Build with several targets installed?

[Nadrieril]

Hi! Thanks for this very convenient and reliable project!

I'm writing a rustc driver that analyses rust code. In my test suite, some of the tests pass --target i686-unknown-linux-gnu (or other targets) to my binary. Today this fails in crane because only the host target is available.

I know that crane can cross-compile if I give it the right target on the nix side, but that's not what I need: I want my crate to be compiled for the host as usual, yet have a few extra target toolchains available. Is that possible with crane?

[RossSmyth]

If you want more toolchains available, you need to use https://github.com/oxalica/rust-overlay
as there is no (sane) way to install more toolchains just with nixpkgs unfortunately. So for Charon I see you have this in your flake. You'd do something like:

        rustToolchain = (pkgs.rust-bin.fromRustupToolchainFile ./rust-toolchain).override {
            targets = [ "i686-unknown-linux-gnu" ];
        };
        craneLib = (crane.mkLib pkgs).overrideToolchain (p: p.rust-bin.stable.latest.default);
        ocamlformat = pkgs.ocamlPackages.ocamlformat_0_27_0;

This will have some additional toolchain(s) available to rustc.

[dpc]

fenix works too, BTW.