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Resolving dependencies...
Starting     constr-eq-0.1.0.0
Building     constr-eq-0.1.0.0
Failed to install constr-eq-0.1.0.0
Build log ( /home/builder/.cabal/logs/ghc-8.6.3/constr-eq-0.1.0.0-CkICDuwbHfmDwCsqnR2Rgy.log ):
cabal: Entering directory '/tmp/cabal-tmp-17226/constr-eq-0.1.0.0'
Configuring constr-eq-0.1.0.0...
Preprocessing library for constr-eq-0.1.0.0..
Building library for constr-eq-0.1.0.0..
[1 of 1] Compiling Generics.Deriving.ConstrEq ( src/Generics/Deriving/ConstrEq.hs, dist/build/Generics/Deriving/ConstrEq.o )

src/Generics/Deriving/ConstrEq.hs:52:53: error:
    Illegal operator ‘:+:’ in type ‘f :+: g’
      Use TypeOperators to allow operators in types
   |
52 | instance (ConstrEq' f, ConstrEq' g) => ConstrEq' (f :+: g) where
   |                                                     ^^^

src/Generics/Deriving/ConstrEq.hs:57:23: error:
    Illegal operator ‘:*:’ in type ‘f :*: g’
      Use TypeOperators to allow operators in types
   |
57 | instance ConstrEq' (f :*: g) where
   |                       ^^^

src/Generics/Deriving/ConstrEq.hs:63:5: error:
    Unexpected default signature:
      default constrEq ::
                (Generic a, ConstrEq' (Rep a)) => a -> a -> Bool
    Use DefaultSignatures to enable default signatures
   |
63 |     default constrEq :: (Generic a, ConstrEq' (Rep a)) => a -> a -> Bool
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
cabal: Leaving directory '/tmp/cabal-tmp-17226/constr-eq-0.1.0.0'
cabal: Error: some packages failed to install:
constr-eq-0.1.0.0-CkICDuwbHfmDwCsqnR2Rgy failed during the building phase. The
exception was:
ExitFailure 1