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[Git][ghc/ghc] Pushed new branch wip/fendor/dep-json-link-nodes
by Hannes Siebenhandl (＠fendor) 13 Oct '26

13 Oct '26

Hannes Siebenhandl pushed new branch wip/fendor/dep-json-link-nodes at Glasgow Haskell Compiler / GHC -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/tree/wip/fendor/dep-json-link-nodes You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

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[Git][ghc/ghc][wip/davide/windows-dlls_sysm-test_master] fixup! Add golden test for rts/RtsSymbols.c
by David Eichmann (＠DavidEichmann) 13 Oct '26

13 Oct '26

David Eichmann pushed to branch wip/davide/windows-dlls_sysm-test_master at Glasgow Haskell Compiler / GHC Commits: ae35f542 by David Eichmann at 2026-10-13T15:10:43+01:00 fixup! Add golden test for rts/RtsSymbols.c - - - - - 1 changed file: - testsuite/tests/rts/symbols/rts-check-symbols.sh Changes: ===================================== testsuite/tests/rts/symbols/rts-check-symbols.sh ===================================== @@ -10,14 +10,57 @@ OBSERVED_SYMBOLS=observed_symbols.txt # Get rts Symbols listed in RtsSymbols.c ./Main dump | sort > $DECLARED_SYMBOLS -# Get rts DLL exports from the DLL -# Match e.g.: -# libHSrts-1.0.3-ghc9.15.20260710.dll => /home/alice/s p a c e/myApp/bin/libHSrts-1.0.3-ghc9.15.20260710.dll (0x7ffebc9a0000) -RTS_DYLIB_PATH=$(ldd ./Main | awk '/^[[:space:]]*libHSrts-.* => .+$/ { - sub(/^[[:space:]]*libHSrts-.* => /, "") - sub(/ $[^(]*$$/, "") - print -}') +# Find the path of the RTS shared object that ./Main is linked against +if command -v ldd > /dev/null 2>&1; then + # Match e.g.: + # libHSrts-1.0.3-ghc9.15.20260710.so => /home/alice/s p a c e/myApp/lib/libHSrts-1.0.3-ghc9.15.20260710.so (0x7ffebc9a0000) + RTS_DYLIB_PATH=$(ldd ./Main | awk '/^[[:space:]]*libHSrts-.* => .+$/ { + sub(/^[[:space:]]*libHSrts-.* => /, "") + sub(/ $[^(]*$$/, "") + print + }') +elif command -v otool > /dev/null 2>&1; then + # macOS has no ldd. Use otool to find the RTS install name, e.g.: + # @rpath/libHSrts-1.0.3-ghc9.15.20260710.dylib (compatibility version 0.0.0, current version 0.0.0) + RTS_INSTALL_NAME=$(otool -L ./Main | awk '/^[[:space:]]*[^[:space:]].*\/libHSrts-[^\/]*\.dylib $/ { + sub(/^[[:space:]]*/, "") + sub(/ \([^(]*$$/, "") + print + exit + }') + + case "$RTS_INSTALL_NAME" in + @rpath/*) + # Resolve @rpath against the LC_RPATH entries of ./Main e.g.: + # cmd LC_RPATH + # cmdsize 120 + # path /Users/alice/s p a c e/lib/rts-1.0.3 (offset 12) + MAIN_DIR=$(cd "$(dirname ./Main)" && pwd) + RTS_DYLIB_PATH="not found" + while IFS= read -r RPATH; do + RPATH="${RPATH/#@loader_path/$MAIN_DIR}" + RPATH="${RPATH/#@executable_path/$MAIN_DIR}" + CANDIDATE="$RPATH/${RTS_INSTALL_NAME#@rpath/}" + if [ -f "$CANDIDATE" ]; then + RTS_DYLIB_PATH="$CANDIDATE" + break + fi + done < <(otool -l ./Main | awk ' + $1 == "cmd" { in_rpath = ($2 == "LC_RPATH") } + in_rpath && $1 == "path" { + sub(/^[[:space:]]*path /, "") + sub(/ $offset [0-9]+$$/, "") + print + }') + ;; + *) + RTS_DYLIB_PATH="$RTS_INSTALL_NAME" + ;; + esac +else + echo "Neither ldd nor otool is available to find the RTS DSO" 1>&2 + exit 1 +fi if [ -z "$RTS_DYLIB_PATH" -o "$RTS_DYLIB_PATH" = "not found" ]; then echo "Could not find path to RTS DSO: \"$RTS_DYLIB_PATH\"" 1>&2 View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/ae35f54211a6c26c1ef61fba994afae… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/ae35f54211a6c26c1ef61fba994afae… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

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[Git][ghc/ghc][wip/marge_bot_batch_merge_job] 9 commits: Remove the Eq and Ord instances for ForAllTyFlag
by Marge Bot (＠marge-bot) 13 Oct '26

13 Oct '26

Marge Bot pushed to branch wip/marge_bot_batch_merge_job at Glasgow Haskell Compiler / GHC Commits: 61ceab17 by Simon Peyton Jones at 2026-10-13T09:47:50-04:00 Remove the Eq and Ord instances for ForAllTyFlag In Note [Comparing visibility] in GHC.Core.TyCo.Compare we read that "we always compare ForAllTyFlags with `eqForAllVis` or `cmpForAllVis`" But alas there was an Eq and Ord instance for ForAllTyFlag, which made it impossible to check this claim. So I made these changes: * Move the definition of ForAllTyFlag and its related functions from L.H.S.Specificity (where it did not belong, since L.H.S didn't use it) into GHC.Types.Var. * Remove the Eq and Ord instances for ForAllTyFlag * Deal with the fallout, by using `eqForAllVis` or related functions. * In interface files we use IfaceType as a key for a de-deduplication map See Note [Deduplication during iface binary serialisation] in GHC.Iface.Binary. For this we need /exact/ comparison, so we use a newtype wrapper for IfaceForAllTyFlag, and give use `cmpForAllTyFlagExactly` to implement its Ord instance. Tiresome but easy. * Rename `toIfaceForAllBndrs` to `toIfaceForAllTyBndrs` - - - - - 51a7421d by Simon Peyton Jones at 2026-10-13T09:47:50-04:00 Refactor type and coercion substitution This MR refactors type and coercion substitution so that they use TyCoMapper, rather than hand-rolled code. Fundamentally it's a simple idea, but I had to do quite a bit of refactoring to make it fly. I got Claude to help me this this refactoring, but I paid careful attention to every line of code. Main changes: * New module GHC.Core.TyCo.Make which defines TyCoMapper, and a bunch of other simple "smart constructors" for types and coercions. See GHC.Core.TyCo.Rep Note [The Type-related module hierarchy], esp (TRM1) * The new TyCoMapper has new fields `tcm_tcapp_ty` and `tcm_tcapp_co` to handle type-constructor applications. These replace `tcm_tycon`. * Rewrite GHC.Core.TyCo.Subst to use TyCoMapper * Rewrite GHC.Core.Type.expandTypeSynonyms to use TyCoMapper. * Implement `seqType` and `seqCo` with TyCoFolder. To to this I had to add a `tcf_lit` field to TyCoFolder. * A new module GHC.Utils.StrictIdentity to define a strict identity monad, which itself is used for substTyCoMapper :: TyCoMapper Subst StrictIdentity * I removed an apparently-unused instance for Binary Levity Refactoring `seq` functions * In GHC.Core.Seq, redefine `seqOneShot`, `seqRuleInfo`, and friends to return `SeqResult`, a new type defined in GHC.Types.Baseic, rather than `()`. We can define a Monoid instance for `SeqResult` that does the right thing. * This has knock-on effects across the compiler. - - - - - 29627cb5 by Simon Peyton Jones at 2026-10-13T09:47:50-04:00 Refactor TyCoMapper to take a single monad; add StrictReaderT TyCoMapper used to be parameterised over both an environment and a monad, with fields like tcm_tyvar :: env -> TyVar -> m Type Now it is parameterised over just the monad: tcm_tyvar :: TyVar -> m Type If the mapping needs an environment, `m` is a reader monad over that environment. Many uses (e.g. zonkTcTypeMapper, swizzleMapper) need no environment at all, and used to pass a dummy (). The binder field becomes tcm_tycobinder :: forall r. TyCoVar -> ForAllTyFlag -> (TyCoVar -> m r) -> m r and runs the continuation in the extended environment. mapTyCoX is gone; only mapTyCo remains. To make this efficient, the reader monad must use the one-shot trick and be strict in the environment. So: * New module GHC.Utils.Monad.StrictReader defines newtype StrictReaderT r m a with hand-written instances. The builder of the pattern synonym `StrictReaderT` is a smart constructor that adds both `oneShot` and a bang on the environment, so every StrictReaderT computation is strict in the environment. See Note [Instances for StrictReaderT]. * ZonkT becomes type ZonkT = StrictReaderT ZonkEnv ZonkM becomes type ZonkM = StrictReaderT ZonkGblEnv IO replacing their own hand-written instances. * Substitution uses type SubstM = StrictReaderT Subst StrictIdentity substTyCoMapper :: TyCoMapper SubstM and similarly expandTypeSynonymMapper. * zonk_tycomapper :: TyCoMapper (ZonkT TcM) is now much simpler. * swizzleMapper uses StrictIdentity rather than Identity. * Module renaming, so that the strict monads are all peers in GHC.Utils.Monad: GHC.Utils.StrictIdentity ==> GHC.Utils.Monad.StrictIdentity GHC.Utils.Monad.State.Strict ==> GHC.Utils.Monad.StrictState alongside the new GHC.Utils.Monad.StrictReader. Co-Authored-By: Claude Opus 5.5 <noreply(a)anthropic.com> - - - - - 9a5e5112 by Simon Jakobi at 2026-10-13T09:47:53-04:00 testsuite: Line-buffer the driver's stdout Python block-buffers stdout when it is a pipe. This is the case for example in CI. As a result there is often no indication of progress at all until the run ends. To fix this, we configure it explicitly to use line buffering instead. stderr is reconfigured too, for consistency: Python line-buffers it by default since 3.9. The type-ignores are for mypy, which types these handles as TextIO — an interface without reconfigure. Fixes #12934. Assisted-by: Claude Fable 5 - - - - - c4d602ed by Florian Ragwitz at 2026-10-13T09:47:54-04:00 hpc: Improve coverage semantics for instance methods and instances Users care about which of their explicitly written methods are or aren't covered, not whether all of the inherited methods are covered as well. Those should be covered where they are implemented. We therefore skip generating top-level boxes for inherited methods which will appear as uncovered with no clear indication as to why, and no way to fix other than exercising code the user has not written. Previously, top-level boxes for those inherited methods would use the instance head as their source span. Now that those boxes are gone, we can use that source span for another purpose: We introduce a new top-level box for each class instance with its instance head as the source span, and use that to indicate whether or not an instance has been covered at all. We do this by making any method of the instance, inherited/generated or otherwise, tick the box for the instance head. Excluded from this are methodless classes, which could never be covered using the current mechanism. This could be improved upon further. These changes apply to ticking for program coverage only, and don't affect source notes. Additionally, we update the scope of record selector ticking to be limited to program coverage as well, as the oversight to also extend it to source notes has previously caused bugs and because record selector ticking is coverage-specific. Fixes #17155, #15932. - - - - - 3344e14b by Simon Peyton Jones at 2026-10-13T09:47:55-04:00 Refactor fundeps again This MR fixes #27828; there was a bad scoping error in `trim_qtvs`. The main changes are * Refactor `trim_qtvs` completely to eliminate the bug. * Remove a redundant `apartnessCheck` from `mkTopOpenFamEqFDs`. * Lots of improvements to the Notes in FunDeps.hs I also did a couple of pure refactors: * I realised that we were carefully caching `cab_incomps` in each `CoAxBranch`, to make it more efficient to reduce a type family application, but we were not doing the same thing when computing relevance for functional dependencies; see Note [Relevance] in GHC.Tc.Solver.FunDeps. So I added `cab_overlaps`, which is now used in `noEarlierMatch`. * Use a proper data types, `AmIUnifying` and `OuterKindsFlag`, for two previously-Boolean arguments to `tc_unify_tys`. This is a pure refactor. - - - - - 7cf86776 by Simon Peyton Jones at 2026-10-13T09:47:56-04:00 Refactor and simplify solver's unification code Ticket #27844 showed that GHC's constraint solver could miss an occurs check, and thereby build an infinite type. This patch significantly simplifes the code in GHC.Tc.Solver.Equality.canEqCanLHSFinish_try_unification GHC.Tc.Solver.Equality.canEqCanLHSFinish_no_unification It is now significantly simpler, and requires much less subtle reasoning to understand. Main changes * If `canEqCanLHSFinish_try_unification` fails to unify, it now /always/ calls `canEqCanLHSFinish_no_unification` rather than trying to finish the job itself. * `GHC.Tc.Solver.Monad.checkTypeEq` is moved from Monad into Equality, and renamed to `GHC.Tc.Solver.Equality.checkTypeEqNoUnification`. * `canEqCanLHSFinish_no_unification` calls `checkTypeEqNoUnification` to test the invariants for an inert equality. Before this MR there was a special case for `do_not_prevent_rewriting`, but that has gone; instead it's just a consequence of the flags passed to `checkTyEqRhs`, documented in the `PuOK` case of `canEqCanLHSFinish_no_unification`. * There is only one bit of "swap back" code, in `finish_no_unify` in `canEqCanLHSFinish_try_unification. Previously this code was duplicated. * `kickOutAfterFillingCoercionHole` should account for equalities with a TyFamLHS. See (KOC5) in Note [Kick out after filling a coercion hole] * No need to gather coercion holes in the `PuOK` case of `canEqCanLHSFinish_no_unification`. See documentation with that code. - - - - - 314eb0f9 by Simon Peyton Jones at 2026-10-13T09:47:56-04:00 One line fix to fallout from ...#27731, !16564, simplifying Tc.Errors machinery There was an over-eager assert! - - - - - 7d6f20e0 by Sylvain Henry at 2026-10-13T09:48:25-04:00 NCG x86: track the current block after word-to-float conversion (#27915) On x86-64, genWordToFloat introduces new basic blocks, but it was dispatched via genSimplePrim, which assumes no new blocks. The new current block was not given back to stmtsToInstrs, so a second conversion in the same Cmm block updated the CFG relative to a stale block id. This caused the panic "Can't find weight for edge that should have one" when the register allocator inserted a fixup block. genWordToFloat now returns the new current block and MO_UF_Conv is handled with the other block-introducing primops in genPrim. See Note [Keeping track of the current block]. Co-Authored-By: Claude Opus 5.5 <noreply(a)anthropic.com> - - - - - 126 changed files: - + changelog.d/27915 - + changelog.d/T27828 - + changelog.d/T27844 - + changelog.d/hpc-classinsts - compiler/GHC/Builtin/WiredIn/Prim.hs - compiler/GHC/Builtin/WiredIn/Types/Box.hs - compiler/GHC/Cmm/GenericOpt.hs - compiler/GHC/Cmm/UniqueRenamer.hs - compiler/GHC/CmmToAsm/Dwarf/Types.hs - compiler/GHC/CmmToAsm/Monad.hs - compiler/GHC/CmmToAsm/Reg/Graph/Spill.hs - compiler/GHC/CmmToAsm/Reg/Graph/SpillClean.hs - compiler/GHC/CmmToAsm/Reg/Graph/SpillCost.hs - compiler/GHC/CmmToAsm/Reg/Graph/Stats.hs - compiler/GHC/CmmToAsm/Reg/Linear/State.hs - compiler/GHC/CmmToAsm/Reg/Linear/Stats.hs - compiler/GHC/CmmToAsm/Reg/Liveness.hs - compiler/GHC/CmmToAsm/Wasm/Asm.hs - compiler/GHC/CmmToAsm/Wasm/Types.hs - compiler/GHC/CmmToAsm/X86/CodeGen.hs - compiler/GHC/CmmToC.hs - compiler/GHC/Core/Coercion.hs - compiler/GHC/Core/Coercion.hs-boot - compiler/GHC/Core/Coercion/Axiom.hs - compiler/GHC/Core/Coercion/Opt.hs - compiler/GHC/Core/DataCon.hs - compiler/GHC/Core/FamInstEnv.hs - compiler/GHC/Core/Lint.hs - compiler/GHC/Core/Map/Type.hs - compiler/GHC/Core/Opt/Arity.hs - compiler/GHC/Core/Opt/CallerCC.hs - compiler/GHC/Core/Opt/Exitify.hs - compiler/GHC/Core/Opt/Specialise.hs - compiler/GHC/Core/Reduction.hs - compiler/GHC/Core/Seq.hs - compiler/GHC/Core/TyCo/Compare.hs - compiler/GHC/Core/TyCo/FVs.hs - + compiler/GHC/Core/TyCo/Make.hs - + compiler/GHC/Core/TyCo/Make.hs-boot - compiler/GHC/Core/TyCo/Ppr.hs - compiler/GHC/Core/TyCo/Rep.hs - compiler/GHC/Core/TyCo/Rep.hs-boot - compiler/GHC/Core/TyCo/Subst.hs - compiler/GHC/Core/Type.hs - compiler/GHC/Core/Type.hs-boot - compiler/GHC/Core/Unify.hs - compiler/GHC/CoreToIface.hs - compiler/GHC/CoreToIface.hs-boot - compiler/GHC/Driver/Downsweep.hs - compiler/GHC/Driver/Main/Compile.hs - compiler/GHC/HsToCore.hs - compiler/GHC/HsToCore/Ticks.hs - compiler/GHC/Iface/Decl.hs - compiler/GHC/Iface/Ext/Types.hs - compiler/GHC/Iface/Ext/Utils.hs - compiler/GHC/Iface/Syntax.hs - compiler/GHC/Iface/Type.hs - compiler/GHC/Iface/Type.hs-boot - compiler/GHC/IfaceToCore.hs - compiler/GHC/Runtime/Heap/Inspect.hs - compiler/GHC/Stg/BcPrep.hs - compiler/GHC/Stg/Debug.hs - compiler/GHC/Stg/EnforceEpt/Rewrite.hs - compiler/GHC/Stg/EnforceEpt/TagSig.hs - compiler/GHC/Stg/Subst.hs - compiler/GHC/Tc/Deriv/Functor.hs - compiler/GHC/Tc/Errors.hs - compiler/GHC/Tc/Errors/Ppr.hs - compiler/GHC/Tc/Gen/App.hs - compiler/GHC/Tc/Instance/FunDeps.hs - compiler/GHC/Tc/Solver/Equality.hs - compiler/GHC/Tc/Solver/FunDeps.hs - compiler/GHC/Tc/Solver/InertSet.hs - compiler/GHC/Tc/Solver/Monad.hs - compiler/GHC/Tc/TyCl.hs - compiler/GHC/Tc/TyCl/Instance.hs - compiler/GHC/Tc/Types/Constraint.hs - compiler/GHC/Tc/Utils/Unify.hs - compiler/GHC/Tc/Zonk/Env.hs - compiler/GHC/Tc/Zonk/Monad.hs - compiler/GHC/Tc/Zonk/TcType.hs - compiler/GHC/Tc/Zonk/Type.hs - compiler/GHC/Types/Arity.hs - compiler/GHC/Types/Basic.hs - compiler/GHC/Types/Cpr.hs - compiler/GHC/Types/Demand.hs - compiler/GHC/Types/Id/Info.hs - compiler/GHC/Types/Name/Env.hs - compiler/GHC/Types/Name/Occurrence.hs - compiler/GHC/Types/Unique/DSM.hs - compiler/GHC/Types/Unique/FM.hs - compiler/GHC/Types/Unique/Map.hs - compiler/GHC/Types/Unique/Set.hs - compiler/GHC/Types/Unique/Supply.hs - compiler/GHC/Types/Var.hs - compiler/GHC/Types/Var.hs-boot - compiler/GHC/Types/Var/Set.hs - compiler/GHC/Utils/Binary.hs - + compiler/GHC/Utils/Monad/StrictIdentity.hs - + compiler/GHC/Utils/Monad/StrictReader.hs - compiler/GHC/Utils/Monad/State/Strict.hs → compiler/GHC/Utils/Monad/StrictState.hs - compiler/GHC/Utils/Outputable.hs - compiler/Language/Haskell/Syntax/Specificity.hs - compiler/ghc.cabal.in - testsuite/driver/runtests.py - + testsuite/tests/codeGen/should_run/T27915.hs - + testsuite/tests/codeGen/should_run/T27915.stdout-ws-32 - + testsuite/tests/codeGen/should_run/T27915.stdout-ws-64 - testsuite/tests/codeGen/should_run/all.T - testsuite/tests/count-deps/CountDepsParser.stdout - + testsuite/tests/hpc/instmeths/instmeths.hs - + testsuite/tests/hpc/instmeths/instmeths.stdout - + testsuite/tests/hpc/instmeths/test.T - + testsuite/tests/indexed-types/should_compile/T27828.hs - + testsuite/tests/indexed-types/should_compile/T27828a.hs - + testsuite/tests/indexed-types/should_compile/T27828b.hs - testsuite/tests/indexed-types/should_compile/all.T - testsuite/tests/indexed-types/should_fail/T9662.stderr - testsuite/tests/simplCore/should_compile/T22375.stderr - testsuite/tests/simplCore/should_compile/T22375DataFamily.stderr - testsuite/tests/typecheck/should_fail/T12785b.stderr - + testsuite/tests/typecheck/should_fail/T27844.hs - + testsuite/tests/typecheck/should_fail/T27844.stderr - testsuite/tests/typecheck/should_fail/all.T - utils/check-exact/Utils.hs - utils/haddock/haddock-api/src/Haddock/Backends/Hyperlinker/Utils.hs The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/48dc29da41aabddb6c446cf63ceff4… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/48dc29da41aabddb6c446cf63ceff4… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

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[Git][ghc/ghc][wip/andrea/with-signal-handlers] 13 commits: Do not leave standard file descriptors free at startup (#24450)
by Andrea Vezzosi (＠trac-Saizan) 13 Oct '26

13 Oct '26

Andrea Vezzosi pushed to branch wip/andrea/with-signal-handlers at Glasgow Haskell Compiler / GHC Commits: 8d49ed42 by Kazu Yamamoto at 2026-10-06T19:37:25-04:00 Do not leave standard file descriptors free at startup (#24450) A process may be started with stdout closed -- `prog >&-` from a shell does exactly that. Nothing then reserves descriptor 1, and open(), pipe() and socket() hand out the lowest free descriptor, so the next descriptor the runtime creates for itself takes it: the ticker's pipe, or a capability's IO manager control pipe. 'GHC.Internal.IO.StdHandles.stdout' is a CAF, built the first time the program writes to stdout, which is long after that has happened. It builds a 'Handle' over descriptor 1, which now belongs to the runtime, and nothing reports an error because the descriptor is perfectly good. The program then writes its output into the runtime's own plumbing. What that looks like from the outside is a hang. The descriptor the Handle has taken over is the read end of a pipe, so poll() for POLLOUT on it never says yes and epoll_ctl() accepts a registration for it; the thread waiting to write blocks for ever. Closing the Handle at exit closes the runtime's descriptor, which is worse: the ticker then fails on every tick. 'hs_init_ghc' now opens /dev/null onto whichever of descriptors 0, 1 and 2 are closed, before the runtime creates any descriptor of its own. Each is opened for the access that descriptor would normally have, read-only for 0 and write-only for 1 and 2, so that writing to 'stdin' or reading from 'stdout' still fails rather than quietly succeeding against /dev/null. See Note [Standard file descriptors must be open]. Moving only the descriptors the runtime opens would not do: the first file the program itself opened would land on the free number instead. The fix has to leave no free number. A program run this way therefore finds stdout connected to /dev/null rather than failing with EBADF on the first write, which is what such a program would get from most other language runtimes. Co-Authored-By: Claude Opus 5 (1M context) <noreply(a)anthropic.com> - - - - - 65bcf9e9 by Simon Jakobi at 2026-10-06T19:38:09-04:00 changelog: Repair the sentence describing #27477 The description read "programs using could crash", the object of "using" having been lost. The synopsis already says which programs are affected, so drop the dangling word. Assisted-by: Claude Fable 5.1 - - - - - 15ece296 by mangoiv at 2026-10-08T15:14:56-04:00 ci: move hadrian/ghci into the lint category so it can be picked up by more runners Fixes #27817 - - - - - c0823135 by mangoiv at 2026-10-08T15:14:56-04:00 ci: make lint-adjacent jobs into platform independent - move lint jobs into lint-anyarch tag - unify lint jobs under the same platform independent container - - - - - f76464cf by Zubin Duggal at 2026-10-08T15:15:39-04:00 DmdAnal: Make AbsDmd neutral in maxDmd fixes #27845 - - - - - ffa56ae4 by sheaf at 2026-10-09T17:15:59+02:00 Preserve sign of zero when parsing -0.0# This commit leverages the recently added GHC.Types.Literal.Floating module in order to preserve the sign of negative zero from source-written floating-point literals. Fixes #27545 - - - - - d538cac9 by Facundo Domínguez at 2026-10-09T20:26:38-04:00 Propagate annotations to simple interfaces This allows annotations to be visible to plugins when run by haddock. The LiquidHaskell plugin needs the annotations, in particular. Fixes #26761 - - - - - 32c4f4ab by meooow25 at 2026-10-09T20:27:28-04:00 Bump containers submodule to 0.8.1 And fix affected tests. * T4086a: containers depends on template-haskell-lift now instead of template-haskell. * T22611: Updated to be less dependent on containers internals. - - - - - c786065e by sheaf at 2026-10-09T20:28:20-04:00 Use an explicit pattern match in toIfaceIdDetails The old wildcard pattern let this code bit rot: it did not properly account for recently added 'IdDetails' such as 'RepPolyId', which resulted in spurious 'pprTrace' messages that could even pollute HLS sessions. Fixes #23785 - - - - - e7cacf59 by sheaf at 2026-10-09T20:29:09-04:00 Take into account ifKind in freeNamesIfDecl Commit 3c2f4bb4 added the 'ifKind' field to various constructors of 'IfaceDecl', which preserves the original kind (before type synonym expansion) for better error messages. However, that commit forgot to update 'freeNamesIfDecl' correspondingly. This could result in a "urk! lookup local fingerpring" crash when e.g. a type's kind uses a type synonym defined later, as we failed to add a dependency on the type synonym during dependency analysis. Fixes #27916 - - - - - 41e80f41 by Simon Peyton Jones at 2026-10-11T14:38:51-04:00 Simplify the error-suppression mechanism in GHC.Tc.Errors In `GHC.Tc.Errors.reportWanteds` we suppress some errors in favour of others. But the mechanism had grown crufty, and #27331 exposed a bug. This MR makes it simpler and more uniform, by doing everything via the `ei_suppress` field of the ErrorItem. Claude then found another closely-related bug (see the review linked on !16564). That bug is immortalised in new test T18851d. I'm still not happy with `ignoreConstraint` but we can worry about that another day; I have not touched it. Main changes * Instead of /predicting/ when an error will be reported, we set `cec_error_reported` when an error is /actually/ reported. (I renamed it from `cec_suppress` to reflect this change.) Now errors are suppressed only when a preceding error has actually been reported. Simpler and more robust. See `Note [cec_error_reported: suppressing less-serious errors]` The big changes are in `reportWanteds` which looks very different. * New `Note [ei_suppress: suppressing confusing errors]` describes the (quite separate) `ei_suppress` mechanism for suppressing confusing errors, mainly arising from non-empty rewriter sets * In `tryTypeClassDefaulting`, instead of switching off type-class defaulting if there is an insoluble /anywhere/, we just switch it off locally when we find an insoluble sub-tree. See Note [When to do type-class defaulting] and (W5) in Note [ApproximateWC] * Greatly simplify `insolubleWantedCt`. * I made type-class-defaulting be a bit more eager, only switched off when a peer or ancestor (but not child) constraint is insoluble. See Note [When to do type-class defaulting]. Small refactorings * Rename `askNoErrs` to `askErrsFound` and flip its polarity * The code for "check if ei_suppress is true of all items" code is moved to `mkErrorItems` rather than in the large `reportWanteds`. * Code for `has_gadt_match` moves to `mkGivenErrorReporter`, rather than polluting the large `reportWanteds`. * Many tests with `-fdefer-type-errors` get more warnings, especially about ambiguous (Num a) constraints. This is by-design: see Note [Always warn with -fdefer-type-errors]. Previously GHC was not honouring this Note but now it is, hence the extra errors. - - - - - f217fc31 by Cheng Shao at 2026-10-11T14:39:33-04:00 compiler: ensure cross ghc --info output target unit ids Previously, for cross ghcs, the base/ghc/ghc-internal unit ids in --info output do not match the target unit ids reported by ghc-pkg, breaking cross ghc release builds with hash-unit-ids when being used with cabal 3.18. This patch fixes it by making --info output target unit ids. Fixes #27919. Co-authored-by: Codex <codex(a)openai.com> - - - - - fe0825de by Andrea Vezzosi at 2026-10-13T15:45:14+02:00 add runGhcWithSignalHandlers and remove handling from runGhc[T] it only ever makes sense to call `withSignalHandlers` from `main`, otherwise signals can be too easily swallowed without notification to the rest of your process. This commit takes withSignalHandlers out of `runGhc/runGhcT` and provides `runGhcWithSignalHandlers` for the old behaviour. - - - - - 122 changed files: - .gitlab-ci.yml - .gitlab/hello.hs - + changelog.d/24450 - + changelog.d/26761 - + changelog.d/27845 - + changelog.d/T23785 - + changelog.d/T27545 - + changelog.d/T27731 - + changelog.d/T27916 - + changelog.d/T4162 - + changelog.d/fix-cross-ghc-info-unit-id - changelog.d/fix-parallel-gc-selector-race-27477 - compiler/GHC.hs - compiler/GHC/Builtin/WiredIn/Ids.hs - compiler/GHC/Core/Make.hs - compiler/GHC/CoreToIface.hs - compiler/GHC/Driver/Session.hs - compiler/GHC/Hs/Lit.hs - compiler/GHC/HsToCore/Match/Literal.hs - compiler/GHC/Iface/Decl.hs - compiler/GHC/Iface/Syntax.hs - compiler/GHC/Iface/Tidy.hs - compiler/GHC/Rename/Module.hs - compiler/GHC/Settings.hs - compiler/GHC/Settings/IO.hs - compiler/GHC/Tc/Errors.hs - compiler/GHC/Tc/Errors/Ppr.hs - compiler/GHC/Tc/Errors/Types.hs - compiler/GHC/Tc/Instance/Family.hs - compiler/GHC/Tc/Solver/Default.hs - compiler/GHC/Tc/Solver/Equality.hs - compiler/GHC/Tc/Types/Constraint.hs - compiler/GHC/Tc/Utils/Monad.hs - compiler/GHC/Types/Demand.hs - compiler/GHC/Utils/Panic.hs - compiler/Language/Haskell/Syntax/Lit.hs - distrib/configure.ac.in - ghc/Main.hs - hadrian/bindist/Makefile - hadrian/bindist/config.mk.in - hadrian/src/Rules/BinaryDist.hs - hadrian/src/Rules/Generate.hs - libraries/containers - linters/lint-codes/LintCodes/Static.hs - rts/RtsStartup.c - + testsuite/tests/dmdanal/should_run/T27845.hs - + testsuite/tests/dmdanal/should_run/T27845.stdout - + testsuite/tests/dmdanal/should_run/T27845_Lib.hs - + testsuite/tests/dmdanal/should_run/T27845b.hs - + testsuite/tests/dmdanal/should_run/T27845b.stdout - + testsuite/tests/dmdanal/should_run/T27845b_Lib.hs - testsuite/tests/dmdanal/should_run/all.T - + testsuite/tests/ghc-api/T4162.hs - + testsuite/tests/ghc-api/T4162.stdout - testsuite/tests/ghc-api/all.T - testsuite/tests/ghci/prog020/ghci.prog020a.stderr - testsuite/tests/ghci/prog020/ghci.prog020b.stderr - testsuite/tests/ghci/prog021/prog021a.stderr - testsuite/tests/ghci/prog021/prog021b.stderr - testsuite/tests/ghci/prog022/ghci.prog022a.stderr - testsuite/tests/ghci/prog022/ghci.prog022b.stderr - testsuite/tests/ghci/prog022/ghci.prog022c.stderr - testsuite/tests/ghci/prog022/ghci.prog022d.stderr - testsuite/tests/ghci/prog022/ghci.prog022e.stderr - testsuite/tests/ghci/prog022/ghci.prog022f.stderr - testsuite/tests/ghci/scripts/Defer02.stderr - testsuite/tests/module/mod130.stderr - + testsuite/tests/numeric/should_run/T27545.hs - + testsuite/tests/numeric/should_run/T27545.stdout - testsuite/tests/numeric/should_run/all.T - testsuite/tests/overloadedstrings/should_fail/T25926.stderr - testsuite/tests/overloadedstrings/should_fail/T27124.stderr - testsuite/tests/package/T4806a.stderr - testsuite/tests/package/all.T - testsuite/tests/patsyn/should_fail/records-nofieldselectors.stderr - + testsuite/tests/plugins/T26761.hs - + testsuite/tests/plugins/T26761.stderr - + testsuite/tests/plugins/T26761Plugin.hs - + testsuite/tests/plugins/T26761a.hs - testsuite/tests/plugins/all.T - testsuite/tests/printer/T17697.stderr - testsuite/tests/rename/should_fail/T15607.stderr - testsuite/tests/rename/should_fail/T19843b.stderr - + testsuite/tests/rts/T24450.hs - + testsuite/tests/rts/T24450.stderr - testsuite/tests/rts/all.T - testsuite/tests/safeHaskell/ghci/p4.stderr - testsuite/tests/safeHaskell/ghci/p6.stderr - testsuite/tests/simplCore/should_compile/T22611.hs - testsuite/tests/simplCore/should_compile/T22611.stderr - + testsuite/tests/simplCore/should_compile/T22611a.hs - testsuite/tests/simplCore/should_compile/all.T - testsuite/tests/typecheck/should_compile/T11254.stderr - testsuite/tests/typecheck/should_compile/T15370.stderr - + testsuite/tests/typecheck/should_compile/T27916.hs - testsuite/tests/typecheck/should_compile/all.T - testsuite/tests/typecheck/should_compile/valid_hole_fits.stderr - testsuite/tests/typecheck/should_fail/ClassOperator.stderr - testsuite/tests/typecheck/should_fail/DoExpansion2.stderr - testsuite/tests/typecheck/should_fail/DoExpansion3.stderr - testsuite/tests/typecheck/should_fail/FunDepOrigin1b.hs - testsuite/tests/typecheck/should_fail/T18851.stderr - + testsuite/tests/typecheck/should_fail/T18851e.hs - + testsuite/tests/typecheck/should_fail/T18851e.stderr - + testsuite/tests/typecheck/should_fail/T18851f.hs - + testsuite/tests/typecheck/should_fail/T18851f.stderr - testsuite/tests/typecheck/should_fail/T22940.stderr - testsuite/tests/typecheck/should_fail/T26823.stderr - + testsuite/tests/typecheck/should_fail/T27731.hs - + testsuite/tests/typecheck/should_fail/T27731.stderr - testsuite/tests/typecheck/should_fail/T5691.stderr - testsuite/tests/typecheck/should_fail/T7437.stderr - testsuite/tests/typecheck/should_fail/all.T - testsuite/tests/typecheck/should_fail/mc24.stderr - testsuite/tests/typecheck/should_fail/tcfail019.stderr - testsuite/tests/typecheck/should_fail/tcfail189.stderr - utils/check-exact/Parsers.hs - utils/check-ppr/Main.hs - utils/count-deps/Main.hs - utils/dump-decls/Main.hs - utils/haddock/haddock-api/src/Haddock.hs - utils/haddock/haddock-api/test/Haddock/Backends/Hyperlinker/ParserSpec.hs The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/1091494a093356c0c10d70e88ddeeb… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/1091494a093356c0c10d70e88ddeeb… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

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[Git][ghc/ghc][wip/fendor/dep-json] 4 commits: Add `-dep-json` flag to `ghc -M`
by Hannes Siebenhandl (＠fendor) 13 Oct '26

13 Oct '26

Hannes Siebenhandl pushed to branch wip/fendor/dep-json at Glasgow Haskell Compiler / GHC Commits: f53755b8 by fendor at 2026-10-13T15:25:50+02:00 Add `-dep-json` flag to `ghc -M` Add an optional flag to `ghc -M` that allows to write the dependency information in JSON Lines format. The JSON Lines format enables us to stream the output of the dependency generation to a consumer. The output of `-dep-json` is streamed to a temporary file and then copied to the final destination to avoid partial writes. Each line contains one of two possible json objects: 1. A Home Unit Dependency * Contains the name of the home module, its unit, where it is located, whether a preprocessor is used, and all of its imports. Importantly, the imports include `-XExplicitLevelImports` information. * If requested via `-include-pkg-deps`, includes imports of external units, e.g. modules from `base`. * If requested via `-include-cpp-deps`, files included via CPP. 2. External Unit Dependency * Only if `-include-pkg-deps` is given * Contains unit-id, its package name and package id. - - - - - e07bb912 by fendor at 2026-10-13T15:25:50+02:00 Add multiple home unit support to `ghc -M` Allows to process the module graph of multiple home units at once using the same syntax as `--make` and `--interactive`: ghc -M -unit @unitA -unit @unitB The semantics are identical to `--make` and `--interactive`. Each home unit can declare individually to use `-include-cpp-deps` and `-include-pkg-deps`. However, there can only be one output file, and `-dep-json` and `-dep-makefile` can only be provided at the top of the cli invocation. We introduce a new GHC API `doMkDepend` that allows to use multiple home units conveniently. The output of `-dep-json` and `-dep-makefile` does not change, since we were careful to choose a format that supports multiple home units from the start. Single home units are still accepted like before with no changes. - - - - - d32644c4 by fendor at 2026-10-13T15:25:50+02:00 Deprecate `doMkDependHS` in favour of `doMkDepend` - - - - - d55ea6d8 by fendor at 2026-10-13T15:25:50+02:00 Improve `ghc -M` test-suite Adds a more extensive test-suite for `ghc -M` mode. Introduce a dedicated test mode for running `ghc -M` tests more conveniently. Adds lots of normalizers that help to write `ghc -M` tests in a platform independent manner. Adds utility scripts that help format the output of `ghc -M`. - - - - - 61 changed files: - + changelog.d/make-depends-json - compiler/GHC/Driver/DynFlags.hs - compiler/GHC/Driver/MakeFile.hs - compiler/GHC/Driver/Session.hs - compiler/GHC/Driver/Session/Units.hs - compiler/GHC/Utils/Json.hs - + docs/users_guide/make-depends-json-schema-1_0.json - docs/users_guide/separate_compilation.rst - ghc/Main.hs - testsuite/driver/testglobals.py - testsuite/driver/testlib.py - testsuite/tests/driver/mkdepend/Makefile - + testsuite/tests/driver/mkdepend/README.md - testsuite/tests/driver/mkdepend/A.hs → testsuite/tests/driver/mkdepend/T24384/A.hs - testsuite/tests/driver/mkdepend/C.hs → testsuite/tests/driver/mkdepend/T24384/C.hs - testsuite/tests/driver/mkdepend/C.hs-boot → testsuite/tests/driver/mkdepend/T24384/C.hs-boot - testsuite/tests/driver/mkdepend/D.hs → testsuite/tests/driver/mkdepend/T24384/D.hs - testsuite/tests/driver/mkdepend/E.hs → testsuite/tests/driver/mkdepend/T24384/E.hs - testsuite/tests/driver/mkdepend/dep-internal/DepInternal.hs → testsuite/tests/driver/mkdepend/T24384/dep-internal/DepInternal.hs - testsuite/tests/driver/mkdepend/dep-internal/dep-internal.pkg → testsuite/tests/driver/mkdepend/T24384/dep-internal/dep-internal.pkg - testsuite/tests/driver/mkdepend/dep-public/DepPublic.hs → testsuite/tests/driver/mkdepend/T24384/dep-public/DepPublic.hs - testsuite/tests/driver/mkdepend/dep-public/dep-public.pkg → testsuite/tests/driver/mkdepend/T24384/dep-public/dep-public.pkg - testsuite/tests/driver/mkdepend/dep/Dep.hs → testsuite/tests/driver/mkdepend/T24384/dep/Dep.hs - testsuite/tests/driver/mkdepend/dep/dep.pkg → testsuite/tests/driver/mkdepend/T24384/dep/dep.pkg - testsuite/tests/driver/mkdepend/foo.h → testsuite/tests/driver/mkdepend/T24384/foo.h - testsuite/tests/driver/mkdepend/lib/B.hs → testsuite/tests/driver/mkdepend/T24384/lib/B.hs - + testsuite/tests/driver/mkdepend/T24384/lib/B.hs-boot - testsuite/tests/driver/mkdepend/preproc.sh → testsuite/tests/driver/mkdepend/T24384/preproc.sh - testsuite/tests/driver/mkdepend/T24384a.stdout - + testsuite/tests/driver/mkdepend/T24384b.stdout - + testsuite/tests/driver/mkdepend/T24384c.stdout - testsuite/tests/driver/mkdepend/all.T - + testsuite/tests/driver/mkdepend/format_json.sh - + testsuite/tests/driver/mkdepend/format_makefile.sh - + testsuite/tests/driver/mkdepend/mhu01/a/A/Base.hs - + testsuite/tests/driver/mkdepend/mhu01/a/A/Base.hs-boot - + testsuite/tests/driver/mkdepend/mhu01/a/A/TH.hs - + testsuite/tests/driver/mkdepend/mhu01/a/Util.hs - + testsuite/tests/driver/mkdepend/mhu01/b/B/Normal.hs - + testsuite/tests/driver/mkdepend/mhu01/b/B/Splice.hs - + testsuite/tests/driver/mkdepend/mhu01/b/Util.hs - + testsuite/tests/driver/mkdepend/mhu01/c/C.hs - + testsuite/tests/driver/mkdepend/mhu01/unitA - + testsuite/tests/driver/mkdepend/mhu01/unitB - + testsuite/tests/driver/mkdepend/mhu01/unitC - + testsuite/tests/driver/mkdepend/mhu02/A.hs - + testsuite/tests/driver/mkdepend/mhu02/B.hs - + testsuite/tests/driver/mkdepend/mhu02/pp.sh - + testsuite/tests/driver/mkdepend/mhu02/unitA - + testsuite/tests/driver/mkdepend/mhu02/unitB - + testsuite/tests/driver/mkdepend/mhu03/pkg/A.hs - + testsuite/tests/driver/mkdepend/mhu03/pkg/pp.sh - + testsuite/tests/driver/mkdepend/mhu03/unitA - + testsuite/tests/driver/mkdepend/mkdepend01.dep-json - + testsuite/tests/driver/mkdepend/mkdepend01.dep-makefile - + testsuite/tests/driver/mkdepend/mkdepend01/A.hs - + testsuite/tests/driver/mkdepend/mkdepend_mhu01.dep-json - + testsuite/tests/driver/mkdepend/mkdepend_mhu01.dep-makefile - + testsuite/tests/driver/mkdepend/mkdepend_mhu02.dep-json - + testsuite/tests/driver/mkdepend/mkdepend_mhu03.dep-json - testsuite/tests/perf/compiler/large-project/all.T The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/8e8ce0393171e0fe2d381091d0ac81… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/8e8ce0393171e0fe2d381091d0ac81… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

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[Git][ghc/ghc][wip/fendor/dep-json] 4 commits: Add `-dep-json` flag to `ghc -M`
by Hannes Siebenhandl (＠fendor) 13 Oct '26

13 Oct '26

Hannes Siebenhandl pushed to branch wip/fendor/dep-json at Glasgow Haskell Compiler / GHC Commits: 1d8cbcfd by fendor at 2026-10-13T15:21:44+02:00 Add `-dep-json` flag to `ghc -M` Add an optional flag to `ghc -M` that allows to write the dependency information in JSON Lines format. The JSON Lines format enables us to stream the output of the dependency generation to a consumer. The output of `-dep-json` is streamed to a temporary file and then copied to the final destination to avoid partial writes. Each line contains one of two possible json objects: 1. A Home Unit Dependency * Contains the name of the home module, its unit, where it is located, whether a preprocessor is used, and all of its imports. Importantly, the imports include `-XExplicitLevelImports` information. * If requested via `-include-pkg-deps`, includes imports of external units, e.g. modules from `base`. * If requested via `-include-cpp-deps`, files included via CPP. 2. External Unit Dependency * Only if `-include-pkg-deps` is given * Contains unit-id, its package name and package id. - - - - - f493c74a by fendor at 2026-10-13T15:21:44+02:00 Add multiple home unit support to `ghc -M` Allows to process the module graph of multiple home units at once using the same syntax as `--make` and `--interactive`: ghc -M -unit @unitA -unit @unitB The semantics are identical to `--make` and `--interactive`. Each home unit can declare individually to use `-include-cpp-deps` and `-include-pkg-deps`. However, there can only be one output file, and `-dep-json` and `-dep-makefile` can only be provided at the top of the cli invocation. We introduce a new GHC API `doMkDepend` that allows to use multiple home units conveniently. The output of `-dep-json` and `-dep-makefile` does not change, since we were careful to choose a format that supports multiple home units from the start. Single home units are still accepted like before with no changes. - - - - - 4ae5d910 by fendor at 2026-10-13T15:21:44+02:00 Deprecate `doMkDependHS` in favour of `doMkDepend` - - - - - 8e8ce039 by fendor at 2026-10-13T15:21:44+02:00 Improve `ghc -M` test-suite Adds a more extensive test-suite for `ghc -M` mode. Introduce a dedicated test mode for running `ghc -M` tests more conveniently. Adds lots of normalizers that help to write `ghc -M` tests in a platform independent manner. Adds utility scripts that help format the output of `ghc -M`. - - - - - 61 changed files: - + changelog.d/make-depends-json - compiler/GHC/Driver/DynFlags.hs - compiler/GHC/Driver/MakeFile.hs - compiler/GHC/Driver/Session.hs - compiler/GHC/Driver/Session/Units.hs - compiler/GHC/Utils/Json.hs - + docs/users_guide/make-depends-json-schema-1_0.json - docs/users_guide/separate_compilation.rst - ghc/Main.hs - testsuite/driver/testglobals.py - testsuite/driver/testlib.py - testsuite/tests/driver/mkdepend/Makefile - + testsuite/tests/driver/mkdepend/README.md - testsuite/tests/driver/mkdepend/A.hs → testsuite/tests/driver/mkdepend/T24384/A.hs - testsuite/tests/driver/mkdepend/C.hs → testsuite/tests/driver/mkdepend/T24384/C.hs - testsuite/tests/driver/mkdepend/C.hs-boot → testsuite/tests/driver/mkdepend/T24384/C.hs-boot - testsuite/tests/driver/mkdepend/D.hs → testsuite/tests/driver/mkdepend/T24384/D.hs - testsuite/tests/driver/mkdepend/E.hs → testsuite/tests/driver/mkdepend/T24384/E.hs - testsuite/tests/driver/mkdepend/dep-internal/DepInternal.hs → testsuite/tests/driver/mkdepend/T24384/dep-internal/DepInternal.hs - testsuite/tests/driver/mkdepend/dep-internal/dep-internal.pkg → testsuite/tests/driver/mkdepend/T24384/dep-internal/dep-internal.pkg - testsuite/tests/driver/mkdepend/dep-public/DepPublic.hs → testsuite/tests/driver/mkdepend/T24384/dep-public/DepPublic.hs - testsuite/tests/driver/mkdepend/dep-public/dep-public.pkg → testsuite/tests/driver/mkdepend/T24384/dep-public/dep-public.pkg - testsuite/tests/driver/mkdepend/dep/Dep.hs → testsuite/tests/driver/mkdepend/T24384/dep/Dep.hs - testsuite/tests/driver/mkdepend/dep/dep.pkg → testsuite/tests/driver/mkdepend/T24384/dep/dep.pkg - testsuite/tests/driver/mkdepend/foo.h → testsuite/tests/driver/mkdepend/T24384/foo.h - testsuite/tests/driver/mkdepend/lib/B.hs → testsuite/tests/driver/mkdepend/T24384/lib/B.hs - + testsuite/tests/driver/mkdepend/T24384/lib/B.hs-boot - testsuite/tests/driver/mkdepend/preproc.sh → testsuite/tests/driver/mkdepend/T24384/preproc.sh - testsuite/tests/driver/mkdepend/T24384a.stdout - + testsuite/tests/driver/mkdepend/T24384b.stdout - + testsuite/tests/driver/mkdepend/T24384c.stdout - testsuite/tests/driver/mkdepend/all.T - + testsuite/tests/driver/mkdepend/format_json.sh - + testsuite/tests/driver/mkdepend/format_makefile.sh - + testsuite/tests/driver/mkdepend/mhu01/a/A/Base.hs - + testsuite/tests/driver/mkdepend/mhu01/a/A/Base.hs-boot - + testsuite/tests/driver/mkdepend/mhu01/a/A/TH.hs - + testsuite/tests/driver/mkdepend/mhu01/a/Util.hs - + testsuite/tests/driver/mkdepend/mhu01/b/B/Normal.hs - + testsuite/tests/driver/mkdepend/mhu01/b/B/Splice.hs - + testsuite/tests/driver/mkdepend/mhu01/b/Util.hs - + testsuite/tests/driver/mkdepend/mhu01/c/C.hs - + testsuite/tests/driver/mkdepend/mhu01/unitA - + testsuite/tests/driver/mkdepend/mhu01/unitB - + testsuite/tests/driver/mkdepend/mhu01/unitC - + testsuite/tests/driver/mkdepend/mhu02/A.hs - + testsuite/tests/driver/mkdepend/mhu02/B.hs - + testsuite/tests/driver/mkdepend/mhu02/pp.sh - + testsuite/tests/driver/mkdepend/mhu02/unitA - + testsuite/tests/driver/mkdepend/mhu02/unitB - + testsuite/tests/driver/mkdepend/mhu03/pkg/A.hs - + testsuite/tests/driver/mkdepend/mhu03/pkg/pp.sh - + testsuite/tests/driver/mkdepend/mhu03/unitA - + testsuite/tests/driver/mkdepend/mkdepend01.dep-json - + testsuite/tests/driver/mkdepend/mkdepend01.dep-makefile - + testsuite/tests/driver/mkdepend/mkdepend01/A.hs - + testsuite/tests/driver/mkdepend/mkdepend_mhu01.dep-json - + testsuite/tests/driver/mkdepend/mkdepend_mhu01.dep-makefile - + testsuite/tests/driver/mkdepend/mkdepend_mhu02.dep-json - + testsuite/tests/driver/mkdepend/mkdepend_mhu03.dep-json - testsuite/tests/perf/compiler/large-project/all.T The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/33ceb9a278d32aae2aecb48e2dbbac… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/33ceb9a278d32aae2aecb48e2dbbac… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

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[Git][ghc/ghc][wip/T27910] Improve exprOkForSpeculation
by Simon Peyton Jones (＠simonpj) 13 Oct '26

13 Oct '26

Simon Peyton Jones pushed to branch wip/T27910 at Glasgow Haskell Compiler / GHC Commits: 336b87e2 by Simon Peyton Jones at 2026-10-13T14:17:27+01:00 Improve exprOkForSpeculation Fixes #27910, which exposed an infelicity in exprOkForSpeculation The new story is carefully described in new Note [exprOkForSpeculation], esp (a-c) and (EOKS1). - - - - - 4 changed files: - compiler/GHC/Core/Utils.hs - + testsuite/tests/simplCore/should_compile/T27910.hs - + testsuite/tests/simplCore/should_compile/T27910.stderr - testsuite/tests/simplCore/should_compile/all.T Changes: ===================================== compiler/GHC/Core/Utils.hs ===================================== @@ -2260,7 +2260,8 @@ expr_ok fun_ok primop_ok other_expr app_ok :: (Id -> Bool) -> (PrimOp -> Bool) -> Id -> [CoreArg] -> Bool app_ok fun_ok primop_ok fun args | not (fun_ok fun) - = False -- This code path is only taken for Note [Speculative evaluation] + = False -- This code path is only taken for exprOkForSpecEval + -- See Note [Speculative evaluation] | idArity fun > n_val_args -- Partial application: just check passing the arguments is OK @@ -2323,30 +2324,35 @@ app_ok fun_ok primop_ok fun args where fun_ty = idType fun n_val_args = valArgCount args - (arg_tys, _) = splitPiTys fun_ty + (arg_tys, _) = splitPiTys fun_ty -- arg_tys are /uninstantiated/ + -- See (EOKS1) -- Even if a function call itself is OK, any unlifted -- args are still evaluated eagerly and must be checked + -- arg_ok bndr arg = field_ok bndr NotMarkedStrict arg + -- See Note [exprOkForSpeculation] (a-c) args_ok = all2Prefix arg_ok arg_tys args arg_ok :: PiTyVarBinder -> CoreExpr -> Bool - arg_ok (Named _) _ = True -- A type argument - arg_ok (Anon ty _) arg -- A term argument - | definitelyLiftedType (scaledThing ty) - = True -- lifted args are not evaluated eagerly - | otherwise - = expr_ok fun_ok primop_ok arg + arg_ok (Named _) _ = True + arg_ok (Anon ty _) arg = exprIsCheap arg || definitelyLiftedType (scaledThing ty) -- Used for strict DataCon worker arguments -- See (SFC1) of Note [Strict fields in Core] + -- See Note [exprOkForSpeculation] (a-c) fields_ok str_marks = all3Prefix field_ok arg_tys str_marks args field_ok :: PiTyVarBinder -> StrictnessMark -> CoreExpr -> Bool field_ok (Named _) _ _ = True field_ok (Anon ty _) str arg - | NotMarkedStrict <- str -- iff it's a lazy field - , definitelyLiftedType (scaledThing ty) -- and its type is lifted - = True -- then the worker app does not eval - | otherwise - = expr_ok fun_ok primop_ok arg + = case typeLevity_maybe (scaledThing ty) of + Just Lifted -> str == NotMarkedStrict + Just Unlifted -> exprIsCheap arg + Nothing -> exprIsCheap arg && str == NotMarkedStrict + -- The Nothing case happens for + -- (#,#) @rep1 @rep2 @ty1 @ty2 arg1 arg2 + -- We don't /instantiate/ the type (though we could) so we don't know + -- if lifted or not, so we conservatively check both conditions. This + -- gives a conservative answer False for (# null xs, null ys #), but + -- these unboxed tuples are usually ANF'd so it doesn't reallly matter. ----------------------------- altsAreExhaustive :: [Alt b] -> Bool @@ -2390,8 +2396,41 @@ cantEtaReduceFun fun -- Don't undersaturate StrictWorkerIds. -- See Note [CBV Function Ids: overview] in GHC.Types.Id.Info. -{- Note [exprOkForSpeculation and type classes] -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +{- Note [exprOkForSpeculation] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +Suppose we have + data T a = K !a Int# a + +Is the call (K e1 e2 e3) ok-for-speculation? Lok at the arguments e1..e3, +and their types. The call is ok-for-speculation if each argument satisfies +`field_ok`, namely: + (a) Arg type is definitely lifted => arg is not marked strict + (b) Arg type is definitely unlifted => (exprIsCheap arg) is True + (c) Otherwise => not marked strict && exprIsCheap + +For (a), an arbitrary /lazy/ argument is ok provided we don't have a bang. +For a strict argument you might wonder if we could use exprIsHNF, but see +Note [exprOkForSpeculation and evaluated variables]. So for strict arguments +we just say "no". + +For (b) a variable, or casted variable is fine. But not a call, say (f x). +Hence `exprisCheap`. + +For (c) we don't know if we are in case (a) or (b) so we conservatively 'and' +them. See (EOKS1) for how we can get this situation. + +(EOKS1) To get the lifted-ness or otherwise of the arguments we just look at the + /uninstantiated/ type of the data constructor or primop. We'd get better information + if we instantiated, but it's also more expensive. Example: + (#,#) :: forall r1 r2 (a::TYPE r1) (b::TYPE r2). a -> b -> (# a, b #) + If we have a call + (#,#) @LiftedRep @IntRep @Int @Int# 3 4# + then we could see accurate liftedness by instantiation, but we don't try. + Typically the argument is a variable, in which case `exprIsCheap` does a good job. + + +Note [exprOkForSpeculation and type classes] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Consider (#22745, #15205) \(d :: C a b). case eq_sel (sc_sel d) of ===================================== testsuite/tests/simplCore/should_compile/T27910.hs ===================================== @@ -0,0 +1,17 @@ +{-# LANGUAGE UnboxedTuples, MagicHash #-} +module T27910 where +import GHC.Exts + +k1 :: (# Int, Bool #) -> (# Int, Bool #) -> Int +{-# NOINLINE k1 #-} +k1 _ _ = 3 + +k2 :: (# Int#, Int# #) -> (# Int#, Int# #) -> Int +{-# NOINLINE k2 #-} +k2 _ _ = 3 + +lifted :: Int -> Bool -> Int +lifted x y = case (# x, y #) of r -> k1 r r + +unlifted :: Int# -> Int# -> Int +unlifted x y = case (# x, y #) of r -> k2 r r ===================================== testsuite/tests/simplCore/should_compile/T27910.stderr ===================================== @@ -0,0 +1,49 @@ + +==================== FloatOut stats: ==================== +2 Lets floated to top level; 0 Lets floated elsewhere; from 4 Lambda groups + + + +==================== FloatOut stats: ==================== +4 Lets floated to top level; 0 Lets floated elsewhere; from 6 Lambda groups + + + +==================== Grand total simplifier statistics ==================== +Total ticks: 30 + +8 PreInlineUnconditionally + 1 ds + 1 ds + 1 ds + 1 ds + 1 ds + 1 ds + 1 ds + 1 ds +2 PostInlineUnconditionally + 1 r + 1 r +4 UnfoldingDone + 2 GHC.Internal.Prim.void# + 1 T27910.k1 + 1 T27910.k2 +8 BetaReduction + 1 ds + 1 ds + 1 ds + 1 ds + 1 ds + 1 ds + 1 ds + 1 ds +4 KnownBranch + 2 wild + 1 ww + 1 ww +4 CaseElim + 2 ww + 2 ww +9 SimplifierDone 9 + + ===================================== testsuite/tests/simplCore/should_compile/all.T ===================================== @@ -627,3 +627,5 @@ test('T27749', compile, ['-O -g3 -ddump-simpl -dsuppress-uniques']) test('T27629', only_ways(['optasm']), makefile_test, ['T27629']) +test('T27910', grep_errmsg(r'KnownBranch'), compile, ['-O -dno-typeable-binds -ddump-simpl-stats -dsuppress-uniques']) + View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/336b87e20e8df777c38eab5361ffc4c… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/336b87e20e8df777c38eab5361ffc4c… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

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[Git][ghc/ghc][wip/T27724] More wibbles
by Simon Peyton Jones (＠simonpj) 13 Oct '26

13 Oct '26

Simon Peyton Jones pushed to branch wip/T27724 at Glasgow Haskell Compiler / GHC Commits: 9cb0b3e3 by Simon Peyton Jones at 2026-10-13T12:08:17+01:00 More wibbles - - - - - 5 changed files: - compiler/GHC/Builtin/WiredIn/Ids.hs - compiler/GHC/Core/Opt/Simplify/Iteration.hs - compiler/GHC/CoreToStg/Prep.hs - libraries/ghc-internal/src/GHC/Internal/Exts.hs - libraries/ghc-internal/src/GHC/Internal/Magic.hs Changes: ===================================== compiler/GHC/Builtin/WiredIn/Ids.hs ===================================== @@ -247,17 +247,19 @@ seqId = pcRepPolyId seqName ty concs info -- see Note [seqId magic] -- seq :: forall (r :: RuntimeRep) a (b :: TYPE r). a -> b -> b + -- NB: Uses a=alphaTyVar, b=rrPolyTyVar2 + -- Can't use rrPolyTyVar1 because that is called 'a' too. Sigh. ty = - mkInfForAllTy runtimeRep1TyVar - $ mkSpecForAllTys [alphaTyVar, rrPolyTyVar1] - $ mkVisFunTyMany alphaTy (mkVisFunTyMany rrPolyTy1 rrPolyTy1) + mkInfForAllTy runtimeRep2TyVar + $ mkSpecForAllTys [alphaTyVar, rrPolyTyVar2] + $ mkVisFunTyMany alphaTy (mkVisFunTyMany rrPolyTy2 rrPolyTy2) - [x,y] = mkTemplateLocals [alphaTy, rrPolyTy1] - rhs = mkLams ([runtimeRep1TyVar, alphaTyVar, rrPolyTyVar1, x, y]) $ - Case (Var x) x rrPolyTy1 [Alt DEFAULT [] (Var y)] + [x,y] = mkTemplateLocals [alphaTy, rrPolyTy2] + rhs = mkLams ([runtimeRep2TyVar, alphaTyVar, rrPolyTyVar2, x, y]) $ + Case (Var x) x rrPolyTy2 [Alt DEFAULT [] (Var y)] concs = mkRepPolyIdConcreteTyVars - [ ((rrPolyTy1, mkArgPos 1 Top), runtimeRep1TyVar)] + [ ((rrPolyTy2, mkArgPos 2 Top), runtimeRep2TyVar)] arity = 2 ===================================== compiler/GHC/Core/Opt/Simplify/Iteration.hs ===================================== @@ -1228,18 +1228,8 @@ simplExprF1 env (App fun arg) cont = do { cont' <- pushAppCont env fun arg cont ; simplExprF env fun cont' } simplExprF1 env (Cast body co) cont - = do { co1 <- {-#SCC "simplCast-simplCoercion" #-} - simplCoercion env co - - ; cont1 <- {-#SCC "simplCast-addCoerce" #-} - if isReflCo co1 - then return cont -- See Note [Optimising reflexivity] - else pushCast env co1 cont - -- True <=> co1 is optimised - - ; {-#SCC "simplCast-simplExprF" #-} - simplExprF env body cont1 } - + = do { cont1 <- pushInCast env co cont + ; simplExprF env body cont1 } simplExprF1 env expr@(Lam {}) cont = {-#SCC "simplExprF1-Lam" #-} @@ -1710,7 +1700,7 @@ on each successive composition -- that's at least quadratic. So: unfolding (seInlineDepth > 0), then instead of /optimising/ it again, just /substitute/ which is cheaper. See `simplCoercion`. -* In `pushCast` if we combine this new coercion with an existing one, +* In `pushOutCast` if we combine this new coercion with an existing one, we build a CastIt for (co1 ; co2) with sc_opt=False. * When unpacking a CastIt, in `rebuild`, we optimise the (presumably @@ -1724,7 +1714,7 @@ on each successive composition -- that's at least quadratic. So: Note [The sc_cast field of ApplyToVal] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -In the `ApplyToVal` case of `pushCast` we want to push an `OutCoercion` into the +In the `ApplyToVal` case of `pushOutCast` we want to push an `OutCoercion` into the argument. But the argument may or may not have been simplified (see Note [StaticEnv]) so we definitely can't just wrap the cast around the argument. Instead we store it in the `sc_cast` field -- this is the whole reason for the `sc_cast` field. @@ -1755,14 +1745,25 @@ addCastMCo (MCo co) cont = CastIt { sc_co = co, sc_opt = False, sc_cont = cont } pushCastMCo :: SimplEnv -> MOutCoercion -> SimplCont -> SimplM SimplCont pushCastMCo _env MRefl cont = return cont -pushCastMCo env (MCo co) cont = pushCast env co cont +pushCastMCo env (MCo co) cont = pushOutCast env co cont + +pushInCast :: SimplEnv -> InCoercion -> SimplCont -> SimplM SimplCont +pushInCast env co cont + = do { co1 <- {-#SCC "simplCast-simplCoercion" #-} + simplCoercion env co + + ; if isReflCo co1 + then return cont -- See Note [Optimising reflexivity] + else {-#SCC "simplCast-addCoerce" #-} + pushOutCast env co1 cont + } -pushCast :: SimplEnv -> OutCoercion -> SimplCont -> SimplM SimplCont -pushCast env co cont +pushOutCast :: SimplEnv -> OutCoercion -> SimplCont -> SimplM SimplCont +pushOutCast env co cont = go co True cont where - -- ToDo: pushCast Refl (ApplylToVal arg1 (ApplyToVal arg2 ...)) + -- ToDo: pushOutCast Refl (ApplylToVal arg1 (ApplyToVal arg2 ...)) -- will do lots of unnecessary work. go :: OutCoercion -> Bool -> SimplCont -> SimplM SimplCont go co1 _ (CastIt { sc_co = co2, sc_cont = cont }) -- See Note [Optimising reflexivity] @@ -2294,7 +2295,7 @@ simplOutExpr env expr cont | Cast e co <- expr -- The inlined expression may be (x |> co) -- and the cast may cancel with `cont` - = do { cont' <- pushCast env co cont + = do { cont' <- pushOutCast env co cont ; simplOutExpr env e cont' } | (Var v, args) <- collectArgs expr @@ -2384,7 +2385,7 @@ simplOutId env noinline_fun cont = do { -- Push any arguments in `the_call` onto `encl_app_cont` let push_args :: InExpr -> SimplCont -> SimplM (InExpr, SimplCont) -- push_args just pushes multiple arguments onto the continuation - push_args (Cast f co) cont = do { cont' <- pushCast arg_se co cont + push_args (Cast f co) cont = do { cont' <- pushInCast arg_se co cont ; push_args f cont' } push_args (App f a) cont = do { cont' <- pushAppCont arg_se f a cont ; push_args f cont' } ===================================== compiler/GHC/CoreToStg/Prep.hs ===================================== @@ -1265,28 +1265,37 @@ isLazyExpr (Var f `App` _ `App` _) = f `hasKey` lazyIdKey isLazyExpr _ = False eliminateMagicCall :: Id -> [ArgInfo] -> Maybe (CoreExpr, [ArgInfo]) -eliminateMagicCall f (AIApp Type{} : AIApp arg : args) - | f `hasKey` lazyIdKey = Just (arg,args) - -- Replace (lazy a) with a, and - -- See Note [lazyId magic] in GHC.Types.Id.Make - | f `hasKey` nospecIdKey = Just (arg,args) - -- Replace (nospec a) with a - -- See Note [nospecId magic] in GHC.Types.Id.Make - -eliminateMagicCall f (AIApp Type{} : AIApp (Type arg_ty) : rest_args) +eliminateMagicCall f all_args + -- Replace (lazy a) with a, and + -- See Note [lazyId magic] in GHC.Types.Id.Make + | f `hasKey` lazyIdKey + , AIApp Type{} : AIApp arg : args <- all_args + = Just (arg,args) + + -- Replace (nospec a) with a + -- See Note [nospecId magic] in GHC.Types.Id.Make + | f `hasKey` nospecIdKey + , AIApp Type{} : AIApp arg : args <- all_args + = Just (arg,args) + + -- Replace (noinline a) with a + -- See Note [noinlineId magic] in GHC.Types.Id.Make | isNoinlineId f - = case rest_args of - (AIApp arg : args) -> Just (arg, args) - -- Replace (noinline a) with a - -- See Note [noinlineId magic] in GHC.Types.Id.Make - - _ -> Just (Lam x (Var x), rest_args) - -- Unsaturated (noinline @rep @ty) generates a lambda - where - x = mkTemplateLocal 0 arg_ty + = case all_args of + AIApp Type{} : AIApp (Type {}) : AIApp arg : args + -> -- noinline @rep @ty e --> e + Just (arg,args) -- Applied to a value argument + + AIApp Type{} : AIApp (Type arg_ty) : args + -> -- noinline @rep @ty --> \(x:ty).x + Just (Lam x (Var x), args) -- Type args only, make a lambda + where + x = mkTemplateLocal 0 arg_ty + _ -> pprPanic "Un-applied noinline" (ppr all_args) -eliminateMagicCall _ _ = Nothing + | otherwise + = Nothing {- Note [runRW magic] ~~~~~~~~~~~~~~~~~~~~~ ===================================== libraries/ghc-internal/src/GHC/Internal/Exts.hs ===================================== @@ -1,6 +1,7 @@ {-# LANGUAGE FlexibleInstances #-} {-# LANGUAGE MagicHash #-} {-# LANGUAGE MultiParamTypeClasses #-} +{-# LANGUAGE ScopedTypeVariables #-} {-# LANGUAGE NoImplicitPrelude #-} {-# LANGUAGE TypeFamilies #-} {-# LANGUAGE UnboxedTuples #-} @@ -336,6 +337,12 @@ import GHC.Internal.Unsafe.Coerce ( unsafeCoerce# ) -- just for re-export import GHC.Internal.Tuple (maxTupleSize) import GHC.Internal.Box (Box) +{- ********************************************************************** +* * +* Some list functions +* * +********************************************************************** -} + -- | 'the' ensures that all the elements of the list are identical -- and then returns that unique element the :: Eq a => [a] -> a @@ -369,8 +376,11 @@ groupByFB c n eq xs0 = groupByFBCore xs0 where (ys, zs) = span (eq x) xs --- ----------------------------------------------------------------------------- --- tracing +{- ********************************************************************** +* * +* Tracing +* * +********************************************************************** -} traceEvent :: String -> IO () traceEvent = GHC.Internal.Debug.Trace.traceEventIO @@ -398,6 +408,11 @@ data SpecConstrAnnotation = NoSpecConstr | ForceSpecConstr ) +{- ********************************************************************** +* * +* Mutable variables and arrays +* * +********************************************************************** -} -- | An implementation of the old @atomicModifyMutVar#@ primop in -- terms of the new 'atomicModifyMutVar2#' primop, for backwards ===================================== libraries/ghc-internal/src/GHC/Internal/Magic.hs ===================================== @@ -1,6 +1,7 @@ {-# LANGUAGE Trustworthy #-} {-# LANGUAGE NoImplicitPrelude #-} {-# LANGUAGE MagicHash #-} +{-# LANGUAGE EmptyCase #-} {-# LANGUAGE DataKinds #-} {-# LANGUAGE PolyKinds #-} {-# LANGUAGE ScopedTypeVariables #-} @@ -40,6 +41,13 @@ module GHC.Internal.Magic ( inline, noinline, lazy, oneShot, runRW#, DataToTag(. import GHC.Internal.Prim (State#, realWorld#, RealWorld, Int#) import GHC.Internal.Types +{- ********************************************************************** +* * +* inline and noinline + +* * +********************************************************************** -} + -- | The call @inline f@ arranges that @f@ is inlined, regardless of -- its size. More precisely, the call @inline f@ rewrites to the -- right-hand side of @f@'s definition. This allows the programmer to @@ -73,10 +81,18 @@ noinline :: forall (r :: RuntimeRep) (a :: TYPE r). a -> a {-# NOINLINE noinline #-} -- See Note [noinlineId magic] in GHC.Builtin.WiredIn.Ids -noinline = noinline -- Never called, eliminated in CorePrep - -- We can't conveniently call `error` here because - -- GHC.Internal.Err depends on GHC.Internal.Magic.noinline! - -- Hence this silly loop. +noinline = case () of {} + -- `noinline` should never be called -- it is eliminated in CorePrep + -- We can't conveniently call 'error' here, so we sneakly use an empty case + -- case () of {} + -- which expands to a call to GHC.Internal.Control.Exception.Base.patError + + +{- ********************************************************************** +* * +* lazy +* * +********************************************************************** -} -- | The 'lazy' function restrains strictness analysis a little. The -- call @lazy e@ means the same as @e@, but 'lazy' has a magical @@ -104,6 +120,12 @@ lazy x = x -- Result: happiness +{- ********************************************************************** +* * +* oneShot +* * +********************************************************************** -} + -- | The 'oneShot' function can be used to give a hint to the compiler that its -- argument will be called at most once, which may (or may not) enable certain -- optimizations. It can be useful to improve the performance of code in continuation @@ -122,6 +144,13 @@ oneShot f = f -- Implementation note: This is wired in in GHC.Types.Id.Make, so the code here is -- mostly there to have a place for the documentation. + +{- ********************************************************************** +* * +* runRW# +* * +********************************************************************** -} + -- | Apply a function to a @'State#' 'RealWorld'@ token. When manually applying -- a function to `realWorld#`, it is necessary to use @NOINLINE@ to prevent -- semantically undesirable floating. `runRW#` is inlined, but only very late @@ -136,6 +165,13 @@ runRW# :: forall (r :: RuntimeRep) (o :: TYPE r). {-# NOINLINE runRW# #-} -- runRW# is inlined manually in CorePrep runRW# m = m realWorld# + +{- ********************************************************************** +* * +* DataToTag and dataToTag# +* * +********************************************************************** -} + -- | @'dataToTag#'@ evaluates its argument and returns the index -- (starting at zero) of the constructor used to produce that -- argument. Any algebraic data type with all of its constructors @@ -154,6 +190,13 @@ type DataToTag :: forall {lev :: Levity}. TYPE (BoxedRep lev) -> Constraint class DataToTag a where dataToTag# :: a -> Int# + +{- ********************************************************************** +* * +* considerAccessible +* * +********************************************************************** -} + -- | Semantically, @considerAccessible = True@. But it has special meaning -- to the pattern-match checker, which will never flag the clause in which -- 'considerAccessible' occurs as a guard as redundant or inaccessible. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/9cb0b3e3648a3e644a8780e111e1277… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/9cb0b3e3648a3e644a8780e111e1277… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

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[Git][ghc/ghc][wip/fendor/dep-json] 4 commits: Add `-dep-json` flag to `ghc -M`
by Hannes Siebenhandl (＠fendor) 13 Oct '26

13 Oct '26

Hannes Siebenhandl pushed to branch wip/fendor/dep-json at Glasgow Haskell Compiler / GHC Commits: 85253c32 by fendor at 2026-10-13T15:04:32+02:00 Add `-dep-json` flag to `ghc -M` Add an optional flag to `ghc -M` that allows to write the dependency information in JSON Lines format. The JSON Lines format enables us to stream the output of the dependency generation to a consumer. The output of `-dep-json` is streamed to a temporary file and then copied to the final destination to avoid partial writes. Each line contains one of two possible json objects: 1. A Home Unit Dependency * Contains the name of the home module, its unit, where it is located, whether a preprocessor is used, and all of its imports. Importantly, the imports include `-XExplicitLevelImports` information. * If requested via `-include-pkg-deps`, includes imports of external units, e.g. modules from `base`. * If requested via `-include-cpp-deps`, files included via CPP. 2. External Unit Dependency * Only if `-include-pkg-deps` is given * Contains unit-id, its package name and package id. - - - - - f0d48b5c by fendor at 2026-10-13T15:04:32+02:00 Add multiple home unit support to `ghc -M` Allows to process the module graph of multiple home units at once using the same syntax as `--make` and `--interactive`: ghc -M -unit @unitA -unit @unitB The semantics are identical to `--make` and `--interactive`. Each home unit can declare individually to use `-include-cpp-deps` and `-include-pkg-deps`. However, there can only be one output file, and `-dep-json` and `-dep-makefile` can only be provided at the top of the cli invocation. We introduce a new GHC API `doMkDepend` that allows to use multiple home units conveniently. The output of `-dep-json` and `-dep-makefile` does not change, since we were careful to choose a format that supports multiple home units from the start. Single home units are still accepted like before with no changes. - - - - - 445e76c2 by fendor at 2026-10-13T15:04:32+02:00 Deprecate `doMkDependHS` in favour of `doMkDepend` - - - - - 33ceb9a2 by fendor at 2026-10-13T15:04:32+02:00 Improve `ghc -M` test-suite Adds a more extensive test-suite for `ghc -M` mode. Introduce a dedicated test mode for running `ghc -M` tests more conveniently. Adds lots of normalizers that help to write `ghc -M` tests in a platform independent manner. Adds utility scripts that help format the output of `ghc -M`. - - - - - 61 changed files: - + changelog.d/make-depends-json - compiler/GHC/Driver/DynFlags.hs - compiler/GHC/Driver/MakeFile.hs - compiler/GHC/Driver/Session.hs - compiler/GHC/Driver/Session/Units.hs - compiler/GHC/Utils/Json.hs - + docs/users_guide/make-depends-json-schema-1_0.json - docs/users_guide/separate_compilation.rst - ghc/Main.hs - testsuite/driver/testglobals.py - testsuite/driver/testlib.py - testsuite/tests/driver/mkdepend/Makefile - + testsuite/tests/driver/mkdepend/README.md - testsuite/tests/driver/mkdepend/A.hs → testsuite/tests/driver/mkdepend/T24384/A.hs - testsuite/tests/driver/mkdepend/C.hs → testsuite/tests/driver/mkdepend/T24384/C.hs - testsuite/tests/driver/mkdepend/C.hs-boot → testsuite/tests/driver/mkdepend/T24384/C.hs-boot - testsuite/tests/driver/mkdepend/D.hs → testsuite/tests/driver/mkdepend/T24384/D.hs - testsuite/tests/driver/mkdepend/E.hs → testsuite/tests/driver/mkdepend/T24384/E.hs - testsuite/tests/driver/mkdepend/dep-internal/DepInternal.hs → testsuite/tests/driver/mkdepend/T24384/dep-internal/DepInternal.hs - testsuite/tests/driver/mkdepend/dep-internal/dep-internal.pkg → testsuite/tests/driver/mkdepend/T24384/dep-internal/dep-internal.pkg - testsuite/tests/driver/mkdepend/dep-public/DepPublic.hs → testsuite/tests/driver/mkdepend/T24384/dep-public/DepPublic.hs - testsuite/tests/driver/mkdepend/dep-public/dep-public.pkg → testsuite/tests/driver/mkdepend/T24384/dep-public/dep-public.pkg - testsuite/tests/driver/mkdepend/dep/Dep.hs → testsuite/tests/driver/mkdepend/T24384/dep/Dep.hs - testsuite/tests/driver/mkdepend/dep/dep.pkg → testsuite/tests/driver/mkdepend/T24384/dep/dep.pkg - testsuite/tests/driver/mkdepend/foo.h → testsuite/tests/driver/mkdepend/T24384/foo.h - testsuite/tests/driver/mkdepend/lib/B.hs → testsuite/tests/driver/mkdepend/T24384/lib/B.hs - + testsuite/tests/driver/mkdepend/T24384/lib/B.hs-boot - testsuite/tests/driver/mkdepend/preproc.sh → testsuite/tests/driver/mkdepend/T24384/preproc.sh - testsuite/tests/driver/mkdepend/T24384a.stdout - + testsuite/tests/driver/mkdepend/T24384b.stdout - + testsuite/tests/driver/mkdepend/T24384c.stdout - testsuite/tests/driver/mkdepend/all.T - + testsuite/tests/driver/mkdepend/format_json.sh - + testsuite/tests/driver/mkdepend/format_makefile.sh - + testsuite/tests/driver/mkdepend/mhu01/a/A/Base.hs - + testsuite/tests/driver/mkdepend/mhu01/a/A/Base.hs-boot - + testsuite/tests/driver/mkdepend/mhu01/a/A/TH.hs - + testsuite/tests/driver/mkdepend/mhu01/a/Util.hs - + testsuite/tests/driver/mkdepend/mhu01/b/B/Normal.hs - + testsuite/tests/driver/mkdepend/mhu01/b/B/Splice.hs - + testsuite/tests/driver/mkdepend/mhu01/b/Util.hs - + testsuite/tests/driver/mkdepend/mhu01/c/C.hs - + testsuite/tests/driver/mkdepend/mhu01/unitA - + testsuite/tests/driver/mkdepend/mhu01/unitB - + testsuite/tests/driver/mkdepend/mhu01/unitC - + testsuite/tests/driver/mkdepend/mhu02/A.hs - + testsuite/tests/driver/mkdepend/mhu02/B.hs - + testsuite/tests/driver/mkdepend/mhu02/pp.sh - + testsuite/tests/driver/mkdepend/mhu02/unitA - + testsuite/tests/driver/mkdepend/mhu02/unitB - + testsuite/tests/driver/mkdepend/mhu03/pkg/A.hs - + testsuite/tests/driver/mkdepend/mhu03/pkg/pp.sh - + testsuite/tests/driver/mkdepend/mhu03/unitA - + testsuite/tests/driver/mkdepend/mkdepend01.dep-json - + testsuite/tests/driver/mkdepend/mkdepend01.dep-makefile - + testsuite/tests/driver/mkdepend/mkdepend01/A.hs - + testsuite/tests/driver/mkdepend/mkdepend_mhu01.dep-json - + testsuite/tests/driver/mkdepend/mkdepend_mhu01.dep-makefile - + testsuite/tests/driver/mkdepend/mkdepend_mhu02.dep-json - + testsuite/tests/driver/mkdepend/mkdepend_mhu03.dep-json - testsuite/tests/perf/compiler/large-project/all.T The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/8b48865561b8434280512fcdd0b5e1… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/8b48865561b8434280512fcdd0b5e1… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

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[Git][ghc/ghc][wip/fendor/dep-json] 5 commits: Refactor Makefile to use phases appropriately
by Hannes Siebenhandl (＠fendor) 13 Oct '26

13 Oct '26

Hannes Siebenhandl pushed to branch wip/fendor/dep-json at Glasgow Haskell Compiler / GHC Commits: c1d92abf by fendor at 2026-10-13T14:44:03+02:00 Refactor Makefile to use phases appropriately Process the dependency information independently of the Makefile generation. Introduces intermediate data types that contain all the relevant information instead of ad-hoc generation of output lines. - - - - - 2e58dfe6 by fendor at 2026-10-13T14:44:03+02:00 Add `-dep-json` flag to `ghc -M` Add an optional flag to `ghc -M` that allows to write the dependency information in JSON Lines format. The JSON Lines format enables us to stream the output of the dependency generation to a consumer. The output of `-dep-json` is streamed to a temporary file and then copied to the final destination to avoid partial writes. Each line contains one of two possible json objects: 1. A Home Unit Dependency * Contains the name of the home module, its unit, where it is located, whether a preprocessor is used, and all of its imports. Importantly, the imports include `-XExplicitLevelImports` information. * If requested via `-include-pkg-deps`, includes imports of external units, e.g. modules from `base`. * If requested via `-include-cpp-deps`, files included via CPP. 2. External Unit Dependency * Only if `-include-pkg-deps` is given * Contains unit-id, its package name and package id. - - - - - 821aeee7 by fendor at 2026-10-13T14:57:30+02:00 Add multiple home unit support to `ghc -M` Allows to process the module graph of multiple home units at once using the same syntax as `--make` and `--interactive`: ghc -M -unit @unitA -unit @unitB The semantics are identical to `--make` and `--interactive`. Each home unit can declare individually to use `-include-cpp-deps` and `-include-pkg-deps`. However, there can only be one output file, and `-dep-json` and `-dep-makefile` can only be provided at the top of the cli invocation. We introduce a new GHC API `doMkDepend` that allows to use multiple home units conveniently. The output of `-dep-json` and `-dep-makefile` does not change, since we were careful to choose a format that supports multiple home units from the start. Single home units are still accepted like before with no changes. - - - - - fc47edd6 by fendor at 2026-10-13T14:57:33+02:00 Deprecate `doMkDependHS` in favour of `doMkDepend` - - - - - 8b488655 by fendor at 2026-10-13T14:58:07+02:00 Improve `ghc -M` test-suite Adds a more extensive test-suite for `ghc -M` mode. Introduce a dedicated test mode for running `ghc -M` tests more conveniently. Adds lots of normalizers that help to write `ghc -M` tests in a platform independent manner. Adds utility scripts that help format the output of `ghc -M`. - - - - - 61 changed files: - + changelog.d/make-depends-json - compiler/GHC/Driver/DynFlags.hs - compiler/GHC/Driver/MakeFile.hs - compiler/GHC/Driver/Session.hs - compiler/GHC/Driver/Session/Units.hs - compiler/GHC/Utils/Json.hs - + docs/users_guide/make-depends-json-schema-1_0.json - docs/users_guide/separate_compilation.rst - ghc/Main.hs - testsuite/driver/testglobals.py - testsuite/driver/testlib.py - + testsuite/tests/driver/mkdepend/Makefile - + testsuite/tests/driver/mkdepend/README.md - + testsuite/tests/driver/mkdepend/T24384/A.hs - + testsuite/tests/driver/mkdepend/T24384/C.hs - + testsuite/tests/driver/mkdepend/T24384/C.hs-boot - + testsuite/tests/driver/mkdepend/T24384/D.hs - + testsuite/tests/driver/mkdepend/T24384/E.hs - + testsuite/tests/driver/mkdepend/T24384/dep-internal/DepInternal.hs - + testsuite/tests/driver/mkdepend/T24384/dep-internal/dep-internal.pkg - + testsuite/tests/driver/mkdepend/T24384/dep-public/DepPublic.hs - + testsuite/tests/driver/mkdepend/T24384/dep-public/dep-public.pkg - + testsuite/tests/driver/mkdepend/T24384/dep/Dep.hs - + testsuite/tests/driver/mkdepend/T24384/dep/dep.pkg - + testsuite/tests/driver/mkdepend/T24384/foo.h - + testsuite/tests/driver/mkdepend/T24384/lib/B.hs - + testsuite/tests/driver/mkdepend/T24384/lib/B.hs-boot - + testsuite/tests/driver/mkdepend/T24384/preproc.sh - + testsuite/tests/driver/mkdepend/T24384a.stdout - + testsuite/tests/driver/mkdepend/T24384b.stdout - + testsuite/tests/driver/mkdepend/T24384c.stdout - + testsuite/tests/driver/mkdepend/all.T - + testsuite/tests/driver/mkdepend/format_json.sh - + testsuite/tests/driver/mkdepend/format_makefile.sh - + testsuite/tests/driver/mkdepend/mhu01/a/A/Base.hs - + testsuite/tests/driver/mkdepend/mhu01/a/A/Base.hs-boot - + testsuite/tests/driver/mkdepend/mhu01/a/A/TH.hs - + testsuite/tests/driver/mkdepend/mhu01/a/Util.hs - + testsuite/tests/driver/mkdepend/mhu01/b/B/Normal.hs - + testsuite/tests/driver/mkdepend/mhu01/b/B/Splice.hs - + testsuite/tests/driver/mkdepend/mhu01/b/Util.hs - + testsuite/tests/driver/mkdepend/mhu01/c/C.hs - + testsuite/tests/driver/mkdepend/mhu01/unitA - + testsuite/tests/driver/mkdepend/mhu01/unitB - + testsuite/tests/driver/mkdepend/mhu01/unitC - + testsuite/tests/driver/mkdepend/mhu02/A.hs - + testsuite/tests/driver/mkdepend/mhu02/B.hs - + testsuite/tests/driver/mkdepend/mhu02/pp.sh - + testsuite/tests/driver/mkdepend/mhu02/unitA - + testsuite/tests/driver/mkdepend/mhu02/unitB - + testsuite/tests/driver/mkdepend/mhu03/pkg/A.hs - + testsuite/tests/driver/mkdepend/mhu03/pkg/pp.sh - + testsuite/tests/driver/mkdepend/mhu03/unitA - + testsuite/tests/driver/mkdepend/mkdepend01.dep-json - + testsuite/tests/driver/mkdepend/mkdepend01.dep-makefile - + testsuite/tests/driver/mkdepend/mkdepend01/A.hs - + testsuite/tests/driver/mkdepend/mkdepend_mhu01.dep-json - + testsuite/tests/driver/mkdepend/mkdepend_mhu01.dep-makefile - + testsuite/tests/driver/mkdepend/mkdepend_mhu02.dep-json - + testsuite/tests/driver/mkdepend/mkdepend_mhu03.dep-json - testsuite/tests/perf/compiler/large-project/all.T The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/30bb9f48bdb58947f18a8132ebb0ac… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/30bb9f48bdb58947f18a8132ebb0ac… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

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