
   =============================================================
    The (Interactive) Glasgow Haskell Compiler -- version 7.4.1
   =============================================================

The GHC Team is pleased to announce a new major release of GHC, 7.4.1.

Here are some of the highlights of the 7.4 branch since 7.2 and 7.0:

  * The Num class no longer has Eq or Show superclasses.

  * There is a new feature Safe Haskell (-XSafe, -XTrustworthy, -XUnsafe).
    The design has changed since 7.2.

  * There is a new feature kind polymorphism (-XPolyKinds).
    A side-effect of this is that, when the extension is not enabled, in
    certain circumstances kinds are now defaulted to * rather than being
    inferred.

  * There is a new feature constraint kinds (-XConstraintKinds).

  * It is now possible to give any sort of declaration at the ghci prompt.
    For example, you can now declare datatypes within ghci.

  * The profiling and hpc implementations have been merged and overhauled.
    Visible changes include renaming of profiling flags, and a new
    semantics for the cost-centre stacks (which should in most cases
    result in more useful and intuitive profiles). The +RTS -xc flag now
    also gives a stack trace.

  * It is now possible to write compiler plugins.

  * DPH support has been significantly improved.

  * There is now preliminary support for registerised compilation using
    LLVM on the ARM platform.

Full release notes are here:

  http://www.haskell.org/ghc/docs/7.4.1/html/users_guide/release-7-4-1.html

How to get it
~~~~~~~~~~~~~

The easy way is to go to the web page, which should be self-explanatory:

        http://www.haskell.org/ghc/

We supply binary builds in the native package format for many
platforms, and the source distribution is available from the same
place.

Packages will appear as they are built - if the package for your
system isn't available yet, please try again later.


Background
~~~~~~~~~~

Haskell is a standard lazy functional programming language.

GHC is a state-of-the-art programming suite for Haskell.  Included is
an optimising compiler generating good code for a variety of
platforms, together with an interactive system for convenient, quick
development.  The distribution includes space and time profiling
facilities, a large collection of libraries, and support for various
language extensions, including concurrency, exceptions, and foreign
language interfaces (C, whatever).  GHC is distributed under a
BSD-style open source license.

A wide variety of Haskell related resources (tutorials, libraries,
specifications, documentation, compilers, interpreters, references,
contact information, links to research groups) are available from the
Haskell home page (see below).


On-line GHC-related resources
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Relevant URLs on the World-Wide Web:

GHC home page              http://www.haskell.org/ghc/
GHC developers' home page  http://hackage.haskell.org/trac/ghc/
Haskell home page          http://www.haskell.org/


Supported Platforms
~~~~~~~~~~~~~~~~~~~

The list of platforms we support, and the people responsible for them,
is here:

   http://hackage.haskell.org/trac/ghc/wiki/Contributors

Ports to other platforms are possible with varying degrees of
difficulty.  The Building Guide describes how to go about porting to a
new platform:

    http://hackage.haskell.org/trac/ghc/wiki/Building


Developers
~~~~~~~~~~

We welcome new contributors.  Instructions on accessing our source
code repository, and getting started with hacking on GHC, are
available from the GHC's developer's site run by Trac:

  http://hackage.haskell.org/trac/ghc/


Mailing lists
~~~~~~~~~~~~~

We run mailing lists for GHC users and bug reports; to subscribe, use
the web interfaces at

    http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
    http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs

There are several other haskell and ghc-related mailing lists on
www.haskell.org; for the full list, see

    http://www.haskell.org/mailman/listinfo/

Some GHC developers hang out on #haskell on IRC, too:

    http://www.haskell.org/haskellwiki/IRC_channel

Please report bugs using our bug tracking system.  Instructions on
reporting bugs can be found here:

    http://www.haskell.org/ghc/reportabug

