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* Make reallyUnsafePtrEquality# levity-polymorphicsheaf2021-06-251-0/+7
| | | | fixes #17126, updates containers submodule
* Update quantified_constraints.rstChristian Takle2021-06-241-2/+2
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* There's no "errorWithCallStack", just use "error".Viktor Dukhovni2021-06-241-9/+8
| | | | | | | | There's no `errorWithCallStack`, only `errorWithStackTrace`, but the latter is now deprecated, since `error` now defaults to returning a stack strace. So rather than change this to the intended deprecated function we replace `errorWithCallStack` with `error` instead.
* Fix a typo in pattern synonyms docPotato Hatsue2021-06-221-2/+2
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* Typos, minor comment fixesKrzysztof Gogolewski2021-06-222-2/+3
| | | | | | | | | | | | | | | | | | | - Remove fstName, sndName, fstIdKey, sndIdKey - no longer used, removed from basicKnownKeyNames - Remove breakpointId, breakpointCondId, opaqueTyCon, unknownTyCon - they were used in the old implementation of the GHCi debugger - Fix typos in comments - Remove outdated comment in Lint.hs - Use 'LitRubbish' instead of 'RubbishLit' for consistency - Remove comment about subkinding - superseded by Note [Kind Constraint and kind Type] - Mention ticket ID in a linear types error message - Fix formatting in using-warnings.rst and linear-types.rst - Remove comment about 'Any' in Dynamic.hs - Dynamic now uses Typeable + existential instead of Any - Remove codeGen/should_compile/T13233.hs This was added by accident, it is not used and T13233 is already in should_fail
* Linker/darwin: Properly honour -fno-use-rpathsMatthew Pickering2021-06-202-2/+13
| | | | | | | | | | | | | The specification is now simple * On linux, use `-Xlinker -rpath -Xlinker` to set the rpath of the executable * On darwin, never use `-Xlinker -rpath -Xlinker`, always inject the rpath afterwards, see `runInjectRPaths`. * If `-fno-use-rpaths` is passed then *never* inject anything into the rpath. Fixes #20004
* Deprecate -Wmissing-monadfail-instances (#17875)Krzysztof Gogolewski2021-06-191-41/+23
| | | | | Also document deprecation of Wnoncanonical-monadfail-instances and -Wimplicit-kind-vars
* Corrected typoAriFordsham2021-06-161-1/+1
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* Reword: representation instead of levitysheaf2021-06-105-27/+43
| | | | fixes #19756, updates haddock submodule
* User's Guide: reword and fix punctuation in description of PostfixOperatorsLi-yao Xia2021-06-101-3/+3
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* Introduce `hsExprType :: HsExpr GhcTc -> Type` in the new modulewip/hsExprTypeRyan Scott2021-06-081-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | `GHC.Hs.Syn.Type` The existing `hsPatType`, `hsLPatType` and `hsLitType` functions have also been moved to this module This is a less ambitious take on the same problem that !2182 and !3866 attempt to solve. Rather than have the `hsExprType` function attempt to efficiently compute the `Type` of every subexpression in an `HsExpr`, this simply computes the overall `Type` of a single `HsExpr`. - Explicitly forbids the `SplicePat` `HsIPVar`, `HsBracket`, `HsRnBracketOut` and `HsTcBracketOut` constructors during the typechecking phase by using `Void` as the TTG extension field - Also introduces `dataConCantHappen` as a domain specific alternative to `absurd` to handle cases where the TTG extension points forbid a constructor. - Turns HIE file generation into a pure function that doesn't need access to the `DsM` monad to compute types, but uses `hsExprType` instead. - Computes a few more types during HIE file generation - Makes GHCi's `:set +c` command also use `hsExprType` instead of going through the desugarer to compute types. Updates haddock submodule Co-authored-by: Zubin Duggal <zubin.duggal@gmail.com>
* Make Logger independent of DynFlagsSylvain Henry2021-06-071-6/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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.
* Make some simple primops levity-polymorphicsheaf2021-06-041-0/+19
| | | | Fixes #17817
* users-guide: Add OverloadedRecordDot and OverloadedRecordUpdate for ghc-9.2Takenobu Tani2021-06-041-0/+9
| | | | | This patch adds OverloadedRecordDot and OverloadedRecordUpdate in 9.2.1's release note.
* Fix incorrect mention of -Wprepositive-qualified-syntax in docsThomas Winant2021-06-041-3/+1
| | | | | | | | The flag is called `-Wprepositive-qualified-module`, not `-Wprepositive-qualified-syntax`. Use the `:ghc-flag:` syntax, which would have caught the mistake in the first place.
* Driver Rework PatchMatthew Pickering2021-06-031-8/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | This patch comprises of four different but closely related ideas. The net result is fixing a large number of open issues with the driver whilst making it simpler to understand. 1. Use the hash of the source file to determine whether the source file has changed or not. This makes the recompilation checking more robust to modern build systems which are liable to copy files around changing their modification times. 2. Remove the concept of a "stable module", a stable module was one where the object file was older than the source file, and all transitive dependencies were also stable. Now we don't rely on the modification time of the source file, the notion of stability is moot. 3. Fix TH/plugin recompilation after the removal of stable modules. The TH recompilation check used to rely on stable modules. Now there is a uniform and simple way, we directly track the linkables which were loaded into the interpreter whilst compiling a module. This is an over-approximation but more robust wrt package dependencies changing. 4. Fix recompilation checking for dynamic object files. Now we actually check if the dynamic object file exists when compiling with -dynamic-too Fixes #19774 #19771 #19758 #17434 #11556 #9121 #8211 #16495 #7277 #16093
* Add -Wmissing-exported-pattern-synonym-signaturesThomas Winant2021-05-291-0/+18
| | | | | | | | | | | | | After !4741, it was no longer possible to silence a warning about a missing pattern synonym signature if the `-Wmissing-signatures` flag was on. Restore the previous semantics while still adhering to the principle "enabling an additional warning flag should never make prior warnings disappear". For more symmetry and granularity, introduce `-Wmissing-exported-pattern-synonym-signatures`. See Note [Missing signatures] for an overview of all flags involved.
* Document release when TypeApplications allowed declaring variables as inferredBoris Lykah2021-05-281-2/+3
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* Enable strict dicts by default at -O2.Andreas Klebinger2021-05-271-1/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the common case this is a straight performance win at a compile time cost so we enable it at -O2. In rare cases it can lead to compile time regressions because of changed inlining behaviour. Which can very rarely also affect runtime performance. Increasing the inlining threshold can help to avoid this which is documented in the user guide. In terms of measured results this reduced instructions executed for nofib by 1%. However for some cases (e.g. Cabal) enabling this by default increases compile time by 2-3% so we enable it only at -O2 where it's clear that a user is willing to trade compile time for runtime. Most of the testsuite runs without -O2 so there are few perf changes. Increases: T12545/T18698: We perform more WW work because dicts are now treated strict. T9198: Also some more work because functions are now subject to W/W Decreases: T14697: Compiling empty modules. Probably because of changes inside ghc. T9203: I can't reproduce this improvement locally. Might be spurious. ------------------------- Metric Decrease: T12227 T14697 T9203 Metric Increase: T9198 T12545 T18698a T18698b -------------------------
* Add 9.2 release note about linear caseRichard Eisenberg2021-05-251-0/+6
| | | | | | This is part of #18738 [skip ci]
* base: Update Unicode data to 13.0.0Ben Gamari2021-05-111-0/+2
| | | | (cherry picked from commit d22e087f7bf74341c4468f11b4eb0273033ca931)
* Redesign withDict (formerly magicDict)Ryan Scott2021-04-292-0/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This gives a more precise type signature to `magicDict` as proposed in #16646. In addition, this replaces the constant-folding rule for `magicDict` in `GHC.Core.Opt.ConstantFold` with a special case in the desugarer in `GHC.HsToCore.Expr.dsHsWrapped`. I have also renamed `magicDict` to `withDict` in light of the discussion in https://mail.haskell.org/pipermail/ghc-devs/2021-April/019833.html. All of this has the following benefits: * `withDict` is now more type safe than before. Moreover, if a user applies `withDict` at an incorrect type, the special-casing in `dsHsWrapped` will now throw an error message indicating what the user did incorrectly. * `withDict` can now work with classes that have multiple type arguments, such as `Typeable @k a`. This means that `Data.Typeable.Internal.withTypeable` can now be implemented in terms of `withDict`. * Since the special-casing for `withDict` no longer needs to match on the structure of the expression passed as an argument to `withDict`, it no longer cares about the presence or absence of `Tick`s. In effect, this obsoletes the fix for #19667. The new `T16646` test case demonstrates the new version of `withDict` in action, both in terms of `base` functions defined in terms of `withDict` as well as in terms of functions from the `reflection` and `singletons` libraries. The `T16646Fail` test case demonstrates the error message that GHC throws when `withDict` is applied incorrectly. This fixes #16646. By adding more tests for `withDict`, this also fixes #19673 as a side effect.
* 19079 DerivingVia: incorrectly accepts deriving via types with differing ↵Sasha Bogicevic2021-04-271-3/+5
| | | | runtime representations
* Introduce -ddump-verbose-inliningsBen Gamari2021-04-271-5/+10
| | | | | | | | Previously -ddump-inlinings and -dverbose-core2core used in conjunction would have the side-effect of dumping additional information about all inlinings considered by the simplifier. However, I have sometimes wanted this inlining information without the firehose of information produced by -dverbose-core2core. Introduce a new dump flag for this purpose.
* docs: add a short up-front description for -O, -n, -qn, -I and -IwAdam Sandberg Ericsson2021-04-261-10/+19
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* users guide: Various other cleanupsBen Gamari2021-04-262-10/+26
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* users-guide: Document deprecation of -funfolding-keeness-factorBen Gamari2021-04-263-1/+16
| | | | See #15304.
* Worker/wrapper: Consistent namesSebastian Graf2021-04-201-1/+1
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* users-guide: Add missing FieldSelectors to GHC2021 listBen Gamari2021-04-181-0/+1
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* users guide: Sort lists of implied language extensionsBen Gamari2021-04-181-20/+20
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* users-guide: Clarify GHC2021 documentationBen Gamari2021-04-181-1/+7
| | | | | Point out that GHC2021 doesn't offer the same degree of stability that Haskell2010 does, as noted by @phadej.
* Only load package environment file once when starting GHCiMatthew Pickering2021-04-181-0/+4
| | | | | | | | | | | | | | | Since d880d6b2e48268f5ed4d3eb751fe24cc833e9221 the parsing of the environment files was moved to `parseDynamicFlags`, under the assumption it was typically only called once. It turns out not to be true in GHCi and this led to continually reparsing the environment file whenever a new option was set, the options were appended to the package state and hence all packages reloaded, as it looked like the options were changed. The simplest fix seems to be a clearer specification: > Package environment files are only loaded in GHCi during initialisation. Fixes #19650
* [docs] release notes for !4729 + !3678Douglas Wilson2021-04-091-1/+33
| | | | Also includes small unrelated type fix
* Implement proposal 403: Lexer cleanupOleg Grenrus2021-04-051-0/+21
| | | | | This allows Other Numbers to be used in identifiers, and also documents other, already existing lexer divergence from Haskell Report
* Data.List specialization to []Oleg Grenrus2021-04-011-7/+2
| | | | | | | - Remove GHC.OldList - Remove Data.OldList - compat-unqualified-imports is no-op - update haddock submodule
* users-guide: Correct markdown for ghc-9.2Takenobu Tani2021-03-303-7/+7
| | | | | | This patch corrects some markdown. [skip ci]
* Allocate Adjustors and mark them readable in two stepsMoritz Angermann2021-03-291-1/+1
| | | | | | | | | This drops allocateExec for darwin, and replaces it with a alloc, write, mark executable strategy instead. This prevents us from trying to allocate an executable range and then write to it, which X^W will prohibit on darwin. This will *only* work if we can use mmap.
* Implement -Wmissing-kind-signaturesOleg Grenrus2021-03-251-0/+27
| | | | Fixes #19564
* More improvement to MonoLocalBinds documentationSimon Peyton Jones2021-03-231-50/+35
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* Built-in type families: CharToNat, NatToChar (#19535)Vladislav Zavialov2021-03-171-0/+2
| | | | | Co-authored-by: Daniel Rogozin <daniel.rogozin@serokell.io> Co-authored-by: Rinat Stryungis <rinat.stryungis@serokell.io>
* Document how GADT patterns are matched from left-to-right, outside-inRyan Scott2021-03-171-1/+82
| | | | | | | | | | | | | | This adds some bullet points to the GHC User's Guide section on `GADTs` to explain some subtleties in how GHC typechecks GADT patterns. In particular, this adds examples of programs being rejected for matching on GADTs in a way that does not mesh with GHC's left-to-right, outside-in order for checking patterns, which can result in programs being rejected for seemingly counterintuitive reasons. (See #12018 for examples of confusion that arose from this.) In addition, now that we have visible type application in data constructor patterns, I mention a possible workaround of using `TypeApplications` to repair programs of this sort. Resolves #12018.
* Document the interaction between ScopedTypeVariables and ↵Ryan Scott2021-03-151-0/+31
| | | | | | | | | StandaloneKindSignatures This documents a limitation of `StandaloneKindSignatures`—namely, that it does not bring type variables bound by an outermost `forall` into scope over a type-level declaration—in the GHC User's Guide. See #19498 for more discussion.
* Correct module name in `-fprof-callers` documentationMatthew Pickering2021-03-141-1/+1
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* Implement the UnliftedDatatypes extensionSebastian Graf2021-03-142-4/+113
| | | | | | | | | | | | | | | | | | GHC Proposal: 0265-unlifted-datatypes.rst Discussion: https://github.com/ghc-proposals/ghc-proposals/pull/265 Issues: https://gitlab.haskell.org/ghc/ghc/-/issues/19523 Implementation Details: Note [Implementation of UnliftedDatatypes] This patch introduces the `UnliftedDatatypes` extension. When this extension is enabled, GHC relaxes the restrictions around what result kinds are allowed in data declarations. This allows data types for which an unlifted or levity-polymorphic result kind is inferred. The most significant changes are in `GHC.Tc.TyCl`, where `Note [Implementation of UnliftedDatatypes]` describes the details of the implementation. Fixes #19523.
* Ignore breakpoint for a specified number of iterations. (#19157)Roland Senn2021-03-102-7/+34
| | | | | | | | | | | | | | | | * Implement new debugger command `:ignore` to set an `ignore count` for a specified breakpoint. * Allow new optional parameter on `:continue` command to set an `ignore count` for the current breakpoint. * In the Interpreter replace the current `Word8` BreakArray with an `Int` array. * Change semantics of values in `BreakArray` to: n < 0 : Breakpoint is disabled. n == 0 : Breakpoint is enabled. n > 0 : Breakpoint is enabled, but ignore next `n` iterations. * Rewrite `:enable`/`:disable` processing as a special case of `:ignore`. * Remove references to `BreakArray` from `ghc/UI.hs`.
* Use GHC2021 as default languageJoachim Breitner2021-03-101-4/+5
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* Introduce GHC2021 languageJoachim Breitner2021-03-103-19/+87
| | | | | | This adds support for -XGHC2021, as described in Proposal 0380 [1]. [1] https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0380-ghc2021.rst
* template-haskell: Add putDoc, getDoc, withDecDoc and friendsLuke Lau2021-03-101-0/+13
| | | | | | | | | | | | | | | | | | | | | | | 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
* rts: Gradually return retained memory to the OSMatthew Pickering2021-03-102-2/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Related to #19381 #19359 #14702 After a spike in memory usage we have been conservative about returning allocated blocks to the OS in case we are still allocating a lot and would end up just reallocating them. The result of this was that up to 4 * live_bytes of blocks would be retained once they were allocated even if memory usage ended up a lot lower. For a heap of size ~1.5G, this would result in OS memory reporting 6G which is both misleading and worrying for users. In long-lived server applications this results in consistent high memory usage when the live data size is much more reasonable (for example ghcide) Therefore we have a new (2021) strategy which starts by retaining up to 4 * live_bytes of blocks before gradually returning uneeded memory back to the OS on subsequent major GCs which are NOT caused by a heap overflow. Each major GC which is NOT caused by heap overflow increases the consec_idle_gcs counter and the amount of memory which is retained is inversely proportional to this number. By default the excess memory retained is oldGenFactor (controlled by -F) / 2 ^ (consec_idle_gcs * returnDecayFactor) On a major GC caused by a heap overflow, the `consec_idle_gcs` variable is reset to 0 (as we could continue to allocate more, so retaining all the memory might make sense). Therefore setting bigger values for `-Fd` makes the rate at which memory is returned slower. Smaller values make it get returned faster. Setting `-Fd0` disables the memory return completely, which is the behaviour of older GHC versions. The default is `-Fd4` which results in the following scaling: > mapM print [(x, 1/ (2**(x / 4))) | x <- [1 :: Double ..20]] (1.0,0.8408964152537146) (2.0,0.7071067811865475) (3.0,0.5946035575013605) (4.0,0.5) (5.0,0.4204482076268573) (6.0,0.35355339059327373) (7.0,0.29730177875068026) (8.0,0.25) (9.0,0.21022410381342865) (10.0,0.17677669529663687) (11.0,0.14865088937534013) (12.0,0.125) (13.0,0.10511205190671433) (14.0,8.838834764831843e-2) (15.0,7.432544468767006e-2) (16.0,6.25e-2) (17.0,5.255602595335716e-2) (18.0,4.4194173824159216e-2) (19.0,3.716272234383503e-2) (20.0,3.125e-2) So after 13 consecutive GCs only 0.1 of the maximum memory used will be retained. Further to this decay factor, the amount of memory we attempt to retain is also influenced by the GC strategy for the oldest generation. If we are using a copying strategy then we will need at least 2 * live_bytes for copying to take place, so we always keep that much. If using compacting or nonmoving then we need a lower number, so we just retain at least `1.2 * live_bytes` for some protection. In future we might want to make this behaviour more aggressive, some relevant literature is > Ulan Degenbaev, Jochen Eisinger, Manfred Ernst, Ross McIlroy, and Hannes Payer. 2016. Idle time garbage collection scheduling. SIGPLAN Not. 51, 6 (June 2016), 570–583. DOI:https://doi.org/10.1145/2980983.2908106 which describes the "memory reducer" in the V8 javascript engine which on an idle collection immediately returns as much memory as possible.
* Document operator sections' interaction with subsumptionRyan Scott2021-03-092-0/+19
| | | | | | This resolves #19457 by making a note of breaking changes (introduced in GHC 9.2) to the way that GHC typechecks operator sections where the operator has nested `forall`s or contexts in its type signature.
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