Duncan Coutts pushed to branch wip/io-manager-deadlock-detection at Glasgow Haskell Compiler / GHC

Commits:

• b9160962
  by Simon Jakobi at 2026-08-20T14:57:52-04:00

  testsuite: Show baseline sample count and range in perf failures
  
  A perf baseline is the mean of all samples recorded for a commit, and
  it prints as a single number, hiding how far the samples spread. When
  the spread is wide, this can indicate an unstable metric that isn't
  actually useful as a signal for the perf tests.
  For example, in #27602, T27336's peak_megabytes_allocated baseline
  showed as 757 when the underlying samples were 605 and 909.
  
  When the baseline is averaged from more than one sample, say so in the
  failure output: the one-line stat-failure reason shows the sample
  range, and the detail block lists the raw samples. Single-sample
  baselines print exactly as before.
  
  Context: #27602
  
  Assisted-by: Claude Fable 5
  

• a4979877
  by Simon Jakobi at 2026-08-20T14:57:52-04:00

  testsuite: Fold Baseline into CommitMetric
  
  A Baseline was just a CommitMetric plus the commit it came from, built
  by copying fields across. Since get_commit_metric already knows that
  commit, record it on CommitMetric itself and drop Baseline. This also
  collapses both branches of find_baseline into plain returns.
  
  Assisted-by: Claude Fable 5
  

• 99fb8d68
  by Simon Jakobi at 2026-08-20T14:57:52-04:00

  ci: Clarify comment on pushing perf notes after failures
  
  Context: #27602
  
  Assisted-by: Claude Fable 5
  

• 2ca87972
  by Alan Zimmerman at 2026-08-20T14:58:36-04:00

  EPA: Remove LocatedBC / SrcSpanBF
  
  The custom annotations are now in the BooleanFormula TTG extension
  points, so LBooleanFormula can now use the standard LocatedA.
  

• d2bc32aa
  by Simon Peyton Jones at 2026-08-21T12:59:26-04:00

  Better handling of serialisation of wired-in names
  
  Fixes #27501
  

• d2795ffc
  by Alan Zimmerman at 2026-08-21T13:00:05-04:00

  EPA: Remove NoEpTok/NoEpUniTok, using an unhelpful SrcSpan instead
  
  Also introduce helper functions noEpTok and noEpUniTok to serve
  as simple replacements in code inserting an token annotation without
  location information.
  

• b5d29ab8
  by Brandon Chinn at 2026-08-25T18:42:08-04:00

  Add Data.RealFloat and Infinity/NegInfinity/NaN pattern synonyms (#26961)
  

• e60eb3bc
  by Andreas Klebinger at 2026-08-25T18:42:59-04:00

  rts linker: Fix pointer arithmetic issue in flushInstructionCacheRISCV64
  
  We accidentally operated over `uint64_t*` when we should use `uint8_t`.
  
  Fixes #27569
  

• e9bbe8f9
  by Andreas Klebinger at 2026-08-26T15:09:23-04:00

  cmm dumps: Add machop width info with -dppr-debug for infix ops.
  

• 86e3a9d8
  by Andreas Klebinger at 2026-08-26T15:09:24-04:00

  CmmLint: Check for unsupported MachOp widths
  
  machOpArgReps now maps MachOp + Width to a list of supported
  argument widths or Nothing if the given operation is not supported
  at the given width.
  
  This allows us to check for nonsensical combinations like FloatToInt
  at Word16.
  
  Similarly we now check that every address is actually wordwidth.
  

• 13781cca
  by Andreas Klebinger at 2026-08-26T15:09:24-04:00

  arm64 ncg: The big subword truncation fix.
  
  A set of slightly related fixes to arm subword handling:
  
  Bitmask immediates:
  
  Don't produce overflowing assembly literals.
  There is still another bug here that causes us to miss some valid
  literals but we will fix that later.
  
  Improve subword truncation handling:
  
  We now use a small set of helpers to truncate `Register` values rather
  than truncating immediate `Reg` values which greatly simplifies the code
  structure. This fixes a great many bugs to do with sign/zero extending subwords
  or the lack thereof.
  
  We now establish the invariant that subword values are zero-extended at
  every site at which they come into "scope" of the ncg, and rely on the
  invariant throughout rather than pessimistically inserting redundant
  extensions in a hodgepodge manner at the use sites of these values.
  
  This fixes at least the bugs described in issues #27533, #27430
   #27537, #27538, #27539, and #27550. But likely more bugs yet not
  found.
  
  Subword ffi results:
  Apply truncations when calling functions returning
  subword values.
  
  genCondJump:
  Don't sign extend signed values in the input register as
  it might map to a local variable, corrupting the value stored within.
  
  Fix subword store/load instructions.:
  
  We used to read those at 32bit width even for smaller values possibly
  resulting in invalid memory access. Now we construct the suffix for
  subword variants based on the instruction format for these.
  

• d8fa5d7c
  by Andreas Klebinger at 2026-08-26T15:09:24-04:00

  arm64 ncg: Fix MO_V_Broadcast for non-literals.
  
  We now use OpReg instead of OpScalarAsVec as required since we broadcast a gp register.
  
  Also adds a test. Fixes #27565.
  

• 94822c95
  by Andreas Klebinger at 2026-08-26T15:09:24-04:00

  Add some test cases covering bugs in the arm ncg.
  
  * Test for #27430 (subword ffi results)
  * #27537 - subword conversions
  * #27538 - subwords used in conditional
  * #27533 - single byte read
  

• dd1ba88a
  by Andreas Klebinger at 2026-08-26T15:09:24-04:00

  cmmLint: Lint against MO_FS_Truncate subword use.
  

• fd22f71e
  by Zubin Duggal at 2026-08-26T15:10:20-04:00

  ghc-internal: annotateSTM should use catchSTM# rather than catch#
  
  A catch# frame inside a transaction breaks retry and async exception
  delivery.
  
  Fixes #27657
  

• bb324171
  by Rodrigo Mesquita at 2026-08-26T15:10:59-04:00

  rts: refactor to reduce THREADED_RTS in MSG_UPD_TSO_FLAGS
  
  - No behavior change in this commit (well, a small optimization here
    makes us do less work if the target TSO owned by the curr. capability)
  - Move all THREADED_RTS CPP needed into `updThreadFlag`
  - Merge MSG_SET_TSO_FLAGS and MSG_UNSET_TSO_FLAGS into MSG_UPD_TSO_FLAGS
    plus a `set` bool field in the MessageUpdTSOFlag struct
  
  Towards #27729
  

• ed99b7b7
  by Rodrigo Mesquita at 2026-08-26T15:10:59-04:00

  rts: Fix race condition in MSG_UPD_TSO_FLAGS execution
  
  The code for processing the MSG_UPD_TSO_FLAGS message was not taking
  into consideration that the TSO's owner might have moved in between that
  capability receiving the message (since it was its previous owner) and
  starting to process its inbox (a point at which it was no longer the
  owner)
  
  Added Note [TSO owner may change in between Msg being sent and received]
  to explain this race and the pattern used to fix this, where we just
  forward the message to the new owner.
  
  Fixes #27729
  

• cd653714
  by Alan Zimmerman at 2026-08-26T15:11:49-04:00

  EPA: Uses Parsers.parseModule for exactprint tests
  
  Parsers.parseModule is the advertised way to parse for use for exact
  printing in the ghc-exactprint library. This commit updates the GHC
  exact print testing to use it.
  
  This requires moving the comment balancing that was occurring
  only in the test path into the advertising parser path, so it moves
  from Transforms.hs to Utils.hs.
  
  Also update the comment adding to honour trailing annotations
  

• d1d01fa5
  by Wolfgang Jeltsch at 2026-08-27T13:17:59+03:00

  Add `rethrowSTM` and improve STM-related documentation
  
  Adding `rethrowSTM` resolves #26758.
  
  The implementation of `rethrowSTM` is completely analogous to the one of
  `rethrowIO`.
  
  The following is established for the documentation of `throwSTM` and
  `catchSTM`:
  
    * Both operations are directly described as analogs of their `IO`
      counterparts.
  
    * There is no reference to `throw` in the documentation of `throwSTM`,
      because, although such a reference is great in the documentation of
      `throwIO`, it is somewhat out of place in the documentation of
      `throwSTM`.
  
    * Instead of repeating part of `throwIO`’s documentation, the
      documentation of `throwSTM` just recommends using `throwSTM` instead
      of `throw` and references the corresponding arguments in the
      documentation of `throwIO`.
  

• 06fde293
  by fendor at 2026-08-28T06:06:44-04:00

  GHCi: Fix order of `PackageDBFlag`s for interactive home unit
  
  `PackageDBFlag`s are stored in reverse order of cli specification.
  When sorting the `PackageDBFlag`s by longest common prefix, we need thus
  to reverse the package db stacks before calculating the prefix.
  We make sure to reverse the package db stack for the interactive home
  unit to uphold that later specified package dbs overwrite earlier ones.
  
  Resolved and adds regression test for #27640
  

• 024c4d04
  by fendor at 2026-08-28T06:07:23-04:00

  Reuse the UnitIndexCache after initialising multiple home units
  

• 55326fa0
  by Alan Zimmerman at 2026-08-28T06:08:03-04:00

  EPA: Some Haddock processing tweaks
  
  These changes to the Haddock postprocessing should not change
  behaviour, but just bring it more closely in line with the
  original, changed at 44309cd377f
  
  And add some haddock exactprint tests to show they work.
  

• b3ddee95
  by Andreas Klebinger at 2026-08-28T13:57:46-04:00

  hadrian: Deprecate quickest flavour.
  
  It was more of a trap for new users than actually beneficial so we
  deprecate it and suggest quick+no_dynamic_libs to users instead.
  

• a1d81390
  by Andreas Klebinger at 2026-08-28T13:58:37-04:00

  cmm: Always favour entry block during block deduplication.
  
  We now always keep the first block in the CmmGraph. This way we avoid
  the need to update the entry info table.
  
  Failing to do so caused #27722.
  
  Fixes #27722.
  

• 5bd65f00
  by Andreas Klebinger at 2026-08-28T13:59:16-04:00

  test: FamAppCachePerf - Only collect bytes allocated. Fixes 27747
  

• ced53ce6
  by mangoiv at 2026-08-29T07:15:24-04:00

  nightlies: output yaml to file only
  
  Previously we would just output the metadata to stdout
  which risks that it's clobbered by incidental debugt output.
  We now output to file only.
  
  Fixes #27511
  

• 578bd185
  by Andreas Klebinger at 2026-08-29T07:16:05-04:00

  Specialise: Stop looping on recursive dictionaries in interestingDict
  
  interestingDict now doesn't look through loopbreaker unfoldings.
  Doing so would cause infinite loops on certain dictionaries.
  
  Fixes #27705.
  

• 056a2922
  by Duncan Coutts at 2026-08-29T15:05:53+01:00

  Make signal handling be a responsibility of the I/O manager(s)
  
  Previously it was scattered between I/O managers and the scheduler, and
  especially the scheduler's deadlock detection.
  
  Previously the scheduler would poll for pending signals each iteration
  of the scheduler loop. The scheduler also had some hairy signal
  functionality in the deadlock detection: in the non-threaded RTS (only)
  if there were still no threads running after deadlock detection then it
  would block waiting for signals.
  
  But signals can and (in my opinion) should be thought of as just a funny
  kind of I/O, and thus should be a responsibility of the I/O manager.
  
  So now we have the I/O managers poll for signals when they are polling
  for I/O completion (and removing the separate poll in the scheduler).
  And when I/O managers block waiting for I/O then they now also start
  signal handlers if they get interrupted by a signal. Crucially, if there
  is no pending I/O or timers, the awaitCompletedTimeoutsOrIO will still
  block waiting for signals.
  
  This patch puts us into an intermediate state: it temporarily breaks
  deadlock detection in the non-threaded RTS. The waiting on I/O currently
  happens before deadlock detection. This means we'll now wait forever on
  signals before doing deadlock detection. We need to move waiting after
  deadlock detection. We'll do that in a later patch.
  

• eaa702ad
  by Duncan Coutts at 2026-08-29T15:05:54+01:00

  Clean up the RTS internal signal handling API
  
  Now that the I/O manager is responsible for signals, we can simplify the
  API we present for signal handling.
  
  We now just need startPendingSignalHandlers, which is called from the
  I/O managers. We can get rid of awaitUserSignals. We also don't need
  RtsSignals.h to re-export the platform-specific posix/Signals.h or
  win32/ConsoleHandler.h
  
  We can also hide more of the implementation of signals. Less has to be
  exposed in posix/Signals.h or win32/ConsoleHandler.h. Indeed,
  posix/Signals.h becomes empty and we remove it. Partly this is because
  we don't need inline functions (or macros) in the interface.
  
  Also remove signal_handlers from RTS ABI exported symbols list. It does
  not appear to have any users in the core libs, and its really an
  internal implementation detail. It should not be exposed unless it's
  really necessary.
  

• a86a15ba
  by Duncan Coutts at 2026-08-29T15:05:54+01:00

  In the scheduler, move I/O blocking after deadlock detection
  
  To make deadlock detection effective in the non-threaded RTS when there
  are deadlocked threads and other unrelated threads waiting on I/O, we
  need to arrange to do deadlock detection before we block in scheduler
  to wait on I/O.
  
  The solution is to:
  
  1. adjust scheduleFindWork, which runs before deadlock detection, to
     only poll for I/O and not block; and
  2. add a step after deadlock detection to wait on I/O if there are
     still no threads to run (and there's any I/O or timeouts outstanding)
  
  The scheduleCheckBlockedThreads is now so simple that it made more sense
  to inline it into scheduleFindWork.
  

• 8d5a7123
  by Duncan Coutts at 2026-08-29T15:05:54+01:00

  Remove bogus anyPendingTimeoutsOrIO guard from scheduleDetectDeadlock
  
  The deadlock detection was only invoked if both of these conditions
  hold:
  1. the run queue is empty
  2. there is no pending I/O or timeouts
  
  The second condition is unnecessary. The deadlock detection mechanism
  can find deadlocks even if there are other threads waiting on I/O or
  timers. Having this extra condition means that we fail to detect
  blocked threads if there are any threads waiting on I/O or timers.
  
  Part of fixing issue #26408
  

• 02e01659
  by Duncan Coutts at 2026-08-29T15:05:54+01:00

  Don't consider pending I/O for early context switch optimisation
  
  Context switches are normally initiated by the timer signal. If however
  the user specifies "context switch as often as possible", with +RTS -C0
  then the scheduler arranges for an early context switch (when it's just
  about to run a Haskell thread).
  
  Context switching very often is expensive, so as an optimisation there
  cases where we do not arrange an early context switch:
  1. if there's no other threads to run
  2. if there is no pending I/O or timers
  
  This patch eliminates case 2, leaving only case 1.
  
  The rationale is as follows. The use of this was inconsistent across
  platforms and threaded/non-threaded RTS ways. It only worked on the
  non-threaded RTS and on Windows only worked for the win32-legacy I/O
  manager. On all other combinations anyPendingTimeoutsOrIO would always
  return false. The fact that nobody noticed and complained about this
  inconsistency suggests that the feature is not relied upon.
  
  If however it turns out that applications do rely on this, then the
  proper thing to do is not to restore this check, but to add a new I/O
  manager hint function that returns if there is any pending events that
  are likely to happen *soon*: for example timeouts expiring within one
  timeslice, or I/O waits on things likely to complete soon like disk I/O,
  but not for example socket/pipe I/O.
  
  The motivation to avoid this use of anyPendingTimeoutsOrIO is to
  allow us to eliminate anyPendingTimeoutsOrIO entirely. All other uses
  of this are just guards on {await,poll}CompletedTimeoutsOrIO and
  the guards can safely be folded into those functions. This will better
  cope with some I/O managers having no proper implementation of
  anyPendingTimeoutsOrIO.
  
  Ultimately this will let us simplify the scheduler which currently has
  to have special #ifdef mingw32_HOST_OS cases to cope with the lack of a
  working anyPendingTimeoutsOrIO for some Windows I/O managers
  

• 03034950
  by Duncan Coutts at 2026-08-29T15:05:54+01:00

  Remove anyPendingTimeoutsOrIO guarding {poll,await}CompletedTimeoutsOrIO
  
  Previously the API of the I/O manager used a two step process: check
  anyPendingTimeoutsOrIO and then call {poll,await}CompletedTimeoutsOrIO.
  This was primarily there as a performance thing, to cheaply check if we
  need to do anything.
  
  And then because anyPendingTimeoutsOrIO existed, it was used for other
  things too. We have now eliminated the other uses, and are just left
  with the performance pattern.
  
  But this was problematic because not all I/O managers correctly
  implement anyPendingTimeoutsOrIO (specifically the win32 ones), and now
  that we also make I/O managers responsible for signals then we need to
  poll/await even if there is no pending I/O or timeouts. If there is no
  pending I/O or timeouts then await needs to degenerate to just waiting
  forever for any signals.
  

• 87f4d822
  by Duncan Coutts at 2026-08-29T15:05:54+01:00

  Remove anyPendingTimeoutsOrIO, it is no longer used
  
  And this avoids the problems arising from the win32 I/O managers having
  had a bogus implementation.
  

• e7b3d491
  by Duncan Coutts at 2026-08-29T15:05:54+01:00

  Remove second scheduler call to awaitCompletedTimeoutsOrIO
  
  Previously awaitCompletedTimeoutsOrIO was called both before and after
  deadlock detection in the scheduler. The reason for that was that the
  win32 I/O managers had a bogus implementation of anyPendingTimeoutsOrIO
  and this was used to guard the call of awaitCompletedTimeoutsOrIO prior
  to deadlock detection. This meant the first call site was never actually
  called when using the win32 I/O managers. This was the reason for the
  second call: the first one was never used. What a mess.
  
  So now we have a simple design in the scheduler:
  1. poll for completed I/O, timers or signals
  2. if no runnable threads: do deadlock detection
  3. if still no runnable threads: block waiting for I/O, timers or
     signals.
  

• 9380d96d
  by Duncan Coutts at 2026-08-29T15:05:54+01:00

  Lift emptyRunQueue guard out of scheduleDetectDeadlock
  
  this improved the clarity of the logic when reading the scheduler code.
  

• 351a494e
  by Duncan Coutts at 2026-08-29T15:05:54+01:00

  Make non-threaded deadlock detection also rely on idle GC
  
  Only do deadlock detection GC when idle GC kicks in. This also relies on
  using wakeUpRts, so now do this unconditionally. Previously wakeUpRts
  was for the threaded rts only.
  

• 04079545
  by Duncan Coutts at 2026-08-29T15:05:54+01:00

  Enable idle GC by default on non-threaded RTS
  
  The behaviour is now uniform between the threaded and non-threaded RTS
  ways. The deadlock detection now relies on idle GC for both threaded
  and non-threaded ways. Previously deadlock detection did not rely on
  idle GC for the non-threaded way.
  
  Also tweak test T7275 to account for idle GC. This test's output is
  sensitive to the number of major GCs run. Since this commit enables idle
  GC for the non-threaded RTS, for this test that increases the number of
  major GCs, since the test program is frequently idle for more than 300ms.
  

• 64c86af4
  by Duncan Coutts at 2026-08-29T15:05:54+01:00

  Fix state of idle GC control vars with +RTS -V0
  
  Currently when the user uses +RTS -I0, then doIdleGC is set to false.
  But if the master tick interval -V is set to 0 then the idleGCDelayTime
  was being set to 0 but doIdleGC was not being set to false, which is
  inconsistent, and almost certainly buggy.
  

• e420e5f9
  by Duncan Coutts at 2026-08-29T15:05:54+01:00

  Add a long Note [Deadlock detection]
  
  It describes the historical and modern designs and their trade-offs.
  
  The point is we've now unified the code for deadlock detection between
  the threaded and non-threaded ways, by changing the non-threaded to
  follow the same design as the threaded.
  

• 0f247bde
  by Duncan Coutts at 2026-08-29T15:05:54+01:00

  Add a test for deadlock detection, issue #26408
  

• 5870d43d
  by Duncan Coutts at 2026-08-29T15:05:54+01:00

  Update the user guide with the revised idle GC behaviour
  
  i.e. it's now not just for the threaded RTS, but general.
  
  Also document the fact that disabling idle GC also disables deadlock
  detection.
  
  And add a changelog entry.
  

• e2248e80
  by Duncan Coutts at 2026-08-29T15:24:34+01:00

  DEBUG: attempts to debug wasm poll failures
  

161 changed files:

• .gitlab-ci.yml
• .gitlab/ci.sh
• .gitlab/rel_eng/mk-ghcup-metadata/mk_ghcup_metadata.py
• changelog.d/T27202
• + changelog.d/T27657
• + changelog.d/T27705
• + changelog.d/T27722-cbe-entry-block.md
• + changelog.d/arm_ncg_fixes_T27430
• + changelog.d/idle-gc-and-deadlock-detection
• + changelog.d/rethrow-stm
• changelog.d/unit-index
• compiler/GHC/Builtin.hs
• compiler/GHC/Cmm/CommonBlockElim.hs
• compiler/GHC/Cmm/Expr.hs
• compiler/GHC/Cmm/Lint.hs
• compiler/GHC/Cmm/MachOp.hs
• compiler/GHC/Cmm/Parser.y
• compiler/GHC/CmmToAsm/AArch64/CodeGen.hs
• compiler/GHC/CmmToAsm/AArch64/Instr.hs
• compiler/GHC/CmmToAsm/AArch64/Ppr.hs
• compiler/GHC/Core/Opt/Specialise.hs
• compiler/GHC/Data/BooleanFormula.hs
• compiler/GHC/Driver/Session/Units.hs
• compiler/GHC/Hs.hs
• compiler/GHC/Hs/Dump.hs
• compiler/GHC/Hs/Utils.hs
• compiler/GHC/Iface/Binary.hs
• compiler/GHC/Iface/Ext/Ast.hs
• compiler/GHC/Iface/Syntax.hs
• compiler/GHC/IfaceToCore.hs
• compiler/GHC/Parser.y
• compiler/GHC/Parser/Annotation.hs
• compiler/GHC/Parser/PostProcess.hs
• compiler/GHC/Parser/PostProcess/Haddock.hs
• docs/users_guide/runtime_control.rst
• ghc/GHCi/UI.hs
• hadrian/README.md
• hadrian/doc/cross-compile.md
• hadrian/doc/flavours.md
• hadrian/doc/make.md
• hadrian/doc/windows.md
• hadrian/hadrian.cabal
• hadrian/src/CommandLine.hs
• hadrian/src/Flavour.hs
• hadrian/src/Settings.hs
• − hadrian/src/Settings/Flavours/Quickest.hs
• libraries/base/base.cabal.in
• libraries/base/changelog.md
• + libraries/base/src/Data/RealFloat.hs
• libraries/base/src/GHC/Conc.hs
• libraries/ghc-internal/src/GHC/Internal/STM.hs
• rts/CloneStack.c
• rts/IOManager.c
• rts/IOManager.h
• rts/Interpreter.c
• rts/Linker.c
• rts/Messages.c
• rts/RtsFlags.c
• rts/RtsSignals.h
• rts/RtsStartup.c
• rts/RtsSymbols.c
• rts/Schedule.c
• rts/Schedule.h
• rts/StgMiscClosures.cmm
• rts/Threads.c
• rts/Threads.h
• rts/Timer.c
• rts/include/rts/storage/Closures.h
• rts/include/stg/MiscClosures.h
• rts/linker/elf_reloc_riscv64.c
• rts/posix/Poll.c
• rts/posix/Poll.h
• rts/posix/Select.c
• rts/posix/Signals.c
• − rts/posix/Signals.h
• rts/win32/AwaitEvent.c
• rts/win32/ConsoleHandler.c
• rts/win32/ConsoleHandler.h
• testsuite/driver/perf_notes.py
• testsuite/driver/testglobals.py
• testsuite/tests/cmm/should_compile/Makefile
• + testsuite/tests/cmm/should_compile/T27368-ppr-debug.stderr
• − testsuite/tests/cmm/should_compile/T27368-ppr-debug.stdout
• testsuite/tests/cmm/should_compile/all.T
• + testsuite/tests/codeGen/should_run/T27430.hs
• + testsuite/tests/codeGen/should_run/T27430.stdout
• + testsuite/tests/codeGen/should_run/T27430_c.c
• + testsuite/tests/codeGen/should_run/T27533.hs
• + testsuite/tests/codeGen/should_run/T27533.stdout
• + testsuite/tests/codeGen/should_run/T27533_cmm.cmm
• + testsuite/tests/codeGen/should_run/T27537.hs
• + testsuite/tests/codeGen/should_run/T27537.stdout
• + testsuite/tests/codeGen/should_run/T27538.hs
• + testsuite/tests/codeGen/should_run/T27538.stdout
• testsuite/tests/codeGen/should_run/all.T
• + testsuite/tests/concurrent/should_run/T27657a.hs
• + testsuite/tests/concurrent/should_run/T27657a.stdout
• + testsuite/tests/concurrent/should_run/T27657b.hs
• + testsuite/tests/concurrent/should_run/T27657b.stdout
• testsuite/tests/concurrent/should_run/all.T
• 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-mhu007/Makefile
• + testsuite/tests/ghci/prog-mhu007/a/A.hs
• + testsuite/tests/ghci/prog-mhu007/all.T
• + testsuite/tests/ghci/prog-mhu007/b/B.hs
• + testsuite/tests/ghci/prog-mhu007/prog-mhu007.script
• + testsuite/tests/ghci/prog-mhu007/prog-mhu007.stdout
• + testsuite/tests/ghci/prog-mhu007/testpkg-bar/Bar.hs
• + testsuite/tests/ghci/prog-mhu007/testpkg-bar/testpkg-bar.pkg
• + testsuite/tests/ghci/prog-mhu007/testpkg-foo/Foo.hs
• + testsuite/tests/ghci/prog-mhu007/testpkg-foo/testpkg-foo.pkg
• + testsuite/tests/ghci/prog-mhu007/unitA
• + testsuite/tests/ghci/prog-mhu007/unitB
• 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/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/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/all.T
• testsuite/tests/printer/AnnotationNoListTuplePuns.stdout
• + testsuite/tests/printer/Haddock1.hs
• testsuite/tests/printer/Makefile
• testsuite/tests/printer/T18791.stderr
• testsuite/tests/printer/Test20297.stdout
• testsuite/tests/printer/Test24533.stdout
• testsuite/tests/printer/all.T
• testsuite/tests/profiling/should_run/Makefile
• + testsuite/tests/rts/T26408.hs
• + testsuite/tests/rts/T26408.stderr
• testsuite/tests/rts/all.T
• + testsuite/tests/simd/should_run/T27565.hs
• + testsuite/tests/simd/should_run/T27565.stdout
• testsuite/tests/simd/should_run/all.T
• + testsuite/tests/simplCore/should_run/T27705.hs
• + testsuite/tests/simplCore/should_run/T27705.stdout
• + testsuite/tests/simplCore/should_run/T27705_Inst.hs
• testsuite/tests/simplCore/should_run/all.T
• utils/check-exact/ExactPrint.hs
• utils/check-exact/Main.hs
• utils/check-exact/Parsers.hs
• utils/check-exact/Transform.hs
• utils/check-exact/Utils.hs
• utils/ghc-toolchain/src/GHC/Toolchain/Target.hs
• utils/haddock/haddock-api/src/Haddock/Types.hs

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