[GHC] #3813: Invalid warning from GHCi

[GHC]

#3813: Invalid warning from GHCi
---------------------------------+------------------------------------------
    Reporter:  NeilMitchell      |       Owner:                                   
        Type:  bug               |      Status:  new                              
    Priority:  normal            |   Component:  GHCi                             
     Version:  6.10.4            |    Keywords:                                   
          Os:  Unknown/Multiple  |    Testcase:                                   
Architecture:  Unknown/Multiple  |     Failure:  Incorrect warning at compile-time
---------------------------------+------------------------------------------
 {{{
 C:\Neil>ghci -Wall
 GHCi, version 6.10.3.20090530: http://www.haskell.org/ghc/  :? for help
 Loading package ghc-prim ... linking ... done.
 Loading package integer ... linking ... done.
 Loading package base ... linking ... done.
 Prelude> x <- return True

 <interactive>:1:0: Warning: Defined but not used: `x'
 Prelude> x
 True
 Prelude>
 }}}

 This error comes up in practice when writing .ghci files, for example for
 HLint. The user who reported it to me was running GHC 6.12.1.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3813>
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