[commit: ghc] ghc-8.0: Add missing kind cast to pure unifier. (c88cd45)

[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/c88cd459c97b0c32221721e75c823c8a7064b0a1/ghc

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commit c88cd459c97b0c32221721e75c823c8a7064b0a1
Author: Richard Eisenberg <eir at cis.upenn.edu>
Date:   Sat Jan 30 16:49:22 2016 -0500

    Add missing kind cast to pure unifier.
    
    (cherry picked from commit aff5bb47b70450bb1e3e4ac3c18ea35d13f9ac7c)


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c88cd459c97b0c32221721e75c823c8a7064b0a1
 compiler/types/Unify.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compiler/types/Unify.hs b/compiler/types/Unify.hs
index 271ddb6..2eb38c8 100644
--- a/compiler/types/Unify.hs
+++ b/compiler/types/Unify.hs
@@ -796,7 +796,7 @@ uVar tv1 ty kco
                                 -- this is because the range of the subst is the target
                                 -- type, not the template type. So, just check for
                                 -- normal type equality.
-                                guard (ty' `eqType` ty) }
+                                guard ((ty' `mkCastTy` kco) `eqType` ty) }
           Nothing  -> uUnrefined tv1 ty ty kco } -- No, continue
 
 uUnrefined :: TyVar             -- variable to be unified