#15825: Core Lint error from Explicit Foralls Proposal -------------------------------------+------------------------------------- Reporter: Iceland_jack | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.6.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- This is using the recent Explicit Foralls Proposal #14268 {{{#!hs {-# Language RankNTypes #-} {-# Language PolyKinds #-} {-# Language KindSignatures #-} {-# Language DataKinds #-} {-# Language FlexibleInstances #-} {-# Options_GHC -dcore-lint #-} type C k = (forall (x::k). *) class X (a :: *) instance forall (a :: C k). X (a :: *) }}} {{{ $ ./inplace/bin/ghc-stage2 --interactive -ignore-dot-ghci /tmp/599_bug.hs GHCi, version 8.7.20181025: http://www.haskell.org/ghc/ :? for help [1 of 1] Compiling Main ( 599_bug.hs, interpreted ) *** Core Lint errors : in result of Desugar (before optimization) *** <no location info>: warning: In the expression: C:X @ a_a1yJ Kind application error in type ‘a_a1yJ’ Function kind = C k_a1yI Arg kinds = [(x_a1yH, k_a1yG)] Forall: x_a1xE k_a1yI (x_a1yH, k_a1yG) <no location info>: warning: In the expression: C:X @ a_a1xG Kind application error in type ‘a_a1xG’ Function kind = C k_X1xQ Arg kinds = [(x_a1yv, k_a1xF)] Forall: x_a1xE k_X1xQ (x_a1yv, k_a1xF) *** Offending Program *** Rec { $tcX :: TyCon [LclIdX] $tcX = TyCon 6136962148358085538## 2047526523769221729## $trModule (TrNameS "X"#) 0# $krep_a1zH $tc'C:X :: TyCon [LclIdX] $tc'C:X = TyCon 12994509767826319747## 2028070155085790741## $trModule (TrNameS "'C:X"#) 1# $krep_a1zJ $krep_a1zK [InlPrag=NOUSERINLINE[~]] :: KindRep [LclId] $krep_a1zK = $WKindRepVar (I# 0#) $krep_a1zH [InlPrag=NOUSERINLINE[~]] :: KindRep [LclId] $krep_a1zH = KindRepFun krep$* $krep_a1zI $krep_a1zI [InlPrag=NOUSERINLINE[~]] :: KindRep [LclId] $krep_a1zI = KindRepTyConApp $tcConstraint ([] @ KindRep) $krep_a1zJ [InlPrag=NOUSERINLINE[~]] :: KindRep [LclId] $krep_a1zJ = KindRepTyConApp $tcX (: @ KindRep $krep_a1zK ([] @ KindRep)) $trModule :: Module [LclIdX] $trModule = Module (TrNameS "main"#) (TrNameS "Main"#) $fXa [InlPrag=NOUSERINLINE CONLIKE] :: forall k (x :: k) k (a :: C k). X a [LclIdX[DFunId], Unf=DFun: \ (@ k_a1xF) (@ (x_a1yv :: k_a1xF)) (@ k_a1xF) (@ (a_a1xG :: C k_a1xF)) -> C:X TYPE: a_a1xG] $fXa = \ (@ k_a1yG) (@ (x_a1yH :: k_a1yG)) (@ k_a1yI) (@ (a_a1yJ :: C k_a1yI)) -> C:X @ a_a1yJ end Rec } *** End of Offense *** <no location info>: error: Compilation had errors *** Exception: ExitFailure 1

}}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15825 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler