[GHC] #4471: Incorrect Unicode output on Windows Console

[GHC]

#4471: Incorrect Unicode output on Windows Console
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    Reporter:  sankeld   |        Owner:                             
        Type:  bug       |       Status:  new                        
    Priority:  normal    |    Milestone:  7.2.1                      
   Component:  Compiler  |      Version:  6.12.3                     
    Keywords:            |     Testcase:                             
   Blockedby:            |   Difficulty:                             
          Os:  Windows   |     Blocking:                             
Architecture:  x86       |      Failure:  Incorrect result at runtime
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Comment(by simonmar):

 There are still too many unknowns here.

  * Won't `_O_U8TEXT` do newline mangling too?  The IO library already does
 that, so we could have a problem.

  * the original report said that piping the output to a file worked fine.
 So presumably we need to do this only when the file descriptor is attached
 to a console?

 And I still don't understand exactly what this `_setmode` is a workaround
 ''for''.  Something apparently goes wrong when you try to output Unicode
 to the console, but at what layer does the problem occur? (GHC.IO, msvcrt,
 Win32, kernel)

 I don't like to be obstructive when there's an apparent fix for a problem,
 but I've seen many cases where a "fix" has introduced new problems, so I
 want to make sure the cure is not worse than the disease :)

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/4471#comment:9>
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