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overlays/ghc-packages.nix

@@ -70,7 +70,11 @@ let
       template-haskell = "libraries/template-haskell";
       iserv        = "utils/iserv";
     } // final.lib.optionalAttrs (builtins.compareVersions ghcVersion "9.4" < 0) {
+      # The version of `Win32` that comes with ghc 9.4 (2.12.0.0) is older
+      # than the one in hackage.  Including it causes `cabal configure` to fail.
       Win32        = "libraries/Win32";
+      # As of GHC 9.4 this has been split out of the GHC repo and
+      # is now in the iserv-proxy flake input
       iserv-proxy  = "utils/iserv-proxy";
     } // final.lib.optionalAttrs (!final.stdenv.hostPlatform.isGhcjs || builtins.compareVersions ghcVersion "8.10.5" >= 0) {
       # Not sure why, but this is missing from older ghcjs versions