[project @ 2006-01-10 14:39:38 by simonmar]

prevChar: don't back up over decoding errors

diff --git a/ghc/compiler/utils/Encoding.hs b/ghc/compiler/utils/Encoding.hs
index 7b35e65..152bf3c 100644 (file)
--- a/ghc/compiler/utils/Encoding.hs
+++ b/ghc/compiler/utils/Encoding.hs
@@ -105,7 +105,7 @@ utf8PrevChar p = utf8CharStart (p `plusPtr` (-1))
 utf8CharStart :: Ptr Word8 -> IO (Ptr Word8)
 utf8CharStart p = go p
  where go p = do w <- peek p
-                if (w .&. 0xC0) == 0x80
+                if w >= 0x80 && w < 0xC0
                        then go (p `plusPtr` (-1))
                        else return p