- Glasgow-haskell-users

GHC 9.14.1-rc2 is now available
by Zubin Duggal 07 Nov '25

07 Nov '25

The GHC developers are very pleased to announce the availability of the second release candidate of GHC 9.14.1. Binary distributions, source distributions, and documentation are available at [downloads.haskell.org][]. The changes from the first release candidate are: * Bump the exceptions submodule to 0.10.11 * Bump the os-string submodule to 2.0.8 * Fix a driver regression causing an infinite loop with cyclic imports GHC 9.14 will bring a number of new features and improvements, including: * Significant improvements in specialisation: * The `SPECIALISE` pragma now allows use of type application syntax * The `SPECIALISE` pragma can be used to specialise for expression arguments as well as type arguments. * Specialisation is now considerably more reliable in the presence of `newtype`s * Significant GHCi improvements including: * Correctness and performance improvements in the bytecode interpreter * Features in the GHCi debugger * Support for multiple home units in GHCi * Implementation of the [Explicit Level Imports proposal][levels] * `RequiredTypeArguments` can now be used in more contexts * SSE/AVX2 support in the x86 native code generator backend * A major update of the Windows toolchain and improved compatibility with macOS Tahoe * ... and many more A full accounting of changes can be found in the [release notes][]. Given the many specialisation improvements and their potential for regression, we would very much appreciate testing and performance characterisation on downstream workloads. Note that while this release makes many improvements in the specialisation optimisation, polymorphic specialisation will remain disabled by default in the final release due to concern over regressions of the sort identified in [#26329][T26329]. Users needing more aggressive specialisation can explicitly enable this feature with the `-fpolymorphic-specialisation` flag. Depending upon our experience with 9.14.1, we may enable this feature by default in a later minor release. We would like to thank the Zw3rk stake pool, Well-Typed, Mercury, Channable, Tweag I/O, Serokell, SimSpace, the 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 have made the Haskell ecosystem what it is today. As always, do give this release a try and open a [ticket][] if you see anything amiss. [downloads.haskell.org] https://downloads.haskell.org/ghc/9.14.1-rc2 [release notes]: https://downloads.haskell.org/ghc/9.14.1-rc2/docs/users_guide/9.14.1-notes.… [ticket]: https://gitlab.haskell.org/ghc/homepage/-/issues/new [macos]: https://gitlab.haskell.org/ghc/ghc/-/issues/26166 [T26329]: https://gitlab.haskell.org/ghc/ghc/-/issues/26329 [levels]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0682-e…

3 3

Re: [Haskell-cafe] Re: GHC 9.14.1-rc2 is now available
by George Colpitts 06 Nov '25

06 Nov '25

solved it for me also. thanks! On Thu, Nov 6, 2025 at 12:44 PM Noon van der Silk <noonsilk(a)gmail.com> wrote: > Success. > > On Thu, 6 Nov 2025 at 16:41, Zubin Duggal <zubin(a)well-typed.com> wrote: > >> Try refreshing https://downloads.haskell.org/ghc/9.14.1-rc2/, >> I purged the CDN cache. >> >> On 25/11/06 12:34, George Colpitts wrote: >> >I get a 404 Not Found when I click on any of the darwin releases, e.g. >> > >> https://downloads.haskell.org/ghc/9.14.1-rc2/ghc-9.14.0.20251031-aarch64-ap… >> > >> >On Thu, Nov 6, 2025 at 12:12 PM Zubin Duggal <zubin(a)well-typed.com> >> wrote: >> > >> >> The GHC developers are very pleased to announce the availability of the >> >> second release candidate of GHC 9.14.1. Binary distributions, source >> >> distributions, and documentation are available at [ >> downloads.haskell.org >> >> ][]. >> >> >> >> The changes from the first release candidate are: >> >> >> >> * Bump the exceptions submodule to 0.10.11 >> >> * Bump the os-string submodule to 2.0.8 >> >> * Fix a driver regression causing an infinite loop with cyclic imports >> >> >> >> GHC 9.14 will bring a number of new features and improvements, >> including: >> >> >> >> * Significant improvements in specialisation: >> >> * The `SPECIALISE` pragma now allows use of type application syntax >> >> * The `SPECIALISE` pragma can be used to specialise for expression >> >> arguments >> >> as well as type arguments. >> >> * Specialisation is now considerably more reliable in the presence >> of >> >> `newtype`s >> >> >> >> * Significant GHCi improvements including: >> >> * Correctness and performance improvements in the bytecode >> interpreter >> >> * Features in the GHCi debugger >> >> * Support for multiple home units in GHCi >> >> >> >> * Implementation of the [Explicit Level Imports proposal][levels] >> >> >> >> * `RequiredTypeArguments` can now be used in more contexts >> >> >> >> * SSE/AVX2 support in the x86 native code generator backend >> >> >> >> * A major update of the Windows toolchain and improved compatibility >> with >> >> macOS Tahoe >> >> >> >> * ... and many more >> >> >> >> A full accounting of changes can be found in the [release notes][]. >> Given >> >> the >> >> many specialisation improvements and their potential for regression, we >> >> would >> >> very much appreciate testing and performance characterisation on >> downstream >> >> workloads. >> >> >> >> Note that while this release makes many improvements in the >> specialisation >> >> optimisation, polymorphic specialisation will remain disabled by >> default >> >> in the >> >> final release due to concern over regressions of the sort identified in >> >> [#26329][T26329]. Users needing more aggressive specialisation can >> >> explicitly >> >> enable this feature with the `-fpolymorphic-specialisation` flag. >> Depending >> >> upon our experience with 9.14.1, we may enable this feature by default >> in a >> >> later minor release. >> >> >> >> We would like to thank the Zw3rk stake pool, Well-Typed, Mercury, >> >> Channable, >> >> Tweag I/O, Serokell, SimSpace, the 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 have made the Haskell ecosystem what it is today. >> >> >> >> As always, do give this release a try and open a [ticket][] if you see >> >> anything amiss. >> >> >> >> >> >> [downloads.haskell.org] https://downloads.haskell.org/ghc/9.14.1-rc2 >> >> [release notes]: >> >> >> https://downloads.haskell.org/ghc/9.14.1-rc2/docs/users_guide/9.14.1-notes.… >> >> [ticket]: https://gitlab.haskell.org/ghc/homepage/-/issues/new >> >> [macos]: https://gitlab.haskell.org/ghc/ghc/-/issues/26166 >> >> [T26329]: https://gitlab.haskell.org/ghc/ghc/-/issues/26329 >> >> [levels]: >> >> >> https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0682-e… >> >> _______________________________________________ >> >> Glasgow-haskell-users mailing list -- >> glasgow-haskell-users(a)haskell.org >> >> To unsubscribe send an email to >> glasgow-haskell-users-leave(a)haskell.org >> >> >> _______________________________________________ >> Haskell-Cafe mailing list -- haskell-cafe(a)haskell.org >> To (un)subscribe, modify options or view archives go to: >> Only members subscribed via the mailman list are allowed to post. > > > > -- > Noon van der Silk > > http://silky.github.io/ > > "My programming language is kindness." >

1 0

GHC 9.12.3 status update
by Zubin Duggal 28 Oct '25

28 Oct '25

Hi all, I'm currently working on the final set of backports for GHC 9.12.3-rc2. This has been delayed due to #26166 making bootstrapping GHC impossible on the new macOS release. I am currently in the process of backporting the fix for this ticket (among a few other patches) to GHC 9.12. I expect to have rc2 out in the next few days, by the end of this week. Cheers, Zubin. #26166: https://gitlab.haskell.org/ghc/ghc/-/issues/26166

1 0

GHC 9.14.1-alpha3 is now available
by Ben Gamari 09 Oct '25

09 Oct '25

The GHC developers are very pleased to announce the availability of the third alpha release of GHC 9.14.1. Binary distributions, source distributions, and documentation are available at [downloads.haskell.org] GHC 9.14 will bring a number of new features and improvements, including: * Significant improvements in specialisation: * The `SPECIALISE` pragma now allows use of type application syntax * The `SPECIALISE` pragma can be used to specialise for expression arguments as well as type arguments. * Specialisation is now considerably more reliable in the presence of `newtype`s * Significant improvements GHCi including: * Correctness and performance improvements in the bytecode interpreter * Features in the GHCi debugger * Support for multiple home units in GHCi * Implementation of the [Explicit Level Imports proposal][levels] * `RequiredTypeArgments` can now be used in more contexts * SSE/AVX2 support in the x86 native code generator backend * A major update of the Windows toolchain * ... and many more A full accounting of changes can be found in the [release notes]. Given the many specialisation improvements and their potential for regression, we would very much appreciate testing and performance characterisation on downstream workloads. Note that while this release makes many improvements in the specialisation optimisation, polymorphic specialisation will remain disabled by default in the final release due to concern over regressions of the sort identified in [#26329]. Users needing more aggressive specialisation can explicitly enable this feature with the `-fpolymorphic-specialisation` flag. Depending upon our experience with 9.14.1, we may enable this feature by default in a later minor release. This is the third alpha release of 9.14.1. This comes later than expected in part due to work on a resolving a regression in the macOS 26 ([#26166]) which threatened the usability of the release. While a complete fix for this issue is not present in this alpha, we have done enough work to have confidence that it will be in finished for the release candidate which we expect should come the week of 27 October. We would like to thank the Zw3rk stake pool, Well-Typed, Mercury, Channable, Tweag I/O, Serokell, SimSpace, the 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 have made the Haskell ecosystem what it is today. As always, do give this release a try and open a [ticket] if you see anything amiss. Cheers, - Ben [downloads.haskell.org] https://downloads.haskell.org/ghc/9.14.1-alpha3 [release notes]: https://downloads.haskell.org/ghc/9.14.1-alpha3/docs/users_guide/9.14.1-not… [ticket]: https://gitlab.haskell.org/ghc/homepage/-/issues/new [#26166]: https://gitlab.haskell.org/ghc/ghc/-/issues/26166 [#26329]: https://gitlab.haskell.org/ghc/ghc/-/issues/26329 [levels]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0682-e…

1 0

GHC 9.12.3-rc1 is now available
by Zubin Duggal 22 Sep '25

22 Sep '25

The GHC developers are very pleased to announce the availability of the release candidate for GHC 9.12.3. Binary distributions, source distributions, and documentation are available at [downloads.haskell.org][] and via [GHCup](https://www.haskell.org/ghcup/). GHC 9.12.3 is a bug-fix release fixing several issues of a variety of severities and scopes. A full accounting of these fixes can be found in the [release notes][]. As always, GHC's release status, including planned future releases, can be found on the GHC Wiki [status][]. This release candidate will have a two-week testing period. If all goes well the final release will be available the week of 2 October 2025. We would like to thank Well-Typed, Tweag I/O, Juspay, QBayLogic, Channable, Serokell, SimSpace, the 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. [release notes]: https://gitlab.haskell.org/ghc/ghc/-/blob/ghc-9.12/docs/users_guide/9.12.3-… [status]: https://gitlab.haskell.org/ghc/ghc/-/wikis/GHC-status [downloads.haskell.org] https://downloads.haskell.org/ghc/9.12.3-rc1 [ticket]: https://gitlab.haskell.org/ghc/ghc/-/issues/new

1 0

GHC 9.14.1-alpha2 is now available
by Ben Gamari 15 Sep '25

15 Sep '25

The GHC developers are very pleased to announce the availability of the second alpha prerelease of GHC 9.14.1. Binary distributions, source distributions, and documentation are available at [downloads.haskell.org] GHC 9.14 will bring a number of new features and improvements, including: * Significant improvements in specialisation: * The `SPECIALISE` pragma now allows use of type application syntax * The `SPECIALISE` pragma can be used to specialise for expression arguments as well as type arguments. * Specialisation is now considerably more reliable in the presence of `newtype`s * Significant improvements in the GHCi debugger * Record fields can be defined to be non-linear when `LinearTypes` is enabled. * `RequiredTypeArgments` can now be used in more contexts * SSE/AVX2 support in the x86 native code generator backend * A major update of the Windows toolchain * ... and many more A full accounting of changes can be found in the [release notes]. Given the many specialisation improvements and their potential for regression, we would very much appreciate testing and performance characterisation on downstream workloads. Observant readers of these prerelease announcements will note that polymorphic specialisation has been dropped from alpha 2. This measure was taken out of an abundance of caution after finding a miscompilation during testing of alpha 1. While this bug will be fixed in the next alpha, we expect to keep polymorphic specialisation disabled by default in the final release. Users needing more aggressive specialisation can explicitly enable this feature with the `-fpolymorphic-specialisation` flag. Depending upon our experience with 9.14.1, we may enable this feature by default in a later minor release. This is the second of three expected alpha prereleases. We expect the next (third) alpha will come 23 Sept. 2025, with the release candidate coming 7 Oct. 2025. We would like to thank the Zw3rk stake pool, Well-Typed, Mercury, Channable, Tweag I/O, Serokell, SimSpace, the 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 have made the Haskell ecosystem what it is today. As always, do give this release a try and open a [ticket] if you see anything amiss. [downloads.haskell.org] https://downloads.haskell.org/ghc/9.14.1-alpha2 [release notes]: https://downloads.haskell.org/ghc/9.14.1-alpha2/docs/users_guide/9.14.1-not… [ticket]: https://gitlab.haskell.org/ghc/homepage/-/issues/new

2 1

GHC 9.10.3 is now available
by Zubin Duggal 11 Sep '25

11 Sep '25

The GHC developers are very pleased to announce the availability of the final release for GHC 9.10.3. Binary distributions, source distributions, and documentation are available at [downloads.haskell.org][]. GHC 9.10.3 is a bug-fix release fixing many issues of a variety of severities and scopes, including: * Fix a number of crashes in the compiler frontend (#25960, #25004, #25056) * Fix incorrect results in the NCG (#25601, #26061) * Support for far jumps in the AArch64 NCG (#24648) * A fix for a segfault in the RTS when running certain code involving STM (#26205) * And many more! A full accounting of these fixes can be found in the [release notes][]. As always, GHC's release status, including planned future releases, can be found on the GHC Wiki [status][]. We would like to thank Well-Typed, Tweag I/O, Juspay, QBayLogic, Channable, Serokell, SimSpace, the 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. [release notes]: https://downloads.haskell.org/~ghc/9.10.3/docs/users_guide/9.10.3-notes.html [status]: https://gitlab.haskell.org/ghc/ghc/-/wikis/GHC-status [downloads.haskell.org] https://downloads.haskell.org/ghc/9.10.3 [ticket]: https://gitlab.haskell.org/ghc/ghc/-/issues/new

1 0

GHC 9.14.1-alpha1 is now available
by Ben Gamari 20 Aug '25

20 Aug '25

The GHC developers are very pleased to announce the availability of the first alpha prerelease of GHC 9.14.1. Binary distributions, source distributions, and documentation are available at [downloads.haskell.org] GHC 9.14 will bring a number of new features and improvements, including: * Significant improvements in specialisation: * The SPECIALISE pragma now allows use of type application syntax * The SPECIALISE pragma can be used to specialise for expression arguments as well as type arguments. * Specialisation is now considerably more reliable in the presence of newtypes * the specialiser is now able to produce specialisations with polymorphic typeclass constraints, considerably broadening its scope. * Significant improvements in the GHCi debugger * Record fields can be defined to be non-linear when LinearTypes is enabled. * RequiredTypeArgments can now be used in more contexts * SSE/AVX spport in the x86 native code generator backend * A major update of the Windows toolchain * ... and many more A full accounting of changes can be found in the release notes [1]. Given the many specialisation improvements and their potential for regression, we would very much appreciate testing and performance characterisation on downstream workloads. Due to unexpected complications, this initial prerelease comes a bit later than expected. Consequently, we expect to have only two alphas prior to the release candidate, in contrast to the scheduled three. We expect the next alpha will come the seek of 9 Sept. 2025, while the third will come 23 Sept. 2025, with the release candidate coming 7 Oct. 2025. We would like to thank the Zw3rk stake pool, Well-Typed, Mercury, Channable, Tweag I/O, Serokell, SimSpace, the 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. [downloads.haskell.org] https://downloads.haskell.org/ghc/9.14.1-alpha1 [release notes]: https://downloads.haskell.org/ghc/9.14.1-alpha1/docs/users_guide/9.14.1-not… [ticket]: https://gitlab.haskell.org/ghc/homepage/-/issues/new

1 1

GHC 9.10.3-rc4 is now available
by Zubin Duggal 18 Aug '25

18 Aug '25

The GHC developers are very pleased to announce the availability of the fourth release candidate for GHC 9.10.3. Binary distributions, source distributions, and documentation are available at [downloads.haskell.org][] and via [GHCup](https://www.haskell.org/ghcup/). GHC 9.10.3 is a bug-fix release fixing over 50 issues of a variety of severities and scopes. A full accounting of these fixes can be found in the [release notes][]. As always, GHC's release status, including planned future releases, can be found on the GHC Wiki [status][]. The changes from the third release candidate are: - A fix for a rare segfault with code involving STM (#26205) - A fix for the `naturalAndNot` returning bogus results (#26205) - A fix for a crash in the renamer (#25056) This release candidate will have a two-week testing period. If all goes well the final release will be available the week of 1 September 2025. We would like to thank Well-Typed, Tweag I/O, Juspay, QBayLogic, Channable, Serokell, SimSpace, the 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. [release notes]: https://gitlab.haskell.org/ghc/ghc/-/blob/ghc-9.10/docs/users_guide/9.10.3-… [status]: https://gitlab.haskell.org/ghc/ghc/-/wikis/GHC-status [downloads.haskell.org] https://downloads.haskell.org/ghc/9.10.3-rc4 [ticket]: https://gitlab.haskell.org/ghc/ghc/-/issues/new

1 0

GHC 9.10.3-rc3 is now available
by Zubin Duggal 08 Aug '25

08 Aug '25

The GHC developers are very pleased to announce the availability of the third release candidate for GHC 9.10.3. Binary distributions, source distributions, and documentation are available at [downloads.haskell.org][] and via [GHCup](https://www.haskell.org/ghcup/). GHC 9.10.3 is a bug-fix release fixing over 50 issues of a variety of severities and scopes. A full accounting of these fixes can be found in the [release notes][]. As always, GHC's release status, including planned future releases, can be found on the GHC Wiki [status][]. The changes from the second release candidate are: - Reverting a change the exports of the `Backtrace` constructor in the base library that was backported due to confusion on CLC approvals (!14587) - Reverting a change to the configure script (!14324) that dropped probing for ld.gold This release candidate will have a two-week testing period. If all goes well the final release will be available the week of 22 August 2025. We would like to thank Well-Typed, Tweag I/O, Juspay, QBayLogic, Channable, Serokell, SimSpace, the 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. [release notes]: https://gitlab.haskell.org/ghc/ghc/-/blob/ghc-9.10/docs/users_guide/9.10.3-… [status]: https://gitlab.haskell.org/ghc/ghc/-/wikis/GHC-status [downloads.haskell.org] https://downloads.haskell.org/ghc/9.10.3-rc3 [ticket]: https://gitlab.haskell.org/ghc/ghc/-/issues/new

1 0