[GHC] #1001: Failed to load interface for `IO'

[GHC]

#1001: Failed to load interface for `IO'
-------------------------------------------+--------------------------------
    Reporter:  benjamin.franksen at bessy.de  |       Owner:         
        Type:  bug                         |      Status:  new    
    Priority:  normal                      |   Milestone:         
   Component:  Compiler                    |     Version:  6.6    
    Severity:  normal                      |    Keywords:         
  Difficulty:  Unknown                     |    Testcase:         
Architecture:  Unknown                     |          Os:  Unknown
-------------------------------------------+--------------------------------
I was trying to compile John Macheam's "GetOptions" with ghc-6.6. It
 failed saying


 {{{
 ben at sarun: .../repos/GetOptions > runhaskell Setup.hs build
 Preprocessing library GetOptions-1.0...
 Building GetOptions-1.0...

 GetOptions.hs:31:7:
     Could not find module `IO':
       it is a member of package haskell98, which is hidden
 }}}

 I exposed haskell98:

 {{{
 ben at sarun: .../repos/GetOptions > sudo ghc-pkg expose haskell98
 Saving old package config file... done.
 Writing new package config file... done.
 }}}

 But still no luck... Anyway then I said to myself "forget it, just use the
 hierarchical library stuff", hid haskell98 package again, and changed the
 import stuff a bit (see below). Result:

 {{{
 ben at sarun: .../repos/GetOptions > runhaskell Setup.hs build

 <interactive>:1:84:
     Failed to load interface for `IO':
       it is a member of package haskell98, which is hidden
 ghc-6.6: panic! (the 'impossible' happened)
   (GHC version 6.6 for x86_64-unknown-linux):
         interactiveUI:flush

 Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug
 }}}

 This is the "fix" I applied:

 {{{
 ben at sarun: .../repos/GetOptions > darcs whatsnew
 {
 hunk ./GetOptions.hs 27
 -import List
 +import Data.List
 hunk ./GetOptions.hs 30
 -import System
 -import IO
 +import System.IO
 +--import IO
 }
 }}}

 Here is the repo I pulled from, so maybe you can reproduce the bug:

 {{{
 ben at sarun: .../repos/GetOptions > cat _darcs/prefs/defaultrepo
 http://repetae.net/john/repos/GetOptions
 }}}

 I could be that my ghc installation is completely screwed up but I
 wouldn't know how or why.

 Ben

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1001>
GHC <http://www.haskell.org/ghc/>
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