GHC 9.4.5 is now available

The GHC developers are happy to announce the availability of GHC 9.4.5. Binary
distributions, source distributions, and documentation are available at

Download Page: GHC 9.4.5 download — The Glasgow Haskell Compiler
Blog Post: GHC 9.4.5 is now available — The Glasgow Haskell Compiler

This release is primarily a bugfix release addressing a few issues
found in 9.4.4. These include:

  • Fixes for a number of bugs in the simplifier (#22623, #22718, #22913, 22695,
    #23184, #22998, #22662, #22725).
  • Many bug fixes to the non-moving and parallel GCs (#22264, #22327, #22926,
    #22927, #22929, #22930, #17574, #21840, #22528)
  • A fix a bug with the alignment of RTS data structures that could result in
    segfaults when compiled with high optimisation settings on certain platforms
    (#22975 , #22965).
  • Bumping gmp-tarballs to a version which doesn’t use the reserved x18
    register on AArch64/Darwin systems, and also has fixes for CVE-2021-43618
    (#22497, #22789).
  • A number of improvements to recompilation avoidance with multiple home units
    (#22675, #22677, #22669, #22678, #22679, #22680)
  • Fixes for regressions in the typechecker and constraint solver (#22647,
    #23134, #22516, #22743)
  • Easier installation of binary distribution on MacOS platforms by changing the
    installation Makefile to remove the quarantine attribute when installing.
  • … and many more. See the release notes for a full accounting.

As some of the fixed issues do affect correctness users are encouraged to
upgrade promptly.

We would like to thank Microsoft Azure, GitHub, IOG, the Zw3rk stake pool,
Well-Typed, Tweag I/O, Serokell, Equinix, SimSpace, Haskell Foundation, and
other anonymous contributors whose on-going financial and in-kind support has
facilitated GHC maintenance and release management over the years. Finally,
this release would not have been possible without the hundreds of open-source
contributors whose work comprise this release.

As always, do give this release a try and open a ticket if you see
anything amiss.

Happy compiling,

  • Zubin

The link to the release notes which are supposed to be at is not working

The working link is 2.1. Version 9.4.5 — Glasgow Haskell Compiler 9.4.5 User's Guide

EDIT: Also, the link to the download page should be GHC 9.4.5 download — The Glasgow Haskell Compiler (with underscores). The one with dots gives a HTTP 500 error code.

1 Like

Ah sorry, try

The links might be broken because the documentation is automatically produced by hadrian in GHC 9.4. I will try to update the remaining links.

1 Like

This is released in ghcup now. FreeBSD bindists have not been produced yet.


I have updated Stack’s default setup-info dictionary for these binary distributions, and added GHC 9.4.5’s global hints to global-hints.yaml.


thank you! :slight_smile:

If you are using GHC 9.4.5 on Windows with a dependency on the network package, you will need to bump to the newly-released network- to avoid a glitch.