- ghc-devs - Haskell.org

Re: [Haskell-cafe] Re: GHC 9.14.1-rc2 is now available
by George Colpitts 07 Nov '25

07 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." >

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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…

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Static Binary with Haskell Repl
by glfmn 06 Nov '25

06 Nov '25

Hello! My name is Gwen and I am investigating an interesting problem related to tidal cycles, a haskell library for patterning music. https://tidalcycles.org/ We have the desire to distribute tidal cycles without the need for the end user to install a full haskell development environment (ghc/cabal/stack, etc). However, the interface for tidal cycles is a haskell repl. We essentially want to create an executable that will start a "pre-heated" ghci session which has the tidal libraries loaded, that we can compile on one machine with a haskell toolchain, and run on a system without one. Another use-case would be to evaluate tidal patterns authored by a musician inside of a Digital Audio Workstation. I am investigating whether this is possible. Does/could the haskell ghc api support this kind of use-case? If I was to support a similar use-case with a language like janet (which is designed to exist in a host application), the solution would be to host the compiled bytecode in the application, and populate the interpereter or virtual machine's environment with those symbols so it could find the pre-compiled bytecode hosted inside the executable. Thanks, Gwen Links with additional context: - https://github.com/haskell-hint/hint/issues/156 - https://github.com/haskell-hint/hint/issues/80

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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

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GHC 9.14.1-alpha3 is now available
by Ben Gamari 10 Oct '25

10 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…

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GitLab maintenance window tonight
by Ben Gamari 01 Oct '25

01 Oct '25

Hi all, Tonight (around 19:00 ET) I will be carrying out a GitLab upgrade and a bit of work to mitigate crawler traffic. As usual, I hope this will be less than ten minutes of downtime. Cheers, - Ben

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GHC Developer retreat 2026
by Magnus Viernickel 30 Sep '25

30 Sep '25

Dear GHC developers and contributors, Teo Camarasu and I, Magnus Viernickel are planning a GHC Developer retreat for people interested in cabal, HLS and GHC hacking in Hathersage, UK. The main goal is to create an informal and productive atmosphere for focused GHC hacking, just like the Nix ecosystem does with their "sprints" and like Andreas Klebinger and Matthew Pickering planned with their GHC Week 5 years ago before the pandemic cancelled their plans. For more information, please have a look at: https://ghc-dev-retreat.mangoiv.com/ If that makes you interested, please fill in our interest check form at: https://forms.gle/JTD9mgG24ejM4ybe6 Mind that we currently do not know - if the venue is fixed (we might need to switch to a bigger one if there are a lot more people interested than the current capacity of 14 people) - the concrete costs (this will depend on how many people are interested, the Sladenlodge is not that expensive in the off-season though and I think it will be very manageable, esp. when it's fully booked) If you have any ideas or questions, please feel free to reach out. Best Teo and Magnus

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mistakenly deleted lables "bug" and "needs triage" from a new bug, can somebody add them ?
by George Colpitts 26 Sep '25

26 Sep '25

Hello I created a new bug, #26441, but mistakenly deleted /label ~bug /label ~"needs triage" from the description and when I add them it doesn't seem to do anything. Can somebody with the appropriate permissions add them now. Thanks George

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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

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CStub in inline-java
by Facundo Domínguez 19 Sep '25

19 Sep '25

Dear devs, I upgraded inline-java [1] to use GHC 9.10.2 recently. inline-java has a GHC plugin responsible for embedding JVM bytecode in Haskell modules. This message is to consult on the most appropriate way to do it. The byte code is placed in a C literal array of bytes, and the C code is added in mg_foreign together with C constructor functions that run when loading the module to add the bytecode to a global bytecode table [2]. The global bytecode table is then fed to the JVM when initializing inline-java. The GHC API in 9.10.2 requires creating a CStub which does have a field to indicate constructor functions [3], but I wouldn't know how to create the CLabels it needs. So instead, I just put the constructor functions in the getCStub field, and set getInitializers to an empty list. The constructor functions seem to run at initialization just the same. Should inline-java do this differently? Thanks in advance! Facundo [1] https://github.com/tweag/inline-java [2] https://github.com/tweag/inline-java/blob/c6b590c29ef9190164dec3a235b8e386c… [3] https://gitlab.haskell.org/ghc/ghc/-/blob/3c37d30b07fc85fe09452f4ce250aec42… data CStub = CStub { getCStub :: SDoc , getInitializers :: [CLabel] -- ^ Initializers to be run at startup -- See Note [Initializers and finalizers in Cmm] in -- "GHC.Cmm.InitFini". , getFinalizers :: [CLabel] -- ^ Finalizers to be run at shutdown } -- All views and opinions expressed in this email message are the personal opinions of the author and do not represent those of the organization or its customers.

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