Remove code that is dead, as we require __GLASGOW_HASKELL__ >= 504

21 files changed, 43 insertions, 304 deletions

diff --git a/compiler/basicTypes/UniqSupply.lhs b/compiler/basicTypes/UniqSupply.lhs
index 710fc034a6..424dbe2542 100644
--- a/compiler/basicTypes/UniqSupply.lhs
+++ b/compiler/basicTypes/UniqSupply.lhs
@@ -63,11 +63,7 @@ uniqsFromSupply :: UniqSupply -> [Unique]	-- Infinite
 \begin{code}
 mkSplitUniqSupply (C# c#)
   = let
-#if __GLASGOW_HASKELL__ >= 503
 	mask# = (i2w (ord# c#)) `uncheckedShiftL#` (i2w_s 24#)
-#else
-	mask# = (i2w (ord# c#)) `shiftL#` (i2w_s 24#)
-#endif
 	-- here comes THE MAGIC:
 
 	-- This is one of the most hammered bits in the whole compiler
diff --git a/compiler/basicTypes/Unique.lhs b/compiler/basicTypes/Unique.lhs
index 058b0be5d9..a0b28f8375 100644
--- a/compiler/basicTypes/Unique.lhs
+++ b/compiler/basicTypes/Unique.lhs
@@ -120,25 +120,15 @@ i2w_s x = (x::Int#)
 mkUnique (C# c) (I# i)
   = MkUnique (w2i (tag `or#` bits))
   where
-#if __GLASGOW_HASKELL__ >= 503
     tag  = i2w (ord# c) `uncheckedShiftL#` i2w_s 24#
-#else
-    tag  = i2w (ord# c) `shiftL#` i2w_s 24#
-#endif
     bits = i2w i `and#` (i2w 16777215#){-``0x00ffffff''-}
 
 unpkUnique (MkUnique u)
   = let
-	tag = C# (chr# (w2i ((i2w u) `shiftr` (i2w_s 24#))))
+	tag = C# (chr# (w2i ((i2w u) `uncheckedShiftRL#` (i2w_s 24#))))
 	i   = I# (w2i ((i2w u) `and#` (i2w 16777215#){-``0x00ffffff''-}))
     in
     (tag, i)
-  where
-#if __GLASGOW_HASKELL__ >= 503
-    shiftr x y = uncheckedShiftRL# x y
-#else
-    shiftr x y = shiftRL# x y
-#endif
 \end{code}
 
 
diff --git a/compiler/cmm/PprC.hs b/compiler/cmm/PprC.hs
index fa92911340..b8ba5b7cc4 100644
--- a/compiler/cmm/PprC.hs
+++ b/compiler/cmm/PprC.hs
@@ -51,9 +51,7 @@ import PprCmm		() -- instances only
 -- import Debug.Trace
 #endif
 
-#if __GLASGOW_HASKELL__ >= 504
 import Data.Array.ST
-#endif
 import Control.Monad.ST
 
 #if x86_64_TARGET_ARCH
@@ -965,46 +963,20 @@ big_doubles
   | machRepByteWidth F64 == wORD_SIZE      = False
   | otherwise = panic "big_doubles"
 
-#if __GLASGOW_HASKELL__ >= 504
-newFloatArray :: (Int,Int) -> ST s (STUArray s Int Float)
-newFloatArray = newArray_
-
-newDoubleArray :: (Int,Int) -> ST s (STUArray s Int Double)
-newDoubleArray = newArray_
-
 castFloatToIntArray :: STUArray s Int Float -> ST s (STUArray s Int Int)
 castFloatToIntArray = castSTUArray
 
 castDoubleToIntArray :: STUArray s Int Double -> ST s (STUArray s Int Int)
 castDoubleToIntArray = castSTUArray
 
-writeFloatArray :: STUArray s Int Float -> Int -> Float -> ST s ()
-writeFloatArray = writeArray
-
-writeDoubleArray :: STUArray s Int Double -> Int -> Double -> ST s ()
-writeDoubleArray = writeArray
-
-readIntArray :: STUArray s Int Int -> Int -> ST s Int
-readIntArray = readArray
-
-#else
-
-castFloatToIntArray :: MutableByteArray s t -> ST s (MutableByteArray s t)
-castFloatToIntArray = return
-
-castDoubleToIntArray :: MutableByteArray s t -> ST s (MutableByteArray s t)
-castDoubleToIntArray = return
-
-#endif
-
 -- floats are always 1 word
 floatToWord :: Rational -> CmmLit
 floatToWord r
   = runST (do
-	arr <- newFloatArray ((0::Int),0)
-	writeFloatArray arr 0 (fromRational r)
+	arr <- newArray_ ((0::Int),0)
+	writeArray arr 0 (fromRational r)
 	arr' <- castFloatToIntArray arr
-	i <- readIntArray arr' 0
+	i <- readArray arr' 0
 	return (CmmInt (toInteger i) wordRep)
     )
 
@@ -1012,21 +984,21 @@ doubleToWords :: Rational -> [CmmLit]
 doubleToWords r
   | big_doubles				-- doubles are 2 words
   = runST (do
-	arr <- newDoubleArray ((0::Int),1)
-	writeDoubleArray arr 0 (fromRational r)
+	arr <- newArray_ ((0::Int),1)
+	writeArray arr 0 (fromRational r)
 	arr' <- castDoubleToIntArray arr
-	i1 <- readIntArray arr' 0
-	i2 <- readIntArray arr' 1
+	i1 <- readArray arr' 0
+	i2 <- readArray arr' 1
 	return [ CmmInt (toInteger i1) wordRep
 	       , CmmInt (toInteger i2) wordRep
 	       ]
     )
   | otherwise				-- doubles are 1 word
   = runST (do
-	arr <- newDoubleArray ((0::Int),0)
-	writeDoubleArray arr 0 (fromRational r)
+	arr <- newArray_ ((0::Int),0)
+	writeArray arr 0 (fromRational r)
 	arr' <- castDoubleToIntArray arr
-	i <- readIntArray arr' 0
+	i <- readArray arr' 0
 	return [ CmmInt (toInteger i) wordRep ]
     )
 
diff --git a/compiler/ghci/Linker.lhs b/compiler/ghci/Linker.lhs
index 4508e4b2dc..2c1b668e65 100644
--- a/compiler/ghci/Linker.lhs
+++ b/compiler/ghci/Linker.lhs
@@ -68,13 +68,6 @@ import System.Directory
 
 import Control.Exception
 import Data.Maybe
-
-#if __GLASGOW_HASKELL__ >= 503
-import GHC.IOBase	( IO(..) )
-#else
-import PrelIOBase	( IO(..) )
-#endif
-
 \end{code}
 
 
diff --git a/compiler/main/DriverMkDepend.hs b/compiler/main/DriverMkDepend.hs
index af917bd255..b24c14e6b3 100644
--- a/compiler/main/DriverMkDepend.hs
+++ b/compiler/main/DriverMkDepend.hs
@@ -29,9 +29,6 @@ import SrcLoc
 import Data.List
 import CmdLineParser
 
-#if __GLASGOW_HASKELL__ <= 408
-import Panic		( catchJust, ioErrors )
-#endif
 import ErrUtils         ( debugTraceMsg, putMsg )
 
 import Data.IORef	( IORef, readIORef, writeIORef )
diff --git a/compiler/main/StaticFlags.hs b/compiler/main/StaticFlags.hs
index be70daa8bd..2b671594c1 100644
--- a/compiler/main/StaticFlags.hs
+++ b/compiler/main/StaticFlags.hs
@@ -417,13 +417,8 @@ decodeSize str
 -----------------------------------------------------------------------------
 -- RTS Hooks
 
-#if __GLASGOW_HASKELL__ >= 504
 foreign import ccall unsafe "setHeapSize"       setHeapSize       :: Int -> IO ()
 foreign import ccall unsafe "enableTimingStats" enableTimingStats :: IO ()
-#else
-foreign import "setHeapSize"       unsafe setHeapSize       :: Int -> IO ()
-foreign import "enableTimingStats" unsafe enableTimingStats :: IO ()
-#endif
 
 -----------------------------------------------------------------------------
 -- Ways
diff --git a/compiler/nativeGen/MachRegs.lhs b/compiler/nativeGen/MachRegs.lhs
index bffb723d1b..df3be5e4e4 100644
--- a/compiler/nativeGen/MachRegs.lhs
+++ b/compiler/nativeGen/MachRegs.lhs
@@ -96,13 +96,8 @@ import Constants
 import FastTypes
 
 #if powerpc_TARGET_ARCH
-#if __GLASGOW_HASKELL__ >= 504
 import Data.Word	( Word8, Word16, Word32 )
 import Data.Int 	( Int8, Int16, Int32 )
-#else
-import Word     	( Word8, Word16, Word32 )
-import Int 	        ( Int8, Int16, Int32 )
-#endif
 #endif
 
 -- -----------------------------------------------------------------------------
diff --git a/compiler/nativeGen/PprMach.hs b/compiler/nativeGen/PprMach.hs
index 5c731f1b35..1534ec7c96 100644
--- a/compiler/nativeGen/PprMach.hs
+++ b/compiler/nativeGen/PprMach.hs
@@ -2395,41 +2395,11 @@ limitShiftRI x = x
 -- -----------------------------------------------------------------------------
 -- Converting floating-point literals to integrals for printing
 
-#if __GLASGOW_HASKELL__ >= 504
-newFloatArray :: (Int,Int) -> ST s (STUArray s Int Float)
-newFloatArray = newArray_
+castFloatToWord8Array :: STUArray s Int Float -> ST s (STUArray s Int Word8)
+castFloatToWord8Array = castSTUArray
 
-newDoubleArray :: (Int,Int) -> ST s (STUArray s Int Double)
-newDoubleArray = newArray_
-
-castFloatToCharArray :: STUArray s Int Float -> ST s (STUArray s Int Word8)
-castFloatToCharArray = castSTUArray
-
-castDoubleToCharArray :: STUArray s Int Double -> ST s (STUArray s Int Word8)
-castDoubleToCharArray = castSTUArray
-
-writeFloatArray :: STUArray s Int Float -> Int -> Float -> ST s ()
-writeFloatArray = writeArray
-
-writeDoubleArray :: STUArray s Int Double -> Int -> Double -> ST s ()
-writeDoubleArray = writeArray
-
-readCharArray :: STUArray s Int Word8 -> Int -> ST s Char
-readCharArray arr i = do 
-  w <- readArray arr i
-  return $! (chr (fromIntegral w))
-
-#else
-
-castFloatToCharArray :: MutableByteArray s t -> ST s (MutableByteArray s t)
-castFloatToCharArray = return
-
-castDoubleToCharArray :: MutableByteArray s t -> ST s (MutableByteArray s t)
-
-
-castDoubleToCharArray = return
-
-#endif
+castDoubleToWord8Array :: STUArray s Int Double -> ST s (STUArray s Int Word8)
+castDoubleToWord8Array = castSTUArray
 
 -- floatToBytes and doubleToBytes convert to the host's byte
 -- order.  Providing that we're not cross-compiling for a 
@@ -2442,29 +2412,29 @@ castDoubleToCharArray = return
 floatToBytes :: Float -> [Int]
 floatToBytes f
    = runST (do
-        arr <- newFloatArray ((0::Int),3)
-        writeFloatArray arr 0 f
-	arr <- castFloatToCharArray arr
-        i0 <- readCharArray arr 0
-        i1 <- readCharArray arr 1
-        i2 <- readCharArray arr 2
-        i3 <- readCharArray arr 3
-        return (map ord [i0,i1,i2,i3])
+        arr <- newArray_ ((0::Int),3)
+        writeArray arr 0 f
+        arr <- castFloatToWord8Array arr
+        i0 <- readArray arr 0
+        i1 <- readArray arr 1
+        i2 <- readArray arr 2
+        i3 <- readArray arr 3
+        return (map fromIntegral [i0,i1,i2,i3])
      )
 
 doubleToBytes :: Double -> [Int]
 doubleToBytes d
    = runST (do
-        arr <- newDoubleArray ((0::Int),7)
-        writeDoubleArray arr 0 d
-	arr <- castDoubleToCharArray arr
-        i0 <- readCharArray arr 0
-        i1 <- readCharArray arr 1
-        i2 <- readCharArray arr 2
-        i3 <- readCharArray arr 3
-        i4 <- readCharArray arr 4
-        i5 <- readCharArray arr 5
-        i6 <- readCharArray arr 6
-        i7 <- readCharArray arr 7
-        return (map ord [i0,i1,i2,i3,i4,i5,i6,i7])
+        arr <- newArray_ ((0::Int),7)
+        writeArray arr 0 d
+        arr <- castDoubleToWord8Array arr
+        i0 <- readArray arr 0
+        i1 <- readArray arr 1
+        i2 <- readArray arr 2
+        i3 <- readArray arr 3
+        i4 <- readArray arr 4
+        i5 <- readArray arr 5
+        i6 <- readArray arr 6
+        i7 <- readArray arr 7
+        return (map fromIntegral [i0,i1,i2,i3,i4,i5,i6,i7])
      )
diff --git a/compiler/parser/LexCore.hs b/compiler/parser/LexCore.hs
index 7be074a25d..936786d949 100644
--- a/compiler/parser/LexCore.hs
+++ b/compiler/parser/LexCore.hs
@@ -3,7 +3,7 @@ module LexCore where
 import ParserCoreUtils
 import Ratio
 import Char
-import qualified Numeric( readFloat, readDec )
+import Numeric
 
 isNameChar c = isAlpha c || isDigit c || (c == '_') || (c == '\'')
 	       || (c == ':') || (c == '$')
@@ -97,39 +97,3 @@ lexKeyword cont cs =
       ("_",rest) -> cont TKwild rest
       _ -> failP "invalid keyword" ('%':cs) 
 
-
-#if __GLASGOW_HASKELL__ >= 504
--- The readFloat in the Numeric library will do the job
-
-readFloat :: (RealFrac a) => ReadS a
-readFloat = Numeric.readFloat
-
-#else
--- Haskell 98's Numeric.readFloat used to have a bogusly restricted signature
--- so it was incapable of reading a rational.  
--- So for GHCs that have that old bogus library, here is the code, written out longhand.
-
-readFloat r    = [(fromRational ((n%1)*10^^(k-d)),t) | (n,d,s) <- readFix r,
-                                                       (k,t)   <- readExp s] ++
-                 [ (0/0, t) | ("NaN",t)      <- lex r] ++
-                 [ (1/0, t) | ("Infinity",t) <- lex r]
-               where 
-                 readFix r = [(read (ds++ds'), length ds', t)
-                             | (ds,d) <- lexDigits r,
-                               (ds',t) <- lexFrac d ]
-               
-                 lexFrac ('.':ds) = lexDigits ds
-                 lexFrac s        = [("",s)]        
-                 
-                 readExp (e:s) | e `elem` "eE" = readExp' s
-                 readExp s                     = [(0,s)]
-                 
-                 readExp' ('-':s) = [(-k,t) | (k,t) <- Numeric.readDec s]
-                 readExp' ('+':s) = Numeric.readDec s
-                 readExp' s       = Numeric.readDec s
-
-lexDigits :: ReadS String 
-lexDigits s =  case span isDigit s of
-		 (cs,s') | not (null cs) -> [(cs,s')]
-		 otherwise		 -> []
-#endif
diff --git a/compiler/parser/Lexer.x b/compiler/parser/Lexer.x
index 0526b1ec90..d9a0fb08b0 100644
--- a/compiler/parser/Lexer.x
+++ b/compiler/parser/Lexer.x
@@ -379,11 +379,6 @@ $tab+         { warn Opt_WarnTabs (text "Tab character") }
 }
 
 {
--- work around bug in Alex 2.0
-#if __GLASGOW_HASKELL__ < 503
-unsafeAt arr i = arr ! i
-#endif
-
 -- -----------------------------------------------------------------------------
 -- The token type
 
diff --git a/compiler/parser/cutils.c b/compiler/parser/cutils.c
index 08832f298d..4a7b7b3c68 100644
--- a/compiler/parser/cutils.c
+++ b/compiler/parser/cutils.c
@@ -3,19 +3,8 @@ These utility routines are used various
 places in the GHC library.
 */
 
-/* For GHC 4.08, we are relying on the fact that RtsFlags has
- * compatible layout with the current version, because we're
- * #including the current version of RtsFlags.h below.  4.08 didn't
- * ship with its own RtsFlags.h, unfortunately.   For later GHC
- * versions, we #include the correct RtsFlags.h.
- */
-#if __GLASGOW_HASKELL__ < 502
-#include "../includes/Rts.h"
-#include "../includes/RtsFlags.h"
-#else
 #include "Rts.h"
 #include "RtsFlags.h"
-#endif
 
 #include "HsFFI.h"
 
@@ -51,10 +40,7 @@ ghc_memcmp_off( HsAddr a1, HsInt i, HsAddr a2, HsInt len )
 void
 enableTimingStats( void )	/* called from the driver */
 {
-#if __GLASGOW_HASKELL__ >= 411
     RtsFlags.GcFlags.giveStats = ONELINE_GC_STATS;
-#endif
-    /* ignored when bootstrapping with an older GHC */
 }
 
 void
diff --git a/compiler/parser/hschooks.c b/compiler/parser/hschooks.c
index 5c87b3189d..9ccb345db4 100644
--- a/compiler/parser/hschooks.c
+++ b/compiler/parser/hschooks.c
@@ -4,19 +4,8 @@ for various bits of the RTS.  They are linked
 in instead of the defaults.
 */
 
-/* For GHC 4.08, we are relying on the fact that RtsFlags has
- * compatible layout with the current version, because we're
- * #including the current version of RtsFlags.h below.  4.08 didn't
- * ship with its own RtsFlags.h, unfortunately.   For later GHC
- * versions, we #include the correct RtsFlags.h.
- */
-#if __GLASGOW_HASKELL__ < 502
-#include "../includes/Rts.h"
-#include "../includes/RtsFlags.h"
-#else
 #include "Rts.h"
 #include "RtsFlags.h"
-#endif
 
 #include "HsFFI.h"
 
@@ -31,11 +20,8 @@ defaultsHook (void)
 {
     RtsFlags.GcFlags.heapSizeSuggestion = 6*1024*1024 / BLOCK_SIZE;
     RtsFlags.GcFlags.maxStkSize         = 8*1024*1024 / sizeof(W_);
-#if __GLASGOW_HASKELL__ >= 411
-    /* GHC < 4.11 didn't have these */
     RtsFlags.GcFlags.giveStats = COLLECT_GC_STATS;
     RtsFlags.GcFlags.statsFile = stderr;
-#endif
 }
 
 void
diff --git a/compiler/prelude/PrelRules.lhs b/compiler/prelude/PrelRules.lhs
index 386335198c..747817b248 100644
--- a/compiler/prelude/PrelRules.lhs
+++ b/compiler/prelude/PrelRules.lhs
@@ -47,11 +47,7 @@ import StaticFlags      ( opt_SimplExcessPrecision )
 
 import Data.Bits as Bits	( Bits(..), shiftL, shiftR )
 	-- shiftL and shiftR were not always methods of Bits
-#if __GLASGOW_HASKELL__ >= 500
 import Data.Word	( Word )
-#else
-import Data.Word	( Word64 )
-#endif
 \end{code}
 
 
@@ -104,18 +100,14 @@ primOpRules op op_name = primop_rule op
     primop_rule ISrlOp      = two_lits (intShiftOp2 shiftRightLogical)
 
 	-- Word operations
-#if __GLASGOW_HASKELL__ >= 500
     primop_rule WordAddOp   = two_lits (wordOp2    (+))
     primop_rule WordSubOp   = two_lits (wordOp2    (-))
     primop_rule WordMulOp   = two_lits (wordOp2    (*))
-#endif
     primop_rule WordQuotOp  = two_lits (wordOp2Z   quot)
     primop_rule WordRemOp   = two_lits (wordOp2Z   rem)
-#if __GLASGOW_HASKELL__ >= 407
     primop_rule AndOp       = two_lits (wordBitOp2 (.&.))
     primop_rule OrOp        = two_lits (wordBitOp2 (.|.))
     primop_rule XorOp       = two_lits (wordBitOp2 xor)
-#endif
     primop_rule SllOp       = two_lits (wordShiftOp2 Bits.shiftL)
     primop_rule SrlOp       = two_lits (wordShiftOp2 shiftRightLogical)
 
@@ -261,26 +253,18 @@ shiftRightLogical x n = fromIntegral (fromInteger x `shiftR` n :: Word)
 
 
 --------------------------
-#if __GLASGOW_HASKELL__ >= 500
 wordOp2 :: (Integer->Integer->Integer) -> Literal -> Literal -> Maybe CoreExpr
 wordOp2 op (MachWord w1) (MachWord w2)
   = wordResult (w1 `op` w2)
 wordOp2 op l1 l2 = Nothing		-- Could find LitLit
-#endif
 
 wordOp2Z :: (Integer->Integer->Integer) -> Literal -> Literal -> Maybe CoreExpr
 wordOp2Z op (MachWord w1) (MachWord w2)
   | w2 /= 0 = wordResult (w1 `op` w2)
 wordOp2Z op l1 l2 = Nothing	-- LitLit or zero dividend
 
-#if __GLASGOW_HASKELL__ >= 500
 wordBitOp2 op l1@(MachWord w1) l2@(MachWord w2)
   = wordResult (w1 `op` w2)
-#else
--- Integer is not an instance of Bits, so we operate on Word64
-wordBitOp2 op l1@(MachWord w1) l2@(MachWord w2)
-  = wordResult ((fromIntegral::Word64->Integer) (fromIntegral w1 `op` fromIntegral w2))
-#endif
 wordBitOp2 op l1 l2 = Nothing		-- Could find LitLit
 
 wordShiftOp2 :: (Integer->Int->Integer) -> Literal -> Literal -> Maybe CoreExpr
@@ -360,11 +344,9 @@ intResult :: Integer -> Maybe CoreExpr
 intResult result
   = Just (mkIntVal (toInteger (fromInteger result :: Int)))
 
-#if __GLASGOW_HASKELL__ >= 500
 wordResult :: Integer -> Maybe CoreExpr
 wordResult result
   = Just (mkWordVal (toInteger (fromInteger result :: Word)))
-#endif
 \end{code}
 
 
diff --git a/compiler/simplCore/SimplMonad.lhs b/compiler/simplCore/SimplMonad.lhs
index 5b6ac4001a..a198b32cce 100644
--- a/compiler/simplCore/SimplMonad.lhs
+++ b/compiler/simplCore/SimplMonad.lhs
@@ -43,11 +43,7 @@ import FastTypes
 
 import GHC.Exts		( indexArray# )
 
-#if __GLASGOW_HASKELL__ < 503
-import PrelArr  ( Array(..) )
-#else
 import GHC.Arr  ( Array(..) )
-#endif
 
 import Array		( array, (//) )
 
diff --git a/compiler/utils/Binary.hs b/compiler/utils/Binary.hs
index e479b791da..6bce8321fa 100644
--- a/compiler/utils/Binary.hs
+++ b/compiler/utils/Binary.hs
@@ -202,12 +202,6 @@ writeBinMem (BinMem _ ix_r sz_r arr_r) fn = do
   arr <- readIORef arr_r
   ix  <- readFastMutInt ix_r
   hPutArray h arr ix
-#if __GLASGOW_HASKELL__ <= 500
-  -- workaround a bug in old implementation of hPutBuf (it doesn't
-  -- set the FILEOBJ_RW_WRITTEN flag on the file object, so the file doens't
-  -- get flushed properly).  Adding an extra '\0' doens't do any harm.
-  hPutChar h '\0'
-#endif
   hClose h
 
 readBinMem :: FilePath -> IO BinHandle
@@ -272,11 +266,7 @@ getWord8 (BinMem _ ix_r sz_r arr_r) = do
     ix <- readFastMutInt ix_r
     sz <- readFastMutInt sz_r
     when (ix >= sz)  $
-#if __GLASGOW_HASKELL__ <= 408
-	throw (mkIOError eofErrorType "Data.Binary.getWord8" Nothing Nothing)
-#else
 	ioError (mkIOError eofErrorType "Data.Binary.getWord8" Nothing Nothing)
-#endif
     arr <- readIORef arr_r
     w <- unsafeRead arr ix
     writeFastMutInt ix_r (ix+1)
@@ -516,23 +506,12 @@ freezeByteArray arr = IO $ \s ->
   (# s, BA arr #) }
 
 writeByteArray :: MutableByteArray# RealWorld -> Int# -> Word8 -> IO ()
-
-#if __GLASGOW_HASKELL__ < 503
-writeByteArray arr i w8 = IO $ \s ->
-  case word8ToWord w8 of { W# w# -> 
-  case writeCharArray# arr i (chr# (word2Int# w#)) s  of { s ->
-  (# s , () #) }}
-#else
 writeByteArray arr i (W8# w) = IO $ \s ->
   case writeWord8Array# arr i w s of { s ->
   (# s, () #) }
-#endif
 
-#if __GLASGOW_HASKELL__ < 503
-indexByteArray a# n# = fromIntegral (I# (ord# (indexCharArray# a# n#)))
-#else
+indexByteArray :: ByteArray# -> Int# -> Word8
 indexByteArray a# n# = W8# (indexWord8Array# a# n#)
-#endif
 
 instance (Integral a, Binary a) => Binary (Ratio a) where
     put_ bh (a :% b) = do put_ bh a; put_ bh b
diff --git a/compiler/utils/Digraph.lhs b/compiler/utils/Digraph.lhs
index 669f718b43..9129d9d929 100644
--- a/compiler/utils/Digraph.lhs
+++ b/compiler/utils/Digraph.lhs
@@ -252,27 +252,16 @@ draw (Node x ts) = grp this (space (length this)) (stLoop ts)
 %************************************************************************
 
 \begin{code}
-#if __GLASGOW_HASKELL__ >= 504
-newSTArray :: Ix i => (i,i) -> e -> ST s (STArray s i e)
-newSTArray = newArray
-
-readSTArray :: Ix i => STArray s i e -> i -> ST s e
-readSTArray = readArray
-
-writeSTArray :: Ix i => STArray s i e -> i -> e -> ST s ()
-writeSTArray = writeArray
-#endif
-
 type Set s    = STArray s Vertex Bool
 
 mkEmpty      :: Bounds -> ST s (Set s)
-mkEmpty bnds  = newSTArray bnds False
+mkEmpty bnds  = newArray bnds False
 
 contains     :: Set s -> Vertex -> ST s Bool
-contains m v  = readSTArray m v
+contains m v  = readArray m v
 
 include      :: Set s -> Vertex -> ST s ()
-include m v   = writeSTArray m v True
+include m v   = writeArray m v True
 \end{code}
 
 \begin{code}
diff --git a/compiler/utils/FastMutInt.lhs b/compiler/utils/FastMutInt.lhs
index 86ca0bd7f7..3c2a199198 100644
--- a/compiler/utils/FastMutInt.lhs
+++ b/compiler/utils/FastMutInt.lhs
@@ -19,10 +19,6 @@ module FastMutInt(
 
 import GHC.Base
 import GHC.IOBase
-
-#if __GLASGOW_HASKELL__ < 411
-newByteArray# = newCharArray#
-#endif
 \end{code}
 
 \begin{code}
diff --git a/compiler/utils/Panic.lhs b/compiler/utils/Panic.lhs
index eb3ce78dd3..53d75b05a9 100644
--- a/compiler/utils/Panic.lhs
+++ b/compiler/utils/Panic.lhs
@@ -39,7 +39,7 @@ import Posix		( Handler(Catch), installHandler, sigINT, sigQUIT )
 import GHC.ConsoleHandler
 #endif
 
-import Control.Exception hiding (try)
+import Control.Exception
 import Control.Concurrent ( myThreadId, MVar, ThreadId, withMVar, newMVar )
 import Data.Dynamic
 import qualified Control.Exception as Exception
@@ -171,33 +171,14 @@ tryMost action = do r <- try action; filter r
 tryUser :: IO a -> IO (Either Exception.Exception a)
 tryUser action = tryJust tc_errors action
   where 
-#if __GLASGOW_HASKELL__ > 504 || __GLASGOW_HASKELL__ < 500
+#if __GLASGOW_HASKELL__ > 504
 	tc_errors e@(Exception.IOException ioe) | isUserError ioe = Just e
-#elif __GLASGOW_HASKELL__ == 502
-	tc_errors e@(UserError _) = Just e
 #else 
 	tc_errors e@(Exception.IOException ioe) | isUserError e = Just e
 #endif
 	tc_errors _other = Nothing
 \end{code}	
 
-Compatibility stuff:
-
-\begin{code}
-#if __GLASGOW_HASKELL__ <= 408
-try = Exception.tryAllIO
-#else
-try = Exception.try
-#endif
-
-#if __GLASGOW_HASKELL__ <= 408
-catchJust = Exception.catchIO
-tryJust   = Exception.tryIO
-ioErrors  = Exception.justIoErrors
-throwTo   = Exception.raiseInThread
-#endif
-\end{code}
-
 Standard signal handlers for catching ^C, which just throw an
 exception in the target thread.  The current target thread is
 the thread at the head of the list in the MVar passed to
diff --git a/compiler/utils/Pretty.lhs b/compiler/utils/Pretty.lhs
index 0fc817f288..f611d7a13c 100644
--- a/compiler/utils/Pretty.lhs
+++ b/compiler/utils/Pretty.lhs
@@ -1022,11 +1022,7 @@ printDoc mode hdl doc
   -- some versions of hPutBuf will barf if the length is zero
 hPutLitString handle a# 0# = return ()
 hPutLitString handle a# l#
-#if __GLASGOW_HASKELL__ < 411
-  = hPutBuf handle (A# a#) (I# l#)
-#else
   = hPutBuf handle (Ptr a#) (I# l#)
-#endif
 
 -- Printing output in LeftMode is performance critical: it's used when
 -- dumping C and assembly output, so we allow ourselves a few dirty
@@ -1066,9 +1062,4 @@ layLeft b (TextBeside s sl p) 	= put b s >> layLeft b p
     put b (Str s)    = bPutStr  b s
     put b (PStr s)   = bPutFS   b s
     put b (LStr s l) = bPutLitString b s l
-
-#if __GLASGOW_HASKELL__ < 503
-hPutBuf = hPutBufFull
-#endif
-
 \end{code}
diff --git a/compiler/utils/UniqFM.lhs b/compiler/utils/UniqFM.lhs
index 267aeabd81..bb5b33e8bc 100644
--- a/compiler/utils/UniqFM.lhs
+++ b/compiler/utils/UniqFM.lhs
@@ -827,18 +827,8 @@ shiftR_ :: FastInt -> FastInt -> FastInt
 #if __GLASGOW_HASKELL__
 {-# INLINE shiftL_ #-}
 {-# INLINE shiftR_ #-}
-#if __GLASGOW_HASKELL__ >= 503
 shiftL_ n p = word2Int#((int2Word# n) `uncheckedShiftL#` p)
-#else
-shiftL_ n p = word2Int#((int2Word# n) `shiftL#` p)
-#endif
-shiftR_ n p = word2Int#((int2Word# n) `shiftr` p)
-  where
-#if __GLASGOW_HASKELL__ >= 503
-    shiftr x y = uncheckedShiftRL# x y
-#else
-    shiftr x y = shiftRL# x y
-#endif
+shiftR_ n p = word2Int#((int2Word# n) `uncheckedShiftRL#` p)
 
 #else /* not GHC */
 shiftL_ n p = n * (2 ^ p)
diff --git a/compiler/utils/Util.lhs b/compiler/utils/Util.lhs
index 6463c1ac42..39fd64b679 100644
--- a/compiler/utils/Util.lhs
+++ b/compiler/utils/Util.lhs
@@ -890,13 +890,9 @@ handleDyn :: Typeable ex => (ex -> IO a) -> IO a -> IO a
 handleDyn = flip catchDyn
 
 handle :: (Exception -> IO a) -> IO a -> IO a
-#if __GLASGOW_HASKELL__ < 501
-handle = flip Exception.catchAllIO
-#else
 handle h f = f `Exception.catch` \e -> case e of
     ExitException _ -> throw e
     _               -> h e
-#endif
 
 -- --------------------------------------------------------------
 -- check existence & modification time at the same time