[GHC] #10907: GHC fails to read file with byte-order mark when LANG=C

[GHC]

#10907: GHC fails to read file with byte-order mark when LANG=C
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              Reporter:              |             Owner:
  RyanGlScott                        |
                  Type:  bug         |            Status:  new
              Priority:  normal      |         Milestone:
             Component:  Compiler    |           Version:  7.10.2
  (Parser)                           |
              Keywords:              |  Operating System:  Linux
          Architecture:  x86_64      |   Type of failure:  GHC doesn't work
  (amd64)                            |  at all
             Test Case:              |        Blocked By:
              Blocking:              |   Related Tickets:  #6016, #6037
Differential Revisions:              |
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 I've attached a minimal example that causes the problem. Compiling
 `ByteOrderMark.hs` like so fails:

 {{{
 $ LANG=C ghc ByteOrderMark.hs
 ByteOrderMark.hs: hLookAhead: invalid argument (invalid byte sequence)
 }}}

 I can reproduce this on x86_64 Linux using GHC 7.10.2 and HEAD.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10907>
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