Nix refactor

.gitignore

@@ -52,3 +52,6 @@ inspect/
 *.rs.fixed
 analysis.txt
 polonius_cache/
+
+# Nix output symlinks
+result*

README.md

@@ -64,7 +64,7 @@ For example, the official LLVM packages from [apt.llvm.org](https://apt.llvm.org
 - **NixOS / nix:**
 
     ```sh
-    nix-shell
+    nix shell github:immunant/c2rust
     ```
 
 - **macOS:** Xcode command-line tools and recent LLVM (we recommend the Homebrew version) are required.

default.nix

@@ -1,22 +1,14 @@
+final: prev:
 let
-  nixpkgs = import <nixpkgs> { };
-  inherit (nixpkgs) pkgs llvmPackages;
-  stdenv = pkgs.clangStdenv;
+  # Get rust-overlay from the flake.lock file
+  rustNodes = (builtins.fromJSON (builtins.readFile ./flake.lock)).nodes.rust-overlay.locked;
+  rust-overlay = final.fetchFromGitHub {
+    inherit (rustNodes) owner repo rev;
+    hash = rustNodes.narHash;
+  };
+
+  overlain = final.extend (import rust-overlay);
 in
-stdenv.mkDerivation {
-  name = "c2rust";
-  buildInputs = [
-    pkgs.clang
-    pkgs.cmake
-    pkgs.llvm
-    pkgs.libllvm
-    pkgs.openssl
-    pkgs.pkgconfig
-    pkgs.python3
-    pkgs.rustup
-    pkgs.zlib
-  ];
-  LIBCLANG_PATH = "${pkgs.libclang.lib}/lib";
-  CMAKE_LLVM_DIR = "${llvmPackages.libllvm.dev}/lib/cmake/llvm";
-  CMAKE_CLANG_DIR = "${llvmPackages.libclang.dev}/lib/cmake/clang";
+{
+  c2rust = overlain.callPackage ./nix { };
 }

flake.nix

@@ -2,75 +2,45 @@
   description = "Flake for c2rust";
 
   inputs = {
-    nixpkgs.url = "github:NixOS/nixpkgs/nixos-23.11";
-    utils.url = "github:numtide/flake-utils";
-    fenix = {
-      url = "github:nix-community/fenix";
-    };
-    oxalica = {
-      url = "github:oxalica/rust-overlay";
-    };
+    nixpkgs.url = "https://nixos.org/channels/nixos-unstable/nixexprs.tar.xz";
+    flake-utils.url = "github:numtide/flake-utils";
+    rust-overlay.url = "github:oxalica/rust-overlay/snapshot/2024-08-01";
+    rust-overlay.inputs.nixpkgs.follows = "nixpkgs";
   };
 
-  outputs = inputs@{ self, nixpkgs, utils, fenix, oxalica}:
-    utils.lib.eachDefaultSystem (system:
-    let
-        fenixStable = fenix.packages.${system}.fromToolchainFile {
-          file = ./rust-toolchain.toml;
-          sha256 = "sha256-r/8YBFuFa4hpwgE3FnME7nQA2Uc1uqj0eCE1NWmI1u0";
-        };
+  outputs =
+    {
+      self,
+      nixpkgs,
+      flake-utils,
+      rust-overlay,
+    }:
+    flake-utils.lib.eachDefaultSystem (
+      system:
+      let
         pkgs = import nixpkgs {
           inherit system;
           overlays = [
-            (import oxalica)
+            (import rust-overlay)
+            (import self)
           ];
-          config = {
-            allowUnfree = true;
-          };
         };
-        in {
-          defaultPackage = self.devShell.${system};
-          devShell = pkgs.mkShell.override { } {
+      in
+      {
+        packages = {
+          default = pkgs.c2rust;
+          unwrapped = pkgs.c2rust.unwrapped;
+        };
+
+        overlays = import self;
 
-            LIBCLANG_PATH = "${pkgs.llvmPackages_14.libclang.lib}/lib";
-            CMAKE_LLVM_DIR = "${pkgs.llvmPackages_14.libllvm.dev}/lib/cmake/llvm";
-            CMAKE_CLANG_DIR = "${pkgs.llvmPackages_14.libclang.dev}/lib/cmake/clang";
-            shellHook = ''
-              export CARGO_TARGET_DIR="$(git rev-parse --show-toplevel)/target_dirs/nix_rustc";
-            '';
-            RUST_SRC_PATH = pkgs.rustPlatform.rustLibSrc;
-            buildInputs =
-              with pkgs; [
-                clangStdenv.cc
-                llvmPackages_14.libclang
-                pkg-config
-                fenix.packages.${system}.rust-analyzer
-                llvmPackages_14.clang
-                cmake
-                llvmPackages_14.llvm
-                llvmPackages_14.libllvm
-                openssl
-                (python3.withPackages
-                  (python-pkgs:
-                    with python-pkgs;
-                    [ "bencode-python3"
-                      cbor
-                      colorlog
-                      mako
-                      pip
-                      plumbum
-                      psutil
-                      pygments
-                      typing
-                      "scan-build"
-                      pyyaml
-                      toml
-                    ]
-                  )
-                )
-                zlib
-                (rust-bin.fromRustupToolchainFile ./rust-toolchain.toml)
-              ];
-          };
-    });
+        devShells.default = pkgs.callPackage ./shell.nix { };
+
+        formatter = pkgs.nixfmt-tree;
+        checks = {
+          inherit (pkgs) c2rust;
+          devShell = self.devShells.${system}.default;
+        };
+      }
+    );
 }

nix/default.nix

@@ -0,0 +1,28 @@
+{
+  lib,
+  runCommand,
+  callPackage,
+  makeBinaryWrapper,
+  llvmPackages,
+}:
+let
+  c2rust = callPackage ./package.nix { };
+in
+runCommand "c2rust-${c2rust.version}"
+  {
+    inherit (c2rust) version meta;
+    nativeBuildInputs = [
+      makeBinaryWrapper
+    ];
+
+    passthru.unwrapped = c2rust;
+  }
+  ''
+    makeWrapper ${lib.getExe c2rust} "$out/bin/c2rust" \
+      --prefix PATH : ${
+        lib.makeBinPath [
+          c2rust.toolchain
+          llvmPackages.libllvm
+        ]
+      }
+  ''