Nix: Mark clash-ffi broken on the GHC version it does not work on

Co-authored-by: Rowan Goemans <[email protected]>

Author: DigitalBrains1

.github/workflows/nix.yml

@@ -80,6 +80,10 @@ jobs:
             "clash-term",
             "clash-testsuite"
         ]
+        exclude:
+          - ghc: ghc984
+            package: clash-ffi
+
     needs: packages_common
     steps:
       - uses: actions/checkout@v4

nix/overlay-ghc98.nix

@@ -1,7 +1,7 @@
 { pkgs }:
 final: prev:
 let
-  inherit (pkgs.haskell.lib) doJailbreak markUnbroken;
+  inherit (pkgs.haskell.lib) doJailbreak markUnbroken overrideCabal;
 in
 {
   # Use an older version than the default in nixpkgs. Since rewrite-inspector
@@ -21,4 +21,9 @@ in
 
   # singletons-th 3.3 requires th-desugar 1.16
   th-desugar = prev.callHackage "th-desugar" "1.16" { };
+
+  # Broken on GHC 9.8.4 see clash-ffi cabal file for details
+  clash-ffi = overrideCabal prev.clash-ffi (drv: {
+    broken = true;
+  });
 }

nix/overlay.nix

@@ -90,6 +90,7 @@ let
           ];
         });
 
+      # Broken on GHC 9.8.4
       clash-ffi =
         prev.haskell.lib.overrideCabal (hprev.callCabal2nix "clash-ffi" ../clash-ffi {})
           (drv: {
@@ -225,9 +226,9 @@ let
 
   haskellOverlays =
     prev.lib.composeManyExtensions [
-      ghcOverlay
       haskellExternalPackages
       haskellInternalPackages
+      ghcOverlay
     ];
 in
 {