Capabilities of the build machine leak into the manpage

[raboof]

Describe the bug

On nix 2.17.1, the nix3-help-stores manpage contains:

       •  system-features

          Optional  features  that  the  system this store builds on implements
          (like “kvm”).

          Default: benchmark big-parallel kvm nixos-test uid-range

However, the Default: line shows the features the system that produced the manpage implements, which might not be same as the features the system this store builds on implements.

This is not only slightly confusing, but means this output is not reproducible, impacting for example the reproducibility of the minimal installation ISO.

This also affects the doc output

Steps To Reproduce

nix-build '<nixpkgs>' -A nix.man --check on a machine that supports different features than Hydra.

Expected behavior

--check succeeds

Priorities

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[raboof]

Could someone with write access to the repo add this issue to the 'Reproducible Builds' GitHub project, with state 'Minimal ISO runtime'?

[cole-h]

Could someone with write access to the repo add this issue to the 'Reproducible Builds' GitHub project, with state 'Minimal ISO runtime'?

Done! (FWIW: this only required triage, not write)

[nixos-discourse]

This issue has been mentioned on NixOS Discourse. There might be relevant details there:

https://discourse.nixos.org/t/nixos-reproducible-builds-minimal-installation-iso-successfully-independently-rebuilt/34756/1