Change how macros like ASSERT are defined

By using Haskell's debugIsOn rather than CPP's "#ifdef DEBUG", we
don't need to kludge things to keep the warning checker happy etc.

66 files changed, 73 insertions, 32 deletions

diff --git a/compiler/HsVersions.h b/compiler/HsVersions.h
index d85234784a..9a83af9768 100644
--- a/compiler/HsVersions.h
+++ b/compiler/HsVersions.h
@@ -46,18 +46,9 @@ name :: IORef (ty);                 \
 name = Util.globalM (value);
 #endif
 
-#ifdef DEBUG
-#define ASSERT(e)      if (not (e)) then (assertPanic __FILE__ __LINE__) else
-#define ASSERT2(e,msg) if (not (e)) then (assertPprPanic __FILE__ __LINE__ (msg)) else
+#define ASSERT(e)      if debugIsOn && not (e) then (assertPanic __FILE__ __LINE__) else
+#define ASSERT2(e,msg) if debugIsOn && not (e) then (assertPprPanic __FILE__ __LINE__ (msg)) else
 #define WARN( e, msg ) (warnPprTrace (e) __FILE__ __LINE__ (msg)) $
-#else
--- We have to actually use all the variables we are given or we may get
--- unused variable warnings when DEBUG is off.
-#define ASSERT(e)      if False && (not (e)) then panic "ASSERT" else
-#define ASSERT2(e,msg) if False && (const False (e,msg)) then pprPanic "ASSERT2" (msg) else
-#define WARN(e,msg)    if False && (e) then pprPanic "WARN" (msg) else
--- Here we deliberately don't use when as Control.Monad might not be imported
-#endif
 
 -- Examples:   Assuming   flagSet :: String -> m Bool
 -- 
diff --git a/compiler/basicTypes/Id.lhs b/compiler/basicTypes/Id.lhs
index d1df6cc0ab..299ea17d8f 100644
--- a/compiler/basicTypes/Id.lhs
+++ b/compiler/basicTypes/Id.lhs
@@ -126,7 +126,7 @@ import Outputable
 import Unique
 import UniqSupply
 import FastString
-import Util( count )
+import Util
 import StaticFlags
 
 -- infixl so you can say (id `set` a `set` b)
diff --git a/compiler/basicTypes/Literal.lhs b/compiler/basicTypes/Literal.lhs
index 966dca1e71..e29b49a9a5 100644
--- a/compiler/basicTypes/Literal.lhs
+++ b/compiler/basicTypes/Literal.lhs
@@ -62,6 +62,8 @@ import BasicTypes
 import Binary
 import Constants
 import UniqFM
+import Util
+
 import Data.Int
 import Data.Ratio
 import Data.Word
diff --git a/compiler/basicTypes/Unique.lhs b/compiler/basicTypes/Unique.lhs
index f99a50cfeb..7c0f26f4bf 100644
--- a/compiler/basicTypes/Unique.lhs
+++ b/compiler/basicTypes/Unique.lhs
@@ -71,6 +71,7 @@ import FastTypes
 import FastString
 import Outputable
 -- import StaticFlags
+import Util
 
 #if defined(__GLASGOW_HASKELL__)
 --just for implementing a fast [0,61) -> Char function
diff --git a/compiler/cmm/CmmBuildInfoTables.hs b/compiler/cmm/CmmBuildInfoTables.hs
index 27c9bcb2cf..b39a59134c 100644
--- a/compiler/cmm/CmmBuildInfoTables.hs
+++ b/compiler/cmm/CmmBuildInfoTables.hs
@@ -32,7 +32,7 @@ import Constants
 import Digraph
 import qualified Prelude as P
 import Prelude hiding (succ)
-import Util (sortLe)
+import Util
 
 import BlockId
 import Bitmap
diff --git a/compiler/cmm/CmmInfo.hs b/compiler/cmm/CmmInfo.hs
index a13ae12135..e4370696e1 100644
--- a/compiler/cmm/CmmInfo.hs
+++ b/compiler/cmm/CmmInfo.hs
@@ -27,6 +27,8 @@ import Platform
 import StaticFlags
 import UniqSupply
 import MonadUtils
+import Util
+
 import Data.Bits
 import Data.Word
 
diff --git a/compiler/cmm/CmmUtils.hs b/compiler/cmm/CmmUtils.hs
index 6d02e693fb..e5de4e551d 100644
--- a/compiler/cmm/CmmUtils.hs
+++ b/compiler/cmm/CmmUtils.hs
@@ -83,6 +83,7 @@ import OptimizationFuel as F
 import Unique
 import UniqSupply
 import Constants( wORD_SIZE, tAG_MASK )
+import Util
 
 import Data.Word
 import Data.Maybe
diff --git a/compiler/cmm/MkGraph.hs b/compiler/cmm/MkGraph.hs
index debc9e4a35..04586b1029 100644
--- a/compiler/cmm/MkGraph.hs
+++ b/compiler/cmm/MkGraph.hs
@@ -42,6 +42,7 @@ import SMRep (ByteOff)
 import StaticFlags
 import Unique
 import UniqSupply
+import Util
 
 #include "HsVersions.h"
 
diff --git a/compiler/cmm/OptimizationFuel.hs b/compiler/cmm/OptimizationFuel.hs
index f624c1c7b6..a85b11bcc6 100644
--- a/compiler/cmm/OptimizationFuel.hs
+++ b/compiler/cmm/OptimizationFuel.hs
@@ -22,6 +22,7 @@ import Control.Monad
 import StaticFlags (opt_Fuel)
 import UniqSupply
 import Panic
+import Util
 
 import Compiler.Hoopl
 import Compiler.Hoopl.GHC (getFuel, setFuel)
diff --git a/compiler/codeGen/CgMonad.lhs b/compiler/codeGen/CgMonad.lhs
index c0e3e3be8b..b96898f591 100644
--- a/compiler/codeGen/CgMonad.lhs
+++ b/compiler/codeGen/CgMonad.lhs
@@ -77,6 +77,7 @@ import VarEnv
 import OrdList
 import Unique
 import UniqSupply
+import Util
 import Outputable
 
 import Control.Monad
diff --git a/compiler/codeGen/CgTailCall.lhs b/compiler/codeGen/CgTailCall.lhs
index 499529d841..e933fedb5b 100644
--- a/compiler/codeGen/CgTailCall.lhs
+++ b/compiler/codeGen/CgTailCall.lhs
@@ -43,6 +43,7 @@ import StgSyn
 import PrimOp
 import Outputable
 import StaticFlags
+import Util
 
 import Control.Monad
 import Data.Maybe
diff --git a/compiler/codeGen/ClosureInfo.lhs b/compiler/codeGen/ClosureInfo.lhs
index d8fd07fead..23ae4270f4 100644
--- a/compiler/codeGen/ClosureInfo.lhs
+++ b/compiler/codeGen/ClosureInfo.lhs
@@ -96,6 +96,7 @@ import Outputable
 import FastString
 import Constants
 import DynFlags
+import Util
 \end{code}
 
 
diff --git a/compiler/codeGen/CodeGen.lhs b/compiler/codeGen/CodeGen.lhs
index aa561c4f40..24ac064256 100644
--- a/compiler/codeGen/CodeGen.lhs
+++ b/compiler/codeGen/CodeGen.lhs
@@ -45,6 +45,7 @@ import TyCon
 import Module
 import ErrUtils
 import Panic
+import Util
 
 codeGen :: DynFlags
         -> Module                     -- Module we are compiling
diff --git a/compiler/codeGen/StgCmm.hs b/compiler/codeGen/StgCmm.hs
index 7aa159844b..6e99543064 100644
--- a/compiler/codeGen/StgCmm.hs
+++ b/compiler/codeGen/StgCmm.hs
@@ -46,6 +46,7 @@ import TyCon
 import Module
 import ErrUtils
 import Outputable
+import Util
 
 codeGen :: DynFlags
 	 -> Module
diff --git a/compiler/codeGen/StgCmmClosure.hs b/compiler/codeGen/StgCmmClosure.hs
index d4ba62c6ca..708b2bd0a7 100644
--- a/compiler/codeGen/StgCmmClosure.hs
+++ b/compiler/codeGen/StgCmmClosure.hs
@@ -90,6 +90,7 @@ import Outputable
 import Platform
 import Constants
 import DynFlags
+import Util
 
 -----------------------------------------------------------------------------
 --		Representations
diff --git a/compiler/codeGen/StgCmmCon.hs b/compiler/codeGen/StgCmmCon.hs
index e17ac4fd32..ee71f5c86a 100644
--- a/compiler/codeGen/StgCmmCon.hs
+++ b/compiler/codeGen/StgCmmCon.hs
@@ -41,7 +41,7 @@ import PrelInfo
 import Outputable
 import Platform
 import StaticFlags
-import Util             ( lengthIs )
+import Util
 
 import Control.Monad
 import Data.Char
diff --git a/compiler/codeGen/StgCmmHeap.hs b/compiler/codeGen/StgCmmHeap.hs
index 690b0a9622..7b22c5726a 100644
--- a/compiler/codeGen/StgCmmHeap.hs
+++ b/compiler/codeGen/StgCmmHeap.hs
@@ -44,6 +44,7 @@ import Module
 import FastString( mkFastString, fsLit )
 import Constants
 import DynFlags
+import Util
 
 -----------------------------------------------------------
 --              Initialise dynamic heap objects
diff --git a/compiler/codeGen/StgCmmPrim.hs b/compiler/codeGen/StgCmmPrim.hs
index 331d4f529e..efa234b5a6 100644
--- a/compiler/codeGen/StgCmmPrim.hs
+++ b/compiler/codeGen/StgCmmPrim.hs
@@ -43,6 +43,7 @@ import Module
 import FastString
 import Outputable
 import StaticFlags
+import Util
 
 ------------------------------------------------------------------------
 --	Primitive operations and foreign calls
diff --git a/compiler/coreSyn/MkCore.lhs b/compiler/coreSyn/MkCore.lhs
index 53386fec02..3597df5b02 100644
--- a/compiler/coreSyn/MkCore.lhs
+++ b/compiler/coreSyn/MkCore.lhs
@@ -85,7 +85,7 @@ import Outputable
 import FastString
 import UniqSupply
 import BasicTypes
-import Util             ( notNull, zipEqual, sortLe )
+import Util
 import Pair
 import Constants
 
diff --git a/compiler/deSugar/DsCCall.lhs b/compiler/deSugar/DsCCall.lhs
index 2fff5fdb56..76bdfb930f 100644
--- a/compiler/deSugar/DsCCall.lhs
+++ b/compiler/deSugar/DsCCall.lhs
@@ -49,6 +49,7 @@ import PrelNames
 import VarSet
 import Constants
 import Outputable
+import Util
 \end{code}
 
 Desugaring of @ccall@s consists of adding some state manipulation,
diff --git a/compiler/deSugar/DsForeign.lhs b/compiler/deSugar/DsForeign.lhs
index be66b074f3..e5cd98f5f3 100644
--- a/compiler/deSugar/DsForeign.lhs
+++ b/compiler/deSugar/DsForeign.lhs
@@ -47,6 +47,8 @@ import Config
 import Constants
 import OrdList
 import Pair
+import Util
+
 import Data.Maybe
 import Data.List
 \end{code}
diff --git a/compiler/deSugar/DsListComp.lhs b/compiler/deSugar/DsListComp.lhs
index c3c52188fe..74fe642f1e 100644
--- a/compiler/deSugar/DsListComp.lhs
+++ b/compiler/deSugar/DsListComp.lhs
@@ -33,6 +33,7 @@ import SrcLoc
 import Outputable
 import FastString
 import TcType
+import Util
 \end{code}
 
 List comprehensions may be desugared in one of two ways: ``ordinary''
diff --git a/compiler/deSugar/DsMeta.hs b/compiler/deSugar/DsMeta.hs
index 625c17ab33..9a1d050fb2 100644
--- a/compiler/deSugar/DsMeta.hs
+++ b/compiler/deSugar/DsMeta.hs
@@ -65,7 +65,7 @@ import Bag
 import FastString
 import ForeignCall
 import MonadUtils
-import Util( equalLength, filterOut )
+import Util
 
 import Data.Maybe
 import Control.Monad
diff --git a/compiler/deSugar/MatchCon.lhs b/compiler/deSugar/MatchCon.lhs
index 29c10bdb48..e1b2ef83df 100644
--- a/compiler/deSugar/MatchCon.lhs
+++ b/compiler/deSugar/MatchCon.lhs
@@ -26,7 +26,7 @@ import TcType
 import DsMonad
 import DsUtils
 import MkCore   ( mkCoreLets )
-import Util	( all2, takeList, zipEqual )
+import Util
 import ListSetOps ( runs )
 import Id
 import NameEnv
diff --git a/compiler/ghci/ByteCodeAsm.lhs b/compiler/ghci/ByteCodeAsm.lhs
index 93e6a8c188..5e5a5f0c62 100644
--- a/compiler/ghci/ByteCodeAsm.lhs
+++ b/compiler/ghci/ByteCodeAsm.lhs
@@ -34,6 +34,7 @@ import ClosureInfo -- CgRep stuff
 import DynFlags
 import Outputable
 import Platform
+import Util
 
 import Control.Monad
 import Control.Monad.ST ( runST )
diff --git a/compiler/ghci/ByteCodeLink.lhs b/compiler/ghci/ByteCodeLink.lhs
index d8235b6905..0087eb2994 100644
--- a/compiler/ghci/ByteCodeLink.lhs
+++ b/compiler/ghci/ByteCodeLink.lhs
@@ -27,6 +27,7 @@ import Module
 import FastString
 import Panic
 import Outputable
+import Util
 
 -- Standard libraries
 
diff --git a/compiler/hsSyn/HsExpr.lhs b/compiler/hsSyn/HsExpr.lhs
index 349c001cc8..c7f4459d6e 100644
--- a/compiler/hsSyn/HsExpr.lhs
+++ b/compiler/hsSyn/HsExpr.lhs
@@ -32,7 +32,7 @@ import Name
 import BasicTypes
 import DataCon
 import SrcLoc
-import Util( dropTail )
+import Util
 import StaticFlags( opt_PprStyle_Debug )
 import Outputable
 import FastString
diff --git a/compiler/iface/BinIface.hs b/compiler/iface/BinIface.hs
index 305fa54d0e..a69656533c 100644
--- a/compiler/iface/BinIface.hs
+++ b/compiler/iface/BinIface.hs
@@ -51,6 +51,7 @@ import Outputable
 import Platform
 import FastString
 import Constants
+import Util
 
 import Data.Bits
 import Data.Char
diff --git a/compiler/iface/BuildTyCl.lhs b/compiler/iface/BuildTyCl.lhs
index d41ee68d20..9456bdaf34 100644
--- a/compiler/iface/BuildTyCl.lhs
+++ b/compiler/iface/BuildTyCl.lhs
@@ -38,7 +38,7 @@ import Type
 import Coercion
 
 import TcRnMonad
-import Util		( isSingleton )
+import Util
 import Outputable
 \end{code}
 	
diff --git a/compiler/iface/IfaceEnv.lhs b/compiler/iface/IfaceEnv.lhs
index 4c66a98314..1e776f52a3 100644
--- a/compiler/iface/IfaceEnv.lhs
+++ b/compiler/iface/IfaceEnv.lhs
@@ -41,6 +41,7 @@ import FastString
 import UniqSupply
 import SrcLoc
 import BasicTypes
+import Util
 
 import Outputable
 import Exception     ( evaluate )
diff --git a/compiler/main/HscMain.hs b/compiler/main/HscMain.hs
index 8d190d4e5e..78e24c9aa9 100644
--- a/compiler/main/HscMain.hs
+++ b/compiler/main/HscMain.hs
@@ -147,6 +147,7 @@ import UniqFM           ( emptyUFM )
 import UniqSupply       ( initUs_ )
 import Bag
 import Exception
+import Util
 
 import Data.List
 import Control.Monad
diff --git a/compiler/nativeGen/PPC/CodeGen.hs b/compiler/nativeGen/PPC/CodeGen.hs
index 2b8bb62ad2..22406073b5 100644
--- a/compiler/nativeGen/PPC/CodeGen.hs
+++ b/compiler/nativeGen/PPC/CodeGen.hs
@@ -57,6 +57,7 @@ import Data.Word
 
 import BasicTypes
 import FastString
+import Util
 
 -- -----------------------------------------------------------------------------
 -- Top-level of the instruction selector
diff --git a/compiler/nativeGen/X86/CodeGen.hs b/compiler/nativeGen/X86/CodeGen.hs
index 98d5e892ad..4fa42820ca 100644
--- a/compiler/nativeGen/X86/CodeGen.hs
+++ b/compiler/nativeGen/X86/CodeGen.hs
@@ -54,6 +54,7 @@ import FastString
 import FastBool         ( isFastTrue )
 import Constants        ( wORD_SIZE )
 import DynFlags
+import Util
 
 import Control.Monad
 import Data.Bits
diff --git a/compiler/parser/RdrHsSyn.lhs b/compiler/parser/RdrHsSyn.lhs
index 350aedb6f0..6da712ce44 100644
--- a/compiler/parser/RdrHsSyn.lhs
+++ b/compiler/parser/RdrHsSyn.lhs
@@ -76,6 +76,8 @@ import Bag              ( Bag, emptyBag, consBag )
 import Outputable
 import FastString
 import Maybes
+import Util
+
 import Control.Applicative ((<$>))
 import Control.Monad
 import Text.ParserCombinators.ReadP as ReadP
diff --git a/compiler/prelude/PrelRules.lhs b/compiler/prelude/PrelRules.lhs
index fc0c20ad48..7e798be426 100644
--- a/compiler/prelude/PrelRules.lhs
+++ b/compiler/prelude/PrelRules.lhs
@@ -41,6 +41,7 @@ import FastString
 import StaticFlags ( opt_SimplExcessPrecision )
 import Constants
 import BasicTypes
+import Util
 
 import Data.Bits as Bits
 import Data.Int    ( Int64 )
diff --git a/compiler/prelude/TysWiredIn.lhs b/compiler/prelude/TysWiredIn.lhs
index 7a06bae163..f36e717950 100644
--- a/compiler/prelude/TysWiredIn.lhs
+++ b/compiler/prelude/TysWiredIn.lhs
@@ -104,6 +104,7 @@ import Data.Array
 import FastString
 import Outputable
 import Config
+import Util
 
 alpha_tyvar :: [TyVar]
 alpha_tyvar = [alphaTyVar]
diff --git a/compiler/profiling/SCCfinal.lhs b/compiler/profiling/SCCfinal.lhs
index 6fc44c1df9..a6fe565746 100644
--- a/compiler/profiling/SCCfinal.lhs
+++ b/compiler/profiling/SCCfinal.lhs
@@ -34,6 +34,7 @@ import Outputable
 import DynFlags
 import FastString
 import SrcLoc
+import Util
 
 
 stgMassageForProfiling
diff --git a/compiler/rename/RnExpr.lhs b/compiler/rename/RnExpr.lhs
index 78566de179..7ff7c7adec 100644
--- a/compiler/rename/RnExpr.lhs
+++ b/compiler/rename/RnExpr.lhs
@@ -46,7 +46,7 @@ import RdrName
 import LoadIface	( loadInterfaceForName )
 import UniqSet
 import Data.List
-import Util		( isSingleton, snocView )
+import Util
 import ListSetOps	( removeDups )
 import Outputable
 import SrcLoc
diff --git a/compiler/rename/RnPat.lhs b/compiler/rename/RnPat.lhs
index 3e3c2b66d2..df3566d73c 100644
--- a/compiler/rename/RnPat.lhs
+++ b/compiler/rename/RnPat.lhs
@@ -55,7 +55,7 @@ import Name
 import NameSet
 import RdrName
 import BasicTypes
-import Util		( notNull )
+import Util
 import ListSetOps	( removeDups )
 import Outputable
 import SrcLoc
diff --git a/compiler/rename/RnTypes.lhs b/compiler/rename/RnTypes.lhs
index 1b2e8417f3..ecdfdaf36e 100644
--- a/compiler/rename/RnTypes.lhs
+++ b/compiler/rename/RnTypes.lhs
@@ -49,7 +49,7 @@ import Name
 import SrcLoc
 import NameSet
 
-import Util		( filterOut )
+import Util
 import BasicTypes	( IPName(..), ipNameName, compareFixity, funTyFixity, negateFixity, 
 			  Fixity(..), FixityDirection(..) )
 import Outputable
diff --git a/compiler/simplCore/FloatIn.lhs b/compiler/simplCore/FloatIn.lhs
index c0c6478a7b..5a462443e2 100644
--- a/compiler/simplCore/FloatIn.lhs
+++ b/compiler/simplCore/FloatIn.lhs
@@ -31,7 +31,7 @@ import Id		( isOneShotBndr, idType )
 import Var
 import Type		( isUnLiftedType )
 import VarSet
-import Util		( zipEqual, zipWithEqual, count )
+import Util
 import UniqFM
 import Outputable
 \end{code}
diff --git a/compiler/simplCore/OccurAnal.lhs b/compiler/simplCore/OccurAnal.lhs
index e9ec0bea55..5a204f46b5 100644
--- a/compiler/simplCore/OccurAnal.lhs
+++ b/compiler/simplCore/OccurAnal.lhs
@@ -44,7 +44,7 @@ import Digraph          ( SCC(..), stronglyConnCompFromEdgedVerticesR )
 import PrelNames        ( buildIdKey, foldrIdKey, runSTRepIdKey, augmentIdKey )
 import Unique
 import UniqFM
-import Util             ( mapAndUnzip, filterOut, fstOf3 )
+import Util
 import Bag
 import Outputable
 import FastString
diff --git a/compiler/simplCore/SimplEnv.lhs b/compiler/simplCore/SimplEnv.lhs
index 8661d71e04..d6ba24d754 100644
--- a/compiler/simplCore/SimplEnv.lhs
+++ b/compiler/simplCore/SimplEnv.lhs
@@ -63,6 +63,7 @@ import BasicTypes
 import MonadUtils
 import Outputable
 import FastString
+import Util
 
 import Data.List
 \end{code}
diff --git a/compiler/simplCore/Simplify.lhs b/compiler/simplCore/Simplify.lhs
index 56e0bededd..726d0d5642 100644
--- a/compiler/simplCore/Simplify.lhs
+++ b/compiler/simplCore/Simplify.lhs
@@ -49,6 +49,7 @@ import Data.List        ( mapAccumL )
 import Outputable
 import FastString
 import Pair
+import Util
 \end{code}
 
 
diff --git a/compiler/stgSyn/StgSyn.lhs b/compiler/stgSyn/StgSyn.lhs
index defec7516b..a55a3ee2e6 100644
--- a/compiler/stgSyn/StgSyn.lhs
+++ b/compiler/stgSyn/StgSyn.lhs
@@ -67,6 +67,7 @@ import Type        ( Type )
 import Type        ( typePrimRep )
 import UniqSet
 import Unique      ( Unique )
+import Util
 import VarSet      ( IdSet, isEmptyVarSet )
 \end{code}
 
diff --git a/compiler/stranal/DmdAnal.lhs b/compiler/stranal/DmdAnal.lhs
index b85c107bea..ddeb1aa864 100644
--- a/compiler/stranal/DmdAnal.lhs
+++ b/compiler/stranal/DmdAnal.lhs
@@ -44,7 +44,7 @@ import UniqFM		( addToUFM_Directly, lookupUFM_Directly,
 			  minusUFM, filterUFM )
 import Type		( isUnLiftedType, eqType, tyConAppTyCon_maybe )
 import Coercion         ( coercionKind )
-import Util		( mapAndUnzip, lengthIs, zipEqual )
+import Util
 import BasicTypes	( Arity, TopLevelFlag(..), isTopLevel, isNeverActive,
 			  RecFlag(..), isRec, isMarkedStrict )
 import Maybes		( orElse, expectJust )
diff --git a/compiler/stranal/WorkWrap.lhs b/compiler/stranal/WorkWrap.lhs
index 2c365887bc..ec351ab7d8 100644
--- a/compiler/stranal/WorkWrap.lhs
+++ b/compiler/stranal/WorkWrap.lhs
@@ -27,7 +27,7 @@ import BasicTypes
 import VarEnv		( isEmptyVarEnv )
 import Maybes		( orElse )
 import WwLib
-import Util		( lengthIs, notNull )
+import Util
 import Outputable
 import MonadUtils
 
diff --git a/compiler/typecheck/FamInst.lhs b/compiler/typecheck/FamInst.lhs
index c43450cb17..b6370b5c92 100644
--- a/compiler/typecheck/FamInst.lhs
+++ b/compiler/typecheck/FamInst.lhs
@@ -28,7 +28,7 @@ import Outputable
 import UniqFM
 import VarSet
 import FastString
-import Util( filterOut, sortWith )
+import Util
 import Maybes
 import Control.Monad
 import Data.Map (Map)
diff --git a/compiler/typecheck/TcCanonical.lhs b/compiler/typecheck/TcCanonical.lhs
index 8a45632bfb..84a5c3dd72 100644
--- a/compiler/typecheck/TcCanonical.lhs
+++ b/compiler/typecheck/TcCanonical.lhs
@@ -36,7 +36,7 @@ import VarSet
 import TcSMonad
 import FastString
 
-import Util ( equalLength )
+import Util
 
 
 import TysWiredIn ( eqTyCon )
diff --git a/compiler/typecheck/TcClassDcl.lhs b/compiler/typecheck/TcClassDcl.lhs
index b9711576c4..c20c8aea3b 100644
--- a/compiler/typecheck/TcClassDcl.lhs
+++ b/compiler/typecheck/TcClassDcl.lhs
@@ -48,6 +48,7 @@ import Maybes
 import BasicTypes
 import Bag
 import FastString
+import Util
 
 import Control.Monad
 \end{code}
diff --git a/compiler/typecheck/TcEnv.lhs b/compiler/typecheck/TcEnv.lhs
index 2e870da966..3f5fb09f15 100644
--- a/compiler/typecheck/TcEnv.lhs
+++ b/compiler/typecheck/TcEnv.lhs
@@ -81,6 +81,7 @@ import Outputable
 import Unique
 import FastString
 import ListSetOps
+import Util
 \end{code}
 
 
diff --git a/compiler/typecheck/TcForeign.lhs b/compiler/typecheck/TcForeign.lhs
index e6586d8ff5..90a174081c 100644
--- a/compiler/typecheck/TcForeign.lhs
+++ b/compiler/typecheck/TcForeign.lhs
@@ -48,6 +48,7 @@ import Platform
 import SrcLoc
 import Bag
 import FastString
+import Util
 
 import Control.Monad
 \end{code}
diff --git a/compiler/typecheck/TcGenGenerics.lhs b/compiler/typecheck/TcGenGenerics.lhs
index c4a2c33ba1..89444b2b9e 100644
--- a/compiler/typecheck/TcGenGenerics.lhs
+++ b/compiler/typecheck/TcGenGenerics.lhs
@@ -43,6 +43,7 @@ import Bag
 import Outputable 
 import FastString
 import UniqSupply
+import Util
 
 #include "HsVersions.h"
 \end{code}
diff --git a/compiler/typecheck/TcHsSyn.lhs b/compiler/typecheck/TcHsSyn.lhs
index 9104016938..a026c4381c 100644
--- a/compiler/typecheck/TcHsSyn.lhs
+++ b/compiler/typecheck/TcHsSyn.lhs
@@ -59,6 +59,7 @@ import SrcLoc
 import Bag
 import FastString
 import Outputable
+import Util
 -- import Data.Traversable( traverse )
 \end{code}
 
diff --git a/compiler/typecheck/TcHsType.lhs b/compiler/typecheck/TcHsType.lhs
index a3808822f6..a8837a78f7 100644
--- a/compiler/typecheck/TcHsType.lhs
+++ b/compiler/typecheck/TcHsType.lhs
@@ -73,6 +73,8 @@ import DynFlags ( ExtensionFlag( Opt_DataKinds ) )
 import UniqSupply
 import Outputable
 import FastString
+import Util
+
 import Control.Monad ( unless, when, zipWithM )
 \end{code}
 
diff --git a/compiler/typecheck/TcInteract.lhs b/compiler/typecheck/TcInteract.lhs
index 2a735fe77f..aa7256f707 100644
--- a/compiler/typecheck/TcInteract.lhs
+++ b/compiler/typecheck/TcInteract.lhs
@@ -55,6 +55,7 @@ import Pair ()
 import UniqFM
 import FastString ( sLit ) 
 import DynFlags
+import Util
 \end{code}
 **********************************************************************
 *                                                                    * 
diff --git a/compiler/typecheck/TcRnTypes.lhs b/compiler/typecheck/TcRnTypes.lhs
index d17d3e6a10..23e8973b58 100644
--- a/compiler/typecheck/TcRnTypes.lhs
+++ b/compiler/typecheck/TcRnTypes.lhs
@@ -119,6 +119,7 @@ import DynFlags
 import Outputable
 import ListSetOps
 import FastString
+import Util
 
 import Data.Set (Set)
 
diff --git a/compiler/typecheck/TcSplice.lhs b/compiler/typecheck/TcSplice.lhs
index 86209006d0..7b55ca3b12 100644
--- a/compiler/typecheck/TcSplice.lhs
+++ b/compiler/typecheck/TcSplice.lhs
@@ -66,7 +66,7 @@ import Serialized
 import ErrUtils
 import SrcLoc
 import Outputable
-import Util             ( dropList )
+import Util
 import Data.List        ( mapAccumL )
 import Pair
 import Unique
diff --git a/compiler/types/InstEnv.lhs b/compiler/types/InstEnv.lhs
index e28a3fb53e..21e1acd3e7 100644
--- a/compiler/types/InstEnv.lhs
+++ b/compiler/types/InstEnv.lhs
@@ -32,6 +32,7 @@ import Outputable
 import ErrUtils
 import BasicTypes
 import UniqFM
+import Util
 import Id
 import FastString
 import Data.Data        ( Data, Typeable )
diff --git a/compiler/types/Kind.lhs b/compiler/types/Kind.lhs
index 21e828e99c..bb1b5d7bfa 100644
--- a/compiler/types/Kind.lhs
+++ b/compiler/types/Kind.lhs
@@ -63,6 +63,7 @@ import TyCon
 import VarSet
 import PrelNames
 import Outputable
+import Util
 \end{code}
 
 %************************************************************************
diff --git a/compiler/types/OptCoercion.lhs b/compiler/types/OptCoercion.lhs
index 4880e68a3a..7d707c33c4 100644
--- a/compiler/types/OptCoercion.lhs
+++ b/compiler/types/OptCoercion.lhs
@@ -26,6 +26,7 @@ import Outputable
 import Pair
 import Maybes( allMaybes )
 import FastString
+import Util
 \end{code}
 
 %************************************************************************
diff --git a/compiler/types/TypeRep.lhs b/compiler/types/TypeRep.lhs
index 605c97fcc4..32d4ee2d99 100644
--- a/compiler/types/TypeRep.lhs
+++ b/compiler/types/TypeRep.lhs
@@ -71,6 +71,7 @@ import Outputable
 import FastString
 import Pair
 import StaticFlags( opt_PprStyle_Debug )
+import Util
 
 -- libraries
 import qualified Data.Data        as Data hiding ( TyCon )
diff --git a/compiler/utils/Outputable.lhs b/compiler/utils/Outputable.lhs
index 3130f7175f..9076913751 100644
--- a/compiler/utils/Outputable.lhs
+++ b/compiler/utils/Outputable.lhs
@@ -78,7 +78,7 @@ import FastString
 import FastTypes
 import Platform
 import qualified Pretty
-import Util             ( snocView )
+import Util
 import Pretty           ( Doc, Mode(..) )
 import Panic
 
@@ -936,6 +936,7 @@ pprPanicFastInt heading pretty_msg =
 warnPprTrace :: Bool -> String -> Int -> SDoc -> a -> a
 -- ^ Just warn about an assertion failure, recording the given file and line number.
 -- Should typically be accessed with the WARN macros
+warnPprTrace _     _     _     _    x | not debugIsOn     = x
 warnPprTrace _     _file _line _msg x | opt_NoDebugOutput = x
 warnPprTrace False _file _line _msg x = x
 warnPprTrace True   file  line  msg x
diff --git a/compiler/vectorise/Vectorise/Exp.hs b/compiler/vectorise/Vectorise/Exp.hs
index e75cf0e009..c984c10a24 100644
--- a/compiler/vectorise/Vectorise/Exp.hs
+++ b/compiler/vectorise/Vectorise/Exp.hs
@@ -49,6 +49,7 @@ import Data.Maybe
 import Data.List
 import TcRnMonad (doptM)
 import DynFlags (DynFlag(Opt_AvoidVect))
+import Util
 
 
 -- Main entry point to vectorise expressions -----------------------------------
diff --git a/compiler/vectorise/Vectorise/Monad/InstEnv.hs b/compiler/vectorise/Vectorise/Monad/InstEnv.hs
index 971fd8ff1f..546da3387e 100644
--- a/compiler/vectorise/Vectorise/Monad/InstEnv.hs
+++ b/compiler/vectorise/Vectorise/Monad/InstEnv.hs
@@ -14,6 +14,7 @@ import Class
 import Type
 import TyCon
 import Outputable
+import Util
 
 
 #include "HsVersions.h"
diff --git a/ghc/InteractiveUI.hs b/ghc/InteractiveUI.hs
index 8c1f5ec5ce..7e83565b1a 100644
--- a/ghc/InteractiveUI.hs
+++ b/ghc/InteractiveUI.hs
@@ -50,8 +50,7 @@ import Maybes ( orElse, expectJust )
 import NameSet
 import Panic hiding ( showException )
 import StaticFlags
-import Util ( on, global, toArgs, toCmdArgs, removeSpaces, getCmd,
-              filterOut, seqList, looksLikeModuleName, partitionWith )
+import Util
 
 -- Haskell Libraries
 import System.Console.Haskeline as Haskeline