[GHC] #15336: ./System/IO.hs accidentally overridden when running ghci

[GHC]

#15336: ./System/IO.hs accidentally overridden when running ghci
-------------------------------------+-------------------------------------
           Reporter:  luqui          |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:  8.6.1
          Component:  GHCi           |           Version:  8.2.2
           Keywords:                 |  Operating System:  MacOS X
       Architecture:                 |   Type of failure:  GHC rejects
  Unknown/Multiple                   |  valid program
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 Running ghci fails if there is a System/IO.hs module present in the
 current directory.  Doesn't seem like desirable behavior.

 {{{
 % mkdir System
 % touch System/IO.hs
 % ghci
 GHCi, version 8.2.2: http://www.haskell.org/ghc/  :? for help

 <interactive>:1:19: error:
     Not in scope: ‘System.IO.hSetBuffering’
     No module named ‘System.IO’ is imported.

 <interactive>:1:43: error:
     Not in scope: ‘System.IO.stdin’
     No module named ‘System.IO’ is imported.

 <interactive>:1:60: error:
     Not in scope: data constructor ‘System.IO.NoBuffering’
     No module named ‘System.IO’ is imported.

 <interactive>:1:99: error:
     Not in scope: ‘System.IO.hSetBuffering’
     No module named ‘System.IO’ is imported.

 <interactive>:1:123: error:
     Not in scope: ‘System.IO.stdout’
     No module named ‘System.IO’ is imported.

 <interactive>:1:140: error:
     Not in scope: data constructor ‘System.IO.NoBuffering’
     No module named ‘System.IO’ is imported.

 <interactive>:1:179: error:
     Not in scope: ‘System.IO.hSetBuffering’
     No module named ‘System.IO’ is imported.

 <interactive>:1:203: error:
     Not in scope: ‘System.IO.stderr’
     No module named ‘System.IO’ is imported.

 <interactive>:1:220: error:
     Not in scope: data constructor ‘System.IO.NoBuffering’
     No module named ‘System.IO’ is imported.
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15336>
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