Nixpkgs stdenv.mkDerivation fixed point's doCheck is incorrect when cross compiling

flake.lock

{
  "nodes": {
    "flake-utils": {
      "inputs": {
        "systems": "systems"
      },
      "locked": {
        "lastModified": 1709126324,
        "narHash": "sha256-q6EQdSeUZOG26WelxqkmR7kArjgWCdw5sfJVHPH/7j8=",
        "owner": "numtide",
        "repo": "flake-utils",
        "rev": "d465f4819400de7c8d874d50b982301f28a84605",
        "type": "github"
      },
      "original": {
        "id": "flake-utils",
        "type": "indirect"
      }
    },
    "nixpkgs": {
      "locked": {
        "lastModified": 1710116904,
        "narHash": "sha256-3DS+98ECHRTinAHRyiORa1TPEmQ5qgbsZfnUfflWwZI=",
        "owner": "NixOS",
        "repo": "nixpkgs",
        "rev": "6ae71359c4ddd67dcea3edd4bc7b1c437aa1e7f3",
        "type": "github"
      },
      "original": {
        "owner": "NixOS",
        "ref": "master",
        "repo": "nixpkgs",
        "type": "github"
      }
    },
    "root": {
      "inputs": {
        "flake-utils": "flake-utils",
        "nixpkgs": "nixpkgs"
      }
    },
    "systems": {
      "locked": {
        "lastModified": 1681028828,
        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
        "owner": "nix-systems",
        "repo": "default",
        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
        "type": "github"
      },
      "original": {
        "owner": "nix-systems",
        "repo": "default",
        "type": "github"
      }
    }
  },
  "root": "root",
  "version": 7
}

flake.nix

{
  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/master";
    flake-utils.url = "flake-utils";
  };

  outputs = { self, nixpkgs, flake-utils }:
    flake-utils.lib.eachDefaultSystem (system: let

      pkgs = import nixpkgs {
        localSystem = { inherit system; };
        crossSystem = {
          system = "armv7l-linux";
        };
      };

      inherit (pkgs) lib;

      pkgFn = {
        lib,
        stdenv,
        writeShellScript,
      }: stdenv.mkDerivation (finalAttrs: {
        name = "mkderivation-fixedpoint-lies";

        doCheck = true;

        phases = [ "installPhase" ];

        installPhase = ''
          # Outputs `declare -x doCheck=""`, indicating that doCheck is set to an
          # empty string, the string-coerced version of `false`.
          declare -p doCheck | tee -a $out
          # Outputs `finalAttrs.doCheck: true`.
          echo "finalAttrs.doCheck: ${lib.boolToString finalAttrs.doCheck}" | tee -a $out
        '';
      });

      package = pkgs.callPackage pkgFn { };

    in {
      packages.default = builtins.trace
        # outputs `trace: package.doCheck fromoutside: false`
        "package.doCheck from outside: ${lib.boolToString package.doCheck}"
        package;
    })
  ;
}