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* Constraint simplification loop now depends on `ExpansionFuel`Apoorv Ingle2023-03-061-0/+3
| | | | | | | | | | | | | | instead of a boolean flag for `CDictCan.cc_pend_sc`. Pending givens get a fuel of 3 while Wanted and quantified constraints get a fuel of 1. This helps pending given constraints to keep up with pending wanted constraints in case of `UndecidableSuperClasses` and superclass expansions while simplifying the infered type. Adds 3 dynamic flags for controlling the fuels for each type of constraints `-fgivens-expansion-fuel` for givens `-fwanteds-expansion-fuel` for wanteds and `-fqcs-expansion-fuel` for quantified constraints Fixes #21909 Added Tests T21909, T21909b Added Note [Expanding Recursive Superclasses and ExpansionFuel]
* Fix typo in docs referring to threadLabelChris Wendt2023-03-041-1/+1
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* Export getSolo from Data.TupleDavid Feuer2023-03-031-0/+1
| | | | | | | Proposed in [CLC proposal #113](https://github.com/haskell/core-libraries-committee/issues/113) and [approved by the CLC](https://github.com/haskell/core-libraries-committee/issues/113#issuecomment-1452452191)
* Fix SCC grouping exampleTom Ellis2023-02-271-1/+1
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* Don't specialise incoherent instance applicationsGergő Érdi2023-02-271-0/+6
| | | | | | | | | | | | | | Using incoherent instances, there can be situations where two occurrences of the same overloaded function at the same type use two different instances (see #22448). For incoherently resolved instances, we must mark them with `nospec` to avoid the specialiser rewriting one to the other. This marking is done during the desugaring of the `WpEvApp` wrapper. Fixes #22448 Metric Increase: T15304
* rts: Fix `prompt#` when profiling is enabledAlexis King2023-02-231-0/+1
| | | | | | | | | This commit also adds a new -Dk RTS option to the debug RTS to assist debugging continuation captures. Currently, the printed information is quite minimal, but more can be added in the future if it proves to be useful when debugging future issues. fixes #23001
* fix: Update documentation linksromes2023-02-211-2/+2
| | | | | | | Closes #23008 Additionally batches some fixes to pointers to the Note [Wired-in units], and a typo in said note.
* ghc-prim: levity-polymorphic array equality opssheaf2023-02-211-0/+11
| | | | | | | | | This patch changes the pointer-equality comparison operations in GHC.Prim.PtrEq to work with arrays of unlifted values, e.g. sameArray# :: forall {l} (a :: TYPE (BoxedRep l)). Array# a -> Array# a -> Int# Fixes #22976
* GHC proposal 496 - Nullary record wildcardsGeorgi Lyubenov2023-02-211-0/+6
| | | | | | | | | | | | | | | | | | | This patch implements GHC proposal 496, which allows record wildcards to be used for nullary constructors, e.g. data A = MkA1 | MkA2 { fld1 :: Int } f :: A -> Int f (MkA1 {..}) = 0 f (MkA2 {..}) = fld1 To achieve this, we add arity information to the record field environment, so that we can accept a constructor which has no fields while continuing to reject non-record constructors with more than 1 field. See Note [Nullary constructors and empty record wildcards], as well as the more general overview in Note [Local constructor info in the renamer], both in the newly introduced GHC.Types.ConInfo module. Fixes #22161
* Merge libiserv with ghciSylvain Henry2023-02-172-2/+0
| | | | | | | | | | `libiserv` serves no purpose. As it depends on `ghci` and doesn't have more dependencies than the `ghci` package, its code could live in the `ghci` package too. This commit also moves most of the code from the `iserv` program into the `ghci` package as well so that it can be reused. This is especially useful for the implementation of TH for the JS backend (#22261, !9779).
* No default finalizer exception handlersheaf2023-02-161-4/+3
| | | | | | | | | | | | Commit cfc8e2e2 introduced a mechanism for handling of exceptions that occur during Handle finalization, and 372cf730 set the default handler to print out the error to stderr. However, #21680 pointed out we might not want to set this by default, as it might pollute users' terminals with unwanted information. So, for the time being, the default handler discards the exception. Fixes #21680
* docs: add a section for the wasm backendCheng Shao2023-02-162-1/+102
| | | | Fixes #22658
* Add -single-threaded flag to force single threaded rtsOleg Grenrus2023-02-151-0/+11
| | | | | This is the small part of implementing https://github.com/ghc-proposals/ghc-proposals/pull/240
* docs: release notes, user guide: add js backenddoyougnu2023-02-152-0/+39
| | | | Follow up from #21078
* Introduce warning for loopy superclass solvesheaf2023-02-142-1/+43
| | | | | | | | | | | | | | | | | Commit aed1974e completely re-engineered the treatment of loopy superclass dictionaries in instance declarations. Unfortunately, it has the potential to break (albeit in a rather minor way) user code. To alleviate migration concerns, this commit re-introduces the old behaviour. Any reliance on this old behaviour triggers a warning, controlled by `-Wloopy-superclass-solve`. The warning text explains that GHC might produce bottoming evidence, and provides a migration strategy. This allows us to provide a graceful migration period, alerting users when they are relying on this unsound behaviour. Fixes #22912 #22891 #20666 #22894 #22905
* Mention new `Foreign.Marshal.Pool` implementation in User's Guideamesgen2023-02-141-5/+3
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* Document that -fproc-alignment was introduced only in GHC 8.6Bodigrim2023-02-131-0/+2
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* docs: Add section about profiling and foreign callswip/profiling-docs-refreshMatthew Pickering2023-02-131-0/+36
| | | | | | | | | Previously there was no documentation for how foreign calls interacted with the profiler. This can be quite confusing for users so getting it into the user guide is the first step to a potentially better solution. See the ticket for more insightful discussion. Fixes #21764
* Refresh profiling docsMatthew Pickering2023-02-132-150/+57
| | | | | | | I went through the whole of the profiling docs and tried to amend them to reflect current best practices and tooling. In particular I removed some old references to tools such as hp2any and replaced them with references to eventlog2html.
* Don't allow . in overloaded labelssheaf2023-02-071-1/+1
| | | | | | | | | | This patch removes . from the list of allowed characters in a non-quoted overloaded label, as it was realised this steals syntax, e.g. (#.). Users who want this functionality will have to add quotes around the label, e.g. `#"17.28"`. Fixes #22821
* Remove extraneous word in Roles user guideJan Hrček2023-02-061-1/+1
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* docs: 9.6 release notes for wasm backendCheng Shao2023-02-021-0/+16
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* compiler: Implement higher order patterns in the rule matcherJaro Reinders2023-02-022-1/+35
| | | | | | | | This implements proposal 555 and closes ticket #22465. See the proposal and ticket for motivation. The core changes of this patch are in the GHC.Core.Rules.match function and they are explained in the Note [Matching higher order patterns].
* User's guide: Clarify overlapping instance candidate eliminationJason Shipman2023-01-301-2/+2
| | | | | | | | | | | | This commit updates the user's guide section on overlapping instance candidate elimination to use "or" verbiage instead of "either/or" in regards to the current pair of candidates' being overlappable or overlapping. "Either IX is overlappable, or IY is overlapping" can cause confusion as it suggests "Either IX is overlappable, or IY is overlapping, but not both". This was initially discussed on this Discourse topic: https://discourse.haskell.org/t/clarification-on-overlapping-instance-candidate-elimination/5677
* nativeGen: Disable asm-shortcutting on DarwinBen Gamari2023-01-301-2/+4
| | | | | | | | | | | | | Asm-shortcutting may produce relative references to symbols defined in other compilation units. This is not something that MachO relocations support (see #21972). For this reason we disable the optimisation on Darwin. We do so without a warning since this flag is enabled by `-O2`. Another way to address this issue would be to rather implement a PLT-relocatable jump-table strategy. However, this would only benefit Darwin and does not seem worth the effort. Closes #21972.
* CApiFFI: add ConstPtr for encoding const-qualified pointer return typesnineonine2023-01-282-0/+15
| | | | | | | | | | | | | Previously, when using `capi` calling convention in foreign declarations, code generator failed to handle const-cualified pointer return types. This resulted in CC toolchain throwing `-Wincompatible-pointer-types-discards-qualifiers` warning. `Foreign.C.Types.ConstPtr` newtype was introduced to handle these cases - special treatment was put in place to generate appropritetly qualified C wrapper that no longer triggers the above mentioned warning. Fixes #22043.
* Revert "CApiFFI: add ConstPtr for encoding const-qualified pointer return ↵Ben Gamari2023-01-282-15/+0
| | | | | | types (#22043)" This reverts commit 99aca26b652603bc62953157a48e419f737d352d.
* Allow waiting for timerfd to be interrupted during rts shutdownWander Hillen2023-01-241-1/+71
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* Clarify where `f` is definedTom Ellis2023-01-241-4/+7
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* Set "since: 9.8" for TypeAbstractions and -Wterm-variable-captureVladislav Zavialov2023-01-235-7/+17
| | | | | These flags did not make it into the 9.6 release series, so the "since" annotations must be corrected.
* Move documentation of deferred type error flags out of warnings sectionAdam Gundry2023-01-182-62/+63
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* Revise warnings documentation in user's guideAdam Gundry2023-01-182-34/+60
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* Enable -Wstar-is-type by default (#22759)Vladislav Zavialov2023-01-182-4/+3
| | | | | | | | | | | | | Following the plan in GHC Proposal #143 "Remove the * kind syntax", which states: In the next release (or 3 years in), enable -fwarn-star-is-type by default. The "next release" happens to be 9.6.1 I also moved the T21583 test case from should_fail to should_compile, because the only reason it was failing was -Werror=compat in our test suite configuration.
* Document the semantics of pattern bindings a bit betterSimon Peyton Jones2023-01-172-67/+163
| | | | This MR is in response to the discussion on #22719
* Only gc sparks locally when we can ensure marking is done.Andreas Klebinger2023-01-121-3/+6
| | | | | | | | When performing GC without work stealing there was no guarantee that spark pruning was happening after marking of the sparks. This could cause us to GC live sparks under certain circumstances. Fixes #22528.
* Refactor the treatment of loopy superclass dictswip/T20666Richard Eisenberg2023-01-111-10/+94
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch completely re-engineers how we deal with loopy superclass dictionaries in instance declarations. It fixes #20666 and #19690 The highlights are * Recognise that the loopy-superclass business should use precisely the Paterson conditions. This is much much nicer. See Note [Recursive superclasses] in GHC.Tc.TyCl.Instance * With that in mind, define "Paterson-smaller" in Note [Paterson conditions] in GHC.Tc.Validity, and the new data type `PatersonSize` in GHC.Tc.Utils.TcType, along with functions to compute and compare PatsonSizes * Use the new PatersonSize stuff when solving superclass constraints See Note [Solving superclass constraints] in GHC.Tc.TyCl.Instance * In GHC.Tc.Solver.Monad.lookupInInerts, add a missing call to prohibitedSuperClassSolve. This was the original cause of #20666. * Treat (TypeError "stuff") as having PatersonSize zero. See Note [Paterson size for type family applications] in GHC.Tc.Utils.TcType. * Treat the head of a Wanted quantified constraint in the same way as the superclass of an instance decl; this is what fixes #19690. See GHC.Tc.Solver.Canonical Note [Solving a Wanted forall-constraint] (Thanks to Matthew Craven for this insight.) This entailed refactoring the GivenSc constructor of CtOrigin a bit, to say whether it comes from an instance decl or quantified constraint. * Some refactoring way in which redundant constraints are reported; we don't want to complain about the extra, apparently-redundant constraints that we must add to an instance decl because of the loopy-superclass thing. I moved some work from GHC.Tc.Errors to GHC.Tc.Solver. * Add a new section to the user manual to describe the loopy superclass issue and what rules it follows.
* Introduce the TypeAbstractions language flagVladislav Zavialov2023-01-114-80/+99
| | | | | | | | | | | | | | | | | | | | | | | | | GHC Proposals #448 "Modern scoped type variables" and #425 "Invisible binders in type declarations" introduce a new language extension flag: TypeAbstractions. Part of the functionality guarded by this flag has already been implemented, namely type abstractions in constructor patterns, but it was guarded by a combination of TypeApplications and ScopedTypeVariables instead of a dedicated language extension flag. This patch does the following: * introduces a new language extension flag TypeAbstractions * requires TypeAbstractions for @a-syntax in constructor patterns instead of TypeApplications and ScopedTypeVariables * creates a User's Guide page for TypeAbstractions and moves the "Type Applications in Patterns" section there To avoid a breaking change, the new flag is implied by ScopedTypeVariables and is retroactively added to GHC2021. Metric Decrease: MultiLayerModulesTH_OneShot
* Added a new warning about compatibility with RequiredTypeArgumentsHaskellMouse2023-01-112-0/+26
| | | | | | | | | This commit introduces a new warning that indicates code incompatible with future extension: RequiredTypeArguments. Enabling this extension may break some code and the warning will help to make it compatible in advance.
* Misc cleanupKrzysztof Gogolewski2023-01-052-2/+5
| | | | | | | | | - Remove unused uniques and hs-boot declarations - Fix types of seq and unsafeCoerce# - Remove FastString/String roundtrip in JS - Use TTG to enforce totality - Remove enumeration in Heap/Inspect; the 'otherwise' clause serves the primitive types well.
* sphinx: Use modern syntax for extlinksMatthew Pickering2023-01-041-2/+2
| | | | | | | | | | | | | | | | | | | | | | This fixes the following build error: ``` Command line: /opt/homebrew/opt/sphinx-doc/bin/sphinx-build -b man -d /private/tmp/extra-dir-55768274273/.doctrees-man -n -w /private/tmp/extra-dir-55768274273/.log docs/users_guide /private/tmp/extra-dir-55768274273 ===> Command failed with error code: 2 Exception occurred: File "/opt/homebrew/Cellar/sphinx-doc/6.0.0/libexec/lib/python3.11/site-packages/sphinx/ext/extlinks.py", line 101, in role title = caption % part ~~~~~~~~^~~~~~ TypeError: not all arguments converted during string formatting ``` I tested on Sphinx-5.1.1 and Sphinx-6.0.0 Thanks for sterni for providing instructions about how to test using sphinx-6.0.0. Fixes #22690
* compiler: Add -f[no-]split-sections flagsMatthew Pickering2023-01-041-1/+3
| | | | | | | | Here we add a `-fsplit-sections` flag which may some day replace `-split-sections`. This has the advantage of automatically providing a `-fno-split-sections` flag, which is useful for our packaging because we enable `-split-sections` by default but want to disable it in certain configurations.
* Drop support for kind constraints.wip/p547Richard Eisenberg2022-12-241-34/+2
| | | | | | | | | | | | | | | | | | | | | | | | This implements proposal 547 and closes ticket #22298. See the proposal and ticket for motivation. Compiler perf improves a bit Metrics: compile_time/bytes allocated ------------------------------------- CoOpt_Singletons(normal) -2.4% GOOD T12545(normal) +1.0% T13035(normal) -13.5% GOOD T18478(normal) +0.9% T9872d(normal) -2.2% GOOD geo. mean -0.2% minimum -13.5% maximum +1.0% Metric Decrease: CoOpt_Singletons T13035 T9872d
* codeGen: Introduce ThreadSanitizer instrumentationBen Gamari2022-12-151-0/+16
| | | | | | This introduces a new Cmm pass which instruments the program with ThreadSanitizer annotations, allowing full tracking of mutator memory accesses via TSAN.
* Fix #22300 Document GHC's extensions to valid whitespaceMike Pilgrem2022-12-092-0/+30
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* Document TH splices' interaction with INCOHERENT instancesRyan Scott2022-12-091-0/+72
| | | | | | | | | Top-level declaration splices can having surprising interactions with `INCOHERENT` instances, as observed in #22492. This patch resolves #22492 by documenting this strange interaction in the GHC User's Guide. [ci skip]
* Properly cast values when writing/reading unboxed sums.Andreas Klebinger2022-11-301-0/+10
| | | | | | | Unboxed sums might store a Int8# value as Int64#. This patch makes sure we keep track of the actual value type. See Note [Casting slot arguments] for the details.
* Add Javascript backendSylvain Henry2022-11-291-0/+6
| | | | | | | | | | | | | | | Add JS backend adapted from the GHCJS project by Luite Stegeman. Some features haven't been ported or implemented yet. Tests for these features have been disabled with an associated gitlab ticket. Bump array submodule Work funded by IOG. Co-authored-by: Jeffrey Young <jeffrey.young@iohk.io> Co-authored-by: Luite Stegeman <stegeman@gmail.com> Co-authored-by: Josh Meredith <joshmeredith2008@gmail.com>
* Print unticked promoted data constructors (#20531)Vladislav Zavialov2022-11-251-0/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before this patch, GHC unconditionally printed ticks before promoted data constructors: ghci> type T = True -- unticked (user-written) ghci> :kind! T T :: Bool = 'True -- ticked (compiler output) After this patch, GHC prints ticks only when necessary: ghci> type F = False -- unticked (user-written) ghci> :kind! F F :: Bool = False -- unticked (compiler output) ghci> data False -- introduce ambiguity ghci> :kind! F F :: Bool = 'False -- ticked by necessity (compiler output) The old behavior can be enabled by -fprint-redundant-promotion-ticks. Summary of changes: * Rename PrintUnqualified to NamePprCtx * Add QueryPromotionTick to it * Consult the GlobalRdrEnv to decide whether to print a tick (see mkPromTick) * Introduce -fprint-redundant-promotion-ticks Co-authored-by: Artyom Kuznetsov <hi@wzrd.ht>
* CApiFFI: add ConstPtr for encoding const-qualified pointer return types (#22043)nineonine2022-11-232-0/+15
| | | | | | | | | | | | | Previously, when using `capi` calling convention in foreign declarations, code generator failed to handle const-cualified pointer return types. This resulted in CC toolchain throwing `-Wincompatible-pointer-types-discards-qualifiers` warning. `Foreign.C.Types.ConstPtr` newtype was introduced to handle these cases - special treatment was put in place to generate appropritetly qualified C wrapper that no longer triggers the above mentioned warning. Fixes #22043
* Add documentation on custom Prelude modules (#22228)Lawton Nichols2022-11-231-3/+42
| | | | Specifically, custom Prelude modules that are named `Prelude`.
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