[GHC] #3437: Optimizer creates space leak on simple code

[GHC]

#3437: Optimizer creates space leak on simple code
-------------------+--------------------------------------------------------
Reporter:  lilac   |          Owner:                
    Type:  bug     |         Status:  new           
Priority:  normal  |      Component:  Compiler      
 Version:  6.10.3  |       Severity:  normal        
Keywords:          |       Testcase:                
      Os:  Linux   |   Architecture:  x86_64 (amd64)
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 The following code should run in constant space:
 {{{
 {-# LANGUAGE BangPatterns #-}
 go (x:xs) !n !k = go xs 0 (n+k+1)
 main = print (go (repeat 'x') 0 0 :: Int)
 }}}
 However, when compiled with -O2, it rapidly eats up the heap. If n and k
 are forced to be Int rather than Integer, the problem disappears.

 Core for the above with -O2 is here:
 http://hpaste.org/fastcgi/hpaste.fcgi/view?id=8268 [[BR]]
 The original code from which this was taken is here:
 http://hpaste.org/fastcgi/hpaste.fcgi/view?id=8266

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3437>
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