Bump to GHC 9.6.4, update tools (#900)

 - Update to GHC 9.6.4

This release includes [this GHC
commit](https://gitlab.haskell.org/ghc/ghc/-/commit/1ae57288cabdd818180f38c9f55d8da8ac4c1d0c),
potentially fixing #164.
- Update [HLS
2.6](https://github.com/haskell/haskell-language-server/releases/tag/2.6.0.0),
which in particular includes the following improvement:

> Improvements to multiple home unit support with GHC 9.4. Using cabal
3.11+ will
load proper multiple home unit sessions by default, fixing a lot of
issues with
loading and reloading projects that have more than one component.

   Also bump cabal HEAD as motivated by this.
 - Remove now-redundant haskell.nix workaround for mingwW64.
 - Bump stylish-haskell to 0.14.6.0 and cabal-fmt to 0.1.10.

.github/workflows/ci.yml

@@ -20,7 +20,7 @@ jobs:
     strategy:
        fail-fast: false
        matrix:
-         ghc: ["8.10.7", "9.6.3"]
+         ghc: ["8.10.7", "9.6.4"]
          cabal: ["3.10.1.0"]
          os: [ubuntu-latest]
     env:
@@ -172,7 +172,7 @@ jobs:
       if: |
         github.event_name == 'push'
         && github.ref == 'refs/heads/main'
-        && matrix.ghc=='9.6.3'
+        && matrix.ghc=='9.6.4'
       run: |
         cabal build --dry-run --enable-tests all
         ./scripts/docs/haddocks.sh
@@ -182,7 +182,7 @@ jobs:
       if: |
         github.event_name == 'push'
         && github.ref == 'refs/heads/main'
-        && matrix.ghc=='9.6.3'
+        && matrix.ghc=='9.6.4'
       uses: actions/upload-artifact@v4
       with:
         name: haddocks

CONTRIBUTING.md

@@ -168,7 +168,7 @@ and improvements are always welcome.
 
 ## Formatting the code
 
-We use `stylish-haskell` 0.14.5.0 for Haskell code formatting.
+We use `stylish-haskell` 0.14.6.0 for Haskell code formatting.
 
 Either enable editor integration or call the script used by CI itself:
 

nix/haskell.nix

@@ -14,7 +14,7 @@ let
   };
   hsPkgs = haskell-nix.cabalProject {
     src = ./..;
-    compiler-nix-name = "ghc963";
+    compiler-nix-name = "ghc964";
     flake.variants = {
       ghc810 = { compiler-nix-name = lib.mkForce "ghc8107"; };
     };
@@ -34,9 +34,6 @@ let
               extraSrcFiles = [ "golden/${n}/**/*" ];
             }) [ "byron" "shelley" "cardano" ]);
       }
-      ({ lib, pkgs, ... }: lib.mkIf pkgs.stdenv.hostPlatform.isWindows {
-        reinstallableLibGhc = false;
-      })
     ];
     flake.variants = {
       noAsserts = {

nix/shell.nix

@@ -22,7 +22,7 @@ hsPkgs.shellFor {
   # This is the place for tools that are required to be built with the same GHC
   # version as used in hsPkgs.
   tools = lib.mapAttrs (_: t: t // { index-state = pkgs.tool-index-state; }) {
-    haskell-language-server = { version = "2.5.0.0"; };
+    haskell-language-server = { version = "2.6.0.0"; };
   };
 
   shellHook = ''

nix/tools.nix

@@ -2,7 +2,7 @@ inputs: final: prev:
 
 let
   inherit (final) lib;
-  tool-index-state = "2024-01-01T00:00:00Z";
+  tool-index-state = "2024-01-22T00:00:00Z";
   tool = name: version: other:
     final.haskell-nix.tool final.hsPkgs.args.compiler-nix-name name ({
       version = version;
@@ -19,8 +19,8 @@ in
     src = final.fetchFromGitHub {
       owner = "haskell";
       repo = "cabal";
-      rev = "27f4ee71d949837ba31e170d205fbe6c1ecf847d";
-      hash = "sha256-Ia0CgKuqtYynSIR1TQd2/enB+IpzCYrB7CbbVBb3Rus=";
+      rev = "adc283a0f06c7d24aeed67e69aca3d71c04010b3";
+      hash = "sha256-3K9WVR/tINK3PyGlXpypSpp1pguHTnolDruHNE+VvE4=";
     };
     index-state = tool-index-state;
     inherit (final.hsPkgs.args) compiler-nix-name;
@@ -48,9 +48,9 @@ in
     '';
   };
 
-  stylish-haskell = tool "stylish-haskell" "0.14.5.0" { };
+  stylish-haskell = tool "stylish-haskell" "0.14.6.0" { };
 
-  cabal-fmt = tool "cabal-fmt" "0.1.9" { };
+  cabal-fmt = tool "cabal-fmt" "0.1.10" { };
 
   haskellBuildUtils = prev.haskellBuildUtils.override {
     inherit (final.hsPkgs.args) compiler-nix-name;