[GHC] #3840: ghc-6.12.1 takes longer to compile code and produces bigger binaries compared to ghc-6.10.4

[GHC]

#3840: ghc-6.12.1 takes longer to compile code and produces bigger binaries
compared to ghc-6.10.4
-------------------------+--------------------------------------------------
    Reporter:  maeder    |        Owner:              
        Type:  bug       |       Status:  new         
    Priority:  normal    |    Milestone:  6.12.2      
   Component:  Compiler  |      Version:  6.12.1      
    Keywords:            |   Difficulty:              
          Os:  Linux     |     Testcase:              
Architecture:  x86       |      Failure:  None/Unknown
-------------------------+--------------------------------------------------

Comment(by maeder):

 I've attached a small subset of our sources that hopefully illustrate the
 problem.

 {{{
 tar zxvf Hets.tgz
 cd Hets
 ghc --make -O -iatermlib/src Common/atc.hs

 ls -S1sh */*.o */*/*.o */*/*/*.o
 rm */*.o */*/*.o */*/*/*.o
 }}}

 The only packages required to compile are base, containers, array, old-
 time, time and ghc-prim.
 It'll compile 15 files. The generated instances are in the file
 ATC/AS_Annotation.hs. The size of the file ATC/AS_Annotation.o is:

 {{{
 ghc-6.10.4: 116K
 ghc-6.12.1: 528K
 ghc-6.13.20100211: 196K
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3840#comment:13>
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