WIP: Preliminary ghc 9.14 support

cabal.project

@@ -14,9 +14,9 @@ repository cardano-haskell-packages
 -- update either of these.
 index-state:
   -- Bump both the following dates if you need newer packages from Hackage
-  , hackage.haskell.org 2025-09-21T21:31:06Z
+  , hackage.haskell.org 2025-10-01T19:08:20Z
   -- Bump this if you need newer packages from CHaP
-  , cardano-haskell-packages 2025-09-18T12:21:32Z
+  , cardano-haskell-packages 2025-10-01T14:54:47Z
 
 packages: cardano-constitution
           plutus-benchmark
@@ -75,16 +75,205 @@ source-repository-package
   tag: e814b9171398cbdfecdc6823067156a7e9fc76a3
 
 allow-newer:
-  -- https://github.com/tweag/HaskellR/pull/420
-  , inline-r:singletons-th
-  , inline-r:aeson
-  , inline-r:text
-  , inline-r:template-haskell
-  , inline-r:deepseq
-  , inline-r:bytestring
-  , inline-r:containers
-  , inline-r:primitive
+  -- https://github.com/phadej/vec/issues/121
+  ral:QuickCheck,
+  fin:QuickCheck,
+  bin:QuickCheck,
 
 -- https://github.com/IntersectMBO/plutus/pull/7236
 constraints: setup.optparse-applicative >=0.19.0.0
 allow-newer: turtle:optparse-applicative
+
+if impl (ghc >= 9.14)
+  -- https://github.com/snowleopard/alga/issues/322
+  source-repository-package
+    type: git
+    location: https://github.com/snowleopard/alga/
+    tag: d4e43fb42db05413459fb2df493361d5a666588a
+
+-- cabal-allow-newer
+if impl (ghc >= 9.14)
+  allow-newer:
+    , Cabal:Cabal-syntax
+    , Cabal:containers
+    , OneTuple:base
+    , QuickCheck:splitmix
+    , aeson:OneTuple
+    , aeson:containers
+    , aeson:data-fix
+    , aeson:ghc-prim
+    , aeson:indexed-traversable
+    , aeson:scientific
+    , aeson:semialign
+    , aeson:template-haskell
+    , aeson:text-iso8601
+    , aeson:these
+    , aeson:time
+    , aeson:time-compat
+    , aeson:witherable
+    , assoc:base
+    , async:base
+    , base:ghc-prim
+    , bifunctors:template-haskell
+    , bin:base
+    , binary:containers
+    , binary-orphans:base
+    , boring:base
+    , brick:base
+    , canonical-json:containers
+    , cardano-crypto-class:io-classes
+    , cardano-prelude:base
+    , cborg:base
+    , cborg:containers
+    , cborg:ghc-prim
+    , concurrent-output:process
+    , config-ini:containers
+    , config-ini:text
+    , constraints-extras:base
+    , constraints-extras:template-haskell
+    , containers:base
+    , containers:template-haskell
+    , criterion:aeson
+    , data-default:containers
+    , data-default-class:data-default
+    , data-fix:base
+    , dec:base
+    , deepseq:base
+    , deepseq:ghc-prim
+    , dependent-map:containers
+    , deriving-compat:containers
+    , deriving-compat:template-haskell
+    , dictionary-sharing:containers
+    , directory:base
+    , directory:time
+    , dom-lt:containers
+    , fin:base
+    , fin:universe-base
+    , foldl:containers
+    , free:containers
+    , free:template-haskell
+    , generically:base
+    , ghc-heap:containers
+    , hashable:base
+    , hashable:containers
+    , hashable:ghc-bignum
+    , hedgehog:containers
+    , hedgehog:template-haskell
+    , hedgehog:time
+    , hedgehog-fn:hedgehog
+    , hsc2hs:base
+    , indexed-traversable:base
+    , indexed-traversable:containers
+    , indexed-traversable-instances:base
+    , integer-conversion:base
+    , integer-logarithms:base
+    , integer-logarithms:ghc-bignum
+    , io-classes:base
+    , io-classes:time
+    , lens:containers
+    , lens:free
+    , lens:template-haskell
+    , list-t:foldl
+    , megaparsec:base
+    , megaparsec:containers
+    , megaparsec:transformers
+    , microlens-mtl:microlens
+    , microlens-th:containers
+    , microlens-th:template-haskell
+    , microstache:aeson
+    , microstache:base
+    , microstache:containers
+    , microstache:unordered-containers
+    , microstache:vector
+    , monoidal-containers:base
+    , monoidal-containers:containers
+    , network-uri:th-compat
+    , nonempty-vector:base
+    , nothunks:containers
+    , nothunks:time
+    , nothunks:wherefrom-compat
+    , ordered-containers:containers
+    , os-string:template-haskell
+    , parallel:base
+    , parsec:text
+    , plutus-core:dependent-map
+    , plutus-core:microlens-th
+    , plutus-core:vty
+    , primitive:base
+    , process:base
+    , process:unix
+    , quickcheck-instances:base
+    , quickcheck-instances:containers
+    , ral:base
+    , ral:boring
+    , recursion-schemes:containers
+    , recursion-schemes:template-haskell
+    , scientific:base
+    , scientific:containers
+    , scientific:integer-logarithms
+    , scientific:template-haskell
+    , semialign:base
+    , semialign:containers
+    , semigroupoids:bifunctors
+    , serialise:base
+    , serialise:containers
+    , serialise:ghc-prim
+    , serialise:time
+    , singletons:base
+    , singletons-th:base
+    , singletons-th:singletons
+    , singletons-th:template-haskell
+    , singletons-th:th-desugar
+    , singletons-th:th-orphans
+    , size-based:template-haskell
+    , some:base
+    , splitmix:base
+    , statistics:parallel
+    , tagged:base
+    , tagged:template-haskell
+    , tasty:base
+    , tasty:tagged
+    , tasty-golden:tasty
+    , tasty-hedgehog:base
+    , tasty-hedgehog:hedgehog
+    , test-framework:time
+    , text:binary
+    , text:bytestring
+    , text:template-haskell
+    , text-iso8601:time
+    , text-short:base
+    , text-short:bytestring
+    , text-short:ghc-prim
+    , text-short:template-haskell
+    , th-abstraction:template-haskell
+    , th-compat:template-haskell
+    , th-desugar:template-haskell
+    , th-expand-syns:base
+    , th-expand-syns:containers
+    , th-expand-syns:template-haskell
+    , th-lift:template-haskell
+    , th-lift-instances:th-lift
+    , th-orphans:template-haskell
+    , these:base
+    , time-compat:base
+    , time-compat:deepseq
+    , time-compat:time
+    , transformers:base
+    , tree-diff:QuickCheck
+    , tree-diff:base
+    , tree-diff:containers
+    , tree-diff:time
+    , turtle:containers
+    , turtle:time
+    , typed-process:async
+    , universe-base:base
+    , universe-base:containers
+    , unix:time
+    , unordered-containers:hashable
+    , unordered-containers:template-haskell
+    , uuid-types:template-haskell
+    , vector-th-unbox:base
+    , vector-th-unbox:template-haskell
+    , wherefrom-compat:base
+    , wherefrom-compat:ghc-heap
+    , witherable:containers

plutus-core/plutus-core/src/PlutusCore/Core/Instance/Eq.hs

@@ -3,6 +3,7 @@
 
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 
+{-# LANGUAGE CPP                  #-}
 {-# LANGUAGE FlexibleInstances    #-}
 {-# LANGUAGE RankNTypes           #-}
 {-# LANGUAGE TypeApplications     #-}
@@ -51,9 +52,14 @@ deriving stock instance
    (GEq uni, Closed uni, uni `Everywhere` Eq, Eq ann) =>
    Eq (Type TyDeBruijn uni ann)
 
-deriving stock instance (GEq uni, Closed uni, uni `Everywhere` Eq, Eq fun, Eq ann,
-                  Eq (Term tyname name uni fun ann)
-                  ) =>  Eq (Program tyname name uni fun ann)
+deriving stock instance (
+#if __GLASGOW_HASKELL__ < 914
+  -- These constraints are REQUIERD for ghc < 9.14 but REDUNDANT for ghc >= 9.14
+  -- See https://gitlab.haskell.org/ghc/ghc/-/issues/26381#note_637863
+  GEq uni, Closed uni, Eq fun,
+#endif
+  uni `Everywhere` Eq, Eq ann,
+                  Eq (Term tyname name uni fun ann)                  ) =>  Eq (Program tyname name uni fun ann)
 
 type EqRenameOf ren a = HasUniques a => a -> a -> EqRename ren
 

plutus-core/plutus-core/src/PlutusCore/Error.hs

@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP                    #-}
 {-# LANGUAGE DeriveAnyClass         #-}
 {-# LANGUAGE FlexibleInstances      #-}
 {-# LANGUAGE FunctionalDependencies #-}
@@ -10,6 +11,12 @@
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 -- appears in the generated instances
 
+#if __GLASGOW_HASKELL__ >= 914
+-- The `ghc-9.14` alpha release has what looks like a bug;
+-- https://gitlab.haskell.org/ghc/ghc/-/issues/26381
+{-# OPTIONS_GHC -Wno-redundant-constraints  #-}
+#endif
+
 module PlutusCore.Error
     ( ParserError (..)
     , ParserErrorBundle (..)

plutus-core/plutus-ir/src/PlutusIR/Core/Instance/Flat.hs

@@ -1,7 +1,15 @@
+{-# LANGUAGE CPP                  #-}
 {-# LANGUAGE DeriveAnyClass       #-}
 {-# LANGUAGE TypeOperators        #-}
 {-# LANGUAGE UndecidableInstances #-}
 {-# OPTIONS_GHC -Wno-orphans       #-}
+
+#if __GLASGOW_HASKELL__ >= 914
+-- The `ghc-9.14` alpha release has what looks like a bug;
+-- https://gitlab.haskell.org/ghc/ghc/-/issues/26381
+{-# OPTIONS_GHC -Wno-redundant-constraints  #-}
+#endif
+
 module PlutusIR.Core.Instance.Flat () where
 
 import PlutusIR.Core.Type

plutus-core/plutus-ir/test/PlutusCore/Generators/QuickCheck/SubstitutionTests.hs

@@ -1,4 +1,13 @@
 -- editorconfig-checker-disable-file
+
+{-# LANGUAGE CPP #-}
+
+#if __GLASGOW_HASKELL__ >= 914
+-- The `ghc-9.14` alpha release has what looks like a bug;
+-- https://gitlab.haskell.org/ghc/ghc/-/issues/26381
+{-# OPTIONS_GHC -Wno-redundant-constraints  #-}
+#endif
+
 module PlutusCore.Generators.QuickCheck.SubstitutionTests where
 
 import PlutusCore.Generators.QuickCheck

plutus-core/testlib/PlutusCore/Generators/QuickCheck/Common.hs

@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP                   #-}
 {-# LANGUAGE FlexibleInstances     #-}
 {-# LANGUAGE LambdaCase            #-}
 {-# LANGUAGE MultiParamTypeClasses #-}
@@ -6,6 +7,12 @@
 
 {-# OPTIONS_GHC -Wno-orphans #-}
 
+#if __GLASGOW_HASKELL__ >= 914
+-- The `ghc-9.14` alpha release has what looks like a bug;
+-- https://gitlab.haskell.org/ghc/ghc/-/issues/26381
+{-# OPTIONS_GHC -Wno-redundant-constraints  #-}
+#endif
+
 module PlutusCore.Generators.QuickCheck.Common where
 
 import PlutusPrelude

plutus-core/untyped-plutus-core/src/UntypedPlutusCore/Core/Instance/Eq.hs

@@ -1,6 +1,7 @@
 -- editorconfig-checker-disable-file
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 
+{-# LANGUAGE CPP                  #-}
 {-# LANGUAGE ConstraintKinds      #-}
 {-# LANGUAGE FlexibleInstances    #-}
 {-# LANGUAGE TypeOperators        #-}
@@ -65,7 +66,13 @@ deriving stock instance
 
 instance HashableTermConstraints uni fun ann => Hashable (Term DeBruijn uni fun ann)
 
-deriving stock instance (GEq uni, Closed uni, uni `Everywhere` Eq, Eq fun, Eq ann,
+deriving stock instance (
+#if __GLASGOW_HASKELL__ < 914
+  -- These constraints are REQUIERD for ghc < 9.14 but REDUNDANT for ghc >= 9.14
+  -- See https://gitlab.haskell.org/ghc/ghc/-/issues/26381#note_637863
+  GEq uni, Closed uni, Eq fun,
+#endif
+  uni `Everywhere` Eq, Eq ann,
                   Eq (Term name uni fun ann)
                   ) =>  Eq (Program name uni fun ann)
 

plutus-ledger-api/src/PlutusLedgerApi/V1/Interval.hs

@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP                  #-}
 {-# LANGUAGE DeriveAnyClass       #-}
 {-# LANGUAGE FlexibleInstances    #-}
 {-# LANGUAGE NoImplicitPrelude    #-}
@@ -13,6 +14,12 @@
 {-# LANGUAGE TypeFamilies         #-}
 {-# LANGUAGE TypeOperators        #-}
 
+#if __GLASGOW_HASKELL__ >= 914
+-- The `ghc-9.14` alpha release has what looks like a bug;
+-- https://gitlab.haskell.org/ghc/ghc/-/issues/26381
+{-# OPTIONS_GHC -Wno-redundant-constraints  #-}
+#endif
+
 -- | A type for intervals and associated functions.
 module PlutusLedgerApi.V1.Interval
     ( Interval(..)

plutus-tx/src/PlutusTx/Blueprint/Schema.hs

@@ -1,4 +1,5 @@
 {-# LANGUAGE AllowAmbiguousTypes   #-}
+{-# LANGUAGE CPP                   #-}
 {-# LANGUAGE DataKinds             #-}
 {-# LANGUAGE DeriveAnyClass        #-}
 {-# LANGUAGE DeriveDataTypeable    #-}
@@ -12,6 +13,12 @@
 {-# LANGUAGE TypeFamilies          #-}
 {-# LANGUAGE UndecidableInstances  #-}
 
+#if __GLASGOW_HASKELL__ >= 914
+-- The `ghc-9.14` alpha release has what looks like a bug;
+-- https://gitlab.haskell.org/ghc/ghc/-/issues/26381
+{-# OPTIONS_GHC -Wno-redundant-constraints  #-}
+#endif
+
 module PlutusTx.Blueprint.Schema where
 
 import Control.Lens.Plated (Plated)

plutus-tx/src/PlutusTx/Builtins/HasOpaque.hs

@@ -11,6 +11,12 @@
 {-# OPTIONS_GHC -fno-omit-interface-pragmas #-}
 {-# OPTIONS_GHC -fno-specialise #-}
 
+#if __GLASGOW_HASKELL__ >= 914
+-- The `ghc-9.14` alpha release has what looks like a bug;
+-- https://gitlab.haskell.org/ghc/ghc/-/issues/26381
+{-# OPTIONS_GHC -Wno-redundant-constraints  #-}
+#endif
+
 module PlutusTx.Builtins.HasOpaque where
 
 import Control.DeepSeq (NFData (..))