[GHC] #9752: Output unicode characters on Windows (was: Output unicode characters)

[GHC]

#9752: Output unicode characters on Windows
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              Reporter:  pokiaka     |            Owner:
                  Type:  bug         |           Status:  new
              Priority:  normal      |        Milestone:
             Component:  Compiler    |          Version:  7.8.3
            Resolution:              |         Keywords:  unicode, stderr,
      Operating System:  Windows     |  errors, output, printing, encoding,
       Type of failure:  Incorrect   |  utf, utf8
  result at runtime                  |     Architecture:  Unknown/Multiple
             Test Case:              |       Difficulty:  Easy (less than 1
              Blocking:              |  hour)
Differential Revisions:              |       Blocked By:
                                     |  Related Tickets:
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Changes (by thomie):

 * cc: gintas (added)


Old description:

> When using UnicodeHaskell and having an error with a unicode symbol
> lurking around, GHC fails to print its name.
> So e.g. you get a message of an error "In the first argument of
> (<stderr>: commitBuffer: invalid argument (invalid character)".
>
> I am not certain, but I think that the fix would be to `hSetEncoding
> stderr utf8` before the output is printed. If so, hopefully it should be
> a quick easy fix.
> (And perhaps it would be appropriate to do the same for stdout as-well,
> or just when UnicodeSyntax is on).

New description:

 On Windows, when having an error with a unicode symbol lurking around, GHC
 fails to print its name.
 So e.g. you get a message of an error "In the first argument of (<stderr>:
 commitBuffer: invalid argument (invalid character)".

 I am not certain, but I think that the fix would be to `hSetEncoding
 stderr utf8` before the output is printed. If so, hopefully it should be a
 quick easy fix.
 (And perhaps it would be appropriate to do the same for stdout as-well).

--

Comment:

 Can not reproduce on Linux with GHC 7.8.3, so this seems like a Windows
 only problem.

 By the way: you shouldn't need the UnicodeSyntax extension [1] for above
 example to work/fail.

 [1] https://www.haskell.org/ghc/docs/latest/html/users_guide/syntax-
 extns.html

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9752#comment:3>
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