[GHC] #7161: hSetNewlineMode and hSetEncoding can be performed on closed and semi-closed handles

[GHC]

#7161: hSetNewlineMode and hSetEncoding can be performed on closed and semi-closed
handles
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        Reporter:  duncan            |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Core Libraries    |              Version:  7.6.1-rc1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by joeyhess):

 I reproduced this bug in the wild today. Here is my test case:

 import GHC.IO.Encoding
 import System.IO

 main = do
         e <- getFileSystemEncoding
         hClose stdin
         hSetEncoding stdin e

 ghc 8.0.1 on Linux.

 For me, the crash only occurs with LANG=C. With my usual locale of
 en_US.utf8 there is no crash. Perhaps this is why there was a problem
 reproducing it.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7161#comment:10>
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