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When compiling primitive-0.5.1.0 with --ghc-option=-dcore-lint,

GHC 7.4.2 just emits a single warning:

[10 of 10] Compiling Data.Primitive.MutVar ( Data/Primitive/MutVar.hs, dist/build/Data/Primitive/MutVar.o )
*** Core Lint warnings : in result of Desugar (after optimization) ***
<no location info>:
    [RHS of $c/=_a724 :: forall s_a70h a_a70i.
                         Data.Primitive.MutVar.MutVar s_a70h a_a70i
                         -> Data.Primitive.MutVar.MutVar s_a70h a_a70i -> GHC.Types.Bool]
    INLINE binder is (non-rule) loop breaker: $c/=_a724

However, with GHC 7.6.3, an error is produced:

[ 5 of 10] Compiling Data.Primitive.Types ( Data/Primitive/Types.hs, dist/build/Data/Primitive/Types.o )
*** Core Lint errors : in result of Desugar (after optimization) ***
<no location info>: Warning:
    In the type `GHC.Prim.State# GHC.Prim.RealWorld
                 ~ GHC.Prim.State# (Control.Monad.Primitive.PrimState GHC.Types.IO)'
    Kind application error in
      type `GHC.Prim.State# GHC.Prim.RealWorld
            ~ GHC.Prim.State# (Control.Monad.Primitive.PrimState GHC.Types.IO)'
      Function kind = forall (k_1c :: BOX). k_1c -> k_1c -> Constraint
      Arg kinds = [(*, BOX), (GHC.Prim.State# GHC.Prim.RealWorld, #),
                   (GHC.Prim.State# (Control.Monad.Primitive.PrimState GHC.Types.IO),
                    #)]
<no location info>: Warning:
    In the type `GHC.Prim.State# GHC.Prim.RealWorld
                 ~ GHC.Prim.State# (Control.Monad.Primitive.PrimState GHC.Types.IO)'
    Kind application error in
      type `GHC.Prim.State# GHC.Prim.RealWorld
            ~ GHC.Prim.State# (Control.Monad.Primitive.PrimState GHC.Types.IO)'
      Function kind = forall (k_1c :: BOX). k_1c -> k_1c -> Constraint
      Arg kinds = [(*, BOX), (GHC.Prim.State# GHC.Prim.RealWorld, #),
                   (GHC.Prim.State# (Control.Monad.Primitive.PrimState GHC.Types.IO),
                    #)]
{-# LINE 142 "Data/Primitive/Types.hs #-}: Warning:
    [RHS of cobox_a2gR :: GHC.Prim.State# GHC.Prim.RealWorld
                          ~ GHC.Prim.State# (Control.Monad.Primitive.PrimState GHC.Types.IO)]
    The type of this binder doesn't match the type of its RHS: cobox_a2gR
    Binder's type: GHC.Prim.State# GHC.Prim.RealWorld
                   ~ GHC.Prim.State# (Control.Monad.Primitive.PrimState GHC.Types.IO)
    Rhs type: GHC.Prim.State# GHC.Prim.RealWorld
              ~ GHC.Prim.State# (Control.Monad.Primitive.PrimState GHC.Types.IO)

The core-lint error persists in GHC HEAD/7.7, blocking us from updating GHC's in-tree primitive/vector packages.

Trac metadata

Trac field	Value
Version	7.6.3
Type	Bug
TypeOfFailure	OtherFailure
Priority	highest
Resolution	Unresolved
Component	Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC	bos
Operating system
Architecture