[commit: ghc] master: use Proxy instead of undefined -- we already dropped support for 7.6 (7aea0cf)

[git at git.haskell.org]

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

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/7aea0cfa609c8750ad256f5b2a6583444a907bf6/ghc

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

commit 7aea0cfa609c8750ad256f5b2a6583444a907bf6
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Sat Oct 24 12:05:41 2015 +0200

    use Proxy instead of undefined -- we already dropped support for 7.6
    
    Reviewers: austin, goldfire, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: thomie
    
    Differential Revision: https://phabricator.haskell.org/D1363


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

7aea0cfa609c8750ad256f5b2a6583444a907bf6
 compiler/typecheck/TcSplice.hs | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/compiler/typecheck/TcSplice.hs b/compiler/typecheck/TcSplice.hs
index 12f28a5..728c40a 100644
--- a/compiler/typecheck/TcSplice.hs
+++ b/compiler/typecheck/TcSplice.hs
@@ -109,8 +109,9 @@ import GHC.Desugar      ( AnnotationWrapper(..) )
 
 import qualified Data.Map as Map
 import Data.Dynamic  ( fromDynamic, toDyn )
-import Data.Typeable ( typeOf, Typeable )
+import Data.Typeable ( typeOf, Typeable, typeRep )
 import Data.Data (Data)
+import Data.Proxy    ( Proxy (..) )
 import GHC.Exts         ( unsafeCoerce# )
 #endif
 
@@ -844,9 +845,7 @@ instance TH.Quasi (IOEnv (Env TcGblEnv TcLclEnv)) where
       th_state_var <- fmap tcg_th_state getGblEnv
       th_state <- readTcRef th_state_var
       -- See #10596 for why we use a scoped type variable here.
-      -- ToDo: convert @undefined :: a@ to @proxy :: Proxy a@ when
-      -- we drop support for GHC 7.6.
-      return (Map.lookup (typeOf (undefined :: a)) th_state >>= fromDynamic)
+      return (Map.lookup (typeRep (Proxy :: Proxy a)) th_state >>= fromDynamic)
 
   qPutQ x = do
       th_state_var <- fmap tcg_th_state getGblEnv