[GHC] #1171: GHC generates incorrect code with -O for Haskell 98 program

[GHC]

#1171: GHC generates incorrect code with -O for Haskell 98 program
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 Reporter:  neil      |          Owner:          
     Type:  bug       |         Status:  closed  
 Priority:  normal    |      Milestone:  6.6.1   
Component:  Compiler  |        Version:  6.6     
 Severity:  major     |     Resolution:  invalid 
 Keywords:            |     Difficulty:  Unknown 
 Testcase:  cg059     |   Architecture:  Multiple
       Os:  Multiple  |  
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Comment (by Stefan O'Rear <stefanor at cox.net>):

 Such behavior would probably be excusable, indeed desirable in a Haskell
 98 compiler.  But GHC is not just a Haskell 98 compiler - it also claims
 to follow the document "A Semantics for Imprecise Exceptions".  And that
 document, if I recall correctly, does not specify a single _|_ but rather
 allows expressions to evaluate to a set of expressions, and changing the
 set of expressions returned is not a semantically correct compiler.  Does
 yhc use Control.Exception.catch?  If so, I would call this behavior
 Incorrect.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1171>
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