patch applied (packages/base): Replace the implementation of mergesort with a 2x faster one.

[Malcolm Wallace]

Thu Dec 24 07:20:14 PST 2009  Malcolm.Wallace at cs.york.ac.uk
  * Replace the implementation of mergesort with a 2x faster one.
  See ticket http://hackage.haskell.org/trac/ghc/ticket/2143.

    M ./Data/List.hs -4 +44

View patch online:
http://darcs.haskell.org/packages/base/_darcs/patches/20091224152014-6871e-1fd0a48b133e79a9d699449acb2ceafe401118d9.gz