August 2023 - ghc-devs

Request for approval of account
by Mark Seemann 25 Jun '25

25 Jun '25

Hello I’d like to report a bug in GHC because an error message tells me to do so. In order to do that, I’m trying to follow the guidelines in https://gitlab.haskell.org/ghc/ghc/-/wikis/report-a-bug, so I’ve created an account. The next step, as I understand it, is to use this mailing list to request approval for he account. I’m hereby doing that. TIA Mark Seemann

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[ANNOUNCE] GHC 9.4.7 is now available
by Zubin Duggal 26 Aug '23

26 Aug '23

The GHC developers are happy to announce the availability of GHC 9.4.7. Binary distributions, source distributions, and documentation are available at https://downloads.haskell.org/ghc/9.4.7 The GHC developers are happy to announce the availability of GHC 9.4.7. Binary distributions, source distributions, and documentation are available at [downloads.haskell.org](https://downloads.haskell.org/ghc/9.4.7). This release is primarily a bugfix release addressing some issues found in 9.4.6. These include: * A bump to bytestring-0.11.5.2 allowing GHC to be bootstrapped on systems where the bootstrap compiler is built with the `pthread_condattr_setclock` symbol available (#23789). * A number of bug fixes for scoping bugs in the specialiser, preventing simplifier panics (#21391, #21689, #21828, #23762). * Distributing dynamically linked alpine bindists (#23349, #23828). * A bug fix for the release notes syntax, allowing them to built on systems with older python and sphinx versions (#23807, #23818). * ... and a few more. See the [release notes] for a full accounting. 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 [ticket]: https://gitlab.haskell.org/ghc/ghc/-/issues/new [release notes]: https://downloads.haskell.org/~ghc/9.4.7/docs/users_guide/9.4.7-notes.html

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[ANNOUNCE] GHC 9.4.6 is now available
by Ben Gamari 26 Aug '23

26 Aug '23

The GHC developers are happy to announce the availability of GHC 9.4.6. Binary distributions, source distributions, and documentation are available at https://downloads.haskell.org/ghc/9.4.6 This release is primarily a bugfix release addressing some issues found in 9.4.6. These include: * Many bug fixes for the simplifier, preventing compiler panics, loops and incorrect code generation (#22761, #22549, #23208, #22761, #22272, #23146, #23012, #22547). * Bug fixes for the typechecker involving newtype family instances, making type equalities more robust and bugs having to do with defaulting representation polymorphic type variables (#23329, #23333, #23143, #23154, #23176). * Some bug fixes for code generation, particularly on the aarch64 backend, including adding more memory barriers for array read operations (#23541, #23749). * Some bug fixes for windows builds, ensuring the reliablility of IO manager shutdown and a bug fix for the RTS linker on windows (#23691, #22941). * A bug fix for the non-moving GC ensuring mutator allocations are properly accounted for (#23312). * A bug fix preventing some segfaults by ensuring that pinned allocations respect block size (#23400). * Many bug fixes for the bytecode interpreter, allowing a greater subset of the language to be interpreted (#22376, #22840, #22051, #21945, #23068, #22958). * ... and a few 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 & Ben [ticket]: https://gitlab.haskell.org/ghc/ghc/-/issues/new [release notes]: https://downloads.haskell.org/~ghc/9.4.6/docs/users_guide/9.4.6-notes.html

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Library module naming
by Simon Peyton Jones 25 Aug '23

25 Aug '23

Friends I am keen to complete discussion on HF tech proposal 53 <https://github.com/haskellfoundation/tech-proposals/pull/53> which is about the naming convention for modules in base, ghc-experimental, ghc-internal, etc. I think it's done. Any views? Simon

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[ANNOUNCE] GHC 9.8.1-alpha3 is now available
by Ben Gamari 24 Aug '23

24 Aug '23

The GHC developers are very pleased to announce the availability of the third alpha prerelease of GHC 9.8.1. Binary distributions, source distributions, and documentation are available at https://downloads.haskell.org/ghc/9.8.1-alpha3 GHC 9.8 will bring a number of new features and improvements, including: * Preliminary support the `TypeAbstractions` language extension, allowing types to be bound in type declarations [TypeAbstractions]. * Support for the `ExtendedLiterals` extension, providing syntax for non-word-sized numeric literals in the surface language [extended-literals] * Improved rewrite rule matching behavior, allowing limited matching of higher-order patterns * Better support for user-defined warnings by way of the `WARNING` pragma [warnings] * The introduction of the new `GHC.TypeError.Unsatisfiable` constraint, allowing more predictable user-defined type errors [unsatisfiable] * Implementation of the export deprecation proposal, allowing module exports to be marked with `DEPRECATE` pragmas [deprecated-exports] * The addition of build semaphore support for parallel compilation; with coming support in `cabal-install` this will allow better use of parallelism in multi-package builds [jsem] * More efficient representation of info table provenance information, reducing binary sizes by over 50% in some cases when `-finfo-table-map` is in use A full accounting of changes can be found in the [release notes]. This alpha includes roughly a dozen changes relative to alpha 2, including what we believe should be nearly the last changes to GHC's boot libraries. We would like to thank GitHub, IOG, the Zw3rk stake pool, Well-Typed, Tweag I/O, Serokell, Equinix, 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. Happy compiling, ~ Ben [TypeAbstractions]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0425-d… [extended-literals]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0451-s… [unsatisfiable]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0433-u… [warnings]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0541-w… [deprecated-exports]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0134-d… [jsem]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0540-j… [release notes]: https://downloads.haskell.org/ghc/9.8.1-alpha3/docs/users_guide/9.8.1-notes…

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Re: [Haskell-cafe] [ANNOUNCE] GHC 9.8.1-alpha2 is now available
by Arnaud Spiwack 24 Aug '23

24 Aug '23

😱 Thanks Sam and Noon! I'm obviously great at copy-pasting. On Tue, 22 Aug 2023 at 14:36, Noon van der Silk <noonsilk(a)gmail.com> wrote: > Hey Arnaud, > > > For the sake of the future announcements, the first item should have > s/TypeApplications/TypeApplications/ > > I assume you mean "TypeApplications" instead of "TypeApplications", right? > > :D > > -- > Noon > > > On Tue, 22 Aug 2023 at 13:30, Arnaud Spiwack <arnaud.spiwack(a)tweag.io> > wrote: > >> Thanks Ben. >> >> For the sake of the future announcements, the first item should have >> s/TypeApplications/TypeApplications/ >> >> >> On Thu, 10 Aug 2023 at 17:09, Ben Gamari <ben(a)well-typed.com> wrote: >> >>> >>> The GHC developers are very pleased to announce the availability of the >>> second alpha prerelease of GHC 9.8.1. Binary distributions, source >>> distributions, and documentation are available at >>> >>> https://downloads.haskell.org/ghc/9.8.1-alpha2 >>> >>> GHC 9.8 will bring a number of new features and improvements, including: >>> >>> * Preliminary support the `TypeApplications` language extension >>> [type-binders], >>> allowing types to be bound in type declarations. >>> >>> * Support for the `ExtendedLiterals` extension, providing syntax for >>> non-word-sized numeric literals in the surface language >>> [extended-literals] >>> >>> * Improved rewrite rule matching behavior, allowing limited matching of >>> higher-order patterns >>> >>> * Better support for user-defined warnings by way of the `WARNING` >>> pragma [warnings] >>> >>> * The introduction of the new `GHC.TypeError.Unsatisfiable` >>> constraint, allowing more predictable user-defined type errors >>> [unsatisfiable] >>> >>> * Implementation of the export deprecation proposal, allowing module >>> exports to be marked with `DEPRECATE` pragmas [deprecated-exports] >>> >>> * The addition of build semaphore support for parallel compilation; >>> with coming support in `cabal-install` this will allow better use of >>> parallelism in multi-package builds [jsem] >>> >>> * More efficient representation of info table provenance information, >>> reducing binary sizes by over 50% in some cases when >>> `-finfo-table-map` is in use >>> >>> A full accounting of changes can be found in the [release notes]. >>> This alpha includes around two dozen bug-fixes relative to alpha 1. >>> >>> We would like to thank GitHub, IOG, the Zw3rk stake pool, >>> Well-Typed, Tweag I/O, Serokell, Equinix, 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. >>> >>> Happy compiling, >>> >>> ~ Ben >>> >>> >>> [type-binders]: >>> https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0425-d… >>> [extended-literals >>> <https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0425-d…>]: >>> >>> https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0451-s… >>> [unsatisfiable]: >>> https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0433-u… >>> [warnings]: >>> https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0541-w… >>> [deprecated-exports >>> <https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0541-w…>]: >>> >>> https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0134-d… >>> [jsem]: >>> https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0540-j… >>> [release notes]: >>> https://downloads.haskell.org/ghc/9.8.1-alpha2/docs/users_guide/9.8.1-notes… >>> [ticket]: https://gitlab.haskell.org/ghc/ghc/-/issues/new >>> _______________________________________________ >>> Haskell-Cafe mailing list >>> To (un)subscribe, modify options or view archives go to: >>> http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe >>> Only members subscribed via the mailman list are allowed to post. >> >> >> >> -- >> Arnaud Spiwack >> Director, Research at https://moduscreate.com and https://tweag.io. >> _______________________________________________ >> Haskell-Cafe mailing list >> To (un)subscribe, modify options or view archives go to: >> http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe >> Only members subscribed via the mailman list are allowed to post. > > > > -- > Noon van der Silk, ن > > http://silky.github.io/ > > "My programming language is kindness." > -- Arnaud Spiwack Director, Research at https://moduscreate.com and https://tweag.io.

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[ANNOUNCE] GHC 9.8.1-alpha2 is now available
by Ben Gamari 22 Aug '23

22 Aug '23

The GHC developers are very pleased to announce the availability of the second alpha prerelease of GHC 9.8.1. Binary distributions, source distributions, and documentation are available at https://downloads.haskell.org/ghc/9.8.1-alpha2 GHC 9.8 will bring a number of new features and improvements, including: * Preliminary support the `TypeApplications` language extension [type-binders], allowing types to be bound in type declarations. * Support for the `ExtendedLiterals` extension, providing syntax for non-word-sized numeric literals in the surface language [extended-literals] * Improved rewrite rule matching behavior, allowing limited matching of higher-order patterns * Better support for user-defined warnings by way of the `WARNING` pragma [warnings] * The introduction of the new `GHC.TypeError.Unsatisfiable` constraint, allowing more predictable user-defined type errors [unsatisfiable] * Implementation of the export deprecation proposal, allowing module exports to be marked with `DEPRECATE` pragmas [deprecated-exports] * The addition of build semaphore support for parallel compilation; with coming support in `cabal-install` this will allow better use of parallelism in multi-package builds [jsem] * More efficient representation of info table provenance information, reducing binary sizes by over 50% in some cases when `-finfo-table-map` is in use A full accounting of changes can be found in the [release notes]. This alpha includes around two dozen bug-fixes relative to alpha 1. We would like to thank GitHub, IOG, the Zw3rk stake pool, Well-Typed, Tweag I/O, Serokell, Equinix, 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. Happy compiling, ~ Ben [type-binders]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0425-d… [extended-literals]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0451-s… [unsatisfiable]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0433-u… [warnings]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0541-w… [deprecated-exports]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0134-d… [jsem]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0540-j… [release notes]: https://downloads.haskell.org/ghc/9.8.1-alpha2/docs/users_guide/9.8.1-notes… [ticket]: https://gitlab.haskell.org/ghc/ghc/-/issues/new

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Weird pipeline failures
by Erdi, Gergo 22 Aug '23

22 Aug '23

PUBLIC Hi, On e.g. https://gitlab.haskell.org/ghc/ghc/-/commit/9b4fe2a39952b0a463bcf67f1b357b8… I am seeing very weird failures tagged "yaml invalid": Unable to create pipeline * 'test-primops-validate' job needs 'x86_64-linux-deb10-validate+debug_info' job, but 'x86_64-linux-deb10-validate+debug_info' is not in any previous stage * 'test-primops-validate' job needs 'x86_64-darwin-validate' job, but 'x86_64-darwin-validate' is not in any previous stage Is the CI setup experiencing some temporary hiccup, or is `master` broken? Thanks, Gergo This email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please delete all copies and notify the sender immediately. You may wish to refer to the incorporation details of Standard Chartered PLC, Standard Chartered Bank and their subsidiaries at https: //www.sc.com/en/our-locations Where you have a Financial Markets relationship with Standard Chartered PLC, Standard Chartered Bank and their subsidiaries (the "Group"), information on the regulatory standards we adhere to and how it may affect you can be found in our Regulatory Compliance Statement at https: //www.sc.com/rcs/ and Regulatory Compliance Disclosures at http: //www.sc.com/rcs/fm Insofar as this communication is not sent by the Global Research team and contains any market commentary, the market commentary has been prepared by the sales and/or trading desk of Standard Chartered Bank or its affiliate. It is not and does not constitute research material, independent research, recommendation or financial advice. Any market commentary is for information purpose only and shall not be relied on for any other purpose and is subject to the relevant disclaimers available at https: //www.sc.com/en/regulatory-disclosures/#market-disclaimer. Insofar as this communication is sent by the Global Research team and contains any research materials prepared by members of the team, the research material is for information purpose only and shall not be relied on for any other purpose, and is subject to the relevant disclaimers available at https: //research.sc.com/research/api/application/static/terms-and-conditions. Insofar as this e-mail contains the term sheet for a proposed transaction, by responding affirmatively to this e-mail, you agree that you have understood the terms and conditions in the attached term sheet and evaluated the merits and risks of the transaction. We may at times also request you to sign the term sheet to acknowledge the same. Please visit https: //www.sc.com/en/regulatory-disclosures/dodd-frank/ for important information with respect to derivative products.

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Problem building 9.4.7 on Fedora 36 (bytestring/cbits/is-valid-utf8.c)
by Viktor Dukhovni 15 Aug '23

15 Aug '23

The build was failing, because rts/OSThreads.h via Rts.h from libraries/bytestring/cbits/is-valid-utf8.c had no definition of `clockid_t`. This type is not exposed with _POSIX_C_SOURCE is not defined to a sufficiently high value: SYNOPSIS #include <time.h> int clock_getres(clockid_t clockid, struct timespec *res); int clock_gettime(clockid_t clockid, struct timespec *tp); int clock_settime(clockid_t clockid, const struct timespec *tp); Link with -lrt (only for glibc versions before 2.17). Feature Test Macro Requirements for glibc (see feature_test_macros(7)): clock_getres(), clock_gettime(), clock_settime(): _POSIX_C_SOURCE >= 199309L I quick-and-dirty work-around was: --- a/libraries/bytestring/cbits/is-valid-utf8.c +++ b/libraries/bytestring/cbits/is-valid-utf8.c @@ -27,6 +27,10 @@ LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ +#undef _POSIX_C_SOURCE +#define _POSIX_C_SOURCE 200809L +#undef _XOPEN_SOURCE +#define _XOPEN_SOURCE 700 #pragma GCC push_options #pragma GCC optimize("-O2") #include <stdbool.h> There's surely a better solution. -- Viktor.

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BoxedRep UNPACK pragma
by Alan & Kim Zimmerman 13 Aug '23

13 Aug '23

I have seen the following warning on master for some time compiler/GHC/Core/TyCon.hs:1540:5: warning: • Ignoring unusable UNPACK pragma on the first argument of ‘BoxedRep’ • In the definition of data constructor ‘BoxedRep’ In the data type declaration for ‘PrimRep’ | 1540 | | BoxedRep {-# UNPACK #-} !(Maybe Levity) -- ^ Boxed, heap value | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Is it something that needs to be fixed? Can the code be updated to remove the warning? Alan

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