[GHC] #6156: Optimiser bug on linux-powerpc

[GHC]

#6156: Optimiser bug on linux-powerpc
------------------------------------------+---------------------------------
  Reporter:  erikd                        |          Owner:  igloo  
      Type:  bug                          |         Status:  new    
  Priority:  normal                       |      Milestone:  7.6.1  
 Component:  Compiler                     |        Version:  7.4.1  
Resolution:                               |       Keywords:         
        Os:  Linux                        |   Architecture:  powerpc
   Failure:  Incorrect result at runtime  |     Difficulty:  Unknown
  Testcase:                               |      Blockedby:         
  Blocking:                               |        Related:         
------------------------------------------+---------------------------------

Comment(by erikd):

 Similar to the case of `succ` in the previous comment `pred` also
 misbehaves. This:

 {{{
 putStrLn (showHex (pred (0xa1a2a3a500000000 :: Word64)) "")
 }}}

 results in:

 {{{
 Enum.pred{Word64}: tried to take `pred' of minBound
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/6156#comment:32>
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