X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2FsimplCore%2FOccurAnal.lhs;h=4082fcc757a7a35d7eec4acf4fba6223d626bdae;hb=f37e239fb5e81fc493e0ea1af98178bf1f7ceaba;hp=8e199331e25cacb95c2f9fd753b55c1c790d693d;hpb=098d99aa2967cd35bdfe2a8c48ea8eee8ffd4f11;p=ghc-hetmet.git

diff --git a/compiler/simplCore/OccurAnal.lhs b/compiler/simplCore/OccurAnal.lhs
index 8e19933..4082fcc 100644
--- a/compiler/simplCore/OccurAnal.lhs
+++ b/compiler/simplCore/OccurAnal.lhs
@@ -455,6 +455,11 @@ occAnal env (Note note body)
   = case occAnal env body of { (usage, body') ->
     (usage, Note note body')
     }
+
+occAnal env (Cast expr co)
+  = case occAnal env expr of { (usage, expr') ->
+    (usage, Cast expr' co)
+    }
 \end{code}
 
 \begin{code}
@@ -632,15 +637,22 @@ is rather like
 If e turns out to be (e1,e2) we indeed get something like
 	let a = e1; b = e2; x = (a,b) in rhs
 
+Note [Aug 06]: I don't think this is necessary any more, and it helpe
+	       to know when binders are unused.  See esp the call to
+	       isDeadBinder in Simplify.mkDupableAlt
+
 \begin{code}
 occAnalAlt env case_bndr (con, bndrs, rhs)
   = case occAnal env rhs of { (rhs_usage, rhs') ->
     let
         (final_usage, tagged_bndrs) = tagBinders rhs_usage bndrs
+	final_bndrs = tagged_bndrs	-- See Note [Aug06] above
+{-
 	final_bndrs | case_bndr `elemVarEnv` final_usage = bndrs
 		    | otherwise				= tagged_bndrs
 		-- Leave the binders untagged if the case 
 		-- binder occurs at all; see note above
+-}
     in
     (final_usage, (con, final_bndrs, rhs')) }
 \end{code}