[GHC] #15788: Core Lint error, from visible kind applications

[GHC]

#15788: Core Lint error, from visible kind applications
-------------------------------------+-------------------------------------
           Reporter:  Iceland_jack   |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.6.1
           Keywords:  #12045         |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 {{{#!hs
 {-# Language RankNTypes       #-}
 {-# Language GADTs            #-}
 {-# Language TypeApplications #-}
 {-# Language PolyKinds        #-}

 {-# Options_GHC -dcore-lint #-}

 import Data.Kind

 data A :: forall k. Type where
  MkA :: A @k
 }}}

 this cute bug crashes under the [https://phabricator.haskell.org/D5229
 visible kind application] diff, produces:

 {{{
 $ ghci -ignore-dot-ghci 545_bug.hs
 GHCi, version 8.7.20181017: http://www.haskell.org/ghc/  :? for help
 [1 of 1] Compiling Main             ( 545_bug.hs, interpreted )
 *** Core Lint errors : in result of Tidy Core ***
 <no location info>: warning:
     In the type ‘forall (k :: k_a1xN[sk:1]) k. A’
     @ k_a1xN[sk:1] is out of scope
 *** Offending Program ***
 $WMkA [InlPrag=INLINE[2]] :: forall (k :: k_a1xN[sk:1]) k. A
 [GblId[DataConWrapper],
  Caf=NoCafRefs,
  Unf=Unf{Src=InlineStable, TopLvl=True, Value=True, ConLike=True,
          WorkFree=True, Expandable=True,
          Guidance=ALWAYS_IF(arity=0,unsat_ok=True,boring_ok=True)
          Tmpl= \ (@ (k_a1y5 :: k_a1xN[sk:1])) (@ k_X1xP) ->
                  MkA @ k_X1xP @ k_a1y5}]
 $WMkA
   = \ (@ (k_a1y5 :: k_a1xN[sk:1])) (@ k_X1xP) ->
       MkA @ k_X1xP @ k_a1y5

 $trModule1_r1zb :: Addr#
 [GblId, Caf=NoCafRefs, Unf=OtherCon []]
 $trModule1_r1zb = "main"#

 $trModule2_r1zu :: TrName
 [GblId, Caf=NoCafRefs, Unf=OtherCon []]
 $trModule2_r1zu = TrNameS $trModule1_r1zb

 $trModule3_r1zv :: Addr#
 [GblId, Caf=NoCafRefs, Unf=OtherCon []]
 $trModule3_r1zv = "Main"#

 $trModule4_r1zw :: TrName
 [GblId, Caf=NoCafRefs, Unf=OtherCon []]
 $trModule4_r1zw = TrNameS $trModule3_r1zv

 $trModule :: Module
 [GblId, Caf=NoCafRefs, Unf=OtherCon []]
 $trModule = Module $trModule2_r1zu $trModule4_r1zw

 $krep_r1zx :: KindRep
 [GblId, Caf=NoCafRefs, Unf=OtherCon []]
 $krep_r1zx = KindRepVar 1#

 $krep1_r1zy :: KindRep
 [GblId, Caf=NoCafRefs, Unf=OtherCon []]
 $krep1_r1zy = KindRepVar 0#

 $tcA1_r1zz :: Addr#
 [GblId, Caf=NoCafRefs, Unf=OtherCon []]
 $tcA1_r1zz = "A"#

 $tcA2_r1zA :: TrName
 [GblId, Caf=NoCafRefs, Unf=OtherCon []]
 $tcA2_r1zA = TrNameS $tcA1_r1zz

 $tcA :: TyCon
 [GblId, Unf=OtherCon []]
 $tcA
   = TyCon
       16201120719427956884##
       13080046616073797921##
       $trModule
       $tcA2_r1zA
       2#
       krep$*

 $krep2_r1zB :: [KindRep]
 [GblId, Caf=NoCafRefs, Unf=OtherCon []]
 $krep2_r1zB = : @ KindRep $krep1_r1zy ([] @ KindRep)

 $krep3_r1zC :: [KindRep]
 [GblId, Caf=NoCafRefs, Unf=OtherCon []]
 $krep3_r1zC = : @ KindRep $krep_r1zx $krep2_r1zB

 $krep4_r1zD :: KindRep
 [GblId, Unf=OtherCon []]
 $krep4_r1zD = KindRepTyConApp $tcA $krep3_r1zC

 $tc'MkA1_r1zE :: Addr#
 [GblId, Caf=NoCafRefs, Unf=OtherCon []]
 $tc'MkA1_r1zE = "'MkA"#

 $tc'MkA2_r1zF :: TrName
 [GblId, Caf=NoCafRefs, Unf=OtherCon []]
 $tc'MkA2_r1zF = TrNameS $tc'MkA1_r1zE

 $tc'MkA :: TyCon
 [GblId, Unf=OtherCon []]
 $tc'MkA
   = TyCon
       1695572187443655535##
       16213897990811765752##
       $trModule
       $tc'MkA2_r1zF
       2#
       $krep4_r1zD

 *** End of Offense ***


 <no location info>: error:
 Compilation had errors


 *** Exception: ExitFailure 1
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15788>
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