[GHC] #11050: [bug] ModOrigin: hidden module redefined

[GHC]

#11050: [bug] ModOrigin: hidden module redefined
-------------------------------------+-------------------------------------
        Reporter:  codeonwort        |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.0.1
       Component:  Compiler          |              Version:  7.10.2
      Resolution:                    |             Keywords:
Operating System:  Linux             |         Architecture:  x86_64
 Type of failure:  Compile-time      |  (amd64)
  crash                              |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Changes (by thomie):

 * milestone:  7.10.3 => 8.0.1


Comment:

 To reproduce on Ubuntu with ghc-7.10.2:

 * Install the `haste-compiler` Debian package from http://haste-
 lang.org/downloads/

 * Create `T11050.hs`:
 {{{
 import Haste.DOM
 main = do
    addChild undefined undefined
    return ()
 }}}

 * Run
 {{{
 $ ghc -no-user-package-db -package-db=/usr/lib/haste-compiler/x86_64
 -linux-haste-0.5.2-ghc-7.10.2/package.conf.d T11050.hs -fforce-recomp
 }}}

 Somehow, `haste` managed to create a package (`haste-lib`) that lists all
 hidden modules twice:
 {{{
 $ ghc-pkg --package-db=/usr/lib/haste-compiler/x86_64-linux-
 haste-0.5.2-ghc-7.10.2/package.conf.d describe haste-lib
 ...
 hidden-modules: Haste.App.Client Haste.App.Monad Haste.App.Protocol
                 Haste.Audio.Events Haste.Binary.Get Haste.Binary.Put
                 Haste.Binary.Types Haste.Compiler.Flags
 Haste.Concurrent.Monad
                 Haste.Concurrent.Ajax Haste.DOM.Core
 Haste.Events.BasicEvents
                 Haste.Events.Core Haste.Events.KeyEvents
 Haste.Events.MouseEvents
                 Haste.Events.TouchEvents Haste.Hash Haste.Random
 Haste.Timer

                 Haste.App.Client Haste.App.Monad Haste.App.Protocol
                 Haste.Audio.Events Haste.Binary.Get Haste.Binary.Put
                 Haste.Binary.Types Haste.Compiler.Flags
 Haste.Concurrent.Monad
                 Haste.Concurrent.Ajax Haste.DOM.Core
 Haste.Events.BasicEvents
                 Haste.Events.Core Haste.Events.KeyEvents
 Haste.Events.MouseEvents
                 Haste.Events.TouchEvents Haste.Hash Haste.Random
 Haste.Timer
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11050#comment:1>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler