[Git][ghc/ghc][wip/romes/ast-ohne-faststring] ttg: Using Text over FastString in the AST
by Rodrigo Mesquita (＠alt-romes) 01 Jul '26
by Rodrigo Mesquita (＠alt-romes) 01 Jul '26
01 Jul '26
Rodrigo Mesquita pushed to branch wip/romes/ast-ohne-faststring at Glasgow Haskell Compiler / GHC
Commits:
428bc7ab by Rodrigo Mesquita at 2026-07-01T18:51:11+01:00
ttg: Using Text over FastString in the AST
To make the AST independent of GHC, this commit replaces usages of
`FastString` with `HText` in the AST, killing the last edge from
Language.Haskell.* to GHC.* modules.
Even though we /do/ want to use FastStrings in general -- critically in
Names or Ids -- there is no particular reason for the FastStrings that
occur in the AST proper to be FastStrings. Strings in the AST are
typically unique and don't benefit particularly from being interned
FastStrings with Uniques for fast comparison.
`HText` is a newtype string wrapper around `Text` which uses GHC's
Modified UTF-8 encoding exclusively. It is an opaque type, to ensure it
is only modified and converted in ways which preserve the Modified UTF-8
encoding in a way that roundtrips (as opposed to losing information,
which would happen if using bare `Text`).
Modified UTF-8 must be used to represent the Haskell AST because the
Haskell Report allows surrogate code points. `Text` operations use UTF-8
proper and replaces surrogates with a placeholder value, thus is
unsuitable for the AST directly. See the `Language.Haskell.Syntax.Text`
module header for more details.
Final progress towards #21592
Closes #21628
- - - - -
93 changed files:
- compiler/GHC/Builtin/Utils.hs
- compiler/GHC/Cmm/CLabel.hs
- compiler/GHC/Core/Ppr.hs
- compiler/GHC/Core/TyCon.hs
- compiler/GHC/Data/FastString.hs
- compiler/GHC/Data/StringBuffer.hs
- compiler/GHC/Driver/Errors/Ppr.hs
- compiler/GHC/Driver/Session.hs
- compiler/GHC/Hs/Decls.hs
- compiler/GHC/Hs/Expr.hs
- compiler/GHC/Hs/Lit.hs
- compiler/GHC/Hs/Type.hs
- compiler/GHC/Hs/Utils.hs
- compiler/GHC/HsToCore.hs
- compiler/GHC/HsToCore/Errors/Types.hs
- compiler/GHC/HsToCore/Expr.hs
- compiler/GHC/HsToCore/Foreign/C.hs
- compiler/GHC/HsToCore/Foreign/JavaScript.hs
- compiler/GHC/HsToCore/Foreign/Wasm.hs
- compiler/GHC/HsToCore/Match.hs
- compiler/GHC/HsToCore/Match/Literal.hs
- compiler/GHC/HsToCore/Pmc/Desugar.hs
- compiler/GHC/HsToCore/Pmc/Solver/Types.hs
- compiler/GHC/HsToCore/Quote.hs
- compiler/GHC/Iface/Syntax.hs
- compiler/GHC/Parser.y
- compiler/GHC/Parser/Errors/Ppr.hs
- compiler/GHC/Parser/Errors/Types.hs
- compiler/GHC/Parser/HaddockLex.x
- compiler/GHC/Parser/Lexer.x
- compiler/GHC/Parser/PostProcess.hs
- compiler/GHC/Rename/Bind.hs
- compiler/GHC/Rename/Env.hs
- compiler/GHC/Rename/HsType.hs
- compiler/GHC/Rename/Module.hs
- compiler/GHC/Rename/Splice.hs
- compiler/GHC/Rename/Utils.hs
- compiler/GHC/StgToByteCode.hs
- compiler/GHC/StgToCmm/Foreign.hs
- compiler/GHC/StgToCmm/Prim.hs
- compiler/GHC/StgToJS/FFI.hs
- compiler/GHC/Tc/Deriv/Generate.hs
- compiler/GHC/Tc/Deriv/Generics.hs
- compiler/GHC/Tc/Errors.hs
- compiler/GHC/Tc/Errors/Ppr.hs
- compiler/GHC/Tc/Gen/Bind.hs
- compiler/GHC/Tc/Gen/Expr.hs
- compiler/GHC/Tc/Gen/HsType.hs
- compiler/GHC/Tc/Gen/Pat.hs
- compiler/GHC/Tc/Gen/Sig.hs
- compiler/GHC/Tc/Gen/Splice.hs
- compiler/GHC/Tc/Instance/Class.hs
- compiler/GHC/Tc/Solver/Dict.hs
- compiler/GHC/Tc/TyCl.hs
- compiler/GHC/Tc/TyCl/Utils.hs
- compiler/GHC/Tc/Types/Origin.hs
- compiler/GHC/Tc/Validity.hs
- compiler/GHC/ThToHs.hs
- compiler/GHC/Types/Basic.hs
- compiler/GHC/Types/Error.hs
- compiler/GHC/Types/FieldLabel.hs
- compiler/GHC/Types/ForeignCall.hs
- compiler/GHC/Types/Literal.hs
- compiler/GHC/Unit/Module/Warnings.hs
- compiler/GHC/Utils/Binary.hs
- compiler/GHC/Utils/Outputable.hs
- compiler/Language/Haskell/Syntax/Basic.hs
- compiler/Language/Haskell/Syntax/Decls.hs
- compiler/Language/Haskell/Syntax/Decls/Foreign.hs
- compiler/Language/Haskell/Syntax/Expr.hs
- compiler/Language/Haskell/Syntax/Lit.hs
- compiler/Language/Haskell/Syntax/Module/Name.hs
- + compiler/Language/Haskell/Syntax/Text.hs
- compiler/Language/Haskell/Syntax/Type.hs
- compiler/ghc.cabal.in
- testsuite/tests/count-deps/CountDepsAst.stdout
- testsuite/tests/count-deps/CountDepsParser.stdout
- testsuite/tests/parser/should_compile/DumpParsedAst.stderr
- testsuite/tests/parser/should_compile/DumpParsedAstComments.stderr
- testsuite/tests/parser/should_compile/DumpRenamedAst.stderr
- testsuite/tests/parser/should_compile/DumpTypecheckedAst.stderr
- + testsuite/tests/parser/should_run/StringStartsWithNull.hs
- + testsuite/tests/parser/should_run/StringStartsWithNull.stdout
- testsuite/tests/parser/should_run/all.T
- testsuite/tests/perf/compiler/hard_hole_fits.stderr
- utils/check-exact/ExactPrint.hs
- utils/check-exact/check-exact.cabal
- utils/haddock/haddock-api/haddock-api.cabal
- utils/haddock/haddock-api/src/Haddock.hs
- utils/haddock/haddock-api/src/Haddock/Backends/Hyperlinker/Parser.hs
- utils/haddock/haddock-api/src/Haddock/Convert.hs
- utils/haddock/haddock-api/src/Haddock/Interface/Create.hs
- utils/haddock/haddock-api/src/Haddock/Interface/LexParseRn.hs
The diff was not included because it is too large.
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/428bc7ab6ba04214c6d15539ce66894…
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[Git][ghc/ghc][wip/jeltsch/textual-bytecode-output] Remove output of constructor and pointer tags
by Wolfgang Jeltsch (＠jeltsch) 01 Jul '26
by Wolfgang Jeltsch (＠jeltsch) 01 Jul '26
01 Jul '26
Wolfgang Jeltsch pushed to branch wip/jeltsch/textual-bytecode-output at Glasgow Haskell Compiler / GHC
Commits:
c5255641 by Wolfgang Jeltsch at 2026-07-01T20:49:51+03:00
Remove output of constructor and pointer tags
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1 changed file:
- compiler/GHC/ByteCode/Show.hs
Changes:
=====================================
compiler/GHC/ByteCode/Show.hs
=====================================
@@ -251,8 +251,6 @@ pprDataConstructorInfoTable dataConstrName ConInfoTable {..}
pprTablePositioning $ conItblTablesNextToCode,
pprPointerWordCount $ conItblPtrs,
pprNonPointerWordCount $ conItblNPtrs,
- pprConstructorTag $ conItblConTag,
- pprPointerTag $ conItblPtrTag,
pprDescription $ conItblDescr
]
@@ -268,14 +266,6 @@ pprPointerWordCount = entry (text "number of words for pointers:") . ppr
pprNonPointerWordCount :: Int -> SDoc
pprNonPointerWordCount = entry (text "number of words for non-pointers:") . ppr
--- | […]
-pprConstructorTag :: Int -> SDoc
-pprConstructorTag = entry (text "constructor tag:") . ppr
-
--- | […]
-pprPointerTag :: Int -> SDoc
-pprPointerTag = entry (text "pointer tag:") . ppr
-
-- | […]
pprDescription :: ByteString -> SDoc
pprDescription = entry (text "description:") .
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/c52556410a83f5515ad0425b4ed1cb9…
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[Git][ghc/ghc][wip/fix-26971] 2 commits: Decoupling 'L.H.S' from 'GHC.Hs.Doc'
by recursion-ninja (＠recursion-ninja) 01 Jul '26
by recursion-ninja (＠recursion-ninja) 01 Jul '26
01 Jul '26
recursion-ninja pushed to branch wip/fix-26971 at Glasgow Haskell Compiler / GHC
Commits:
f64cb654 by Recursion Ninja at 2026-07-01T09:10:45-04:00
Decoupling 'L.H.S' from 'GHC.Hs.Doc'
* Migrated 'GHC.Hs.Doc' and 'GHC.Hs.DocString' AST defintions from 'GHC.*' namespace,
to new 'Language.Haskell.Syntax.Doc' module in the 'L.H.S' "namespace."
* Updated 'HsDocString to be TTG-parameterised as 'HsDocString pass'.
* Added 'GHC.Hs.Extension.Pass': splits 'GhcPass'/'Pass' and all 'HsDocString'
TTG instances out of 'GHC.Hs.Extension', which re-exports it unchanged
(this is backwards compatible and prevents the introduction of a boot file).
* Deleted 'GHC.Hs.Doc.hs-boot'; removed all 'L.H.S.*' imports of 'GHC.Hs.Doc'.
* Updated 'GHC.Hs.DocString' to be TTG pass-parameterised throughout; moved
'mkHsDocStringChunk'/'unpackHDSC' here (require 'GHC.Utils.Encoding').
* Split 'GHC.Rename.Doc.rnHsDoc' from 'rnHsDocIdentifiersOnly'.
* Updated parser, renamer, typechecker, HIE, and exact-print for new types.
* Added 'HsDocString' TTG instances for 'DocNameI' to 'Haddock.Types'.
Resolves #26971
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688c7e4b by Recursion Ninja at 2026-07-01T13:24:57-04:00
Module split 'GHC.Hs.Lit' to avoid boot file build issues:
* Removes the {-# SOURCE #-} GHC.Hs.Expr (pprExpr) import from 'GHC.Hs.Lit'
* Removes direct 'Language.Haskell.Syntax.Expr (HsExpr)' usage from 'GHC.Hs.Lit'
* Moves "overloaded" literal declarations and instances into 'GHC.Hs.Lit.Overloaded'
* Moves "qualified" literal declarations and instances into 'GHC.Hs.Lit.Qualified'
* Moves "type-checked" literal declarations and instances into 'GHC.Hs.Lit.Typechecked'
* Moves shared normal-literal helpers into 'GHC.Hs.Lit.Internal'
* Maintains 'GHC.Hs.Lit' backwards compatibility by importing and re-exporting the moved API
* Leaves boot files untouched (alternative being more boot file definitions)
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40 changed files:
- compiler/GHC/Builtin/Utils.hs
- compiler/GHC/Hs.hs
- compiler/GHC/Hs/Doc.hs
- − compiler/GHC/Hs/Doc.hs-boot
- compiler/GHC/Hs/DocString.hs
- compiler/GHC/Hs/Extension.hs
- + compiler/GHC/Hs/Extension/Pass.hs
- compiler/GHC/Hs/ImpExp.hs
- compiler/GHC/Hs/Lit.hs
- + compiler/GHC/Hs/Lit/Internal.hs
- + compiler/GHC/Hs/Lit/Overloaded.hs
- + compiler/GHC/Hs/Lit/Qualified.hs
- + compiler/GHC/Hs/Lit/Typechecked.hs
- compiler/GHC/HsToCore/Docs.hs
- compiler/GHC/Iface/Ext/Ast.hs
- compiler/GHC/Iface/Syntax.hs
- compiler/GHC/Parser/Annotation.hs
- compiler/GHC/Parser/HaddockLex.x
- compiler/GHC/Parser/Lexer.x
- compiler/GHC/Parser/PostProcess/Haddock.hs
- compiler/GHC/Rename/Doc.hs
- compiler/GHC/Rename/Module.hs
- compiler/GHC/Tc/Errors/Hole.hs
- compiler/GHC/Tc/Errors/Hole/FitTypes.hs
- compiler/GHC/Tc/Gen/Splice.hs
- compiler/GHC/Tc/Module.hs
- compiler/GHC/Types/Hint.hs
- compiler/Language/Haskell/Syntax.hs
- compiler/Language/Haskell/Syntax/Decls.hs
- + compiler/Language/Haskell/Syntax/Doc.hs
- compiler/Language/Haskell/Syntax/Extension.hs
- compiler/Language/Haskell/Syntax/ImpExp.hs
- compiler/Language/Haskell/Syntax/Type.hs
- compiler/ghc.cabal.in
- utils/check-exact/ExactPrint.hs
- utils/check-exact/Utils.hs
- utils/haddock/haddock-api/src/Haddock/Interface/Create.hs
- utils/haddock/haddock-api/src/Haddock/Interface/LexParseRn.hs
- utils/haddock/haddock-api/src/Haddock/Interface/Rename.hs
- utils/haddock/haddock-api/src/Haddock/Types.hs
The diff was not included because it is too large.
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/eb9f93e6cfb364808872755f05b26b…
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[Git][ghc/ghc][wip/marge_bot_batch_merge_job] 35 commits: gitlab-ci: Drop vestigial references to make build system
by Marge Bot (＠marge-bot) 01 Jul '26
by Marge Bot (＠marge-bot) 01 Jul '26
01 Jul '26
Marge Bot pushed to branch wip/marge_bot_batch_merge_job at Glasgow Haskell Compiler / GHC
Commits:
701088db by Ben Gamari at 2026-07-01T10:34:03-04:00
gitlab-ci: Drop vestigial references to make build system
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62d54a53 by Ben Gamari at 2026-07-01T10:34:03-04:00
gitlab-ci: Add support for running specifying a job's testsuite ways
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7f97ac2c by Ben Gamari at 2026-07-01T10:34:03-04:00
gitlab-ci: Run llvm testsuite ways in llvm jobs
Addresses #25762.
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7ea75116 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Add normalise_ddump_deriv setup function
Some tests check the result of -ddump-deriv, which may contain INLINE pragmas depending on optimization flags.
With normalise_ddump_deriv setup function, INLINE pragmas are stripped off.
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c7a8199f by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Use -dsuppress-idinfo to make tests more robust
Previously, T18052a and T21755 were failing on 'optasm' and 'optllvm' ways because of visibility of unfoldings.
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a12122e5 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Use a trick to keep large objects alive
Previously, T17574 and T19381 were failing on 'optasm' and 'optllvm' ways because of compiler optimizations.
Change them to use NOINLINE to prevent unwanted optimizations.
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1a95b327 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Only run T24224 in 'normal' way
This test is a frontend-only one and breaks if optimizations are enabled.
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8abea737 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Ignore T18118's stderr
When optimizations are enabled, the compiler emits a warning (You cannot SPECIALISE ...).
The message is not important, so ignore it.
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9453a722 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Mark T816 and tc216 broken with optimizations
These tests are about type checking, so we should not care too much if they are broken with optimizations.
See #26952
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0aef9ec0 by Ben Gamari at 2026-07-01T10:34:03-04:00
testsuite: ds014 is not longer broken
It now appears to pass in the ways it was marked as broken in.
Closes #14901.
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4692d1e4 by Ben Gamari at 2026-07-01T10:34:03-04:00
testsuite: Only run stack cloning tests in the normal way
These are too dependent upon code generation specifics to pass in most
other ways.
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c154df26 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Update options_ghc_fbyte-code
The `-fbyte-code` option used to be overriden by `-fllvm` but it is no longer true since !14872 was merged.
I updated the test to accept the new behavior.
Closes #27049
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5d8bb7b5 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Only run T22744 in 'normal' way
This test takes a long time on optimized ways.
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d1e74c8e by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Disable tests that use -finfo-table-map on llvm ways
Currently, -finfo-table-map does not work with -fllvm. See #26435
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3bf38c84 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Don't run T24726 on optimized ways
If optimizations are enabled, the rewrite rule just fires and -drule-check will report nothing.
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e4eef116 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Use -fno-unoptimized-core-for-interpreter when running LinkableUsage01/02
Optimizations for the bytecode interpreter are considered experimental, and need a flag to be enabled.
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234a9872 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Suppress unwanted optimizations on T25284
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99a2af2f by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Don't run stack_big_ret with optimizations
Stack layout may change with optimizations enabled.
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04c836df by ARATA Mizuki at 2026-07-01T10:34:04-04:00
testsuite: Mark memo001 broken on optimized ways
See #27396
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1a8a24f4 by ARATA Mizuki at 2026-07-01T10:34:04-04:00
testsuite: Mark syn-perf broken on optimized ways
See #27398
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40412093 by Duncan Coutts at 2026-07-01T10:34:50-04:00
Add a test for thread scheduler fairness
It also tests that the interval timer and context switching works.
We also test that fairness is lost when the context switching interval
is too coarse for the duration of the test.
We add this test before doing surgery on the interval timer, so we have
decent coverage.
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3f34d557 by Duncan Coutts at 2026-07-01T10:34:50-04:00
Make exported stop/startTimer no-ops, and rename internal functions
Specifically, internally rename:
stop/startTimer to pause/unpauseTimer
stop/startTicker to pause/unpauseTicker
and keep stop/startTimer as exported functions, but now as no-ops.
In the past the stop/startTicker actions were used incorrectly as if
they were synchronous, which they are not. See issue #27105. We now
document pause/unpackTicker as being async and not to be used for the
purpose of concurrency safety.
The existing stop/startTimer (note Timer not Ticker, the Timer calls the
Ticker!) are also exported from the RTS as a public API. This was
historically because the ticker used signals and it was important to
suspend the timer signel over a process fork. So these functions were
exported to be used by the process and unix libraries.
We cannot just remove the RTS exports, but we now make them no-ops, and
they can be removed from the process and unix library later. This
was already documented in a changelog.d entry no-more-timer-signal but
due to changes during the MR process the change to make stop/startTicker
into no-ops didn't make it into the earlier MR.
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02e84e5f by Duncan Coutts at 2026-07-01T10:34:51-04:00
Make exitTicker/exitTimer unconditionally synchronous
We never use them asynchronously, and we should never need to do so.
And update some related comments.
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13db6a72 by Duncan Coutts at 2026-07-01T10:34:51-04:00
posix ticker: update and improve comments on (un)pause and exit
Clarify what is async vs sync.
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43d9a07d by Duncan Coutts at 2026-07-01T10:34:51-04:00
posix ticker: split out ppoll/select helper functions
Move the #ifdefs out of the main code body by introducing local helper
functions and types, which themselves have two implementations (with a
common API) based on ppoll or select.
This helps improve clarity/readability.
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a5491baa by Duncan Coutts at 2026-07-01T10:34:51-04:00
posix ticker: improve the implementation
The existing implementation supported pausing and exiting, with the
implementation of pausing reling on a mutex and condition variable.
It needed to check the pause and stop shared variables on every
iteration. It relies on ppoll or select, to wait on the timeout and also
wait on an interrupt fd. The interrupt fd was only used for prompt
exit/shutdown, and not for pausing or other notification. The pause only
needed a lock and a memory operation, but the pause was not prompt. The
resume used a lock, and signaling a cond var.
The new implementation uses a somewhat more regular design: every
notification is done by setting a shared variable and
interrupting/notifying the ticker via the fd. The ticker thread does not
need to check any shared variables on normal timer expiry, only when it
recevies notification. This may be a micro-optimisation, but the tick
occurs 100 times a second by default so any improvements in the hot path
are amplified. When the ticker thread does receive notification it can
check the various shared variables and update its local state. The
blocking relies on using ppoll/select but without a timeout. This avoids
the condition var and also allows further notifications when paused
(also used for unpausing).
This design can be extended with further notification types if needed by
using and checking further shared vars (or making existing shared vars
an enum or counter). This may be used in future for additional
notifications to the ticker thread. This will likely be used to proxy
wakeUpRts from a single handler context for example. And this approach,
avoiding mutexes, is compatible with use from signal handlers.
So overall, it's:
* slightly simpler / more regular;
* easier to extend with additional notifications;
* probably slightly more efficient (but a micro-optimisation);
* and supports calling notification from signal handlers
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5b20821e by Duncan Coutts at 2026-07-01T10:34:51-04:00
posix ticker: further minor local renaming for code clarity
Improve the clarity with better choice of names for several local vars
and function.
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1f3ec5e0 by Duncan Coutts at 2026-07-01T10:34:51-04:00
win32 ticker: split out local helper functions
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596e7307 by Duncan Coutts at 2026-07-01T10:34:51-04:00
win32 ticker: provide guarantee about concurrency and idempotency
Use a lock to ensure pause/unpause can be used concurrently. Use a
paused variable, protected by the lock, to ensure that pause and unpause
are both idempotent. This is what the portable API expects.
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1870edd7 by Duncan Coutts at 2026-07-01T10:34:51-04:00
win32 ticker: make the initial tick be after one wait interval
There is no need to tick immediately. This is consistent with the
posix implementation.
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7c15ab5b by Duncan Coutts at 2026-07-01T10:34:51-04:00
ticker: remove now-unnecessary layer of enable/disable
There was an atomic variable used to block *part* of the actions of the
tick handler. This still did not make stopTimer synchronous, even for
the part of the the handle_tick actions it covered. It also added a more
expensive (sequentuially consistent) atomic operation in the hot path
for the handle_tick action, whereas our new design requires no atomic
ops at all.
Now that we have eliminate the need for synchronous stop/startTicker,
we don't need this not-quite-working-anyway atomic protocol. The new
pause/unpauseTicker is explicitly asynchronous and idempotent.
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8585f8cb by Duncan Coutts at 2026-07-01T10:34:51-04:00
ticker: add TODOs about issue #27250: too much being done from handle_tick
The handle_tick should not perform I/O, block, perform long-running
operations or call arbitrary user code. Unfortunately, everything to
do with the eventlog (at the moment) falls into all those categories.
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ff501510 by fendor at 2026-07-01T13:12:06-04:00
Add 'backendInfoTableMapValidity' backend predicate
Check whether the backend supports the `-finfo-table-map` flag and
ignore it otherwise.
Improve by-design documentation of `backendCodeOutput`.
`Backend` is **abstract by design**. Make this clearer in
`backendCodeOutput` which is incorrectly being used as a proxy for
`Backend`.
Instead, define the desired property predicates in GHC.Driver.Backend
In the process, make `backendCodeOutput` total.
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9916f60f by fendor at 2026-07-01T13:12:06-04:00
Add failing test for `-finfo-table-map` and bytecode backend
If you compile a module using the bytecode backend, with
-finfo-table-map, then the info table map doesn't get populated for the
module.
This is because the -finfo-table-map code path is implemented mostly in
the StgToCmm phase which isn't run when creating bytecode.
Ticket #27039
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12d6eb4b by Alan Zimmerman at 2026-07-01T13:12:07-04:00
EPA: Remove LocatedLW from MatchGroup
This is the last usage of LocatedLW / SrcSpanAnnLW
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86 changed files:
- .gitlab/ci.sh
- .gitlab/generate-ci/gen_ci.hs
- .gitlab/jobs.yaml
- compiler/GHC/Driver/Backend.hs
- compiler/GHC/Driver/CodeOutput.hs
- compiler/GHC/Driver/Main/Compile.hs
- compiler/GHC/Driver/Pipeline.hs
- compiler/GHC/Driver/Session.hs
- compiler/GHC/Hs/Dump.hs
- compiler/GHC/Hs/Expr.hs
- compiler/GHC/Hs/Utils.hs
- compiler/GHC/Iface/Ext/Ast.hs
- compiler/GHC/Parser.y
- compiler/GHC/Parser/Annotation.hs
- compiler/GHC/Parser/PostProcess.hs
- compiler/GHC/Parser/Types.hs
- compiler/GHC/Rename/Bind.hs
- compiler/GHC/Rename/Utils.hs
- compiler/GHC/Tc/Gen/Arrow.hs
- compiler/GHC/Tc/Gen/Do.hs
- compiler/GHC/Tc/Gen/Expr.hs
- compiler/GHC/Tc/Gen/Match.hs
- compiler/GHC/Tc/TyCl/PatSyn.hs
- compiler/GHC/ThToHs.hs
- libraries/base/tests/all.T
- libraries/ghc-heap/tests/all.T
- rts/RtsStartup.c
- rts/Schedule.c
- rts/Ticker.h
- rts/Timer.c
- rts/Timer.h
- rts/include/rts/Timer.h
- rts/posix/Ticker.c
- rts/win32/Ticker.c
- testsuite/driver/testlib.py
- testsuite/tests/arityanal/should_compile/T21755.stderr
- testsuite/tests/arityanal/should_compile/all.T
- testsuite/tests/bytecode/TLinkable/all.T
- testsuite/tests/cmm/should_compile/all.T
- + testsuite/tests/concurrent/should_run/T27105.hs
- testsuite/tests/concurrent/should_run/all.T
- testsuite/tests/core-to-stg/T25284/Cls.hs
- testsuite/tests/deSugar/should_fail/all.T
- testsuite/tests/deSugar/should_run/all.T
- testsuite/tests/deriving/should_compile/all.T
- testsuite/tests/driver/options_ghc/Mod_fbyte_code.hs
- testsuite/tests/driver/options_ghc/all.T
- testsuite/tests/driver/options_ghc/options_ghc_fbyte-code.stderr
- testsuite/tests/generics/GenDerivOutput.hs
- testsuite/tests/generics/GenDerivOutput1_0.hs
- testsuite/tests/generics/GenDerivOutput1_1.hs
- testsuite/tests/generics/T10604/T10604_deriving.hs
- testsuite/tests/generics/T10604/all.T
- testsuite/tests/generics/all.T
- testsuite/tests/ghc-api/exactprint/T22919.stderr
- testsuite/tests/ghc-api/exactprint/ZeroWidthSemi.stderr
- testsuite/tests/ghci/scripts/all.T
- + testsuite/tests/ghci/scripts/bytecodeIPE.hs
- + testsuite/tests/ghci/scripts/bytecodeIPE.script
- + testsuite/tests/ghci/scripts/bytecodeIPE.stderr
- + testsuite/tests/ghci/scripts/bytecodeIPE.stdout
- testsuite/tests/module/mod185.stderr
- testsuite/tests/parser/should_compile/DumpParsedAst.stderr
- testsuite/tests/parser/should_compile/DumpParsedAstComments.stderr
- testsuite/tests/parser/should_compile/DumpRenamedAst.stderr
- testsuite/tests/parser/should_compile/DumpSemis.stderr
- testsuite/tests/parser/should_compile/DumpTypecheckedAst.stderr
- testsuite/tests/parser/should_compile/KindSigs.stderr
- testsuite/tests/parser/should_compile/T15279.stderr
- testsuite/tests/parser/should_compile/T20718.stderr
- testsuite/tests/parser/should_compile/T20846.stderr
- testsuite/tests/parser/should_compile/all.T
- testsuite/tests/perf/compiler/all.T
- testsuite/tests/printer/T18052a.stderr
- testsuite/tests/printer/Test20297.stdout
- testsuite/tests/printer/Test24533.stdout
- testsuite/tests/printer/all.T
- testsuite/tests/profiling/perf/T23103/all.T
- testsuite/tests/profiling/should_run/all.T
- testsuite/tests/rts/T17574.hs
- testsuite/tests/rts/T19381.hs
- testsuite/tests/rts/all.T
- testsuite/tests/rts/ipe/T24005/all.T
- testsuite/tests/simplCore/should_compile/all.T
- testsuite/tests/typecheck/should_compile/all.T
- utils/check-exact/ExactPrint.hs
The diff was not included because it is too large.
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/c17d42efbab2a26f2843044cfde968…
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01 Jul '26
Magnus pushed new branch wip/mangoiv/retry-fetching at Glasgow Haskell Compiler / GHC
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[Git][ghc/ghc][wip/sjakobi/lazy-field-anns] Add -XLazyFieldAnnotations (GHC proposal 752)
by Simon Jakobi (＠sjakobi2) 01 Jul '26
by Simon Jakobi (＠sjakobi2) 01 Jul '26
01 Jul '26
Simon Jakobi pushed to branch wip/sjakobi/lazy-field-anns at Glasgow Haskell Compiler / GHC
Commits:
001e8576 by Simon Jakobi at 2026-07-01T17:10:08+02:00
Add -XLazyFieldAnnotations (GHC proposal 752)
Unbundle the prefix `~` lazy field annotation syntax from StrictData. The
new LazyFieldAnnotations extension controls whether `~` is accepted on
constructor fields. StrictData (and Strict, transitively) imply the new
extension.
See https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0752-l….
Closes #24455.
Assisted-by: Claude Opus 4.8
- - - - -
18 changed files:
- + changelog.d/lazy-field-annotations
- compiler/GHC/Driver/Flags.hs
- compiler/GHC/Tc/Errors/Ppr.hs
- compiler/GHC/Tc/Errors/Types.hs
- compiler/GHC/Tc/TyCl.hs
- docs/users_guide/exts/strict.rst
- libraries/ghc-internal/src/GHC/Internal/LanguageExtensions.hs
- + testsuite/tests/deSugar/should_run/LazyFieldAnnotationsSemantics.hs
- + testsuite/tests/deSugar/should_run/LazyFieldAnnotationsSemantics.stdout
- testsuite/tests/deSugar/should_run/all.T
- testsuite/tests/driver/T4437.hs
- testsuite/tests/interface-stability/template-haskell-exports.stdout
- + testsuite/tests/typecheck/should_compile/LazyFieldAnnotations.hs
- testsuite/tests/typecheck/should_compile/all.T
- testsuite/tests/typecheck/should_fail/LazyFieldsDisabled.stderr
- + testsuite/tests/typecheck/should_fail/LazyFieldsDisabledStrictData.hs
- + testsuite/tests/typecheck/should_fail/LazyFieldsDisabledStrictData.stderr
- testsuite/tests/typecheck/should_fail/all.T
Changes:
=====================================
changelog.d/lazy-field-annotations
=====================================
@@ -0,0 +1,14 @@
+section: language
+synopsis: Add the `LazyFieldAnnotations` extension
+issues: #24455
+mrs: !16246
+
+description: {
+ The new :extension:`LazyFieldAnnotations` extension permits the prefix
+ ``~`` lazy field annotation on data and GADT constructor fields without
+ enabling :extension:`StrictData`. :extension:`StrictData` (and therefore
+ :extension:`Strict`) now implies :extension:`LazyFieldAnnotations` and
+ continues to control the default strictness of unannotated fields.
+
+ See `GHC Proposal #752 <https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0752-l…>`_.
+}
=====================================
compiler/GHC/Driver/Flags.hs
=====================================
@@ -261,6 +261,7 @@ extensionName = \case
LangExt.ExplicitLevelImports -> "ExplicitLevelImports"
LangExt.ImplicitStagePersistence -> "ImplicitStagePersistence"
LangExt.QualifiedStrings -> "QualifiedStrings"
+ LangExt.LazyFieldAnnotations -> "LazyFieldAnnotations"
-- | Is this extension known by any other names? For example
-- -XGeneralizedNewtypeDeriving is accepted
@@ -343,6 +344,7 @@ impliedXFlags
, (LangExt.TemplateHaskell, On LangExt.TemplateHaskellQuotes)
, (LangExt.Strict, On LangExt.StrictData)
+ , (LangExt.StrictData, On LangExt.LazyFieldAnnotations)
-- Historically only UnboxedTuples was required for unboxed sums to work.
-- To avoid breaking code, we make UnboxedTuples imply UnboxedSums.
=====================================
compiler/GHC/Tc/Errors/Ppr.hs
=====================================
@@ -3231,7 +3231,7 @@ instance Diagnostic TcRnMessage where
TcRnHasFieldResolvedIncomplete{}
-> noHints
TcRnBadFieldAnnotation _ _ LazyFieldsDisabled
- -> [suggestExtension LangExt.StrictData]
+ -> [suggestExtension LangExt.LazyFieldAnnotations]
TcRnBadFieldAnnotation{}
-> noHints
TcRnSuperclassCycle{}
=====================================
compiler/GHC/Tc/Errors/Types.hs
=====================================
@@ -6355,7 +6355,7 @@ data PatSynInvalidRhsReason
data BadFieldAnnotationReason where
{-| A lazy data type field annotation (~) was used without enabling the
- extension StrictData.
+ extension LazyFieldAnnotations.
Test cases:
LazyFieldsDisabled
=====================================
compiler/GHC/Tc/TyCl.hs
=====================================
@@ -5186,7 +5186,7 @@ checkValidDataCon dflags existential_ok tc con
; let check_bang :: Type -> HsSrcBang -> HsImplBang -> Int -> TcM ()
check_bang orig_arg_ty bang rep_bang n
| HsSrcBang _ _ SrcLazy <- bang
- , not (bang_opt_strict_data bang_opts)
+ , not (xopt LangExt.LazyFieldAnnotations dflags)
= addErrTc (bad_bang n LazyFieldsDisabled)
-- Warn about UNPACK without "!"
=====================================
docs/users_guide/exts/strict.rst
=====================================
@@ -155,6 +155,45 @@ Note the following points:
for more discussion and examples.
+.. _lazy-field-annotations:
+
+Lazy field annotations
+----------------------
+
+.. extension:: LazyFieldAnnotations
+ :shortdesc: Allow the prefix ``~`` lazy field annotation on constructor fields.
+
+ :since: 10.2.1
+
+ Allow the prefix ``~`` lazy field annotation on data and GADT constructor
+ fields.
+
+``LazyFieldAnnotations`` allows a prefix ``~`` lazy annotation in every
+constructor-field position where a prefix ``!`` strict annotation is accepted:
+Haskell-98 prefix and record fields, and GADT argument types and record
+fields. ::
+
+ {-# LANGUAGE LazyFieldAnnotations #-}
+
+ data A = A ~Int Bool
+ data B = B { b1 :: ~Int, b2 :: !Bool }
+
+ data C where
+ C1 :: ~Int -> C
+ C2 :: { c1 :: ~Int, c2 :: !Bool } -> C
+
+A field annotated with ``~`` is lazy: it is not forced when the constructor is
+built, but held as a thunk — the same behaviour as an unannotated field under
+:extension:`NoStrictData`.
+
+The ``~`` annotation must be written in prefix form::
+
+ data T = MkT ~Int -- valid
+ data T = MkT ~ Int -- invalid
+
+See `GHC Proposal #229 <https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0229-w…>`__
+for the precise rules.
+
.. _strict-data:
Strict-by-default data types
@@ -163,6 +202,8 @@ Strict-by-default data types
.. extension:: StrictData
:shortdesc: Treat datatype fields as strict by default.
+ :implies: :extension:`LazyFieldAnnotations`
+
:since: 8.0.1
Make fields of data types defined in the current module strict by default.
@@ -183,13 +224,8 @@ we interpret it as if they had written ::
The extension only affects definitions in this module.
-The ``~`` annotation must be written in prefix form::
-
- data T = MkT ~Int -- valid
- data T = MkT ~ Int -- invalid
-
-See `GHC Proposal #229 <https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0229-w…>`__
-for the precise rules.
+The ``~`` lazy field annotation is provided by :extension:`LazyFieldAnnotations`
+(which ``StrictData`` implies); see :ref:`lazy-field-annotations`.
.. _strict:
=====================================
libraries/ghc-internal/src/GHC/Internal/LanguageExtensions.hs
=====================================
@@ -169,6 +169,7 @@ data Extension
| ExplicitLevelImports
| ImplicitStagePersistence
| QualifiedStrings
+ | LazyFieldAnnotations
deriving (Eq, Enum, Show, Generic, Bounded)
-- 'Ord' and 'Bounded' are provided for GHC API users (see discussions
-- in https://gitlab.haskell.org/ghc/ghc/merge_requests/2707 and
=====================================
testsuite/tests/deSugar/should_run/LazyFieldAnnotationsSemantics.hs
=====================================
@@ -0,0 +1,24 @@
+{-# LANGUAGE LazyFieldAnnotations #-}
+
+-- | LazyFieldAnnotations does not change the default strictness of fields.
+-- Without StrictData an unannotated field stays lazy and a ~ field is lazy
+-- too; a ! field is still strict.
+module Main where
+
+import Control.Exception (try, evaluate, SomeException)
+
+data T = Plain Int -- unannotated: lazy
+ | Lazy ~Int -- explicit ~: lazy
+ | Strict !Int -- explicit !: strict
+
+-- | Does building the constructor force the field?
+forcesField :: T -> IO Bool
+forcesField x = do
+ r <- try (evaluate x) :: IO (Either SomeException T)
+ pure (either (const True) (const False) r)
+
+main :: IO ()
+main = do
+ print =<< forcesField (Plain undefined) -- False: lazy
+ print =<< forcesField (Lazy undefined) -- False: lazy
+ print =<< forcesField (Strict undefined) -- True: strict
=====================================
testsuite/tests/deSugar/should_run/LazyFieldAnnotationsSemantics.stdout
=====================================
@@ -0,0 +1,3 @@
+False
+False
+True
=====================================
testsuite/tests/deSugar/should_run/all.T
=====================================
@@ -76,3 +76,5 @@ test('T19680A', normal, compile_and_run, [''])
test('T20024', exit_code(1), compile_and_run, [''])
test('Or5', exit_code(1), compile_and_run, [''])
+
+test('LazyFieldAnnotationsSemantics', normal, compile_and_run, [''])
=====================================
testsuite/tests/driver/T4437.hs
=====================================
@@ -36,7 +36,7 @@ check title expected got
-- See Note [Adding a language extension] in compiler/GHC/Driver/Session.hs.
expectedGhcOnlyExtensions :: [String]
-expectedGhcOnlyExtensions = [ "QualifiedStrings", "Modifiers" ]
+expectedGhcOnlyExtensions = [ "QualifiedStrings", "Modifiers", "LazyFieldAnnotations" ]
expectedCabalOnlyExtensions :: [String]
expectedCabalOnlyExtensions = ["Generics",
=====================================
testsuite/tests/interface-stability/template-haskell-exports.stdout
=====================================
@@ -269,6 +269,7 @@ module Language.Haskell.TH where
| ExplicitLevelImports
| ImplicitStagePersistence
| QualifiedStrings
+ | LazyFieldAnnotations
type FamilyResultSig :: *
data FamilyResultSig = NoSig | KindSig Kind | TyVarSig (TyVarBndr ())
type FamilyResultSigQ :: *
@@ -880,6 +881,7 @@ module Language.Haskell.TH.LanguageExtensions where
| ExplicitLevelImports
| ImplicitStagePersistence
| QualifiedStrings
+ | LazyFieldAnnotations
module Language.Haskell.TH.Lib where
-- Safety: Safe
@@ -1625,6 +1627,7 @@ module Language.Haskell.TH.Syntax where
| ExplicitLevelImports
| ImplicitStagePersistence
| QualifiedStrings
+ | LazyFieldAnnotations
type FamilyResultSig :: *
data FamilyResultSig = NoSig | KindSig Kind | TyVarSig (TyVarBndr ())
type FieldExp :: *
=====================================
testsuite/tests/typecheck/should_compile/LazyFieldAnnotations.hs
=====================================
@@ -0,0 +1,15 @@
+{-# LANGUAGE LazyFieldAnnotations #-}
+{-# LANGUAGE GADTs #-}
+
+-- | LazyFieldAnnotations accepts the prefix ~ annotation in every
+-- constructor-field position.
+module LazyFieldAnnotations where
+
+-- Haskell-98 prefix and record fields
+data A = A ~Int Bool
+data B = B { b1 :: ~Int, b2 :: !Bool }
+
+-- GADT argument types and record fields
+data C where
+ C1 :: ~Int -> C
+ C2 :: { c1 :: ~Int, c2 :: !Bool } -> C
=====================================
testsuite/tests/typecheck/should_compile/all.T
=====================================
@@ -967,4 +967,5 @@ test('T26805a', normal, compile, [''])
test('T24464', normal, compile, [''])
test('ExpansionQLIm', normal, compile, [''])
test('T23135', normal, compile, [''])
+test('LazyFieldAnnotations', normal, compile, [''])
=====================================
testsuite/tests/typecheck/should_fail/LazyFieldsDisabled.stderr
=====================================
@@ -1,8 +1,8 @@
-
LazyFieldsDisabled.hs:3:10: error: [GHC-81601]
• Lazy field annotations (~) are disabled
on the first argument of ‘A’
• In the definition of data constructor ‘A’
In the data type declaration for ‘A’
Suggested fix:
- Perhaps you intended to use the ‘StrictData’ extension (implied by ‘Strict’)
+ Perhaps you intended to use the ‘LazyFieldAnnotations’ extension (implied by ‘StrictData’)
+
=====================================
testsuite/tests/typecheck/should_fail/LazyFieldsDisabledStrictData.hs
=====================================
@@ -0,0 +1,8 @@
+{-# LANGUAGE StrictData #-}
+{-# LANGUAGE NoLazyFieldAnnotations #-}
+
+-- | A later NoLazyFieldAnnotations overrides the implication from StrictData,
+-- so ~ is rejected.
+module LazyFieldsDisabledStrictData where
+
+data A = A ~Int
=====================================
testsuite/tests/typecheck/should_fail/LazyFieldsDisabledStrictData.stderr
=====================================
@@ -0,0 +1,8 @@
+LazyFieldsDisabledStrictData.hs:8:10: error: [GHC-81601]
+ • Lazy field annotations (~) are disabled
+ on the first argument of ‘A’
+ • In the definition of data constructor ‘A’
+ In the data type declaration for ‘A’
+ Suggested fix:
+ Perhaps you intended to use the ‘LazyFieldAnnotations’ extension (implied by ‘StrictData’)
+
=====================================
testsuite/tests/typecheck/should_fail/all.T
=====================================
@@ -690,6 +690,7 @@ test('T21444', normal, compile_fail, [''])
test('T23308', normal, compile_fail, [''])
test('MultiAssocDefaults', normal, compile_fail, [''])
test('LazyFieldsDisabled', normal, compile_fail, [''])
+test('LazyFieldsDisabledStrictData', normal, compile_fail, [''])
test('TyfamsDisabled', normal, compile_fail, [''])
test('CommonFieldResultTypeMismatch', normal, compile_fail, [''])
test('CommonFieldTypeMismatch', normal, compile_fail, [''])
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/001e8576db154b24ac6ee0e1acbb10f…
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[Git][ghc/ghc][master] 12 commits: Add a test for thread scheduler fairness
by Marge Bot (＠marge-bot) 01 Jul '26
by Marge Bot (＠marge-bot) 01 Jul '26
01 Jul '26
Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC
Commits:
40412093 by Duncan Coutts at 2026-07-01T10:34:50-04:00
Add a test for thread scheduler fairness
It also tests that the interval timer and context switching works.
We also test that fairness is lost when the context switching interval
is too coarse for the duration of the test.
We add this test before doing surgery on the interval timer, so we have
decent coverage.
- - - - -
3f34d557 by Duncan Coutts at 2026-07-01T10:34:50-04:00
Make exported stop/startTimer no-ops, and rename internal functions
Specifically, internally rename:
stop/startTimer to pause/unpauseTimer
stop/startTicker to pause/unpauseTicker
and keep stop/startTimer as exported functions, but now as no-ops.
In the past the stop/startTicker actions were used incorrectly as if
they were synchronous, which they are not. See issue #27105. We now
document pause/unpackTicker as being async and not to be used for the
purpose of concurrency safety.
The existing stop/startTimer (note Timer not Ticker, the Timer calls the
Ticker!) are also exported from the RTS as a public API. This was
historically because the ticker used signals and it was important to
suspend the timer signel over a process fork. So these functions were
exported to be used by the process and unix libraries.
We cannot just remove the RTS exports, but we now make them no-ops, and
they can be removed from the process and unix library later. This
was already documented in a changelog.d entry no-more-timer-signal but
due to changes during the MR process the change to make stop/startTicker
into no-ops didn't make it into the earlier MR.
- - - - -
02e84e5f by Duncan Coutts at 2026-07-01T10:34:51-04:00
Make exitTicker/exitTimer unconditionally synchronous
We never use them asynchronously, and we should never need to do so.
And update some related comments.
- - - - -
13db6a72 by Duncan Coutts at 2026-07-01T10:34:51-04:00
posix ticker: update and improve comments on (un)pause and exit
Clarify what is async vs sync.
- - - - -
43d9a07d by Duncan Coutts at 2026-07-01T10:34:51-04:00
posix ticker: split out ppoll/select helper functions
Move the #ifdefs out of the main code body by introducing local helper
functions and types, which themselves have two implementations (with a
common API) based on ppoll or select.
This helps improve clarity/readability.
- - - - -
a5491baa by Duncan Coutts at 2026-07-01T10:34:51-04:00
posix ticker: improve the implementation
The existing implementation supported pausing and exiting, with the
implementation of pausing reling on a mutex and condition variable.
It needed to check the pause and stop shared variables on every
iteration. It relies on ppoll or select, to wait on the timeout and also
wait on an interrupt fd. The interrupt fd was only used for prompt
exit/shutdown, and not for pausing or other notification. The pause only
needed a lock and a memory operation, but the pause was not prompt. The
resume used a lock, and signaling a cond var.
The new implementation uses a somewhat more regular design: every
notification is done by setting a shared variable and
interrupting/notifying the ticker via the fd. The ticker thread does not
need to check any shared variables on normal timer expiry, only when it
recevies notification. This may be a micro-optimisation, but the tick
occurs 100 times a second by default so any improvements in the hot path
are amplified. When the ticker thread does receive notification it can
check the various shared variables and update its local state. The
blocking relies on using ppoll/select but without a timeout. This avoids
the condition var and also allows further notifications when paused
(also used for unpausing).
This design can be extended with further notification types if needed by
using and checking further shared vars (or making existing shared vars
an enum or counter). This may be used in future for additional
notifications to the ticker thread. This will likely be used to proxy
wakeUpRts from a single handler context for example. And this approach,
avoiding mutexes, is compatible with use from signal handlers.
So overall, it's:
* slightly simpler / more regular;
* easier to extend with additional notifications;
* probably slightly more efficient (but a micro-optimisation);
* and supports calling notification from signal handlers
- - - - -
5b20821e by Duncan Coutts at 2026-07-01T10:34:51-04:00
posix ticker: further minor local renaming for code clarity
Improve the clarity with better choice of names for several local vars
and function.
- - - - -
1f3ec5e0 by Duncan Coutts at 2026-07-01T10:34:51-04:00
win32 ticker: split out local helper functions
- - - - -
596e7307 by Duncan Coutts at 2026-07-01T10:34:51-04:00
win32 ticker: provide guarantee about concurrency and idempotency
Use a lock to ensure pause/unpause can be used concurrently. Use a
paused variable, protected by the lock, to ensure that pause and unpause
are both idempotent. This is what the portable API expects.
- - - - -
1870edd7 by Duncan Coutts at 2026-07-01T10:34:51-04:00
win32 ticker: make the initial tick be after one wait interval
There is no need to tick immediately. This is consistent with the
posix implementation.
- - - - -
7c15ab5b by Duncan Coutts at 2026-07-01T10:34:51-04:00
ticker: remove now-unnecessary layer of enable/disable
There was an atomic variable used to block *part* of the actions of the
tick handler. This still did not make stopTimer synchronous, even for
the part of the the handle_tick actions it covered. It also added a more
expensive (sequentuially consistent) atomic operation in the hot path
for the handle_tick action, whereas our new design requires no atomic
ops at all.
Now that we have eliminate the need for synchronous stop/startTicker,
we don't need this not-quite-working-anyway atomic protocol. The new
pause/unpauseTicker is explicitly asynchronous and idempotent.
- - - - -
8585f8cb by Duncan Coutts at 2026-07-01T10:34:51-04:00
ticker: add TODOs about issue #27250: too much being done from handle_tick
The handle_tick should not perform I/O, block, perform long-running
operations or call arbitrary user code. Unfortunately, everything to
do with the eventlog (at the moment) falls into all those categories.
- - - - -
10 changed files:
- rts/RtsStartup.c
- rts/Schedule.c
- rts/Ticker.h
- rts/Timer.c
- rts/Timer.h
- rts/include/rts/Timer.h
- rts/posix/Ticker.c
- rts/win32/Ticker.c
- + testsuite/tests/concurrent/should_run/T27105.hs
- testsuite/tests/concurrent/should_run/all.T
Changes:
=====================================
rts/RtsStartup.c
=====================================
@@ -415,8 +415,8 @@ hs_init_ghc(int *argc, char **argv[], RtsConfig rts_config)
traceInitEvent(dumpIPEToEventLog);
initHeapProfiling();
- /* start the virtual timer 'subsystem'. */
- startTimer();
+ /* start the timer (after initTimer above) */
+ unpauseTimer();
#if defined(RTS_USER_SIGNALS)
if (RtsFlags.MiscFlags.install_signal_handlers) {
@@ -512,14 +512,12 @@ hs_exit_(bool wait_foreign)
}
#endif
- /* stop the ticker */
- stopTimer();
- /*
- * it is quite important that we wait here as some timer implementations
- * (e.g. pthread) may fire even after we exit, which may segfault as we've
- * already freed the capabilities.
+ /* We rely on the guarantee that exitTimer stops the timer synchronously,
+ * which ensures the timer handler does not get run again after this point.
+ * We are about to start freeing resources used by the timer handler (like
+ * the capabilities, eventlog and profiling data structures).
*/
- exitTimer(true);
+ exitTimer();
/*
* Dump the ticky counter definitions
=====================================
rts/Schedule.c
=====================================
@@ -455,7 +455,7 @@ run_thread:
prev = setRecentActivity(ACTIVITY_YES);
if (prev == ACTIVITY_DONE_GC) {
#if !defined(PROFILING)
- startTimer();
+ unpauseTimer();
#endif
}
break;
@@ -1936,7 +1936,7 @@ delete_threads_and_gc:
// it will get re-enabled if we run any threads after the GC.
setRecentActivity(ACTIVITY_DONE_GC);
#if !defined(PROFILING)
- stopTimer();
+ pauseTimer();
#endif
break;
}
@@ -2232,8 +2232,8 @@ forkProcess(HsStablePtr *entry
generations[g].threads = END_TSO_QUEUE;
}
- // On Unix, all timers are reset in the child, so we need to start
- // the timer again.
+ // The timer thread is not present in the child process, so we need
+ // to initialise the timer again.
initTimer();
// TODO: need to trace various other things in the child
@@ -2244,7 +2244,7 @@ forkProcess(HsStablePtr *entry
// start timer after the IOManager is initialized
// (the idle GC may wake up the IOManager)
- startTimer();
+ unpauseTimer();
// Install toplevel exception handlers, so interruption
// signal will be sent to the main thread.
=====================================
rts/Ticker.h
=====================================
@@ -12,9 +12,44 @@
typedef void (*TickProc)(int);
-void initTicker (Time interval, TickProc handle_tick);
-void startTicker (void);
-void stopTicker (void);
-void exitTicker (bool wait);
+/* The ticker is initialised in a paused state. Use unpauseTicker to start. */
+void initTicker(Time interval, TickProc handle_tick);
+
+/* Stop and terminate the ticker. It does not need to be stopped first.
+ * The exitTicker action is *synchronous*. When it returns the caller is
+ * guaranteed that the tick action is blocked.
+ */
+void exitTicker(void);
+
+/* Pause and unpause (resume) the ticker.
+ *
+ * The pauseTicker and unpauseTicker actions are *asynchronous*. After calling
+ * pauseTicker, the ticker will pause eventually, but there may be another tick
+ * action before it does pause (and theoretically there could be several but
+ * in practice this is unlikely). Similarly, after calling unpauseTicker the
+ * ticker will start up again eventually, but there is an unspecified delay
+ * between the unpause and the next tick action (but in practice it is short).
+ *
+ * This should be used for the purpose of *efficiency*: to avoid unnecessary
+ * OS thread wakeups caused by the ticker.
+ *
+ * These should *not* be used for the purpose of *concurrency safety*: to
+ * prevent the tick action from running concurrently with some other critical
+ * section. The synchronous case is not provided because it is not currently
+ * needed (and proper locking is often a better solution anyway).
+ *
+ * The pairing of unpauseTicker and the handle_tick action form a
+ * synchonises-with relation: values written before unpauseTicker can be
+ * read from the resulting handle_tick action.
+ *
+ * It *is* safe to call these functions from within the tick handler itself.
+ *
+ * It is safe to use these functions concurrently from multiple threads, but
+ * note that they *are* idempotent. This means it is not appropriate to use
+ * paired pause/unpause calls concurrently. They can be used by threads based
+ * on consistent use of some shared state or observation.
+ */
+void pauseTicker(void);
+void unpauseTicker(void);
#include "EndPrivate.h"
=====================================
rts/Timer.c
=====================================
@@ -28,15 +28,6 @@
#include "RtsSignals.h"
#include "rts/EventLogWriter.h"
-// This global counter is used to allow multiple threads to stop the
-// timer temporarily with a stopTimer()/startTimer() pair. If
-// timer_enabled == 0 timer is enabled
-// timer_disabled == N, N > 0 timer is disabled by N threads
-// When timer_enabled makes a transition to 0, we enable the timer,
-// and when it makes a transition to non-0 we disable it.
-
-static StgWord timer_disabled;
-
/* ticks left before next pre-emptive context switch */
static int ticks_to_ctxt_switch = 0;
@@ -107,9 +98,9 @@ static
void
handle_tick(int unused STG_UNUSED)
{
- handleProfTick();
- if (RtsFlags.ConcFlags.ctxtSwitchTicks > 0
- && SEQ_CST_LOAD_ALWAYS(&timer_disabled) == 0)
+ handleProfTick(); // Bad or worse: see issue #27250.
+
+ if (RtsFlags.ConcFlags.ctxtSwitchTicks > 0)
{
ticks_to_ctxt_switch--;
if (ticks_to_ctxt_switch <= 0) {
@@ -123,7 +114,7 @@ handle_tick(int unused STG_UNUSED)
ticks_to_eventlog_flush--;
if (ticks_to_eventlog_flush <= 0) {
ticks_to_eventlog_flush = RtsFlags.TraceFlags.eventlogFlushTicks;
- flushEventLog(NULL);
+ flushEventLog(NULL); // Bad or worse: see issue #27250.
}
}
#endif
@@ -148,7 +139,7 @@ handle_tick(int unused STG_UNUSED)
RtsFlags.MiscFlags.tickInterval;
#if defined(THREADED_RTS)
wakeUpRts();
- // The scheduler will call stopTimer() when it has done
+ // The scheduler will call pauseTimer() when it has done
// the GC.
#endif
} else {
@@ -160,10 +151,10 @@ handle_tick(int unused STG_UNUSED)
#if defined(PROFILING)
if (!(RtsFlags.ProfFlags.doHeapProfile
|| RtsFlags.CcFlags.doCostCentres)) {
- stopTimer();
+ pauseTimer();
}
#else
- stopTimer();
+ pauseTimer();
#endif
}
} else {
@@ -176,48 +167,49 @@ handle_tick(int unused STG_UNUSED)
}
}
-void
-initTimer(void)
+void initTimer(void)
{
#if defined(HAVE_PREEMPTION)
initProfTimer();
if (RtsFlags.MiscFlags.tickInterval != 0) {
initTicker(RtsFlags.MiscFlags.tickInterval, handle_tick);
}
- SEQ_CST_STORE_ALWAYS(&timer_disabled, 1);
#endif
}
-void
-startTimer(void)
+/* Deprecated exported functions. Now no-ops.
+ * Historically they were used by the process and unix libraries to disable
+ * the signal-based interval timer, since otherwise the timer signal would
+ * keep going off in the child process and confusing everything. The interval
+ * timer no longer uses signals, so there is no need any more for libraries to
+ * disable the timer. Also, the timer internal API has changed.
+ */
+void stopTimer(void) { /* no-op */ }
+void startTimer(void) { /* no-op */ }
+
+void pauseTimer(void)
{
#if defined(HAVE_PREEMPTION)
- if (SEQ_CST_SUB_ALWAYS(&timer_disabled, 1) == 0) {
- if (RtsFlags.MiscFlags.tickInterval != 0) {
- startTicker();
- }
+ if (RtsFlags.MiscFlags.tickInterval != 0) {
+ pauseTicker();
}
#endif
}
-void
-stopTimer(void)
+void unpauseTimer(void)
{
#if defined(HAVE_PREEMPTION)
- if (SEQ_CST_ADD_ALWAYS(&timer_disabled, 1) == 1) {
- if (RtsFlags.MiscFlags.tickInterval != 0) {
- stopTicker();
- }
+ if (RtsFlags.MiscFlags.tickInterval != 0) {
+ unpauseTicker();
}
#endif
}
-void
-exitTimer (bool wait)
+void exitTimer (void)
{
#if defined(HAVE_PREEMPTION)
if (RtsFlags.MiscFlags.tickInterval != 0) {
- exitTicker(wait);
+ exitTicker();
}
#endif
}
=====================================
rts/Timer.h
=====================================
@@ -8,5 +8,12 @@
#pragma once
-RTS_PRIVATE void initTimer (void);
-RTS_PRIVATE void exitTimer (bool wait);
+#include "BeginPrivate.h"
+
+void initTimer(void);
+void exitTimer(void);
+
+void pauseTimer(void);
+void unpauseTimer(void);
+
+#include "EndPrivate.h"
=====================================
rts/include/rts/Timer.h
=====================================
@@ -13,6 +13,6 @@
#pragma once
-void startTimer (void);
-void stopTimer (void);
+void startTimer (void); // Deprecated: see issue #27073
+void stopTimer (void); // Deprecated: see issue #27073
int rtsTimerSignal (void); // Deprecated: see issue #27073
=====================================
rts/posix/Ticker.c
=====================================
@@ -103,120 +103,112 @@
#include <unistd.h>
#include <fcntl.h>
-static Time itimer_interval = DEFAULT_TICK_INTERVAL;
-// Should we be firing ticks?
-// Writers to this must hold the mutex below.
-static bool stopped = false;
+// Forward declarations of local types and helper functions to hide the
+// difference between ppoll() and select()
+#if defined(HAVE_DECL_PPOLL) && HAVE_DECL_PPOLL == 1
+typedef struct timespec timeout; // for ppoll()
+typedef struct { struct pollfd pollfds[1]; } fdset;
+#else
+typedef struct timeval timeout; // for select()
+typedef struct { int fd; fd_set selectfds; } fdset; // need to stash fd
+#endif
+static void poll_init_timeout(timeout *tv, Time t);
+static void poll_init_fdset(fdset *fds, int fd); // single fd only
+// poll_*_timeout returns >0 if fd ready, ==0 if timeout, <0 if error
+static int poll_no_timeout(fdset *fdset);
+static int poll_with_timeout(fdset *fdset, timeout *t);
+
+
+static Time ticker_interval = DEFAULT_TICK_INTERVAL;
-// should the ticker thread exit?
-// This can be set without holding the mutex.
-static bool exited = true;
+// Atomic variable used by client threads to communicate that they want the
+// ticker thread to pause. This communication is one-way, with no
+// acknowledgement.
+static bool pause_request;
-// Signaled when we want to (re)start the timer
-static Condition start_cond;
-static Mutex mutex;
-static OSThreadId thread;
+// Atomic variable used by other threads to communicate that they want the
+// ticker thread to exit.
+static bool exit_request;
-// fds for interrupting the ticker
-static int interruptfd_r = -1, interruptfd_w = -1;
+// Used to wait for the ticker thread to terminate after asking it to exit.
+static OSThreadId ticker_thread_id;
-static void *itimer_thread_func(void *_handle_tick)
+// Fds used with sendFdWakeup to notify the ticker thread that any of the
+// *_request variables above have been set.
+static int notifyfd_r = -1, notifyfd_w = -1;
+
+static void *ticker_thread_func(void *_handle_tick)
{
TickProc handle_tick = _handle_tick;
-#if defined(HAVE_DECL_PPOLL) && HAVE_DECL_PPOLL == 1
- struct pollfd pollfds[1];
+ // Thread-local view of our state. We compare these with the corresponding
+ // atomic shared variables used to request state changes.
+ bool paused = true; // updated from atomic shared var pause_request
+ bool exit = false; // updated from atomic shared var exit_request
+ // Note that we start paused.
- pollfds[0].fd = interruptfd_r;
- pollfds[0].events = POLLIN;
+ timeout timeout;
+ fdset fdset;
+ poll_init_timeout(&timeout, ticker_interval);
+ poll_init_fdset(&fdset, notifyfd_r);
- struct timespec ts = { .tv_sec = TimeToSeconds(itimer_interval)
- , .tv_nsec = TimeToNS(itimer_interval) % 1000000000
- };
-#else
- fd_set selectfds;
- FD_ZERO(&selectfds);
- FD_SET(interruptfd_r, &selectfds);
-
- struct timeval tv = { .tv_sec = TimeToSeconds(itimer_interval)
- /* convert remainder time in nanoseconds
- to microseconds, rounding up: */
- , .tv_usec = ((TimeToNS(itimer_interval) % 1000000000)
- + 999) / 1000
- };
-#endif
+ while (!exit) {
- // Relaxed is sufficient: If we don't see that exited was set in one iteration we will
- // see it next time.
- while (!RELAXED_LOAD_ALWAYS(&exited)) {
-
-#if defined(HAVE_DECL_PPOLL) && HAVE_DECL_PPOLL == 1
- int nfds = 1;
- int nready = ppoll(pollfds, nfds, &ts, NULL);
-#else
- struct timeval tv_tmp = tv; // copy since select may change this value.
- int nfds = interruptfd_r+1;
- int nready = select(nfds, &selectfds, NULL, NULL, &tv_tmp);
-#endif
- // In either case (ppoll or select), the result nready is the number
- // of fds that are ready.
- if (RTS_LIKELY(nready == 0)) {
- // Timer expired, not interrupted, continue.
- } else if (nready > 0) {
- // We only monitor one fd (the interruptfd_r), so we know
- // it is that fd that is ready without any further checks.
- collectFdWakeup(interruptfd_r);
- // No further action needed, continue on to handling the final tick
- // and then stop.
-
- // Note that we rely on sendFdWakeup and select/poll to provide the
- // happens-before relation. So if 'exited' was set before calling
- // sendFdWakeup, then we should be able to reliably read it after.
- // And thus reading 'exited' in the while loop guard is ok.
+ int notify;
+ if (paused) {
+ notify = poll_no_timeout(&fdset);
} else {
- // While the RTS attempts to mask signals, some foreign libraries
- // that rely on signal delivery may unmask them. Consequently we
- // may see EINTR. See #24610.
- if (errno != EINTR) {
- sysErrorBelch("Ticker: poll failed: %s", strerror(errno));
- }
+ notify = poll_with_timeout(&fdset, &timeout);
}
- // first try a cheap test
- if (RELAXED_LOAD_ALWAYS(&stopped)) {
- OS_ACQUIRE_LOCK(&mutex);
- // should we really stop?
- if (stopped) {
- waitCondition(&start_cond, &mutex);
- }
- OS_RELEASE_LOCK(&mutex);
- } else {
+ if (RTS_LIKELY(notify == 0)) {
+ // The time expired, no state change notification.
handle_tick(0);
+
+ } else if (notify > 0) {
+ // State change notification, check the request variables.
+
+ // We rely on sendFdWakeup and select/poll to provide the
+ // happens-before relation. So if the request variables are set
+ // before calling sendFdWakeup, then we should be able to reliably
+ // read them here afterwards.
+ collectFdWakeup(notifyfd_r);
+
+ paused = ACQUIRE_LOAD_ALWAYS(&pause_request);
+ exit = RELAXED_LOAD_ALWAYS(&exit_request);
+ } else if (errno != EINTR) {
+ // While the RTS attempts to mask signals, some foreign libraries
+ // that rely on signal delivery may unmask them. Consequently we
+ // may see EINTR. See #24610.
+ sysErrorBelch("Ticker: poll failed: %s", strerror(errno));
}
}
return NULL;
}
+/* Initialise the ticker on startup or re-initialise the ticker after a fork().
+ * In the fork case, the thread will not be present, but fds are inherited.
+ *
+ * The ticker is started in the paused state. Use unpauseTicker to continue.
+ */
void
initTicker (Time interval, TickProc handle_tick)
{
- itimer_interval = interval;
- stopped = true;
- exited = false;
+ ticker_interval = interval;
+ pause_request = true;
+ exit_request = false;
+
#if defined(HAVE_SIGNAL_H)
sigset_t mask, omask;
int sigret;
#endif
int ret;
- initCondition(&start_cond);
- initMutex(&mutex);
-
/* Open the interrupt fd synchronously.
*
- * We used to do it in itimer_thread_func (i.e. in the timer thread) but it
+ * We used to do it in ticker_thread_func (i.e. in the timer thread) but it
* meant that some user code could run before it and get confused by the
* allocation of the timerfd.
*
@@ -226,11 +218,11 @@ initTicker (Time interval, TickProc handle_tick)
* descriptor closed by the first call! (see #20618)
*/
- if (interruptfd_r != -1) {
+ if (notifyfd_r != -1) {
// don't leak the old file descriptors after a fork (#25280)
- closeFdWakeup(interruptfd_r, interruptfd_w);
+ closeFdWakeup(notifyfd_r, notifyfd_w);
}
- newFdWakeup(&interruptfd_r, &interruptfd_w);
+ newFdWakeup(¬ifyfd_r, ¬ifyfd_w);
/*
* Create the thread with all blockable signals blocked, leaving signal
@@ -242,7 +234,7 @@ initTicker (Time interval, TickProc handle_tick)
sigfillset(&mask);
sigret = pthread_sigmask(SIG_SETMASK, &mask, &omask);
#endif
- ret = createAttachedOSThread(&thread, "ghc_ticker", itimer_thread_func, (void*)handle_tick);
+ ret = createAttachedOSThread(&ticker_thread_id, "ghc_ticker", ticker_thread_func, (void*)handle_tick);
#if defined(HAVE_SIGNAL_H)
if (sigret == 0)
pthread_sigmask(SIG_SETMASK, &omask, NULL);
@@ -253,47 +245,112 @@ initTicker (Time interval, TickProc handle_tick)
}
}
-void
-startTicker(void)
+/* Asynchronous. Idempotent. */
+void unpauseTicker(void)
{
- OS_ACQUIRE_LOCK(&mutex);
- RELAXED_STORE(&stopped, false);
- signalCondition(&start_cond);
- OS_RELEASE_LOCK(&mutex);
+ RELEASE_STORE_ALWAYS(&pause_request, false);
+ sendFdWakeup(notifyfd_w);
}
-/* There may be at most one additional tick fired after a call to this */
-void
-stopTicker(void)
+/* Asynchronous. Idempotent.
+ * There may be at additional ticks fired after a call to this, but it will
+ * usually stop quickly.
+ */
+void pauseTicker(void)
{
- OS_ACQUIRE_LOCK(&mutex);
- RELAXED_STORE(&stopped, true);
- OS_RELEASE_LOCK(&mutex);
+ RELEASE_STORE_ALWAYS(&pause_request, true);
+ sendFdWakeup(notifyfd_w);
}
-/* There may be at most one additional tick fired after a call to this */
-void
-exitTicker (bool wait)
+/* Synchronous. Not idempotent.
+ * The ticker is guaranteed stopped after this.
+ */
+void exitTicker(void)
{
- ASSERT(!SEQ_CST_LOAD(&exited));
- SEQ_CST_STORE(&exited, true);
- // ensure that ticker wakes up if stopped
- startTicker();
- sendFdWakeup(interruptfd_w);
-
- // wait for ticker to terminate if necessary
- if (wait) {
- if (pthread_join(thread, NULL)) {
- sysErrorBelch("Ticker: Failed to join: %s", strerror(errno));
- }
- closeFdWakeup(interruptfd_r, interruptfd_w);
- closeMutex(&mutex);
- closeCondition(&start_cond);
- } else {
- pthread_detach(thread);
+ ASSERT(!RELAXED_LOAD_ALWAYS(&exit_request));
+ RELEASE_STORE_ALWAYS(&exit_request, true);
+ sendFdWakeup(notifyfd_w);
+
+ // wait for ticker thread to terminate
+ if (pthread_join(ticker_thread_id, NULL)) {
+ sysErrorBelch("Ticker: Failed to join: %s", strerror(errno));
}
+ closeFdWakeup(notifyfd_r, notifyfd_w);
+}
+
+/* Implementation of the local helpers, to hide the difference between ppoll()
+ * and select().
+ */
+#if defined(HAVE_DECL_PPOLL) && HAVE_DECL_PPOLL == 1
+static void poll_init_timeout(timeout *tv, Time t)
+{
+ tv->tv_sec = TimeToSeconds(t);
+ tv->tv_nsec = TimeToNS(t) % 1000000000;
+}
+
+static void poll_init_fdset(fdset *fds, int fd)
+{
+ fds->pollfds[0].fd = fd;
+ fds->pollfds[0].events = POLLIN;
+}
+
+static int poll_no_timeout(fdset *fds)
+{
+ int nfds = 1;
+ return ppoll(fds->pollfds, nfds, NULL, NULL);
+}
+
+static int poll_with_timeout(fdset *fds, timeout *ts)
+{
+ int nfds = 1;
+ return ppoll(fds->pollfds, nfds, ts, NULL);
+}
+
+#else // select()
+
+static void poll_init_timeout(timeout *tv, Time t)
+{
+ tv->tv_sec = TimeToSeconds(t);
+ /* convert remainder time in nanoseconds to microseconds, rounding up: */
+ tv->tv_usec = ((TimeToNS(t) % 1000000000) + 999) / 1000;
+}
+
+static void poll_init_fdset(fdset *fds, int fd)
+{
+ /* select() modifies the fd_set: it uses the same fd_set for reporting as
+ * for input. Thus we must rebuild it every time. We can optimise this
+ * rebuilding somewhat however if we rely on select() not modifying the
+ * bits that we didn't ask it to look at. So we can zero the fd_set just
+ * once, and then only reset the single bit for the single fd, before each
+ * call to selct().
+ */
+ fds->fd = fd;
+ FD_ZERO(&fds->selectfds);
+}
+
+static int poll_no_timeout(fdset *fds)
+{
+ /* select() modifies the fd_set so we must set it every time, but we rely
+ * on it not touching other bits to avoid having to FD_ZERO it every time
+ */
+ FD_SET(fds->fd, &fds->selectfds);
+ int nfds = fds->fd+1;
+ return select(nfds, &fds->selectfds, NULL, NULL, NULL);
+}
+
+static int poll_with_timeout(fdset *fds, timeout *tv)
+{
+ struct timeval tv_tmp = *tv; // copy since select may change this value.
+ /* select() modifies the fd_set so we must set it every time, but we rely
+ * on it not touching other bits to avoid having to FD_ZERO it every time
+ */
+ FD_SET(fds->fd, &fds->selectfds);
+ int nfds = fds->fd+1;
+ return select(nfds, &fds->selectfds, NULL, NULL, &tv_tmp);
}
+#endif
+/* This is obsolete, but is used in the unix package for now */
int
rtsTimerSignal(void)
{
=====================================
rts/win32/Ticker.c
=====================================
@@ -11,7 +11,11 @@
static TickProc tick_proc = NULL;
static HANDLE timer_queue = NULL;
+
+static Mutex lock; // To protect the timer and paused var below
static HANDLE timer = NULL;
+static bool paused;
+
static Time tick_interval = 0;
static VOID CALLBACK tick_callback(
@@ -36,12 +40,19 @@ static VOID CALLBACK tick_callback(
// This seems to be the case starting at some point during the
// Windows 7 lifetime and any newer versions of windows.
+// Forward decls
+static void startTicker(void);
+static void stopTicker(bool synchronous);
+
void
initTicker (Time interval, TickProc handle_tick)
{
+ ASSERT(timer_queue == NULL);
tick_interval = interval;
tick_proc = handle_tick;
+ OS_INIT_LOCK(&lock);
+ paused = true; // starts paused
timer_queue = CreateTimerQueue();
if (timer_queue == NULL) {
sysErrorBelch("CreateTimerQueue");
@@ -49,39 +60,81 @@ initTicker (Time interval, TickProc handle_tick)
}
}
+// Asynchronous. Idempotent.
void
-startTicker(void)
+unpauseTicker(void)
{
- BOOL r;
-
- r = CreateTimerQueueTimer(&timer,
- timer_queue,
- tick_callback,
- 0,
- 0,
- TimeToMS(tick_interval), // ms
- WT_EXECUTEINTIMERTHREAD);
- if (r == 0) {
- sysErrorBelch("CreateTimerQueueTimer");
- stg_exit(EXIT_FAILURE);
+ OS_ACQUIRE_LOCK(&lock);
+ if (paused) {
+ startTicker();
}
+ paused = false;
+ OS_RELEASE_LOCK(&lock);
}
+// Asynchronous. Idempotent.
void
-stopTicker(void)
+pauseTicker(void)
{
- if (timer_queue != NULL && timer != NULL) {
- DeleteTimerQueueTimer(timer_queue, timer, NULL);
- timer = NULL;
+ OS_ACQUIRE_LOCK(&lock);
+ if (!paused) {
+ /* pauseTicker is called from within the handle_tick, so stopping
+ * the ticker here /must/ be asynchronous or we will deadlock! */
+ stopTicker(false /* asynchronous */);
}
+ paused = true;
+ OS_RELEASE_LOCK(&lock);
}
void
-exitTicker (bool wait)
+exitTicker(void)
{
- stopTicker();
- if (timer_queue != NULL) {
- DeleteTimerQueueEx(timer_queue, wait ? INVALID_HANDLE_VALUE : NULL);
- timer_queue = NULL;
+ ASSERT(timer_queue != NULL);
+
+ OS_ACQUIRE_LOCK(&lock);
+ if (!paused) {
+ stopTicker(true /* synchronous */);
+ }
+ OS_RELEASE_LOCK(&lock);
+
+ // From the docs for DeleteTimerQueueEx:
+ // If this parameter is INVALID_HANDLE_VALUE, the function waits
+ // for all callback functions to complete before returning.
+ // This is a belt-and-braces approach to ensuring exitTicker is synchronous,
+ // since stopTicker(true) is already synchronous and there's only one timer.
+ HANDLE completion = INVALID_HANDLE_VALUE;
+ DeleteTimerQueueEx(timer_queue, completion);
+ timer_queue = NULL;
+}
+
+static void startTicker(void) {
+ ASSERT(timer_queue != NULL && timer == NULL);
+ DWORD interval = TimeToMS(tick_interval); // ms
+ BOOL r = CreateTimerQueueTimer(&timer,
+ timer_queue,
+ tick_callback,
+ NULL, // callback param
+ interval, // inital interval
+ interval, // recurrant interval
+ WT_EXECUTEINTIMERTHREAD);
+ //TODO: using WT_EXECUTEINTIMERTHREAD is fine for context switching, and
+ // plausibly also ok for profile sampling but is way out for eventlog
+ // flushing. The eventlog flush does a global synchronisation of all
+ // capabilities and I/O! And with eventlog providers, it calls arbitrary
+ // user code. This is not ok! See issue #27250.
+ if (r == 0) {
+ sysErrorBelch("CreateTimerQueueTimer");
+ stg_exit(EXIT_FAILURE);
}
+ ASSERT(timer != NULL);
+}
+
+static void stopTicker(bool synchronous) {
+ ASSERT(timer_queue != NULL && timer != NULL);
+ // From the docs for DeleteTimerQueueTimer:
+ // If this parameter is INVALID_HANDLE_VALUE, the function waits for any
+ // running timer callback functions to complete before returning.
+ HANDLE completion = synchronous ? INVALID_HANDLE_VALUE : NULL;
+ DeleteTimerQueueTimer(timer_queue, timer, completion);
+ timer = NULL;
}
=====================================
testsuite/tests/concurrent/should_run/T27105.hs
=====================================
@@ -0,0 +1,114 @@
+{-# OPTIONS_GHC -fno-omit-yields #-}
+
+import Control.Monad
+import Control.Monad.ST
+import Control.Concurrent
+import Control.Exception
+import System.Exit
+import System.Mem
+import GHC.Arr
+import Prelude hiding (init)
+
+-- Test thread fairness:
+-- run two cpu-bound threads concurrently for a second,
+-- each counts how many operations it can perform until signaled to stop
+-- expect a balance between the two with no more than a 75% imperfection.
+-- Yes, 75%! On the CI machines we occasionally observe extraordinary levels
+-- of unfairness: nearly 60% in some cases. We don't want this to become a
+-- fragile test that is ignored, so we use an extreme bound. This should still
+-- catch gross breakage.
+--
+-- This _should_ detect if the interval timer is not working, or if thread
+-- context switching is messed up. We can expect failure if we force a
+-- contex switch interval of more than half the test time, i.e. more than 0.5s
+--
+-- We run the test twice, with allocating and non-allocating worker threads.
+-- The -fno-omit-yields above is crucial for worker_nonalloc below, or it never
+-- gets interrupted and thus no context switches.
+
+main :: IO ()
+main = do
+ test worker_alloc
+ performMajorGC
+ test worker_nonalloc
+
+test :: Worker -> IO ()
+test worker = do
+ stop <- newEmptyMVar
+ res1 <- newEmptyMVar
+ res2 <- newEmptyMVar
+ _ <- forkIO (worker stop >>= putMVar res1)
+ _ <- forkIO (worker stop >>= putMVar res2)
+ threadDelay 300_000
+ -- Let them run for 300ms. The default context switch interval is 20ms.
+ -- This gives time for 15 context switches, so this _should_ be enough
+ -- to get less than 10% unfairness. And on most platforms it is enough.
+ -- But OSX! Oh OSX! How do I loath thee? Let me count++ the ways.
+ -- To avoid a fragile test, we use a 75% unfairness threshold.
+ putMVar stop ()
+ count1 <- takeMVar res1
+ count2 <- takeMVar res2
+ let balance :: Double
+ balance = abs ((fromIntegral count1 - fromIntegral count2)
+ / fromIntegral count2)
+ when (balance > 0.75) $ do
+ putStrLn "Schedule fairness more than 75% tolerance:"
+ putStrLn $ "imperfection: " ++ show (balance * 100) ++ "%"
+ putStrLn $ "work counts: " ++ show (count1, count2)
+ exitFailure
+
+type Worker = MVar () -> IO Int
+
+-- count how many iterations we can calculate until we're signaled to stop
+worker_template :: IO a -> (a -> IO ()) -> MVar () -> IO Int
+worker_template init iter stop = do
+ a <- init
+ go a 0
+ where
+ go a !count = do
+ ok <- tryReadMVar stop
+ case ok of
+ Just () -> return count
+ Nothing -> do
+ iter a
+ go a (count + 1)
+
+
+-- the allocating worker
+{-# NOINLINE worker_alloc #-}
+worker_alloc :: Worker
+worker_alloc =
+ worker_template
+ (return 18)
+ (\n -> evaluate (fib n) >> return ())
+
+-- by forcing this to be Integer we cause lots of allocation!
+fib :: Integer -> Integer
+fib 0 = 0
+fib 1 = 1
+fib n = fib (n-1) + fib (n-2)
+
+
+-- the non-allocating worker
+{-# NOINLINE worker_nonalloc #-}
+worker_nonalloc :: Worker
+worker_nonalloc =
+ worker_template
+ (stToIO $ newSTArray (0,50_000) 42)
+ (\arr -> stToIO $ arrrev arr)
+
+arrrev :: STArray s Int Int -> ST s ()
+arrrev arr =
+ let (i,j) = boundsSTArray arr
+ in arrrev_go arr i j
+
+{-# NOINLINE arrrev_go #-}
+arrrev_go :: STArray s Int Int -> Int -> Int -> ST s ()
+arrrev_go !_ !i !j | i >= j = return ()
+arrrev_go !arr !i !j = do
+ x <- readSTArray arr i
+ y <- readSTArray arr j
+ writeSTArray arr i y
+ writeSTArray arr j x
+ arrrev_go arr (i+1) (j-1)
+
=====================================
testsuite/tests/concurrent/should_run/all.T
=====================================
@@ -325,3 +325,15 @@ test('T26341b'
# test uses pipe operations which are not supported by the JS/wasm backends
, when(arch('wasm32') or arch('javascript'), skip)
, compile_and_run, ['-package process'])
+
+# Scheduler (very rough) fairness
+test('T27105',
+ [when(arch('wasm32'), skip), # same reason as T367_letnoescape
+ run_timeout_multiplier(0.05)], # we expect this to run for ~2s
+ compile_and_run, [''])
+test('T27105_fail',
+ [when(arch('wasm32'), skip),
+ # And we can expect it to fail if we context switch too coarsely
+ extra_run_opts('+RTS -C0.2 -RTS'), expect_fail,
+ run_timeout_multiplier(0.05)],
+ multimod_compile_and_run, ['T27105.hs', ''])
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/1a8a24f4386e7838403212cb87b32d…
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[Git][ghc/ghc][master] 20 commits: gitlab-ci: Drop vestigial references to make build system
by Marge Bot (＠marge-bot) 01 Jul '26
by Marge Bot (＠marge-bot) 01 Jul '26
01 Jul '26
Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC
Commits:
701088db by Ben Gamari at 2026-07-01T10:34:03-04:00
gitlab-ci: Drop vestigial references to make build system
- - - - -
62d54a53 by Ben Gamari at 2026-07-01T10:34:03-04:00
gitlab-ci: Add support for running specifying a job's testsuite ways
- - - - -
7f97ac2c by Ben Gamari at 2026-07-01T10:34:03-04:00
gitlab-ci: Run llvm testsuite ways in llvm jobs
Addresses #25762.
- - - - -
7ea75116 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Add normalise_ddump_deriv setup function
Some tests check the result of -ddump-deriv, which may contain INLINE pragmas depending on optimization flags.
With normalise_ddump_deriv setup function, INLINE pragmas are stripped off.
- - - - -
c7a8199f by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Use -dsuppress-idinfo to make tests more robust
Previously, T18052a and T21755 were failing on 'optasm' and 'optllvm' ways because of visibility of unfoldings.
- - - - -
a12122e5 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Use a trick to keep large objects alive
Previously, T17574 and T19381 were failing on 'optasm' and 'optllvm' ways because of compiler optimizations.
Change them to use NOINLINE to prevent unwanted optimizations.
- - - - -
1a95b327 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Only run T24224 in 'normal' way
This test is a frontend-only one and breaks if optimizations are enabled.
- - - - -
8abea737 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Ignore T18118's stderr
When optimizations are enabled, the compiler emits a warning (You cannot SPECIALISE ...).
The message is not important, so ignore it.
- - - - -
9453a722 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Mark T816 and tc216 broken with optimizations
These tests are about type checking, so we should not care too much if they are broken with optimizations.
See #26952
- - - - -
0aef9ec0 by Ben Gamari at 2026-07-01T10:34:03-04:00
testsuite: ds014 is not longer broken
It now appears to pass in the ways it was marked as broken in.
Closes #14901.
- - - - -
4692d1e4 by Ben Gamari at 2026-07-01T10:34:03-04:00
testsuite: Only run stack cloning tests in the normal way
These are too dependent upon code generation specifics to pass in most
other ways.
- - - - -
c154df26 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Update options_ghc_fbyte-code
The `-fbyte-code` option used to be overriden by `-fllvm` but it is no longer true since !14872 was merged.
I updated the test to accept the new behavior.
Closes #27049
- - - - -
5d8bb7b5 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Only run T22744 in 'normal' way
This test takes a long time on optimized ways.
- - - - -
d1e74c8e by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Disable tests that use -finfo-table-map on llvm ways
Currently, -finfo-table-map does not work with -fllvm. See #26435
- - - - -
3bf38c84 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Don't run T24726 on optimized ways
If optimizations are enabled, the rewrite rule just fires and -drule-check will report nothing.
- - - - -
e4eef116 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Use -fno-unoptimized-core-for-interpreter when running LinkableUsage01/02
Optimizations for the bytecode interpreter are considered experimental, and need a flag to be enabled.
- - - - -
234a9872 by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Suppress unwanted optimizations on T25284
- - - - -
99a2af2f by ARATA Mizuki at 2026-07-01T10:34:03-04:00
testsuite: Don't run stack_big_ret with optimizations
Stack layout may change with optimizations enabled.
- - - - -
04c836df by ARATA Mizuki at 2026-07-01T10:34:04-04:00
testsuite: Mark memo001 broken on optimized ways
See #27396
- - - - -
1a8a24f4 by ARATA Mizuki at 2026-07-01T10:34:04-04:00
testsuite: Mark syn-perf broken on optimized ways
See #27398
- - - - -
34 changed files:
- .gitlab/ci.sh
- .gitlab/generate-ci/gen_ci.hs
- .gitlab/jobs.yaml
- libraries/base/tests/all.T
- libraries/ghc-heap/tests/all.T
- testsuite/driver/testlib.py
- testsuite/tests/arityanal/should_compile/T21755.stderr
- testsuite/tests/arityanal/should_compile/all.T
- testsuite/tests/bytecode/TLinkable/all.T
- testsuite/tests/cmm/should_compile/all.T
- testsuite/tests/core-to-stg/T25284/Cls.hs
- testsuite/tests/deSugar/should_fail/all.T
- testsuite/tests/deSugar/should_run/all.T
- testsuite/tests/deriving/should_compile/all.T
- testsuite/tests/driver/options_ghc/Mod_fbyte_code.hs
- testsuite/tests/driver/options_ghc/all.T
- testsuite/tests/driver/options_ghc/options_ghc_fbyte-code.stderr
- testsuite/tests/generics/GenDerivOutput.hs
- testsuite/tests/generics/GenDerivOutput1_0.hs
- testsuite/tests/generics/GenDerivOutput1_1.hs
- testsuite/tests/generics/T10604/T10604_deriving.hs
- testsuite/tests/generics/T10604/all.T
- testsuite/tests/generics/all.T
- testsuite/tests/perf/compiler/all.T
- testsuite/tests/printer/T18052a.stderr
- testsuite/tests/printer/all.T
- testsuite/tests/profiling/perf/T23103/all.T
- testsuite/tests/profiling/should_run/all.T
- testsuite/tests/rts/T17574.hs
- testsuite/tests/rts/T19381.hs
- testsuite/tests/rts/all.T
- testsuite/tests/rts/ipe/T24005/all.T
- testsuite/tests/simplCore/should_compile/all.T
- testsuite/tests/typecheck/should_compile/all.T
The diff was not included because it is too large.
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/3f00f234d0d5b3b3b2a23a5dc70ce3…
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[Git][ghc/ghc][wip/terrorjack/asan] 42 commits: Don't use global variables to address concurrency bugs! (fixes #27234)
by Cheng Shao (＠TerrorJack) 01 Jul '26
by Cheng Shao (＠TerrorJack) 01 Jul '26
01 Jul '26
Cheng Shao pushed to branch wip/terrorjack/asan at Glasgow Haskell Compiler / GHC
Commits:
9284a1f7 by Simon Hengel at 2026-06-23T05:55:33-04:00
Don't use global variables to address concurrency bugs! (fixes #27234)
This was originally introduce with
88f38b03025386f0f1e8f5861eed67d80495168a to address #17922.
In this specific case a better fix would have been to synchronize on
stderr:
withHandle_ "stderrSupportsAnsiColors" stderr $ \ _ -> do
...
But apparently the dependency on `terminfo` was removed in
32ab07bf3d6ce45e8ea5b55e8095174a6b42a7f0, preventing #17922 in the first
place.
- - - - -
44309cd3 by Alan Zimmerman at 2026-06-23T05:56:20-04:00
EPA: remove LocatedL / SrcSpanAnnL and LocatedLI / SrcSpanAnnLI
This is part of a refactor towards only having LocatedA / SrcSpanAnnA
It removes the stated items, but has to add back one for BooleanFormula,
LocatedBF / SrcSpanAnnBF
This commit also use the HsConDetails RecCon extension point to
capture the braces in a record constructor
- - - - -
2f6a5534 by Simon Jakobi at 2026-06-23T15:46:20+02:00
Add -dstable-core-dump-order for stable Core dump ordering (#27296)
The order of top-level bindings in Core dumps (-ddump-simpl etc.) is the
compiler's Unique-sensitive internal processing order, so an unrelated
upstream change can reorder them and defeat a textual diff of two dumps.
This adds an opt-in flag -dstable-core-dump-order that reorders the
top-level bindings of dumps routed through dumpPassResult into a stable,
Unique-independent order, so two dumps line up across rebuilds. See
Note [Stable Core dump order] in GHC.Core.Ppr for the sort key and its
rationale.
Adds tests T27296 (binders GHC emits in non-source order by default,
asserted to come out stably ordered under the flag) and T27296b (an
untidied -ddump-float-out dump pinning the ordering of the anonymous lvl
floats by literal value).
Co-Authored-By: Claude Opus 4.8 <noreply(a)anthropic.com>
- - - - -
141986e3 by mangoiv at 2026-06-24T15:51:14-04:00
compiler: refactor error reporting code for ExplicitLevelImports
Refactors error reporting code for ExplicitLevelImports to pass in a
RdrName and a GlobalReaderElt to be able to report errors that are
faithful to the source and to more precisely distinguish between names
that are in scope from different qualifications.
Fixes #27385 and #26616
- - - - -
aa7df6b6 by Simon Hengel at 2026-06-24T15:52:18-04:00
Set GHC_VERSION when calling custom pre-processors (see #25952)
(so that pre-processors can emit backwards compatible code)
- - - - -
a9e494f2 by Simon Hengel at 2026-06-24T15:54:08-04:00
Add a flag to control GHCi specific error hints (close #27409)
- - - - -
a805b2a2 by Simon Hengel at 2026-06-24T15:55:20-04:00
Reference correct package in error messages for reexported modules
(fixes #27417)
- - - - -
f235d183 by Simon Jakobi at 2026-06-25T05:51:18-04:00
Add explicit setBit/clearBit/complementBit for instance Bits Integer (#21176)
The default setBit, clearBit, and complementBit methods allocate
intermediate Integers per call. Define them explicitly via the new
integerSetBit[#], integerClearBit[#] and integerComplementBit[#], built
on the BigNat# primitives, which avoid those allocations. Allocation is not
eliminated entirely -- the negative (IN) cases would need in-place mutation,
which is left as future work.
The default methods constant-folded on literal arguments via the
integerOr/integerAnd/integerXor rules, which fold literal Integers of any
size. The explicit functions have no such rule, so they (their Word-argument
wrappers, and the Bits Integer methods) are marked INLINE to expose the
underlying primops to the simplifier; see Note [INLINE for constant folding
of bit operations]. This restores folding only on the small-int (IS) path --
large literal Integers (IP/IN) are no longer constant-folded, a minor
regression for that case. T8832 covers the IS-path folding.
The new golden-output test T21176 checks all three operations against the
default implementations across the sign/size boundaries, recording each
result plus its integerCheck validity. The base and ghc-bignum interface-
stability export goldens gain the new functions.
The main changelog entry lives in changelog.d under a new ghc-internal
section (renamed from ghc-prim).
CLC proposal: https://github.com/haskell/core-libraries-committee/issues/423
Co-Authored-By: Claude Opus 4.7 <noreply(a)anthropic.com>
- - - - -
202ed264 by Marc Scholten at 2026-06-25T05:52:21-04:00
haddock: use Text in documentation pipeline
This patch moves Haddock's documentation pipeline from String to Text
where the data is already textual. It avoids repeated conversions while
keeping the existing decoding behavior for invalid UTF-8 docstring
chunks.
The main changes are:
* Render and carry docstrings as Text in Haddock-facing paths.
* Use the Binary Text instance from GHC.Utils.Binary for Haddock
interface files, and bump the Haddock binary interface version.
* Add a FastString HTML instance so XHTML rendering avoids
intermediate String allocation.
* Keep HsDocStringChunk decoding lenient, matching the previous
unpackHDSC behavior on invalid UTF-8 input.
* Update the xhtml submodule to 3000.4.1.0, which contains the
apostrophe escaping fix used by the Haddock test output.
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot(a)users.noreply.github.com>
Co-authored-by: Claude Opus 4.5 <noreply(a)anthropic.com>
Assisted-by: Codex <codex(a)openai.com>
- - - - -
a72ff58f by mangoiv at 2026-06-25T05:53:07-04:00
compiler: rename ZonkAny to UnusedType and add pretty printing logic
ZonkAny is a hard to understand name for users who do not know how the
compiler works internally. Additionally, it is confusing that ZonkAny,
while being a concrete type *represents* a meta variable, espeically in
the compiler output.
This patch changes the name of ZonkAny to UnusedType which is closer to
its intended semantics and adds special pretty printing logic to display
this type in the same fashion the compiler displays meta variables in
other places, whenever they leak from the implementation to the user.
It also exports the type from ghc-internal:GHC.Internal.Types in order
to expose documentation.
Fixes #27390
Co-Authored-By: Sam Derbyshire <sam.derbyshire(a)gmail.com>
- - - - -
6813f002 by Simon Jakobi at 2026-06-26T04:51:47-04:00
Reg.Linear: drop Platform argument from most FR (FreeRegs) methods
The FR class has one instance per CPU architecture, so any
architecture-constant information its methods derived from the Platform
argument can instead be baked into the instance. This removes the now
needless Platform argument from frAllocateReg, frGetFreeRegs and
frReleaseReg.
frInitFreeRegs keeps its Platform argument: the initial allocatable set is
genuinely platform-dependent, see Note [Aarch64 Register x18 at Darwin and
Windows].
Fixes #26665
Co-Authored-By: Claude Opus 4.8 <noreply(a)anthropic.com>
- - - - -
3b2a9409 by Zubin Duggal at 2026-06-26T04:52:39-04:00
testsuite: Report fragile failures as skipped in JUnit output
- - - - -
27463426 by Rodrigo Mesquita at 2026-06-26T20:54:58-04:00
perf: Share Module in Iface Symbol Table
This commit modifies the structure of the serialized `SymbolTable Name`
to then re-use and share the `Module` (both on disk and in memory) across
all `Name`s from the same module.
The new structure looks like:
<total name count>
$modules.size
for (mod, names) in $modules:
$mod
$names.size
for table_ix, occ in $names
$table_ix
$occ
i.e. we put the module just once, followed by all names in that module.
When deserializing, we deserialize the module just once, and all the
following `Name`s are constructed with a pointer to that same decoded
`Module`.
In `hoogle-test`, we must use `DNameEnv` rather than `Map Name`,
otherwise the output fixities order was susceptible to changes in the
uniques assigned to each Names, which is not stable.
Fixes #27401
-------------------------
Metric Decrease:
InstanceMatching
LinkableUsage01
LinkableUsage02
hard_hole_fits
-------------------------
- - - - -
412f1675 by Simon Hengel at 2026-06-26T20:55:41-04:00
Rename `MCDiagnostic` to `InternalMCDiagnostic`
`MCDiagnostic` is meant to be used for compiler diagnostics.
Any code that creates `MCDiagnostic` directly, without going through
`GHC.Driver.Errors.printMessage`, sidesteps `-fdiagnostics-as-json` (see
e.g. !14616, !14475, !14492 !14548).
To avoid this in the future, this change more narrowly controls who
creates `MCDiagnostic` (see #24113).
- - - - -
6f212121 by Facundo Domínguez at 2026-06-26T20:56:27-04:00
Encapsulate options of occurAnalysePgm in a record
- - - - -
adfbb179 by Facundo Domínguez at 2026-06-26T20:56:27-04:00
Allow to configure the occurrence analyser to retain some dead bindings
This is needed by plugins that are the only consumers of a binding which
is otherwise unused in the program.
See Note [Controlling elimination of dead bindings in occurrence analysis]
added in this commit, or
https://gitlab.haskell.org/ghc/ghc/-/issues/27240 for more discussion.
- - - - -
c745b11f by Copilot at 2026-06-26T20:56:27-04:00
Address documentation feedback
- - - - -
2c2a4a2a by Copilot at 2026-06-26T20:56:27-04:00
Keep the imp_rules parameter of occurPgmAnalysePgm and add occ_opts to OccEnv
- - - - -
e2262b0e by Copilot at 2026-06-26T20:56:27-04:00
Strengthen T27240.hs with a binding that should be removed
- - - - -
5f9d9268 by Copilot at 2026-06-26T20:56:27-04:00
Move the reference #27240 to a related paragraph
- - - - -
d86d2644 by Simon Hengel at 2026-06-26T20:57:10-04:00
Remove deprecated flag `-ddump-json` (see #24113)
This was first deprecated in 9.10.1.
- - - - -
3b15ff03 by Simon Jakobi at 2026-06-27T18:48:34+02:00
Tweak mk_mod_usage_info
* Use O(log n) `elemModuleEnv` instead of O(n) `elem` to filter the
direct imports.
* Use `nonDetModuleEnvKeys` to avoid sorting the ent_map keys twice.
* Prepend the presumably shorter list when creating all_mods with
`(++)`. Actually this eliminates the `(++)` entirely, as it seems to
fuse with the `filter` expression.
As a result there is a tiny speed-up when generating the .hi-files for
modules with many imports.
None of the changes affect compilation determinism as the module list
is explicitly sorted to ensure a canonical order.
- - - - -
2d0fd154 by Alan Zimmerman at 2026-06-29T11:44:00-04:00
EPA: Remove LocatedC / SrcSpanAnnC
This is part of a cleanup of the zoo of
SrcSpanAnnXXX types for exact print annotations.
This one removes SrcSpanAnnC used for storing exact print annotations
for contexts. It replaces it with an explicit `HsContext` data type
that carries the annotations and the context.
So, replace
type HsContext pass = [LHsType pass]
with
type HsContext pass = HsContextDetails pass (LHsType pass)
data HsContextDetails pass arg
= HsContext
{ hsc_ext :: !(XHsContext pass)
, hsc_ctxt :: [arg]
}
| XHsContextDetails !(XXHsContextDetails pass)
We need the parameterised HsContextDetails because it is used both for
HsQual carrying 'LHsExpr p' and "normal" contexts carrying 'LHsType p'.
- - - - -
cca0d589 by Luite Stegeman at 2026-06-30T13:33:40-04:00
rts: handle large AP closures in compacting GC
The function update_fwd_large in the compacting GC could run into
an unexpected object with the following error:
internal error: update_fwd_large: unknown/strange object 24
Closure type 24 is the AP closure, which was not handled in
upd_fwd_large. This patch adds handling them.
fixes #27434
- - - - -
42935858 by Luite Stegeman at 2026-06-30T13:33:40-04:00
testsuite: use compacting_gc way instead of hardcoding +RTS -c
- - - - -
bf7b5ce6 by Alan Zimmerman at 2026-06-30T13:34:23-04:00
EPA: Remove LocatedLW from LStmtLR
HsDo already had its XDo extension point for an
AnnList, which also appeared in LocatedLW.
So we remove the redundant one and use the one inside HsDo
as originally intended.
Also delete LocatedLC/LocatedLS as they were unused
- - - - -
d7cfea49 by Recursion Ninja at 2026-06-30T21:37:12-04:00
Decoupling 'L.H.S' from 'GHC.Types.SourceText'
* Migrated 'IntegralLit' to 'L.H.S.Lit'.
* Migrated 'FractionalLit' to 'L.H.S.Lit'.
* Migrated 'StringLiteral' to 'L.H.S.Lit'.
* Added TTG extension points to the types above.
* Added nice export list to 'GHC.Hs.Lit'.
* Added 'rnOverLitVal' and 'tcOverLitVal' functions to 'GHC.Hs.Lit'.
* Added instance 'Anno (StringLiteral (GhcPass p)) = SrcSpanAnnN'
* Moved [Notes] about 'SourceText' from 'L.H.S.*' to 'GHC.*'.
* Removed all references to 'SourceText' from 'L.H.S'.
* Removed the trailing comma record field from 'StringLiteral'
* Renamed exported functions for nomenclature consistency.
* Deprecated the renamed functions
Fixes #26953
- - - - -
a1f2558b by Recursion Ninja at 2026-06-30T21:37:12-04:00
Monomorphising GHC pass parameters where appropriate
- - - - -
7bf9e3c5 by Teo Camarasu at 2026-06-30T21:38:03-04:00
Make Q abstract
This patch aims to clearly demarcate the internal and external interfaces
of Q.
In the past the `Quasi` typeclass was both part of the external,
public-facing interface, and was used to give the implementation of `Q`.
Now we separate out these two distinct roles. `Quasi` continues to exist
in the public interface, but we introduce a new `MetaHandlers` type,
which is equivalent to `Dict Quasi`.
`Q a` is now defined to be `MetaHandlers -> IO a`, and, crucially,
the constructor and the new `MetaHandlers` type are not exposed from the
public interface.
This gives us the ability to vary the interface on the GHC side without
forcing a breaking change on the `template-haskell` side.
Similarly `template-haskell` has more freedom to change the `Quasi`
typeclass without needing any changes in `lib:ghc`.
Implements https://github.com/ghc-proposals/ghc-proposals/pull/700
Resolves #27341
- - - - -
4262af36 by L0neGamer at 2026-06-30T21:38:56-04:00
generically defines mconcat in terms of internal type's Semigroup instance
add changelog entry
use simpler definition for mconcat
`nonEmpty` isn't available yet; inline branches in case
add test case
fixup generically defines mconcat in terms of internal type's Semigroup instance
add comment on Generically and deriving mishaps
swap mconcat to foldr version
add some strictness testing for mconcat
add to `base` changelog entry
- - - - -
e22ad997 by Cheng Shao at 2026-06-30T21:39:43-04:00
hadrian/rts: fix unregisterised build for gcc 15+
This patch fixes unregisterised build for gcc 15+:
- Pass -optc-Wno-error in hadrian when +werror enables -optc-Werror,
see added comment for details.
- For RTS functions that the codegen would emit calls, ensure their
real prototype is hidden when the header is included in .hc fies
(IN_STG_CODE), and the dummy prototype is provided to match the EFF_
convention.
In the future we should get rid of EFF_ (#14647) and remove these
hacks, but for now this patch makes unregisterised work again on newer
toolchains. Fixes #27404.
Co-authored-by: Codex <codex(a)openai.com>
- - - - -
3f00f234 by Cheng Shao at 2026-06-30T21:40:32-04:00
compiler: fix missing handling of CmmUnsafeForeignCall node in LayoutStack
This patch fixes missing handling of `CmmUnsafeForeignCall` middle
node in the `LayoutStack` pass.
Before proc-points splitting, this pass computes liveliness of local
registers, and spills those alive across a Cmm native call onto the
stack. It need to traverse all middle nodes in each block and check
whether a local register is an assignee, if so then the previous
mapping in `sm_regs` is invalidated and needs to be dropped. However,
it didn't handle `CmmUnsafeForeignCall` node which may also assign to
a local register. When proc-points splitting is enabled, this can
produce an invalid basic block that doesn't properly backup the
updated local register to the stack before doing a Cmm call, resulting
in completely invalid runtime behavior.
The patch also adds a `T27447` regression test. With no-TNTC or with
LLVM backend, without the fix the test case would output a stale
0x1111111111111111 value, instead of the expected 0x2222222222222222
output.
Fixes #27447.
Co-authored-by: Codex <codex(a)openai.com>
- - - - -
dc9d0dec by Cheng Shao at 2026-07-01T10:12:02+02:00
rts: add is-valid-utf8.c to .ubsan-suppressions
A minor one in `bytestring` that might surface when building with
+ubsan using clang.
- - - - -
f428a064 by Cheng Shao at 2026-07-01T10:12:02+02:00
hadrian: add support for building with AddressSanitizer
This patch adds a +asan flavour transformer to hadrian to build all
stage1+ C/C++ code with AddressBehaviorSanitizer. This is particularly
useful to catch potential out-of-bounds and use-after-free bugs in the
RTS codebase.
- - - - -
ab60a529 by Cheng Shao at 2026-07-01T10:12:02+02:00
ci: add ubsan+asan job
We now have a
`x86_64-linux-fedora43-quick-validate+debug_info+ubsan+asan`
validate/nightly job with both UBSan/ASan enabled. This is enabled in
full-ci pipelines as well as MR pipelines with `test-sanitizer` label.
- - - - -
6cf70fea by Cheng Shao at 2026-07-01T10:12:02+02:00
rts: add ASAN instrumentation to mblock allocator
- - - - -
795df8bf by Cheng Shao at 2026-07-01T10:12:02+02:00
rts: add ASAN instrumentation to mgroup allocator
- - - - -
2568e113 by Cheng Shao at 2026-07-01T10:12:02+02:00
rts: add ASAN instrumentation to block allocator
- - - - -
4bd5f662 by Cheng Shao at 2026-07-01T10:12:02+02:00
rts: add ASAN instrumentation to cap->pinned_object_empty
- - - - -
436967a1 by Cheng Shao at 2026-07-01T10:12:03+02:00
rts: add ASAN instrumentation to gc_thread->free_blocks
- - - - -
bb1aae7c by Cheng Shao at 2026-07-01T10:12:03+02:00
rts: add ASAN instrumentation to hash table free list
- - - - -
aaf76304 by Cheng Shao at 2026-07-01T10:12:03+02:00
rts: add ASAN instrumentation to per-Task InCall free list
- - - - -
357 changed files:
- .gitlab/generate-ci/gen_ci.hs
- .gitlab/jobs.yaml
- + changelog.d/26616
- + changelog.d/AbstractQ
- + changelog.d/T21176
- + changelog.d/add_can_drop_to_occurence_analyser
- changelog.d/config
- + changelog.d/fix-compacting-gc-ap-27434
- + changelog.d/fix-layout-stack-fcall
- + changelog.d/fix-unreg
- + changelog.d/generically-mconcat
- + changelog.d/interactive-error-hints
- + changelog.d/pp-set-ghc-version
- + changelog.d/reexported-module-errors
- + changelog.d/remove-ddump-json-flag
- + changelog.d/stable-core-dump-order-27296
- + changelog.d/unused-type
- compiler/GHC/Builtin/Names.hs
- compiler/GHC/Builtin/Types.hs
- compiler/GHC/Builtin/Utils.hs
- compiler/GHC/Cmm/LayoutStack.hs
- compiler/GHC/CmmToAsm/Reg/Linear.hs
- compiler/GHC/CmmToAsm/Reg/Linear/FreeRegs.hs
- compiler/GHC/CmmToAsm/Reg/Linear/JoinToTargets.hs
- compiler/GHC/CmmToAsm/Reg/Linear/X86.hs
- compiler/GHC/CmmToAsm/Reg/Linear/X86_64.hs
- compiler/GHC/CmmToAsm/X86/RegInfo.hs
- compiler/GHC/CmmToAsm/X86/Regs.hs
- compiler/GHC/Core/Lint.hs
- compiler/GHC/Core/Opt/OccurAnal.hs
- compiler/GHC/Core/Opt/Simplify.hs
- compiler/GHC/Core/Ppr.hs
- compiler/GHC/Core/SimpleOpt.hs
- compiler/GHC/Data/BooleanFormula.hs
- compiler/GHC/Data/IOEnv.hs
- compiler/GHC/Driver/Config.hs
- compiler/GHC/Driver/DynFlags.hs
- compiler/GHC/Driver/Errors.hs
- compiler/GHC/Driver/Flags.hs
- compiler/GHC/Driver/Main/Passes.hs
- compiler/GHC/Driver/Pipeline.hs
- compiler/GHC/Driver/Session.hs
- compiler/GHC/Hs.hs
- compiler/GHC/Hs/Binds.hs
- compiler/GHC/Hs/Decls.hs
- compiler/GHC/Hs/DocString.hs
- compiler/GHC/Hs/Dump.hs
- compiler/GHC/Hs/Expr.hs
- compiler/GHC/Hs/ImpExp.hs
- compiler/GHC/Hs/Instances.hs
- compiler/GHC/Hs/Lit.hs
- compiler/GHC/Hs/Pat.hs
- compiler/GHC/Hs/Stats.hs
- compiler/GHC/Hs/Type.hs
- compiler/GHC/Hs/Utils.hs
- compiler/GHC/HsToCore/Expr.hs
- compiler/GHC/HsToCore/Match.hs
- compiler/GHC/HsToCore/Match/Literal.hs
- compiler/GHC/HsToCore/Monad.hs
- compiler/GHC/HsToCore/Pmc/Desugar.hs
- compiler/GHC/HsToCore/Pmc/Solver/Types.hs
- compiler/GHC/HsToCore/Quote.hs
- compiler/GHC/HsToCore/Usage.hs
- compiler/GHC/Iface/Binary.hs
- compiler/GHC/Iface/Errors.hs
- compiler/GHC/Iface/Errors/Ppr.hs
- compiler/GHC/Iface/Errors/Types.hs
- compiler/GHC/Iface/Ext/Ast.hs
- compiler/GHC/Iface/Syntax.hs
- compiler/GHC/Iface/Type.hs
- compiler/GHC/Iface/Warnings.hs
- compiler/GHC/Parser.y
- compiler/GHC/Parser/Annotation.hs
- compiler/GHC/Parser/HaddockLex.x
- compiler/GHC/Parser/Lexer.x
- compiler/GHC/Parser/PostProcess.hs
- compiler/GHC/Parser/PostProcess/Haddock.hs
- compiler/GHC/Parser/Types.hs
- compiler/GHC/Rename/Bind.hs
- compiler/GHC/Rename/Env.hs
- compiler/GHC/Rename/Expr.hs
- compiler/GHC/Rename/HsType.hs
- compiler/GHC/Rename/Lit.hs
- compiler/GHC/Rename/Module.hs
- compiler/GHC/Rename/Names.hs
- compiler/GHC/Rename/Pat.hs
- compiler/GHC/Rename/Splice.hs
- compiler/GHC/Rename/Splice.hs-boot
- compiler/GHC/Rename/Unbound.hs
- compiler/GHC/Rename/Utils.hs
- compiler/GHC/SysTools/Tasks.hs
- compiler/GHC/SysTools/Terminal.hs
- compiler/GHC/Tc/Deriv.hs
- compiler/GHC/Tc/Deriv/Generate.hs
- compiler/GHC/Tc/Errors.hs
- compiler/GHC/Tc/Errors/Ppr.hs
- compiler/GHC/Tc/Errors/Types.hs
- compiler/GHC/Tc/Gen/App.hs
- compiler/GHC/Tc/Gen/Bind.hs
- compiler/GHC/Tc/Gen/Export.hs
- compiler/GHC/Tc/Gen/Head.hs
- compiler/GHC/Tc/Gen/HsType.hs
- compiler/GHC/Tc/Gen/Match.hs
- compiler/GHC/Tc/Gen/Sig.hs
- compiler/GHC/Tc/Gen/Splice.hs
- compiler/GHC/Tc/Gen/Splice.hs-boot
- compiler/GHC/Tc/Module.hs
- compiler/GHC/Tc/TyCl.hs
- compiler/GHC/Tc/TyCl/Utils.hs
- compiler/GHC/Tc/Types.hs
- compiler/GHC/Tc/Utils/Backpack.hs
- compiler/GHC/Tc/Utils/Env.hs
- compiler/GHC/Tc/Utils/Instantiate.hs
- compiler/GHC/Tc/Utils/Monad.hs
- compiler/GHC/Tc/Utils/TcMType.hs
- compiler/GHC/Tc/Utils/TcType.hs
- compiler/GHC/Tc/Zonk/Type.hs
- compiler/GHC/ThToHs.hs
- compiler/GHC/Types/Error.hs
- − compiler/GHC/Types/Error.hs-boot
- compiler/GHC/Types/Hint/Ppr.hs
- compiler/GHC/Types/Name/Reader.hs
- compiler/GHC/Types/PkgQual.hs
- compiler/GHC/Types/SourceError.hs
- compiler/GHC/Types/SourceText.hs
- compiler/GHC/Unit/Finder.hs
- compiler/GHC/Unit/Finder/Types.hs
- compiler/GHC/Unit/Module/Env.hs
- compiler/GHC/Unit/Module/Warnings.hs
- compiler/GHC/Unit/State.hs
- compiler/GHC/Utils/Error.hs
- compiler/GHC/Utils/Logger.hs
- compiler/GHC/Utils/Outputable.hs
- compiler/Language/Haskell/Syntax.hs
- compiler/Language/Haskell/Syntax/Binds.hs
- compiler/Language/Haskell/Syntax/Binds/InlinePragma.hs
- compiler/Language/Haskell/Syntax/Decls.hs
- compiler/Language/Haskell/Syntax/Decls/Foreign.hs
- compiler/Language/Haskell/Syntax/Expr.hs
- compiler/Language/Haskell/Syntax/Extension.hs
- compiler/Language/Haskell/Syntax/ImpExp.hs
- compiler/Language/Haskell/Syntax/Lit.hs
- compiler/Language/Haskell/Syntax/Type.hs
- docs/users_guide/debugging.rst
- docs/users_guide/ghci.rst
- docs/users_guide/phases.rst
- ghc/GHCi/UI.hs
- ghc/GHCi/UI/Exception.hs
- ghc/Main.hs
- hadrian/doc/flavours.md
- hadrian/src/Flavour.hs
- libraries/base/changelog.md
- libraries/base/src/GHC/Base.hs
- libraries/base/src/GHC/Exts.hs
- libraries/ghc-bignum/changelog.md
- libraries/ghc-experimental/src/GHC/PrimOps.hs
- libraries/ghc-internal/src/GHC/Internal/Bignum/Integer.hs
- libraries/ghc-internal/src/GHC/Internal/Bits.hs
- libraries/ghc-internal/src/GHC/Internal/Generics.hs
- libraries/ghc-internal/src/GHC/Internal/TH/Lib.hs
- libraries/ghc-internal/src/GHC/Internal/TH/Monad.hs
- libraries/ghc-internal/src/GHC/Internal/Types.hs
- libraries/ghci/GHCi/TH.hs
- libraries/template-haskell/Language/Haskell/TH/Syntax.hs
- libraries/xhtml
- rts/.ubsan-suppressions
- rts/Hash.c
- rts/Task.c
- rts/include/Stg.h
- + rts/include/rts/ASANUtils.h
- rts/include/rts/NonMoving.h
- rts/include/stg/MiscClosures.h
- rts/rts.cabal
- rts/sm/BlockAlloc.c
- rts/sm/Compact.c
- rts/sm/GCUtils.c
- rts/sm/MBlock.c
- rts/sm/Storage.c
- testsuite/driver/junit.py
- testsuite/driver/testglobals.py
- testsuite/driver/testlib.py
- testsuite/tests/annotations/should_fail/annfail03.stderr
- testsuite/tests/annotations/should_fail/annfail04.stderr
- testsuite/tests/annotations/should_fail/annfail06.stderr
- testsuite/tests/annotations/should_fail/annfail09.stderr
- + testsuite/tests/cmm/should_run/T27447.hs
- + testsuite/tests/cmm/should_run/T27447.stdout
- + testsuite/tests/cmm/should_run/T27447_cmm.cmm
- testsuite/tests/cmm/should_run/all.T
- testsuite/tests/driver/T16167.stderr
- − testsuite/tests/driver/T16167.stdout
- testsuite/tests/driver/all.T
- testsuite/tests/driver/json2.stderr
- − testsuite/tests/driver/json_dump.hs
- − testsuite/tests/driver/json_dump.stderr
- testsuite/tests/ffi/should_run/all.T
- + testsuite/tests/generics/T27245.hs
- + testsuite/tests/generics/T27245.stdout
- testsuite/tests/generics/all.T
- testsuite/tests/ghc-api/T25121_status.stdout
- + testsuite/tests/ghc-api/T27240.hs
- testsuite/tests/ghc-api/all.T
- testsuite/tests/ghc-api/annotations-literals/literals.stdout
- testsuite/tests/ghc-api/annotations-literals/parsed.hs
- testsuite/tests/ghc-api/exactprint/T22919.stderr
- testsuite/tests/ghc-api/exactprint/Test20239.stderr
- testsuite/tests/ghc-api/exactprint/ZeroWidthSemi.stderr
- testsuite/tests/ghci/prog-mhu002/prog-mhu002c.stdout
- testsuite/tests/ghci/scripts/ghci024.stdout
- testsuite/tests/ghci/scripts/ghci024.stdout-mingw32
- testsuite/tests/haddock/should_compile_flag_haddock/T17544.stderr
- testsuite/tests/haddock/should_compile_flag_haddock/T17544_kw.stderr
- testsuite/tests/haddock/should_compile_flag_haddock/T24221.stderr
- testsuite/tests/interface-stability/base-exports.stdout
- testsuite/tests/interface-stability/base-exports.stdout-javascript-unknown-ghcjs
- testsuite/tests/interface-stability/base-exports.stdout-mingw32
- testsuite/tests/interface-stability/ghc-bignum-exports.stdout
- testsuite/tests/interface-stability/ghc-prim-exports.stdout
- testsuite/tests/interface-stability/ghc-prim-exports.stdout-mingw32
- testsuite/tests/interface-stability/template-haskell-exports.stdout
- testsuite/tests/module/mod185.stderr
- + testsuite/tests/numeric/should_run/T21176.hs
- + testsuite/tests/numeric/should_run/T21176.stdout
- + testsuite/tests/numeric/should_run/T21176.stdout-ws-32
- testsuite/tests/numeric/should_run/all.T
- testsuite/tests/overloadedrecflds/should_compile/DRFPatSynExport.stdout
- + testsuite/tests/package/ImportReexport.hs
- + testsuite/tests/package/ImportReexport.stderr
- testsuite/tests/package/all.T
- testsuite/tests/parser/should_compile/DumpParsedAst.stderr
- testsuite/tests/parser/should_compile/DumpParsedAstComments.stderr
- testsuite/tests/parser/should_compile/DumpRenamedAst.stderr
- testsuite/tests/parser/should_compile/DumpSemis.stderr
- testsuite/tests/parser/should_compile/KindSigs.stderr
- testsuite/tests/parser/should_compile/T14189.stderr
- testsuite/tests/parser/should_compile/T15323.stderr
- testsuite/tests/parser/should_compile/T20452.stderr
- testsuite/tests/parser/should_compile/T20718.stderr
- testsuite/tests/parser/should_compile/T20718b.stderr
- testsuite/tests/parser/should_compile/T20846.stderr
- testsuite/tests/parser/should_compile/T23315/T23315.stderr
- testsuite/tests/perf/compiler/T11068.stdout
- testsuite/tests/pmcheck/should_compile/T12957.stderr
- testsuite/tests/printer/AnnotationNoListTuplePuns.stdout
- testsuite/tests/printer/T18791.stderr
- testsuite/tests/printer/Test10309.hs
- testsuite/tests/printer/Test20297.stdout
- testsuite/tests/printer/Test24533.stdout
- testsuite/tests/profiling/should_run/staticcallstack002.stdout
- testsuite/tests/quasiquotation/qq001/qq001.stderr
- testsuite/tests/quasiquotation/qq002/qq002.stderr
- testsuite/tests/quasiquotation/qq003/qq003.stderr
- testsuite/tests/quasiquotation/qq004/qq004.stderr
- testsuite/tests/quotes/LiftErrMsg.stderr
- testsuite/tests/quotes/LiftErrMsgDefer.stderr
- testsuite/tests/quotes/LiftErrMsgTyped.stderr
- testsuite/tests/quotes/T10384.stderr
- testsuite/tests/quotes/T5721.stderr
- testsuite/tests/quotes/TH_localname.stderr
- testsuite/tests/rename/should_compile/T1792_imports.stdout
- testsuite/tests/rename/should_compile/T18264.stdout
- testsuite/tests/rename/should_compile/T4239.stdout
- testsuite/tests/rts/T18623/all.T
- + testsuite/tests/rts/T27434.hs
- + testsuite/tests/rts/T27434.stdout
- testsuite/tests/rts/all.T
- testsuite/tests/showIface/DocsInHiFile1.stdout
- testsuite/tests/showIface/DocsInHiFileTH.stdout
- testsuite/tests/showIface/NoExportList.stdout
- testsuite/tests/simplCore/should_compile/Makefile
- testsuite/tests/simplCore/should_compile/T13156.stdout
- testsuite/tests/simplCore/should_compile/T26615.stderr
- + testsuite/tests/simplCore/should_compile/T27296.hs
- + testsuite/tests/simplCore/should_compile/T27296.stdout
- + testsuite/tests/simplCore/should_compile/T27296b.hs
- + testsuite/tests/simplCore/should_compile/T27296b.stdout
- testsuite/tests/simplCore/should_compile/T8832.hs
- testsuite/tests/simplCore/should_compile/T8832.stdout
- testsuite/tests/simplCore/should_compile/all.T
- testsuite/tests/splice-imports/SI03.stderr
- testsuite/tests/splice-imports/SI05.stderr
- testsuite/tests/splice-imports/SI08.stderr
- testsuite/tests/splice-imports/SI08_oneshot.stderr
- testsuite/tests/splice-imports/SI16.stderr
- testsuite/tests/splice-imports/SI18.stderr
- testsuite/tests/splice-imports/SI20.stderr
- testsuite/tests/splice-imports/SI25.stderr
- testsuite/tests/splice-imports/SI28.stderr
- testsuite/tests/splice-imports/SI29.stderr
- testsuite/tests/splice-imports/SI31.stderr
- testsuite/tests/splice-imports/SI36.stderr
- testsuite/tests/splice-imports/T26088.stderr
- testsuite/tests/splice-imports/T26090.stderr
- + testsuite/tests/splice-imports/T26616.hs
- + testsuite/tests/splice-imports/T26616.stderr
- testsuite/tests/splice-imports/all.T
- testsuite/tests/th/T16976z.stderr
- testsuite/tests/th/T17820a.stderr
- testsuite/tests/th/T17820b.stderr
- testsuite/tests/th/T17820c.stderr
- testsuite/tests/th/T17820d.stderr
- testsuite/tests/th/T17820e.stderr
- testsuite/tests/th/T21547.stderr
- testsuite/tests/th/T23829_hasty.stderr
- testsuite/tests/th/T23829_hasty_b.stderr
- testsuite/tests/th/T23829_tardy.ghc.stderr
- testsuite/tests/th/T26098_local.stderr
- testsuite/tests/th/T26098_quote.stderr
- testsuite/tests/th/T26098_splice.stderr
- testsuite/tests/th/T26099.stderr
- testsuite/tests/th/T26568.stderr
- testsuite/tests/th/T5795.stderr
- testsuite/tests/typecheck/should_compile/subsumption_sort_hole_fits.stderr
- testsuite/tests/typecheck/should_fail/T13292.stderr
- + testsuite/tests/typecheck/should_fail/T27390-explicit-kinds.stderr
- + testsuite/tests/typecheck/should_fail/T27390.hs
- + testsuite/tests/typecheck/should_fail/T27390.stderr
- + testsuite/tests/typecheck/should_fail/T27390a.hs
- testsuite/tests/typecheck/should_fail/all.T
- utils/check-exact/ExactPrint.hs
- utils/check-exact/Main.hs
- utils/check-exact/Preprocess.hs
- utils/check-exact/Utils.hs
- utils/haddock/haddock-api/src/Haddock.hs
- utils/haddock/haddock-api/src/Haddock/Backends/Hoogle.hs
- utils/haddock/haddock-api/src/Haddock/Backends/Hyperlinker.hs
- utils/haddock/haddock-api/src/Haddock/Backends/Hyperlinker/Parser.hs
- utils/haddock/haddock-api/src/Haddock/Backends/LaTeX.hs
- utils/haddock/haddock-api/src/Haddock/Backends/Xhtml.hs
- utils/haddock/haddock-api/src/Haddock/Backends/Xhtml/Decl.hs
- utils/haddock/haddock-api/src/Haddock/Backends/Xhtml/DocMarkup.hs
- utils/haddock/haddock-api/src/Haddock/Backends/Xhtml/Meta.hs
- utils/haddock/haddock-api/src/Haddock/Backends/Xhtml/Names.hs
- utils/haddock/haddock-api/src/Haddock/Backends/Xhtml/Utils.hs
- utils/haddock/haddock-api/src/Haddock/Convert.hs
- utils/haddock/haddock-api/src/Haddock/Doc.hs
- utils/haddock/haddock-api/src/Haddock/GhcUtils.hs
- utils/haddock/haddock-api/src/Haddock/Interface/AttachInstances.hs
- utils/haddock/haddock-api/src/Haddock/Interface/Create.hs
- utils/haddock/haddock-api/src/Haddock/Interface/Json.hs
- utils/haddock/haddock-api/src/Haddock/Interface/LexParseRn.hs
- utils/haddock/haddock-api/src/Haddock/Interface/ParseModuleHeader.hs
- utils/haddock/haddock-api/src/Haddock/Interface/Rename.hs
- utils/haddock/haddock-api/src/Haddock/Interface/RenameType.hs
- utils/haddock/haddock-api/src/Haddock/InterfaceFile.hs
- utils/haddock/haddock-api/src/Haddock/Options.hs
- utils/haddock/haddock-api/src/Haddock/Parser.hs
- utils/haddock/haddock-api/src/Haddock/Types.hs
- utils/haddock/haddock-api/src/Haddock/Utils/Json.hs
- utils/haddock/haddock-api/src/Haddock/Utils/Json/Parser.hs
- utils/haddock/haddock-api/src/Haddock/Utils/Json/Types.hs
- utils/haddock/haddock-library/src/Documentation/Haddock/Doc.hs
- utils/haddock/haddock-library/src/Documentation/Haddock/Markup.hs
- utils/haddock/haddock-library/src/Documentation/Haddock/Parser.hs
- utils/haddock/haddock-library/src/Documentation/Haddock/Parser/Util.hs
- utils/haddock/haddock-library/src/Documentation/Haddock/Types.hs
- utils/haddock/haddock-library/test/Documentation/Haddock/ParserSpec.hs
The diff was not included because it is too large.
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/73c0b8976368de96438830ebfd67e0…
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[Git][ghc/ghc][wip/jeltsch/textual-bytecode-output] Remove output of instructions and bitmaps
by Wolfgang Jeltsch (＠jeltsch) 01 Jul '26
by Wolfgang Jeltsch (＠jeltsch) 01 Jul '26
01 Jul '26
Wolfgang Jeltsch pushed to branch wip/jeltsch/textual-bytecode-output at Glasgow Haskell Compiler / GHC
Commits:
e3a7a15d by Wolfgang Jeltsch at 2026-07-01T16:26:52+03:00
Remove output of instructions and bitmaps
- - - - -
2 changed files:
- compiler/GHC/ByteCode/Show.hs
- libraries/ghci/GHCi/ResolvedBCO.hs
Changes:
=====================================
compiler/GHC/ByteCode/Show.hs
=====================================
@@ -15,7 +15,7 @@ import Data.Function (($), id, (.))
import Data.Tuple (fst, snd, uncurry)
import Data.Bool (Bool, otherwise, not, (&&))
import Data.Int (Int)
-import Data.Word (Word, Word16)
+import Data.Word (Word)
import Data.Maybe (Maybe, maybe)
import Data.Either (Either, either)
import Data.List (length, (++), map, zipWith, take, drop, replicate)
@@ -24,12 +24,10 @@ import Data.ByteString (ByteString, unpack)
import Data.ByteString.Short (ShortByteString)
import Data.IntMap (IntMap)
import Data.IntMap qualified as IntMap (toList)
-import Data.Array.IArray (IArray, bounds, indices, elems)
-import Data.Array.Unboxed (UArray)
+import Data.Array (bounds, indices, elems)
import Numeric (showHex)
import Text.Show (show)
import System.IO (IO, FilePath)
-import Foreign.Storable (Storable)
import GHC.Data.Strict qualified as Strict (Maybe, maybe)
import GHC.Data.FastString (unpackFS)
import GHC.Data.FlatBag (FlatBag, elemsFlatBag)
@@ -78,7 +76,6 @@ import GHC.ByteCode.Breakpoints
import GHC.ByteCode.Binary (OnDiskModuleByteCode (..))
import GHC.ByteCode.Serialize (readOnDiskModuleByteCode)
import GHC.Driver.Env.Types (HscEnv)
-import GHCi.ResolvedBCO (BCOByteArray, fromBCOByteArray)
import GHCi.FFI (FFIType)
import GHCi.Message (ConInfoTable (..))
@@ -132,8 +129,6 @@ pprByteCodeObject currentModule byteCodeObject = case byteCodeObject of
-> entry (text "ordinary object" <+> ppr unlinkedBCOName <> text ":") $
vcat [
pprArity $ unlinkedBCOArity,
- pprInstructions $ unlinkedBCOInstrs,
- pprBitmap $ unlinkedBCOBitmap,
pprLiterals currentModule $ unlinkedBCOLits,
pprPointers currentModule $ unlinkedBCOPtrs
]
@@ -155,14 +150,6 @@ pprByteCodeObject currentModule byteCodeObject = case byteCodeObject of
pprArity :: Int -> SDoc
pprArity = entry (text "arity:") . ppr
--- | […]
-pprInstructions :: BCOByteArray Word16 -> SDoc
-pprInstructions = entry (text "instructions:") . pprBCOByteArray
-
--- | […]
-pprBitmap :: BCOByteArray Word -> SDoc
-pprBitmap = entry (text "bitmap:") . pprBCOByteArray
-
-- | […]
pprDataConstructorName :: Name -> SDoc
pprDataConstructorName = entry (text "data constructor name:") . ppr
@@ -530,11 +517,6 @@ pprObjectFileContent ix = entry (text "file" <+> ppr ix <> text ":") .
pprByteString :: ByteString -> SDoc
pprByteString = pprFixedSizeNaturalList . unpack
--- | […]
-pprBCOByteArray :: (Integral a, FiniteBits a, Storable a, IArray UArray a) =>
- BCOByteArray a -> SDoc
-pprBCOByteArray = pprFixedSizeNaturalList . elems . fromBCOByteArray
-
-- | […]
pprFixedSizeNaturalList :: (Integral a, FiniteBits a) => [a] -> SDoc
pprFixedSizeNaturalList [] = text "<empty>"
=====================================
libraries/ghci/GHCi/ResolvedBCO.hs
=====================================
@@ -7,7 +7,6 @@ module GHCi.ResolvedBCO
, isLittleEndian
, BCOByteArray(..)
, mkBCOByteArray
- , fromBCOByteArray
) where
#include "MachDeps.h"
@@ -21,6 +20,7 @@ import GHCi.BreakArray
import Control.Monad
import Data.Array.Base (foldrArray, listArray)
import Data.ByteString.Builder.Extra
+import Foreign.Storable
#endif
import Data.Binary (Binary(..))
@@ -32,7 +32,6 @@ import GHC.Generics
import GHC.Exts
import Data.Array.Base (UArray(..))
-import Foreign.Storable
import qualified GHC.Exts.Heap as Heap
#include "MachDeps.h"
@@ -92,11 +91,13 @@ data BCOByteArray a
getBCOByteArray :: !ByteArray#
}
+#if SIZEOF_HSWORD == 4
fromBCOByteArray :: forall a . Storable a => BCOByteArray a -> UArray Int a
fromBCOByteArray (BCOByteArray ba#) = UArray 0 (n - 1) n ba#
where
len# = sizeofByteArray# ba#
n = (I# len#) `div` sizeOf (undefined :: a)
+#endif
mkBCOByteArray :: UArray Int a -> BCOByteArray a
mkBCOByteArray (UArray _ _ _ arr) = BCOByteArray arr
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/e3a7a15dd98945796f7260c0b18ed74…
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View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/e3a7a15dd98945796f7260c0b18ed74…
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