GHC 8.4.1 released

Ben Gamari - 2018-03-08

The GHC developers are very happy to announce the 8.4.1 release of Glasgow Haskell Compiler. Binary and source distributions can be found at

This is the third major release in the GHC 8 series. As such, the focus of this release is performance, stability, and consolidation. Consequently numerous cleanups can be seen throughout the compiler including,

  • Further refinement of TypeInType, including significant improvements in error messages.

  • Improvements in code generation resulting in noticeable performance improvements in some types of programs.

  • Core library improvements, including phase 2 of the Semigroup/Monoid proposal

  • Many improvements to instance deriving

  • The resolution of nearly 300 other tickets

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

There are a few changes in release-engineering matters that should be noted,

  • This is GHC’s first release on it’s new, accelerated release schedule. From now on GHC will produce one release every six months.

  • While we typically strive to produce OpenBSD builds, the gcc shipped with OpenBSD 6.1 is unfortunately too old to compile this release.

  • FreeBSD builds are still in progress

This release has been the result of approximately six months of work by over one hundred code contributors. Thanks to everyone who has helped in writing patches, testing, reporting bugs, and offering feedback over the last year.

As always, let us know if you encounter trouble.

How to get it

This release can be downloaded from

For older versions see

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


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