[1] http://www.haskell.org/ghc/ GHC Home Page
[2] http://hackage.haskell.org/trac/ghc GHC Developer's Wiki
- [3] http://www.haskell.org/ghc/docs/latest/html/building/index.html
+ [3] http://hackage.haskell.org/trac/ghc/wiki/Building
Building Guide
[4] http://www.haskell.org/happy/ Happy