The Glasgow Haskell Compiler
============================

This is the source tree for [GHC] [1], a compiler and interactive
environment for the Haskell functional programming language.

For more information, visit [GHC's web site] [1].

Information for developers of GHC can be found on the [GHC Trac] [2].


Getting the Source
==================

There are two ways to get a source tree:

 1. *Download source tarballs*

  Download the GHC source distribution:

        ghc-<version>-src.tar.bz2

  which contains GHC itself and the "boot" libraries.

 2. *Check out the source code from git*

  First clone the GHC github read-only repository:

        $ git clone git://github.com/ghc/ghc.git

  Then run the `sync-all` script in that repository to get the other repositories:

        $ cd ghc
        $ ./sync-all get

  This checks out the "boot" packages.

  **DO NOT submit pull request directly to the github repo.**
  *See the GHC developer team's working conventions re [contributing patches](http://hackage.haskell.org/trac/ghc/wiki/WorkingConventions/Git#Contributingpatches "hackage.haskell.org/trac/ghc/wiki/WorkingConventions/Git#Contributingpatches").*


Building & Installing
=====================

For full information on building GHC, see the [GHC Building Guide] [3].
Here follows a summary - if you get into trouble, the Building Guide
has all the answers.

Before building GHC you may need to install some other tools and
libraries.  See, [Setting up your system for building GHC] [8].

*NB.* In particular, you need [GHC] [1] installed in order to build GHC,
because the compiler is itself written in Haskell.  You also need
[Happy] [4], [Alex] [5], and [Cabal] [9].  For instructions on how
to port GHC to a new platform, see the [GHC Building Guide] [3].

For building library documentation, you'll need [Haddock] [6].  To build
the compiler documentation, you need a good DocBook XML toolchain and
dblatex.

**Quick start**: the following gives you a default build:

    $ perl boot
    $ ./configure
    $ make
    $ make install

The `perl boot` step is only necessary if this is a tree checked out
from git.  For source distributions downloaded from [GHC's web site] [1],
this step has already been performed.

These steps give you the default build, which includes everything
optimised and built in various ways (eg. profiling libs are built).
It can take a long time.  To customise the build, see the file `HACKING`.

Once you have a build you need to keep it going.  You need to keep all
repos in sync with the [sync-all script] [7].  To get the latest changes:

    $ ./sync-all pull
    $ ./sync-all get


Contributors
============

Please see the list of [GHC contributors](http://www.haskell.org/ghc/contributors.html "www.haskell.org/ghc/contributors.html").


  [1]: http://www.haskell.org/ghc/            "www.haskell.org/ghc/"
  [2]: http://hackage.haskell.org/trac/ghc    "hackage.haskell.org/trac/ghc"
  [3]: http://hackage.haskell.org/trac/ghc/wiki/Building
       "hackage.haskell.org/trac/ghc/wiki/Building"
  [4]: http://www.haskell.org/happy/          "www.haskell.org/happy/"
  [5]: http://www.haskell.org/alex/           "www.haskell.org/alex/"
  [6]: http://www.haskell.org/haddock/        "www.haskell.org/haddock/"
  [7]: http://hackage.haskell.org/trac/ghc/wiki/Building/SyncAll
       "http://hackage.haskell.org/trac/ghc/wiki/Building/SyncAll"
  [8]: http://hackage.haskell.org/trac/ghc/wiki/Building/Preparation
       "http://hackage.haskell.org/trac/ghc/wiki/Building/Preparation"
  [9]: http://www.haskell.org/cabal/          "http://www.haskell.org/cabal/"