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* Fixes to 9.4 release notesKrzysztof Gogolewski2022-04-083-10/+22
| | | | | | - Mention -Wforall-identifier - Improve description of withDict - Fix formatting
* Properly explain where INLINE pragmas can appear.Andreas Klebinger2022-04-071-6/+41
| | | | Fixes #20676
* Add warnings for file header pragmas that appear in the body of a module ↵Zubin Duggal2022-04-061-0/+14
| | | | | | | | | | | | | | | (#20385) Once we are done parsing the header of a module to obtain the options, we look through the rest of the tokens in order to determine if they contain any misplaced file header pragmas that would usually be ignored, potentially resulting in bad error messages. The warnings are reported immediately so that later errors don't shadow over potentially helpful warnings. Metric Increase: T13719
* users-guide: Fix various markup issuesBen Gamari2022-04-011-15/+15
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* Implement \cases (Proposal 302)Jakob Bruenker2022-04-013-5/+25
| | | | | | | | | | | | This commit implements proposal 302: \cases - Multi-way lambda expressions. This adds a new expression heralded by \cases, which works exactly like \case, but can match multiple apats instead of a single pat. Updates submodule haddock to support the ITlcases token. Closes #20768
* Keep track of promotion ticks in HsOpTywip/no-c-stubswip/matt-merge-batchsheaf2022-04-012-0/+11
| | | | | | | | | | | | | | | | This patch adds a PromotionFlag field to HsOpTy, which is used in pretty-printing and when determining whether to emit warnings with -fwarn-unticked-promoted-constructors. This allows us to correctly report tick-related warnings for things like: type A = Int : '[] type B = [Int, Bool] Updates haddock submodule Fixes #19984
* docs: Update documentation interaction of search path, -hidir and -c mode.Matthew Pickering2022-04-011-5/+9
| | | | | | | | | As noted in #20569 the documentation for search path was wrong because it seemed to indicate that `-i` dirs were important when looking for interface files in `-c` mode, but they are not important if `-hidir` is set. Fixes #20569
* Change GHC.Prim to GHC.Exts in docs and testsKrzysztof Gogolewski2022-04-013-5/+4
| | | | | Users are supposed to import GHC.Exts rather than GHC.Prim. Part of #18749.
* Add tests and docs on plugin args and order.Phil de Joux2022-04-011-1/+30
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* Clarify that runghc interprets the input programMorrow2022-04-011-2/+2
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* new datatypes for parsedResultActionJakob Bruenker2022-04-012-27/+29
| | | | | | | | Previously, the warnings and errors were given and returned as a tuple (Messages PsWarnings, Messages PsErrors). Now, it's just PsMessages. This, together with the HsParsedModule the parser plugin gets and returns, has been wrapped up as ParsedResult.
* users-guide: Fix a few small issues in eventlog format descriptionsBen Gamari2022-04-011-1/+2
| | | | | The CONC_MARK_END event description didn't mention its payload. Clarify the meaning of the CREATE_TASK's payload.
* Give parsing plugins access to errorsJakob Brünker2022-03-302-7/+30
| | | | | | | | | | | Previously, when the parser produced non-fatal errors (i.e. it produced errors but the 'PState' is 'POk'), compilation would be aborted before the 'parsedResultAction' of any plugin was invoked. This commit changes that, so that such that 'parsedResultAction' gets collections of warnings and errors as argument, and must return them after potentially modifying them. Closes #20803
* users-guide: group ticky-ticky profiling under one headingAdam Sandberg Ericsson2022-03-281-5/+5
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* Document typed splices inhibiting unused bind detection (#16524)jberryman2022-03-281-0/+3
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* users-guide: Correct markdown for profilingTakenobu Tani2022-03-281-5/+6
| | | | | | This patch corrects some markdown. [skip ci]
* Add the OPAQUE pragmaChristiaan Baaij2022-03-252-0/+27
| | | | | | | | | | | | A new pragma, `OPAQUE`, that ensures that every call of a named function annotated with an `OPAQUE` pragma remains a call of that named function, not some name-mangled variant. Implements GHC proposal 0415: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0415-opaque-pragma.rst This commit also updates the haddock submodule to handle the newly introduced lexer tokens corresponding to the OPAQUE pragma.
* Fix behaviour of -Wunused-packages in ghciMatthew Pickering2022-03-231-5/+9
| | | | | | | | | | | | | | | | | Ticket #21110 points out that -Wunused-packages behaves a bit unusually in GHCi. Now we define the semantics for -Wunused-packages in interactive mode as follows: * If you use -Wunused-packages on an initial load then the warning is reported. * If you explicitly set -Wunused-packages on the command line then the warning is displayed (until it is disabled) * If you then subsequently modify the set of available targets by using :load or :cd (:cd unloads everything) then the warning is (silently) turned off. This means that every :r the warning is printed if it's turned on (but you did ask for it). Fixes #21110
* docs: clarify the eventlog format documentation a little bitAdam Sandberg Ericsson2022-03-231-14/+15
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* Export (~) from Data.Type.Equality (#18862)wip/eqtycon-rnVladislav Zavialov2022-03-152-3/+62
| | | | | | | | | | * Users can define their own (~) type operator * Haddock can display documentation for the built-in (~) * New transitional warnings implemented: -Wtype-equality-out-of-scope -Wtype-equality-requires-operators Updates the haddock submodule.
* Worker/wrapper: Preserve float barriers (#21150)Sebastian Graf2022-03-131-2/+11
| | | | | | | | | | | | | | | | | | | | | | | Issue #21150 shows that worker/wrapper allocated a worker function for a function with multiple calls that said "called at most once" when the first argument was absent. That's bad! This patch makes it so that WW preserves at least one non-one-shot value lambda (see `Note [Preserving float barriers]`) by passing around `void#` in place of absent arguments. Fixes #21150. Since the fix is pretty similar to `Note [Protecting the last value argument]`, I put the logic in `mkWorkerArgs`. There I realised (#21204) that `-ffun-to-thunk` is basically useless with `-ffull-laziness`, so I deprecated the flag, simplified and split into `needsVoidWorkerArg`/`addVoidWorkerArg`. SpecConstr is another client of that API. Fixes #21204. Metric Decrease: T14683
* Rename -fprof-late-ccs to -fprof-lateAndreas Klebinger2022-03-122-3/+3
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* Always generalise top-level bindingsSimon Peyton Jones2022-03-071-17/+25
| | | | | Fix #21023 by always generalising top-level binding; change the documentation of -XMonoLocalBinds to match.
* Update documentation of LiberalTypeSynonymsKrzysztof Gogolewski2022-03-041-21/+1
| | | | | | | | | We no longer require LiberalTypeSynonyms to use 'forall' or an unboxed tuple in a synonym. I also removed that kind checking before expanding synonyms "could be changed". This was true when type synonyms were thought of macros, but with the extensions such as SAKS or matchability I don't see it changing.
* docs: Add note to RULES documentation about locally bound variables [skip ci]Matthew Pickering2022-03-031-0/+25
| | | | Fixes #20100
* Improve out-of-order inferred type variablessheaf2022-03-022-15/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't instantiate type variables for :type in `GHC.Tc.Gen.App.tcInstFun`, to avoid inconsistently instantianting `r1` but not `r2` in the type forall {r1} (a :: TYPE r1) {r2} (b :: TYPE r2). ... This fixes #21088. This patch also changes the primop pretty-printer to ensure that we put all the inferred type variables first. For example, the type of reallyUnsafePtrEquality# is now forall {l :: Levity} {k :: Levity} (a :: TYPE (BoxedRep l)) (b :: TYPE (BoxedRep k)). a -> b -> Int# This means we avoid running into issue #21088 entirely with the types of primops. Users can still write a type signature where the inferred type variables don't come first, however. This change to primops had a knock-on consequence, revealing that we were sometimes performing eta reduction on keepAlive#. This patch updates tryEtaReduce to avoid eta reducing functions with no binding, bringing it in line with tryEtaReducePrep, and thus fixing #21090.
* Ticky profiling improvements.Matthew Pickering2022-03-021-0/+148
| | | | | | | | | | | | | | | | | | | | This adds a number of changes to ticky-ticky profiling. When an executable is profiled with IPE profiling it's now possible to associate id-related ticky counters to their source location. This works by emitting the info table address as part of the counter which can be looked up in the IPE table. Add a `-ticky-ap-thunk` flag. This flag prevents the use of some standard thunks which are precompiled into the RTS. This means reduced cache locality and increased code size. But it allows better attribution of execution cost to specific source locations instead of simple attributing it to the standard thunk. ticky-ticky now uses the `arg` field to emit additional information about counters in json format. When ticky-ticky is used in combination with the eventlog eventlog2html can be used to generate a html table from the eventlog similar to the old text output for ticky-ticky.
* Ticky: Gate tag-inference dummy ticky-counters behind a flag.Andreas Klebinger2022-02-252-1/+25
| | | | | | | | | | Tag inference included a way to collect stats about avoided tag-checks. This was dony by emitting "dummy" ticky entries with counts corresponding to predicted/unpredicated tag checks. This behaviour for ticky is now gated behind -fticky-tag-checks. I also documented ticky-LNE in the process.
* GHCi: don't normalise partially instantiated typessheaf2022-02-251-1/+7
| | | | | | | | | This patch skips performing type normalisation when we haven't fully instantiated the type. That is, in tcRnExpr (used only for :type in GHCi), skip normalisation if the result type responds True to isSigmaTy. Fixes #20974
* Kill derived constraintsRichard Eisenberg2022-02-231-0/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Co-authored by: Sam Derbyshire Previously, GHC had three flavours of constraint: Wanted, Given, and Derived. This removes Derived constraints. Though serving a number of purposes, the most important role of Derived constraints was to enable better error messages. This job has been taken over by the new RewriterSets, as explained in Note [Wanteds rewrite wanteds] in GHC.Tc.Types.Constraint. Other knock-on effects: - Various new Notes as I learned about under-described bits of GHC - A reshuffling around the AST for implicit-parameter bindings, with better integration with TTG. - Various improvements around fundeps. These were caused by the fact that, previously, fundep constraints were all Derived, and Derived constraints would get dropped. Thus, an unsolved Derived didn't stop compilation. Without Derived, this is no longer possible, and so we have to be considerably more careful around fundeps. - A nice little refactoring in GHC.Tc.Errors to center the work on a new datatype called ErrorItem. Constraints are converted into ErrorItems at the start of processing, and this allows for a little preprocessing before the main classification. - This commit also cleans up the behavior in generalisation around functional dependencies. Now, if a variable is determined by functional dependencies, it will not be quantified. This change is user facing, but it should trim down GHC's strange behavior around fundeps. - Previously, reportWanteds did quite a bit of work, even on an empty WantedConstraints. This commit adds a fast path. - Now, GHC will unconditionally re-simplify constraints during quantification. See Note [Unconditionally resimplify constraints when quantifying], in GHC.Tc.Solver. Close #18398. Close #18406. Solve the fundep-related non-confluence in #18851. Close #19131. Close #19137. Close #20922. Close #20668. Close #19665. ------------------------- Metric Decrease: LargeRecord T9872b T9872b_defer T9872d TcPlugin_RewritePerf -------------------------
* docs: fix error in annotation guide code snippetHugo2022-02-221-2/+2
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* Remove -Wunticked-promoted-constructors from -WallKrzysztof Gogolewski2022-02-227-55/+60
| | | | | | | Update manual; explain ticks as optional disambiguation rather than the preferred default. This is a part of #20531.
* Track object file dependencies for TH accurately (#20604)Zubin Duggal2022-02-201-0/+18
| | | | | | | | | | | | | | | | | | | `hscCompileCoreExprHook` is changed to return a list of `Module`s required by a splice. These modules are accumulated in the TcGblEnv (tcg_th_needed_mods). Dependencies on the object files of these modules are recording in the interface. The data structures in `LoaderState` are replaced with more efficient versions to keep track of all the information required. The MultiLayerModulesTH_Make allocations increase slightly but runtime is faster. Fixes #20604 ------------------------- Metric Increase: MultiLayerModulesTH_Make -------------------------
* docs: fix release notes formattingAdam Sandberg Ericsson2022-02-161-16/+17
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* docs: mention -fprof-late-ccs in the release notesAdam Sandberg Ericsson2022-02-162-0/+5
| | | | And note which compiler version it was added in.
* Tag inference work.Andreas Klebinger2022-02-123-0/+73
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This does three major things: * Enforce the invariant that all strict fields must contain tagged pointers. * Try to predict the tag on bindings in order to omit tag checks. * Allows functions to pass arguments unlifted (call-by-value). The former is "simply" achieved by wrapping any constructor allocations with a case which will evaluate the respective strict bindings. The prediction is done by a new data flow analysis based on the STG representation of a program. This also helps us to avoid generating redudant cases for the above invariant. StrictWorkers are created by W/W directly and SpecConstr indirectly. See the Note [Strict Worker Ids] Other minor changes: * Add StgUtil module containing a few functions needed by, but not specific to the tag analysis. ------------------------- Metric Decrease: T12545 T18698b T18140 T18923 LargeRecord Metric Increase: LargeRecord ManyAlternatives ManyConstructors T10421 T12425 T12707 T13035 T13056 T13253 T13253-spj T13379 T15164 T18282 T18304 T18698a T1969 T20049 T3294 T4801 T5321FD T5321Fun T783 T9233 T9675 T9961 T19695 WWRec -------------------------
* Fix copy-pasto in prof-late-ccs docsMatthew Pickering2022-02-101-2/+2
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* Docs:Mention that safe calls don't keep their arguments alive.Andreas Klebinger2022-02-101-2/+9
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* Add late cost centre supportAndreas Klebinger2022-02-101-0/+13
| | | | | This allows cost centres to be inserted after the core optimization pipeline has run.
* Rename -merge-objs flag to --merge-objsBen Gamari2022-02-092-2/+2
| | | | For consistency with --make and friends.
* Rewrite CallerCC parser using ReadPMatthew Pickering2022-02-031-2/+2
| | | | | | | | | | This allows us to remove the dependency on parsec and hence transitively on text. Also added some simple unit tests for the parser and fixed two small issues in the documentation. Fixes #21033
* Improve migration strategy for the XDG compliance change to the GHC applicationZubin Duggal2022-01-311-0/+19
| | | | | | | | | | | directory. We want to always use the old path (~/.ghc/..) if it exists. But we never want to create the old path. This ensures that the migration can eventually be completed once older GHC versions are no longer in circulation. Fixes #20684, #20669, #20660
* rel-notes: Note dropping of SPARC supportBen Gamari2022-01-291-0/+2
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* CmmToAsm: Drop ncgExpandTopBen Gamari2022-01-291-6/+0
| | | | This was only needed for SPARC's synthetic instructions.
* users-guide: Document GHC_CHARENC environment variableBen Gamari2022-01-271-4/+10
| | | | | | | As noted in #20963, this was introduced in 1b56c40578374a15b4a2593895710c68b0e2a717 but was no documentation was added at that point. Closes #20963.
* Re #18087 user's guide: add a note that -Wxxx used to be -fwarn-xxxAndreas Abel2022-01-271-0/+7
| | | | | | | | | The warning option syntax -W was introduced in GHC 8. The note should clarify what e.g. "since 7.6" means in connection with "-Wxxx": That "-fwarn-xxx" was introduced in 7.6.1. [ci skip]
* Ctd. #18087: complete :since: info for all warnings in users guideAndreas Abel2022-01-272-0/+36
| | | | | | | | Some warnings have been there "forever" and I could not trace back the exact genesis, so I wrote "since at least 5.04". The flag `helpful-errors` could have been added in 7.2 already. I wrote 7.4 since I have no 7.2 available and it is not recognized by 7.0.
* Levity-polymorphic arrays and mutable variablessheaf2022-01-261-8/+119
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch makes the following types levity-polymorphic in their last argument: - Array# a, SmallArray# a, Weak# b, StablePtr# a, StableName# a - MutableArray# s a, SmallMutableArray# s a, MutVar# s a, TVar# s a, MVar# s a, IOPort# s a The corresponding primops are also made levity-polymorphic, e.g. `newArray#`, `readArray#`, `writeMutVar#`, `writeIOPort#`, etc. Additionally, exception handling functions such as `catch#`, `raise#`, `maskAsyncExceptions#`,... are made levity/representation-polymorphic. Now that Array# and MutableArray# also work with unlifted types, we can simply re-define ArrayArray# and MutableArrayArray# in terms of them. This means that ArrayArray# and MutableArrayArray# are no longer primitive types, but simply unlifted newtypes around Array# and MutableArrayArray#. This completes the implementation of the Pointer Rep proposal https://github.com/ghc-proposals/ghc-proposals/pull/203 Fixes #20911 ------------------------- Metric Increase: T12545 ------------------------- ------------------------- Metric Decrease: T12545 -------------------------
* linksEric Lindblad2022-01-241-2/+2
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* Add -fcompact-unwindRobert Hensing2022-01-241-0/+14
| | | | | | | | | | | | | | | | | | | | | | | | This gives users the choice to enable __compact_unwind sections when linking. These were previously hardcoded to be removed. This can be used to solved the problem "C++ does not catch exceptions when used with Haskell-main and linked by ghc", https://gitlab.haskell.org/ghc/ghc/-/issues/11829 It does not change the default behavior, because I can not estimate the impact this would have. When Apple first introduced the compact unwind ABI, a number of open source projects have taken the easy route of disabling it, avoiding errors or even just warnings shortly after its introduction. Since then, about a decade has passed, so it seems quite possible that Apple itself, and presumably many programs with it, have successfully switched to the new format, to the point where the old __eh_frame section support is in disrepair. Perhaps we should get along with the program, but for now we can test the waters with this flag, and use it to fix packages that need it.
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