flake: switch to nightly rust with mozilla overlay

flake.lock

@@ -1,5 +1,21 @@
 {
   "nodes": {
+    "mozilla-overlay": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1627922300,
+        "narHash": "sha256-/5fyO/265Wrli2pHpe1/i9Lu8XnQ5K+2YLz9Sz568cI=",
+        "owner": "mozilla",
+        "repo": "nixpkgs-mozilla",
+        "rev": "b1001ed670666ca4ce1c1b064481f88694315c1d",
+        "type": "github"
+      },
+      "original": {
+        "owner": "mozilla",
+        "repo": "nixpkgs-mozilla",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1628696776,
@@ -18,6 +34,7 @@
     },
     "root": {
       "inputs": {
+        "mozilla-overlay": "mozilla-overlay",
         "nixpkgs": "nixpkgs",
         "src-pythonparser": "src-pythonparser",
         "src-sipyco": "src-sipyco"

flake.nix

@@ -2,44 +2,65 @@
   description = "A leading-edge control system for quantum information experiments";
 
   inputs.nixpkgs.url = github:NixOS/nixpkgs/nixos-21.05;
+  inputs.mozilla-overlay = { url = github:mozilla/nixpkgs-mozilla; flake = false; };
   inputs.src-sipyco = { url = github:m-labs/sipyco; flake = false; };
   inputs.src-pythonparser = { url = github:m-labs/pythonparser; flake = false; };
 
-  outputs = { self, nixpkgs, src-sipyco, src-pythonparser }: with import nixpkgs { system = "x86_64-linux"; }; rec {
+  outputs = { self, nixpkgs, mozilla-overlay, src-sipyco, src-pythonparser }:
+    let
+      pkgs = import nixpkgs { system = "x86_64-linux"; overlays = [ (import mozilla-overlay) ]; };
+      rustManifest = pkgs.fetchurl {
+        url = "https://static.rust-lang.org/dist/2021-01-29/channel-rust-nightly.toml";
+        sha256 = "sha256-EZKgw89AH4vxaJpUHmIMzMW/80wAFQlfcxRoBD9nz0c=";
+      };
+      targets = [];
+      rustChannelOfTargets = _channel: _date: targets:
+        (pkgs.lib.rustLib.fromManifestFile rustManifest {
+          inherit (pkgs) stdenv lib fetchurl patchelf;
+        }).rust.override {
+          inherit targets;
+          extensions = ["rust-src"];
+        };
+      rust = rustChannelOfTargets "nightly" null targets;
+      rustPlatform = pkgs.recurseIntoAttrs (pkgs.makeRustPlatform {
+        rustc = rust;
+        cargo = rust;
+      });
+    in rec {
       packages.x86_64-linux = rec {
-      sipyco = python3Packages.buildPythonPackage {
+        sipyco = pkgs.python3Packages.buildPythonPackage {
           name = "sipyco";
           src = src-sipyco;
-        propagatedBuildInputs = with python3Packages; [ pybase64 numpy ];
+          propagatedBuildInputs = with pkgs.python3Packages; [ pybase64 numpy ];
         };
 
-      pythonparser = python3Packages.buildPythonPackage {
+        pythonparser = pkgs.python3Packages.buildPythonPackage {
           name = "pythonparser";
           src = src-pythonparser;
           doCheck = false;
-        propagatedBuildInputs = with python3Packages; [ regex ];
+          propagatedBuildInputs = with pkgs.python3Packages; [ regex ];
         };
 
-      qasync = python3Packages.buildPythonPackage rec {
+        qasync = pkgs.python3Packages.buildPythonPackage rec {
           pname = "qasync";
           version = "0.10.0";
-        src = fetchFromGitHub {
+          src = pkgs.fetchFromGitHub {
             owner = "CabbageDevelopment";
             repo = "qasync";
             rev = "v${version}";
             sha256 = "1zga8s6dr7gk6awmxkh4pf25gbg8n6dv1j4b0by7y0fhi949qakq";
           };
-        propagatedBuildInputs = [ python3Packages.pyqt5 ];
+          propagatedBuildInputs = [ pkgs.python3Packages.pyqt5 ];
-        checkInputs = [ python3Packages.pytest ];
+          checkInputs = [ pkgs.python3Packages.pytest ];
           checkPhase = ''
             pytest -k 'test_qthreadexec.py' # the others cause the test execution to be aborted, I think because of asyncio
           '';
         };
 
-      outputcheck = python3Packages.buildPythonApplication rec {
+        outputcheck = pkgs.python3Packages.buildPythonApplication rec {
           pname = "outputcheck";
           version = "0.4.2";
-        src = fetchFromGitHub {
+          src = pkgs.fetchFromGitHub {
             owner = "stp";
             repo = "OutputCheck";
             rev = "e0f533d3c5af2949349856c711bf4bca50022b48";
@@ -48,14 +69,12 @@
           prePatch = "echo ${version} > RELEASE-VERSION";
         };
 
-      libartiq-support = stdenv.mkDerivation {
+        libartiq-support = pkgs.stdenv.mkDerivation {
           name = "libartiq-support";
           src = self;
-        buildInputs = [ rustc ];
+          buildInputs = [ rustPlatform.rust.rustc ];
           buildPhase = ''
-          # Obviously, #[feature()] can in fact be used on the stable channel, contrary to what the rustc error message says.
+            rustc $src/artiq/test/libartiq_support/lib.rs -Cpanic=unwind -g
-          # You just need to set this obscure RUSTC_BOOTSTRAP environment variable.
-          RUSTC_BOOTSTRAP=1 rustc $src/artiq/test/libartiq_support/lib.rs -Cpanic=unwind -g
           '';
           installPhase = ''
             mkdir $out
@@ -63,17 +82,17 @@
           '';
         };
 
-      artiq = python3Packages.buildPythonPackage rec {
+        artiq = pkgs.python3Packages.buildPythonPackage rec {
           pname = "artiq";
           version = "7.0-dev";
           src = self;
 
           preBuild = "export VERSIONEER_OVERRIDE=${version}";
 
-        nativeBuildInputs = [ qt5.wrapQtAppsHook ];
+          nativeBuildInputs = [ pkgs.qt5.wrapQtAppsHook ];
           # keep llvm_x and lld_x in sync with llvmlite
-        propagatedBuildInputs = [ llvm_9 lld_9 sipyco pythonparser ]
+          propagatedBuildInputs = [ pkgs.llvm_9 pkgs.lld_9 sipyco pythonparser ]
-          ++ (with python3Packages; [ pyqtgraph pygit2 numpy dateutil scipy prettytable pyserial python-Levenshtein h5py pyqt5 qasync llvmlite ]);
+            ++ (with pkgs.python3Packages; [ pyqtgraph pygit2 numpy dateutil scipy prettytable pyserial python-Levenshtein h5py pyqt5 qasync llvmlite ]);
 
           dontWrapQtApps = true;
           postFixup = ''
@@ -86,11 +105,11 @@
           # Allows subprocesses using python to find all packages you have installed
           makeWrapperArgs = [
             ''--run 'if [ ! -z "$NIX_PYTHONPREFIX" ]; then export PATH=$NIX_PYTHONPREFIX/bin:$PATH;fi' ''
-          "--set FONTCONFIG_FILE ${fontconfig.out}/etc/fonts/fonts.conf"
+            "--set FONTCONFIG_FILE ${pkgs.fontconfig.out}/etc/fonts/fonts.conf"
           ];
 
           # FIXME: automatically propagate lld_9 llvm_9 dependencies
-        checkInputs = [ lld_9 llvm_9 outputcheck lit ];
+          checkInputs = [ pkgs.lld_9 pkgs.llvm_9 pkgs.lit outputcheck ];
           checkPhase = ''
             python -m unittest discover -v artiq.test
 
@@ -102,7 +121,7 @@
         };
       };
 
-    defaultPackage.x86_64-linux = python3.withPackages(ps: [ packages.x86_64-linux.artiq ]);
+      defaultPackage.x86_64-linux = pkgs.python3.withPackages(ps: [ packages.x86_64-linux.artiq ]);
     };
 
   nixConfig = {