[commit: ghc] ghc-8.0: Make exactTyCoVarsOfTypes closed over kinds. (01d0079)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : ghc-8.0
Link       : http://ghc.haskell.org/trac/ghc/changeset/01d00798aae96af9e58e5f115e9dec93bf0c2baf/ghc

>---------------------------------------------------------------

commit 01d00798aae96af9e58e5f115e9dec93bf0c2baf
Author: Richard Eisenberg <eir at cis.upenn.edu>
Date:   Thu Jan 28 17:39:03 2016 -0500

    Make exactTyCoVarsOfTypes closed over kinds.
    
    (cherry picked from commit b962bcc609cf3239d61ba281ca0eccc3cd89d99d)


>---------------------------------------------------------------

01d00798aae96af9e58e5f115e9dec93bf0c2baf
 compiler/typecheck/TcType.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compiler/typecheck/TcType.hs b/compiler/typecheck/TcType.hs
index a91f407..b52681a 100644
--- a/compiler/typecheck/TcType.hs
+++ b/compiler/typecheck/TcType.hs
@@ -750,7 +750,7 @@ exactTyCoVarsOfType ty
   = go ty
   where
     go ty | Just ty' <- coreView ty = go ty'  -- This is the key line
-    go (TyVarTy tv)         = unitVarSet tv
+    go (TyVarTy tv)         = unitVarSet tv `unionVarSet` go (tyVarKind tv)
     go (TyConApp _ tys)     = exactTyCoVarsOfTypes tys
     go (LitTy {})           = emptyVarSet
     go (AppTy fun arg)      = go fun `unionVarSet` go arg