- Dec 24, 2023
-
-
Addresses #19278 This commit deprecates the underspecified -ddump-json flag and introduces a newer, well-specified flag -fdiagnostics-as-json. Also included is a JSON schema as part of the documentation. The -ddump-json flag will be slated for removal shortly after this merge.
-
- Dec 13, 2023
-
-
Summary of changes * Remove Language.Haskell.Syntax.Concrete * Move all tokens into GhcPs extension fields (LHsToken -> EpToken) * Create new TTG extension fields as needed * Drop the MultAnn wrapper Updates the haddock submodule. Co-authored-by:Alan Zimmerman <alan.zimm@gmail.com>
-
- Nov 27, 2023
-
-
* Generalise the metric logic by adding an additional field which allows you to specify how to query for the actual value. Previously the method of querying the baseline value was abstracted (but always set to the same thing). * This requires rejigging how the stat collection works slightly but now it's more uniform and hopefully simpler. * Introduce some new "generic" helper functions for writing generic stats tests. - collect_size ( deviation, path ) Record the size of the file as a metric - stat_from_file ( metric, deviation, path ) Read a value from the given path, and store that as a metric - collect_generic_stat ( metric, deviation, get_stat) Provide your own `get_stat` function, `lambda way: <Int>`, which can be used to establish the current value of the metric. - collect_generic_stats ( metric_info ): Like collect_generic_stat but provide the whole dictionary of metric definitions. { metric: { deviation: <Int> current: lambda way: <Int> } } * Introduce two new "size" metrics for keeping track of build products. - `size_hello_obj` - The size of `hello.o` from compiling hello.hs - `libdir` - The total size of the `libdir` folder. * Track the number of modules in the AST tests - CountDepsAst - CountDepsParser This lays the infrastructure for #24191 #22256 #17129
-
- Jul 05, 2023
-
-
In #22010 we established that Int was not always sufficient to store all the uniques we generate during compilation on 32-bit platforms. This commit addresses that problem by using Word64 instead of Int for uniques. The core of the change is in GHC.Core.Types.Unique and GHC.Core.Types.Unique.Supply. However, the representation of uniques is used in many other places, so those needed changes too. Additionally, the RTS has been extended with an atomic_inc64 operation. One major change from this commit is the introduction of the Word64Set and Word64Map data types. These are adapted versions of IntSet and IntMap from the containers package. These are planned to be upstreamed in the future. As a natural consequence of these changes, the compiler will be a bit slower and take more space on 32-bit platforms. Our CI tests indicate around a 5% residency increase. Metric Increase: CoOpt_Read CoOpt_Singletons LargeRecord ManyAlternatives ManyConstructors MultiComponentModules MultiComponentModulesRecomp MultiLayerModulesTH_OneShot RecordUpdPerf T10421 T10547 T12150 T12227 T12234 T12425 T12707 T13035 T13056 T13253 T13253-spj T13379 T13386 T13719 T14683 T14697 T14766 T15164 T15703 T16577 T16875 T17516 T18140 T18223 T18282 T18304 T18698a T18698b T18923 T1969 T19695 T20049 T21839c T3064 T3294 T4801 T5030 T5321FD T5321Fun T5631 T5642 T5837 T6048 T783 T8095 T9020 T9198 T9233 T9630 T9675 T9872a T9872b T9872b_defer T9872c T9872d T9961 TcPlugin_RewritePerf UniqLoop WWRec hard_hole_fits
-
- Jun 05, 2023
-
-
Matthew Pickering authored
These are in a separate commit as the improvement to these tests is the cumulative effect of the previous set of patches rather than just the responsibility of the last one in the patchset.
-
Matthew Pickering authored
The overall goal of this refactoring is to reduce the dependency footprint of the parser and syntax tree. Good reasons include: - Better module graph parallelisability - Make it easier to migrate error messages without introducing module loops - Philosophically, there's not reason for the AST to depend on half the compiler. One of the key edges which added this dependency was > GHC.Hs.Expr -> GHC.Tc.Types (TcLclEnv) As this in turn depending on TcM which depends on HscEnv and so on. Therefore the goal of this patch is to move `TcLclEnv` out of `GHC.Tc.Types` so that `GHC.Hs.Expr` can import TcLclEnv without incurring a huge dependency chain. The changes in this patch are: * Move TcLclEnv from GHC.Tc.Types to GHC.Tc.Types.LclEnv * Create new smaller modules for the types used in TcLclEnv New Modules: - GHC.Tc.Types.ErrCtxt - GHC.Tc.Types.BasicTypes - GHC.Tc.Types.TH - GHC.Tc.Types.LclEnv - GHC.Tc.Types.CtLocEnv - GHC.Tc.Errors.Types.PromotionErr Removed Boot File: - {-# SOURCE #-} GHC.Tc.Types * Introduce TcLclCtxt, the part of the TcLclEnv which doesn't participate in restoreLclEnv. * Replace TcLclEnv in CtLoc with specific CtLocEnv which is defined in GHC.Tc.Types.CtLocEnv. Use CtLocEnv in Implic and CtLoc to record the location of the implication and constraint. By splitting up TcLclEnv from GHC.Tc.Types we allow GHC.Hs.Expr to no longer depend on the TcM monad and all that entails. Fixes #23389 #23409
-
- May 31, 2023
-
-
This commit splits up the zonker into a few separate components, described in Note [The structure of the zonker] in `GHC.Tc.Zonk.Type`. 1. `GHC.Tc.Zonk.Monad` introduces a pared-down `TcM` monad, `ZonkM`, which has enough information for zonking types. This allows us to refactor `ErrCtxt` to use `ZonkM` instead of `TcM`, which guarantees we don't throw an error while reporting an error. 2. `GHC.Tc.Zonk.Env` is the new home of `ZonkEnv`, and also defines two zonking monad transformers, `ZonkT` and `ZonkBndrT`. `ZonkT` is a reader monad transformer over `ZonkEnv`. `ZonkBndrT m` is the codensity monad over `ZonkT m`. `ZonkBndrT` is used for computations that accumulate binders in the `ZonkEnv`. 3. `GHC.Tc.Zonk.TcType` contains the code for zonking types, for use in the typechecker. It uses the `ZonkM` monad. 4. `GHC.Tc.Zonk.Type` contains the code for final zonking to `Type`, which has been refactored to use `ZonkTcM = ZonkT TcM` and `ZonkBndrTcM = ZonkBndrT TcM`. Allocations slightly decrease on the whole due to using continuation-passing style instead of manual state passing of ZonkEnv in the final zonking to Type. ------------------------- Metric Decrease: T4029 T8095 T14766 T15304 hard_hole_fits RecordUpdPerf Metric Increase: T10421 ------------------------- -
-
-
-
- May 27, 2023
-
-
Also move targetPlatform selector Plenty of GHC needs just DynFlags. Even more can be made to use .DynFlags if more selectors is migrated. This is a low hanging fruit.
-
- May 15, 2023
-
-
This commit migrates the errors in GHC.Tc.Module to use the new diagnostic infrastructure. It required a significant overhaul of the compatibility checks between an hs-boot or signature module and its implementation; we now use a Writer monad to accumulate errors; see the BootMismatch datatype in GHC.Tc.Errors.Types, with its panoply of subtypes. For the sake of readability, several local functions inside the 'checkBootTyCon' function were split off into top-level functions. We split off GHC.Types.HscSource into a "boot or sig" vs "normal hs file" datatype, as this mirrors the logic in several other places where we want to treat hs-boot and hsig files in a similar fashion. This commit also refactors the Backpack checks for type synonyms implementing abstract data, to correctly reject implementations that contain qualified or quantified types (this fixes #23342 and #23344).
-
-
This will allow to make command line parsing to depend on diagnostic system (which depends on dynflags)
-
- Apr 18, 2023
-
-
This patch converts all the errors to do with loading interface files into proper structured diagnostics. * DriverMessage: Sometimes in the driver we attempt to load an interface file so we embed the IfaceMessage into the DriverMessage. * TcRnMessage: Most the time we are loading interface files during typechecking, so we embed the IfaceMessage This patch also removes the TcRnInterfaceLookupError constructor which is superceded by the IfaceMessage, which is now structured compared to just storing an SDoc before.
-
- Mar 29, 2023
-
-
sheaf authored
This patch moves the field-based logic for disambiguating record updates to the renamer. The type-directed logic, scheduled for removal, remains in the typechecker. To do this properly (and fix the myriad of bugs surrounding the treatment of duplicate record fields), we took the following main steps: 1. Create GREInfo, a renamer-level equivalent to TyThing which stores information pertinent to the renamer. This allows us to uniformly treat imported and local Names in the renamer, as described in Note [GREInfo]. 2. Remove GreName. Instead of a GlobalRdrElt storing GreNames, which distinguished between normal names and field names, we now store simple Names in GlobalRdrElt, along with the new GREInfo information which allows us to recover the FieldLabel for record fields. 3. Add namespacing for record fields, within the OccNames themselves. This allows us to remove the mangling of duplicate field selectors. This change ensures we don't print mangled names to the user in error messages, and allows us to handle duplicate record fields in Template Haskell. 4. Move record disambiguation to the renamer, and operate on the level of data constructors instead, to handle #21443. The error message text for ambiguous record updates has also been changed to reflect that type-directed disambiguation is on the way out. (3) means that OccEnv is now a bit more complex: we first key on the textual name, which gives an inner map keyed on NameSpace: OccEnv a ~ FastStringEnv (UniqFM NameSpace a) Note that this change, along with (2), both increase the memory residency of GlobalRdrEnv = OccEnv [GlobalRdrElt], which causes a few tests to regress somewhat in compile-time allocation. Even though (3) simplified a lot of code (in particular the treatment of field selectors within Template Haskell and in error messages), it came with one important wrinkle: in the situation of -- M.hs-boot module M where { data A; foo :: A -> Int } -- M.hs module M where { data A = MkA { foo :: Int } } we have that M.hs-boot exports a variable foo, which is supposed to match with the record field foo that M exports. To solve this issue, we add a new impedance-matching binding to M foo{var} = foo{fld} This mimics the logic that existed already for impedance-binding DFunIds, but getting it right was a bit tricky. See Note [Record field impedance matching] in GHC.Tc.Module. We also needed to be careful to avoid introducing space leaks in GHCi. So we dehydrate the GlobalRdrEnv before storing it anywhere, e.g. in ModIface. This means stubbing out all the GREInfo fields, with the function forceGlobalRdrEnv. When we read it back in, we rehydrate with rehydrateGlobalRdrEnv. This robustly avoids any space leaks caused by retaining old type environments. Fixes #13352 #14848 #17381 #17551 #19664 #21443 #21444 #21720 #21898 #21946 #21959 #22125 #22160 #23010 #23062 #23063 Updates haddock submodule ------------------------- Metric Increase: MultiComponentModules MultiLayerModules MultiLayerModulesDefsGhci MultiLayerModulesNoCode T13701 T14697 hard_hole_fits -------------------------
-
- Feb 21, 2023
-
-
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
-
- Jan 28, 2023
-
-
This patch removes some orphan instances in the STG namespace by introducing the GHC.Stg.Lift.Types module, which allows various type family instances to be moved to GHC.Stg.Syntax, avoiding orphan instances.
-
- Jan 17, 2023
-
-
This seems like a good idea either way, but is mostly motivated by a patch where this avoids a module loop.
-
- Dec 09, 2022
-
-
- Nov 11, 2022
-
-
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
-
This patch adds the wasm32-wasi tuple support to various places in the tree: autoconf, hadrian, ghc-boot and also the compiler. The codegen logic will come in subsequent commits.
-
- Nov 08, 2022
-
-
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].
-
- Nov 04, 2022
-
-
Introduces GHC.Prelude.Basic which can be used in modules which are a dependency of the ppr code.
-
- Oct 22, 2022
-
-
Vladislav Zavialov authored
Updates the haddock submodule.
-
- Oct 11, 2022
-
-
This commit adds three new flags * -fwrite-if-simplified-core: Writes the whole core program into an interface file * -fbyte-code-and-object-code: Generate both byte code and object code when compiling a file * -fprefer-byte-code: Prefer to use byte-code if it's available when running TH splices. The goal for including the core bindings in an interface file is to be able to restart the compiler pipeline at the point just after simplification and before code generation. Once compilation is restarted then code can be created for the byte code backend. This can significantly speed up start-times for projects in GHCi. HLS already implements its own version of these extended interface files for this reason. Preferring to use byte-code means that we can avoid some potentially expensive code generation steps (see #21700) * Producing object code is much slower than producing bytecode, and normally you need to compile with `-dynamic-too` to produce code in the static and dynamic way, the dynamic way just for Template Haskell execution when using a dynamically linked compiler. * Linking many large object files, which happens once per splice, can be quite expensive compared to linking bytecode. And you can get GHC to compile the necessary byte code so `-fprefer-byte-code` has access to it by using `-fbyte-code-and-object-code`. Fixes #21067
-
- Sep 28, 2022
-
-
Below are the noteworthy changes and if given their impact on compiler allocations for a type heavy module: * Use the oneShot trick on LintM * Use a unboxed tuple for the result of LintM: ~6% reduction * Avoid a thunk for the result of typeKind in lintType: ~5% reduction * lint_app: Don't allocate the error msg in the hot code path: ~4% reduction * lint_app: Eagerly force the in scope set: ~4% * nonDetCmpType: Try to short cut using reallyUnsafePtrEquality#: ~2% * lintM: Use a unboxed maybe for the `a` result: ~12% * lint_app: make go_app tail recursive to avoid allocating the go function as heap closure: ~7% * expandSynTyCon_maybe: Use a specialized data type For a less type heavy module like nofib/spectral/simple compiled with -O -dcore-lint allocations went down by ~24% and compile time by ~9%. ------------------------- Metric Decrease: T1969 -------------------------
-
- Sep 13, 2022
-
-
- Aug 10, 2022
-
-
This patch adds a new command-line flag: -fplugin-library=<file-path>;<unit-id>;<module>;<args> used like this: -fplugin-library=path/to/plugin.so;package-123;Plugin.Module;["Argument","List"] It allows a plugin to be loaded directly from a shared library. With this approach, GHC doesn't compile anything for the plugin and doesn't load any .hi file for the plugin and its dependencies. As such GHC doesn't need to support two environments (one for plugins, one for target code), which was the more ambitious approach tracked in #14335. Fix #20964 Co-authored-by:Josh Meredith <joshmeredith2008@gmail.com>
-
- Jul 22, 2022
-
-
* Removed references to driver from GHC.Core.LateCC, GHC.Core.Simplify namespace and GHC.Core.Opt.Stats. Also removed services from configuration records. * Renamed GHC.Core.Opt.Simplify to GHC.Core.Opt.Simplify.Iteration. * Inlined `simplifyPgm` and renamed `simplifyPgmIO` to `simplifyPgm` and moved the Simplify driver to GHC.Core.Opt.Simplify. * Moved `SimplMode` and `FloatEnable` to GHC.Core.Opt.Simplify.Env. * Added a configuration record `TopEnvConfig` for the `SimplTopEnv` environment in GHC.Core.Opt.Simplify.Monad. * Added `SimplifyOpts` and `SimplifyExprOpts`. Provide initialization functions for those in a new module GHC.Driver.Config.Core.Opt.Simplify. Also added initialization functions for `SimplMode` to that module. * Moved `CoreToDo` and friends to a new module GHC.Core.Pipeline.Types and the counting types and functions (`SimplCount` and `Tick`) to new module GHC.Core.Opt.Stats. * Added getter functions for the fields of `SimplMode`. The pedantic bottoms option and the platform are retrieved from the ArityOpts and RuleOpts and the getter functions allow us to retrieve values from `SpecEnv` without the knowledge where the data is stored exactly. * Moved the coercion optimization options from the top environment to `SimplMode`. This way the values left in the top environment are those dealing with monadic functionality, namely logging, IO related stuff and counting. Added a note "The environments of the Simplify pass". * Removed `CoreToDo` from GHC.Core.Lint and GHC.CoreToStg.Prep and got rid of `CoreDoSimplify`. Pass `SimplifyOpts` in the `CoreToDo` type instead. * Prep work before removing `InteractiveContext` from `HscEnv`.
-
- Jul 16, 2022
-
-
Here we reorganize `GHC.Cmm` to eliminate the orphan `Outputable` and `OutputableP` instances for the Cmm AST. This makes it significantly easier to use the Cmm pretty-printers in tracing output without incurring module import cycles.
-
- Jul 06, 2022
-
-
Continue to prune the `Language.Haskell.Syntax.*` modules out of GHC imports according to the plan in the linked issue. Moves more GHC-specific declarations to `GHC.*` and brings more required GHC-independent declarations to `Language.Haskell.Syntax.*` (extending e.g. `Language.Haskell.Syntax.Basic`). Progress towards #21592 Bump haddock submodule for !8308 ------------------------- Metric Decrease: hard_hole_fits -------------------------
-
- Jul 03, 2022
-
-
ModuleName used to live in GHC.Unit.Module.Name. In this commit, the definition of ModuleName and its associated functions are moved to Language.Haskell.Syntax.Module.Name according to the current plan towards making the AST GHC-independent. The instances for ModuleName for Outputable, Uniquable and Binary were moved to the module in which the class is defined because these instances depend on GHC. The instance of Eq for ModuleName is slightly changed to no longer depend on unique explicitly and instead uses FastString's instance of Eq.
-
Move the GHC-independent definitions from GHC.Hs.ImpExp to Language.Haskell.Syntax.ImpExp with the required TTG extension fields such as to keep the AST independent from GHC. This is progress towards having the haskell-syntax package, as described in #21592 Bumps haddock submodule
-
- Jun 20, 2022
-
-
Sebastian Graf authoredIn #20836 we have optimised a terminating program into an endless loop, because we speculated the self-recursive call of a recursive DFun. Now we track the set of enclosing recursive binders in CorePrep to prevent speculation of such self-recursive calls. See the updates to Note [Speculative evaluation] for details. Fixes #20836.
-
- Jun 07, 2022
-
-
John Ericson authored
Co-Authored-By:Andre Marianiello <andremarianiello@users.noreply.github.com>
-
John Ericson authored
It is redundant information and a source of needless version control conflicts when multiple MRs are changing the deps list. Just printing the list and not also its length is fine.
-
- Jun 02, 2022
-
-
John Ericson authored
Finishes what !7467 (closed) started. Progress towards #17957
-
- May 31, 2022
-
-
John Ericson authored
Progress towards #17957 Because of `CoreM`, I did not move the `DynFlags` and `HscEnv` to other modules as thoroughly as I usually do. This does mean that risk of `DynFlags` "creeping back in" is higher than it usually is. After we do the same process to the other Core passes, and then figure out what we want to do about `CoreM`, we can finish the job started here. That is a good deal more work, however, so it certainly makes sense to land this now.
-
- May 21, 2022
-
-
With this change, `Backend` becomes an abstract type (there are no more exposed value constructors). Decisions that were formerly made by asking "is the current back end equal to (or different from) this named value constructor?" are now made by interrogating the back end about its properties, which are functions exported by `GHC.Driver.Backend`. There is a description of how to migrate code using `Backend` in the user guide. Clients using the GHC API can find a backdoor to access the Backend datatype in GHC.Driver.Backend.Internal. Bumps haddock submodule. Fixes #20927
-
