id,summary,reporter,owner,description,type,status,priority,milestone,component,version,resolution,keywords,cc,os,architecture,failure,difficulty,testcase,blockedby,blocking,related
2080,Bug in CmmOpt,simonmar,igloo,"Two bugs are demonstrated by the following code.  The first one is wrong code generated for the comparison, and the second is the panic (see the comment):

{{{
module Test where
import GHC.Base

utf8DecodeChar# :: Addr# -> Bool -> Bool
{-# NOINLINE utf8DecodeChar# #-}
utf8DecodeChar# a# fred =
  case () of 
    _ | word2Int# (indexWord8OffAddr# a# 0#) <=# 0x7F# -> True

-- Omitting the next line gives an ASSERT error:
-- ghc-6.9: panic! (the 'impossible' happened)
--   (GHC version 6.9 for x86_64-unknown-linux):
-- 	ASSERT failed! file nativeGen/MachCodeGen.hs line 1049
-- %MO_S_Le_I8(I8[R2], 127 :: I8)
      | fred -> True

      | otherwise -> False
}}}
",merge,closed,normal,6.8.3,Compiler,6.8.2,fixed,,,Unknown/Multiple,Unknown/Multiple,,Unknown,,,,