Posts for the month of May 2016

GHC 8.0.1 is available!

The GHC developers are very pleased to announce the release of the first new super-major version of our Haskell compiler in six years, GHC 8.0.1. This release features dozens of exciting developments including,

  • A more refined interface for implicit call-stacks, allowing libraries to provide more helpful runtime error messages to users
  • The introduction of the DuplicateRecordFields language extension, allowing multiple datatypes to declare fields of the same name
  • Significant improvements in error message readability and content, including facilities for libraries to provide custom error messages, more aggressive warnings for fragile rewrite rules, and more helpful errors for missing imports
  • A rewritten and substantially more thorough pattern match checker, providing more precise exhaustiveness checking in GADT pattern matches
  • More reliable debugging information including experimental backtrace support, allowing better integration with traditional debugging tools
  • Support for desugaring do-notation to use Applicative combinators, allowing the intuitive do notation to be used in settings which previously required the direct use of Applicative combinators
  • The introduction of Strict and StrictData language extensions, allowing modules to be compiled with strict-by-default evaluation of bindings
  • Great improvements in portability, including more reliable linking on Windows, a new PPC64 code generator, support for the AIX operating system, unregisterised m68k support, and significant stabilization on ARM targets
  • A greatly improved user's guide, with beautiful and modern PDF and HTML output
  • Introduction of type application syntax, reducing the need for proxies
  • More complete support for pattern synonyms, including record pattern synonyms and the ability to export patterns "bundled" with a type, as you would a data constructor
  • Support for injective type families and recursive superclass relationships
  • An improved generics representation leveraging GHC's support for type-level literals
  • The TypeInType extension, which unifies types and kinds, allowing GHC to reason about kind equality and enabling promotion of more constructs to the type level
  • ...and more!

A more thorough list of the changes included in this release can be found in the release notes,

As always, we have collected various points of interest for users of previous GHC releases on the GHC 8.0 migration page, Please let us know if you encounter anything missing or unclear on this page.

This release is the culmination of nearly eighteen months of effort by over one hundred contributors. We'd like to thank everyone who has contributed code, bug reports, and feedback over the past year. It's only because of their efforts that GHC continues to evolve.

How to get it

Both the source tarball and binary distributions for a wide variety of platforms are available here.


Haskell is a standardized lazy functional programming language.

The Glasgow Haskell Compiler (GHC) is a state-of-the-art programming suite for Haskell. Included is an optimising compiler generating efficient 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. GHC is distributed under a BSD-style open source license.

Supported Platforms

The list of platforms we support, and the people responsible for them, can be found on the GHC wiki

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


We welcome new contributors. Instructions on getting started with hacking on GHC are available from GHC's developer site.

Community Resources

There are mailing lists for GHC users, develpoers, and monitoring bug tracker activity; to subscribe, use the Mailman web interface.

There are several other Haskell and GHC-related mailing lists on; for the full list, see the lists page.

Some GHC developers hang out on the #ghc and #haskell of the Freenode IRC network, too. See the Haskell wiki for details.

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