lib/tests [maintainers/README.md]: https://github.com/NixOS/nixpkgs/blob/master/maintainers/README.md [nixos/tests]: https://github.com/NixOS/nixpkgs/blob/master/nixos/tests [pkgs/README.md]: https://github.com/NixOS/nixpkgs/blob/master/pkgs/README.md [pkgs/test]: https://github.com/NixOS/nixpkgs/blob/master/pkgs/test

Tracking:

frozen · May 4, 2026, 2:19am

Shoot I think it’s ‘freac’ then (freac.org) , the encoder which I use with picard every day

frozen · May 4, 2026, 2:23am

How do I apply the fix? It’s becoming a major nuisance

Thank you all!

magicquark · May 4, 2026, 2:29am

You would need to overlay the libcpuidpackage with the changes made in the PR. But this is more trouble than it is worth imo.

If you wait, the channel should update soon.

To avoid having to set the environment variable manually, you can set allowUnsupportedSystem = true; in your configuration.

waffle8946 · May 4, 2026, 3:31am

Wait a couple days, it’s almost reached nixos-unstable.