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optimized profiled version of a program incorectly compiles $!

Here is a test program (file name prgSrc.hs):

import Data.Array.Unboxed

main = do
  let l1 = [1..10] :: [Int]
  let l2 = [ map (i+) l1 | i <- [1..5000000] ]
  let l3 = map (\l -> listArray (1,length l) l) l2 :: [UArray Int Int]
  print $ accumulate l3 0

accumulate [] rv = rv
accumulate (h:t) rv =
  let nextRv = (rv + sum (elems h)) in
  accumulate t $! nextRv

I used ghc 7.0.3-2 on archlinux, 64 bit version. I created it only to check how much memory short unboxed arrays consume. Thanks to the "$!" call at the last line of the "accumulate" function there should not be any stack overflow.

When I compile with these options:[[BR]] ghc --make prgSrc.hs[[BR]] ghc -O2 --make prgSrc.hs[[BR]] ghc -prof -auto-all -caf-all --make prgSrc.hs[[BR]] then there is no problem.

But when I compile with these options:[[BR]] ghc -O2 -prof -auto-all -caf-all --make prgSrc.hs[[BR]] then the program runs out of stack.

This indicates that there is a bug while compiling "$!" in an optimized profiling version of this program.

Trac metadata
Trac field Value
Version 7.0.3
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
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