-
f85058d3
by Zubin Duggal at 2025-10-17T13:50:52+05:30
compiler: Attempt to systematize Unique tags by introducing an ADT for each different tag
Fixes #26264
Metric Decrease:
T9233
-
c85c845d
by sheaf at 2025-10-17T22:35:32-04:00
Don't prematurely final-zonk PatSyn declarations
This commit makes GHC hold off on the final zonk for pattern synonym
declarations, in 'GHC.Tc.TyCl.PatSyn.tc_patsyn_finish'.
This accommodates the fact that pattern synonym declarations without a
type signature can contain unfilled metavariables, e.g. if the RHS of
the pattern synonym involves view-patterns whose type mentions promoted
(level 0) metavariables. Just like we do for ordinary function bindings,
we should allow these metavariables to be settled later, instead of
eagerly performing a final zonk-to-type.
Now, the final zonking-to-type for pattern synonyms is performed in
GHC.Tc.Module.zonkTcGblEnv.
Fixes #26465
-
ba3e5bdd
by Rodrigo Mesquita at 2025-10-18T16:57:18-04:00
Move code-gen aux symbols from ghc-internal to rts
These symbols were all previously defined in ghc-internal and made the
dependency structure awkward, where the rts may refer to some of these
symbols and had to work around that circular dependency the way
described in #26166.
Moreover, the code generator will produce code that uses these symbols!
Therefore, they should be available in the rts:
PRINCIPLE: If the code generator may produce code which uses this
symbol, then it should be defined in the rts rather than, say,
ghc-internal.
That said, the main motivation is towards fixing #26166.
Towards #26166. Pre-requisite of !14892
-
f31de2a9
by Ben Gamari at 2025-10-18T16:57:18-04:00
rts: Avoid static symbol references to ghc-internal
This resolves #26166, a bug due to new constraints placed by Apple's
linker on undefined references.
One source of such references in the RTS is the many symbols referenced
in ghc-internal. To mitigate #26166, we make these references dynamic,
as described in Note [RTS/ghc-internal interface].
Fixes #26166
Co-authored-by: Rodrigo Mesquita <rodrigo.m.mesquita@gmail.com>
Co-authored-by: Cheng Shao <terrorjack@type.dance>
-
43fdfddc
by Ben Gamari at 2025-10-18T16:57:18-04:00
compiler: Rename isMathFun -> isLibcFun
This set includes more than just math functions.
-
4ed5138f
by Ben Gamari at 2025-10-18T16:57:18-04:00
compiler: Add libc allocator functions to libc_funs
Prototypes for these are now visible from `Prim.h`, resulting in
multiple-declaration warnings in the unregisterised job.
-
9a0a076b
by Ben Gamari at 2025-10-18T16:57:18-04:00
rts: Minimize header dependencies of Prim.h
Otherwise we will end up with redundant and incompatible declarations
resulting in warnings during the unregisterised build.
-
26b8a414
by Diego Antonio Rosario Palomino at 2025-10-18T16:58:10-04:00
Cmm Parser: Fix incorrect example in comment
The Parser.y file contains a comment with an incorrect example of textual
Cmm (used in .cmm files). This commit updates the comment to ensure it
reflects valid textual Cmm syntax.
Fixes #26313
-
d4a9d6d6
by ARATA Mizuki at 2025-10-19T18:43:47+09:00
Handle implications between x86 feature flags
This includes:
* Multiple -msse* options can be specified
* -mavx implies -msse4.2
* -mavx2 implies -mavx
* -mfma implies -mavx
* -mavx512f implies -mavx2 and -mfma
* -mavx512{cd,er,pf} imply -mavx512f
Closes #24989
Co-authored-by: sheaf <sam.derbyshire@gmail.com>
-
c9b8465c
by Cheng Shao at 2025-10-20T10:16:00-04:00
wasm: workaround WebKit bug in dyld
This patch works around a WebKit bug and allows dyld to run on WebKit
based platforms as well. See added note for detailed explanation.
Co-authored-by: Codex <codex@openai.com>
-
91b6be10
by Julian Ospald at 2025-10-20T18:21:03-04:00
Improve error handling in 'getPackageArchives'
When the library dirs in the package conf files are not set up correctly,
the JS linker will happily ignore such packages and not link against them,
although they're part of the link plan.
Fixes #26383
-
6c5269da
by Sven Tennie at 2025-10-20T18:21:44-04:00
Align coding style
Improve readability by using the same style for all constructor calls in
this function.
-
3d305889
by Sven Tennie at 2025-10-20T18:21:44-04:00
Reduce complexity by removing joins with mempty
ldArgs, cArgs and cppArgs are all `mempty`. Thus concatenating them adds
nothing but some complexity while reading the code.
-
38d65187
by Matthew Pickering at 2025-10-21T13:12:20+01:00
Fix stack decoding when using profiled runtime
There are three fixes in this commit.
* We need to replicate the `InfoTable` and `InfoTableProf`
approach for the other stack constants (see the new Stack.ConstantsProf
file).
* Then we need to appropiately import the profiled or non-profiled
versions.
* Finally, there was an incorrect addition in `stackFrameSize`. We need
to cast after performing addition on words.
Fixes #26507
-
17231bfb
by fendor at 2025-10-21T13:12:20+01:00
Add regression test for #26507
-
4f5bf93b
by Simon Peyton Jones at 2025-10-25T04:05:34-04:00
Postscript to fix for #26255
This MR has comments only
-
6ef22fa0
by IC Rainbow at 2025-10-26T18:23:01-04:00
Add SIMD primops for bitwise logical operations
This adds 128-bit wide and/or/xor instructions for X86 NCG,
with both SSE and AVX encodings.
```
andFloatX4# :: FloatX4# -> FloatX4# -> FloatX4# -- andps / vandps
andDoubleX2# :: DoubleX2# -> DoubleX2# -> DoubleX2# -- andpd / vandpd
andInt8X16# :: Int8X16# -> Int8X16# -> Int8X16# -- pand / vpand
```
The new primops are available on ARM when using LLVM backend.
Tests added:
- simd015 (floats and doubles)
- simd016 (integers)
- simd017 (words)
Fixes #26417
-
fbdc623a
by sheaf at 2025-10-26T18:23:52-04:00
Add hints for unsolved HasField constraints
This commit adds hints and explanations for unsolved 'HasField'
constraints.
GHC will now provide additional explanations for an unsolved constraint
of the form 'HasField fld_name rec_ty fld_ty'; the details are laid out in
Note [Error messages for unsolved HasField constraints], but briefly:
1. Provide similar name suggestions (e.g. mis-spelled field name)
and import suggestions (record field not in scope).
These result in actionable 'GhcHints', which is helpful to provide
code actions in HLS.
2. Explain why GHC did not solve the constraint, e.g.:
- 'fld_name' is not a string literal (e.g. a type variable)
- 'rec_ty' is a TyCon without any fields, e.g. 'Int' or 'Bool'.
- 'fld_ty' contains existentials variables or foralls.
- The record field is a pattern synonym field (GHC does not generate
HasField instances for those).
- 'HasField' is a custom 'TyCon', not actually the built-in
'HasField' typeclass from 'GHC.Records'.
On the way, we slightly refactor the mechanisms for import suggestions
in GHC.Rename.Unbound. This is to account for the fact that, for
'HasField', we don't care whether the field is imported qualified or
unqualified. 'importSuggestions' was refactored, we now have
'sameQualImportSuggestions' and 'anyQualImportSuggestions'.
Fixes #18776 #22382 #26480
-
99d5707f
by sheaf at 2025-10-26T18:23:52-04:00
Rename PatSyn MatchContext to PatSynCtx to avoid punning
-
5dc2e9ea
by Julian Ospald at 2025-10-27T18:17:23-04:00
Skip uniques test if sources are not available
-
544b9ec9
by Vladislav Zavialov at 2025-10-27T18:18:06-04:00
Re-export GHC.Hs.Basic from GHC.Hs
Clean up some import sections in GHC by re-exporting GHC.Hs.Basic
from GHC.Hs.
-
643ce801
by Julian Ospald at 2025-10-28T18:18:55-04:00
rts: remove unneccesary cabal flags
We perform those checks via proper autoconf macros
instead that do the right thing and then add those
libs to the rts buildinfo.
-
d69ea8fe
by Vladislav Zavialov at 2025-10-28T18:19:37-04:00
Test case for #17705
Starting with GHC 9.12 (the first release to include 5745dbd3),
all examples in this ticket are handled as expected.
-
4038a28b
by Andreas Klebinger at 2025-10-30T12:38:52-04:00
Add a perf test for #26425
-
f997618e
by Andreas Klebinger at 2025-10-30T12:38:52-04:00
OccAnal: Be stricter for better compiler perf.
In particular we are now stricter:
* When combining usageDetails.
* When computing binder info.
In combineUsageDetails when combining the underlying adds we compute a
new `LocalOcc` for each entry by combining the two existing ones.
Rather than wait for those entries to be forced down the road we now
force them immediately. Speeding up T26425 by about 10% with little
effect on the common case.
We also force binders we put into the Core AST everywhere now.
Failure to do so risks leaking the occ env used to set the binders
OccInfo.
For T26425 compiler residency went down by a factor of ~10x.
Compile time also improved by a factor of ~1.6.
-------------------------
Metric Decrease:
T18698a
T26425
T9233
-------------------------
-
5618645b
by Vladislav Zavialov at 2025-10-30T12:39:33-04:00
Fix namespace specifiers in subordinate exports (#12488)
This patch fixes an oversight in the `lookupChildrenExport` function that
caused explicit namespace specifiers of subordinate export items to be
ignored:
module M (T (type A)) where -- should be rejected
data T = A
Based on the `IEWrappedName` data type, there are 5 cases to consider:
1. Unadorned name: P(X)
2. Named default: P(default X)
3. Pattern synonym: P(pattern X)
4. Type name: P(type X)
5. Data name: P(data X)
Case 1 is already handled correctly; cases 2 and 3 are parse errors; and
it is cases 4 and 5 that we are concerned with in this patch.
Following the precedent established in `LookupExactName`, we introduce
a boolean flag in `LookupChildren` to control whether to look up in all
namespaces or in a specific one. If an export item is accompanied by an
explicit namespace specifier `type` or `data`, we restrict the lookup in
`lookupGRE` to a specific namespace.
The newly introduced diagnostic `TcRnExportedSubordinateNotFound`
provides error messages and suggestions more tailored to this context
than the previously used `reportUnboundName`.
-
f75ab223
by Peter Trommler at 2025-10-31T18:43:13-04:00
ghc-toolchain: detect PowerPC 64 bit ABI
Check preprocessor macro defined for ABI v2 and assume v1 otherwise.
Fixes #26521
-
d086c474
by Peter Trommler at 2025-10-31T18:43:13-04:00
ghc-toolchain: refactor, move lastLine to Utils
-
995dfe0d
by Vladislav Zavialov at 2025-10-31T18:43:54-04:00
Tests for -Wduplicate-exports, -Wdodgy-exports
Add test cases for the previously untested diagnostics:
[GHC-51876] TcRnDupeModuleExport
[GHC-64649] TcRnNullExportedModule
This also revealed a typo (incorrect capitalization of "module") in the
warning text for TcRnDupeModuleExport, which is now fixed.
-
f6961b02
by Cheng Shao at 2025-11-01T00:08:01+01:00
wasm: reformat dyld source code
This commit reformats dyld source code with prettier, to avoid
introducing unnecessary diffs in subsequent patches when they're
formatted before committing.
-
0c9032a0
by Cheng Shao at 2025-11-01T00:08:01+01:00
wasm: simplify _initialize logic in dyld
This commit simplifies how we _initialize a wasm shared library in
dyld and removes special treatment for libc.so, see added comment for
detailed explanation.
-
ec1b40bd
by Cheng Shao at 2025-11-01T00:08:01+01:00
wasm: support running dyld fully client side in the browser
This commit refactors the wasm dyld script so that it can be used to
load and run wasm shared libraries fully client-side in the browser
without needing a wasm32-wasi-ghci backend:
- A new `DyLDBrowserHost` class is exported, which runs in the browser
and uses the in-memory vfs without any RPC calls. This meant to be
used to create a `rpc` object for the fully client side use cases.
- The exported `main` function now can be used to load user-specified
shared libraries, and the user can use the returned `DyLD` instance
to run their own exported Haskell functions.
- The in-browser wasi implementation is switched to
https://github.com/haskell-wasm/browser_wasi_shim for bugfixes and
major performance improvements not landed upstream yet.
- When being run by deno, it now correctly switches to non-nodejs code
paths, so it's more convenient to test dyld logic with deno.
See added comments for details, as well as the added `playground001`
test case for an example of using it to build an in-browser Haskell
playground.
-
8f3e481f
by Cheng Shao at 2025-11-01T00:08:01+01:00
testsuite: add playground001 to test haskell playground
This commit adds the playground001 test case to test the haskell
playground in browser, see comments for details.
-
af40606a
by Cheng Shao at 2025-11-01T00:08:04+01:00
Revert "testsuite: add T26431 test case"
This reverts commit 695036686f8c6d78611edf3ed627608d94def6b7. T26431
is now retired, wasm ghc internal-interpreter logic is tested by
playground001.
-
86c82745
by Vladislav Zavialov at 2025-11-01T07:24:29-04:00
Supplant TcRnExportHiddenComponents with TcRnDodgyExports (#26534)
Remove a bogus special case in lookup_ie_kids_all,
making TcRnExportHiddenComponents obsolete.
-
fcf6331e
by Richard Eisenberg at 2025-11-03T08:33:05+00:00
Refactor fundep solving
This commit is a large-scale refactor of the increasingly-messy code that
handles functional dependencies. It has virtually no effect on what compiles
but improves error messages a bit. And it does the groundwork for #23162.
The big picture is described in
Note [Overview of functional dependencies in type inference]
in GHC.Tc.Solver.FunDeps
* New module GHC.Tc.Solver.FunDeps contains all the fundep-handling
code for the constraint solver.
* Fundep-equalities are solved in a nested scope; they may generate
unifications but otherwise have no other effect.
See GHC.Tc.Solver.FunDeps.solveFunDeps
The nested needs to start from the Givens in the inert set, but
not the Wanteds; hence a new function `resetInertCans`, used in
`nestFunDepsTcS`.
* That in turn means that fundep equalities never show up in error
messages, so the complicated FunDepOrigin tracking can all disappear.
* We need to be careful about tracking unifications, so we kick out
constraints from the inert set after doing unifications. Unification
tracking has been majorly reformed: see Note [WhatUnifications] in
GHC.Tc.Utils.Unify.
A good consequence is that the hard-to-grok `resetUnificationFlag`
has been replaced with a simpler use of
`reportCoarseGrainUnifications`
Smaller things:
* Rename `FunDepEqn` to `FunDepEqns` since it contains multiple
type equalities.
Some compile time improvement
Metrics: compile_time/bytes allocated
Baseline
Test value New value Change
---------------------- --------------------------------------
T5030(normal) 173,839,232 148,115,248 -14.8% GOOD
hard_hole_fits(normal) 286,768,048 284,015,416 -1.0%
geo. mean -0.2%
minimum -14.8%
maximum +0.3%
Metric Decrease:
T5030
-
231adc30
by Simon Peyton Jones at 2025-11-03T08:33:05+00:00
QuickLook's tcInstFun should make instantiation variables directly
tcInstFun must make "instantiation variables", not regular
unification variables, when instantiating function types. That was
previously implemented by a hack: set the /ambient/ level to QLInstTyVar.
But the hack finally bit me, when I was refactoring WhatUnifications.
And it was always wrong: see the now-expunged (TCAPP2) note.
This commit does it right, by making tcInstFun call its own
instantiation functions. That entails a small bit of duplication,
but the result is much, much cleaner.
-
39d4a24b
by Simon Peyton Jones at 2025-11-03T08:33:05+00:00
Build implication for constraints from (static e)
This commit addresses #26466, by buiding an implication for the
constraints arising from a (static e) form. The implication has
a special ic_info field of StaticFormSkol, which tells the constraint
solver to use an empty set of Givens.
See (SF3) in Note [Grand plan for static forms]
in GHC.Iface.Tidy.StaticPtrTable
This commit also reinstates an `assert` in GHC.Tc.Solver.Equality.
The test `StaticPtrTypeFamily` was failing with an assertion failure,
but it now works.
-
2e2aec1e
by Simon Peyton Jones at 2025-11-03T08:33:05+00:00
Comments about defaulting representation equalities
-
52a4d1da
by Simon Peyton Jones at 2025-11-03T08:33:05+00:00
Improve tracking of rewriter-sets
This refactor substantially improves the treatment of so-called
"rewriter-sets" in the constraint solver.
The story is described in the rewritten
Note [Wanteds rewrite Wanteds: rewriter-sets]
in GHC.Tc.Types.Constraint
Some highlights
* Trace the free coercion holes of a filled CoercionHole,
in CoercionPlusHoles. See Note [Coercion holes] (COH5)
This avoids taking having to take the free coercion variables
of a coercion when zonking a rewrriter-set
* Many knock on changes
* Make fillCoercionHole take CoercionPlusHoles as its argument
rather than to separate arguments.
* Similarly setEqIfWanted, setWantedE, wrapUnifierAndEmit.
* Be more careful about passing the correct CoHoleSet to
`rewriteEqEvidence` and friends
* Make kickOurAfterFillingCoercionHole more clever. See
new Note [Kick out after filling a coercion hole]
Smaller matters
* Rename RewriterSet to CoHoleSet
* Add special-case helper `rewriteEqEvidenceSwapOnly`
-
3e78e1ba
by Simon Peyton Jones at 2025-11-03T08:33:05+00:00
Tidy up constraint solving for foralls
* In `can_eq_nc_forall` make sure to track Givens that are used
in the nested solve step.
* Tiny missing-swap bug-fix in `lookup_eq_in_qcis`
* Fix some leftover mess from
commit 14123ee646f2b9738a917b7cec30f9d3941c13de
Author: Simon Peyton Jones <simon.peytonjones@gmail.com>
Date: Wed Aug 20 00:35:48 2025 +0100
Solve forall-constraints via an implication, again
Specifically, trySolveImplication is now dead.
-
973f2c25
by Simon Peyton Jones at 2025-11-03T08:33:05+00:00
Do not treat CoercionHoles as free variables in coercions
This fixes a long-standing wart in the free-variable finder;
now CoercionHoles are no longer treated as a "free variable"
of a coercion.
I got big and unexpected performance regressions when making
this change. Turned out that CallArity didn't discover that
the free variable finder could be eta-expanded, which gave very
poor code.
So I re-used Note [The one-shot state monad trick] for Endo,
resulting in GHC.Utils.EndoOS. Very simple, big win.
-
c2b8a0f9
by Simon Peyton Jones at 2025-11-03T08:33:05+00:00
Update debug-tracing in CallArity
No effect on behaviour, and commented out anyway
-
9aa5ee99
by Simon Peyton Jones at 2025-11-03T08:33:28+00:00
Comments only -- remove dangling Note references
-
6683f183
by Simon Peyton Jones at 2025-11-03T08:33:28+00:00
Accept error message wibbles
-
3ba3d9f9
by Luite Stegeman at 2025-11-04T00:59:41-05:00
rts: fix eager black holes: record mutated closure and fix assertion
This fixes two problems with handling eager black holes, introduced
by a1de535f762bc23d4cf23a5b1853591dda12cdc9.
- the closure mutation must be recorded even for eager black holes,
since the mutator has mutated it before calling threadPaused
- The assertion that an unmarked eager black hole must be owned by
the TSO calling threadPaused is incorrect, since multiple threads
can race to claim the black hole.
fixes #26495
-
b5508f2c
by Rodrigo Mesquita at 2025-11-04T14:10:56+00:00
build: Relax ghc/ghc-boot Cabal bound to 3.16
Fixes #26202
-
c5b3541f
by Rodrigo Mesquita at 2025-11-04T14:10:56+00:00
cabal-reinstall: Use haddock-api +in-tree-ghc
Fixes #26202
-
c6d4b945
by Rodrigo Mesquita at 2025-11-04T14:10:56+00:00
cabal-reinstall: Pass --strict to Happy
This is necessary to make the generated Parser build successfully
This mimics Hadrian, which always passes --strict to happy.
Fixes #26202
-
79df1e0e
by Rodrigo Mesquita at 2025-11-04T14:10:56+00:00
genprimopcode: Require higher happy version
I've bumped the happy version to forbid deprecated Happy versions which
don't successfully compile.
-
fa5d33de
by Simon Peyton Jones at 2025-11-05T08:35:40-05:00
Add a HsWrapper optimiser
This MR addresses #26349, by introduceing optSubTypeHsWrapper.
There is a long
Note [Deep subsumption and WpSubType]
in GHC.Tc.Types.Evidence that explains what is going on.
-
ea58cae5
by Simon Peyton Jones at 2025-11-05T08:35:40-05:00
Improve mkWpFun_FRR
This commit ensures that `mkWpFun_FRR` directly produces a `FunCo` in
the cases where it can.
(Previously called `mkWpFun` which in turn optimised to a `FunCo`, but
that made the smarts in `mkWpFun` /essential/ rather than (as they
should be) optional.
-
5cdcfaed
by Ben Gamari at 2025-11-06T09:01:36-05:00
compiler: Exclude units with no exposed modules from unused package check
Such packages cannot be "used" in the Haskell sense of the word yet
are nevertheless necessary as they may provide, e.g., C object code or
link flags.
Fixes #24120.
-
74b8397a
by Brandon Chinn at 2025-11-06T09:02:19-05:00
Replace deprecated argparse.FileType
-
36ddf988
by Ben Gamari at 2025-11-06T09:03:01-05:00
Bump unix submodule to 2.8.8.0
Closes #26474.
-
c32b3a29
by fendor at 2025-11-06T09:03:43-05:00
Fix assertion in `postStringLen` to account for \0 byte
We fix the assertion to handle trailing \0 bytes in `postStringLen`.
Before this change, the assertion looked like this:
ASSERT(eb->begin + eb->size > eb->pos + len + 1);
Let's assume some values to see why this is actually off by one:
eb->begin = 0
eb->size = 1
eb->pos = 0
len = 1
then the assertion would trigger correctly:
0 + 1 > 0 + 1 + 1 => 1 > 2 => false
as there is not enough space for the \0 byte (which is the trailing +1).
However, if we change `eb->size = 2`, then we do have enough space for a
string of length 1, but the assertion still fails:
0 + 2 > 0 + 1 + 1 => 2 > 2 => false
Which causes the assertion to fail if there is exactly enough space for
the string with a trailing \0 byte.
Clearly, the assertion should be `>=`!
If we switch around the operand, it should become more obvious that `<=`
is the correct comparison:
ASSERT(eb->pos + len + 1 <= eb->begin + eb->size);
This is expresses more naturally that the current position plus the
length of the string (and the null byte) must be smaller or equal to the
overall size of the buffer.
This change also is in line with the implementation in
`hasRoomForEvent` and `hasRoomForVariableEvent`:
```
StgBool hasRoomForEvent(EventsBuf *eb, EventTypeNum eNum)
{
uint32_t size = ...;
if (eb->pos + size > eb->begin + eb->size)
...
```
the check `eb->pos + size > eb->begin + eb->size` is identical to
`eb->pos + size <= eb->begin + eb->size` plus a negation.
-
3034a6f2
by Ben Gamari at 2025-11-06T09:04:24-05:00
Bump os-string submodule to 2.0.8
-
39567e85
by Cheng Shao at 2025-11-06T09:05:06-05:00
rts: use computed goto for instruction dispatch in the bytecode interpreter
This patch uses computed goto for instruction dispatch in the bytecode
interpreter. Previously instruction dispatch is done by a classic
switch loop, so executing the next instruction requires two jumps: one
to the start of the switch loop and another to the case block based on
the instruction tag. By using computed goto, we can build a jump table
consisted of code addresses indexed by the instruction tags
themselves, so executing the next instruction requires only one jump,
to the destination directly fetched from the jump table.
Closes #12953.
-
93fc7265
by sheaf at 2025-11-06T21:33:24-05:00
Correct hasFixedRuntimeRep in matchExpectedFunTys
This commit fixes a bug in the representation-polymormorphism check in
GHC.Tc.Utils.Unify.matchExpectedFunTys. The problem was that we put
the coercion resulting from hasFixedRuntimeRep in the wrong place,
leading to the Core Lint error reported in #26528.
The change is that we have to be careful when using 'mkWpFun': it
expects **both** the expected and actual argument types to have a
syntactically fixed RuntimeRep, as explained in Note [WpFun-FRR-INVARIANT]
in GHC.Tc.Types.Evidence.
On the way, this patch improves some of the commentary relating to
other usages of 'mkWpFun' in the compiler, in particular in the view
pattern case of 'tc_pat'. No functional changes, but some stylistic
changes to make the code more readable, and make it easier to understand
how we are upholding the WpFun-FRR-INVARIANT.
Fixes #26528
-
c052c724
by Simon Peyton Jones at 2025-11-06T21:34:06-05:00
Fix a horrible shadowing bug in implicit parameters
Fixes #26451. The change is in GHC.Tc.Solver.Monad.updInertDicts
where we now do /not/ delete /Wanted/ implicit-parameeter constraints.
This bug has been in GHC since 9.8! But it's quite hard to provoke;
I contructed a tests in T26451, but it was hard to do so.
-
b253013e
by Georgios Karachalias at 2025-11-07T17:21:57-05:00
Remove the `CoreBindings` constructor from `LinkablePart`
Adjust HscRecompStatus to disallow unhydrated WholeCoreBindings
from being passed as input to getLinkDeps (which would previously
panic in this case).
Fixes #26497
-
ac7b737e
by Sylvain Henry at 2025-11-07T17:22:51-05:00
Testsuite: pass ext-interp test way (#26552)
Note that some tests are still marked as broken with the ext-interp way
(see #26552 and #14335)
-
3c2f4bb4
by sheaf at 2025-11-11T11:47:28-05:00
Preserve user-written kinds in data declarations
This commit ensures that we preserve the user-written kind for data
declarations, e.g. in
type T2T = Type -> Type
type D :: T2T
data D a where { .. }
that we preserve the user-written kind of D as 'T2T', instead of
expanding the type synonym 'T2T' during kind checking.
We do this by storing 'tyConKind' separately from 'tyConResKind'. This
means that 'tyConKind' is not necessarily equal to
'mkTyConKind binders res_kind', as e.g. in the above example the former
is 'T2T' while the latter is 'Type -> Type'.
This is explained in Note [Preserve user-written TyCon kind] in GHC.Core.TyCon.
This is particularly important for Haddock, as the kinds stored in
interface files affect the generated documentation, and we want to
preserve the user-written types as much as possible.
-
19859584
by sheaf at 2025-11-11T11:47:28-05:00
Store user-written datacon tvs in interface files
This commit ensures we store the user-written quantified type variables
of data constructors in interface files, e.g. in
data D a where
MkD1 :: forall x. x -> D x
MkD2 :: forall u v. u -> v -> D v
The previous behaviour was to rename the universal variables to match
the universal variables of the data constructor. This was undesirable
because the names that end up in interface files end up mattering for
generated Haddock documentation; it's better to preserve the user-written
type variables.
Moreover, the universal variables may not have been user-written at all,
e.g. in an example such as:
type T2T = Type -> Type
data G :: T2T where
MkG :: forall x. D x
Here GHC will invent the type variable name 'a' for the first binder of
the TyCon G. We really don't want to then rename the user-written 'x'
into the generated 'a'.
-
034b2056
by sheaf at 2025-11-11T11:47:28-05:00
DataCon univ_tvs names: pick TyCon over inferred
This commit changes how we compute the names of universal type variables
in GADT data constructors. This augments the existing logic that chose
which type variable name to use, in GHC.Tc.TyCl.mkGADTVars. We continue
to prefer DataCon tv names for user-written binders, but we now prefer
TyCon tv names for inferred (non-user-written) DataCon binders.
This makes a difference in examples such as:
type (:~~:) :: k1 -> k2 -> Type
data a :~~: b where
HRefl :: a :~~: a
Before this patch, we ended up giving HRefl the type:
forall {k2}. forall (a :: k2). a :~~: a
whereas we now give it the type:
forall {k1}. forall (a :: k1). a :~~: a
The important part isn't really 'k1' or 'k2', but more that the inferred
type variable names of the DataCon can be arbitrary/unpredictable (as
they are chosen by GHC and depend on how unification proceeds), so it's
much better to use the more predictable TyCon type variable names.
-
95078d00
by sheaf at 2025-11-11T11:47:28-05:00
Backpack Rename: use explicit record construction
This commit updates the Backpack boilerplate in GHC.Iface.Rename to
use explicit record construction rather than record update. This makes
sure that the code stays up to date when the underlying constructors
change (e.g. new fields are added). The rationale is further explained
in Note [Prefer explicit record construction].
-
2bf36263
by sheaf at 2025-11-11T11:47:28-05:00
Store # eta binders in TyCon and use for Haddock
This commit stores the number of TyCon binders that were introduced by
eta-expansion (by the function GHC.Tc.Gen.HsType.splitTyConKind).
This is then used to pretty-print the TyCon as the user wrote it, e.g.
for
type Effect :: (Type -> Type) -> Type -> Type
data State s :: Effect where {..} -- arity 3
GHC will eta-expand the data declaration to
data State s a b where {..}
but also store in the 'TyCon' that the number of binders introduced by
this eta expansion is 2. This allows us, in
'Haddock.Convert.synifyTyConKindSig', to recover the original user-written
syntax, preserving the user's intent in Haddock documentation.
See Note [Inline kind signatures with GADTSyntax] in Haddock.Convert.
-
6c91582f
by Matthew Pickering at 2025-11-11T11:48:12-05:00
driver: Properly handle errors during LinkNode steps
Previously we were not properly catching errors during the LinkNode step
(see T9930fail test).
This is fixed by wrapping the `LinkNode` action in `wrapAction`, the
same handler which is used for module compilation.
Fixes #26496
-
e1e1eb32
by Matthew Pickering at 2025-11-11T11:48:54-05:00
driver: Remove unecessary call to hscInsertHPT
This call was left-over from e9445c013fbccf9318739ca3d095a3e0a2e1be8a
If you follow the functions which call `upsweep_mod`, they immediately
add the interface to the HomePackageTable when `upsweep_mod` returns.
-
b22777d4
by ARATA Mizuki at 2025-11-11T11:49:44-05:00
LLVM backend: Pass the +evex512 attribute to LLVM 18+ if -mavx512f is set
The newer LLVM requires the +evex512 attribute to enable use of ZMM registers.
LLVM exhibits a backward-compatible behavior if the cpu is `x86-64`, but not if `penryn`.
Therefore, on macOS, where the cpu is set to `penryn`, we need to explicitly pass +evex512.
Fixes #26410
-
6ead7d06
by Vladislav Zavialov at 2025-11-11T11:50:26-05:00
Comments only in GHC.Parser.PostProcess.Haddock
Remove outdated Note [Register keyword location], as the issue it describes
was addressed by commit 05eb50dff2fcc78d025e77b9418ddb369db49b9f.
-
43fa8be8
by sheaf at 2025-11-11T11:51:18-05:00
localRegistersConflict: account for assignment LHS
This commit fixes a serious oversight in GHC.Cmm.Sink.conflicts,
specifically the code that computes which local registers conflict
between an assignment and a Cmm statement.
If we have:
assignment: <local_reg> = <expr>
node: <local_reg> = <other_expr>
then clearly the two conflict, because we cannot move one statement past
the other, as they assign two different values to the same local
register. (Recall that 'conflicts (local_reg,expr) node' is False if and
only if the assignment 'local_reg = expr' can be safely commuted past
the statement 'node'.)
The fix is to update 'GHC.Cmm.Sink.localRegistersConflict' to take into
account the following two situations:
(1) 'node' defines the LHS local register of the assignment,
(2) 'node' defines a local register used in the RHS of the assignment.
The bug is precisely that we were previously missing condition (1).
Fixes #26550
-
79dfcfe0
by sheaf at 2025-11-11T11:51:18-05:00
Update assigned register format when spilling
When we come to spilling a register to put new data into it, in
GHC.CmmToAsm.Reg.Linear.allocRegsAndSpill_spill, we need to:
1. Spill the data currently in the register. That is, do a spill
with a format that matches what's currently in the register.
2. Update the register assignment, allocating a virtual register to
this real register, but crucially **updating the format** of this
assignment.
Due to shadowing in the Haskell code for allocRegsAndSpill_spill, we
were mistakenly re-using the old format. This could lead to a situation
where:
a. We were using xmm6 to store a Double#.
b. We want to store a DoubleX2# into xmm6, so we spill the current
content of xmm6 to the stack using a scalar move (correct).
c. We update the register assignment, but we fail to update the format
of the assignment, so we continue to think that xmm6 stores a
Double# and not a DoubleX2#.
d. Later on, we need to spill xmm6 because it is getting clobbered by
another instruction. We then decide to only spill the lower 64 bits
of the register, because we still think that xmm6 only stores a
Double# and not a DoubleX2#.
Fixes #26542
-
aada5db9
by ARATA Mizuki at 2025-11-11T11:52:07-05:00
Fix the order of spill/reload instructions
The AArch64 NCG could emit multiple instructions for a single spill/reload,
but their order was not consistent between the definition and a use.
Fixes #26537
Co-authored-by: sheaf <sam.derbyshire@gmail.com>
-
64ec82ff
by Andreas Klebinger at 2025-11-11T11:52:48-05:00
Add hpc to release script
-
741da00c
by Ben Gamari at 2025-11-12T03:38:20-05:00
template-haskell: Better describe getQ semantics
Clarify that the state is a type-indexed map, as suggested by #26484.
-
8b080e04
by ARATA Mizuki at 2025-11-12T03:39:11-05:00
Fix incorrect markups in the User's Guide
* Correct markup for C--: "C-\-" in reST
* Fix internal links
* Fix code highlighting
* Fix inline code: Use ``code`` rather than `code`
* Remove extra backslashes
Fixes #16812
Co-authored-by: sheaf <sam.derbyshire@gmail.com>
-
a00840ea
by Simon Peyton Jones at 2025-11-14T15:23:56+00:00
Make TYPE and CONSTRAINT apart again
This patch finally fixes #24279.
* The story started with #11715
* Then #21623 articulated a plan, which made Type and Constraint
not-apart; a horrible hack but it worked. The main patch was
commit 778c6adca2c995cd8a1b84394d4d5ca26b915dac
Author: Simon Peyton Jones <simonpj@microsoft.com>
Date: Wed Nov 9 10:33:22 2022 +0000
Type vs Constraint: finally nailed
* #24279 reported a bug in the above big commit; this small patch fixes it
commit af6932d6c068361c6ae300d52e72fbe13f8e1f18
Author: Simon Peyton Jones <simon.peytonjones@gmail.com>
Date: Mon Jan 8 10:49:49 2024 +0000
Make TYPE and CONSTRAINT not-apart
Issue #24279 showed up a bug in the logic in GHC.Core.Unify.unify_ty
which is supposed to make TYPE and CONSTRAINT be not-apart.
* Then !10479 implemented "unary classes".
* That change in turn allows us to make Type and Constraint apart again,
cleaning up the compiler and allowing a little bit more expressiveness.
It fixes the original hope in #24279, namely that `Type` and `Constraint`
should be distinct throughout.
-
c0a1e574
by Georgios Karachalias at 2025-11-15T05:14:31-05:00
Report all missing modules with -M
We now report all missing modules at once in GHC.Driver.Makefile.processDeps,
as opposed to only reporting a single missing module. Fixes #26551.
-
c9fa3449
by Sylvain Henry at 2025-11-15T05:15:26-05:00
JS: fix array index for registers
We used to store R32 in h$regs[-1]. While it's correct in JavaScript,
fix this to store R32 in h$regs[0] instead.
-
9e469909
by Sylvain Henry at 2025-11-15T05:15:26-05:00
JS: support more than 128 registers (#26558)
The JS backend only supported 128 registers (JS variables/array slots
used to pass function arguments). It failed in T26537 when 129
registers were required.
This commit adds support for more than 128 registers: it is now limited to
maxBound :: Int (compiler's Int). If we ever go above this threshold the
compiler now panics with a more descriptive message.
A few built-in JS functions were assuming 128 registers and have been
rewritten to use loops. Note that loops are only used for "high"
registers that are stored in an array: the 31 "low" registers are still
handled with JS global variables and with explicit switch-cases to
maintain good performance in the most common cases (i.e. few registers
used). Adjusting the number of low registers is now easy: just one
constant to adjust (GHC.StgToJS.Regs.lowRegsCount).
No new test added: T26537 is used as a regression test instead.
-
0a64a78b
by Sven Tennie at 2025-11-15T20:31:10-05:00
AArch64: Simplify CmmAssign and CmmStore
The special handling for floats was fake: The general case is always
used. So, the additional code path isn't needed (and only adds
complexity for the reader.)
-
15b311be
by sheaf at 2025-11-15T20:32:02-05:00
SimpleOpt: refactor & push coercions into lambdas
This commit improves the simple optimiser (in GHC.Core.SimpleOpt)
in a couple of ways:
- The logic to push coercion lambdas is shored up.
The function 'pushCoercionIntoLambda' used to be called in 'finish_app',
but this meant we could not continue to optimise the program after
performing this transformation.
Now, we call 'pushCoercionIntoLambda' as part of 'simple_app'.
Doing so can be important when dealing with unlifted newtypes,
as explained in Note [Desugaring unlifted newtypes].
- The code is re-structured to avoid duplication and out-of-sync
code paths.
Now, 'simple_opt_expr' defers to 'simple_app' for the 'App', 'Var',
'Cast' and 'Lam' cases. This means all the logic for those is
centralised in a single place (e.g. the 'go_lam' helper function).
To do this, the general structure is brought a bit closer to the
full-blown simplifier, with a notion of 'continuation'
(see 'SimpleContItem').
This commit also modifies GHC.Core.Opt.Arity.pushCoercionIntoLambda to
apply a substitution (a slight generalisation of its existing implementation).
-
b33284c7
by sheaf at 2025-11-15T20:32:02-05:00
Improve typechecking of data constructors
This commit changes the way in which we perform typecheck data
constructors, in particular how we make multiplicities line up.
Now, impedance matching occurs as part of the existing subsumption
machinery. See the revamped Note [Typechecking data constructors] in
GHC.Tc.Gen.App, as well as Note [Polymorphisation of linear fields]
in GHC.Core.Multiplicity.
This allows us to get rid of a fair amount of hacky code that was
added with the introduction of LinearTypes; in particular the logic of
GHC.Tc.Gen.Head.tcInferDataCon.
-------------------------
Metric Decrease:
T10421
T14766
T15164
T15703
T19695
T5642
T9630
WWRec
-------------------------
-
b6faf5d0
by sheaf at 2025-11-15T20:32:02-05:00
Handle unsaturated rep-poly newtypes
This commit allows GHC to handle unsaturated occurrences of unlifted
newtype constructors. The plan is detailed in
Note [Eta-expanding rep-poly unlifted newtypes]
in GHC.Tc.Utils.Concrete: for unsaturated unlifted newtypes, we perform
the appropriate representation-polymorphism check in tcInstFun.
-
682bf979
by Mike Pilgrem at 2025-11-16T16:44:14+00:00
Fix #26293 Valid stack.yaml for hadrian
-
acc70c3a
by Simon Peyton Jones at 2025-11-18T16:21:20-05:00
Fix a bug in defaulting
Addresses #26582
Defaulting was doing some unification but then failing to
iterate. Silly.
I discovered that the main solver was unnecessarily iterating even
if there was a unification for an /outer/ unification variable, so
I fixed that too.
-
c12fa73e
by Simon Peyton Jones at 2025-11-19T02:55:01-05:00
Make PmLit be in Ord, and use it in Map
This MR addresses #26514, by changing from
data PmAltConSet = PACS !(UniqDSet ConLike) ![PmLit]
to
data PmAltConSet = PACS !(UniqDSet ConLike) !(Map PmLit PmLit)
This matters when doing pattern-match overlap checking, when there
is a very large set of patterns. For most programs it makes
no difference at all.
For the N=5000 case of the repro case in #26514, compiler
mutator time (with `-fno-code`) goes from 1.9s to 0.43s.
All for the price for an Ord instance for PmLit
-
41b84f40
by sheaf at 2025-11-19T02:55:52-05:00
Add passing tests for #26311 and #26072
This commit adds two tests cases that now pass since landing the changes
to typechecking of data constructors in b33284c7.
Fixes #26072 #26311
-
1faa758a
by sheaf at 2025-11-19T02:55:52-05:00
mkCast: weaken bad cast warning for multiplicity
This commit weakens the warning message emitted when constructing a bad
cast in mkCast to ignore multiplicity.
Justification: since b33284c7, GHC uses sub-multiplicity coercions to
typecheck data constructors. The coercion optimiser is free to discard
these coercions, both for performance reasons, and because GHC's Core
simplifier does not (yet) preserve linearity.
We thus weaken 'mkCast' to use 'eqTypeIgnoringMultiplicity' instead of
'eqType', to avoid getting many spurious warnings about mismatched
multiplicities.
-
55eab80d
by Sylvain Henry at 2025-11-20T17:33:13-05:00
Build external interpreter program on demand (#24731)
This patch teaches GHC how to build the external interpreter program
when it is missing. As long as we have the `ghci` library, doing this is
trivial so most of this patch is refactoring for doing it sanely.
-
08bbc028
by Rodrigo Mesquita at 2025-11-20T17:33:54-05:00
Add tests for #23973 and #26565
These were fixed by 4af4f0f070f83f948e49ad5d7835fd91b8d3f0e6 in !10417
-
6b42232c
by sheaf at 2025-11-20T17:34:35-05:00
Mark T26410_ffi as fragile on Windows
As seen in #26595, this test intermittently fails on Windows.
This commit marks it as fragile, until we get around to fixing it.
-
b7b7c049
by Andrew Lelechenko at 2025-11-21T21:04:01+00:00
Add nubOrd / nubOrdBy to Data.List and Data.List.NonEmpty
As per https://github.com/haskell/core-libraries-committee/issues/336
-
352d5462
by Marc Scholten at 2025-11-22T10:33:03-05:00
Fix haddock test runner to handle UTF-8 output
xhtml 3000.4.0.0 now produces UTF-8 output instead of escaping non-ASCII characters.
When using --test-accept it previously wrote files in the wrong encoding
because they have not been decoded properly when reading the files.
-
48a3ed57
by Simon Peyton Jones at 2025-11-25T15:33:54+00:00
Add a fast-path for args=[] to occAnalApp
In the common case of having not arguments, occAnalApp
was doing redundant work.
-
951e5ed9
by Simon Peyton Jones at 2025-11-25T15:33:54+00:00
Fix a performance hole in the occurrence analyser
As #26425 showed, the clever stuff in
Note [Occurrence analysis for join points]
does a lot of duplication of usage details. This patch
improved matters with a little fancy footwork. It is
described in the new (W4) of the same Note.
Compile-time allocations go down slightly. Here are the changes
of +/- 0.5% or more:
T13253(normal) 329,369,244 326,395,544 -0.9%
T13253-spj(normal) 66,410,496 66,095,864 -0.5%
T15630(normal) 129,797,200 128,663,136 -0.9%
T15630a(normal) 129,212,408 128,027,560 -0.9%
T16577(normal) 6,756,706,896 6,723,028,512 -0.5%
T18282(normal) 128,462,070 125,808,584 -2.1% GOOD
T18698a(normal) 208,418,305 202,037,336 -3.1% GOOD
T18730(optasm) 136,981,756 136,208,136 -0.6%
T18923(normal) 58,103,088 57,745,840 -0.6%
T19695(normal) 1,386,306,272 1,365,609,416 -1.5%
T26425(normal) 3,344,402,957 2,457,811,664 -26.5% GOOD
T6048(optasm) 79,763,816 79,212,760 -0.7%
T9020(optasm) 225,278,408 223,682,440 -0.7%
T9961(normal) 303,810,717 300,729,168 -1.0% GOOD
geo. mean -0.5%
minimum -26.5%
maximum +0.4%
Metric Decrease:
T18282
T18698a
T26425
T9961
-
f1959dfc
by Simon Peyton Jones at 2025-11-26T11:58:07+00:00
Remove a quadratic-cost assertion check in mkCoreApp
See the new Note [Assertion checking in mkCoreApp]
-
98fa0d36
by Simon Hengel at 2025-11-27T17:54:57-05:00
Fix typo in docs/users_guide/exts/type_families.rst
-
5b97e5ce
by Simon Hengel at 2025-11-27T17:55:37-05:00
Fix broken RankNTypes example in user's guide
-
fa2aaa00
by Simon Peyton Jones at 2025-11-27T17:56:18-05:00
Switch off specialisation in ExactPrint
In !15057 (where we re-introduced -fpolymoprhic-specialisation) we found
that ExactPrint's compile time blew up by a factor of 5. It turned out
to be caused by bazillions of specialisations of `markAnnotated`.
Since ExactPrint isn't perf-critical, it does not seem worth taking
the performance hit, so this patch switches off specialisation in
this one module.
-
1fd25987
by Simon Peyton Jones at 2025-11-27T17:56:18-05:00
Switch -fpolymorphic-specialisation on by default
This patch addresses #23559.
Now that !10479 has landed and #26329 is fixed, we can switch on
polymorphic specialisation by default, addressing a bunch of other
tickets listed in #23559.
Metric changes:
* CoOpt_Singleton: +4% compiler allocations: we just get more
specialisations
* info_table_map_perf: -20% decrease in compiler allocations.
This is caused by using -fno-specialise in ExactPrint.hs
Without that change we get a 4x blow-up in compile time;
see !15058 for details
Metric Decrease:
info_table_map_perf
Metric Increase:
CoOpt_Singletons
-
b7fe7445
by Matthew Pickering at 2025-11-27T17:56:59-05:00
rts: Fix a deadlock with eventlog flush interval and RTS shutdown
The ghc_ticker thread attempts to flush at the eventlog tick interval, this requires
waiting to take all capabilities.
At the same time, the main thread is shutting down, the schedule is
stopped and then we wait for the ticker thread to finish.
Therefore we are deadlocked.
The solution is to use `newBoundTask/exitMyTask`, so that flushing can
cooperate with the scheduler shutdown.
Fixes #26573
-
1d4a1229
by sheaf at 2025-11-27T17:58:02-05:00
SimpleOpt: don't subst in pushCoercionIntoLambda
It was noticed in #26589 that the change in 15b311be was incorrect:
the simple optimiser carries two different substitution-like pieces of
information: 'soe_subst' (from InVar to OutExpr) and 'soe_inl'
(from InId to InExpr). It is thus incorrect to have 'pushCoercionIntoLambda'
apply the substitution from 'soe_subst' while discarding 'soe_inl'
entirely, which is what was done in 15b311be.
Instead, we change back pushCoercionIntoLambda to take an InScopeSet,
and optimise the lambda before calling 'pushCoercionIntoLambda' to avoid
mixing InExpr with OutExpr, or mixing two InExpr with different
environments. We can then call 'soeZapSubst' without problems.
Fixes #26588 #26589
-
84a087d5
by Sylvain Henry at 2025-11-28T17:35:28-05:00
Fix PIC jump tables on Windows (#24016)
Avoid overflows in jump tables by using a base label closer to the jump
targets. See added Note [Jump tables]
-
82db7042
by Zubin Duggal at 2025-11-28T17:36:10-05:00
rts/linker/PEi386: Copy strings before they are inserted into LoadedDllCache. The original strings are temporary and might be freed at an arbitrary point.
Fixes #26613
-
ff3f0d09
by Ben Gamari at 2025-11-29T18:34:28-05:00
gitlab-ci: Run ghcup-metadata jobs on OpenCape runners
This significantly reduces our egress traffic
and makes the jobs significantly faster.
-
ef0dc33b
by Matthew Pickering at 2025-11-29T18:35:10-05:00
Use 'OsPath' in getModificationTimeIfExists
This part of the compiler is quite hot during recompilation checking in
particular since the filepaths will be translated to a string. It is
better to use the 'OsPath' native function, which turns out to be easy
to do.
-
fa3bd0a6
by Georgios Karachalias at 2025-11-29T18:36:05-05:00
Use OsPath in PkgDbRef and UnitDatabase, not FilePath
-
0d7c05ec
by Ben Gamari at 2025-12-01T03:13:46-05:00
hadrian: Place user options after package arguments
This makes it easier for the user to override the default package
arguments with `UserSettings.hs`.
Fixes #25821.
-------------------------
Metric Decrease:
T14697
-------------------------
-
3b2c4598
by Vladislav Zavialov at 2025-12-01T03:14:29-05:00
Namespace-specified wildcards in import/export lists (#25901)
This change adds support for top-level namespace-specified wildcards
`type ..` and `data ..` to import and export lists.
Examples:
import M (type ..) -- imports all type and class constructors from M
import M (data ..) -- imports all data constructors and terms from M
module M (type .., f) where
-- exports all type and class constructors defined in M,
-- plus the function 'f'
The primary intended usage of this feature is in combination with module
aliases, allowing namespace disambiguation:
import Data.Proxy as T (type ..) -- T.Proxy is unambiguously the type constructor
import Data.Proxy as D (data ..) -- D.Proxy is unambiguously the data constructor
The patch accounts for the interactions of wildcards with:
* Imports with `hiding` clauses
* Import warnings -Wunused-imports, -Wdodgy-imports
* Export warnings -Wduplicate-exports, -Wdodgy-exports
Summary of the changes:
1. Move the NamespaceSpecifier type from GHC.Hs.Binds to GHC.Hs.Basic,
making it possible to use it in more places in the AST.
2. Extend the AST (type: IE) with a representation of `..`, `type ..`,
and `data ..` (constructor: IEWholeNamespace). Per the proposal, the
plain `..` is always rejected with a dedicated error message.
3. Extend the grammar in Parser.y with productions for `..`, `type ..`,
and `data ..` in both import and export lists.
4. Implement wildcard imports by updating the `filterImports` function
in GHC.Rename.Names; the logic for IEWholeNamespace is roughly
modeled after the Nothing (no explicit import list) case.
5. Implement wildcard exports by updating the `exports_from_avail`
function in GHC.Tc.Gen.Export; the logic for IEWholeNamespace is
closely modeled after the IEModuleContents case.
6. Refactor and extend diagnostics to report the new warnings and
errors. See PsErrPlainWildcardImport, DodgyImportsWildcard,
PsErrPlainWildcardExport, DodgyExportsWildcard,
TcRnDupeWildcardExport.
Note that this patch is specifically about top-level import/export
items. Subordinate import/export items are left unchanged.
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c71faa76
by Luite Stegeman at 2025-12-01T03:16:05-05:00
rts: Handle overflow of ELF section header string table
If the section header string table is stored in a section greater
than or equal to SHN_LORESERVE (0xff00), the 16-bit field e_shstrndx
in the ELF header does not contain the section number, but rather
an overflow value SHN_XINDEX (0xffff) indicating that we need to look
elsewhere.
This fixes the linker by not using e_shstrndx directly but calling
elf_shstrndx, which correctly handles the SHN_XINDEX value.
Fixes #26603
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ab20eb54
by Mike Pilgrem at 2025-12-01T22:46:55+00:00
Re CLC issue 292 Warn GHC.Internal.List.{init,last} are partial
Also corrects the warning for `tail` to refer to `Data.List.uncons` (like the existing warning for `head`).
In module `Settings.Warnings`, applies `-Wno-x-partial` to the `filepath`, and `parsec` packages (outside GHC's repository).
Also bumps submodules.
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fc1d7f79
by Jade Lovelace at 2025-12-02T11:04:09-05:00
docs: fix StandaloneKindSignatures in DataKinds docs
These should be `type` as otherwise GHC reports a duplicate definition
error.
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c25e151a
by Teo Camarasu at 2025-12-03T18:03:31+00:00
Add explicit export list to GHC.Num
Let's make clear what this module does export to allow us to easily deprecate and remove some of these in the future. Resolves https://gitlab.haskell.org/ghc/ghc/-/issues/26625