patch applied (ghc): Robustify the setting of implied flags

[Simon Peyton Jones]

Wed Sep 10 01:15:28 PDT 2008  simonpj at microsoft.com
  * Robustify the setting of implied flags
  
  When setting implied flags, do so recursively.  So if -Xa implies -Xb,
  and -Xb implies -Xc, we do the right thing. 
  
  I thought we needed this, but we don't.  But it seems like a good idea
  anyway.
  

    M ./compiler/main/DynFlags.hs -9 +13

View patch online:
http://darcs.haskell.org/ghc/_darcs/patches/20080910081528-1287e-6432b94d59711d6278d181903a5888903f17252e.gz