[GHC] #7150: unjustified overlapping instances error

[GHC]

#7150: unjustified overlapping instances error
-------------------------+--------------------------------------------------
    Reporter:  maeder    |       Owner:                           
        Type:  bug       |      Status:  new                      
    Priority:  highest   |   Milestone:  7.6.1                    
   Component:  Compiler  |     Version:  7.6.1-rc1                
    Keywords:            |          Os:  Solaris                  
Architecture:  x86       |     Failure:  GHC rejects valid program
  Difficulty:  Unknown   |    Testcase:                           
   Blockedby:            |    Blocking:                           
     Related:            |  
-------------------------+--------------------------------------------------

Comment(by simonpj):

 OK I set HC and HCPKG, typed 'make' and ended up with
 {{{
 make
 ghc-pkg: cannot find package HaXml
 ghc-pkg: cannot find package HaXml
 ghc-pkg: cannot find package tar
 ghc-pkg: cannot find package glade
 ghc-pkg: cannot find package hexpat
 ghc-pkg: cannot find package HTTP
 ghc-pkg: cannot find package uni-uDrawGraph
 ghc-pkg: cannot find package warp
 ghc-pkg: cannot find package wai-extra
 ghc-pkg: cannot find package parsec1
 /home/simonpj/5builds/HEAD/inplace/bin/ghc-stage2 -optl-s
 -XTemplateHaskell -threaded -rtsopts --make -o hets hets.hs -fcontext-
 stack=26    -DNOHTTP -DUNIX        -DRDFLOGIC -DCASLEXTENSIONS  -Wall
 -fwarn-tabs -fwarn-unrecognised-pragmas -fno-warn-orphans -fno-warn-
 unused-do-bind

 OMDoc/Import.hs:87:8:
     Could not find module `Network.URI'
     Use -v to see a list of the files searched for.
 make: *** [hets] Error 1
 }}}
 So are you saying that I first need to manually install (some of) the
 packages you listed?  And modify some of them (you mentioned patching)?

 I'm willing to follow instructions.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7150#comment:6>
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