[GHC] #2456: Generics compilation problem: "FATAL:Symbol _XJv_srt already defined."

[GHC]

#2456: Generics compilation problem: "FATAL:Symbol _XJv_srt already defined."
----------------------+-----------------------------------------------------
 Reporter:  ronwalf   |          Owner:          
     Type:  bug       |         Status:  reopened
 Priority:  normal    |      Milestone:          
Component:  Compiler  |        Version:  6.9     
 Severity:  normal    |     Resolution:          
 Keywords:            |     Difficulty:  Unknown 
 Testcase:            |   Architecture:  x86     
       Os:  MacOS X   |  
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Changes (by simonpj):

  * difficulty:  => Unknown

Comment:

 Excellent point.  That is bad. I'll fix.

 Meanwhile, in both cases you have
 {{{
 deriving instance Data (Expr Const)
 deriving instance Data (Expr Var)
 }}}
 Question: do you really want this?  You're generating more or less the
 same code twice.  Why not write this?
 {{{
 deriving instance Data a => Data (Expr a)
 }}}

 Simon

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2456#comment:4>
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