diff --git a/data/AlexTemplate.hs b/data/AlexTemplate.hs
index 01f7ac9..3007343 100644
--- a/data/AlexTemplate.hs
+++ b/data/AlexTemplate.hs
@@ -44,18 +44,18 @@ data AlexAddr = AlexA# Addr#
 {-# INLINE alexIndexInt16OffAddr #-}
 alexIndexInt16OffAddr :: AlexAddr -> Int# -> Int#
 alexIndexInt16OffAddr (AlexA# arr) off =
-#ifdef WORDS_BIGENDIAN
-  narrow16Int# i
-  where
-        i    = word2Int# ((high `uncheckedShiftL#` 8#) `or#` low)
-        high = int2Word# (ord# (indexCharOffAddr# arr (off' +# 1#)))
-        low  = int2Word# (ord# (indexCharOffAddr# arr off'))
-        off' = off *# 2#
-#else
 #if __GLASGOW_HASKELL__ >= 901
-  GHC.Exts.int16ToInt#
+  (int16ToInt#
+#endif
+#ifdef WORDS_BIGENDIAN
+  (word16ToInt16# (byteSwap16# (int16ToWord16#
+#endif
+  (indexInt16OffAddr# arr off)
+#ifdef WORDS_BIGENDIAN
+  )))
 #endif
-    (indexInt16OffAddr# arr off)
+#if __GLASGOW_HASKELL__ >= 901
+  )
 #endif
 #else
 alexIndexInt16OffAddr = (Data.Array.!)
@@ -65,22 +65,18 @@ alexIndexInt16OffAddr = (Data.Array.!)
 {-# INLINE alexIndexInt32OffAddr #-}
 alexIndexInt32OffAddr :: AlexAddr -> Int# -> Int#
 alexIndexInt32OffAddr (AlexA# arr) off =
-#ifdef WORDS_BIGENDIAN
-  narrow32Int# i
-  where
-   i    = word2Int# ((b3 `uncheckedShiftL#` 24#) `or#`
-                     (b2 `uncheckedShiftL#` 16#) `or#`
-                     (b1 `uncheckedShiftL#` 8#) `or#` b0)
-   b3   = int2Word# (ord# (indexCharOffAddr# arr (off' +# 3#)))
-   b2   = int2Word# (ord# (indexCharOffAddr# arr (off' +# 2#)))
-   b1   = int2Word# (ord# (indexCharOffAddr# arr (off' +# 1#)))
-   b0   = int2Word# (ord# (indexCharOffAddr# arr off'))
-   off' = off *# 4#
-#else
 #if __GLASGOW_HASKELL__ >= 901
-  GHC.Exts.int32ToInt#
+  (int32ToInt#
+#endif
+#ifdef WORDS_BIGENDIAN
+  (word32ToInt32# (byteSwap32# (int32ToWord32#
+#endif
+  (indexInt32OffAddr# arr off)
+#ifdef WORDS_BIGENDIAN
+  )))
 #endif
-    (indexInt32OffAddr# arr off)
+#if __GLASGOW_HASKELL__ >= 901
+  )
 #endif
 #else
 alexIndexInt32OffAddr = (Data.Array.!)
diff --git a/src/Main.hs b/src/Main.hs
index 493dadf..755d0fa 100644
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -425,7 +425,11 @@ import_glaexts =
       , "indexCharOffAddr#"
       , "indexInt16OffAddr#"
       , "indexInt32OffAddr#"
+      , "int16ToInt#"
+      , "int32ToInt#"
       , "int2Word#"
+      , "int16ToWord16#"
+      , "int32ToWord32#"
       , "narrow16Int#"
       , "narrow32Int#"
       , "negateInt#"
@@ -433,6 +437,10 @@ import_glaexts =
       , "ord#"
       , "uncheckedShiftL#"
       , "word2Int#"
+      , "word16ToInt16#"
+      , "word32ToInt32#"
+      , "byteSwap16#"
+      , "byteSwap32#"
       ]
 
 import_debug :: [String]