March 2026 - ghc-commits

[Git][ghc/ghc] Deleted branch wip/fix-head
by Cheng Shao (＠TerrorJack) 06 Mar '26

06 Mar '26

Cheng Shao deleted branch wip/fix-head at Glasgow Haskell Compiler / GHC -- You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][wip/marge_bot_batch_merge_job] 19 commits: Correct `hIsReadable` and `hIsWritable` for duplex handles
by Marge Bot (＠marge-bot) 06 Mar '26

06 Mar '26

Marge Bot pushed to branch wip/marge_bot_batch_merge_job at Glasgow Haskell Compiler / GHC Commits: 598db847 by Wolfgang Jeltsch at 2026-03-06T06:25:25-05:00 Correct `hIsReadable` and `hIsWritable` for duplex handles This contribution implements CLC proposal #371. It changes `hIsReadable` and `hIsWritable` such that they always throw a respective exception when encountering a closed or semi-closed handle, not just in the case of a file handle. - - - - - b90201e5 by Wolfgang Jeltsch at 2026-03-06T06:25:25-05:00 Document `SemiClosedHandle` - - - - - c9df72b5 by Wolfgang Jeltsch at 2026-03-06T06:25:25-05:00 Tell users what “semi-closed” means for duplex handles - - - - - a8aa1868 by Ilias Tsitsimpis at 2026-03-06T06:26:29-05:00 Fix determinism of linker arguments The switch from Data.Map to UniqMap in 3b5be05ac29 introduced non-determinism in the order of packages passed to the linker. This resulted in non-reproducible builds where the DT_NEEDED entries in dynamic libraries were ordered differently across builds. Fix the regression by explicitly sorting the package list derived from UniqMap. Fixes #26838 - - - - - 9b64ad3a by Matthew Pickering at 2026-03-06T06:27:16-05:00 determinism: Use a deterministic renaming when writing bytecode files Now when writing the bytecode file, a counter and substitution are used to provide deterministic keys to local variables (rather than relying on uniques). This change ensures that `.gbc` are produced deterministically. Fixes #26499 - - - - - d29800e0 by Teo Camarasu at 2026-03-06T06:28:46-05:00 ghc-internal: delete Version hs-boot loop Version has a Read instance which needs Unicode but part of the Unicode interface is the unicode version. This is easy to resolve. We simply don't re-export the version from the Unicode module. Resolves #26940 - - - - - ad25af90 by Sylvain Henry at 2026-03-06T06:30:33-05:00 Linker: implement support for COMMON symbols (#6107) Add some support for COMMON symbols. We don't support common symbols having different sizes where the larger one is allocated after the smaller one. The linker will fail with an appropriate error message if it happens. - - - - - 3b59f158 by Cheng Shao at 2026-03-06T06:31:16-05:00 compiler: fix redundant import of GHC.Hs.Lit This patch removes a redundant import of `GHC.Hs.Lit` which causes a ghc build failure with validate flavours when bootstrapping from 9.14. Fixes #26972. - - - - - 148d36f3 by Cheng Shao at 2026-03-06T06:32:01-05:00 compiler: avoid unneeded traversals in GHC.Unit.State Following !15591, this patch avoids unneeded traversals in `reportCycles`/`reportUnusable` when log verbosity is below given threshold. Also applies `logVerbAtLeast` when appropriate. Co-authored-by: Codex <codex(a)openai.com> - - - - - 7e31367c by Cheng Shao at 2026-03-06T06:32:46-05:00 ghc-internal: fix redundant import in GHC.Internal.Event.Windows.ManagedThreadPool This patch fixes redundant import in `GHC.Internal.Event.Windows.ManagedThreadPool` that causes a compilation error when building windows target with validate flavours and bootstrapping from 9.14. Fixes #26976. - - - - - fc8b8e27 by sheaf at 2026-03-06T06:33:28-05:00 System.Info.fullCompilerVersion: add 'since' annot Fixes #26973 - - - - - c8238375 by Sylvain Henry at 2026-03-06T06:34:23-05:00 Hadrian: deprecate --bignum and automatically enable +native_bignum for JS Deprecate --bignum=... to select the bignum backend. It's only used to select the native backend, and this can be done with the +native_bignum flavour transformer. Additionally, we automatically enable +native_bignum for the JS target because the GMP backend isn't supported. - - - - - a3ac7074 by Sylvain Henry at 2026-03-06T06:35:17-05:00 JS: fix putEnum/fromEnum (#24593) Don't go through Word16 when serializing Enums. - - - - - 0b36e96c by Andreas Klebinger at 2026-03-06T06:35:58-05:00 Docs: Document -fworker-wrapper-cbv default setting. Fixes #26841 - - - - - 6b4342eb by mangoiv at 2026-03-06T07:09:26-05:00 drop deb9/10 from CI, add deb13 debian 9 and 10 are end of life, hence we drop them from our CI, but we do add debian 13. Jobs that were previously run on 9 and 10 run on 13, too, jobs that were run on 10, are run on 11 now. Jobs that were previously run on debian 12 are run on debian 13 now. This MR also updates hadrian's bootstrap plans for that reason. Metric Decrease: T9872d - - - - - 73ef9d67 by Luite Stegeman at 2026-03-06T07:09:41-05:00 Fix GHC.Internal.Prim haddock Haddock used to parse Haskell source to generate documentation, but switched to using interface files instead. This broke documentation of the GHC.Internal.Prim module, since it's a wired-in interface that didn't provide a document structure. This patch adds the missing document structure and updates genprimopcode to make the section headers and descriptions available. fixes #26954 - - - - - d91c8909 by Luite Stegeman at 2026-03-06T07:09:41-05:00 Remove obsolete --make-haskell-source from genprimopcode Now that haddock uses the wired-in interface for GHC.Internal.Prim, the generated Haskell source file is no longer needed. Remove the --make-haskell-source code generator from genprimopcode and replace the generated GHC/Internal/Prim.hs with a minimal static source file. - - - - - a463265e by Sylvain Henry at 2026-03-06T07:09:47-05:00 JS: fix linking of exposed but non-preload units (#24886) Units exposed in the unit database but not explicitly passed on the command-line were not considered by the JS linker. This isn't an issue for cabal which passes every unit explicitly but it is an issue when using GHC directly (cf T24886 test). - - - - - a8f0a2d2 by mangoiv at 2026-03-06T07:09:53-05:00 testsuite: double foundation timeout multiplier The runtime timeout in the foundation test was regularly hit by code generated by the wasm backend - we increase the timout since the high runtime is expected on the wasm backend for this rather complex test. Resolves #26938 - - - - - 70 changed files: - .gitlab-ci.yml - .gitlab/generate-ci/gen_ci.hs - .gitlab/jobs.yaml - .gitlab/rel_eng/fetch-gitlab-artifacts/fetch_gitlab.py - .gitlab/rel_eng/mk-ghcup-metadata/mk_ghcup_metadata.py - compiler/GHC/Builtin/PrimOps.hs - compiler/GHC/Builtin/Utils.hs - compiler/GHC/Builtin/primops.txt.pp - compiler/GHC/ByteCode/Serialize.hs - compiler/GHC/Driver/Main.hs - compiler/GHC/Hs/Type.hs - compiler/GHC/Runtime/Interpreter/JS.hs - compiler/GHC/StgToJS/Object.hs - compiler/GHC/Unit/State.hs - compiler/GHC/Utils/Error.hs - docs/users_guide/using-optimisation.rst - hadrian/README.md - hadrian/bootstrap/generate_bootstrap_plans - hadrian/bootstrap/plan-9_10_1.json - hadrian/bootstrap/plan-9_10_2.json - + hadrian/bootstrap/plan-9_10_3.json - hadrian/bootstrap/plan-bootstrap-9_10_1.json - hadrian/bootstrap/plan-bootstrap-9_10_2.json - + hadrian/bootstrap/plan-bootstrap-9_10_3.json - hadrian/src/CommandLine.hs - hadrian/src/Main.hs - hadrian/src/Rules/Generate.hs - hadrian/src/Settings.hs - hadrian/src/Settings/Builders/GenPrimopCode.hs - libraries/base/changelog.md - libraries/base/src/GHC/Unicode.hs - libraries/base/src/System/Info.hs - libraries/ghc-internal/ghc-internal.cabal.in - − libraries/ghc-internal/src/GHC/Internal/Data/Version.hs-boot - libraries/ghc-internal/src/GHC/Internal/Event/Windows/ManagedThreadPool.hs - libraries/ghc-internal/src/GHC/Internal/IO/Handle.hs - libraries/ghc-internal/src/GHC/Internal/IO/Handle/Text.hs - libraries/ghc-internal/src/GHC/Internal/IO/Handle/Types.hs - + libraries/ghc-internal/src/GHC/Internal/Prim.hs - libraries/ghc-internal/src/GHC/Internal/Unicode.hs - libraries/ghc-internal/src/GHC/Internal/Unicode/Version.hs - libraries/ghc-internal/tools/ucd2haskell/exe/UCD2Haskell/ModuleGenerators.hs - rts/Linker.c - rts/LinkerInternals.h - rts/linker/Elf.c - rts/linker/MachO.c - rts/linker/PEi386.c - testsuite/driver/perf_notes.py - testsuite/tests/ghci/should_run/all.T - + testsuite/tests/javascript/T24886.hs - + testsuite/tests/javascript/T24886.stderr - + testsuite/tests/javascript/T24886.stdout - testsuite/tests/javascript/all.T - testsuite/tests/numeric/should_run/all.T - testsuite/tests/overloadedrecflds/should_compile/all.T - testsuite/tests/overloadedrecflds/should_run/all.T - testsuite/tests/pmcheck/should_compile/T11303.hs - testsuite/tests/quasiquotation/qq005/test.T - testsuite/tests/quasiquotation/qq006/test.T - testsuite/tests/rts/linker/Makefile - + testsuite/tests/rts/linker/T6107.hs - + testsuite/tests/rts/linker/T6107.stdout - + testsuite/tests/rts/linker/T6107_sym1.s - + testsuite/tests/rts/linker/T6107_sym2.s - testsuite/tests/rts/linker/all.T - testsuite/tests/saks/should_compile/all.T - testsuite/tests/showIface/all.T - testsuite/tests/th/all.T - testsuite/tests/vdq-rta/should_compile/all.T - utils/genprimopcode/Main.hs The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/4281bc8b7b124f8553e2865f027882… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/4281bc8b7b124f8553e2865f027882… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][master] Docs: Document -fworker-wrapper-cbv default setting.
by Marge Bot (＠marge-bot) 06 Mar '26

06 Mar '26

Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC Commits: 0b36e96c by Andreas Klebinger at 2026-03-06T06:35:58-05:00 Docs: Document -fworker-wrapper-cbv default setting. Fixes #26841 - - - - - 1 changed file: - docs/users_guide/using-optimisation.rst Changes: ===================================== docs/users_guide/using-optimisation.rst ===================================== @@ -1925,6 +1925,8 @@ as such you shouldn't need to set any of them explicitly. A flag :type: dynamic :category: optimization + :default: off + Disabling this flag prevents a W/W split if the only benefit would be call-by-value for some arguments. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/0b36e96cb93db71f201aaa055c4a90b… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/0b36e96cb93db71f201aaa055c4a90b… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][master] JS: fix putEnum/fromEnum (#24593)
by Marge Bot (＠marge-bot) 06 Mar '26

06 Mar '26

Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC Commits: a3ac7074 by Sylvain Henry at 2026-03-06T06:35:17-05:00 JS: fix putEnum/fromEnum (#24593) Don't go through Word16 when serializing Enums. - - - - - 1 changed file: - compiler/GHC/StgToJS/Object.hs Changes: ===================================== compiler/GHC/StgToJS/Object.hs ===================================== @@ -406,12 +406,10 @@ readObjectBlocks file bids = do -------------------------------------------------------------------------------- putEnum :: Enum a => WriteBinHandle -> a -> IO () -putEnum bh x | n > 65535 = error ("putEnum: out of range: " ++ show n) - | otherwise = put_ bh n - where n = fromIntegral $ fromEnum x :: Word16 +putEnum bh x = put_ bh (fromEnum x) getEnum :: Enum a => ReadBinHandle -> IO a -getEnum bh = toEnum . fromIntegral <$> (get bh :: IO Word16) +getEnum bh = toEnum <$> (get bh) -- | Helper to convert Int to Int32 toI32 :: Int -> Int32 View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/a3ac7074987fb8d72119b1d2ba4df91… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/a3ac7074987fb8d72119b1d2ba4df91… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][master] Hadrian: deprecate --bignum and automatically enable +native_bignum for JS
by Marge Bot (＠marge-bot) 06 Mar '26

06 Mar '26

Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC Commits: c8238375 by Sylvain Henry at 2026-03-06T06:34:23-05:00 Hadrian: deprecate --bignum and automatically enable +native_bignum for JS Deprecate --bignum=... to select the bignum backend. It's only used to select the native backend, and this can be done with the +native_bignum flavour transformer. Additionally, we automatically enable +native_bignum for the JS target because the GMP backend isn't supported. - - - - - 4 changed files: - hadrian/README.md - hadrian/src/CommandLine.hs - hadrian/src/Main.hs - hadrian/src/Settings.hs Changes: ===================================== hadrian/README.md ===================================== @@ -101,7 +101,9 @@ Stage2 GHC. * `--skip-depends`: skips rebuilding Haskell module dependency files. -* `--bignum={native,gmp,check-gmp,ffi}`: choose which bignum implementation to use. The default is `gmp`. +* `--bignum={native,gmp,check-gmp,ffi}`: **Deprecated.** Use the `+native_bignum` flavour + transformer instead (e.g. `--flavour=default+native_bignum`). When building for the + JavaScript target, the native bignum backend is enabled automatically. * `--color` and `--no-color`: choose whether to use colors when printing build progress info. By default, Hadrian tries to determine if the terminal supports ===================================== hadrian/src/CommandLine.hs ===================================== @@ -1,5 +1,6 @@ module CommandLine ( optDescrs, cmdLineArgsMap, cmdFlavour, lookupFreeze1, lookupFreeze2, lookupSkipDepends, + lookupBignum, cmdBignum, cmdBignumCheck, cmdProgressInfo, cmdCompleteSetting, cmdDocsArgs, cmdUnitIdHash, lookupBuildRoot, TestArgs(..), TestSpeed(..), defaultTestArgs, cmdPrefix, DocArgs(..), defaultDocArgs @@ -389,6 +390,9 @@ lookupFreeze2 = freeze2 . lookupExtra defaultCommandLineArgs lookupSkipDepends :: Map.HashMap TypeRep Dynamic -> Bool lookupSkipDepends = skipDepends . lookupExtra defaultCommandLineArgs +lookupBignum :: Map.HashMap TypeRep Dynamic -> Maybe String +lookupBignum = bignum . lookupExtra defaultCommandLineArgs + cmdUnitIdHash :: Action Bool cmdUnitIdHash = unitIdHash <$> cmdLineArgs ===================================== hadrian/src/Main.hs ===================================== @@ -34,6 +34,13 @@ main = do -- Provide access to command line arguments and some user settings through -- Shake's type-indexed map 'shakeExtra'. argsMap <- CommandLine.cmdLineArgsMap + case CommandLine.lookupBignum argsMap of + Just _ -> hPutStrLn stderr $ unlines + [ "Warning: --bignum is deprecated." + , " Use the '+native_bignum' flavour transformer instead (e.g. --flavour=default+native_bignum)." + , " When building for the JavaScript target, native bignum is now enabled automatically." + ] + Nothing -> return () let extra = insertExtra UserSettings.buildProgressColour $ insertExtra UserSettings.successColour $ argsMap ===================================== hadrian/src/Settings.hs ===================================== @@ -30,6 +30,7 @@ import Settings.Flavours.Release import Hadrian.Oracles.TextFile import GHC.Toolchain.Target import GHC.Platform.ArchOS +import Oracles.Setting (isJsTarget) getExtraArgs :: Args getExtraArgs = expr flavour >>= extraArgs @@ -44,9 +45,7 @@ getRtsWays :: Ways getRtsWays = expr flavour >>= rtsWays getBignumBackend :: Expr String -getBignumBackend = expr $ cmdBignum >>= \case - Nothing -> bignumBackend <$> flavour - Just b -> pure b +getBignumBackend = bignumBackend <$> expr flavour getBignumCheck :: Expr Bool getBignumCheck = expr $ cmdBignum >>= \case @@ -90,9 +89,17 @@ flavour = do $ "failed to apply key-value settings:\n\t" ++ unlines (map (" - " ++) settingErrs) ++ "\t Entries should look something like \"stage1.containers.ghc.hs.opts += -Werror\"" + -- Handle --bignum (deprecated) and JS auto-detection + bignumTweak <- cmdBignum >>= \case + Just "native" -> return useNativeBignum + Just b -> return $ \f -> f { bignumBackend = b } + Nothing -> do + js <- isJsTarget + return $ if js then useNativeBignum else id + case parseFlavour flavours flavourTransformers flavourName of Left err -> fail err - Right f -> return $ flagsTweak (tweak f) + Right f -> return $ bignumTweak (flagsTweak (tweak f)) -- TODO: switch to Set Package as the order of packages should not matter? -- Otherwise we have to keep remembering to sort packages from time to time. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/c8238375562a6c003b62dcccd452ed3… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/c8238375562a6c003b62dcccd452ed3… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][master] System.Info.fullCompilerVersion: add 'since' annot
by Marge Bot (＠marge-bot) 06 Mar '26

06 Mar '26

Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC Commits: fc8b8e27 by sheaf at 2026-03-06T06:33:28-05:00 System.Info.fullCompilerVersion: add 'since' annot Fixes #26973 - - - - - 1 changed file: - libraries/base/src/System/Info.hs Changes: ===================================== libraries/base/src/System/Info.hs ===================================== @@ -42,6 +42,8 @@ compilerVersion = Version [major, minor] [] -- | The full version of 'compilerName' with which the program was compiled -- or is being interpreted. It includes the major, minor, revision and an additional -- identifier, generally in the form "<year><month><day>". +-- +-- @since 4.15.0.0 fullCompilerVersion :: Version fullCompilerVersion = Version version [] where View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/fc8b8e27398b4d9d901fb65d15a7d8b… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/fc8b8e27398b4d9d901fb65d15a7d8b… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][master] ghc-internal: fix redundant import in GHC.Internal.Event.Windows.ManagedThreadPool
by Marge Bot (＠marge-bot) 06 Mar '26

06 Mar '26

Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC Commits: 7e31367c by Cheng Shao at 2026-03-06T06:32:46-05:00 ghc-internal: fix redundant import in GHC.Internal.Event.Windows.ManagedThreadPool This patch fixes redundant import in `GHC.Internal.Event.Windows.ManagedThreadPool` that causes a compilation error when building windows target with validate flavours and bootstrapping from 9.14. Fixes #26976. - - - - - 1 changed file: - libraries/ghc-internal/src/GHC/Internal/Event/Windows/ManagedThreadPool.hs Changes: ===================================== libraries/ghc-internal/src/GHC/Internal/Event/Windows/ManagedThreadPool.hs ===================================== @@ -31,7 +31,6 @@ import GHC.Internal.Control.Concurrent.MVar import GHC.Internal.Data.Maybe import GHC.Internal.Base import GHC.Internal.Num ((-), (+)) -import GHC.Internal.Real (fromIntegral) import qualified GHC.Internal.Event.Array as A import GHC.Internal.IO.Handle.Internals (debugIO) import GHC.Internal.Conc.Sync (ThreadId(..)) View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/7e31367c832225f2d7b277077444c2a… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/7e31367c832225f2d7b277077444c2a… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][master] compiler: avoid unneeded traversals in GHC.Unit.State
by Marge Bot (＠marge-bot) 06 Mar '26

06 Mar '26

Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC Commits: 148d36f3 by Cheng Shao at 2026-03-06T06:32:01-05:00 compiler: avoid unneeded traversals in GHC.Unit.State Following !15591, this patch avoids unneeded traversals in `reportCycles`/`reportUnusable` when log verbosity is below given threshold. Also applies `logVerbAtLeast` when appropriate. Co-authored-by: Codex <codex(a)openai.com> - - - - - 2 changed files: - compiler/GHC/Unit/State.hs - compiler/GHC/Utils/Error.hs Changes: ===================================== compiler/GHC/Unit/State.hs ===================================== @@ -1279,7 +1279,7 @@ pprReason pref reason = case reason of nest 2 (hsep (map ppr deps)) reportCycles :: Logger -> [SCC UnitInfo] -> IO () -reportCycles logger sccs = mapM_ report sccs +reportCycles logger sccs = when (logVerbAtLeast logger 2) $ mapM_ report sccs where report (AcyclicSCC _) = return () report (CyclicSCC vs) = @@ -1288,7 +1288,7 @@ reportCycles logger sccs = mapM_ report sccs nest 2 (hsep (map (ppr . unitId) vs)) reportUnusable :: Logger -> UnusableUnits -> IO () -reportUnusable logger pkgs = mapM_ report (nonDetUniqMapToList pkgs) +reportUnusable logger pkgs = when (logVerbAtLeast logger 2) $ mapM_ report (nonDetUniqMapToList pkgs) where report (ipid, (_, reason)) = debugTraceMsg logger 2 $ @@ -1389,7 +1389,7 @@ mergeDatabases logger = foldM merge (emptyUniqMap, emptyUniqMap) . zip [1..] merge (pkg_map, prec_map) (i, UnitDatabase db_path db) = do debugTraceMsg logger 2 $ text "loading package database" <+> ppr db_path - when (log_verbosity (logFlags logger) >= 2) $ + when (logVerbAtLeast logger 2) $ forM_ (Set.toList override_set) $ \pkg -> debugTraceMsg logger 2 $ text "package" <+> ppr pkg <+> ===================================== compiler/GHC/Utils/Error.hs ===================================== @@ -463,7 +463,7 @@ withTiming' logger what force_result prtimings action debugTraceMsg :: Logger -> Int -> SDoc -> IO () debugTraceMsg logger val msg = - when (log_verbosity (logFlags logger) >= val) $ + when (logVerbAtLeast logger val) $ logInfo logger (withPprStyle defaultDumpStyle msg) {-# INLINE debugTraceMsg #-} -- see Note [INLINE conditional tracing utilities] View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/148d36f36711a58fbb7e6b569786916… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/148d36f36711a58fbb7e6b569786916… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][master] compiler: fix redundant import of GHC.Hs.Lit
by Marge Bot (＠marge-bot) 06 Mar '26

06 Mar '26

Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC Commits: 3b59f158 by Cheng Shao at 2026-03-06T06:31:16-05:00 compiler: fix redundant import of GHC.Hs.Lit This patch removes a redundant import of `GHC.Hs.Lit` which causes a ghc build failure with validate flavours when bootstrapping from 9.14. Fixes #26972. - - - - - 1 changed file: - compiler/GHC/Hs/Type.hs Changes: ===================================== compiler/GHC/Hs/Type.hs ===================================== @@ -117,7 +117,6 @@ import GHC.Core.Ppr ( pprOccWithTick) import GHC.Core.Type import GHC.Core.Multiplicity( pprArrowWithMultiplicity ) import GHC.Hs.Doc -import GHC.Hs.Lit (pprHsStringLit) import GHC.Generics (Generic, Generically(..)) import GHC.Types.Basic import GHC.Types.SrcLoc View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/3b59f15865652edbe873a380f73be46… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/3b59f15865652edbe873a380f73be46… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][master] Linker: implement support for COMMON symbols (#6107)
by Marge Bot (＠marge-bot) 06 Mar '26

06 Mar '26

Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC Commits: ad25af90 by Sylvain Henry at 2026-03-06T06:30:33-05:00 Linker: implement support for COMMON symbols (#6107) Add some support for COMMON symbols. We don't support common symbols having different sizes where the larger one is allocated after the smaller one. The linker will fail with an appropriate error message if it happens. - - - - - 11 changed files: - rts/Linker.c - rts/LinkerInternals.h - rts/linker/Elf.c - rts/linker/MachO.c - rts/linker/PEi386.c - testsuite/tests/rts/linker/Makefile - + testsuite/tests/rts/linker/T6107.hs - + testsuite/tests/rts/linker/T6107.stdout - + testsuite/tests/rts/linker/T6107_sym1.s - + testsuite/tests/rts/linker/T6107_sym2.s - testsuite/tests/rts/linker/all.T Changes: ===================================== rts/Linker.c ===================================== @@ -268,6 +268,7 @@ int ghciInsertSymbolTable( SymbolAddr* data, SymStrength strength, SymType type, + unsigned long size, ObjectCode *owner) { RtsSymbolInfo *pinfo = lookupStrHashTable(table, key); @@ -278,6 +279,7 @@ int ghciInsertSymbolTable( pinfo->owner = owner; pinfo->strength = strength; pinfo->type = type; + pinfo->size = size; insertStrHashTable(table, key, pinfo); return 1; } @@ -290,6 +292,7 @@ int ghciInsertSymbolTable( pinfo->owner = owner; pinfo->strength = strength; pinfo->type = type; + pinfo->size = size; return 1; } /* We were asked to discard the symbol on duplicates, do so quietly. */ @@ -318,6 +321,7 @@ int ghciInsertSymbolTable( /* The existing symbol is weak with a zero value; replace it with the new symbol. */ pinfo->value = data; pinfo->owner = owner; + pinfo->size = size; return 1; } else if (strength == STRENGTH_WEAK) @@ -336,6 +340,7 @@ int ghciInsertSymbolTable( pinfo->value = data; pinfo->owner = owner; pinfo->strength = strength; + pinfo->size = size; return 1; } else if ( pinfo->owner @@ -360,6 +365,7 @@ int ghciInsertSymbolTable( pinfo->value = data; pinfo->owner = owner; pinfo->strength = strength; + pinfo->size = size; } return 1; @@ -477,7 +483,7 @@ initLinker_ (int retain_cafs) IF_DEBUG(linker, debugBelch("initLinker: inserting rts symbol %s, %p\n", sym->lbl, sym->addr)); if (! ghciInsertSymbolTable(WSTR("(GHCi built-in symbols)"), symhash, sym->lbl, sym->addr, - sym->strength, sym->type, NULL)) { + sym->strength, sym->type, 0, NULL)) { barf("ghciInsertSymbolTable failed"); } } @@ -495,7 +501,7 @@ initLinker_ (int retain_cafs) IF_DEBUG(linker, debugBelch("initLinker: inserting extra rts symbol %s, %p\n", sym->lbl, sym->addr)); if (! ghciInsertSymbolTable(WSTR("(GHCi built-in symbols)"), symhash, sym->lbl, sym->addr, - sym->strength, sym->type, NULL)) { + sym->strength, sym->type, 0, NULL)) { barf("ghciInsertSymbolTable failed"); } } @@ -506,7 +512,7 @@ initLinker_ (int retain_cafs) if (! ghciInsertSymbolTable(WSTR("(GHCi built-in symbols)"), symhash, MAYBE_LEADING_UNDERSCORE_STR("newCAF"), retain_cafs ? newRetainedCAF : newGCdCAF, - HS_BOOL_FALSE, SYM_TYPE_CODE, NULL)) { + HS_BOOL_FALSE, SYM_TYPE_CODE, 0, NULL)) { barf("ghciInsertSymbolTable failed"); } @@ -778,7 +784,7 @@ HsBool removeLibrarySearchPath(HsPtr dll_path_index) HsInt insertSymbol(pathchar* obj_name, SymbolName* key, SymbolAddr* data) { return ghciInsertSymbolTable(obj_name, symhash, key, data, HS_BOOL_FALSE, - SYM_TYPE_CODE, NULL); + SYM_TYPE_CODE, 0, NULL); } /* ----------------------------------------------------------------------------- @@ -1623,7 +1629,7 @@ int ocTryLoad (ObjectCode* oc) { && !ghciInsertSymbolTable(oc->fileName, symhash, symbol.name, symbol.addr, isSymbolWeak(oc, symbol.name), - symbol.type, oc)) { + symbol.type, 0, oc)) { return 0; } } ===================================== rts/LinkerInternals.h ===================================== @@ -418,6 +418,7 @@ typedef struct _RtsSymbolInfo { ObjectCode *owner; SymStrength strength; SymType type; + unsigned long size; // symbol size: only used for COMMON symbols } RtsSymbolInfo; #include "BeginPrivate.h" @@ -441,6 +442,7 @@ int ghciInsertSymbolTable( SymbolAddr* data, SymStrength weak, SymType type, + unsigned long size, ObjectCode *owner); /* Lock-free version of lookupSymbol. When 'dependent' is not NULL, adds it as a ===================================== rts/linker/Elf.c ===================================== @@ -961,7 +961,11 @@ ocGetNames_ELF ( ObjectCode* oc ) for (size_t j = 0; j < symTab->n_symbols; j++) { ElfSymbol *symbol = &symTab->symbols[j]; if (SHN_COMMON == symTab->symbols[j].elf_sym->st_shndx) { - common_size += symbol->elf_sym->st_size; + /* Skip COMMON symbols already defined by a previously-loaded + * object; we will reuse the existing allocation. */ + if (!lookupStrHashTable(symhash, symTab->symbols[j].name)) { + common_size += symbol->elf_sym->st_size; + } } } } @@ -1006,17 +1010,35 @@ ocGetNames_ELF ( ObjectCode* oc ) /* Figure out if we want to add it; if so, set ad to its address. Otherwise leave ad == NULL. */ + bool common_already_defined = false; if (shndx == SHN_COMMON) { isLocal = false; - CHECK(common_used < common_size); - CHECK(common_mem); - symbol->addr = (void*)((uintptr_t)common_mem + common_used); - common_used += symbol->elf_sym->st_size; - CHECK(common_used <= common_size); - - IF_DEBUG(linker_verbose, - debugBelch("COMMON symbol, size %llu name %s allocated at %p\n", - (long long unsigned int) symbol->elf_sym->st_size, nm, symbol->addr)); + RtsSymbolInfo *existing = lookupStrHashTable(symhash, nm); + if (existing != NULL) { + /* COMMON symbol already allocated by a previously-loaded + * object; reuse that address so relocations resolve to + * the same storage. */ + if(symbol->elf_sym->st_size > existing->size) { + barf("linker: trying to link COMMON symbols %s with incompatible sizes: previous size %llu, new size %llu\n", + nm, + (long long unsigned int) existing->size, + (long long unsigned int) symbol->elf_sym->st_size); + } + symbol->addr = existing->value; + common_already_defined = true; + IF_DEBUG(linker_verbose, + debugBelch("COMMON symbol, size %llu name %s reusing address %p\n", + (long long unsigned int) symbol->elf_sym->st_size, nm, symbol->addr)); + } else { + CHECK(common_used < common_size); + CHECK(common_mem); + symbol->addr = (void*)((uintptr_t)common_mem + common_used); + common_used += symbol->elf_sym->st_size; + CHECK(common_used <= common_size); + IF_DEBUG(linker_verbose, + debugBelch("COMMON symbol, size %llu name %s allocated at %p\n", + (long long unsigned int) symbol->elf_sym->st_size, nm, symbol->addr)); + } /* Pointless to do addProddableBlock() for this area, since the linker should never poke around in it. */ @@ -1080,13 +1102,13 @@ ocGetNames_ELF ( ObjectCode* oc ) if (symbol->addr != NULL) { CHECK(nm != NULL); /* Acquire! */ - if (!isLocal) { + if (!isLocal && !common_already_defined) { if (isWeak == HS_BOOL_TRUE) { setWeakSymbol(oc, nm); } if (!ghciInsertSymbolTable(oc->fileName, symhash, - nm, symbol->addr, isWeak, sym_type, oc) + nm, symbol->addr, isWeak, sym_type, symbol->elf_sym->st_size, oc) ) { goto fail; } ===================================== rts/linker/MachO.c ===================================== @@ -1421,8 +1421,13 @@ ocGetNames_MachO(ObjectCode* oc) if((oc->info->nlist[i].n_type & N_TYPE) == N_UNDF && (oc->info->nlist[i].n_value != 0)) { - commonSize += oc->info->nlist[i].n_value; oc->n_symbols++; + /* Only allocate space for COMMON symbols not already + * defined by a previously-loaded object. */ + SymbolName *nm_c = oc->info->macho_symbols[i].name; + if (!lookupStrHashTable(symhash, nm_c)) { + commonSize += oc->info->nlist[i].n_value; + } } else if((oc->info->nlist[i].n_type & N_TYPE) == N_SECT) oc->n_symbols++; @@ -1436,7 +1441,7 @@ ocGetNames_MachO(ObjectCode* oc) */ IF_DEBUG(linker, debugBelch("ocGetNames_MachO: %d external symbols\n", oc->n_symbols)); - oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(Symbol_t), + oc->symbols = stgCallocBytes(oc->n_symbols, sizeof(Symbol_t), "ocGetNames_MachO(oc->symbols)"); if (oc->info->symCmd) { @@ -1467,6 +1472,7 @@ ocGetNames_MachO(ObjectCode* oc) , addr , HS_BOOL_FALSE , sym_type + , 0 , oc); oc->symbols[curSymbol].name = nm; @@ -1488,8 +1494,10 @@ ocGetNames_MachO(ObjectCode* oc) } /* setup the common storage */ - commonStorage = stgCallocBytes(1,commonSize,"ocGetNames_MachO(common symbols)"); - commonCounter = (unsigned long)commonStorage; + if (commonSize > 0) { + commonStorage = stgCallocBytes(1, commonSize, "ocGetNames_MachO(common symbols)"); + commonCounter = (unsigned long)commonStorage; + } if (oc->info->symCmd) { for (size_t i = 0; i < oc->info->n_macho_symbols; i++) { @@ -1499,22 +1507,47 @@ ocGetNames_MachO(ObjectCode* oc) && (nlist->n_type & N_EXT) && (nlist->n_value != 0)) { unsigned long sz = nlist->n_value; - - nlist->n_value = commonCounter; - - /* also set the final address to the macho_symbol */ - oc->info->macho_symbols[i].addr = (void*)commonCounter; /* TODO: Figure out how to determine this from object */ SymType sym_type = SYM_TYPE_CODE; - IF_DEBUG(linker_verbose, debugBelch("ocGetNames_MachO: inserting common symbol: %s\n", nm)); - ghciInsertSymbolTable(oc->fileName, symhash, nm, - (void*)commonCounter, HS_BOOL_FALSE, sym_type, oc); - oc->symbols[curSymbol].name = nm; - oc->symbols[curSymbol].addr = oc->info->macho_symbols[i].addr; - curSymbol++; + RtsSymbolInfo *existing = lookupStrHashTable(symhash, nm); + if (existing != NULL) { + /* COMMON symbol already allocated by a previously-loaded + * object; reuse that address so relocations resolve to + * the same storage. */ + if (sz > existing->size) { + barf("linker: trying to link COMMON symbols %s with" + " incompatible sizes: previous size %llu," + " new size %lu\n", + nm, + (long long unsigned int) existing->size, + sz); + } + nlist->n_value = (unsigned long)existing->value; + oc->info->macho_symbols[i].addr = existing->value; + IF_DEBUG(linker_verbose, + debugBelch("ocGetNames_MachO: COMMON symbol %s" + " reusing address %p\n", + nm, existing->value)); + /* Don't add to oc->symbols: not the owner */ + } else { + nlist->n_value = commonCounter; + /* also set the final address to the macho_symbol */ + oc->info->macho_symbols[i].addr = (void*)commonCounter; - commonCounter += sz; + IF_DEBUG(linker_verbose, + debugBelch("ocGetNames_MachO: inserting common symbol: %s\n", nm)); + ghciInsertSymbolTable(oc->fileName, symhash, nm, + (void*)commonCounter, HS_BOOL_FALSE, + sym_type, + sz, oc); + oc->symbols[curSymbol].name = nm; + oc->symbols[curSymbol].addr = oc->info->macho_symbols[i].addr; + oc->symbols[curSymbol].type = sym_type; + curSymbol++; + + commonCounter += sz; + } } } } ===================================== rts/linker/PEi386.c ===================================== @@ -573,7 +573,7 @@ void initLinker_PEi386(void) if (!ghciInsertSymbolTable(WSTR("(GHCi/Ld special symbols)"), symhash, "__image_base__", GetModuleHandleW (NULL), HS_BOOL_TRUE, - SYM_TYPE_CODE, NULL)) { + SYM_TYPE_CODE, 0, NULL)) { barf("ghciInsertSymbolTable failed"); } @@ -1186,7 +1186,7 @@ bool checkAndLoadImportLibrary( pathchar* arch_name, char* member_name, FILE* f SymType symType = SYM_TYPE_DUP_DISCARD | SYM_TYPE_HIDDEN; symType |= hdr.Type == IMPORT_OBJECT_CODE ? SYM_TYPE_CODE : SYM_TYPE_DATA; - if (!ghciInsertSymbolTable(dll, symhash, symbol, sym, false, symType, NULL)) + if (!ghciInsertSymbolTable(dll, symhash, symbol, sym, false, symType, 0, NULL)) return false; return true; @@ -1825,7 +1825,12 @@ ocGetNames_PEi386 ( ObjectCode* oc ) if (getSymSectionNumber (info, sym) == PE_SECTION_UNDEFINED && getSymValue (info, sym) > 0 && getSymStorageClass (info, sym) != IMAGE_SYM_CLASS_SECTION) { - globalBssSize += getSymValue (info, sym); + /* Only count COMMON symbols not already defined by a + * previously-loaded object; we will reuse their allocation. */ + SymbolName *nm = get_sym_name (getSymShortName (info, sym), oc); + if (!lookupStrHashTable(symhash, nm)) { + globalBssSize += getSymValue (info, sym); + } } i += getSymNumberOfAuxSymbols (info, sym); } @@ -1859,6 +1864,8 @@ ocGetNames_PEi386 ( ObjectCode* oc ) uint8_t symStorageClass = getSymStorageClass (info, sym); SymbolAddr *addr = NULL; bool isWeak = false; + bool common_already_defined = false; + unsigned long symSize = 0; SymbolName *sname = get_sym_name (getSymShortName (info, sym), oc); uint32_t secNumber = getSymSectionNumber (info, sym); @@ -1959,10 +1966,31 @@ ocGetNames_PEi386 ( ObjectCode* oc ) } else if ( secNumber == IMAGE_SYM_UNDEFINED && symValue > 0) { /* This symbol isn't in any section at all, ie, global bss. - Allocate zeroed space for it from the BSS section */ - addr = bss; - bss = (SymbolAddr*)((StgWord)bss + (StgWord)symValue); - IF_DEBUG(linker_verbose, debugBelch("bss symbol @ %p %u\n", addr, symValue)); + Allocate zeroed space for it from the BSS section, unless a + previously-loaded object already allocated storage for it. */ + RtsSymbolInfo *existing = lookupStrHashTable(symhash, sname); + if (existing != NULL) { + /* COMMON symbol already allocated by a previously-loaded + * object; reuse that address so relocations resolve to + * the same storage. */ + if (symValue > existing->size) { + barf("linker: trying to link COMMON symbols %s with" + " incompatible sizes: previous size %llu," + " new size %u\n", + sname, + (long long unsigned int) existing->size, + symValue); + } + addr = existing->value; + common_already_defined = true; + IF_DEBUG(linker_verbose, + debugBelch("bss symbol reusing @ %p %u\n", addr, symValue)); + } else { + addr = bss; + bss = (SymbolAddr*)((StgWord)bss + (StgWord)symValue); + symSize = (unsigned long)symValue; + IF_DEBUG(linker_verbose, debugBelch("bss symbol @ %p %u\n", addr, symValue)); + } } else if (section && section->kind == SECTIONKIND_BFD_IMPORT_LIBRARY) { /* Disassembly of section .idata$5: @@ -1990,7 +2018,7 @@ ocGetNames_PEi386 ( ObjectCode* oc ) type = has_code_section ? SYM_TYPE_CODE : SYM_TYPE_DATA; type |= SYM_TYPE_DUP_DISCARD; if (!ghciInsertSymbolTable(oc->fileName, symhash, sname, - addr, false, type, oc)) { + addr, false, type, 0, oc)) { releaseOcInfo (oc); stgFree (oc->image); oc->image = NULL; @@ -2073,7 +2101,7 @@ ocGetNames_PEi386 ( ObjectCode* oc ) type |= SYM_TYPE_HIDDEN; if (!ghciInsertSymbolTable(oc->fileName, symhash, sname, - addr, false, type, oc)) + addr, false, type, 0, oc)) return false; break; @@ -2083,6 +2111,7 @@ ocGetNames_PEi386 ( ObjectCode* oc ) } if ((addr != NULL || isWeak) + && !common_already_defined && (!section || (section && section->kind != SECTIONKIND_IMPORT))) { /* debugBelch("addSymbol %p `%s' Weak:%lld \n", addr, sname, isWeak); */ sname = strdup (sname); @@ -2098,7 +2127,7 @@ ocGetNames_PEi386 ( ObjectCode* oc ) } if (! ghciInsertSymbolTable(oc->fileName, symhash, sname, addr, - isWeak, type, oc)) + isWeak, type, symSize, oc)) return false; } else { /* We're skipping the symbol, but if we ever load this ===================================== testsuite/tests/rts/linker/Makefile ===================================== @@ -152,3 +152,10 @@ T25191: "$(TEST_HC)" -c T25191_foo2.c -o foo2.o -v0 "$(TEST_HC)" T25191.hs -v0 ./T25191 + +.PHONY: T6107 +T6107: + "$(TEST_HC)" -c T6107_sym1.s -o T6107_sym1.o -v0 + "$(TEST_HC)" -c T6107_sym2.s -o T6107_sym2.o -v0 + "$(TEST_HC)" $(TEST_HC_OPTS) T6107.hs -o T6107 -v0 + ./T6107 ===================================== testsuite/tests/rts/linker/T6107.hs ===================================== @@ -0,0 +1,29 @@ +{-# LANGUAGE ForeignFunctionInterface, CPP #-} +-- Test that the RTS linker merges COMMON symbols from multiple object files. +-- Without the fix, loadObj of the second .o fails with a duplicate symbol error. +import Foreign.C.String +import Control.Monad + +-- Type of paths is different on Windows +#if defined(mingw32_HOST_OS) +type PathString = CWString +withPathString = withCWString +#else +type PathString = CString +withPathString = withCString +#endif + +main :: IO () +main = do + initLinker + r1 <- withPathString "T6107_sym1.o" loadObj + when (r1 /= 1) $ error "loadObj T6107_sym1.o failed" + r2 <- withPathString "T6107_sym2.o" loadObj + when (r2 /= 1) $ error "loadObj T6107_sym2.o failed" + r <- resolveObjs + when (r /= 1) $ error "resolveObjs failed" + putStrLn "OK" + +foreign import ccall "initLinker" initLinker :: IO () +foreign import ccall "loadObj" loadObj :: PathString -> IO Int +foreign import ccall "resolveObjs" resolveObjs :: IO Int ===================================== testsuite/tests/rts/linker/T6107.stdout ===================================== @@ -0,0 +1 @@ +OK ===================================== testsuite/tests/rts/linker/T6107_sym1.s ===================================== @@ -0,0 +1 @@ +.comm shared_var, 4 ===================================== testsuite/tests/rts/linker/T6107_sym2.s ===================================== @@ -0,0 +1 @@ +.comm shared_var, 4 ===================================== testsuite/tests/rts/linker/all.T ===================================== @@ -181,3 +181,11 @@ test('T25191', when(opsys('mingw32'), expect_broken(25191)) # not supported in the PE linker yet ], makefile_test, ['T25191']) + + +# Test that COMMON symbols from multiple object files are merged correctly +test('T6107', + [req_rts_linker, + extra_files(['T6107_sym1.s', 'T6107_sym2.s']) + ], + makefile_test, ['T6107']) View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/ad25af90bdbf1269ff9febbcbc9fffa… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/ad25af90bdbf1269ff9febbcbc9fffa… You're receiving this email because of your account on gitlab.haskell.org.

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