[GHC] #5915: Code using seq has wrong strictness when unoptimised (too strict)

[GHC]

#5915: Code using seq has wrong strictness when unoptimised (too strict)
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 Reporter:  michal.palka                 |          Owner:                            
     Type:  bug                          |         Status:  new                       
 Priority:  normal                       |      Component:  Compiler                  
  Version:  7.3                          |       Keywords:  seq strictness strict lazy
       Os:  Unknown/Multiple             |   Architecture:  Unknown/Multiple          
  Failure:  Incorrect result at runtime  |       Testcase:                            
Blockedby:                               |       Blocking:                            
  Related:                               |  
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 The following piece of code gets miscompiled if no optimisation is used.
 The program crashes instead of printing `[0]`, which would be the correct
 behaviour. GHC 7.3.20111127 has been used for triggering this bug.

 {{{
 test = seq (seq id (\a -> undefined a))

 main = do
   print $ test [0]
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/5915>
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