X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Fspecialise%2FRules.lhs;h=24c400491ce85b5d1c12281bb18311cdea097b65;hb=4e4d8e70295de6dcfaa77de4e7ce89123a3d190d;hp=fb0ad4012457d563d2cf77a4f0943fb12d47e186;hpb=de905f504a3e129e2c4a1906d7e0a26e36cd6c4b;p=ghc-hetmet.git

diff --git a/compiler/specialise/Rules.lhs b/compiler/specialise/Rules.lhs
index fb0ad40..24c4004 100644
--- a/compiler/specialise/Rules.lhs
+++ b/compiler/specialise/Rules.lhs
@@ -4,6 +4,13 @@
 \section[CoreRules]{Transformation rules}
 
 \begin{code}
+{-# OPTIONS -w #-}
+-- The above warning supression flag is a temporary kludge.
+-- While working on this module you are encouraged to remove it and fix
+-- any warnings in the module. See
+--     http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
+-- for details
+
 module Rules (
 	RuleBase, emptyRuleBase, mkRuleBase, extendRuleBaseList, 
 	unionRuleBase, pprRuleBase, ruleCheckProgram,
@@ -20,7 +27,7 @@ module Rules (
 
 import CoreSyn		-- All of it
 import OccurAnal	( occurAnalyseExpr )
-import CoreFVs		( exprFreeVars, exprsFreeVars, bindFreeVars, rulesRhsFreeVars )
+import CoreFVs		( exprFreeVars, exprsFreeVars, bindFreeVars, rulesFreeVars )
 import CoreUnfold	( isCheapUnfolding, unfoldingTemplate )
 import CoreUtils	( tcEqExprX, exprType )
 import PprCore		( pprRules )
@@ -45,7 +52,7 @@ import Maybes
 import OrdList
 import Bag
 import Util
-import List hiding( mapAccumL )	-- Also defined in Util
+import Data.List
 \end{code}
 
 
@@ -136,11 +143,11 @@ ruleCantMatch ts	     as		    = False
 
 \begin{code}
 mkSpecInfo :: [CoreRule] -> SpecInfo
-mkSpecInfo rules = SpecInfo rules (rulesRhsFreeVars rules)
+mkSpecInfo rules = SpecInfo rules (rulesFreeVars rules)
 
 extendSpecInfo :: SpecInfo -> [CoreRule] -> SpecInfo
 extendSpecInfo (SpecInfo rs1 fvs1) rs2
-  = SpecInfo (rs2 ++ rs1) (rulesRhsFreeVars rs2 `unionVarSet` fvs1)
+  = SpecInfo (rs2 ++ rs1) (rulesFreeVars rs2 `unionVarSet` fvs1)
 
 addSpecInfo :: SpecInfo -> SpecInfo -> SpecInfo
 addSpecInfo (SpecInfo rs1 fvs1) (SpecInfo rs2 fvs2) 
@@ -588,11 +595,8 @@ match menv subst (Type ty1) (Type ty2)
   = match_ty menv subst ty1 ty2
 
 match menv subst (Cast e1 co1) (Cast e2 co2)
-  | (from1, to1) <- coercionKind co1
-  , (from2, to2) <- coercionKind co2
-  = do	{ subst1 <- match_ty menv subst  to1   to2
-	; subst2 <- match_ty menv subst1 from1 from2
-	; match menv subst2 e1 e2 }
+  = do	{ subst1 <- match_ty menv subst co1 co2
+	; match menv subst1 e1 e2 }
 
 {-	REMOVING OLD CODE: I think that the above handling for let is 
 			   better than the stuff here, which looks 
@@ -639,6 +643,8 @@ match_var menv subst@(tv_subst, id_subst, binds) v1 e2
 
 		| otherwise	-- No renaming to do on e2, because no free var
 				-- of e2 is in the rnEnvR of the envt
+		-- Note [Matching variable types]
+		-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 		-- However, we must match the *types*; e.g.
 		--   forall (c::Char->Int) (x::Char). 
 		--	f (c x) = "RULE FIRED"