summaryrefslogtreecommitdiff
path: root/compiler/GHC/Tc
Commit message (Collapse)AuthorAgeFilesLines
* Drop support for kind constraints.wip/p547Richard Eisenberg2022-12-249-114/+71
| | | | | | | | | | | | | | | | | | | | | | | | 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
* Store RdrName rather than OccName in HolesMatthew Pickering2022-12-246-15/+17
| | | | | | | | | | | | | | | | | In #20472 it was pointed out that you couldn't defer out of scope but the implementation collapsed a RdrName into an OccName to stuff it into a Hole. This leads to the error message for a deferred qualified name dropping the qualification which affects the quality of the error message. This commit adds a bit more structure to a hole, so a hole can replace a RdrName without losing information about what that RdrName was. This is important when printing error messages. I also added a test which checks the Template Haskell deferral of out of scope qualified names works properly. Fixes #22130
* Fix an assertion check in addToEqualCtListSimon Peyton Jones2022-12-211-9/+17
| | | | | | | The old assertion saw that a constraint ct could rewrite itself (of course it can) and complained (stupid). Fixes #22645
* checkValidInst: Don't expand synonyms when splitting sigma typesRyan Scott2022-12-151-2/+29
| | | | | | | | | | | | | | | Previously, the `checkValidInst` function (used when checking that an instance declaration is headed by an actual type class, not a type synonym) was using `tcSplitSigmaTy` to split apart the `forall`s and instance context. This is incorrect, however, as `tcSplitSigmaTy` expands type synonyms, which can cause instances headed by quantified constraint type synonyms to be accepted erroneously. This patch introduces `splitInstTyForValidity`, a variant of `tcSplitSigmaTy` specialized for validity checking that does _not_ expand type synonyms, and uses it in `checkValidInst`. Fixes #22570.
* Typeable: Fix module locations of some definitions in GHC.TypesMatthew Pickering2022-12-081-4/+17
| | | | | | | | | | | | | There was some confusion in Data.Typeable about which module certain wired-in things were defined in. Just because something is wired-in doesn't mean it comes from GHC.Prim, in particular things like LiftedRep and RuntimeRep are defined in GHC.Types and that's the end of the story. Things like Int#, Float# etc are defined in GHC.Prim as they have no Haskell definition site at all so we need to generate type representations for them (which live in GHC.Types). Fixes #22510
* backpack: Be more careful when adding together ImportAvailsMatthew Pickering2022-12-081-9/+21
| | | | | | | | | | | | | | There was some code in the signature merging logic which added together the ImportAvails of the signature and the signature which was merged into it. This had the side-effect of making the merged signature depend on the signature (via a normal module dependency). The intention was to propagate orphan instances through the merge but this also messed up recompilation logic because we shouldn't be attempting to load B.hi when mergeing it. The fix is to just combine the part of ImportAvails that we intended to (transitive info, orphan instances and type family instances) rather than the whole thing.
* Handle type data declarations in Template Haskell quotations and splices ↵Ross Paterson2022-12-031-1/+1
| | | | | | | (fixes #22500) This adds a TypeDataD constructor to the Template Haskell Dec type, and ensures that the constructors it contains go in the TyCls namespace.
* Add special case for :Main module in `GHC.IfaceToCore.mk_top_id`Matthew Pickering2022-12-021-0/+8
| | | | | | | | | | | | | | See Note [Root-main Id] The `:Main` special binding is actually defined in the current module (hence don't go looking for it externally) but the module name is rOOT_MAIN rather than the current module so we need this special case. There was already some similar logic in `GHC.Rename.Env` for External Core, but now the "External Core" is in interface files it needs to be moved here instead. Fixes #22405
* Refactor TyCon to have a top-level productSimon Peyton Jones2022-12-023-5/+4
| | | | | | | | | | | This patch changes the representation of TyCon so that it has a top-level product type, with a field that gives the details (newtype, type family etc), #22458. Not much change in allocation, but execution seems to be a bit faster. Includes a change to the haddock submodule to adjust for API changes.
* Use mkNakedFunTy in tcPatSynSigSimon Peyton Jones2022-11-301-3/+12
| | | | | | | | | | As #22521 showed, in tcPatSynSig we make a "fake type" to kind-generalise; and that type has unzonked type variables in it. So we must not use `mkFunTy` (which checks FunTy's invariants) via `mkPhiTy` when building this type. Instead we need to use `mkNakedFunTy`. Easy fix.
* Be more careful in GHC.Tc.Solver.Interact.solveOneFromTheOtherSimon Peyton Jones2022-11-304-56/+70
| | | | | | | | We were failing to account for the cc_pend_sc flag in this important function, with the result that we expanded superclasses forever. Fixes #22516.
* Add Javascript backendSylvain Henry2022-11-292-1/+5
| | | | | | | | | | | | | | | 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>
* Killing cc_fundeps, streamlining kind equality orientation, and type ↵Apoorv Ingle2022-11-294-100/+251
| | | | | | | | | | | | | | | | | | | | equality processing order Fixes: #217093 Associated to #19415 This change * Flips the orientation of the the generated kind equality coercion in canEqLHSHetero; * Removes `cc_fundeps` in CDictCan as the check was incomplete; * Changes `canDecomposableTyConAppOk` to ensure we process kind equalities before type equalities and avoiding a call to `canEqLHSHetero` while processing wanted TyConApp equalities * Adds 2 new tests for validating the change - testsuites/typecheck/should_compile/T21703.hs and - testsuites/typecheck/should_fail/T19415b.hs (a simpler version of T19415.hs) * Misc: Due to the change in the equality direction some error messages now have flipped type mismatch errors * Changes in Notes: - Note [Fundeps with instances, and equality orientation] supercedes Note [Fundeps with instances] - Added Note [Kind Equality Orientation] to visualize the kind flipping - Added Note [Decomposing Dependent TyCons and Processing Wanted Equalties]
* Fix decomposition of TyConAppswip/T22331Simon Peyton Jones2022-11-253-219/+320
| | | | | | | | | | | | | | | | Ticket #22331 showed that we were being too eager to decompose a Wanted TyConApp, leading to incompleteness in the solver. To understand all this I ended up doing a substantial rewrite of the old Note [Decomposing equalities], now reborn as Note [Decomposing TyConApp equalities]. Plus rewrites of other related Notes. The actual fix is very minor and actually simplifies the code: in `can_decompose` in `GHC.Tc.Solver.Canonical.canTyConApp`, we now call `noMatchableIrreds`. A closely related refactor: we stop trying to use the same "no matchable givens" function here as in `matchClassInst`. Instead split into two much simpler functions.
* Print unticked promoted data constructors (#20531)Vladislav Zavialov2022-11-251-16/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Convert diagnostics in GHC.Rename.Expr to proper TcRnMessage (#20115)Andrei Borzenkov2022-11-242-0/+250
| | | | | | | | | | | | | | | | | | | | Problem: avoid usage of TcRnMessageUnknown Solution: The following `TcRnMessage` messages has been introduced: TcRnNoRebindableSyntaxRecordDot TcRnNoFieldPunsRecordDot TcRnIllegalStaticExpression TcRnIllegalStaticFormInSplice TcRnListComprehensionDuplicateBinding TcRnEmptyStmtsGroup TcRnLastStmtNotExpr TcRnUnexpectedStatementInContext TcRnIllegalTupleSection TcRnIllegalImplicitParameterBindings TcRnSectionWithoutParentheses Co-authored-by: sheaf <sam.derbyshire@gmail.com>
* Scrub some no-warning pragmas.M Farkas-Dyck2022-11-2316-42/+10
|
* Buglet in GHC.Tc.Module.checkBootTyConSimon Peyton Jones2022-11-201-2/+6
| | | | | | | | This lurking bug used the wrong function to compare two types in GHC.Tc.Module.checkBootTyCon It's hard to trigger the bug, which only came up during !9343, so there's no regression test in this MR.
* Be more careful when reporting unbound RULE bindersSimon Peyton Jones2022-11-191-1/+2
| | | | | | See Note [Variables unbound on the LHS] in GHC.HsToCore.Binds. Fixes #22471.
* Misc cleanupKrzysztof Gogolewski2022-11-161-1/+1
| | | | | | | * Replace catMaybes . map f with mapMaybe f * Use concatFS to concatenate multiple FastStrings * Fix documentation of -exclude-module * Cleanup getIgnoreCount in GHCi.UI
* Type vs Constraint: finally nailedSimon Peyton Jones2022-11-1150-1371/+1237
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This big patch addresses the rats-nest of issues that have plagued us for years, about the relationship between Type and Constraint. See #11715/#21623. The main payload of the patch is: * To introduce CONSTRAINT :: RuntimeRep -> Type * To make TYPE and CONSTRAINT distinct throughout the compiler Two overview Notes in GHC.Builtin.Types.Prim * Note [TYPE and CONSTRAINT] * Note [Type and Constraint are not apart] This is the main complication. The specifics * New primitive types (GHC.Builtin.Types.Prim) - CONSTRAINT - ctArrowTyCon (=>) - tcArrowTyCon (-=>) - ccArrowTyCon (==>) - funTyCon FUN -- Not new See Note [Function type constructors and FunTy] and Note [TYPE and CONSTRAINT] * GHC.Builtin.Types: - New type Constraint = CONSTRAINT LiftedRep - I also stopped nonEmptyTyCon being built-in; it only needs to be wired-in * Exploit the fact that Type and Constraint are distinct throughout GHC - Get rid of tcView in favour of coreView. - Many tcXX functions become XX functions. e.g. tcGetCastedTyVar --> getCastedTyVar * Kill off Note [ForAllTy and typechecker equality], in (old) GHC.Tc.Solver.Canonical. It said that typechecker-equality should ignore the specified/inferred distinction when comparein two ForAllTys. But that wsa only weakly supported and (worse) implies that we need a separate typechecker equality, different from core equality. No no no. * GHC.Core.TyCon: kill off FunTyCon in data TyCon. There was no need for it, and anyway now we have four of them! * GHC.Core.TyCo.Rep: add two FunTyFlags to FunCo See Note [FunCo] in that module. * GHC.Core.Type. Lots and lots of changes driven by adding CONSTRAINT. The key new function is sORTKind_maybe; most other changes are built on top of that. See also `funTyConAppTy_maybe` and `tyConAppFun_maybe`. * Fix a longstanding bug in GHC.Core.Type.typeKind, and Core Lint, in kinding ForAllTys. See new tules (FORALL1) and (FORALL2) in GHC.Core.Type. (The bug was that before (forall (cv::t1 ~# t2). blah), where blah::TYPE IntRep, would get kind (TYPE IntRep), but it should be (TYPE LiftedRep). See Note [Kinding rules for types] in GHC.Core.Type. * GHC.Core.TyCo.Compare is a new module in which we do eqType and cmpType. Of course, no tcEqType any more. * GHC.Core.TyCo.FVs. I moved some free-var-like function into this module: tyConsOfType, visVarsOfType, and occCheckExpand. Refactoring only. * GHC.Builtin.Types. Compiletely re-engineer boxingDataCon_maybe to have one for each /RuntimeRep/, rather than one for each /Type/. This dramatically widens the range of types we can auto-box. See Note [Boxing constructors] in GHC.Builtin.Types The boxing types themselves are declared in library ghc-prim:GHC.Types. GHC.Core.Make. Re-engineer the treatment of "big" tuples (mkBigCoreVarTup etc) GHC.Core.Make, so that it auto-boxes unboxed values and (crucially) types of kind Constraint. That allows the desugaring for arrows to work; it gathers up free variables (including dictionaries) into tuples. See Note [Big tuples] in GHC.Core.Make. There is still work to do here: #22336. But things are better than before. * GHC.Core.Make. We need two absent-error Ids, aBSENT_ERROR_ID for types of kind Type, and aBSENT_CONSTRAINT_ERROR_ID for vaues of kind Constraint. Ditto noInlineId vs noInlieConstraintId in GHC.Types.Id.Make; see Note [inlineId magic]. * GHC.Core.TyCo.Rep. Completely refactor the NthCo coercion. It is now called SelCo, and its fields are much more descriptive than the single Int we used to have. A great improvement. See Note [SelCo] in GHC.Core.TyCo.Rep. * GHC.Core.RoughMap.roughMatchTyConName. Collapse TYPE and CONSTRAINT to a single TyCon, so that the rough-map does not distinguish them. * GHC.Core.DataCon - Mainly just improve documentation * Some significant renamings: GHC.Core.Multiplicity: Many --> ManyTy (easier to grep for) One --> OneTy GHC.Core.TyCo.Rep TyCoBinder --> GHC.Core.Var.PiTyBinder GHC.Core.Var TyCoVarBinder --> ForAllTyBinder AnonArgFlag --> FunTyFlag ArgFlag --> ForAllTyFlag GHC.Core.TyCon TyConTyCoBinder --> TyConPiTyBinder Many functions are renamed in consequence e.g. isinvisibleArgFlag becomes isInvisibleForAllTyFlag, etc * I refactored FunTyFlag (was AnonArgFlag) into a simple, flat data type data FunTyFlag = FTF_T_T -- (->) Type -> Type | FTF_T_C -- (-=>) Type -> Constraint | FTF_C_T -- (=>) Constraint -> Type | FTF_C_C -- (==>) Constraint -> Constraint * GHC.Tc.Errors.Ppr. Some significant refactoring in the TypeEqMisMatch case of pprMismatchMsg. * I made the tyConUnique field of TyCon strict, because I saw code with lots of silly eval's. That revealed that GHC.Settings.Constants.mAX_SUM_SIZE can only be 63, because we pack the sum tag into a 6-bit field. (Lurking bug squashed.) Fixes * #21530 Updates haddock submodule slightly. Performance changes ~~~~~~~~~~~~~~~~~~~ I was worried that compile times would get worse, but after some careful profiling we are down to a geometric mean 0.1% increase in allocation (in perf/compiler). That seems fine. There is a big runtime improvement in T10359 Metric Decrease: LargeRecord MultiLayerModulesTH_OneShot T13386 T13719 Metric Increase: T8095
* Use TcRnDiagnostic in GHC.Tc.TyCl.Instance (#20117)Giles Anderson2022-11-093-48/+151
| | | | | | | | | | | | The following `TcRnDiagnostic` messages have been introduced: TcRnWarnUnsatisfiedMinimalDefinition TcRnMisplacedInstSig TcRnBadBootFamInstDeclErr TcRnIllegalFamilyInstance TcRnAssocInClassErr TcRnBadFamInstDecl TcRnNotOpenFamily
* Fix TypeData issues (fixes #22315 and #22332)Ross Paterson2022-11-083-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | There were two bugs here: 1. Treating type-level constructors as PromotedDataCon doesn't always work, in particular because constructors promoted via DataKinds are called both T and 'T. (Tests T22332a, T22332b, T22315a, T22315b) Fix: guard these cases with isDataKindsPromotedDataCon. 2. Type-level constructors were sent to the code generator, producing things like constructor wrappers. (Tests T22332a, T22332b) Fix: test for them in isDataTyCon. Other changes: * changed the marking of "type data" DataCon's as suggested by SPJ. * added a test TDGADT for a type-level GADT. * comment tweaks * change tcIfaceTyCon to ignore IfaceTyConInfo, so that IfaceTyConInfo is used only for pretty printing, not for typechecking. (SPJ)
* Define `Infinite` list and use where appropriate.M Farkas-Dyck2022-11-085-21/+24
| | | | | | | | Also add perf test for infinite list fusion. In particular, in `GHC.Core`, often we deal with infinite lists of roles. Also in a few locations we deal with infinite lists of names. Thanks to simonpj for helping to write the Note [Fusion for `Infinite` lists].
* Minor refactor around FastStringsKrzysztof Gogolewski2022-11-056-11/+14
| | | | | | | Pass FastStrings to functions directly, to make sure the rule for fsLit "literal" fires. Remove SDoc indirection in GHCi.UI.Tags and GHC.Unit.Module.Graph.
* Export pprTrace and friends from GHC.Prelude.Andreas Klebinger2022-11-033-3/+0
| | | | | Introduces GHC.Prelude.Basic which can be used in modules which are a dependency of the ppr code.
* Add accurate skolem info when quantifyingSimon Peyton Jones2022-11-014-62/+74
| | | | | | | Ticket #22379 revealed that skolemiseQuantifiedTyVar was dropping the passed-in skol_info on the floor when it encountered a SkolemTv. Bad! Several TyCons thereby share a single SkolemInfo on their binders, which lead to bogus error reports.
* Minor SDoc-related cleanupKrzysztof Gogolewski2022-10-282-21/+18
| | | | | | | | | | | * Rename pprCLabel to pprCLabelStyle, and use the name pprCLabel for a function using CStyle (analogous to pprAsmLabel) * Move LabelStyle to the CLabel module, it no longer needs to be in Outputable. * Move calls to 'text' right next to literals, to make sure the text/str rule is triggered. * Remove FastString/String roundtrip in Tc.Deriv.Generate * Introduce showSDocForUser', which abstracts over a pattern in GHCi.UI
* Use TcRnVDQInTermType in noNestedForallsContextsErr (#20115)Vladislav Zavialov2022-10-263-9/+19
| | | | | | | | | | | | | | | | | | | | | When faced with VDQ in the type of a term, GHC generates the following error message: Illegal visible, dependent quantification in the type of a term (GHC does not yet support this) Prior to this patch, there were two ways this message could have been generated and represented: 1. with the dedicated constructor TcRnVDQInTermType (see check_type in GHC.Tc.Validity) 2. with the transitional constructor TcRnUnknownMessage (see noNestedForallsContextsErr in GHC.Rename.Utils) Not only this led to duplication of code generating the final SDoc, it also made it tricky to track the origin of the error message. This patch fixes the problem by using TcRnVDQInTermType exclusively.
* Introduce TcRnWithHsDocContext (#22346)Vladislav Zavialov2022-10-263-15/+22
| | | | | | | | | | | | | | | | | Before this patch, GHC used withHsDocContext to attach an HsDocContext to an error message: addErr $ mkTcRnUnknownMessage $ mkPlainError noHints (withHsDocContext ctxt msg) The problem with this approach is that it only works with TcRnUnknownMessage. But could we attach an HsDocContext to a structured error message in a generic way? This patch solves the problem by introducing a new constructor to TcRnMessage: data TcRnMessage where ... TcRnWithHsDocContext :: !HsDocContext -> !TcRnMessage -> TcRnMessage ...
* Cleanup String/FastString conversionsKrzysztof Gogolewski2022-10-251-4/+4
| | | | | | | Remove unused mkPtrString and isUnderscoreFS. We no longer use mkPtrString since 1d03d8bef96. Remove unnecessary conversions between FastString and String and back.
* Convert Diagnostics in GHC.Tc.Gen.Splice (#20116)Aaron Allen2022-10-245-79/+538
| | | | | | | Replaces uses of `TcRnUnknownMessage` in `GHC.Tc.Gen.Splice` with structured diagnostics. closes #20116
* TyEq:N assertion: only for saturated applicationssheaf2022-10-192-6/+17
| | | | | | | | | | The assertion that checked TyEq:N in canEqCanLHSFinish incorrectly triggered in the case of an unsaturated newtype TyCon heading the RHS, even though we can't unwrap such an application. Now, we only trigger an assertion failure in case of a saturated application of a newtype TyCon. Fixes #22310
* Rename unsafeOverlap_matches -> unsafeOverlap_match in UnsafeOverlapsheaf2022-10-193-6/+4
|
* More precise types for fields of OverlappingInstances and UnsafeOverlap in ↵Bodigrim2022-10-193-34/+23
| | | | | | | | | | TcSolverReportMsg It's clear from asserts in `GHC.Tc.Errors` that `overlappingInstances_matches` and `unsafeOverlapped` are supposed to be non-empty, and `unsafeOverlap_matches` contains a single instance, but these invariants are immediately lost afterwards and not encoded in types. This patch enforces the invariants by pattern matching and makes types more precise, avoiding asserts and partial functions such as `head`.
* Enforce invariant of `ListBag` constructor.M Farkas-Dyck2022-10-191-2/+2
|
* Scrub various partiality involving lists (again).M Farkas-Dyck2022-10-196-26/+29
| | | | Lets us avoid some use of `head` and `tail`, and some panics.
* Add -fsuppress-error-contexts to disable printing error contexts in errorswip/diagnostics-configMatthew Pickering2022-10-181-5/+16
| | | | | | | | | | | | | In many development environments, the source span is the primary means of seeing what an error message relates to, and the In the expression: and In an equation for: clauses are not particularly relevant. However, they can grow to be quite long, which can make the message itself both feel overwhelming and interact badly with limited-space areas. It's simple to implement this flag so we might as well do it and give the user control about how they see their messages. Fixes #21722
* Allow configuration of error message printingMatthew Pickering2022-10-186-22/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This MR implements the idea of #21731 that the printing of a diagnostic method should be configurable at the printing time. The interface of the `Diagnostic` class is modified from: ``` class Diagnostic a where diagnosticMessage :: a -> DecoratedSDoc diagnosticReason :: a -> DiagnosticReason diagnosticHints :: a -> [GhcHint] ``` to ``` class Diagnostic a where type DiagnosticOpts a defaultDiagnosticOpts :: DiagnosticOpts a diagnosticMessage :: DiagnosticOpts a -> a -> DecoratedSDoc diagnosticReason :: a -> DiagnosticReason diagnosticHints :: a -> [GhcHint] ``` and so each `Diagnostic` can implement their own configuration record which can then be supplied by a client in order to dictate how to print out the error message. At the moment this only allows us to implement #21722 nicely but in future it is more natural to separate the configuration of how much information we put into an error message and how much we decide to print out of it. Updates Haddock submodule
* Clearer error msg for newtype GADTs with defaulted kindFinley McIlwaine2022-10-133-41/+97
| | | | | | | | | | | When a newtype introduces GADT eq_specs due to a defaulted RuntimeRep, we detect this and print the error message with explicit kinds. This also refactors newtype type checking to use the new diagnostic infra. Fixes #21447
* Export symbolSing, SSymbol, and friends (CLC#85)wip/clc-85Ryan Scott2022-10-061-4/+4
| | | | | | | | | | | | | | | This implements this Core Libraries Proposal: https://github.com/haskell/core-libraries-committee/issues/85 In particular, it: 1. Exposes the `symbolSing` method of `KnownSymbol`, 2. Exports the abstract `SSymbol` type used in `symbolSing`, and 3. Defines an API for interacting with `SSymbol`. This also makes corresponding changes for `natSing`/`KnownNat`/`SNat` and `charSing`/`KnownChar`/`SChar`. This fixes #15183 and addresses part (2) of #21568.
* Scrub various partiality involving empty lists.M Farkas-Dyck2022-09-301-16/+17
| | | | Avoids some uses of `head` and `tail`, and some panics when an argument is null.
* Avoid Data.List.group; prefer Data.List.NonEmpty.groupBodigrim2022-09-281-2/+3
| | | | | This allows to avoid further partiality, e. g., map head . group is replaced by map NE.head . NE.group, and there are less panic calls.
* Refactor UnfoldingSource and IfaceUnfoldingSimon Peyton Jones2022-09-281-2/+2
| | | | | | | | | | | | | | | | | | | | | | I finally got tired of the way that IfaceUnfolding reflected a previous structure of unfoldings, not the current one. This MR refactors UnfoldingSource and IfaceUnfolding to be simpler and more consistent. It's largely just a refactor, but in UnfoldingSource (which moves to GHC.Types.Basic, since it is now used in IfaceSyn too), I distinguish between /user-specified/ and /system-generated/ stable unfoldings. data UnfoldingSource = VanillaSrc | StableUserSrc -- From a user-specified pragma | StableSystemSrc -- From a system-generated unfolding | CompulsorySrc This has a minor effect in CSE (see the use of isisStableUserUnfolding in GHC.Core.Opt.CSE), which I tripped over when working on specialisation, but it seems like a Good Thing to know anyway.
* matchLocalInst: do domination analysissheaf2022-09-284-90/+219
| | | | | | | | | | | | | | | | | | | | | | | | | | When multiple Given quantified constraints match a Wanted, and there is a quantified constraint that dominates all others, we now pick it to solve the Wanted. See Note [Use only the best matching quantified constraint]. For example: [G] d1: forall a b. ( Eq a, Num b, C a b ) => D a b [G] d2: forall a . C a Int => D a Int [W] {w}: D a Int When solving the Wanted, we find that both Givens match, but we pick the second, because it has a weaker precondition, C a Int, compared to (Eq a, Num Int, C a Int). We thus say that d2 dominates d1; see Note [When does a quantified instance dominate another?]. This domination test is done purely in terms of superclass expansion, in the function GHC.Tc.Solver.Interact.impliedBySCs. We don't attempt to do a full round of constraint solving; this simple check suffices for now. Fixes #22216 and #22223
* implement proposal 106 (Define Kinds Without Promotion) (fixes #6024)Ross Paterson2022-09-274-6/+79
| | | | includes corresponding changes to haddock submodule
* Minor refactor around OutputableKrzysztof Gogolewski2022-09-221-2/+1
| | | | | | | * Replace 'text . show' and 'ppr' with 'int'. * Remove Outputable.hs-boot, no longer needed * Use pprWithCommas * Factor out instructions in AArch64 codegen
* Scrub partiality about `NewOrData`.M Farkas-Dyck2022-09-192-72/+64
| | | | | | | | Rather than a list of constructors and a `NewOrData` flag, we define `data DataDefnCons a = NewTypeCon a | DataTypeCons [a]`, which enforces a newtype to have exactly one constructor. Closes #22070. Bump haddock submodule.
* DeriveFunctor: Check for last type variables using dataConUnivTyVarsRyan Scott2022-09-183-22/+82
| | | | | | | | | | | | | | | | Previously, derived instances of `Functor` (as well as the related classes `Foldable`, `Traversable`, and `Generic1`) would determine which constraints to infer by checking for fields that contain the last type variable. The problem was that this last type variable was taken from `tyConTyVars`. For GADTs, the type variables in each data constructor are _not_ the same type variables as in `tyConTyVars`, leading to #22167. This fixes the issue by instead checking for the last type variable using `dataConUnivTyVars`. (This is very similar in spirit to the fix for #21185, which also replaced an errant use of `tyConTyVars` with type variables from each data constructor.) Fixes #22167.
* Clean up some. In particular:M Farkas-Dyck2022-09-177-20/+21
| | | | | | | | | | • Delete some dead code, largely under `GHC.Utils`. • Clean up a few definitions in `GHC.Utils.(Misc, Monad)`. • Clean up `GHC.Types.SrcLoc`. • Derive stock `Functor, Foldable, Traversable` for more types. • Derive more instances for newtypes. Bump haddock submodule.
View Lorry Controller Status