haskell.packages.ghc902Binary: fix evaluation of package set (#496292)

pkgs/development/haskell-modules/configuration-ghc-9.0.x.nix

@@ -37,4 +37,21 @@ self: super: {
   unix = null;
   xhtml = null;
   Win32 = null;
+
+  # core pkgs on later GHCs that we can reasonably provide a stub
+  # or Hackage released version for (though they may not build).
+  Cabal-syntax = self.Cabal-syntax_3_6_0_0;
+  semaphore-compat = self.semaphore-compat_2_0_0;
+  os-string = self.os-string_2_0_10;
+  file-io = self.file-io_0_2_0;
+  # Would need 2.25.*, but let's not bother
+  haddock-api = self.haddock-api_2_29_1;
+  haddock-library = self.haddock-library_1_11_0;
+
+  # core pkgs on later GHCs we can't provide at all
+  system-cxx-std-lib = null;
+  ghc-experimental = null;
+  ghc-internal = null;
+  ghc-platform = null;
+  ghc-toolchain = null;
 }

pkgs/development/haskell-modules/configuration-hackage2nix/main.yaml

@@ -78,6 +78,7 @@ extra-packages:
   - Cabal == 3.14.*
   - Cabal == 3.16.*                     # version required for cabal-install and other packages
   - cabal-add == 0.1                    # 2025-09-09: Only needed for hls 2.11 can be removed once we are past it.
+  - Cabal-syntax == 3.6.*               # required for the GHC 9.0.2 package set
   - Cabal-syntax == 3.10.*
   - Cabal-syntax == 3.12.*
   - Cabal-syntax == 3.14.*

pkgs/development/haskell-modules/hackage-packages.nix

@@ -6122,6 +6122,20 @@ self: {
     }
   ) { };
 
+  Cabal-syntax_3_6_0_0 = callPackage (
+    { mkDerivation, Cabal }:
+    mkDerivation {
+      pname = "Cabal-syntax";
+      version = "3.6.0.0";
+      sha256 = "0lcj4g55sj5iv727g7k57pscgyj0fx3smwapm1gmd5qkc3yfa9fa";
+      libraryHaskellDepends = [ Cabal ];
+      doHaddock = false;
+      description = "A library for working with .cabal files";
+      license = lib.licenses.bsd3;
+      hydraPlatforms = lib.platforms.none;
+    }
+  ) { };
+
   Cabal-syntax_3_10_3_0 = callPackage (
     {
       mkDerivation,