-
4bfbf5c8
by ARATA Mizuki at 2026-09-01T18:55:08-04:00
testsuite: Fix out-of-bounds access in T3586
unsafeRead and unsafeWrite use 0-based index.
Looking at #3586, the expected output seems to be 2.8e8.
Addresses #27596
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3f9db6d4
by ARATA Mizuki at 2026-09-01T18:55:08-04:00
testsuite: Fix out-of-bounds access in T21305
writeInt64Array# takes an index measured in units of Int64 elements.
Fixes #27596
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44d7788f
by Simon Peyton Jones at 2026-09-01T18:55:53-04:00
Fix buglet in INLINE-arity calculation for pattern synonyms
This fixes #27744.
The buglet was accidentally introduced by
commit 3a0f9a51c1dacc474c7fd128082edd8bf4081256
Author: Simon Peyton Jones <simon.peytonjones@gmail.com>
Date: Sat Aug 1 00:13:02 2026 +0100
Fix three bugs related to required type args and INLINE pragmas
I failed to find all the calls to `addInlinePragArity`!
-
df058f1d
by Simon Jakobi at 2026-09-02T07:18:06-04:00
testsuite: Migrate perf tests off collect_compiler_stats('all')
The 'all' metric argument applies a single tolerance to bytes
allocated, max_bytes_used and peak_megabytes_allocated, although their
noise profiles are incompatible (#27653): allocations are nearly
deterministic, residency needs 10-20%, and peak is quantized to 1 MB.
Any single tolerance is too tight for one metric or too slack for
another. This migrates the remaining users of 'all' (and of the 'all'
default) to explicit per-metric collection, ahead of removing 'all'
from the driver.
peak_megabytes_allocated is dropped everywhere: its 1 MB granularity
makes tight relative windows meaningless (#27613), and it is sensitive
to GC timing. In #27489 it drifted by -5.3% while max_bytes_used moved
by less than 0.1%. Where a test guards a memory property,
max_bytes_used covers it at byte granularity.
Where the motivating ticket was about compile-time memory
(T11545, T15304, T26425), residency remains gated via max_bytes_used,
now with a residency-appropriate tolerance.
max_bytes_used is dropped where residency was only ever an accident of
'all':
* T15630, T15630a, T20261: the underlying tickets (#15630, #20261)
contain no memory data at all. One is a simplifier-ticks blowup and
the other is stated entirely in allocation numbers, so the 20%
window never had teeth.
* T21839c: #21839's measurements show residency essentially flat
(+0.16%) while allocations moved +7%, so allocations are the
discriminating metric. They are already gated at 1% via
collect_compiler_runtime. The ghc/max gate had previously broken CI
spuriously (9fd11585eb widened it from 1% to 10% for that reason).
Allocation tolerances are tightened to the testsuite's conventional 2%
where 'all' previously left them at 10-20%.
Assisted-by: Claude Fable 5
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72dd2432
by Simon Jakobi at 2026-09-02T07:18:06-04:00
testsuite: Remove the 'all' metric argument of collect_stats
'all' gated bytes allocated, max_bytes_used and peak_megabytes_allocated
at a single tolerance, although their noise profiles are incompatible,
making such tests either flaky or toothless (#27653).
Closes #27653.
Assisted-by: Claude Fable 5
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2228cb30
by Simon Jakobi at 2026-09-02T07:18:06-04:00
testsuite: Make the deviation argument of collect_stats mandatory
Almost every caller passes an explicit tolerance matched to the
metric's noise profile, and the silent 20% default is far slacker than
'bytes allocated' merits. Only two tests relied on it. They now state
their tolerance explicitly:
large-project gets 10%, in line with other large compile-time tests.
T9848 gets 2%: its metric is byte-for-byte deterministic across CI
jobs and platforms of a given test_env, has drifted only about 2.5%
since 2015, and the fusion failure it guards against would show up as
a roughly +30000% jump.
Assisted-by: Claude Fable 5
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56291fc5
by Cheng Shao at 2026-09-02T07:18:45-04:00
autoconf/ghc-toolchain: bump llvm upper bound to support llvm 23
This commit bumps llvm upper bound to support llvm 23.
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20eb3f41
by Cheng Shao at 2026-09-02T07:18:45-04:00
rts: fix compilation issues with clang 23
clang 23 has broadened `-Wall`/`-Wextra` ranges, exposing some minor
issues in the rts when building with validate flavours:
- Unused locals
- `#pragma GCC diagnostic pop` mismatch
This commit fixes those.
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9e7739ab
by Simon Jakobi at 2026-09-03T13:45:43-04:00
Add -Wimplicit-field-strictness (#16836)
This opt-in warning fires when a data constructor field lacks an
explicit strictness annotation (`!` or `~`). It complements the
LazyFieldAnnotations extension (4762a8bf30f) from GHC proposal 752,
which makes `~` annotations available for this purpose.
Deciding which fields to report requires their levity, so the check
runs after typechecking. To keep the noise down, the diagnostic is
emitted once per data declaration, grouped by constructor.
Closes #16836.
Assisted-by: Claude Fable 5
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6a44d591
by mangoiv at 2026-09-03T13:46:22-04:00
simplifier: remove a bogus `assert` in `rebuild_app'` in `GHC.CoreToStg.Prep.cpeApp`.
Prior to this commit
commit 08bc245be70d95801bc1138804ed1de9474fbdc0
Author: sheaf <sam.derbyshire@gmail.com>
Date: Sat Feb 28 16:30:43 2026 +0100
Clean up join points, casts & ticks
This commit shores up the logic dealing with casts and ticks occurring
in between a join point binding and a jump
any `PlaceRuntime` ticks we observed were profiling ticks, even though that
isn't necessary.
The more liberal rules in the above commit allow e.g. breakpoint ticks
(which are valid PlaceRuntime ticks) to legitimately appear in an argument
position.
Fixes #27556
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eaa95a6f
by Andrei Borzenkov at 2026-09-04T08:08:40-04:00
Parentheses in prefix GADT constructors (#27423)
Updated `splitLHsGadtTy` to allow looking
through the parentheses for inner binders. General example
of a code pattern that's allowed now:
data S a where
MkS :: (forall a. S a)
That should work now with any combination of nested
foralls and parentheses.
We don't perform parenthesis unwrapping for record
GADT constructors in accordance with GHC Proposal #402.
To this end `con_inner_bndrs` no longer stores plain forall
telescopes: `[HsForAllTelescope pass]` is replaced with
`[LHsGadtTelescope pass]`, a new `HsArg`-style type whose
`HsGadtForAll` holds an inner telescope and whose `HsGadtPar`
holds a pair of parentheses. The parentheses carry no meaning
for renaming or type checking; the only reason to record them
is exact-printing.
Updated `pprConDecl` to improve the `parse == parse . ppr . parse`
property of GADT pretty-printing.
The pretty printer can now output code that's similar to this:
data T a where
MkT1 :: (forall a. T a)
MkT2 :: forall . forall a. T a
These are special cases of inner forall binders
for prefix GADT constructors, when we have either
implicit or zero explicit outer binders.
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639456a8
by Evgeny Malyshev at 2026-09-04T08:09:25-04:00
HsPat: Add spacing to unary tuple patterns
Use hsep when printing unary boxed TuplePat applications so that the
MkSolo constructor is separated from its argument. The old hcat rendered
wildcard and parenthesized arguments as MkSolo_ and MkSolo().
Add T27034 to exercise the HsPat splice-dump path with wildcard and
variable arguments, and update existing affected golden output.
Fixes #27034
Assisted-By: OpenAI Codex
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2908ab36
by Simon Jakobi at 2026-09-05T07:22:17-04:00
X86 NCG: use btr/bts/btc for single-bit operations
Previously the Cmm patterns
x & ~(1 << i)
x | (1 << i)
x ^ (1 << i)
compiled to mov/shl/not/and-style sequences of 3-4 instructions. Now
they compile to a single btr, bts or btc, matching what C compilers
produce.
When the bit index is a literal, constant folding has already collapsed
these patterns into ones with a literal mask, such as
x & 0xfffffeffffffffff for x & ~(1 << 40). Such masks are now also
compiled to a bit-test instruction when they don't fit in an imm32 and
would otherwise have to be loaded into a register first.
For a variable bit index, this applies only when the shift is unchecked
(uncheckedShiftL#, Data.Bits.unsafeShiftL): the bounds-checked shiftL
used by e.g. the default clearBit/setBit/complementBit implementations
wraps the shift in a bounds mask that this optimisation does not see
through. With a literal index, the bounds mask is constant-folded away,
so the checked operations benefit too.
See Note [Bit-test instructions] in GHC.CmmToAsm.X86.CodeGen.
Fixes #25233.
Assisted-by: Claude Fable 5
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c673ecf0
by Simon Peyton Jones at 2026-09-05T07:22:59-04:00
Move HsStatic free-var test to typechecker
A `static` form should have no free *term* variables, but it
can have free *type* variables. Alas, the renamer does not really know what
is a term variable and what is a type variable, because of required type
arguments. This patch moves the test to the typechecker, which does know.
Addresses #27664
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5939ceaf
by sheaf at 2026-09-05T22:06:18-04:00
Windows: enforce path convention in ./configure
As detailed in Note [MSYS paths] in Hadrian.Utilities, the standing
convention (using Windows-style paths with forward slashes) is now
enforced in ./configure instead of within Hadrian, removing the need for
'cygpath' calls within Hadrian.
Fixes #26683
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a6061455
by sheaf at 2026-09-05T22:06:18-04:00
Hadrian: introduce ExeSpawnPath
Specific details about the filepath used to specify the executable to
spawn with CreateProcess matters on Windows: whether we use forward or
backward slashes, a leading ./, or an absolute path changes how the
executable is found.
This commit introduces 'ExeSpawnPath' which is a path that is guaranteed
to be found when spawning a process. All command invocations now go
through this type to ensure the path has been properly sanitised.
See Note [NeedCurrentDirectoryForExePath] in Hadrian.Utilities.
The same treatment is applied to hsc2hs. Updates hsc2hs submodule.
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e28313e3
by sheaf at 2026-09-05T22:07:06-04:00
Preserve tick ordering in 'tickTickedExpr'
'GHC.Core.Utils.tickTickedExpr' tries to combine a tick 't1' into an
existing stack of ticks 't2s'. There are two situations:
1. 't1' is subsumed by a tick in 't2s': drop it.
2. A tick in 't2s' is subsumed by 't1', say 't2'.
This commit ensures that in case (2) we keep 't1' on the outside instead
of replacing 't2' at its position in the stack. This avoids re-ordering
source notes (which was the cause of #27749).
This fixes a regression introduced in 2dadf3b0d05.
Fixes #27749
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3172f557
by sheaf at 2026-09-05T22:07:06-04:00
Consistently prefer local source note ticks
GHC.Cmm.DebugBlock.cmmDebugGen (DWARF annotations) and
GHC.Stg.Debug.quickSourcePos (-finfo-table-map) both contained logic to
prioritise source note ticks from the current module.
This commit commons up this logic and propagates it to a third consumer:
IPE stack frames, in GHC.Driver.GenerateCgIPEStub.
See the new function GHC.Types.Tickish.bestSourceNote.
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192be0b6
by Luite Stegeman at 2026-09-07T19:43:36-04:00
rts: fix ctoi_tuple_spill_words getting out of sync
Fix a few places that were not updating ctoi_tuple_spill_words
correctly, leading to corruption/crashes when dealing with large
unboxed tuples in bytecode:
- captureContinuationAndAbort
- findRetryFrameHelper/findAtomicallyFrameHelper
- interpretBCO bci_BRK_FUN
fixes #27633
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604eb43c
by Simon Jakobi at 2026-09-07T19:44:15-04:00
Hadrian: don't capture the testsuite driver's output (#27780)
a6061455d54 switched the Testsuite RunTest case from Shake's cmd to the
cmd' wrapper. cmd' always captures stdout and stderr, and since the
caller asks for Exit, it returns without dumping what it captured. As a
result the testsuite output no longer appears in CI job logs: failures,
performance metrics and the summary were lost with the job.
Use cmdExe, the uncaptured cmd, as the other plain-cmd sites in that
commit do.
Fixes #27780.
Assisted-by: Claude Fable 5.1
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06eee015
by Luite Stegeman at 2026-09-08T06:03:06+02:00
rts: Fix missing memory barrier in eval_thunk_selector (#27477)
unchain_thunk_selectors() was missing an ACQUIRE_LOAD for the
indirectee, leading to segfaults and corruption during GC on
weakly-ordered architectures.
Fixes #27477
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f8b2bd8f
by Alan Zimmerman at 2026-09-08T09:39:12-04:00
EPA Fix HsCmdDo exact print with comments
Exact printing of HsCmdDo was ignoring the location for the do
statements, and this is an annotation that can have comments in it.
Update it so we print the statements as a unit, including any
comments.
Also add the result of auditing that we capture comments in all needed
places, noting that the remaining Anno SrcSpan instances are benign.
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54f51068
by Rodrigo Mesquita at 2026-09-08T14:46:32+01:00
wip: global break action for multi thread support
the status Var must actually be global across all threads, otherwise all of them will block trying to write some Status Var no one is looking at at all
have to fix these toggle untoggle things
very satisfying solution with mutable state
Matthew-certified big brain
WIP
HMmm almost there I think
pretty great progressssssssss
ExecOptions isolateThreadBreaks
ThreadBreaksIsolationMode
move to GHCi.Run.Breakpoints