Zubin pushed to branch wip/26264 at Glasgow Haskell Compiler / GHC Commits: 7471eb6a by sheaf at 2025-10-07T21:39:43-04:00 Improve how we detect user type errors in types This commit cleans up all the code responsible for detecting whether a type contains "TypeError msg" applications nested inside it. All the logic is now in 'userTypeError_maybe', which is always deep. Whether it looks inside type family applications is determined by the passed-in boolean flag: - When deciding whether a constraint is definitely insoluble, don't look inside type family applications, as they may still reduce -- in which case the TypeError could disappear. - When reporting unsolved constraints, look inside type family applications: they had the chance to reduce but didn't, and the custom type error might contain valuable information. All the details are explained in Note [Custom type errors in constraints] in GHC.Tc.Types.Constraint. Another benefit of this change is that it allows us to get rid of the deeply dodgy 'getUserTypeErrorMsg' function. This commit also improves the detection of custom type errors, for example in equality constraints: TypeError blah ~# rhs It used to be the case that we didn't detect the TypeError on the LHS, because we never considered that equality constraints could be insoluble due to the presence of custom type errors. Addressing this oversight improves detection of redundant pattern match warnings, fixing #26400. - - - - - 29955267 by Rodrigo Mesquita at 2025-10-07T21:40:25-04:00 cleanup: Drop obsolete settings from config.mk.in These values used to be spliced into the bindist's `config.mk` s.t. when `make` was run, the values were read and written into the bindist installation `settings` file. However, we now carry these values to the bindist directly in the default.target toolchain file, and `make` writes almost nothing to `settings` now (see #26227) The entries deleted in this MR were already unused. Fixes #26478 - - - - - f7adfed2 by ARATA Mizuki at 2025-10-08T08:37:24-04:00 T22033 is only relevant if the word size is 64-bit Fixes #25497 - - - - - ff1650c9 by Ben Gamari at 2025-10-08T08:38:07-04:00 rts/posix: Enforce iteration limit on heap reservation logic Previously we could loop indefinitely when attempting to get an address space reservation for our heap. Limit the logic to 8 iterations to ensure we instead issue a reasonable error message. Addresses #26151. - - - - - 01844557 by Ben Gamari at 2025-10-08T08:38:07-04:00 rts/posix: Hold on to low reservations when reserving heap Previously when the OS gave us an address space reservation in low memory we would immediately release it and try again. However, on some platforms this meant that we would get the same allocation again in the next iteration (since mmap's `hint` argument is just that, a hint). Instead we now hold on to low reservations until we have found a suitable heap reservation. Fixes #26151. - - - - - b2c8d052 by Sven Tennie at 2025-10-08T08:38:47-04:00 Build terminfo only in upper stages in cross-builds (#26288) Currently, there's no way to provide library paths for [n]curses for both - build and target - in cross-builds. As stage0 is only used to build upper stages, it should be fine to build terminfo only for them. This re-enables building cross-compilers with terminfo. - - - - - c58f9a61 by Julian Ospald at 2025-10-08T08:39:36-04:00 ghc-toolchain: Drop `ld.gold` from merge object command It's deprecated. Also see #25716 - - - - - 2b8baada by sheaf at 2025-10-08T18:23:37-04:00 Improvements to 'mayLookIdentical' This commit makes significant improvements to the machinery that decides when we should pretty-print the "invisible bits" of a type, such as: - kind applications, e.g. '@k' in 'Proxy @k ty' - RuntimeReps, e.g. 'TYPE r' - multiplicities and linear arrows 'a %1 -> b' To do this, this commit refactors 'mayLookIdentical' to return **which** of the invisible bits don't match up, e.g. in (a %1 -> b) ~ (a %Many -> b) we find that the invisible bit that doesn't match up is a multiplicity, so we should set 'sdocLinearTypes = True' when pretty-printing, and with e.g. Proxy @k1 ~ Proxy @k2 we find that the invisible bit that doesn't match up is an invisible TyCon argument, so we set 'sdocPrintExplicitKinds = True'. We leverage these changes to remove the ad-hoc treatment of linearity of data constructors with 'dataConDisplayType' and 'dataConNonLinearType'. This is now handled by the machinery of 'pprWithInvisibleBits'. Fixes #26335 #26340 - - - - - 129ce32d by sheaf at 2025-10-08T18:23:37-04:00 Store SDoc context in SourceError This commits modifies the SourceError datatype which is used for throwing and then reporting exceptions by storing all the info we need to be able to print the SDoc, including whether we should print with explicit kinds, explicit runtime-reps, etc. This is done using the new datatype: data SourceErrorContext = SEC !DiagOpts !(DiagnosticOpts GhcMessage) Now, when we come to report an error (by handling the exception), we have access to the full context we need. Fixes #26387 - - - - - f9790ca8 by Ben Gamari at 2025-10-08T18:24:19-04:00 gitlab-ci: Make RELEASE_JOB an input Rather than an undocumented variable. - - - - - 14281a22 by Ben Gamari at 2025-10-11T14:06:47-04:00 rts/nonmoving: Fix comment spelling - - - - - bedd38b0 by Ben Gamari at 2025-10-11T14:06:47-04:00 rts/nonmoving: Use atomic operations to update bd->flags - - - - - 215d6841 by Ben Gamari at 2025-10-11T14:06:47-04:00 nonmoving: Use get_itbl instead of explicit loads This is cleaner and also fixes unnecessary (and unsound) use of `volatile`. - - - - - 2c94aa3a by Ben Gamari at 2025-10-11T14:06:47-04:00 rts/Scav: Handle WHITEHOLEs in scavenge_one `scavenge_one`, used to scavenge mutable list entries, may encounter `WHITEHOLE`s when the non-moving GC is in use via two paths: 1. when an MVAR is being marked concurrently 2. when the object belongs to a chain of selectors being short-cutted. Fixes #26204. - - - - - 6bd8155c by Matthew Pickering at 2025-10-11T14:07:29-04:00 Add support for generating bytecode objects This commit adds the `-fwrite-byte-code` option which makes GHC emit a `.gbc` file which contains a serialised representation of bytecode. The bytecode can be loaded by the compiler to avoid having to reinterpret a module when using the bytecode interpreter (for example, in GHCi). There are also the new options: * -gbcdir=<DIR>: Specify the directory to place the gbc files * -gbcsuf=<suffix>: Specify the suffix for gbc files The option `-fbyte-code-and-object-code` now implies `-fwrite-byte-code`. These performance tests fail due to https://github.com/haskell/directory/issues/204 ------------------------- Metric Increase: MultiComponentModules MultiLayerModules MultiComponentModulesRecomp MultiLayerModulesRecomp MultiLayerModulesTH_Make MultiLayerModulesTH_OneShot T13701 ------------------------- The bytecode serialisation part was implemented by Cheng Shao Co-authored-by: Cheng Shao - - - - - dc8f9599 by Matthew Pickering at 2025-10-11T14:07:30-04:00 Revert "Add a perf test for #26425" This test has a large memory spike currently, which makes the test sensitive, since if you allocate a little more or less, the precise location where GC happens shifts and you observe a different part of the spike. Andreas told me to revert the patch for now, and he will add it back when he fixes the memory spike. This reverts commit 41bdb16fd083110a06507248f648c507a2feb4af. - - - - - e10dcd65 by Sven Tennie at 2025-10-12T10:24:56+00:00 T22859: Increase threadDelay for small machines The previously used thread delay led to failures on my RISC-V test setups. - - - - - d59ef6b6 by Hai / @BestYeen at 2025-10-14T21:51:14-04:00 Change Alex and Happy m4 scripts to display which version was found in the system, adapt small formatting details in Happy script to be more like the Alex script again. - - - - - c98abb6a by Hai / @BestYeen at 2025-10-14T21:52:08-04:00 Update occurrences of return to pure and add a sample for redefining :m to mean :main - - - - - 70ee825a by Cheng Shao at 2025-10-14T21:52:50-04:00 testsuite: fix T3586 for non-SSE3 platforms `T3586.hs` contains `-fvia-C -optc-msse3` which I think is a best-effort basis to harvest the C compiler's auto vectorization optimizations via the C backend back when the test was added. The `-fvia-C` part is now a deprecated no-op because GHC can't fall back to the C backend on a non-unregisterised build, and `-optc-msse3` might actually cause the test to fail on non x86/x64 platforms, e.g. recent builds of wasi-sdk would report `wasm32-wasi-clang: error: unsupported option '-msse3' for target 'wasm32-unknown-wasi'`. So this patch cleans up this historical cruft. `-fvia-C` is removed, and `-optc-msse3` is only passed when cpuid contains `pni` (which indicates support of SSE3). - - - - - 4be32153 by Teo Camarasu at 2025-10-15T08:06:09-04:00 Add submodules for template-haskell-lift and template-haskell-quasiquoter These two new boot libraries expose stable subsets of the template-haskell interface. This is an implemenation of the GHC proposal https://github.com/ghc-proposals/ghc-proposals/pull/696 Work towards #25262 - - - - - 0c00c9c3 by Ben Gamari at 2025-10-15T08:06:51-04:00 rts: Eliminate uses of implicit constant arrays Folding of `const`-sized variable-length arrays to a constant-length array is a gnu extension which clang complains about. Closes #26502. - - - - - bf902a1d by Fendor at 2025-10-15T16:00:59-04:00 Refactor distinct constructor tables map construction Adds `GHC.Types.Unique.FM.alterUFM_L`, `GHC.Types.Unique.DFM.alterUDFM_L` `GHC.Data.Word64Map.alterLookup` to support fusion of distinct constructor data insertion and lookup during the construction of the `DataCon` map in `GHC.Stg.Debug.numberDataCon`. Co-authored-by: Fendor Co-authored-by: Finley McIlwaine - - - - - b3585ba1 by Fendor at 2025-10-15T16:00:59-04:00 Allow per constructor refinement of distinct-constructor-tables Introduce `-fno-distinct-constructor-tables`. A distinct constructor table configuration is built from the combination of flags given, in order. For example, to only generate distinct constructor tables for a few specific constructors and no others, just pass `-fdistinct-constructor-tables-only=C1,...,CN`. This flag can be supplied multiple times to extend the set of constructors to generate a distinct info table for. You can disable generation of distinct constructor tables for all configurations by passing `-fno-distinct-constructor-tables`. The various configurations of these flags is included in the `DynFlags` fingerprints, which should result in the expected recompilation logic. Adds a test that checks for distinct tables for various given or omitted constructors. Updates CountDepsAst and CountDepsParser tests to account for new dependencies. Fixes #23703 Co-authored-by: Fendor Co-authored-by: Finley McIlwaine - - - - - e17dc695 by fendor at 2025-10-15T16:01:41-04:00 Fix typos in haddock documentation for stack annotation API - - - - - 3b314d20 by Zubin Duggal at 2025-10-16T18:06:43+05:30 compiler: Attempt to systematize Unique tags by introducing an ADT for each different tag Fixes #26264 The metric increase (max residency in T26425) has to do with GC timing Metric Decrease: T9233 Metric Increase: T26425 - - - - - 238 changed files: - .gitlab-ci.yml - .gitlab/generate-ci/gen_ci.hs - .gitlab/jobs.yaml - .gitmodules - compiler/GHC.hs - compiler/GHC/Builtin/PrimOps.hs - compiler/GHC/Builtin/Uniques.hs - compiler/GHC/ByteCode/Breakpoints.hs - + compiler/GHC/ByteCode/Serialize.hs - compiler/GHC/ByteCode/Types.hs - compiler/GHC/Cmm/Info.hs - compiler/GHC/Cmm/Info/Build.hs - compiler/GHC/Cmm/Pipeline.hs - compiler/GHC/Cmm/UniqueRenamer.hs - compiler/GHC/CmmToLlvm/Base.hs - compiler/GHC/Core/Multiplicity.hs - compiler/GHC/Core/Opt/Monad.hs - compiler/GHC/Core/Opt/Pipeline.hs - compiler/GHC/Core/Opt/Simplify/Monad.hs - compiler/GHC/Core/Predicate.hs - compiler/GHC/Core/TyCo/Compare.hs - compiler/GHC/Core/TyCo/Ppr.hs - compiler/GHC/Core/Type.hs - compiler/GHC/CoreToStg/Prep.hs - compiler/GHC/Data/FlatBag.hs - compiler/GHC/Data/SmallArray.hs - compiler/GHC/Data/Word64Map/Internal.hs - compiler/GHC/Data/Word64Map/Lazy.hs - compiler/GHC/Driver/Backend.hs - compiler/GHC/Driver/Backpack.hs - + compiler/GHC/Driver/ByteCode.hs - compiler/GHC/Driver/CodeOutput.hs - compiler/GHC/Driver/Config/Finder.hs - compiler/GHC/Driver/Config/Stg/Debug.hs - compiler/GHC/Driver/Downsweep.hs - compiler/GHC/Driver/DynFlags.hs - compiler/GHC/Driver/Env/Types.hs - compiler/GHC/Driver/Errors.hs - compiler/GHC/Driver/Flags.hs - compiler/GHC/Driver/Main.hs - compiler/GHC/Driver/Make.hs - compiler/GHC/Driver/MakeFile.hs - compiler/GHC/Driver/Messager.hs - compiler/GHC/Driver/Monad.hs - compiler/GHC/Driver/Pipeline/Execute.hs - compiler/GHC/Driver/Session.hs - compiler/GHC/Hs/Decls.hs - compiler/GHC/Hs/Type.hs - compiler/GHC/HsToCore/Breakpoints.hs - compiler/GHC/HsToCore/Foreign/JavaScript.hs - compiler/GHC/HsToCore/Monad.hs - compiler/GHC/HsToCore/Usage.hs - compiler/GHC/Iface/Binary.hs - compiler/GHC/Iface/Decl.hs - compiler/GHC/Iface/Ext/Ast.hs - compiler/GHC/Iface/Flags.hs - compiler/GHC/Iface/Load.hs - compiler/GHC/Iface/Make.hs - compiler/GHC/Iface/Recomp/Flags.hs - compiler/GHC/Iface/Rename.hs - compiler/GHC/Iface/Type.hs - compiler/GHC/JS/JStg/Monad.hs - compiler/GHC/Linker/Deps.hs - compiler/GHC/Linker/Loader.hs - compiler/GHC/Linker/Types.hs - compiler/GHC/Parser/Header.hs - compiler/GHC/Platform/Reg.hs - compiler/GHC/Runtime/Eval.hs - compiler/GHC/Stg/Debug.hs - + compiler/GHC/Stg/Debug/Types.hs - compiler/GHC/Stg/EnforceEpt.hs - compiler/GHC/Stg/Pipeline.hs - compiler/GHC/StgToCmm/ExtCode.hs - compiler/GHC/StgToCmm/Monad.hs - compiler/GHC/StgToJS/CodeGen.hs - compiler/GHC/StgToJS/Ids.hs - compiler/GHC/Tc/Errors.hs - compiler/GHC/Tc/Errors/Ppr.hs - compiler/GHC/Tc/Errors/Types.hs - compiler/GHC/Tc/Gen/HsType.hs - compiler/GHC/Tc/Gen/Splice.hs - compiler/GHC/Tc/Module.hs - compiler/GHC/Tc/Solver.hs - compiler/GHC/Tc/Solver/Equality.hs - compiler/GHC/Tc/Solver/Monad.hs - compiler/GHC/Tc/Solver/Solve.hs - compiler/GHC/Tc/TyCl.hs - compiler/GHC/Tc/Types.hs - compiler/GHC/Tc/Types/Constraint.hs - compiler/GHC/Tc/Types/CtLoc.hs - compiler/GHC/Tc/Types/Origin.hs - compiler/GHC/Tc/Utils/Monad.hs - compiler/GHC/Tc/Utils/TcMType.hs - compiler/GHC/Tc/Utils/TcType.hs - compiler/GHC/Tc/Utils/Unify.hs - compiler/GHC/Tc/Utils/Unify.hs-boot - compiler/GHC/Tc/Validity.hs - compiler/GHC/Types/Name/Cache.hs - compiler/GHC/Types/SourceError.hs - compiler/GHC/Types/SptEntry.hs - compiler/GHC/Types/Tickish.hs - compiler/GHC/Types/TyThing/Ppr.hs - compiler/GHC/Types/Unique.hs - compiler/GHC/Types/Unique/DFM.hs - compiler/GHC/Types/Unique/DSM.hs - compiler/GHC/Types/Unique/FM.hs - compiler/GHC/Types/Unique/Supply.hs - compiler/GHC/Unit/Finder.hs - compiler/GHC/Unit/Finder/Types.hs - compiler/GHC/Unit/Module/Graph.hs - compiler/GHC/Unit/Module/Location.hs - compiler/GHC/Unit/Module/ModSummary.hs - compiler/GHC/Unit/Module/WholeCoreBindings.hs - compiler/GHC/Utils/Binary.hs - compiler/GHC/Utils/Error.hs - compiler/GHC/Utils/Outputable.hs - compiler/ghc.cabal.in - docs/users_guide/debug-info.rst - docs/users_guide/ghci.rst - docs/users_guide/phases.rst - docs/users_guide/separate_compilation.rst - ghc/GHCi/UI.hs - hadrian/bindist/config.mk.in - hadrian/src/Packages.hs - hadrian/src/Settings/Default.hs - libraries/ghc-experimental/src/GHC/Stack/Annotation/Experimental.hs - libraries/ghc-internal/src/GHC/Internal/TH/Lift.hs - libraries/ghc-internal/src/GHC/Internal/TH/Quote.hs - + libraries/template-haskell-lift - + libraries/template-haskell-quasiquoter - m4/fptools_alex.m4 - m4/fptools_happy.m4 - rts/Printer.c - rts/include/rts/storage/Block.h - rts/posix/OSMem.c - rts/sm/NonMoving.c - rts/sm/NonMovingMark.c - rts/sm/Scav.c - testsuite/driver/cpu_features.py - testsuite/tests/bytecode/T24634/T24634a.stdout - 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