summaryrefslogtreecommitdiff
path: root/compiler/GHC/Tc/Module.hs
Commit message (Collapse)AuthorAgeFilesLines
* compiler: Introduce and use RoughMap for instance environmentsBen Gamari2022-02-041-11/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Here we introduce a new data structure, RoughMap, inspired by the previous `RoughTc` matching mechanism for checking instance matches. This allows [Fam]InstEnv to be implemented as a trie indexed by these RoughTc signatures, reducing the complexity of instance lookup and FamInstEnv merging (done during the family instance conflict test) from O(n) to O(log n). The critical performance improvement currently realised by this patch is in instance matching. In particular the RoughMap mechanism allows us to discount many potential instances which will never match for constraints involving type variables (see Note [Matching a RoughMap]). In realistic code bases matchInstEnv was accounting for 50% of typechecker time due to redundant work checking instances when simplifying instance contexts when deriving instances. With this patch the cost is significantly reduced. The larger constants in InstEnv creation do mean that a few small tests regress in allocations slightly. However, the runtime of T19703 is reduced by a factor of 4. Moreover, the compilation time of the Cabal library is slightly improved. A couple of test cases are included which demonstrate significant improvements in compile time with this patch. This unfortunately does not fix the testcase provided in #19703 but does fix #20933 ------------------------- Metric Decrease: T12425 Metric Increase: T13719 T9872a T9872d hard_hole_fits ------------------------- Co-authored-by: Matthew Pickering <matthewtpickering@gmail.com>
* Rework the handling of SkolemInfoMatthew Pickering2022-01-291-10/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The main purpose of this patch is to attach a SkolemInfo directly to each SkolemTv. This fixes the large number of bugs which have accumulated over the years where we failed to report errors due to having "no skolem info" for particular type variables. Now the origin of each type varible is stored on the type variable we can always report accurately where it cames from. Fixes #20969 #20732 #20680 #19482 #20232 #19752 #10946 #19760 #20063 #13499 #14040 The main changes of this patch are: * SkolemTv now contains a SkolemInfo field which tells us how the SkolemTv was created. Used when reporting errors. * Enforce invariants relating the SkolemInfoAnon and level of an implication (ic_info, ic_tclvl) to the SkolemInfo and level of the type variables in ic_skols. * All ic_skols are TcTyVars -- Check is currently disabled * All ic_skols are SkolemTv * The tv_lvl of the ic_skols agrees with the ic_tclvl * The ic_info agrees with the SkolInfo of the implication. These invariants are checked by a debug compiler by checkImplicationInvariants. * Completely refactor kcCheckDeclHeader_sig which kept doing my head in. Plus, it wasn't right because it wasn't skolemising the binders as it decomposed the kind signature. The new story is described in Note [kcCheckDeclHeader_sig]. The code is considerably shorter than before (roughly 240 lines turns into 150 lines). It still has the same awkward complexity around computing arity as before, but that is a language design issue. See Note [Arity inference in kcCheckDeclHeader_sig] * I added new type synonyms MonoTcTyCon and PolyTcTyCon, and used them to be clear which TcTyCons have "finished" kinds etc, and which are monomorphic. See Note [TcTyCon, MonoTcTyCon, and PolyTcTyCon] * I renamed etaExpandAlgTyCon to splitTyConKind, becuase that's a better name, and it is very useful in kcCheckDeclHeader_sig, where eta-expansion isn't an issue. * Kill off the nasty `ClassScopedTvEnv` entirely. Co-authored-by: Simon Peyton Jones <simon.peytonjones@gmail.com>
* Define and use restoreLclEnvSimon Peyton Jones2022-01-271-40/+41
| | | | | | | | | This fixes #20981. See Note [restoreLclEnv vs setLclEnv] in GHC.Tc.Utils.Monad. I also use updLclEnv rather than get/set when I can, because it's then much clearer that it's an update rather than an entirely new TcLclEnv coming from who-knows-where.
* Multiple Home UnitsMatthew Pickering2021-12-281-9/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Multiple home units allows you to load different packages which may depend on each other into one GHC session. This will allow both GHCi and HLS to support multi component projects more naturally. Public Interface ~~~~~~~~~~~~~~~~ In order to specify multiple units, the -unit @⟨filename⟩ flag is given multiple times with a response file containing the arguments for each unit. The response file contains a newline separated list of arguments. ``` ghc -unit @unitLibCore -unit @unitLib ``` where the `unitLibCore` response file contains the normal arguments that cabal would pass to `--make` mode. ``` -this-unit-id lib-core-0.1.0.0 -i -isrc LibCore.Utils LibCore.Types ``` The response file for lib, can specify a dependency on lib-core, so then modules in lib can use modules from lib-core. ``` -this-unit-id lib-0.1.0.0 -package-id lib-core-0.1.0.0 -i -isrc Lib.Parse Lib.Render ``` Then when the compiler starts in --make mode it will compile both units lib and lib-core. There is also very basic support for multiple home units in GHCi, at the moment you can start a GHCi session with multiple units but only the :reload is supported. Most commands in GHCi assume a single home unit, and so it is additional work to work out how to modify the interface to support multiple loaded home units. Options used when working with Multiple Home Units There are a few extra flags which have been introduced specifically for working with multiple home units. The flags allow a home unit to pretend it’s more like an installed package, for example, specifying the package name, module visibility and reexported modules. -working-dir ⟨dir⟩ It is common to assume that a package is compiled in the directory where its cabal file resides. Thus, all paths used in the compiler are assumed to be relative to this directory. When there are multiple home units the compiler is often not operating in the standard directory and instead where the cabal.project file is located. In this case the -working-dir option can be passed which specifies the path from the current directory to the directory the unit assumes to be it’s root, normally the directory which contains the cabal file. When the flag is passed, any relative paths used by the compiler are offset by the working directory. Notably this includes -i and -I⟨dir⟩ flags. -this-package-name ⟨name⟩ This flag papers over the awkward interaction of the PackageImports and multiple home units. When using PackageImports you can specify the name of the package in an import to disambiguate between modules which appear in multiple packages with the same name. This flag allows a home unit to be given a package name so that you can also disambiguate between multiple home units which provide modules with the same name. -hidden-module ⟨module name⟩ This flag can be supplied multiple times in order to specify which modules in a home unit should not be visible outside of the unit it belongs to. The main use of this flag is to be able to recreate the difference between an exposed and hidden module for installed packages. -reexported-module ⟨module name⟩ This flag can be supplied multiple times in order to specify which modules are not defined in a unit but should be reexported. The effect is that other units will see this module as if it was defined in this unit. The use of this flag is to be able to replicate the reexported modules feature of packages with multiple home units. Offsetting Paths in Template Haskell splices ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ When using Template Haskell to embed files into your program, traditionally the paths have been interpreted relative to the directory where the .cabal file resides. This causes problems for multiple home units as we are compiling many different libraries at once which have .cabal files in different directories. For this purpose we have introduced a way to query the value of the -working-dir flag to the Template Haskell API. By using this function we can implement a makeRelativeToProject function which offsets a path which is relative to the original project root by the value of -working-dir. ``` import Language.Haskell.TH.Syntax ( makeRelativeToProject ) foo = $(makeRelativeToProject "./relative/path" >>= embedFile) ``` > If you write a relative path in a Template Haskell splice you should use the makeRelativeToProject function so that your library works correctly with multiple home units. A similar function already exists in the file-embed library. The function in template-haskell implements this function in a more robust manner by honouring the -working-dir flag rather than searching the file system. Closure Property for Home Units ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ For tools or libraries using the API there is one very important closure property which must be adhered to: > Any dependency which is not a home unit must not (transitively) depend on a home unit. For example, if you have three packages p, q and r, then if p depends on q which depends on r then it is illegal to load both p and r as home units but not q, because q is a dependency of the home unit p which depends on another home unit r. If you are using GHC by the command line then this property is checked, but if you are using the API then you need to check this property yourself. If you get it wrong you will probably get some very confusing errors about overlapping instances. Limitations of Multiple Home Units ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ There are a few limitations of the initial implementation which will be smoothed out on user demand. * Package thinning/renaming syntax is not supported * More complicated reexports/renaming are not yet supported. * It’s more common to run into existing linker bugs when loading a large number of packages in a session (for example #20674, #20689) * Backpack is not yet supported when using multiple home units. * Dependency chasing can be quite slow with a large number of modules and packages. * Loading wired-in packages as home units is currently not supported (this only really affects GHC developers attempting to load template-haskell). * Barely any normal GHCi features are supported, it would be good to support enough for ghcid to work correctly. Despite these limitations, the implementation works already for nearly all packages. It has been testing on large dependency closures, including the whole of head.hackage which is a total of 4784 modules from 452 packages. Internal Changes ~~~~~~~~~~~~~~~~ * The biggest change is that the HomePackageTable is replaced with the HomeUnitGraph. The HomeUnitGraph is a map from UnitId to HomeUnitEnv, which contains information specific to each home unit. * The HomeUnitEnv contains: - A unit state, each home unit can have different package db flags - A set of dynflags, each home unit can have different flags - A HomePackageTable * LinkNode: A new node type is added to the ModuleGraph, this is used to place the linking step into the build plan so linking can proceed in parralel with other packages being built. * New invariant: Dependencies of a ModuleGraphNode can be completely determined by looking at the value of the node. In order to achieve this, downsweep now performs a more complete job of downsweeping and then the dependenices are recorded forever in the node rather than being computed again from the ModSummary. * Some transitive module calculations are rewritten to use the ModuleGraph which is more efficient. * There is always an active home unit, which simplifies modifying a lot of the existing API code which is unit agnostic (for example, in the driver). The road may be bumpy for a little while after this change but the basics are well-tested. One small metric increase, which we accept and also submodule update to haddock which removes ExtendedModSummary. Closes #10827 ------------------------- Metric Increase: MultiLayerModules ------------------------- Co-authored-by: Fendor <power.walross@gmail.com>
* Give plugins a better interface (#17957)Sylvain Henry2021-12-211-5/+5
| | | | | | | | | | | | Plugins were directly fetched from HscEnv (hsc_static_plugins and hsc_plugins). The tight coupling of plugins and of HscEnv is undesirable and it's better to store them in a new Plugins datatype and to use it in the plugins' API (e.g. withPlugins, mapPlugins...). In the process, the interactive context (used by GHCi) got proper support for different static plugins than those used for loaded modules. Bump haddock submodule
* Ghci environment: Do not remove shadowed idsJoachim Breitner2021-12-141-19/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Names defined earier but shadowed need to be kept around, e.g. for type signatures: ``` ghci> data T = T ghci> let t = T ghci> data T = T ghci> :t t t :: Ghci1.T ``` and indeed they can be used: ``` ghci> let t2 = Ghci1.T :: Ghci1.T ghci> :t t2 t2 :: Ghci1.T ``` However, previously this did not happen for ids (non-types), although they are still around under the qualified name internally: ``` ghci> let t = "other t" ghci> t' <interactive>:8:1: error: • Variable not in scope: t' • Perhaps you meant one of these: ‘Ghci2.t’ (imported from Ghci2), ‘t’ (line 7), ‘t2’ (line 5) ghci> Ghci2.t <interactive>:9:1: error: • GHC internal error: ‘Ghci2.t’ is not in scope during type checking, but it passed the renamer tcl_env of environment: [] • In the expression: Ghci2.t In an equation for ‘it’: it = Ghci2.t ``` This fixes the problem by simply removing the code that tries to remove shadowed ids from the environment. Now you can refer to shadowed ids using `Ghci2.t`, just like you can do for data and type constructors. This simplifies the code, makes terms and types more similar, and also fixes #20455. Now all names ever defined in GHCi are in `ic_tythings`, which is printed by `:show bindings`. But for that commands, it seems to be more ergonomic to only list those bindings that are not shadowed. Or, even if it is not more ergonomic, it’s the current behavour. So let's restore that by filtering in `icInScopeTTs`. Of course a single `TyThing` can be associated with many names. We keep it it in the bindings if _any_ of its names are still visible unqualifiedly. It's a judgement call. This commit also turns a rather old comment into a test files. The comment is is rather stale and things are better explained elsewhere. Fixes #925. Two test cases are regressing: T14052(ghci) ghc/alloc 2749444288.0 12192109912.0 +343.4% BAD T14052Type(ghci) ghc/alloc 7365784616.0 10767078344.0 +46.2% BAD This is not unexpected; the `ic_tythings list grows` a lot more if we don’t remove shadowed Ids. I tried to alleviate it a bit with earlier MRs, but couldn’t make up for it completely. Metric Increase: T14052 T14052Type
* package imports: Take into account package visibility when renamingMatthew Pickering2021-12-091-2/+2
| | | | | | | | | | | | In 806e49ae the package imports refactoring code was modified to rename package imports. There was a small oversight which meant the code didn't account for module visibility. This patch fixes that oversight. In general the "lookupPackageName" function is unsafe to use as it doesn't account for package visiblity/thinning/renaming etc, there is just one use in the compiler which would be good to audit. Fixes #20779
* Misc cleanupKrzysztof Gogolewski2021-11-251-1/+1
| | | | | | | | | | | | | | | | | | | | | * Remove `getTag_RDR` (unused), `tidyKind` and `tidyOpenKind` (already available as `tidyType` and `tidyOpenType`) * Remove Note [Explicit Case Statement for Specificity]. Since 0a709dd9876e40 we require GHC 8.10 for bootstrapping. * Change the warning to `cmpAltCon` to a panic. This shouldn't happen. If it ever does, the code was wrong anyway: it shouldn't always return `LT`, but rather `LT` in one case and `GT` in the other case. * Rename `verifyLinearConstructors` to `verifyLinearFields` * Fix `Note [Local record selectors]` which was not referenced * Remove vestiges of `type +v` * Minor fixes to StaticPointers documentation, part of #15603
* Export `withTcPlugins` and `withHoleFitPlugins`Ziyang Liu2021-11-061-0/+2
|
* EPA: Use LocatedA for ModuleNameAlan Zimmerman2021-10-241-2/+2
| | | | | This allows us to use an Anchor with a DeltaPos in it when exact printing.
* Refactor package importsSylvain Henry2021-10-221-9/+8
| | | | | | | | | Use an (Raw)PkgQual datatype instead of `Maybe FastString` to represent package imports. Factorize the code that renames RawPkgQual into PkgQual in function `rnPkgQual`. Renaming consists in checking if the FastString is the magic "this" keyword, the home-unit unit-id or something else. Bump haddock submodule
* InteractiveContext: Smarter caching when rebuilding the ic_rn_gbl_envJoachim Breitner2021-10-191-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | The GlobalRdrEnv of a GHCI session changes in odd ways: New bindings are not just added "to the end", but also "in the middle", namely when changing the set of imports: These are treated as if they happened before all bindings from the prompt, even those that happened earlier. Previously, this meant that the `ic_rn_gbl_env` is recalculated from the `ic_tythings`. But this wasteful if `ic_tythings` has many entries that define the same unqualified name. By separately keeping track of a `GlobalRdrEnv` of all the locally defined things we can speed this operation up significantly. This change improves `T14052Type` by 60% (It used to be 70%, but it looks that !6723 already reaped some of the rewards). But more importantly, it hopefully unblocks #20455, becaues with this smarter caching, the change needed to fix that issue will no longer make `T14052` explode. I hope. It does regress `T14052` by 30%; caching isn’t free. Oh well. Metric Decrease: T14052Type Metric Increase: T14052
* Introduce Concrete# for representation polymorphism checkssheaf2021-10-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | PHASE 1: we never rewrite Concrete# evidence. This patch migrates all the representation polymorphism checks to the typechecker, using a new constraint form Concrete# :: forall k. k -> TupleRep '[] Whenever a type `ty` must be representation-polymorphic (e.g. it is the type of an argument to a function), we emit a new `Concrete# ty` Wanted constraint. If this constraint goes unsolved, we report a representation-polymorphism error to the user. The 'FRROrigin' datatype keeps track of the context of the representation-polymorphism check, for more informative error messages. This paves the way for further improvements, such as allowing type families in RuntimeReps and improving the soundness of typed Template Haskell. This is left as future work (PHASE 2). fixes #17907 #20277 #20330 #20423 #20426 updates haddock submodule ------------------------- Metric Decrease: T5642 -------------------------
* Add defaulting plugins.Andrei Barbu2021-10-081-15/+28
| | | | | | | | | | | | | | | Like the built-in type defaulting rules these plugins can propose candidates to resolve ambiguous type variables. Machine learning and other large APIs like those for game engines introduce new numeric types and other complex typed APIs. The built-in defaulting mechanism isn't powerful enough to resolve ambiguous types in these cases forcing users to specify minutia that they might not even know how to do. There is an example defaulting plugin linked in the documentation. Applications include defaulting the device a computation executes on, if a gradient should be computed for a tensor, or the size of a tensor. See https://github.com/ghc-proposals/ghc-proposals/pull/396 for details.
* compiler: occEnvElts -> nonDetOccEnvEltsBen Gamari2021-09-291-2/+2
|
* compiler: Rewrite all eltsUFM occurrences to nonDetEltsUFMBen Gamari2021-09-291-1/+1
| | | | And remove the former.
* TH stage restriction check for constructors, selectors, and class methodsAndrea Condoluci2021-09-291-4/+6
| | | | Closes ticket #17820.
* Add rewriting to typechecking pluginssheaf2021-08-131-7/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | Type-checking plugins can now directly rewrite type-families. The TcPlugin record is given a new field, tcPluginRewrite. The plugin specifies how to rewrite certain type-families with a value of type `UniqFM TyCon TcPluginRewriter`, where: type TcPluginRewriter = RewriteEnv -- Rewriter environment -> [Ct] -- Givens -> [TcType] -- type family arguments -> TcPluginM TcPluginRewriteResult data TcPluginRewriteResult = TcPluginNoRewrite | TcPluginRewriteTo { tcPluginRewriteTo :: Reduction , tcRewriterNewWanteds :: [Ct] } When rewriting an exactly-saturated type-family application, GHC will first query type-checking plugins for possible rewritings before proceeding. Includes some changes to the TcPlugin API, e.g. removal of the EvBindsVar parameter to the TcPluginM monad.
* Refactoring module dependenciesSylvain Henry2021-08-131-1/+2
| | | | | | | | | | | | | | * Make mkDependencies pure * Use Sets instead of sorted lists Notable perf changes: MultiLayerModules(normal) ghc/alloc 4130851520.0 2981473072.0 -27.8% T13719(normal) ghc/alloc 4313296052.0 4151647512.0 -3.7% Metric Decrease: MultiLayerModules T13719
* Refactor HsStmtContext and remove HsDoRnArtyom Kuznetsov2021-08-101-2/+2
| | | | | | | | | Parts of HsStmtContext were split into a separate data structure HsDoFlavour. Before this change HsDo used to have HsStmtContext inside, but in reality only parts of HsStmtContext were used and other cases were invariants handled with panics. Separating those parts into its own data structure helps us to get rid of those panics as well as HsDoRn type family.
* Use Reductions to keep track of rewritingssheaf2021-08-041-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | We define Reduction = Reduction Coercion !Type. A reduction of the form 'Reduction co new_ty' witnesses an equality ty ~co~> new_ty. That is, the rewriting happens left-to-right: the right-hand-side type of the coercion is the rewritten type, and the left-hand-side type the original type. Sticking to this convention makes the codebase more consistent, helping to avoid certain applications of SymCo. This replaces the parts of the codebase which represented reductions as pairs, (Coercion,Type) or (Type,Coercion). Reduction being strict in the Type argument improves performance in some programs that rewrite many type families (such as T9872). Fixes #20161 ------------------------- Metric Decrease: T5321Fun T9872a T9872b T9872c T9872d -------------------------
* Dynflags: introduce DiagOptsSylvain Henry2021-07-011-1/+3
| | | | | | | | | | | | | | | | | | | | | | Use DiagOpts for diagnostic options instead of directly querying DynFlags (#17957). Surprising performance improvements on CI: T4801(normal) ghc/alloc 313236344.0 306515216.0 -2.1% GOOD T9961(normal) ghc/alloc 384502736.0 380584384.0 -1.0% GOOD ManyAlternatives(normal) ghc/alloc 797356128.0 786644928.0 -1.3% ManyConstructors(normal) ghc/alloc 4389732432.0 4317740880.0 -1.6% T783(normal) ghc/alloc 408142680.0 402812176.0 -1.3% Metric Decrease: T4801 T9961 T783 ManyAlternatives ManyConstructors Bump haddock submodule
* Try to simplify zoo of functions in `Tc.Utils.Monad`Alfredo Di Napoli2021-06-281-19/+32
| | | | | | | | | | | This commit tries to untangle the zoo of diagnostic-related functions in `Tc.Utils.Monad` so that we can have the interfaces mentions only `TcRnMessage`s while we push the creation of these messages upstream. It also ports TcRnMessage diagnostics to use the new API, in particular this commit switch to use TcRnMessage in the external interfaces of the diagnostic functions, and port the old SDoc to be wrapped into TcRnUnknownMessage.
* Converts diagnostics for two errors in Ghc.Tc.Module (#19926)Aaron Allen2021-06-231-7/+2
| | | | | | | | This adds constructors to TcRnMessage to replace use of TcRnUnknownMessage in Ghc.Tc.Module. Adds a test case for the UnsafeDueToPlugin warning. Closes #19926
* Reword: representation instead of levitysheaf2021-06-101-1/+2
| | | | fixes #19756, updates haddock submodule
* Make Logger independent of DynFlagsSylvain Henry2021-06-071-5/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce LogFlags as a independent subset of DynFlags used for logging. As a consequence in many places we don't have to pass both Logger and DynFlags anymore. The main reason for this refactoring is that I want to refactor the systools interfaces: for now many systools functions use DynFlags both to use the Logger and to fetch their parameters (e.g. ldInputs for the linker). I'm interested in refactoring the way they fetch their parameters (i.e. use dedicated XxxOpts data types instead of DynFlags) for #19877. But if I did this refactoring before refactoring the Logger, we would have duplicate parameters (e.g. ldInputs from DynFlags and linkerInputs from LinkerOpts). Hence this patch first. Some flags don't really belong to LogFlags because they are subsystem specific (e.g. most DumpFlags). For example -ddump-asm should better be passed in NCGConfig somehow. This patch doesn't fix this tight coupling: the dump flags are part of the UI but they are passed all the way down for example to infer the file name for the dumps. Because LogFlags are a subset of the DynFlags, we must update the former when the latter changes (not so often). As a consequence we now use accessors to read/write DynFlags in HscEnv instead of using `hsc_dflags` directly. In the process I've also made some subsystems less dependent on DynFlags: - CmmToAsm: by passing some missing flags via NCGConfig (see new fields in GHC.CmmToAsm.Config) - Core.Opt.*: - by passing -dinline-check value into UnfoldingOpts - by fixing some Core passes interfaces (e.g. CallArity, FloatIn) that took DynFlags argument for no good reason. - as a side-effect GHC.Core.Opt.Pipeline.doCorePass is much less convoluted.
* Specify the reason for import for the backpack's extra importsDivam2021-06-021-4/+8
|
* Extensible Hints for diagnostic messagesAlfredo Di Napoli2021-05-201-2/+2
| | | | | | | | | | | | | | | | | | This commit extends the GHC diagnostic hierarchy with a `GhcHint` type, modelling helpful suggestions emitted by GHC which can be used to deal with a particular warning or error. As a direct consequence of this, the `Diagnostic` typeclass has been extended with a `diagnosticHints` method, which returns a `[GhcHint]`. This means that now we can clearly separate out the printing of the diagnostic message with the suggested fixes. This is done by extending the `printMessages` function in `GHC.Driver.Errors`. On top of that, the old `PsHint` type has been superseded by the new `GhcHint` type, which de-duplicates some hints in favour of a general `SuggestExtension` constructor that takes a `GHC.LanguageExtensions.Extension`.
* Remove wired-in names hs-boot check bypass (#19855)Sylvain Henry2021-05-191-3/+0
| | | | The check bypass is no longer necessary and the check would have avoided #19638.
* Remove transitive information about modules and packages from interface filesMatthew Pickering2021-05-191-11/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit modifies interface files so that *only* direct information about modules and packages is stored in the interface file. * Only direct module and direct package dependencies are stored in the interface files. * Trusted packages are now stored separately as they need to be checked transitively. * hs-boot files below the compiled module in the home module are stored so that eps_is_boot can be calculated in one-shot mode without loading all interface files in the home package. * The transitive closure of signatures is stored separately This is important for two reasons * Less recompilation is needed, as motivated by #16885, a lot of redundant compilation was triggered when adding new imports deep in the module tree as all the parent interface files had to be redundantly updated. * Checking an interface file is cheaper because you don't have to perform a transitive traversal to check the dependencies are up-to-date. In the code, places where we would have used the transitive closure, we instead compute the necessary transitive closure. The closure is not computed very often, was already happening in checkDependencies, and was already happening in getLinkDeps. Fixes #16885 ------------------------- Metric Decrease: MultiLayerModules T13701 T13719 -------------------------
* Fully remove HsVersions.hSylvain Henry2021-05-121-2/+0
| | | | | | | | | | Replace uses of WARN macro with calls to: warnPprTrace :: Bool -> SDoc -> a -> a Remove the now unused HsVersions.h Bump haddock submodule
* Replace CPP assertions with Haskell functionsSylvain Henry2021-05-121-7/+8
| | | | | | | | | | | | | | | There is no reason to use CPP. __LINE__ and __FILE__ macros are now better replaced with GHC's CallStack. As a bonus, assert error messages now contain more information (function name, column). Here is the mapping table (HasCallStack omitted): * ASSERT: assert :: Bool -> a -> a * MASSERT: massert :: Bool -> m () * ASSERTM: assertM :: m Bool -> m () * ASSERT2: assertPpr :: Bool -> SDoc -> a -> a * MASSERT2: massertPpr :: Bool -> SDoc -> m () * ASSERTM2: assertPprM :: m Bool -> SDoc -> m ()
* Bring tcTyConScopedTyVars into scope in tcClassDecl2Ryan Scott2021-04-301-5/+10
| | | | | | | | | | | It is possible that the type variables bound by a class header will map to something different in the typechecker in the presence of `StandaloneKindSignatures`. `tcClassDecl2` was not aware of this, however, leading to #19738. To fix it, in `tcTyClDecls` we map each class `TcTyCon` to its `tcTyConScopedTyVars` as a `ClassScopedTVEnv`. We then plumb that `ClassScopedTVEnv` to `tcClassDecl2` where it can be used. Fixes #19738.
* Add GhcMessage and ancillary typesAlfredo Di Napoli2021-04-291-15/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit adds GhcMessage and ancillary (PsMessage, TcRnMessage, ..) types. These types will be expanded to represent more errors generated by different subsystems within GHC. Right now, they are underused, but more will come in the glorious future. See https://gitlab.haskell.org/ghc/ghc/-/wikis/Errors-as-(structured)-values for a design overview. Along the way, lots of other things had to happen: * Adds Semigroup and Monoid instance for Bag * Fixes #19746 by parsing OPTIONS_GHC pragmas into Located Strings. See GHC.Parser.Header.toArgs (moved from GHC.Utils.Misc, where it didn't belong anyway). * Addresses (but does not completely fix) #19709, now reporting desugarer warnings and errors appropriately for TH splices. Not done: reporting type-checker warnings for TH splices. * Some small refactoring around Safe Haskell inference, in order to keep separate classes of messages separate. * Some small refactoring around initDsTc, in order to keep separate classes of messages separate. * Separate out the generation of messages (that is, the construction of the text block) from the wrapping of messages (that is, assigning a SrcSpan). This is more modular than the previous design, which mixed the two. Close #19746. This was a collaborative effort by Alfredo di Napoli and Richard Eisenberg, with a key assist on #19746 by Iavor Diatchki. Metric Increase: MultiLayerModules
* More accurate SrcSpan when reporting redundant constraintsSimon Peyton Jones2021-04-121-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | We want an accurate SrcSpan for redundant constraints: • Redundant constraint: Eq a • In the type signature for: f :: forall a. Eq a => a -> () | 5 | f :: Eq a => a -> () | ^^^^ This patch adds some plumbing to achieve this * New data type GHC.Tc.Types.Origin.ReportRedundantConstraints (RRC) * This RRC value is kept inside - FunSigCtxt - ExprSigCtxt * Then, when reporting the error in GHC.Tc.Errors, use this SrcSpan to control the error message: GHC.Tc.Errors.warnRedundantConstraints Quite a lot of files are touched in a boring way.
* Introduce SevIgnore Severity to suppress warningsAlfredo Di Napoli2021-04-051-3/+2
| | | | | | | | | | | | | | | | | | | | | | This commit introduces a new `Severity` type constructor called `SevIgnore`, which can be used to classify diagnostic messages which are not meant to be displayed to the user, for example suppressed warnings. This extra constructor allows us to get rid of a bunch of redundant checks when emitting diagnostics, typically in the form of the pattern: ``` when (optM Opt_XXX) $ addDiagnosticTc (WarningWithFlag Opt_XXX) ... ``` Fair warning! Not all checks should be omitted/skipped, as evaluating some data structures used to produce a diagnostic might still be expensive (e.g. zonking, etc). Therefore, a case-by-case analysis must be conducted when deciding if a check can be removed or not. Last but not least, we remove the unnecessary `CmdLine.WarnReason` type, which is now redundant with `DiagnosticReason`.
* Compute Severity of diagnostics at birthAlfredo Di Napoli2021-04-011-2/+2
| | | | | | | | | | | | | | | | | | | | | This commit further expand on the design for #18516 by getting rid of the `defaultReasonSeverity` in favour of a function called `diagReasonSeverity` which correctly takes the `DynFlags` as input. The idea is to compute the `Severity` and the `DiagnosticReason` of each message "at birth", without doing any later re-classifications, which are potentially error prone, as the `DynFlags` might evolve during the course of the program. In preparation for a proper refactoring, now `pprWarning` from the Parser.Ppr module has been renamed to `mkParserWarn`, which now takes a `DynFlags` as input. We also get rid of the reclassification we were performing inside `printOrThrowWarnings`. Last but not least, this commit removes the need for reclassify inside GHC.Tc.Errors, and also simplifies the implementation of `maybeReportError`. Update Haddock submodule
* EPA : Rename ApiAnn to EPAnnAlan Zimmerman2021-03-311-1/+1
| | | | | | Follow-up from !2418, see #19579 Updates haddock submodule
* Add `MessageClass`, rework `Severity` and add `DiagnosticReason`.wip/adinapoli-message-class-new-designAlfredo Di Napoli2021-03-291-17/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Other than that: * Fix T16167,json,json2,T7478,T10637 tests to reflect the introduction of the `MessageClass` type * Remove `makeIntoWarning` * Remove `warningsToMessages` * Refactor GHC.Tc.Errors 1. Refactors GHC.Tc.Errors so that we use `DiagnosticReason` for "choices" (defer types errors, holes, etc); 2. We get rid of `reportWarning` and `reportError` in favour of a general `reportDiagnostic`. * Introduce `DiagnosticReason`, `Severity` is an enum: This big commit makes `Severity` a simple enumeration, and introduces the concept of `DiagnosticReason`, which classifies the /reason/ why we are emitting a particular diagnostic. It also adds a monomorphic `DiagnosticMessage` type which is used for generic messages. * The `Severity` is computed (for now) from the reason, statically. Later improvement will add a `diagReasonSeverity` function to compute the `Severity` taking `DynFlags` into account. * Rename `logWarnings` into `logDiagnostics` * Add note and expand description of the `mkHoleError` function
* GHC Exactprint main commitAlan Zimmerman2021-03-201-25/+26
| | | | | | | | Metric Increase: T10370 parsing001 Updates haddock submodule
* template-haskell: Add putDoc, getDoc, withDecDoc and friendsLuke Lau2021-03-101-7/+10
| | | | | | | | | | | | | | | | | | | | | | | This adds two new methods to the Quasi class, putDoc and getDoc. They allow Haddock documentation to be added to declarations, module headers, function arguments and class/type family instances, as well as looked up. It works by building up a map of names to attach pieces of documentation to, which are then added in the extractDocs function in GHC.HsToCore.Docs. However because these template haskell names need to be resolved to GHC names at the time they are added, putDoc cannot directly add documentation to declarations that are currently being spliced. To remedy this, withDecDoc/withDecsDoc wraps the operation with addModFinalizer, and provides a more ergonomic interface for doing so. Similarly, the funD_doc, dataD_doc etc. combinators provide a more ergonomic interface for documenting functions and their arguments simultaneously. This also changes ArgDocMap to use an IntMap rather than an Map Int, for efficiency. Part of the work towards #5467
* Fixes to dealing with the export of mainSimon Peyton Jones2021-03-091-303/+317
| | | | | | | | | | | | | | | | | | | | It's surprisingly tricky to deal with 'main' (#19397). This patch does quite bit of refactoring do to it right. Well, more-right anyway! The moving parts are documented in GHC.Tc.Module Note [Dealing with main] Some other oddments: * Rename tcRnExports to rnExports; no typechecking here! * rnExports now uses checkNoErrs rather than failIfErrsM; the former fails only if rnExports itself finds errors * Small improvements to tcTyThingCategory, which ultimately weren't important to the patch, but I've retained as a minor improvement.
* Fix two places where TcGblEnv was retainedMatthew Pickering2021-02-281-3/+4
| | | | Found with ghc-debug on the ManyConstructors test
* Ensure tcg_env is up-to-date when running typechecker pluginsalexbiehl2021-02-221-4/+8
|
* Improve handling of overloaded labels, literals, lists etcwip/T19154Simon Peyton Jones2021-02-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When implementing Quick Look I'd failed to remember that overloaded labels, like #foo, should be treated as a "head", so that they can be instantiated with Visible Type Application. This caused #19154. A very similar ticket covers overloaded literals: #19167. This patch fixes both problems, but (annoyingly, albeit temporarily) in two different ways. Overloaded labels I dealt with overloaded labels by buying fully into the Rebindable Syntax approach described in GHC.Hs.Expr Note [Rebindable syntax and HsExpansion]. There is a good overview in GHC.Rename.Expr Note [Handling overloaded and rebindable constructs]. That module contains much of the payload for this patch. Specifically: * Overloaded labels are expanded in the renamer, fixing #19154. See Note [Overloaded labels] in GHC.Rename.Expr. * Left and right sections used to have special code paths in the typechecker and desugarer. Now we just expand them in the renamer. This is harder than it sounds. See GHC.Rename.Expr Note [Left and right sections]. * Infix operator applications are expanded in the typechecker, specifically in GHC.Tc.Gen.App.splitHsApps. See Note [Desugar OpApp in the typechecker] in that module * ExplicitLists are expanded in the renamer, when (and only when) OverloadedLists is on. * HsIf is expanded in the renamer when (and only when) RebindableSyntax is on. Reason: the coverage checker treats HsIf specially. Maybe we could instead expand it unconditionally, and fix up the coverage checker, but I did not attempt that. Overloaded literals Overloaded literals, like numbers (3, 4.2) and strings with OverloadedStrings, were not working correctly with explicit type applications (see #19167). Ideally I'd also expand them in the renamer, like the stuff above, but I drew back on that because they can occur in HsPat as well, and I did not want to to do the HsExpanded thing for patterns. But they *can* now be the "head" of an application in the typechecker, and hence something like ("foo" @T) works now. See GHC.Tc.Gen.Head.tcInferOverLit. It's also done a bit more elegantly, rather than by constructing a new HsExpr and re-invoking the typechecker. There is some refactoring around tcShortCutLit. Ultimately there is more to do here, following the Rebindable Syntax story. There are a lot of knock-on effects: * HsOverLabel and ExplicitList no longer need funny (Maybe SyntaxExpr) fields to support rebindable syntax -- good! * HsOverLabel, OpApp, SectionL, SectionR all become impossible in the output of the typecheker, GhcTc; so we set their extension fields to Void. See GHC.Hs.Expr Note [Constructor cannot occur] * Template Haskell quotes for HsExpanded is a bit tricky. See Note [Quotation and rebindable syntax] in GHC.HsToCore.Quote. * In GHC.HsToCore.Match.viewLExprEq, which groups equal HsExprs for the purpose of pattern-match overlap checking, I found that dictionary evidence for the same type could have two different names. Easily fixed by comparing types not names. * I did quite a bit of annoying fiddling around in GHC.Tc.Gen.Head and GHC.Tc.Gen.App to get error message locations and contexts right, esp in splitHsApps, and the HsExprArg type. Tiresome and not very illuminating. But at least the tricky, higher order, Rebuilder function is gone. * Some refactoring in GHC.Tc.Utils.Monad around contexts and locations for rebindable syntax. * Incidentally fixes #19346, because we now print renamed, rather than typechecked, syntax in error mesages about applications. The commit removes the vestigial module GHC.Builtin.RebindableNames, and thus triggers a 2.4% metric decrease for test MultiLayerModules (#19293). Metric Decrease: MultiLayerModules T12545
* Fix a serious bug in roughMatchTcsSimon Peyton Jones2021-02-131-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | The roughMatchTcs function enables a quick definitely-no-match test in lookupInstEnv. Unfortunately, it didn't account for type families. This didn't matter when type families were flattened away, but now they aren't flattened it matters a lot. The fix is very easy. See INVARIANT in GHC.Core.InstEnv Note [ClsInst laziness and the rough-match fields] Fixes #19336 The change makes compiler perf worse on two very-type-family-heavy benchmarks, T9872{a,d}: T9872a(normal) ghc/alloc 2172536442.7 2216337648.0 +2.0% T9872d(normal) ghc/alloc 614584024.0 621081384.0 +1.1% (Everything else is 0.0% or at most 0.1%.) I think we just have to put up with this. Some cases were being wrongly filtered out by roughMatchTcs that might actually match, which could lead to false apartness checks. And it only affects these very type-family-heavy cases. Metric Increase: T9872a T9872d
* Refactor LoggerSylvain Henry2021-02-131-4/+6
| | | | | | | | | | | | | | | | | | | | | Before this patch, the only way to override GHC's default logging behavior was to set `log_action`, `dump_action` and `trace_action` fields in DynFlags. This patch introduces a new Logger abstraction and stores it in HscEnv instead. This is part of #17957 (avoid storing state in DynFlags). DynFlags are duplicated and updated per-module (because of OPTIONS_GHC pragma), so we shouldn't store global state in them. This patch also fixes a race in parallel "--make" mode which updated the `generatedDumps` IORef concurrently. Bump haddock submodule The increase in MultilayerModules is tracked in #19293. Metric Increase: MultiLayerModules
* Introduce the DecoratedSDoc typeAlfredo Di Napoli2021-02-011-12/+12
| | | | | This commit introduces a DecoratedSDoc type which replaces the old ErrDoc, and hopefully better reflects the intent.
* Rename ErrMsg into MsgEnvelopeAlfredo Di Napoli2021-02-011-1/+1
| | | | Updates Haddock submodule
* Remove ErrDoc and MsgDocAlfredo Di Napoli2021-02-011-12/+12
| | | | | | | | | | | | | This commit boldly removes the ErrDoc and the MsgDoc from the codebase. The former was introduced with the only purpose of classifying errors according to their importance, but a similar result can be obtained just by having a simple [SDoc], and placing bullets after each of them. On top of that I have taken the perhaps controversial decision to also banish MsgDoc, as it was merely a type alias over an SDoc and as such it wasn't offering any extra type safety. Granted, it was perhaps making type signatures slightly more "focused", but at the expense of cognitive burden: if it's really just an SDoc, let's call it with its proper name.
View Lorry Controller Status