[GHC] #2410: HEAD build fails when building way=p with WAY_p_OPTS='-prof -caf-all -auto-all'

[GHC]

#2410: HEAD build fails when building way=p with WAY_p_OPTS='-prof -caf-all -auto-
all'
----------------------+-----------------------------------------------------
 Reporter:  pgavin    |          Owner:         
     Type:  bug       |         Status:  new    
 Priority:  normal    |      Milestone:  6.10.1 
Component:  Compiler  |        Version:  6.9    
 Severity:  normal    |     Resolution:         
 Keywords:            |     Difficulty:  Unknown
 Testcase:            |   Architecture:  x86    
       Os:  MacOS X   |  
----------------------+-----------------------------------------------------
Comment (by igloo):

 Testcase:
 {{{
 module C where

 data RealFloat a => Complex a = !a :+ !a
     deriving (Eq, Show)

 instance  (RealFloat a) => Num (Complex a)  where
     {-# SPECIALISE instance Num (Complex Float) #-}
     {-# SPECIALISE instance Num (Complex Double) #-}
     (x :+ y) + (x' :+ y')   =  (x + x') :+ (y + y')
 }}}
 With 6.11.20080927:
 {{{
 $ ghc -prof -caf-all -auto-all -O2 -c C.hs -fforce-recomp
 /tmp/ghc31271_0/ghc31271_0.s: Assembler messages:

 /tmp/ghc31271_0/ghc31271_0.s:14944:0:
      Error: symbol `C_a_CAF_cc_ccs' is already defined

 /tmp/ghc31271_0/ghc31271_0.s:14976:0:
      Error: symbol `C_a_CAF_cc_ccs' is already defined
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2410#comment:3>
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