Is it possible for naersk to use stable Rust

[wezm]

Hi apologies for my naïvety. I'm very new to Nix.

All the instructions I have found so far describe using nightly rust with naersk. I would rather use a release version of stable rust. Is this possible?

I tried removing "-Z" "unstable-options" from cargoOptions but it seems that was there to allow the use of --out-dir. Can the CARGO_TARGET_DIR be used instead?

[nmattia]

Hi! Unless you've tweaked the settings, rust stable is used. Those are cargo options, they won't impact the actual compiler. Does that help?

[wezm]

No sorry, I don't think that's right. Those options only work on nighly versions of cargo:

$ cargo --version
cargo 1.42.0 (86334295e 2020-01-31)

$ cargo -Z unstable-options build
error: the `-Z` flag is only accepted on the nightly channel of Cargo, but this is the `stable` channel
See https://doc.rust-lang.org/book/appendix-07-nightly-rust.html for more information about Rust release channels.

$ cargo build --out-dir foo
error: the `--out-dir` flag is unstable, and only available on the nightly channel of Cargo, but this is the `stable` channel
See https://doc.rust-lang.org/book/appendix-07-nightly-rust.html for more information about Rust release channels.
See https://github.com/rust-lang/cargo/issues/6790 for more information about the `--out-dir` flag.

[lblasc]

I hit the same problem when I tried to use stable rust from mozilla-overlay.

  pkgs = import sources.nixpkgs {
    overlays = [
      nixpkgs-mozilla
      (self: super:
          rec {
            rust = (self.rustChannelOf { date = "2020-05-07"; channel = "stable"; }).rust;
            rustc = rust;
            cargo = rust;
            rls = rust;
          }
      )
    ];
  };

[ralsei]

Thirding this. Tried:

{ sources ? import ./nix/sources.nix
, pkgs ? import sources.nixpkgs {} }:
let
  rust = import ./nix/rust.nix { inherit sources; };

  naersk = pkgs.callPackage sources.naersk {
    rustc = rust;
    cargo = rust;
  };

  # tell nix-build to ignore the "target" directory
  src = builtins.filterSource
    (path: type: type != "directory" || builtins.baseNameOf path != "target")
    ./.;
in naersk.buildPackage {
  inherit src;
  cargoOptions = v: [];
  cargoBuildOptions = v: [ "$cargo_release" ''-j "$NIX_BUILD_CORES"''
                           "--message-format=$cargo_message_format"];
  cargoBuild = v: ''
    OUT_DIR=out cargo $cargo_options build $cargo_build_options >> $cargo_build_output_json
  '';
  remapPathPrefix = true; # remove nix store refs
}

(where ./nix/rust.nix is stable rust from nixpkgs-mozilla), and got this far:

    Finished release [optimized] target(s) in 47.03s
/nix/store/qghrkvk86f9llfkcr1bxsypqbw1a4qmw-stdenv-linux/setup: eval: line 1329: syntax error near unexpected token `||'
builder for '/nix/store/zrh0165cdhjg715xz3i2xi5r6s0l4fkm-lake-deps-0.2.0.drv' failed with exit code 2
cannot build derivation '/nix/store/8qa3543617i9jm159gp6s5ak9fr5983r-lake-0.2.0.drv': 1 dependencies couldn't be built
error: build of '/nix/store/8qa3543617i9jm159gp6s5ak9fr5983r-lake-0.2.0.drv' failed

There's got to be better ways to do this. As it currently stands, naersk is unusable with stable Cargo.

[jbaum98]

I also have this issue. I think that the --out-dir flag is unstable according to this, and according to the README that flag is important.

[jbaum98]

Okay, I figured out a trick: you can override rust to use a version with the mozilla overlay, and leave cargo untouched. Alternatively, I imagine you can override cargo to use a nightly version of cargo in a similar fashion, I haven't tried that yet.

let rustOverlay = self: super:
  let rust = (super.rustChannelOf {
    channel = "1.44.0";
    sha256 = "cc2f6f7515b934457bc537ed181aa04e9a844fa8567f6dae7b9403d1a5a7a09e";
  }).rust; in { rustc = rust; };

[klardotsh]

Is there any movement on this as far as mainlining some form of stable support? Taking a hard dependency on nightly is something I'd like to avoid in production. (I also can't seem to get @jbaum98's solution working in my project, which uses niv, but I'll keep playing with it)

[nmattia]

@klardotsh as mentioned above, I believe this only requires cargo nightly, not rustc nightly. Is this acceptable for you? If there's a big enough need for it I can try to figure out how to do this with cargo stable, please 👍 if you're interested

[paulyoung]

I'm using flakes and haven't been able to figure out how to use a stable version of the rust toolchain from nixpkgs but use a compatible nightly build version of cargo yet.

I'll post here if I get something that works.

[veehaitch]

If there's a big enough need for it I can try to figure out how to do this with cargo stable

I also ran into this when switching from nightly to stable. I would appreciate it if I could use the very same version of the rust toolchain during development and packaging, regardless of the rust channel.

[evanjs]

If there's a big enough need for it I can try to figure out how to do this with cargo stable

I also ran into this when switching from nightly to stable. I would appreciate it if I could use the very same version of the rust toolchain during development and packaging, regardless of the rust channel.

I was also thinking about this.
I am now referencing oxalica via tarball url to ensure rustc is always the latest stable, but deferring cargo's version to naersk.

I am curious if relying on the latest stable rustc and a potentially older nightly for cargo might cause any issues.

[dpc]

Seems like a simple thing to fix so I gave it a try and now I have a PR. So far it works for me.

[wezm]

Oh wow, thanks @dpc. If the fix is this simple, I'm embarrassed I didn't come up with it in my efforts before opening the issue last year.

[dpc]

Maybe it isn't, and I just don't know about it yet. 🤷 :)

[nmattia]

Ok, looks like there's a pretty big demand for this! @jonringer is it something you feel like tackling?

[jonringer]

Yea, I can try.

Just a little busy in my personal life for the short term.

[dpc]

Please reopen, because the PR was reverted. We are not giving up yet. :D

[tv42]

It seems naersk stopped using unstable cargo option --out-dir in commit 08afb3d (setting CARGO_TARGET_DIR instead). There are still some remnants of it in docs and comments, but it seems naersk works with stable cargo now.

[Patryk27]

Seems like --out-dir is not used anymore, so I'm gonna go ahead and close this issue; if something's not working as intended, please feel free to re-open 🙂