From 5f9bd6b8297d4674cd19a18896c61b7c7b17c800 Mon Sep 17 00:00:00 2001
From: Neil Brown <neil@twistedsquare.com>
Date: Thu, 20 Nov 2008 14:31:29 +0000
Subject: [PATCH] Fixed checkUnusedVar to also remove the unused variable from
 the compiler state

---
 checks/Check.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/checks/Check.hs b/checks/Check.hs
index d0ecb64..5e4519a 100644
--- a/checks/Check.hs
+++ b/checks/Check.hs
@@ -23,6 +23,7 @@ with this program.  If not, see <http://www.gnu.org/licenses/>.
 module Check (checkInitVarPass, usageCheckPass, checkUnusedVar) where
 
 import Control.Monad.Identity
+import Control.Monad.State
 import Control.Monad.Trans
 import Data.Generics
 import Data.Graph.Inductive
@@ -284,6 +285,7 @@ checkUnusedVar = forAnyASTStruct doSpec
                do -- TODO have a more general way of not warning about compiler-generated names:
                   when (not $ "_sizes" `isSuffixOf` A.nameName name) $
                     warnPC mspec WarnUnusedVariable $ formatCode "Unused variable: %" name
+                  modify (\st -> st { csNames = Map.delete (A.nameName name) (csNames st) })
                   substitute scope
     doSpec _ = return ()