GHC 9.6.2 is now available

The GHC developers are happy to announce the availability of GHC 9.6.2. Binary
distributions, source distributions, and documentation are available at

This release is primarily a bug-fix release addressing a few issues
found in 9.6.2. These include:

  • a number of simplifier and specialisation issues (#22761, #22549)

  • A bug resulting in crashes of programs using the new listThreads# primop

  • A compiler crash triggered by certain uses of quantified constraints

  • Various bugs in the Javascript backend have been fixed (#23399,
    #23360, #23346)

  • A missing write barrier in the non-moving collector’s handling of selector
    thunks, resulting in undefined behavior (#22930).

  • The non-moving garbage collector’s treatment of weak pointers has been
    revamped which should allow more reliable finalization of Weak#
    closures (#22327)

  • The non-moving garbage collector now bounds the amount of marking it will
    do during the post-marking stop-the-world phase, greatly reducing tail
    latencies in some programs (#22929)

A full accounting of changes can be found in the release notes. 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,

~ Ben


Released in ghcup-metadata


I have updated Stack’s default setup-info dictionary for these binary distributions, and added GHC 9.6.2’s global hints to global-hints.yaml.


I think you meant “9.6.1” :wink:

1 Like

I updated the Fedora ghc9.6 package - the 9.6.2 builds are available now in the Fedora updates-testing and EPEL 9 testing repos.


I updated the actions haskell-actions/setup (and its precursor haskell/actions/setup) to be conscious of GHC 9.6.2.