[GHC] #6104: Regression: space leak in HEAD vs. 7.4

[GHC]

#6104: Regression: space leak in HEAD vs. 7.4
---------------------------------+------------------------------------------
    Reporter:  simonmar          |       Owner:  simonpj                     
        Type:  bug               |      Status:  new                         
    Priority:  highest           |   Milestone:  7.6.1                       
   Component:  Compiler          |     Version:  7.5                         
    Keywords:                    |          Os:  Unknown/Multiple            
Architecture:  Unknown/Multiple  |     Failure:  Compile-time performance bug
  Difficulty:  Unknown           |    Testcase:                              
   Blockedby:                    |    Blocking:                              
     Related:                    |  
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Comment(by simonpj):

 There doesn't seem to be much of a difference on `CopyFile`, at least not
 now. Here's the size of the .o file:
 {{{
                 text       data     bss     dec     hex filename
 With 7.4.1      6480        760       0    7240    1c48 T6104.o
 With HEAD       4769        704       0    5473    1561 T6104.o
 }}}
 So HEAD generates less code, not more.  The compiler does allocate a bit
 more, but not much:
 {{{
 -------- 7.4.1  with -O on CopyFile.hs ------------
 [1 of 1] Compiling CopyFile         ( T6104.hs, T6104.o )
      146,131,584 bytes allocated in the heap
       67,295,032 bytes copied during GC
       16,663,568 bytes maximum residency (6 sample(s))
        1,330,480 bytes maximum slop
               33 MB total memory in use (0 MB lost due to fragmentation)


 -------- HEAD  with -O on CopyFile.hs ------------
 [1 of 1] Compiling CopyFile         ( T6104.hs, T6104.o )
      156,295,232 bytes allocated in the heap
       71,474,496 bytes copied during GC
       16,357,872 bytes maximum residency (7 sample(s))
        1,451,648 bytes maximum slop
               32 MB total memory in use (0 MB lost due to fragmentation)
 }}}
 I suppose the next thing is to try compiling Cabal.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/6104#comment:8>
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