[commit: ghc] wip/ttypeable: Fix up obviously incorrect comparisons (dfd90e2)

[git at git.haskell.org]

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

On branch  : wip/ttypeable
Link       : http://ghc.haskell.org/trac/ghc/changeset/dfd90e24ba3757128860890f09e4a6eb25320dcb/ghc

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

commit dfd90e24ba3757128860890f09e4a6eb25320dcb
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Sat Jan 28 10:52:31 2017 -0500

    Fix up obviously incorrect comparisons
    
    Up too late late night.


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

dfd90e24ba3757128860890f09e4a6eb25320dcb
 libraries/base/Data/Typeable/Internal.hs | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/libraries/base/Data/Typeable/Internal.hs b/libraries/base/Data/Typeable/Internal.hs
index 93eb2d3..aa04030 100644
--- a/libraries/base/Data/Typeable/Internal.hs
+++ b/libraries/base/Data/Typeable/Internal.hs
@@ -186,13 +186,15 @@ on f g = \ x y -> g x `f` g y
 
 -- | @since 2.01
 instance Eq (TypeRep a) where
-  TrTyCon a _ _ _ _ == TrTyCon b _ _ _ _  = a == b
+  _ == _  = True
   {-# INLINABLE (==) #-}
 
 instance TestEquality TypeRep where
-  testEquality (TrTyCon a _ _ _ _) (TrTyCon b _ _ _ _)
-    | a == b    = Just (unsafeCoerce# Refl)
-    | otherwise = Nothing
+  a `testEquality` b
+    | Just HRefl <- eqTypeRep a b
+    = Just Refl
+    | otherwise
+    = Nothing
   {-# INLINEABLE testEquality #-}
 
 -- | @since 4.4.0.0