-
1f67ad21
by Andrei Borzenkov at 2024-12-25T01:42:31-05:00
Flip the order of arguments of setField (#24668)
GHC Proposal 583 "HasField redesign" specifies the
following order of a setField function arguments as this:
setField :: forall fld a b. SetField fld a b. b -> a -> a
This patch flips the application order to match the spec.
-
3e0c948d
by Ben Gamari at 2024-12-25T01:43:08-05:00
rel-eng/upload: Add set_symlink mode
This slightly eases updating of the `latest` symlinks.
-
63d63f9d
by Simon Peyton Jones at 2024-12-25T01:43:45-05:00
Preserve orientation when unifying kinds
This MR fixes yet another manifestation of the trickiness caused
by Note [Fundeps with instances, and equality orientation].
I wish there was a more robust way to do this, but this fix is
a definite improvement.
Fixes #25597
-
94ba9a6a
by ARATA Mizuki at 2024-12-26T10:47:57-05:00
x86 NCG SIMD: Support pack/insert/broadcast/unpack of 128-bit integer vectors
-
6bf0d587
by Andrew Lelechenko at 2024-12-26T10:48:33-05:00
docs: fix haddock formatting in Control.Monad.Fix
-
feb14af1
by Sergey Vinokurov at 2024-12-27T15:06:28+00:00
Remove unnecessary irrefutable patterns from NonEmpty functions
Implementation of https://github.com/haskell/core-libraries-committee/issues/107
-
6a0d91b4
by Sergey Vinokurov at 2024-12-27T15:06:28+00:00
Make cons, Semigroup, IsList, and Monad instances stricter
-
1249e597
by Sergey Vinokurov at 2024-12-27T15:06:28+00:00
Restore some laziness in <| and Semigroup instance, improve Monad instance
The Monad instance shouldn't produce the outer :| unless f a reduces
to WHNF. (Notice that the b :| bs match is implicitly lazy.)
-
8699d826
by Sergey Vinokurov at 2024-12-27T15:12:30+00:00
Add comment outlining Data.List.NonEmpty implementation guiding principles
-
7febe00e
by Sergey Vinokurov at 2024-12-27T22:24:43+00:00
Fix tests since location of ‘>>=’ changed
-
a928c326
by ARATA Mizuki at 2024-12-28T03:06:14-05:00
Fix LLVM version detection
With a recent LLVM, `llc -version` emits the version on the first line
if the vendor is set. It emits the version on the second line
otherwise.
Therefore, we need to check the both lines to detect the version.
GHC now emits a warning if it fails to detect the LLVM version,
so we can notice if the output of `llc -version` changes in the future.
Also, the warning for using LLVM < 10 on s390x is removed, because
we assume LLVM >= 13 now.
This fixes the definition of __GLASGOW_HASKELL_LLVM__ macro.
Fixes #25606
-
7f79257a
by Zubin Duggal at 2024-12-29T13:04:35+00:00
Bump base, ghc-prim and template-haskell versions for 9.12
Also bump various submodules.
(cherry picked from commit 6fc1fa3bdc8f53acdb19e47145789274060e498f)
Bump base bound to 4.21 for GHC 9.12
(cherry picked from commit 473a201c6b55aea5bf9c9db0836a66ea1b657e04)
Bump binary submodule to 0.8.9.2
(cherry picked from commit 7199869a52ab45e8856658248bf807954d58cc20)
(cherry picked from commit ec2f40b45c1a3d82d17a2fc07e9ddb9218bc3940)
Bump exceptions submodule to 0.10.9
(cherry picked from commit f5b5d1dc2d326368e5b173d622630d77f019b629)
Bump file-io submodule to 0.1.4
(cherry picked from commit ba786681de6ac5fa49938e2cd71a5988f0f40d1f)
bump os-string submodule to 2.0.6
(cherry picked from commit 3a7ffdbb832c045a55fd1ef24f546abdd9d9e30f)
bump transformers submodule to 0.6.1.2
(cherry picked from commit 53b46fd437421b9e5a001edc6d1c427439d7714f)
Bump directory submodule to v1.3.9.0
(cherry picked from commit 27dc2664c5404bb462092bb216c2c37b418fd1f8)
Bump Win32 submodule to v2.14.1.0
(cherry picked from commit 80df88086180f5e39212b2feacf70a9d2b263c6c)
Bump filepath submodule to 1.5.3.0
(cherry picked from commit 29bfae2c58a7303a081a6e7956b9f55e5faf3eeb)
Bump file-io submodule to avoid usage of QuasiQuotes
(cherry picked from commit 97b0dff223a6c4cc003adec448104c277f214645)
Bump unix submodule to 2.8.6.0
(cherry picked from commit a1f56d6d6a99c100f88ef0a8b4d51298cf24a42d)
Bump os-string submodule to 2.0.8
(cherry picked from commit 0121b76fd52ea0c0ce5d07085bc195666b63c625)
Bump file-io submodule to avoid usage of QuasiQuotes
(cherry picked from commit 962ceb50c8a6fc370e1c0a267f5cd5562a8cf759)
Bump filepath submodule to 1.5.4.0
(cherry picked from commit 7bc6877fd5d41c6d5900678ad5e73ed30f366569)
Bump file-io submodule to 0.1.5
(cherry picked from commit 9478b5aefe2877d58baf527edcf936dddbb955b7)
Bump Cabal submodule to 3.14.1.0
(cherry picked from commit 5c9c3e3f79a79bb6d9a77a17c716dc3a0bcbd2aa)
Bump directory submodule to 0.12.2.0
(cherry picked from commit 897906265db37af34ae2aaa016cec417f263407b)
Bump array submodule for base bump
Bump stm submodule for base bump
Bump process submodule for base bump
-
f6079408
by Zubin Duggal at 2024-12-29T13:04:35+00:00
Fix ghc-e005 after HasCallstack changes
(cherry picked from commit 77f340a24561cea8a6f2ada296b3ea356ab1823c)
-
3e10fa75
by Zubin Duggal at 2024-12-29T13:04:35+00:00
Add haskeline to stage0Packages
Otherwise we link against boot inplace and boot unix as boot haskeline
depends on boot unix.
(cherry picked from commit 90b493769ebdf3cd7be404d18462dc20ac1044df)
-
4ad6aec4
by Zubin Duggal at 2024-12-29T13:04:35+00:00
Fix TH changelog
-
ea3f7fd5
by Zubin Duggal at 2024-12-29T13:04:35+00:00
release: copy index.html from correct directory
(cherry picked from commit cbfd0829cd61928976c9eb17ba4af18272466063)
-
fafb70db
by Zubin Duggal at 2024-12-29T13:04:35+00:00
hadrian-multi: warn on unused imports
os-string has redundant imports
(cherry picked from commit dde3796be689ea57543936e22aa5ea4ef7ed995e)
-
c02b1e46
by Simon Peyton Jones at 2024-12-29T17:04:30-05:00
Fix in-scope set for CSE
Ticket #25468 showed an assertion failure in CSE because a top-level
Id was being used before it was defined. Reason: Note [Glomming] in
GHC.Core.Opt.OccurAnal.
Solution (used in many places): just put all the top-level bindings in
scope at the beginning of CSE.
Compile-time allocation wobbles up and down a tiny bit; geo mean is
zero. But MultiLayerModulesTH_OneShot and hard_hole_fits increase (on
some architectures only) by a bit oever 2% . I think these are just a
random fluctuations.
Metric Increase:
MultiLayerModulesTH_OneShot
hard_hole_fits
-
559d4f84
by Krzysztof Gogolewski at 2024-12-30T11:53:19-05:00
Add tests for #23883
The issue has been fixed by commit f5d3e03c56ffc63.
Only T23883a is the actual regression test, the remaining ones are
tricky cases found during development of an independent fix !11313.
-
278a53ee
by Sergey Vinokurov at 2024-12-30T11:53:59-05:00
Update changelog for CLC proposal #107 (NonEmpty laziness)
-
f56558be
by Matthew Pickering at 2025-01-07T13:53:03-05:00
warnings: Find out if a qualified name is in the interactive scope directly
There were two ad-hoc mechanisms used to determine which modules were in
the interactive scope.
1. Look at everything in the GRE, to see what is imported qualified.
2. Look at the last loaded module in the HPT.
(1) Is very inefficient, GlobalRdrEnvs can be very big.
(2) is incorrect, there is no reason to assume the "last" thing added to
the HPT has any relevance to module loading order.
Happily, the same checks can be implemented directly by looking at the
interactive imports from the interactive context. This mirrors what
happens for normal imports.
Arguably, the error reporting code shouldn't be doing this kind of
processing and it should be an option is set when rendering the error
message. However, this just improves the situation and doesn't block
progress on that front in future.
See #14225 and #15611
Fixes #25600
-
84155cdb
by Simon Peyton Jones at 2025-01-07T13:53:40-05:00
Tidy up kcConDecls
Addresses #25630
In particular,
* Introduce ConArgKind and use it.
* Make kcConDecls and tcConDecls work the same way
concerning the kind of argument types
-
6c12b6cf
by Bryan Richter at 2025-01-07T18:15:02-05:00
Remove tmp files after toolchain check
Fixes #25620
-
42826a89
by Cheng Shao at 2025-01-07T18:15:39-05:00
xxhash: bump to v0.8.3
-
185f17e4
by sheaf at 2025-01-07T18:16:15-05:00
Fix typo in GHC.Tc.Solver.Solve.runTcPluginsWanted
-
23099752
by Luite Stegeman at 2025-01-08T00:33:33+01:00
Add flags for switching off speculative evaluation.
We found that speculative evaluation can increase the amount of
allocations in some circumstances. This patch adds new flags for
selectively disabling speculative evaluation, allowing us to
test the effect of the optimization.
The new flags are:
-fspec-eval
globally enable speculative evaluation
-fspec-eval-dictfun
enable speculative evaluation for dictionary functions (no effect
if speculative evaluation is globally disabled)
The new flags are on by default for all optimisation levels.
See #25284
-
0161badc
by Ben Gamari at 2025-01-09T17:30:05-05:00
rts/printClosure: Print IPE information for thunks and functions
This makes it considerably easier to grok the structure of the heap
when IPE information is available.
-
023f36f5
by Rodrigo Mesquita at 2025-01-10T14:57:48-05:00
user_guide: Note -pgmP/-optP are for /Haskell/-CPP
Fixes #25574
-
e1c133f2
by Ben Gamari at 2025-01-10T14:58:25-05:00
dump-decls: Suppress unit-ids
While the testsuite driver already normalizes these away, they are
nevertheless a severe nuisance when diffing outside of the testsuite.
Intriguingly, this doesn't completely eliminate the unit IDs; some
wired-in names are still printed. However, this is a cheap and helpful
improvement over the status quo so I am simply going to accept this.
Fixes #25334.
-
2e7bf446
by sheaf at 2025-01-13T10:55:26+01:00
Remove SDocs from ErrCtxt & ErrInfo
This commit:
- turns the SDoc used in ErrCtxt into a proper error datatype,
ErrCtxtMsg, which contains all the different error contexts that
can be added,
- replaces ErrInfo with [ErrCtxt].
ErrInfo used to contain two SDocs; the first is replaced with [ErrCtxt],
and the second is removed, with the relevant information being put
in the appropriate error message constructors.
Fixes #23436
-
2d62b970
by Mike Pilgrem at 2025-01-13T12:59:10-05:00
Re CLC #300 - Specify fmap for NonEmpty as map
See:
* https://github.com/haskell/core-libraries-committee/issues/300
Seeks to:
* move existing instances for NonEmpty (except of Eq and Ord) out of GHC.Internal.Base into new GHC.Internal.Data.NonEmpty (to avoid otherwise unavoidable cycles in the module graph);
* move map out of Data.List.NonEmpty (base package) into GHC.Internal.Data.NonEmpty;
* define fmap as map for NonEmpty instance of Functor, avoiding code duplication;
* re-export map from existing GHC.Internal.Data.List.NonEmpty; and
* re-export map from Data.List.NonEmpty (base package);
without breaking anything in the GHC repository.
Various tests *.stdout and *.stderr files are amended also.
-
ab3ab3e3
by Luite Stegeman at 2025-01-13T12:59:58-05:00
compiler/coreprep: Turn off dictionary speculation by default
Speculative evaluation can cause performance regressions,
therefore we turn it off by default. It can be enabled again
with the -fspec-eval-dictfun flag
See #25284
-
3d9cacd5
by Patrick at 2025-01-14T02:34:46+08:00
Enhance kind inference for data family instances
This commit improves kind inference for data family instances by kind-checking
the constructors, for H98 and newtype declarations (ONLY), as well as
kind-checking the result kind signature (when using GADT syntax).
This fixes #25611.
Typechecker changes:
In `tcDataFamInstHeader`, we now kind-check the constructors using
`kcConDecls`, for H98-style decls and newtype decls ONLY.
See Note [Kind inference for data family instances].
Testsuite changes:
- The T25611{a,b,c,d} tests test the new kind inference implementation.
- a,b: infer result kind from constructors (H98 case)
- c: renamed version of test UnliftedNewtypesUnassociatedFamilyFail,
which now passes
- d: GADT case, checking that we don't infer overly rigid kinds when
kind-checking the constructors in data family instances.
- DataInstanceKindsDefaults tests defaulting data instance kinds
without UnliftedNewtypes or UnliftedDatatypes, as outlined in
Note [Defaulting result kind of newtype/data family instance].
Also a few notes are updated to reflect the changes.
Co-authored-by: default avatarSimon Peyton Jones <simon.peytonjones@gmail.com>
-
f6493dbc
by amesgen at 2025-01-15T18:47:23-05:00
wasm: prevent bundlers from resolving import("node:timers")
This fixes the following esbuild error:
✘ [ERROR] Could not resolve "node:timers"
www/ghc_wasm_jsffi.js:66:25:
66 │ return (await import("node:timers")).setImmediate;
╵ ~~~~~~~~~~~~~
The package "node:timers" wasn't found on the file system but is built into node. Are you trying
to bundle for node? You can use "--platform=node" to do that, which will remove this error.
Previously (i.e. after !13503), one had to work around this by passing
`--external:node:timers`.
-
87e82e2e
by sheaf at 2025-01-16T14:51:45+01:00
Use checkTyEqRhs to make types concrete
This commit refactors makeTypeConcrete to call checkTyEqRhs with
the appropriate parameters. This avoids duplicating subtle logic
in two places in the compiler.
Changes:
1. Refactor of 'TyEqFlags'. Now 'TyEqFlags' stores a 'TEFTask', which
is a description of which of the following checks we want to
perform in 'checkTyEqRhs':
- occurs check
- level check
- concreteness check
In the process, the 'AreUnifying' datatype has been removed, as it
is no longer needed.
2. Refactor of 'checkTyVar':
a. Make use of the new 'TEFTask' data type to decide which checks
to perform.
In particular, this ensures that we perform **both** a
concreteness check and a level check when both are required;
previously we only did a concreteness check (that was a bug!).
b. Recursively call 'checkTyVar' on the kind of unfilled
metavariables. This deals with a bug in which we failed to
uphold the invariant that the kind of a concrete type must
itself be concrete. See test cases T23051, T23176.
3. Re-write of 'makeTypeConcrete', which now simply calls
'checkTyEqRhs' with appropriate 'TyEqFlags'/'TEFTask'.
This gets rid of code duplication and risk for the two code paths
going out-of-sync.
Fixes #25616. See also #23883.
-
5a8f35bd
by ARATA Mizuki at 2025-01-17T11:17:49-05:00
x86 NCG: Use correct format for MOVD in the implementation of unpackInt64X2#
MOVD takes the input format.
Fixes #25658
-
14f8a7ec
by Mateusz Goślinowski at 2025-01-17T22:49:09+00:00
Allow multiline strings in JS FFI (#25633)
-
854c2f75
by Simon Peyton Jones at 2025-01-18T02:54:08-05:00
Fix a buglet in tcSplitForAllTyVarsReqTVBindersN
The problem was that an equation in `split` had two guards (one about
visiblity and one about `n_req`). So it fell thorugh if /either/
was False. But the next equation then assumed an invisible binder.
Simple bug, easily fixed. Fixes #25661.
-
264a1186
by sheaf at 2025-01-18T10:05:56+00:00
Generalise GHC diagnostic code infrastructure
This commit generalises the infrastructure used for diagnostic codes,
allowing it to be used for other namespaces than the GHC namespace.
In particular, this enables GHCi to re-use the same infrastructure to
emit error messages.
-
bf4f5ad3
by Jade at 2025-01-18T10:05:56+00:00
Add structured errors to GHCi (#23338)
This patch creates the 'GhciCommandErrorMessage' data type which
implents the 'Diagnostic' class and also provides error code for these
error conditions.
-
b6f54188
by Ben Gamari at 2025-01-18T12:38:46-05:00
Revert "Division by constants optimization"
This appears to be responsible for the regression described in #25653.
This reverts commit daff1e30219d136977c71f42e82ccc58c9013cfb.
-
0fd90de8
by Ben Gamari at 2025-01-18T12:38:46-05:00
testsuite: Introduce div2 test
This is a useful test from !8392 which is worth keeping around.
-
32680979
by Ben Gamari at 2025-01-18T12:38:46-05:00
testsuite: Test shift correctness in mul2 test
-
163aa50a
by Ben Gamari at 2025-01-18T12:38:46-05:00
testsuite: Add regression test for #25653
-
44778963
by Matthew Pickering at 2025-01-20T11:23:08+00:00
driver: Store an ExternalModuleGraph in the EPS
We now store an ExternalModuleGraph in the EPS. When an new interface is
loaded, the module graph is extended with a node for the loaded
interface. The result is a partial module graph. If you want to run
a transitive closure query on the graph you must first force the
transitive closure to be loaded by using `loadExternalGraphBelow`.
The primary advantage (for now) is that the transitive dependency
calculation does not have to be repeated in getLinkDeps. If your module
had many dependencies and many splices, performing this calculation at
every splice site took a significant amount of time.
We might also want to use this module graph in future for considering
questions such as reachability of rules or accessibilty of instance
imported by levelled imported.
This patch removes another place in the compiler where transitive
dependency is calculated in an ad-hoc manner. In general, the transitive
dependency calculation should be cached and computed using a ModuleGraph
abstraction.
The transitive dependency query required by getLinkDeps operates on a
graph without hs-boot nodes. If a linkable from a module in a loop is
needed, then all modules in the loop are necessary to be available to
execute that module. Therefore there is a query in `ModuleGraph` and
`ExternalModuleGraph` which allows a transitive closure query to be
performed on a graph without loops.
Fixes #25634
-------------------------
Metric Decrease:
MultiLayerModulesTH_Make
MultiLayerModulesTH_OneShot
Metric Increase:
mhu-perf
-------------------------
Co-authored-by: Rodrigo Mesquita <rodrigo.m.mesquita@gmail.com>
-
b3c0acfc
by Cheng Shao at 2025-01-20T11:53:10-05:00
hie: fix hie.yaml to use default hie-bios script
!13778 accidentally changed hie.yaml to use hie-bios.bat as the
default hie-bios script, which completely breaks hie support on
non-Windows platforms. This patch reverts that change.
-
595013d4
by Ben Gamari at 2025-01-21T09:57:23-05:00
compiler: Fix CPP guards around ghc_unique_counter64
The `ghc_unique_counter64` symbol was introduced in the RTS in the
64-bit unique refactor (!10568) which has been backported to %9.6.7 and
%9.8.4. Update the CPP to reflect this.
Fixes #25576.
-
09ee3247
by Ryan Scott at 2025-01-21T09:58:00-05:00
Fix :info pretty-printing of UNPACKed fields
This patch:
* Ensures that we do not pretty-print a field like `foo :: {-# UNPACK #-} !Int`
as `foo :: ! {-# UNPACK -#} Int` (as we were doing before) when running the
`:info` command.
* Prevents coercions that arise from `UNPACK`ed fields (e.g., such as when one
unpacks a newtype) from being printed in `:info` output unless `-dppr-debug`
is enabled.
Fixes #25651.
-
6b7ea592
by Rodrigo Mesquita at 2025-01-21T16:10:35-05:00
driver: Store the HomePackageTable in a mutable reference
This commit refactors the HomePackageTable and HomeUnitGraph:
(1) It fixes a quadratic-in-the-number-of-modules space leak in upsweep (#25511)
(2) And it reworks these structures into their own modules to simplify
the driver. The refactor is driven by the introduction of IO in the HPT
interface, but is a bit more aggressive in simplifying the
interfaces to enforce correct usage (ie to avoid performance
pitfalls).
Specifically:
- The `HomeUnitGraph` (HUG) is now in `GHC.Unit.Home.Graph`
- The `HomePackageTable` (HPT) is now in `GHC.Unit.Home.PackageTable`
- The HPT now stores an `IORef` with the table of loaded home package modules.
- The interface to the HPT now requires IO
- The interface now enforces that the HPT is a datastructure that
only grows
- This is not enforced in the interface, but, clients of the HPT
should never care about there being more or less entries in the
HPT when these additional entries are not relevant to their result.
- The exception to the invariant that the HPT is monotonically
increasing is `restrictHpt`, a function which is called at a
"barrier point" (during which there are no other threads
inspecting or inserting in the HPT). The invariant can be
temporarily broken at this point (currently, after upsweep).
This is safe because a single thread holds control over the
structure (thus the invariant being broken is never observed).
The hug_var and associated structures in the driver, which aimed to
improve memory usage in the driver by updating in place a HUG during
upsweep, are no longer required as the HPT entries in the HUG are now
themselves mutable by construction. This was previously explained in
Note [ModuleNameSet, efficiency and space leaks], which is no longer
relevant and was deleted.
Fixes #25511
Co-authored-by: Matthew Pickering <matthewtpickering@gmail.com>
-------------------------
Metric Decrease:
MultiComponentModulesRecomp
MultiLayerModulesRecomp
-------------------------
-
f983a00f
by Jens Petersen at 2025-01-21T16:11:12-05:00
hp2ps/Utilities.c: add extern parameter types for malloc and realloc for C23
Fix build with gcc-15 which defaults to C23 standard (-std=gnu23)
Fixes #25662
```
utils/hp2ps/Utilities.c:6:14: error:
warning: conflicting types for built-in function ‘malloc’; expected ‘void *(long unsigned int)’ [-Wbuiltin-declaration-mismatch]
6 | extern void* malloc();
| ^~~~~~
|
6 | extern void* malloc();
| ^
utils/hp2ps/Utilities.c:5:1: error:
note: ‘malloc’ is declared in header ‘<stdlib.h>’
4 | #include "Error.h"
+++ |+#include <stdlib.h>
5 |
|
5 |
| ^
utils/hp2ps/Utilities.c: In function ‘xmalloc’:
utils/hp2ps/Utilities.c:80:17: error:
error: too many arguments to function ‘malloc’; expected 0, have 1
80 | r = (void*) malloc(n);
| ^~~~~~ ~
|
80 | r = (void*) malloc(n);
| ^
utils/hp2ps/Utilities.c:6:14: error:
note: declared here
6 | extern void* malloc();
| ^~~~~~
|
6 | extern void* malloc();
| ^
utils/hp2ps/Utilities.c: In function ‘xrealloc’:
utils/hp2ps/Utilities.c:92:18: error:
warning: conflicting types for built-in function ‘realloc’; expected ‘void *(void *, long unsigned int)’ [-Wbuiltin-declaration-mismatch]
92 | extern void *realloc();
| ^~~~~~~
|
92 | extern void *realloc();
| ^
utils/hp2ps/Utilities.c:92:18: error:
note: ‘realloc’ is declared in header ‘<stdlib.h>’
|
92 | extern void *realloc();
| ^
utils/hp2ps/Utilities.c:94:9: error:
error: too many arguments to function ‘realloc’; expected 0, have 2
94 | r = realloc(p, n);
| ^~~~~~~ ~
|
94 | r = realloc(p, n);
| ^
utils/hp2ps/Utilities.c:92:18: error:
note: declared here
92 | extern void *realloc();
| ^~~~~~~
|
92 | extern void *realloc();
| ^
```
-
51e3ec83
by Vladislav Zavialov at 2025-01-22T20:41:32+03:00
Rework built-in and punned names (#25174, #25179, #25180, #25182)
This patch rewrites part of the logic for dealing with built-in and
punned names, making it more principled and fixing a few bugs.
* Kill off filterCTuple. Its purpose was to improve pretty-printing of
constraint tuples, and the appropriate place for this is namePun_maybe.
* Remove unitTyCon, unboxedUnitTyCon, and soloTyCon from wiredInTyCons.
Their inclusion in the list was a workaround for shoddy logic in
lookupOrigNameCache. Now we treat tuples of all arities uniformly.
* In isBuiltInOcc_maybe, only match on actual built-in syntax, e.g. "FUN"
shouldn't be there (#25174). Also take ListTuplePuns into account (#25179).
* When matching OccNames, use the ShortByteString directly to avoid
potentially costly conversions to ByteString and String.
* Introduce isInfiniteFamilyOrigName_maybe, a purpose-built helper for
looking up tuples/sums in the OrigNameCache. This clears up the previously
convoluted relation between the orig name cache and built-in syntax.
* Reuse isKnownOrigName_maybe to eliminate the need for isPunOcc_maybe.
* Classify MkSolo and MkSolo# as UserSyntax, thus fixing whole-module
reexports (#25182).
* Teach valid-hole-fits about tuples, unboxed tuples, and unboxed sums,
up to a certain arity (#25180).
* Drop the unnecessary special case for unary constraint tuples in the
type checker (finish_tuple). It was a workaround for the lack of CSolo.
* Update Notes and other comments, add tests.
-
85c60aea
by Teo Camarasu at 2025-01-23T18:06:21-05:00
doc: Add documentation for -XDoAndIfThenElse
Resolves #18631
Co-authored-by: Richard Eisenberg <rae@cs.brynmawr.edu>
-
4495e48f
by Brandon Chinn at 2025-01-24T11:54:24-05:00
Break out GHC.Parser.Lexer.Interface
-
4f8fc11e
by Brandon Chinn at 2025-01-24T11:54:24-05:00
Fix lexing comments in multiline strings (#25609)
Metric Decrease:
MultiLayerModulesRecomp
parsing001
-
e7ab778f
by Matthew Pickering at 2025-01-24T11:55:01-05:00
testsuite: Pass TEST_HC_OPTS to many more tests
This passes `-dno-debug-output` to the test and `-dlint.
-
c3593101
by Sylvain Henry at 2025-01-24T23:12:20-05:00
Merge ghc-prim's modules into ghc-internal (#24453)
ghc-internal becomes the only wired-in package exposing primitives.
There are some minor GHC allocation regressions, but they barely cross
the thresholds and only with the wasm backend. They're likely due to
longer symbols (ghc-internal vs ghc-prim, GHC.Internal.X vs GHC.X).
Metric Increase:
T13035
T1969
T4801
T9961
-
70f7741a
by Jens Petersen at 2025-01-24T23:12:58-05:00
hp2ps/Utilities.c: add extern parameter types for malloc and realloc for C23
use portable C types!
-
a1d92378
by Brandon Chinn at 2025-01-25T15:11:54-08:00
Fix for alex-3.5.2.0 (#25623)
This INLINE pragma for alexScanUser was added in 9.12, but then I
ported the change to alex in 3.5.2.0
(https://github.com/haskell/alex/pull/262).
I didn't realize that GHC errors on duplicate INLINE pragmas, so
this ended up being a breaking change.
This change should be backported into 9.12
-
62760367
by ARATA Mizuki at 2025-01-27T16:23:06-05:00
x86 NCG: Make MOVD's output format explicit
The old design led to inference of a wrong format,
losing upper bits of a vector register.
Fixes #25659
Co-authored-by: sheaf <sam.derbyshire@gmail.com>
-
f19ab490
by Simon Hengel at 2025-01-27T16:23:45-05:00
doc: Correct JSON schema for `-fdiagnostics-as-json` (fixes #25393)
-
e16eae65
by Cheng Shao at 2025-01-27T21:41:39+00:00
hadrian: fix bootstrap with 9.12.1
This patch bumps hadrian index-state to fix bootstrap with 9.12.1.
-
8071bad8
by Jeffrey Young at 2025-01-28T21:45:32-05:00
base: add SrcLoc changes to changelog, 4.21.0.0
I accidentally dropped this in !13381
- closes #25614
See:
- ea4587794b9e3a098f9c02bd6cea2294af2539ce (the 13381 commit)
- Issue #25614
-
9dcc7e28
by M Farkas-Dyck at 2025-01-29T02:27:48-05:00
Rename `cloneBndrs` and such — now all the monadic ones have an `M` suffix.
We now have `cloneBndrs` and `cloneRecIdBndrs` which take a `UniqSupply` argument, and `cloneBndrsM` and `cloneRecIdBndrsM` which rather have a `MonadUnique` constraint.
-
643dd3d8
by Matthew Farkas-Dyck at 2025-01-29T02:27:48-05:00
Use `Infinite` in unique generation, and clean up some other partial uni patterns as well.
Also drop the losing `instance MonadFail UniqSM`.
We redefine `getUniquesM` in terms of `Infinite` rather than `[]`, and define another method `getUniqueListM` for the use sites where we actually want a `[]`.
Thus, at many sites, we can avoid the partiality of the empty list case.
We also define `withUniques`, `withUniquesM`, and `withUniquesM'`, which traverse an arbitrary `Traversable` structure and introduce a `Unique` for each element.
This allows us to redefine various functions to operate on more appropriate types than `[]` and avoid further partiality (in the form of incomplete-uni-patterns).
-
dd0acc3c
by M Farkas-Dyck at 2025-01-29T02:27:48-05:00
Use `Infinite` in `GHC.Tc.Deriv.Functor`.
Make the list of variables to use in generated code `Infinite`, to avoid panicking on the (now impossible) empty list case.
-
4e9adedf
by M Farkas-Dyck at 2025-01-29T02:27:48-05:00
Use `Infinite` in `GHC.Runtime.Debugger`.
Make the list of available names `Infinite`, to avoid panicking on the (now impossible) empty list case.
-
bed812b7
by M Farkas-Dyck at 2025-01-29T02:27:48-05:00
Avoid incomplete-uni-patterns in `GHC.Cmm.DebugBlock`.
We do so by changing the type of `BlockContext` to statically (in GHC) exclude the possibility of Cmm statics, and using `NonEmpty` lists of `BlockContext`s in `cmmDebugGen`.
-
27587df3
by M Farkas-Dyck at 2025-01-29T02:27:48-05:00
Avoid incomplete-uni-patterns in `GHC.Types.Literal`.
We do so by introducing `mkLitNumberWrap'` whose ultimate codomain is `Integer` rather than `Literal`, and then use that rather than `mkLitNumberWrap` where we just need the number rather than the `Literal`.
-
138de0ff
by M Farkas-Dyck at 2025-01-29T02:27:48-05:00
Avoid incomplete-uni-patterns in `GHC.CmmToAsm.X86.CodeGen`.
- Match the vector element list only once in `shuffleInstructions`.
- Define `isSuitableFloatingPointLit_maybe` which returns `Just` the width if the lit is indeed suitable.
-
d8cb3d36
by M Farkas-Dyck at 2025-01-29T02:27:48-05:00
Clean up more incomplete uni patterns.
At some sites, we merely panic if the `[]` or `Maybe` is empty when we convert to `NonEmpty` or `Identity`, but at least now we make it explicit.
At other sites, we are able to use more precise types and avoid the partiality altogether. To do so, we redefine various functions to operate over `Traversable` arguments, so we can use the appropriate shape where known.
-
f251bd22
by M Farkas-Dyck at 2025-01-29T02:27:48-05:00
Outline `expectJustPanic`.
-
a963a1a5
by Marc Scholten at 2025-01-29T02:28:35-05:00
base: Introduce Data.Enum.enumerate (CLC #306)
https://github.com/haskell/core-libraries-committee/issues/306
-
944712da
by Ben Gamari at 2025-01-29T02:29:13-05:00
base: Update description of locking behavior
-
85abc69c
by Ben Gamari at 2025-01-29T02:29:51-05:00
base: Fix @since annotation of Data.Bounded
Fixes #25615.
-
2ca41c62
by Ben Gamari at 2025-01-29T02:30:29-05:00
StgToByteCode: Fix overly-broad handling of Addr# literals
Previously we assumed that all unlifted types were `Addr#` but this
isn't true. As noted in #25638, unlifted nullary data constructor
workers can also appear at the top-level and are obviously not of type
`Addr#`.
Note that there is more work to be done to properly handle unlifted data
constructors (especially nullary; see #25636). However, this is a small
step in the right direction.
Closes #25641.
-
ec26c54d
by Ben Gamari at 2025-01-29T02:30:29-05:00
StgToByteCode: Assert that PUSH_G'd values are lifted
We currently do not support top-level unlifted data constructor applications,
therefore this is a safe assertion.
Pointed out by @sheaf.
-
8847125f
by Ben Gamari at 2025-01-29T02:31:07-05:00
gitlab-ci: Run test-primops testsuite in ~"full-ci" pipeline
Closes #25654.
-
bf8c7d6e
by Matthew Pickering at 2025-01-29T02:31:44-05:00
bytecode: Do not generate `SLIDE x 0` instructions
SLIDE x 0 is a no-op as it means to shift x elements of the stack by no
spaces. In the interpreter, this results in a loop which copies an array
element into the same place.
I have instrumented GHCi to count how many of these instructions are interpreted.
The workload was `ghc` compiling two simple modules.
Total no-op slides: 7793476
Total slides: 11413289
Percentage useless (slides): 68%
Percentage uselss of total instructions: 9%
-
7bfc93a7
by Zubin Duggal at 2025-01-29T21:41:17-05:00
hackage-doc-tarball: Allow ghc-boot-th to be uploaded to hackage
It can't refer to files outside its source directory, so patch that part out.
This is OK because those files are only used while bootstrapping.
Also add ghci to the list of packages to be uploaded
Fixes #25687
-
704eeb02
by Roman S at 2025-01-29T21:42:05-05:00
Fix Control.Arrow (***) diagram (fixes #25698)
-
662645f0
by Matthew Pickering at 2025-02-03T11:44:41-05:00
compiler: Always load GHC.Data.FastString optimised into GHCi
The FastString table is shared between the boot compiler and interpreted
compiler. Therefore it's very important the representation of
`FastString` matches in both cases. Otherwise, the interpreter will read
a FastString from the shared variable but place the fields in the wrong
place which leads to segfaults.
Ideally this state would not be shared, but for now we can always
compile both with `-O2` and this leads to a working interpreter.
-
05e5785a
by Peter Trommler at 2025-02-03T11:45:17-05:00
RTS: Fix compile on powerpc64 ELF v1
Cabal does not know about the different ABIs for powerpc64 and compiles
StgCRunAsm.S unconditionally. The old make-based build system excluded
this file from the build and it was OK to signal an error when it was
compiled accidentally.
With this patch we compile StgCRunAsm.S to an empty file, which fixes
the build.
Fixes #25700
-
cbbb64fb
by Matthew Pickering at 2025-02-03T23:40:33-05:00
interpreter: Always print unit and module name in BCO_NAME instruction
Currently the BCO_Name instruction is a bit difficult to use since the
names are not qualified by the module they come from. When you have a
very generic name such as "wildX4", it becomes impossible to work out
which module the identifier comes from.
Fixes #25694
-
764a43ac
by Ben Gamari at 2025-02-03T23:41:10-05:00
upload-ghc-libs: Drop more references to ghc-internal from ghc-boot-th
(cherry picked from commit afec4b75c2d0e9f5c462a86d9f3697acf30355c7)
Co-authored-by: Ben Gamari <bgamari.foss@gmail.com>
-
9a59b026
by Ben Gamari at 2025-02-04T10:00:18-05:00
gitlab-ci: Don't use .full-ci to run test-primops
test-primops depends upon the existence of validate jobs, yet these do
not exist in the context of nightly jobs, which .full-ci includes.
-
7cc08550
by Ben Gamari at 2025-02-04T18:34:49-05:00
CorePrep: Name `sat` binders more descriptively
-
fb40981d
by Ben Gamari at 2025-02-04T18:35:26-05:00
ghc-toolchain: Parse i686 triples
This is a moniker used for later 32-bit x86 implementations
(Pentium Pro and later).
Fixes #25691.
-
02794411
by Cheng Shao at 2025-02-04T18:36:03-05:00
compiler: remove unused assembleOneBCO function
This patch removes the unused assembleOneBCO function from the
bytecode assembler.
-
db19c8a9
by Matthew Pickering at 2025-02-05T23:16:50-05:00
perf: Replace uses of genericLength with strictGenericLength
genericLength is a recursive function and marked NOINLINE. It is not
going to specialise. In profiles, it can be seen that 3% of total compilation
time when computing bytecode is spend calling this non-specialised
function.
In addition, we can simplify `addListToSS` to avoid traversing the input
list twice and also allocating an intermediate list (after the call to
reverse).
Overall these changes reduce the time spend in 'assembleBCOs' from 5.61s
to 3.88s. Allocations drop from 8GB to 5.3G.
Fixes #25706
-
5622a14a
by Matthew Pickering at 2025-02-05T23:17:27-05:00
perf: nameToCLabel: Directly manipulate ByteString rather than going via strings
`nameToCLabel` is called from `lookupHsSymbol` many times during
bytecode linking. We can save a lot of allocations and time by directly
manipulating the bytestrings rather than going via intermediate lists.
Before: 2GB allocation, 1.11s
After: 260MB allocation, 375ms
Fixes #25719
-------------------------
Metric Decrease:
MultiLayerModulesTH_OneShot
-------------------------
-
66c7f656
by Matthew Pickering at 2025-02-06T17:15:25-05:00
interpreter: Fix INTERP_STATS profiling code
The profiling code had slightly bitrotted since the last time it was
used. This just fixes things so that if you toggle the INTERP_STATS
macro then it just works and prints out the stats.
Fixes #25695
-
f71c2835
by Matthew Pickering at 2025-02-06T17:16:02-05:00
perf: Key the interpreter symbol cache by Name rather than FastString
Profiles showed that about 0.2s was being spend constructing the keys
before looking up values in the old symbol cache.
The performance of this codepath is critical as it translates directly
to a delay when a user evaluates a function like `main` in the
interpreter.
Therefore we implement a solution which keys the cache(s) by `Name`
rather than the symbol directly, so the cache can be consulted before
the symbol is constructed.
Fixes #25731
-
8f8d3a90
by Ben Gamari at 2025-02-08T01:17:28-05:00
base: Label threads forked by IO operations
Addresses part of #25452.
Addresses core-libraries-committee#305.
-
28600825
by Ben Gamari at 2025-02-08T01:17:28-05:00
base: Label threads forked by System.Timeout
Addresses part of #25452.
Addresses core-libraries-committee#305.
-
8a249827
by Ben Gamari at 2025-02-08T01:17:28-05:00
base: Label signal handling threads
Addresses part of #25452.
Addresses core-libraries-committee#305.
-
26af26f0
by Ben Gamari at 2025-02-08T01:17:28-05:00
base: Label Windows console event handling threads
Addresses part of #25452.
Addresses core-libraries-committee#305.
-
bf9c3d4f
by Ben Gamari at 2025-02-08T01:17:28-05:00
ghci: Label evaluation sandbox thread
Addresses part of #25452.
Addresses core-libraries-committee#305.
-
38f78ce5
by Ben Gamari at 2025-02-08T01:17:28-05:00
base: Add changelog entry for addition of thread labels
Addresses #25452.
Addresses core-libraries-committee#305.
-
c100deb5
by Ben Gamari at 2025-02-08T01:18:05-05:00
gen-ci: Clean up style
This cleans up a number of stylistic inconsistencies although it's still
far from perfect.
-
c4a7680a
by Ben Gamari at 2025-02-08T01:18:05-05:00
gen-ci: Properly encapsulate GitLab predicates
-
52b6539b
by M Farkas-Dyck at 2025-02-08T11:34:51-08:00
Avoid partiality in `Language.Haskell.Syntax.Expr`, `GHC.Hs.Expr`, `GHC.Rename.Expr`, etc.
In particular, use `NonEmpty` where appropriate:
- the argument of `FieldLabelString`
- the argument of `HsMultiIf`
- `grhssGRHSs`
Decreases overall compile-time allocation by about 0.1% in the benchmark suite (min -0.8%, max +0.3%).
Metric Decrease:
T3294
-
a566da92
by Ben Gamari at 2025-02-10T03:21:49-05:00
gitlab-ci: Bump docker images
Closes #25693.
-
a7e23f01
by Ben Gamari at 2025-02-10T03:21:49-05:00
hadrian: Drop uses of head/tail
To silence warnings with GHC 9.10
-
12752f0c
by Ben Gamari at 2025-02-10T03:21:49-05:00
hadrian: Disable x-data-list-nonempty-unzip warning
-
e22a14fc
by Simon Peyton Jones at 2025-02-11T16:21:10+00:00
Deal correctly with Given CallStack constraints
As #25675 showed, the CallStack solving mechanism was failing
to account for Given CallStack constraints.
This small patch fixes it and improves the Notes.
Small improvement to GHCi debugger output in break011, break024,
which is discussed on the MR !13883
-
db3e810f
by Simon Peyton Jones at 2025-02-12T09:12:30-05:00
Fix inlineBoringOk again
This MR fixes #25713, which turned out to be a consequence of not
completing #17182.
I think I have now gotten it right. See the new
Note [inlineBoringOk]
-
ef0e6cfc
by Ben Gamari at 2025-02-17T19:20:09-05:00
testsuite: Mark T23071 and T2047 as fragile on FreeBSD
These inexplicably fail on FreeBSD on CI. Sadly I am unable to reproduce
this locally but regardless this is holding up Marge so I will mark them
as fragile for now.
Addresses #25751.
-
7596675e
by Jens Petersen at 2025-02-18T08:53:08-05:00
hp2ps Utilities.c: include stdlib.h instead of extern malloc and realloc
-
975d932c
by Rodrigo Mesquita at 2025-02-18T08:53:45-05:00
Inline join points for rhs without free vars
While investigating #25170, we ran into a program (T16473) that allocated 67%
more because of a join point that failed to inline.
Note [Duplicating join points] explains why we want to be conservative
when inlining join points, using as an example a join point that
captures a free variable `f` that becomes available in the continuation
`blah` for further optimisations, as opposed to being lambda-abstracted.
However, when the RHS of the join point has no free variables and is
trivial, the same argument does not apply, and there's nothing to gain
from preserving it.
On the contrary, not inlining these trivial join points such as
$j f x = K f x |> co
can be actively harmful as they prevent useful optimisations from firing
on the known constructor application. #25723 is such an example.
Therefore, we've extended `uncondInlineJoin` to allow duplicating such closed
trivial join points. See the updated Note [Duplicating join points] for
further details.
Additionally, merge the guards in uncondInlineJoin for point DJ3(b) anad DJ3(c) of
Note [Duplicating join points] to avoid an unnecessary traversal in the
call to `collectArgs`; it's also more uniform.
Co-authored-by: Simon Peyton Jones <simon.peytonjones@gmail.com>
Fixes #25723
-
78de1a55
by M Farkas-Dyck at 2025-02-18T08:54:31-05:00
Scrub some partiality in `GHC.Tc.Gen.Match`.
In particular, we construct a list of the same length as another list, then loop over both and panic if their lengths are unequal. We can avoid this.
-
1dfe9325
by M Farkas-Dyck at 2025-02-18T08:54:31-05:00
Make list of `ParStmtBlock` in `ParStmt` `NonEmpty`.
In the ParStmt constructor Language.Haskell.Syntax.Expr.StmtLR, the 2nd argument, the list of ParStmtBlocks, must be NonEmpty; make it so.
-
0e3575b5
by M Farkas-Dyck at 2025-02-18T08:54:31-05:00
GHC.Tc.Gen.Match: Added type signatures for `loop` functions.
-
c9ffcfee
by sternenseemann at 2025-02-18T08:55:14-05:00
GHC: fix reference to function in Note [Target code interpreter]
As far as I could tell, setSessionDynFlags doesn't deal with hsc_interp.
Also added a backreference so this will be updated in the future.
-
ab77fc8c
by sheaf at 2025-02-18T08:55:57-05:00
Account for skolem escape in mightEqualLater
This commit:
1. Refactors checkTyEqRhs to allow it be called in pure contexts,
which means it skips doing any on-the-fly promotion.
2. Calls checkTyEqRhs in mightEqualLater to check whether it a
MetaTv can unify with a RHS or whether that would cause e.g.
skolem escape errors or concreteness errors.
Fixes #25744
-
cb8a06a4
by Sylvain Henry at 2025-02-18T08:56:52-05:00
Remove a bunch of Makefiles from old build system
-
e12d6b39
by M Farkas-Dyck at 2025-02-18T08:57:37-05:00
Totalize `GHC.HsToCore.Match.matchWrappers.initNablasGRHSs`.
Converting from `NonEmpty` to `[]` and back is totally needless.
-
cd2be3be
by Matthew Pickering at 2025-02-18T08:58:14-05:00
interpreter: Always print uniques for BCO_NAME labels
In the previous commit I omitted to include the unique, which still
makes it very difficult to trace back where the BCO came from.
-
c4e112fc
by Matthew Pickering at 2025-02-18T08:58:51-05:00
interpreter: Fix overflows and reentrancy in statistics calculation
1. Use unsigned long for counter, as they can easily overflow if you are
running a long benchmark.
2. Make interp_shutdown reentrant by copying the command frequency table
into an array.
Fixes #25756
-
70ac6222
by M Farkas-Dyck at 2025-02-18T14:22:06-08:00
Use `Foldable1` where appropriate, avoiding much needless panicking.
In some cases, where not readily feasible to modify code to use `NonEmpty`, merely use `expectNonEmpty` to make explicit we are panicking if we have an empty list.
-
a3f0a506
by Sylvain Henry at 2025-02-19T05:27:30-05:00
Testsuite: fix deprecation warning
> DeprecationWarning: 'count' is passed as positional argument
-
ef5470a2
by Ben Gamari at 2025-02-19T16:30:53+00:00
Cmm/Parser: Add surface syntax for Mul2 MachOps
These are otherwise very hard to test in isolation.
-
59b9307b
by Cheng Shao at 2025-02-19T20:24:40-05:00
testsuite: fix InternalCounters test with +debug_ghc
The `InternalCounters` test case fails when ghc is built with
`+debug_ghc`. This patch skips it in that case and allows the
testsuite to pass for the `+debug_ghc` flavour transformer.
-
aa69187d
by M Farkas-Dyck at 2025-02-19T20:25:31-05:00
Scrub a use of `head` in `GHC.Driver.Make.downsweep_imports.checkDuplicates`.
-
1c8e608a
by Cheng Shao at 2025-02-21T20:18:41-05:00
compiler: use fromAscList when applicable
This patch uses fromAscList (with O(n) complexity) instead of fromList
(with O(nlogn) complexity) in certain Binary instances. It's safe to
do so since the corresponding serialization logic is based on toList
(same as toAscList).
-
549e0aff
by Ben Gamari at 2025-02-21T20:19:18-05:00
rts/linker/MachO: Mark internal symbols as static
There is no reason why these should have external linkage.
-
fbf3d020
by Cheng Shao at 2025-02-22T07:41:01-05:00
wasm: bump dyld v8 heap size limit
This patch sets `--max-old-space-size=65536` as wasm dyld shebang
arguments to lessen v8 heap pressure in certain workloads that load
the full ghc package. It doesn't really commit 64G memory but it does
help reduce v8 gc overhead.
-
cb60da24
by Cheng Shao at 2025-02-22T07:41:01-05:00
wasm: fix dyld for shared libraries created by llvm 20.x
This patch fixes wasm dyld script for shared libraries created by llvm
20.x. The __wasm_apply_data_relocs function is now optional and may be
omitted for shared libraries without any runtime relocatable data
segments, so only call __wasm_apply_data_relocs when it's present.
-
7eea38c8
by Cheng Shao at 2025-02-22T07:41:37-05:00
driver: fix wasm backend sysroot lookup logic when -flto is passed
For the wasm target, the driver calls `wasm32-wasi-clang
--print-search-dirs` and finds the sysroot directory that contains
libc.so etc, then passes the directory path to dyld. However, when GHC
is configured with -flto as a part of C/C++ compiler flags, the clang
driver would insert a llvm-lto specific directory in the
--print-search-dirs output and the driver didn't take that into
account. This patch fixes it and always selects the non-lto sysroot
directory to be passed to dyld. This is one small step towards
supporting building all cbits with lto for wasm.
-
f3bfe31e
by Cheng Shao at 2025-02-23T14:06:25-05:00
wasm: add Note [Variable passing in JSFFI] as !13583 follow up
This patch adds a note to explain how the magic variables like
`__ghc_wasm_jsffi_dyld` are brought into scope of JSFFI code snippets,
as follow up work of !13583.
-
c318be56
by Cheng Shao at 2025-02-23T14:07:02-05:00
libffi: update to 3.4.7
Bumps libffi submodule.
-
33aca30f
by sheaf at 2025-02-25T08:58:46-05:00
LLVM: account for register type in funPrologue
We were not properly accounting for the live register type of
global registers in GHC.CmmToLlvm.CodeGen.funPrologue. This meant that
we could allocated a register at type <4 x i32> but try to write to it
at type <8 x i16>, which LLVM doesn't much like.
This patch fixes that by inserting intermerdiate casts when necessary.
Fixes #25730
-
0eb58b0e
by sheaf at 2025-02-25T08:59:29-05:00
base: make Data.List.NonEmpty.unzip match Data.List
This commit makes Data.List.NonEmpty.unzip match the implementation
of Data.List, as was suggested in approved CLC proposal #107.
-
f4da90f1
by Matthew Pickering at 2025-02-25T14:11:21-05:00
interpreter: Fix underflow frame lookups
BCOs can be nested, resulting in nested BCO stack frames where the inner most
stack frame can refer to variables stored on earlier stack frames via the
PUSH_L instruction.
|---------|
| BCO_1 | -<-┐
|---------|
......... |
|---------| | PUSH_L <n>
| BCO_N | ->-┘
|---------|
Here BCO_N is syntactically nested within the code for BCO_1 and will result
in code that references the prior stack frame of BCO_1 for some of it's local
variables. If a stack overflow happens between the creation of the stack frame
for BCO_1 and BCO_N the RTS might move BCO_N to a new stack chunk while leaving
BCO_1 in place, invalidating a simple offset based reference to the outer stack
frames.
Therefore `ReadSpW` first performs a bounds check to ensure that accesses onto
the stack will succeed. If the target address would not be a valid location for
the current stack chunk then `slow_spw` function is called, which dereferences
the underflow frame to adjust the offset before performing the lookup.
┌->--x | CHK_1 |
| CHK_2 | | | |---------|
|---------| | └-> | BCO_1 |
| UD_FLOW | -- x |---------|
|---------| |
| ...... | |
|---------| | PUSH_L <n>
| BCO_ N | ->-┘
|---------|
Fixes #25750
-
c3f2d284
by Vladislav Zavialov at 2025-02-25T14:11:58-05:00
Remove ArgPatBuilder
ArgPatBuilder in Parser/PostProcess.hs became redundant with the
introduction of InvisPat (36a75b80eb).
This small refactoring removes it.
-
0f2241e9
by sheaf at 2025-02-25T19:23:21-05:00
Propagate long distance info to guarded let binds
This commit ensures that we propagate the enclosing long distance
information to let bindings inside guards, in order to get accurate
pattern-match checking warnings, in particular incomplete record
selector warnings.
Example:
data D = K0 | K1 { fld :: Int }
f :: D -> Int
f d@(K1 {})
| let i = fld d
= i
f _ = 3
We now correctly recognise that the field selector 'fld' cannot fail,
due to the outer pattern match which guarantees that the value 'd' has
the field 'fld'.
Fixes #25749
-
64b0d4d0
by Fangyi Zhou at 2025-02-25T19:24:07-05:00
wasm: use primitive opcodes for fabs and sqrt
- Add new `WasmInstr` constructor `WasmSqrt` for sqrt, corresponding to
primitivie operations in wasm.
- When lowering CallishMachOp, use `WasmAbs` and `WasmSqrt` for F32 and
F64 fabs and sqrt.
-
272eaef0
by Cheng Shao at 2025-02-25T19:24:43-05:00
hadrian: enable building stage1 haddock for cross ghc
This commit enables building stage1 haddock for cross ghc. Without
this change, hadrian would panic with "Unknown program" error when
building the _build/stage1/bin/cross-prefix-haddock program needed by
the docs-haddock target, even if it only needs to copy from
_build/stage0/bin/cross-prefix-haddock.
-
a794e733
by Cheng Shao at 2025-02-25T19:24:43-05:00
hadrian: enable building docs for cross targets
Hadrian used to omit the docs target as a part of binary-dist-dir for
cross targets. This commit enables docs to be built as a part of cross
bindists and it works just fine in CI.
-
6dba56e1
by Cheng Shao at 2025-02-25T19:24:43-05:00
ci: build haddock/sphinx-html for wasm jobs
This commit enables building haddock & sphinx-html documentation for
wasm targets. The docs are useful for end users and should be tested
in CI.
I've omitted pdf & manpage generation for the wasm target; I've never
found the pdf version of docs to be useful, and the manpage only
contains `ghc.1` where we really want `wasm32-wasi-ghc.1` but that
should be a separate issue to fix.
-
2d6a63ab
by Cheng Shao at 2025-02-25T19:25:20-05:00
ghci: remove unused showBreakArray function
GHCi.BreakArray.showBreakArray is not used anywhere, hence the
housecleaning.
-
b228fcb5
by Cheng Shao at 2025-02-25T19:25:57-05:00
ghc-heap: fix HalfWord incompatible Binary instances for cross GHC
ghc-heap defines HalfWord as Word32/Word16 depending on host word
size. For cross GHC with different host/target word sizes, the Binary
instances are incompatible and breaks iserv serialization of any
message type that involves HalfWord, breaking the ghci debugger. This
patch fixes the issue and has been tested to fix ghci debugger
functionality of the wasm backend. Fixes #25420 #25781.
-
ec02f8c2
by Rodrigo Mesquita at 2025-02-26T11:03:38-05:00
ghci-debugger: display thunks provenance if avail
Improves reporting on ghci breakpoints when IPE information is available
by printing, next to the thunk, the source file and src span where the
thunk originated.
Closes #25746
-
6acaff2b
by Vladislav Zavialov at 2025-02-26T11:04:15-05:00
Tidy up error messages for TypeAbstractions
1. Print the '@' symbol before invisible patterns and improve phrasing:
T24557c.hs:8:4: error: [GHC-11983]
- Invisible type pattern pat is not allowed here
+ Illegal invisible type pattern: @pat
+ An invisible type pattern must occur in an argument position.
2. Use a single error code for all type abstractions deemed illegal
due to the TypeAbstractions extension being disabled.
Before this change:
* [GHC-78249] was used in function equations, lambdas
* [GHC-17916] was used in constructor patterns
After this change:
* [GHC-78249] is used to report all illegal type abstractions
* [GHC-17916] is no longer used
There was no reason for both error codes to exist and this distinction
was a source of complexity in GHC/Tc/Errors/* and GHC/Rename/Pat.hs
3. Group the different "invisible type pattern" error constructors
under a single parent constructor, TcRnIllegalInvisibleTypePattern
containing BadInvisPatReason
-
1ce9502e
by Ben Gamari at 2025-02-27T04:48:29-05:00
haddock/doc: Drop version and release
We currently have no way of keeping this up-to-date with the project version
-
7f358f25
by Matthew Pickering at 2025-02-27T04:49:06-05:00
testsuite: Add test for :steplocal performance
This adds a simple test which exercises #25779
-
a6a3ffa6
by Sven Tennie at 2025-02-27T23:34:47-05:00
Do not deallocate stack for jump/switch table jumps
Though the name is misleading, we consider them to be branching. For
branch instructions we do not deallocate (parts of) the stack, but keep
the stack pointer (sp) intact.
-
39e51ddb
by Sven Tennie at 2025-02-27T23:34:47-05:00
Add reproducer for dealloc instructions in switch table jump expressions (#25733)
Measures taken to make the test stable:
- Use 'a' as variable prefix, because X86 32bit stumbled over the
variable name 'i386'
- Flush stdout to make test output deterministic
- Use type annotations to support 32bit archs
-
d427df93
by Sylvain Henry at 2025-02-27T23:35:30-05:00
Remove redundant location strings in expectJust and friends (#25743)
Now we can use HasDebugCallStack instead to avoid cluttering the code
with strings and to avoid maintaining those strings (e.g. renaming them
when functions are renamed...).
-
90f1190e
by Ben Gamari at 2025-02-28T20:53:53-05:00
compiler: Add export list to GHC.SysTools.Tasks
-
ec826009
by Ben Gamari at 2025-02-28T20:53:53-05:00
compiler: Pass --target to llvm-as
As noted in #25793, this is necessary due to potential ambiguity on
Apple machines with Rosetta.
-
9c1647d1
by Andreas Klebinger at 2025-02-28T20:54:30-05:00
cmmMachOpFoldM: Add missing pattern matches for bitcasts.
Fixes #25771
-
3b78e139
by John Ericson at 2025-03-03T15:27:39-05:00
Remove most of `GHC.Internal.Pack`
Since bd82ac9f4716e28b185758ae514691d5a50c003f when `GHC.Pack` was
deleted, it is no longer used except for one function by the RTS.
-
b4fe0850
by Rodrigo Mesquita at 2025-03-03T15:28:16-05:00
ghci: Don't set virtualCWD on every iteration
The calls to withVirtualCWD were introduced to fix #2973, but this bug
is no longer reproducible, even when `withVirtualCWD` is dropped.
This cleanup was originally motivated by the performance of :steplocal,
but the performance problem has now been fixed at its root in the next
commit.
Even then, `withVirtualCWD` seems to now be an unnecessary artifact, and
removing it simplifies the interpreter with no apparent drawbacks (testsuite is
also happy with this change)
-
73ba1e6e
by Rodrigo Mesquita at 2025-03-03T15:28:16-05:00
ghci debugger: improve break/resume control flow
After interpreting bytecode (`evalStmt`), we may want to hand off
control to "GHCi.UI" in order to display an interactive break prompt:
1. When an /active/ breakpoint (one set with :break ...) is hit
2. At any breakpoint, when using :step from a breakpoint
3. At any breakpoint in the same function f, when :steplocal is called
from a breakpoint in f
4. At any breakpoint in the same module, when :stepmodule is used
Whether to pass control to the UI is now fully determined by
`handleRunStatus` which transforms an `EvalStatus_` into an
`ExecResult`. When `ExecBreak` is returned from `handleRunStatus` to
GHCi, it always means GHCi breaks.
`handleRunStatus` determines whether to loop and resume evaluation right away, or
when to return to GHCi (by returning `ExecBreak` or `ExecComplete`).
- (1) is queried using the `BreakpointStatus` message (the
`breakpointStatus` call)
- (2,3,4) are determined by the predicate `breakHere step span`, which
inspects the improved `SingleStep` type to determine whether we care
about this breakpoint even if it is not active.
This refactor solves two big performance problems with the previous control flow:
- We no longer call `withArgs/withProgram` repeatedly in the
break/resume loop, but rather just once "at the top".
- We now avoid computing the expensive `bindLocalsAtBreakpoint` for
breakpoints we'd never inspect.
In the interpreter_steplocal test added, calling `:steplocal` after breaking on `main = fib 25`
now takes 12 seconds rather than 49 seconds on my machine.
```
interpreter_steplocal(ghci) ghc/alloc 6,124,821,176 540,181,392 -91.2% GOOD
```
Fixes #25779
-------------------------
Metric Decrease:
interpreter_steplocal
-------------------------
-
c78d8f55
by Cheng Shao at 2025-03-03T20:54:41+00:00
rts: fix top handler closure type signatures
This commit fixes the runIO/runNonIO closure type signatures in the
RTS which should be extern StgClosure. This allows us to remove an
unnecessary type cast in the C foreign desugaring logic, as well as
unneeded complications of JSFFI desugaring logic that also needs to
generate C stubs that may refer to those top handler closures.
Otherwise, we'll have to take special care to avoid generating "extern
StgClosure" declarations for them as we would for other closures, just
to avoid conflicting type signature error at stub compile time.
-
a204df3a
by Cheng Shao at 2025-03-03T20:54:41+00:00
compiler: allow arbitrary label string for JSFFI exports
This commit allows arbitrary label string to appear in a foreign
export declaration, as long as the calling convention is javascript.
Well, doesn't make sense to enforce it's a C function symbol for a
JSFFI declaration anyway, and it gets in the way of implementing the
"sync" flavour of exports.
-
03ebab52
by Cheng Shao at 2025-03-03T20:54:41+00:00
compiler: wasm backend JSFFI sync exports
This commit implements the synchronous flavour of the wasm backend
JSFFI exports:
- `foreign export javascript "foo sync"` exports a top-level Haskell
binding as a synchronous JS function
- `foreign import javascript "wrapper sync"` dynamically exports a
Haskell function closure as a synchronous JS function
- `foreign import javascript unsafe` is now re-entrant by lowering to
a safe ccall
- Also fix the issue that JSFFI dynamic exports didn't really work in
TH & ghci (#25473)
-
b6ae908b
by Cheng Shao at 2025-03-03T20:54:41+00:00
testsuite: test wasm backend JSFFI sync exports
This commit repurposes some existing JSFFI test cases to make them
cover JSFFI sync exports as well.
-
edae2874
by Cheng Shao at 2025-03-03T20:54:41+00:00
docs: document wasm backend JSFFI sync exports
This commit updates wasm backend documentation to reflect the new
JSFFI sync exports feature.
-
9b54eecb
by Cheng Shao at 2025-03-03T20:56:21+00:00
wasm: add error message to WouldBlockException
This commit attaches an error message to WouldBlockException, for now
the error message consists of the JS async import code snippet that
thunk is trying to block for. This is useful for debugging synchronous
callbacks that accidentally call an async JS function.
-
c331eebf
by Cheng Shao at 2025-03-04T09:11:45-05:00
compiler: avoid overwriting existing writers in putWithTables
This patch makes `putWithTables` avoid overwriting all existing
UserData writers in the handle. This is crucial for GHC API users that
use putWithUserData/getWithUserData for serialization logic that
involve Names.
-
e9b7802b
by Matthew Pickering at 2025-03-04T09:12:21-05:00
ghci: Serialise mi_top_env
When loading core from interface files (or from a bytecode object in
future) it's important to store what the top-level context of a module
is.
Otherwise, when you load the module into GHCi from the interface files,
only exported identifiers from the top-level module are in scope on the
repl.
See the added test which demonstrates what this enables.
The context at the GHCi prompt is everything that's in-scope in the
TopEnvIface module. Since TopEnvIface imports identifier "a", we can
evaluate "a" in the repl.
In addition to all this, we can use this information in order to
implement reifyModule in a more principled manner.
This becomes even more important when you're debugging and what to set
break-points on functions which are not imported.
-
73e02068
by Matthew Pickering at 2025-03-04T09:12:21-05:00
Implement reifyModule in terms of mi_top_env
mi_top_env provides precisely the information that reifyModule needs,
the user written imports.
This is important as it unblocks !9604 and #22188
Fixes #8489
-
0a99825d
by Ben Gamari at 2025-03-04T09:12:57-05:00
hadrian: Refactor handling of test suite environment
Previously we would set the environment variables used to run the
testsuite driver using `setEnv` to set them in the Hadrian process.
While looking into failures of a fix to #25752 I noticed this and took
the opportunity to refactor.
-
7ca72844
by Alan Zimmerman at 2025-03-04T09:13:34-05:00
[EPA] Sync with the ghc-exactprint repo
This brings it into line with the changes in
https://hackage.haskell.org/package/ghc-exactprint-1.12.0.0
But also keeps the latest changes from master.
-
8f6cc90c
by Matthew Pickering at 2025-03-05T04:48:02-05:00
perf: Speed up the bytecode assembler
This commit contains a number of optimisations to the bytecode
assembler. In programs which generate a large amount of bytecode, the
assembler is called a lot of times on many instructions.
1. Specialise the assembleI function for the two intepreters to avoid
having to materialise the intermediate free-monad like structure.
2. Directly compute the UArray and SmallArray needed rather than going
via the intermediate SizedSeq
3. Use optimised monads
4. Define unrolled "any" and "mapM6" functions which can be inlined
and avoid calling recursive functions.
The resulting generated code is much more direct.
Before:
./ByteCodeAsm /home/matt/ghc-profiling-light/_build/stage1/lib/ +RTS -s
48,923,125,664 bytes allocated in the heap
678,221,152 bytes copied during GC
395,648 bytes maximum residency (2 sample(s))
50,040 bytes maximum slop
6 MiB total memory in use (0 MiB lost due to fragmentation)
Tot time (elapsed) Avg pause Max pause
Gen 0 11731 colls, 0 par 0.419s 0.425s 0.0000s 0.0004s
Gen 1 2 colls, 0 par 0.001s 0.001s 0.0007s 0.0012s
INIT time 0.000s ( 0.000s elapsed)
MUT time 6.466s ( 6.484s elapsed)
GC time 0.421s ( 0.426s elapsed)
EXIT time 0.000s ( 0.000s elapsed)
Total time 6.887s ( 6.910s elapsed)
After:
1,518,321,200 bytes allocated in the heap
4,299,552 bytes copied during GC
322,288 bytes maximum residency (2 sample(s))
50,280 bytes maximum slop
6 MiB total memory in use (0 MiB lost due to fragmentation)
Tot time (elapsed) Avg pause Max pause
Gen 0 369 colls, 0 par 0.003s 0.003s 0.0000s 0.0002s
Gen 1 2 colls, 0 par 0.001s 0.001s 0.0007s 0.0012s
INIT time 0.001s ( 0.001s elapsed)
MUT time 0.465s ( 0.466s elapsed)
GC time 0.004s ( 0.004s elapsed)
EXIT time 0.000s ( 0.000s elapsed)
Total time 0.470s ( 0.471s elapsed)
-
f2d43e11
by Teo Camarasu at 2025-03-05T04:48:40-05:00
ghc-boot-th: expose all TH packages from proper GHC.Boot.* modules
Previously we defined some modules here in the GHC.Internal namespace.
Others were merely re-exposed from GHC.Internal.
Re-exposed modules weren't handled correctly by Haddock, so the
Haddocks for the `template-haskell` library couldn't see them.
This change also makes the home package of these modules a bit clearer.
Work towards #25705
-
91ef82df
by Teo Camarasu at 2025-03-05T04:48:40-05:00
ghc-boot-th: fix synopsis formatting
`@...@` syntax doesn't seem to work in synposes and is just kept by
Haddock verbatim.
-
eb9fe1ec
by Brandon Chinn at 2025-03-05T04:49:17-05:00
Collapse string gaps as \& (#25784)
In 9.10, "\65\ \0" would result in "A0", but in 9.12, it results in
"\650", due to the string refactoring I did in !13128. Previously, we
were resolving escape codes and collapsing string gaps as we come across
them, but after the refactor, string processing is broken out into
phases, which is both more readable and useful for multiline strings.
-
8037f487
by Cheng Shao at 2025-03-05T04:49:54-05:00
ghc-experimental: make JSVal abstract in GHC.Wasm.Prim
This commit makes JSVal an abstract type in the export list of
GHC.Wasm.Prim. JSVal's internal representation is supposed to be a non
user facing implementation detail subject to change at any time. We
should only expose things that are newtypes of JSVal, not JSVal
itself.
-
4f342431
by Cheng Shao at 2025-03-05T04:49:54-05:00
wasm: make JSVal internal Weak# point to lifted JSVal
JSVal has an internal Weak# with the unlifted JSVal# object as key to
arrange its builtin finalization logic. The Weak# used to designate
Unit_closure as a dummy value; now this commit designates the lifted
JSVal closure as the Weak# value. This allows the implementation of
mkWeakJSVal which can be used to observe the liveliness of a JSVal and
attach a user-specified finalizer.
-
55af20e6
by Cheng Shao at 2025-03-05T04:49:54-05:00
ghc-experimental: add mkWeakJSVal
This commit adds a mkWeakJSVal function that can be used to set up a
Weak pointer with a JSVal key to observe the key's lifetime and
optionally attach a finalizer.
-
8273d7d1
by Matthew Pickering at 2025-03-05T04:50:30-05:00
simplifier: Zap Id unfoldings before constructing InScopeSet in simpleOptExpr
Care must be taken to remove unfoldings from `Var`s collected by exprFreeVars
before using them to construct an in-scope set hence `zapIdUnfolding` in `init_subst`.
Consider calling `simpleOptExpr` on an expression like
```
case x of (a,b) -> (x,a)
```
* One of those two occurrences of x has an unfolding (the one in (x,a), with
unfolding x = (a,b)) and the other does not. (Inside a case GHC adds
unfolding-info to the scrutinee's Id.)
* But exprFreeVars just builds a set, so it's a bit random which occurrence is collected.
* Then simpleOptExpr replaces each occurrence of x with the one in the in-scope set.
* Bad bad bad: then the x in case x of ... may be replaced with a version that has an unfolding.
Fixes #25790
-
07fe6d1d
by Rodrigo Mesquita at 2025-03-05T04:51:07-05:00
docs: Fix ghci :doc documentation
Fixes #25799
-
a510b861
by Matthew Pickering at 2025-03-06T11:43:23+00:00
Add flag to control whether self-recompilation information is written to interface
This patch adds the flag -fwrite-if-self-recomp which controls whether
interface files contain the information necessary to answer the
question:
Do I need to recompile myself or is this current interface file
suitable?
Why? Most packages are only built once either by a distribution or cabal
and then placed into an immutable store, after which we will never ask
this question. Therefore we can derive two benefits from omitting this
information.
* Primary motivation: It vastly reduces the surface area for creating
non-deterministic interface files. See issue #10424 which motivated a
proper fix to that issue. Distributions have long contained versions
of GHC which just have broken self-recompilation checking (in order to
get deterministic interface files).
* Secondary motivation: This reduces the size of interface files
slightly.. the `mi_usages` field can be quite big but probably this
isn't such a great benefit.
* Third motivation: Conceptually clarity about which parts of an
interface file are used in order to **communicate** with subsequent
packages about the **interface** for a module. And which parts are
used to self-communicate during recompilation checking.
The main tracking issue is #22188 but fixes issues such as #10424 in a
proper way.
-
5b05c27b
by Matthew Pickering at 2025-03-06T11:43:23+00:00
Disable self recomp in release flavour
The interface files that we distribute should not contain any
information which is used by the recompilation checking logic since
source file will never be compiled again.
I am not 100% sure this won't cause unexpected issues, there many be
downstream consumers which are incorrectly using the information from
interfaces, but this commit can be reverted if we detect issues.
-
1d4c9824
by Matthew Craven at 2025-03-06T18:11:59-05:00
Cmm: Add surface syntax for Word/Float bitcast ops
-
25c4a2a2
by Matthew Craven at 2025-03-06T18:11:59-05:00
Cmm: Add constant-folding for Word->Float bitcasts
-
30bdea67
by Matthew Craven at 2025-03-06T18:11:59-05:00
Add tests for #25771
-
44bf5fa1
by Matthew Pickering at 2025-03-07T13:48:18+00:00
iface: Store flags in interface files
When reporting the reason why a module is recompiled (using
`-dump-hi-diffs`), it is much more informative to inform the user about
which flag exactly has changed, rather than just an opaque reference to
a hash.
Now, when the user enables `-fwrite-if-self-recomp-flags`
there is a difference the precise part of the flags is
reported:
```
codegen flags changed:
before: [Opt_NoTypeableBinds, Opt_OmitYields]
after: [Opt_NoTypeableBinds, Opt_OmitYields, Opt_DictsStrict]
```
Fixes #25571
-
324222bd
by Oleg Grenrus at 2025-03-08T08:50:18-05:00
Run fix-whitespace on compiler/
https://hackage.haskell.org/package/fix-whitespace
IMO this should be included into lint suite
-
1e53277a
by sheaf at 2025-03-08T16:32:25-05:00
Allow defaulting of representational equalities
This commit generalises the defaulting of equality constraints that
was introduced in 663daf8d (with follow-up in 6863503c) to allow
the defaulting of *representational* equality constraints.
Now we default a representational equality
ty1 ~R# ty2
by unifying ty1 ~# ty2.
This allows the following defaulting to take place:
- Coercible alpha[tau] Int ==> alpha := Int
- Coercible (IO beta[tau]) (IO Char) ==> beta := Char
See Note [Defaulting representational equalities] in GHC.Tc.Solver.Default
for more details.
Fixes #21003
-
d6c40afc
by Andreas Klebinger at 2025-03-08T16:33:02-05:00
Revert "Use `Infinite` in unique generation, and clean up some other partial uni patterns as well."
This reverts commit 643dd3d86968c527ba07ece9cc337728dbdfe2a0.
As described in #25817 this commit introduced a subtle bug in AArch64
code generation. So for the time being I will simply revert it
wholesale.
-
68310e11
by Andreas Klebinger at 2025-03-08T16:33:39-05:00
Properly describe acceptance window for stat tests.
The relative metric is already in %, so no need to multiply by 100.
-
cca68421
by Cheng Shao at 2025-03-08T22:04:42-05:00
wasm: do not use wasm type reflection in dyld
The wasm dynamic linker used to depend on v8's experimental wasm type
reflection support to generate stub functions when treating GOT.func
items that aren't exported by any loaded library yet. However, as we
work towards wasm ghci browser mode (#25399), we need to ensure the
wasm dyld logic is portable across browsers. So this commit removes
the usage of wasm type reflection in wasm dyld, and it shall only be
added many months later when this feature is widely available in
browsers.
-
75fcc5c9
by Cheng Shao at 2025-03-08T22:05:19-05:00
wasm: don't create a wasm global for dyld poison
There's a much more efficient way to convert an unsigned i32 to a
signed one. Thanks, o3-mini-high.
-
fd40eaa1
by Cheng Shao at 2025-03-08T22:05:19-05:00
wasm: revamp JSFFI internal implementation and documentation
This patch revamps the wasm backend's JSFFI internal implementation
and documentation:
- `JSValManager` logic to allocate a key is simplified to simple
bumping. According to experiments with all major browsers, the
internal `Map` would overflow the heap much earlier before we really
exhaust the 32-bit key space, so there's no point in the extra
complexity.
- `freeJSVal` is now idempotent and safe to call more than once. This
is achieved by attaching the `StablePtr#` to the `JSVal#` closure
and nullifying it when calling `freeJSVal`, so the same stable
pointer cannot be double freed.
- `mkWeakJSVal` no longer exposes the internal `Weak#` pointer and
always creates a new `Weak#` on the fly. Otherwise by finalizing
that `Weak#`, user could accidentally drop the `JSVal`, but
`mkWeakJSVal` is only supposed to create a `Weak` that observes the
`JSVal`'s liveliness without actually interfering it.
- `PromisePendingException` is no longer exported since it's never
meant to be caught by user code; it's a severe bug if it's actually
raised at runtime.
- Everything exported by user-facing `GHC.Wasm.Prim` now has proper
haddock documentation.
- Note [JSVal representation for wasm] has been updated to reflect the
new JSVal# memory layout.
-
cbae3708
by Ben Gamari at 2025-03-11T06:09:58-04:00
users guide: Fix typo
-
1951eb7a
by Ben Gamari at 2025-03-11T06:10:35-04:00
testsuite: Don't count fragile passes as failures in JUnit output
As noted in #25806, the testsuite driver's JUnit output
previously considered passes of fragile tests to be failures. Fix this.
Closes #25806.
-
589f40b9
by Matthew Pickering at 2025-03-11T06:11:11-04:00
Use panic rather than error in expectJust
Otherwise, we would not get a callstack printed out when the exception
occurs.
Fixes #25829
-
d450e88e
by sheaf at 2025-03-11T06:42:59-04:00
Solve Wanted quantified constraints from Givens
This commit ensures we directly solve Wanted quantified constraints from
matching inert Given quantified constraints,instead of going through the
trouble of emitting an implication constraint and processing that.
This is not just an optimisation; it makes our lives easier when
generating RULEs for specialisation.
See Note [Solving Wanted QCs from Given QCs] for details
Fixes #25758
-
48daaf53
by Ben Gamari at 2025-03-11T06:42:59-04:00
testsuite: Add testcase for #25577
-
d2ffb0ce
by Ben Gamari at 2025-03-11T06:42:59-04:00
testsuite/ghc-api: Eliminate Makefile usage from various GHC API tests
These tests can be expressed perfectly well using the testsuite driver
itself.
-
2275b642
by Ben Gamari at 2025-03-11T06:42:59-04:00
rts/linker/MachO: Assert that GOT relocations have GOT entries
In #25577 we found that some GOT relocation types were not being given
relocation entries. Add assertions to catch this sort of failure in the
future.
-
8c96bcb4
by Ben Gamari at 2025-03-11T06:42:59-04:00
rts/linker/MachO: Account for internal GOT references in GOT construction
Previously we failed to give GOT slots to symbols which were referred to
by GOT relocations in the same module. This lead to #25577.
Fix this by explicitly traversing relocation lists and maintaining a
`needs_got` flag for each symbol.
Fixes #25577.
-
7b84c588
by Vladislav Zavialov at 2025-03-11T06:43:02-04:00
One list in ConPat (part of #25127)
This patch changes PrefixCon to use one list instead of two:
-data HsConDetails tyarg arg rec
- = PrefixCon [tyarg] [arg]
+data HsConDetails arg rec
+ = PrefixCon [arg]
| RecCon rec
| InfixCon arg arg
The [tyarg] list is now gone. To understand the effect of this change,
recall that there are three instantiations of HsConDetails:
1. type HsConPatDetails p =
HsConDetails (HsConPatTyArg (NoGhcTc p)) -- tyarg
(LPat p) -- arg
(HsRecFields p (LPat p)) -- rec
2. type HsConDeclH98Details pass =
HsConDetails Void -- tyarg
(HsScaled pass (LBangType pass)) -- arg
(XRec pass [LConDeclField pass]) -- rec
3. type HsPatSynDetails pass =
HsConDetails Void -- tyarg
(LIdP pass) -- arg
[RecordPatSynField pass] -- rec
In cases (2) and (3), tyarg was instantiated to Void, so the [tyarg]
list was always empty. Its removal is basically a no-op.
The interesting case is (1), which is used in ConPat to represent
pattern matching of the form (MkE @tp1 @tp2 p1 p2).
With this patch, its representation is changed as follows:
ConPat "MkE" [tp1, tp2] [p1, p2] -- old
ConPat "MkE" [InvisP tp1, InvisP tp2, p1, p2] -- new
The new mixed-list representation is consintent with lambdas, where
InvisP is already used to deal with \ @tp1 @tp2 p1 p2 -> body.
The immediate effect of the new representation is an improvement to
error messages. Consider the pattern (Con x @t y). Previously it
resulted in a parse error because @t could not occur after x. Now it is
reported as [GHC-14964]. Test case: TyAppPat_MisplacedApplication.
In the long term, this is intended as preparation for #18389 and #25127,
which would make (Con x @t y) potentially valid, e.g. if its type is
Con :: forall a -> forall b. (a, b) -> T
The TH AST is left unchanged for the moment to avoid breakage.
-
cce869ea
by Vladislav Zavialov at 2025-03-11T06:43:02-04:00
Error message with EmptyCase and RequiredTypeArguments (#25004)
Fix a panic triggered by a combination of \case{} and forall t ->
ghci> let f :: forall (xs :: Type) -> (); f = \case {}
panic! (the 'impossible' happened)
GHC version 9.10.1:
Util: only
The new error message looks like this:
ghci> let f :: forall (xs :: Type) -> (); f = \case {}
<interactive>:5:41: error: [GHC-48010]
• Empty list of alternatives in \case expression
checked against a forall-type: forall xs -> ...
This is achieved as follows:
* A new data type, BadEmptyCaseReason, is now used to describe
why an empty case has been rejected. Used in TcRnEmptyCase.
* HsMatchContextRn is passed to tcMatches, so that the type checker
can attach the syntactic context to the error message.
* tcMatches now rejects type arguments if the list of alternatives is
empty. This is what fixes the bug.
-
37d8b50b
by sheaf at 2025-03-11T06:43:06-04:00
user's guide: consolidate defaulting documentation
This commit adds a new section on defaulting, which consolidates various
parts of documentation surrounding defaulting into one central place.
It explains type class defaulting in detail, extensions to it with
OverloadedStrings, NamedDefaults and ExtendedDefaultRules, as well
as other defaulting mechanisms (e.g. kind-based defaulting such as
RuntimeRep defaulting, and defaulting of equalities).
-
0c9fd8d4
by sheaf at 2025-03-11T06:43:06-04:00
user's guide: flesh out XOverloadedStrings docs
This commit extends the documentation of the OverloadedStrings extension
with some usage information, in particular suggestions to:
- use default declarations, such as `default (Text)` or
`default IsString(Text)` (with the NamedDefaults extension),
- enable the ExtendedDefaultRules extension to relax the requirement
that a defaultable type variable must only appear in unary standard
classes
Fixes #23388
-
2df171d4
by sheaf at 2025-03-11T06:43:06-04:00
user's guide: NamedDefaults vs ExtendedDefaultRules
This commit clarifies the defaulting rules with NamedDefaults,
in particular in situations where a type variable appears in other
constraints than standard/unary constraints.
-
77df05d0
by Matthew Pickering at 2025-03-11T06:43:07-04:00
Take into account all flags when computing iface_hash
The "interface hash" should contain a hash of everything in the
interface file. We are not doing that yet but at least a start is to
include a hash of everything in `mi_self_recomp`, rather than just
`mi_src_hash` and `mi_usages`.
In particular, this fixes #25837, a bug where we should recompile a
`dyn_hi` file but fail to do so.
-
48b8f110
by Matthew Pickering at 2025-03-11T06:43:07-04:00
Pass -fPIC to dynamicToo001 test to avoid platform dependence issues
On darwin platforms, `-fPIC` is always enabled but on linux it is only
enabled in the dynamic flavour. This can cause a difference in
interface files (see #25836).
The purpose of this test isn't to test module A recompilation, so we
avoid this platform dependency by always passing `-fPIC`.
-
03c72f01
by Matthew Pickering at 2025-03-11T06:43:07-04:00
Remove mi_used_th field from interface files
In the distant past, recompilation checking was disabled for interfaces which used
TemplateHaskell, but for several years now recompilation checking has
been more fine-grained. This has rendered this field unused and
lingering in an interface file.
-
6bb0e261
by Matthew Pickering at 2025-03-11T06:43:07-04:00
Remove mi_hpc field from interface files
The `mi_hpc` field is not used for anything as far as I can discern so
there is no reason to record in the private interface of a module that
there are modules in the transitive closure which use `hpc`.
You can freely mix modules which use `-fhpc` and ones which don't.
Whether to recompile a module due to `-fhpc` being passed to the module
itself is determined in `fingerprintDynFlags`.
-
b6d5b091
by Simon Peyton Jones at 2025-03-11T22:39:23-04:00
We can't UNPACK multi-constructor GADTs
This MR fixes #25672
See Note [Unpacking GADTs and existentials] in GHC.Types.Id.Make
-
8eae151d
by Teo Camarasu at 2025-03-11T22:40:00-04:00
template-haskell: Add explicit exports lists to all remaining modules
-
db621b58
by Teo Camarasu at 2025-03-11T22:40:00-04:00
template-haskell: fix haddocks
It seems that we need a direct dependency on ghc-internal, otherwise
Haddock cannot find our haddocks
The bug seems to be caused by Hadrian because if I rebuild with
cabal-install (without this extra dependency) then I get accurate
Haddocks.
Resolves #25705
-
64ea68d9
by Ben Gamari at 2025-03-12T07:11:51-04:00
mk-ghcup-metadata: Clean up and add type annotations
Getting this file right has historically been quite painful as it is a
dynamically-typed script running only late in the release pipeline.
-
b3f80b07
by Ben Gamari at 2025-03-12T07:12:27-04:00
rts: Drop imports of pthreads functions in cmm sources
These are no longer used. I noticed these while looking for uses of
__PIC__ in Cmm sources.
-
915a6781
by Matthew Pickering at 2025-03-13T01:46:41-04:00
interfaces: Ensure that forceModIface deeply forces a ModIface
A ModIface is the result of compilation that we keep for a long time in
memory. Therefore, it's very important to manage what we are going to
retain and remove any external references to things which we might have
captured compilation.
If storing your ModIface in memory uses too much space, then store
less things or make it use a more efficient representation.
In the past there have been many space leak bugs by not sufficiently
forcing a ModIface (#15111)
This patch adds all the missing NFData instances for all the places I
could find where we weren't deeply forcing the structure.
-
24d373a6
by Matthew Craven at 2025-03-13T01:47:18-04:00
Add interface-stability test for ghc-prim
-
0cb1db92
by sheaf at 2025-03-14T13:11:44-04:00
Don't report used duplicate record fields as unused
This commit fixes the bug reported in #24035 in which the import of a
duplicate record field could be erroneously reported as unused.
The issue is that an import of the form "import M (fld)" can import
several different 'Name's, and we should only report an error if ALL
of those 'Name's are unused, not if ANY are.
Note [Reporting unused imported duplicate record fields]
in GHC.Rename.Names explains the solution to this problem.
Fixes #24035
-
f1830d74
by Matthew Pickering at 2025-03-14T13:12:21-04:00
binary: Directly copy ShortByteString to buffer rather than go via ByteString
This avoids allocating an intermediate bytestring. I just noticed on a
profile that `putFS` was allocating, and it seemed strange to me why
since it should just copy the contents of the FastString into the
already allocated buffer. It turned out we were going indirectly via a
ByteString.
Fixes #25861
-
b15fca2b
by Matthew Pickering at 2025-03-15T05:36:40-04:00
iface: Store logical parts of ModIface together
The ModIface structure is divided into several logical parts:
1. mi_mod_info: Basic module metadata (name, version, etc.)
2. mi_public: The public interface of the module (the ABI), which includes:
- Exports, declarations, fixities, warnings, annotations
- Class and type family instances
- Rewrite rules and COMPLETE pragmas
- Safe Haskell and package trust information
- ABI hashes for recompilation checking
4. mi_self_recomp: Information needed for self-recompilation checking
(see Note [Self recompilation information in interface files])
5. mi_simplified_core: Optional simplified Core for bytecode generation
(only present when -fwrite-if-simplified-core is enabled)
6. mi_docs: Optional documentation (only present when -haddock is enabled)
7. mi_top_env: Information about the top-level environment of the original source
8. mi_ext_fields: Additional fields for extensibility
This structure helps organize the interface data according to its purpose and usage
patterns. Different parts of the compiler use different fields. By separating them
logically in the interface we can arrange to only deserialize the fields that are needed.
This patch also enforces the invariant that the fields of ModIface are
lazy. If you are keeping a ModIface on disk, then force it using
`forceModIface`. Otherwise, when the `ModIface` is read from disk, only
the parts which are needed from the interface will be deserialised.
In a follow-up patch I will tackle follow-up issues:
* Recompilation checking doesn't take into account exported named defaults (#25855)
* Recompilation checking does not take into account COMPLETE pragmas (#25854)
* mi_deps_ field in an interface is confused about whether the
information is for self-recompilation checking or part of the ABI
(#25844)
Fixes #25845
-------------------------
Metric Decrease:
MultiLayerModulesDefsGhciWithCore
-------------------------
-
c758cb71
by Ben Gamari at 2025-03-15T05:37:17-04:00
configure: Fix incorrect SettingsLlvmAsFlags value
Previously this was set to `LlvmAsCmd` rather than `LlvmAsFlags`,
resulting in #25856.
-
cfaaca14
by sheaf at 2025-03-18T20:05:03-04:00
Fix buglet in isEmptyWorkList
There was a missing case in GHC.Tc.Solver.InertSet.isEmptyWorkList; it
mistakenly ignored the 'wl_rw_eqs' field. This commit simply fixes that.
No test case.
-
9f9fe0b3
by sheaf at 2025-03-18T20:05:03-04:00
Add mapMaybeTM method to TrieMap class
This commit adds a new method to the TrieMap class, mapMaybeTM, and
adds implementations to all the instances.
mapMaybeTM is useful when filtering containers that contain other
containers.
-
393531ff
by Simon Peyton Jones at 2025-03-18T20:05:03-04:00
Specialising expressions -- at last
This MR addresses #24359, which implements the GHC proposal 493 on SPECIALISE pragmas.
* The old code path (using SpecSig and SpecPrag) still exists.
* The new code path (using SpecSigE and SpecPragE) runs alongside it.
* All SPECIALISE pragmas are routed through the new code path, except
if you give multiple type sigs, when the old code path is still used.
* Main documentation: Note [Handling new-form SPECIALISE pragmas] in
GHC.Tc.Gen.Sig`
Thanks to @sheaf for helping with this MR.
The Big Thing is to introduce
{-# SPECIALISE forall x. f @Int x True #-}
where you can give type arguments and value argument to specialise; and
you can quantify them with forall, just as in Rules.
I thought it was going to be pretty simple, but it was a Long, Long Saga.
Highlights
* Overview Note [Handling new-form SPECIALISE pragmas] in GHC.Tc.Gen.Sig
- New data constructor `SpecSigE` in data type `L.H.S.Binds.Sig`
- New data construtor `SpecPragE` in data type `GHC.Hs.Binds.TcSpecPrag`
- Renamer: uses `checkSpecESigShape` to decide which function to assocate the
SPECIALISE pragma with
- Some of the action is in `GHC.Tc.Gen.Sig.tcSpecPrag`
- The rest is in `GHC.HsToCore.Binds.dsSpec`
* We use a new TcS mode, TcSFullySolve, when simplifying the Wanteds
that arise from the specialise expression. The mechanism is explained
in Note [TcSFullySolve] in GHC.Tc.Solver.Monad. The reason why we need
to do this is explained in Note [Fully solving constraints for specialisation]
in GHC.Tc.Gen.Sig.
* All of GHC.Tc.Gen.Rule is moved into GHC.Tc.Gen.Sig, because the code is
very closely related.
* The forall'd binders for SPECIALISE are the same as those for a RULE, so I
refactored, introducing data type `L.H.S.Binds.RuleBndrs`, with functions
to rename, zonk, typecheck it. I refactored this data type a bit; nicer now.
* On the LHS of RULES, or SPECIALISE, we want to disable the tricky mechanims
described in Note [Desugaring non-canonical evidence] in GHC.HsToCore.Expr.
Previously it wasn't fully disabled (just set to the empty set), and that
didn't quite work in the new regime.
* There are knock-on changes to Template Haskell.
* For the LHS of a RULE and a SPECIALISE expression, I wanted to simplify
it /without/ inlining the let-bindings for evidence variables. I added
a flag `so_inline` to the SimpleOpt optimiser to support this. The
entry point is `GHC.Core.SimpleOpt.simpleOptExprNoInline`
* Since forever we have had a hack for type variables on the LHS of
RULES. I took the opportunity to tidy this up. The main action is
in the zonker. See GHC.Tc.Zonk.Type Note [Free tyvars on rule LHS],
and especially data construtor `SkolemiseFlexi`
in data type `GHC.Tc.Zonk.Env.ZonkFlexi`
* Move `scopedSort` from GHC.Core.TyCo.FVs to GHC.Core.Predicate
Reason: it now works for Ids as well, and I wanted to use isEvVar,
which is defined in GHC.Core.Predicate
Avoiding module loops meant that instead of exporting GHC.Core.TyCo.Tidy
from GHC.Core.Type, modules now import the former directly.
I also took the opportunity to remove unused exports
from GHC.Core.Type.hs-boot
* Flag stuff:
- Add flag `-Wdeprecated-pragmas` and use it to control the warning when
using old-style SPECIALISE pragmas with multiple type ascriptions,
- Add flag `-Wuseless-specialisations` and use it to control the warning emitted
when GHC determines that a SPECIALISE pragma would have no effect. Don't
want if the SPECIALISE is SPECIALISE INLINE (#4444)
In response to #25389, we continue to generate these seemingly code for these
seemingly useless SPECIALISE pragmas
- Adds deprecations to Template Haskell `pragSpecD` and `pracSpecInlD`,
* Split up old-style SPECIALISE pragmas in GHC.Internal.Float,
GHC.Internal.Numeric, GHC.Internal.Real
* Remove useless SPECIALISE pragmas in Data.Array (updating the array submodule)
Smaller things:
- Update the Users Guide
- Add mention of the changes to the 9.14 release notes as well as
the Template Haskell changelog,
-
1884dd1a
by Simon Peyton Jones at 2025-03-18T20:05:03-04:00
Add -Wrule-lhs-equalities warning
This commit adds a new warning, controlled by the warning flag,
-Wrule-lhs-equalities, which is emitted when the LHS of a RULE gives
rise to equality constraints that previous GHC versions would have
quantified over.
GHC instead discards such RULES, as GHC was never able to generate
a rule template that would ever fire; it's better to be explicit about
the fact that the RULE doesn't work.
-
b00b3ef0
by Ben Gamari at 2025-03-18T20:05:41-04:00
compiler: Add export list to GHC.SysTools.Process
This also revealed that `readProcessEnvWithExitCode` and its local
helpers were dead code.
-
25850b22
by ARATA Mizuki at 2025-03-18T20:06:25-04:00
Fix code generation for SSE vector operations
The new implementation generates correct code
even if the registers overlap.
Closes #25859
-
e576468c
by Andreas Klebinger at 2025-03-18T20:07:02-04:00
Bump nofib submodule.
Fixes #25867. (Ben-raytrace being broken by library changes)
-
443fc8b1
by Sjoerd Visscher at 2025-03-19T12:01:04-04:00
Multiplicity annotation on records
Needing to store multiplicity annotations on records triggered a refactoring of AST of data declarations:
Moved HsBangTy and HsRecTy from HsType to HsTypeGhcPsExt, the extension of HsType during parsing, since they are only needed during parsing.
New HsConDeclField that stores all source data shared by all constructor declaration fields: unpackedness, strictness, multiplicity, documentation and the type of the field.
Merged HsMultAnn and HsArrowOf, so all multiplicity annotations share the same data type.
HsBang was no longer needed as a separate type, and was inlined into HsSrcBang.
-
313cf271
by Ben Gamari at 2025-03-19T12:01:43-04:00
gitlab-ci: Drop CentOS 7 binary distributions
CentOS 7 is EoL and moreover we cannot even build images for it.
See #25061.
-
5b94f99f
by Ben Gamari at 2025-03-19T12:02:21-04:00
rts: Ensure that WinIO flag is set when --io-manager=auto
As noted in #25838, previously `selectIOManager` failed to set
`rts_IOManagerIsWin32Native` in its `IO_MNGR_FLAG_AUTO`. This meant
that the MIO path was taken when WinIO was supposedly selected,
resulting in chaos.
Fixes #25838.
-
1a3f1131
by Peng Fan at 2025-03-19T12:03:10-04:00
Pass the mcmodel=medium parameter to CC via GHC
Ensure that GHC-driver builds default to mcmodel=medium, so that GHC
passes this default parameter to CC without having to add it to the
compiled project.
Commit e70d41406b5d5638b42c4d8222cd03e76bbfeb86 does not ensure that all
GHC-built object files have a default model of medium, and will raise an
R_LARCH_B26 overflow error.
-
27cf7361
by Matthew Craven at 2025-03-19T12:03:48-04:00
Add interface-stability test for ghc-bignum
As with ghc-prim, it makes sense to have some protection against
accidental interface changes to this package caused by changes
in ghc-internal.
-
25d46547
by Matthew Craven at 2025-03-19T12:03:48-04:00
Add README reference for the interface-stability tests
-
5d65393e
by Simon Peyton Jones at 2025-03-20T05:41:24-04:00
Remove the Core flattener
This big MR entirely removes the "flattener" that took a type and
replaced each type-family application with a fresh type variable.
The flattener had its origin in the paper
Injective type families for Haskell
But (a) #25657 showed that flattening doesn't really work.
(b) since we wrote the paper we have introduced the so-called
"fine-grained" unifier GHC.Core.Unify, which can return
* SurelyApart
* Unifiable subst
* MaybeApart subst
where the MaybeApart says that the two types are not unifiable by a
substitution, but could (perhaps) be unified "later" after some type
family reductions. This turns out to subsume flattening.
This MR does a major refactor of GHC.Core.Unify to make it capable of
subsuming flattening. The main payload is described in
Note [Apartness and type families]
and its many wrinkles.
The key (non-refactoring) implementation change is to add `um_fam_env`
to the `UMState` in the unification monad.
Careful review with Richard revealed various bugs in the treament of
`kco`, the kind coercion carried around by the unifier, so that is
substantially fixed too: see Note [Kind coercions in Unify].
Compile-time performance is improved by 0.1% with a few improvements over
1% and one worsening by 1.3% namely T9872a. (I have not investigated the
latter.)
Metric Decrease:
T9872b
T9872c
TcPlugin_RewritePerf
Metric Increase:
T9872a
-
9003ef0a
by sheaf at 2025-03-20T05:42:08-04:00
Remove SDoc from UnknownSubordinate/MissingBinding
This commit replaces unstructured SDoc arguments in error message constructors
with uses of the following two datatypes:
- SigLike: for different kinds of signatures (e.g. standalone kind signatures,
fixity signatures, COMPLETE pragmas, etc)
- Subordinate: for class methods, associated types, and record fields
The following error message constructors now no longer have any SDocs in them:
- TcRnIllegalBuiltinSyntax: SDoc -> SigLike
- MissingBinding: SDoc -> SigLike
- UnknownSubordinate: SDoc -> (Name, Subordinate)
- SuggestMoveToDeclarationSite: SDoc -> SigLike
-
4329f3b6
by sheaf at 2025-03-20T05:42:08-04:00
Remove SDocs from HsDocContext
This commit removes the remaining SDocs from the HsDocContext data type.
It adds the following constructors:
ClassInstanceCtx -- Class instances
ClassMethodSigCtx -- Class method signatures
SpecialiseSigCtx -- SPECIALISE pragmas
PatSynSigCtx -- Pattern synonym signatures
We now report a bit more information for errors while renaming class instances,
which slightly improves renamer-emitted error messages.
-
75c29aa1
by sheaf at 2025-03-20T05:42:08-04:00
Reject instance with non-class head in renamer
This commit modifies rnClsInstDecl so that, when renaming, we reject a class
instance declaration in which the head is not a class. Before this change, it
would get rejected in the type-checker, but that meant that the renamer could
emit unhelpful error messages, e.g.:
data Foo m a
instance Foo m where
fmap _ x = case x of
would rather unhelpfully say:
‘fmap’ is not a (visible) method of class ‘Foo’
when of course 'Foo' is not even a class. We now reject the above program
with the following error message:
Illegal instance for data type ‘Foo’.
Instance heads must be of the form
C ty_1 ... ty_n
where ‘C’ is a class.
Fixes #22688
-
a8f543a9
by Cheng Shao at 2025-03-20T18:47:19-04:00
testsuite: mark T7919 as fragile on i386 as well
T7919 may also fail i386 CI jobs with test timeout.
-
256ac29c
by sheaf at 2025-03-20T18:48:07-04:00
Don't cache solved [W] HasCallStack constraints
This commit ensures we do not add solved Wanted constraints that mention
HasCallStack or HasExceptionContext constraints to the set of solved
Wanted dictionary constraints: caching them is invalid, because re-using
such cached dictionaries means using an old call-stack instead of
constructing a new one, as was reported in #25529.
Fixes #25529.
-
47646ce2
by Andrew Lelechenko at 2025-03-20T18:48:43-04:00
Improve haddock-visible documentation for GHC.Driver.Flags
-
2e4e15ed
by Sylvain Henry at 2025-03-21T17:49:36-04:00
Document -fnum-constant-folding (#25862)
-
044a6e08
by sheaf at 2025-03-21T17:50:24-04:00
LLVM: fix typo in padLiveArgs
This commit fixes a serious bug in the padLiveArgs function, which
was incorrectly computing too many padding registers. This caused
segfaults, e.g. in the UnboxedTuples test.
Fixes #25770
Fixes #25773
-
1745c749
by Teo Camarasu at 2025-03-22T18:42:37-04:00
template-haskell: remove Language.Haskell.TH.Lib.Internal
This module is purely used for the implementation of TH quote
desugarring.
Historically this needed to be exposed from `template-haskell`, since
that's the package that the desugarred expressions referenced but since
https://gitlab.haskell.org/ghc/ghc/-/merge_requests/12479, this is no
longer the case.
Now these identifiers are in `ghc-internal`.
Note that this module has carried the following warning for a long time:
> This is not a part of the public API, and as such, there are no API guarantees for this
module from version to version.
Resolves #24766
-
3bc507db
by Alan Zimmerman at 2025-03-22T18:43:13-04:00
EPA: Fix exact printing of SPECIALISE pragma
This commit fixes two minor issues with exactprinting of the
SPECIALISE pragma after !12319 landed
- The span for the RHS did not include the optional signature type
- The `::` was printed twice when the legacy path was used
Closes #25885
-
bdf93da8
by sheaf at 2025-03-24T11:25:12+01:00
Renamer: improve handling of export children
This commit refactors the 'childGREPriority' function which is used when
renaming subordinate items in export lists and class declarations.
Instead of having a complicated LookupChild parameter, we now simply pass the
GREInfo of the parent, which allows us to decide what is a valid child:
- classes can have children that are in the type constructor namespace,
- promoted data constructors should be treated the same as normal data
constructors.
Fixes #24027
-
1dbc7846
by Matthew Pickering at 2025-03-24T15:35:17-04:00
Revert "mk-ghcup-metadata: Clean up and add type annotations"
This reverts commit 64ea68d9a206ec4db5020b0a3fc563199ab18be3.
See #25889
-
6941c825
by doyougnu at 2025-03-25T10:05:58-04:00
base: construct compat RTSFlags
-- see CLC #289
-
730e6f77
by doyougnu at 2025-03-25T10:06:02-04:00
base: construct compat GHC.Stats
-- see CLC #289
-
cd9e6605
by Ben Gamari at 2025-03-25T17:59:52-04:00
rel_eng/upload: Clarify usage directions
Previously it was not made clear that the directory name is significant.
-
7d18c19b
by Cheng Shao at 2025-03-25T22:00:56+00:00
ghci: make the Pipe type opaque
This commit makes the Pipe type in ghci opaque, and introduce the
mkPipeFromHandles constructor for creating a Pipe from a pair of
Handles. Pipe is now just a pair of receiver/sender continuations
under the hood. This allows a Pipe to be potentially backed by other
IPC mechanisms (e.g. WebSockets) which is essential for wasm ghci
browser mode.
-
a2103fd2
by Cheng Shao at 2025-03-25T22:00:56+00:00
ghci: use improved Pipe logic for wasm iserv
This commit makes wasm iserv take advantage of the Pipe refactoring by
passing binary receiver/sender js callbacks from the dyld script. This
paves the way for piping the binary messages through WebSockets in
order to run wasm iserv in the browser, but more importantly, it
allows us to get rid of a horrible hack in the dyld script: we no
longer have to fake magical wasi file descriptors that are backed by
nodejs blocking I/O! The legacy hack was due to these facts:
- iserv only supported exchanging binary messages via handles backed
by file descriptors
- In wasi you can't access host file descriptors passed by host ghc
- The nodejs wasi implementation only allows mapping host directories
into the wasi vfs, not host file descriptors
- Named pipes with file paths (mkfifo) doesn't work well with nodejs
wasi implementation, causes spurious testsuite failures on macos
But starting from this point, we can fully take advantage of
non-blocking I/O on the js side.
-
fa2fbd2b
by Cheng Shao at 2025-03-25T22:00:56+00:00
ghci: fix ^C handling for wasm iserv
This commit fixes ^C handling for wasm iserv. Previously we didn't
handle it at all, so ^C would kill the node process and host ghc would
then crash as well. But native ghc with external interpreter can
handle ^C just fine and wasm should be no different. Hence the fix:
wasm iserv exports its signal handler as a js callback to be handled
by the dyld script. Also see added note for details.
-
efcebed6
by Cheng Shao at 2025-03-25T22:00:56+00:00
wasm: fix post-link.mjs for browser
The wasm ghci browser mode needs to run dyld.mjs in the browser which
imports post-link.mjs. This script makes post-link.mjs runnable in the
browser by deferring node-specific module imports to their actual use
sites.
-
27bb73c6
by Cheng Shao at 2025-03-25T22:00:56+00:00
wasm: use console.assert in dyld script
This commit uses console.assert() instead of node-specific strict
assert in the dyld script, in order to make it runnable in the
browser. console.assert() only warns and doesn't crash upon assertion
failure, but this is fine; we can always trivially define a strict
assert function shall it be necessary when debugging, and there hasn't
been such an assertion failure seen in the wild for long enough.
-
929df0ba
by Cheng Shao at 2025-03-25T22:00:56+00:00
wasm: asyncify the dylink.0 custom section parser
This commit refactors the simple binary parser in the dyld script in
charge of parsing the dylink.0 custom section. Previously the parser
was synchronous and operated on the entire input buffer; this was
simple and easy and worked well enough when the input wasm modules are
instantly read from local filesystem.
However, when running dyld in the browser, the wasm modules are
transferred via fetch() requests. The host ghc and the browser might
not be on the same machine, so slow network uplink does need to be
considered. We only need to parse dylink.0 custom section to extract
dependency info, and dylink.0 is the very first custom section in the
wasm shared library binary payload, so the parsing process should not
require fetch() to complete and should return the parsing result asap.
Hence the refactorings in this commit: asyncify the parser, make it
only consume as many bytes as needed by invoking an async consumer
callback. The input is a readable stream from the fetch() response;
once the response is available, the async wasm compilation can start
in the background, and dylink.0 parsing shall end asap which results
in more wasm shared libraries to be loaded earlier. Profit.
-
9a697181
by Cheng Shao at 2025-03-25T22:00:56+00:00
wasm: fix dyld setImmediate usage in browser
The wasm dyld script used to only run in node and directly uses
setImmediate in globalThis. In case of browsers, it needs to import
setImmediate from the prelude, hence this commit.
-
d9b71e82
by Cheng Shao at 2025-03-25T22:00:57+00:00
wasm: fix dyld downsweep filepath handling in browser
The wasm dyld downsweep logic used to rely on nodejs path module to
handle filepaths. That's not available in browsers, so this commit
implements poor man's filepath handling in js, which is not elegant
for sure but works for both nodejs and the browser.
-
7003a399
by Cheng Shao at 2025-03-25T22:00:57+00:00
wasm: isolate nodejs-specific logic with the isNode flag in dyld
As we move towards supporting running the dyld script in the browser,
this commit implements the isNode module-level binding which is true
if dyld is running in nodejs. The nodejs-specific bits are gated under
isNode.
For the browser case, this commit introduces @bjorn3/browser_wasi_shim
as the wasi implementation; we already use it in quite a few projects
and it simply works.
-
22ba2a78
by Cheng Shao at 2025-03-25T22:00:57+00:00
wasm: isolate dyld side effects that might require IPC
This commit spins out a DyLDHost class from DyLD that handles side
effects that must be run in the same host environment that runs
wasm32-wasi-ghc. When the dyld script runs in the browser, it'll need
to do IPC to find libraries, fetch wasm library, etc, and the other
side of dyld that runs on nodejs would simply expose the DyLDHost
methods as endpoints for WebSockets/HTTP.
-
e93fc33d
by Cheng Shao at 2025-03-25T22:00:57+00:00
wasm: implement wasm ghci browser mode
This commit implements the rest of dyld logic that delivers the ghci
browser mode:
- The dyld script can now fully run in the browser. It communicates
back with dyld-on-nodejs via WebSockets and also plain HTTP 1.1
requests.
- The host dyld starts a server and acts as a broker between the GHC
process and the browser side. GHC doesn't need to know anything
about the browser mode; no driver flags need to be added and no
recompilation needs to happen, the GHC driver continues to use the
original iserv binary messages protocol.
- The dyld broker doesn't need to parse any message between the
browser dyld and GHC; it merely sets up WebSockets connections to
redirect these messages as well as ^C signals.
- Plain HTTP 1.1 is used for IPC requests (e.g. downloading a wasm
module).
- The dyld broker serves a main.js script that bootstraps iserv in the
browser, and a main.html empty page playground for testing. CORS is
enabled so it could be possible to inject iserv into other websites
and use ghci to play with them.
- All the RPC logic is opaque to the DyLD class, the majority of the
wasm dynamic linker code is already portable and runs fine in
firefox/chrome/webkit.
Closes #25399.
-
fc576798
by Cheng Shao at 2025-03-25T22:00:57+00:00
wasm: add puppeteer/playwright support for ghci browser mode
This commit adds support for using puppeteer/playwright for
automatically launching a headless browser that backs the ghci browser
mode. This is useful for testing the ghci browser mode as a part of
GHC testsuite, and it's also convenient for local development since
the step to start iserv can be automated away.
-
ad7e271d
by Cheng Shao at 2025-03-25T22:00:57+00:00
wasm: support wasi console redirect for the ghci browser mode
This commit adds optional support for redirecting wasi console
stdout/stderr back to the host when running wasm ghci browser mode. By
default, the wasi console outputs are only available under F12
devtools console, but in case of testing against a mobile browser, the
devtools console may not be readily available, and it would be more
convenient to at least get wasi console output on the host side.
The redirection logic is simple, just adding another two WebSockets
connections that pump the line-buffered textual messages back to
host.
-
731217ce
by Cheng Shao at 2025-03-25T22:00:57+00:00
wasm: add brotli compression for ghci browser mode
This commit adds brotli compression for wasm shared libraries for ghci
browser mode. With BROTLI_MIN_QUALITY, the overhead is negligible, and
it helps reducing amount of transferred data when the browser connects
to the server over a slow connection.
-
ac70e643
by Cheng Shao at 2025-03-26T13:37:19+00:00
testsuite: add browser001 test for wasm ghci browser mode
This commit adds support for testing the wasm ghci browser mode in the
testsuite, as well as a simple first test case browser001 that makes
use of TH, JSFFI and browser-specific DOM API. See added note and
comments for details.
-
6ef5c0d2
by Cheng Shao at 2025-03-26T13:37:24+00:00
docs: add wasm ghci subsection in user manual
This commit updates the user manual to add wasm ghci subsection.
-
37381bcf
by Cheng Shao at 2025-03-26T13:37:24+00:00
docs: update Note [The Wasm Dynamic Linker]
This commit updates Note [The Wasm Dynamic Linker] to reflect recent
developments, in particular the wasm ghci browser mode.
-
4b5a0f61
by Cheng Shao at 2025-03-26T13:37:24+00:00
ci: bump DOCKER_REV and test wasm ghci browser mode
This commit bumps the ci-images revision for updated wasm toolchain,
and adds the launch options required to test wasm ghci browser mode.
-
c6a3bc8f
by Cheng Shao at 2025-03-26T13:37:24+00:00
driver: implement wasm ghci browser mode flags
This commit implements GHC driver flags that enable the wasm ghci
browser mode.
-
f75e823e
by Cheng Shao at 2025-03-26T18:01:54-04:00
rts: add hs_try_putmvar_with_value to RTS API
This commit adds hs_try_putmvar_with_value to rts. It allows more
flexibility than hs_try_putmvar by taking an additional value argument
as a closure to be put into the MVar. This function is used & tested
by the wasm backend runtime, though it makes sense to expose it as a
public facing RTS API function as well.
-
9cd9f347
by Cheng Shao at 2025-03-26T18:01:54-04:00
wasm: use MVar as JSFFI import blocking mechanism
Previously, when blocking on a JSFFI import, we push a custom
stg_jsffi_block stack frame and arrange the `promise.then` callback to
write to that stack frame. It turns out we can simply use the good old
MVar to implement the blocking logic, with a few benefits:
- Less maintenance burden. We can drop the stg_jsffi_block related Cmm
code without loss of functionality.
- It interacts better with existing async exception mechanism. throwTo
would properly block the caller if the target thread is masking
async exceptions.
-
da34f0aa
by Cheng Shao at 2025-03-26T18:01:54-04:00
wasm: properly pin the raiseJSException closure
We used to use keepAlive# to pin the raiseJSException closure when
blocking on a JSFFI import thunk, since it can potentially be used by
RTS. But raiseJSException may be used in other places as well (e.g.
the promise.throwTo logic), and it's better to simply unconditionally
pin it in the JSFFI initialization logic.
-
dc904bfd
by Cheng Shao at 2025-03-26T18:01:54-04:00
wasm: implement promise.throwTo() for async JSFFI exports
This commit implements promise.throwTo() for wasm backend JSFFI
exports. This allows the JavaScript side to interrupt Haskell
computation by raising an async exception. See subsequent docs/test
commits for more details.
-
7f80455e
by Cheng Shao at 2025-03-26T18:01:55-04:00
testsuite: add test for wasm promise.throwTo() logic
This commit adds a test case to test the wasm backend
promise.throwTo() logic.
-
afdd3fe7
by Cheng Shao at 2025-03-26T18:01:55-04:00
docs: document the wasm backend promise.throwTo() feature
-
65dc65dc
by sheaf at 2025-03-26T18:02:43-04:00
Refactor CtEvidence into Given/Wanted
This commit is a simple refactoring which splits up the CtEvidence,
giving each constructor its own datatype:
data CtEvidence
= CtGiven GivenCtEvidence
| CtWanted WantedCtEvidence
data GivenCtEvidence =
GivenCt
{ ctev_pred :: TcPredType
, ctev_evar :: EvVar
, ctev_loc :: CtLoc }
data WantedCtEvidence =
WantedCt
{ ctev_pred :: TcPredType
, ctev_dest :: TcEvDest
, ctev_loc :: CtLoc
, ctev_rewriters :: RewriterSet }
This enables a few minor simplifications in the code, notably removing
a panic from GHC.Tc.Solver.Solve.solveWantedForAll_implic.
Fixes #25848
-
ada04031
by sheaf at 2025-03-26T18:03:27-04:00
Export lists: same prio for NoParent & RightParent
This commit ensures that, when we are renaming children in an export
list item such as
module M ( P(A,B,C) )
we consider children with NoParent to have the same priority as children
which have the correct parent (P in this case). This is because we
should **not** prioritise a data constructor (with the right parent)
over a pattern synonym we are bundling (which, before bundling, has
no parent).
Fixes #25892
-
721628a0
by Adriaan Leijnse at 2025-03-27T09:10:10-04:00
TTG: Replace HsUnboundVar with HsHole
Context:
The HsUnboundVar constructor in Language.Haskell.Syntax.Expr contained a
RdrName, which stood in the way of the work towards a dedicated
haskell-syntax library. The constructor was overloaded for unbound
variables, anonymous and named holes, and parse errors.
This commit:
Replaces HsUnboundVar with HsHole. In the surface syntax HsHole only
represents an anonymous expression hole ("_"). It is extended with the
XHole type family.
In the concrete GHC implementation of the language on the other hand,
HsHole is used for "any thing which is not necessarily a valid or fully
defined program fragment, but for which a type can be derived". This use
is similar to how HsUnboundVar was used, but the parse error case is now
made explicit with a ParseError case for XHole. This is in anticipation
of future work on a fault tolerant compilation pipeline.
-
dbd852f5
by Ben Gamari at 2025-03-27T09:10:48-04:00
rel_eng: Finish removal of CentOS jobs
Remove centos7 from release fetch and ghcup metadata generation scripts.
Closes #25893.
-
0e0231e7
by Matthew Pickering at 2025-03-28T18:36:33-04:00
hadrian: Make hash_unit_ids into a flavour transformer (and enable for release flavour)
The primary reason for this change is to make the `release` flavour
enable `--hash-unit-ids` by default without any further user intervention.
* Packagers don't have to be aware of this special flag they should be
using.
* release builds on CI are uniformly testing with hashes (see !13418)
Fixes #25379
-
9fc54c12
by Rodrigo Mesquita at 2025-03-28T18:37:10-04:00
driver: Move DynFlags consistency fixes off Main
These consistency fixes found in Main.hs are required for the proper
functioning of the compiler and should live together with all remaining
fixes in `makeDynFlagsConsistent`.
This is especially relevant to GHC applications that shouldn't have to
copy/fix themselves possibly inconsistent DynFlags.
Additionally, outputs information when verbosity is high about these
consistency fixes that were previously quiet, adds information to the
Note on consistency of DynFlags, and improves one of the fixes that
incorrectly used `dynNow`.
-
2fdd0be9
by sheaf at 2025-03-28T18:37:53-04:00
Remove GhcHint from TcRnNotInScope constructor
This is a tiny refactoring which:
- removes GhcHint/ImportError fields from some constructors of
TcRnMessage, using the TcRnMessageDetailed mechanism instead to
report this informaiton:
- removes the GhcHint and ImportErrors fields from TcRnNotInScope
- removes the GhcHint field from TcRnTermNameInType
- ensures that we only include these hints and import errors when the
-fhelpful-errors flag is turned on
Fixes #25874
-
9e5cd064
by ARATA Mizuki at 2025-03-31T14:53:34-04:00
Better support for SSE3 and SSE4.1
In particular:
* Pass appropriate attributes to LLVM
* Define preprocessor macros for them
-
c2c7dd51
by ARATA Mizuki at 2025-03-31T14:53:34-04:00
x86: Add support for SSSE3
This commit adds the `-mssse3` flag, which controls usage of SSSE3 instructions in x86 code generation.
-
d7c62580
by ARATA Mizuki at 2025-03-31T14:53:34-04:00
x86 NCG SIMD: Implement 128-bit integer vector arithmetics
This commit implements the following operations on integer vectors:
* negateIntNXM#
* plus{Int,Word}NXM#
* minus{Int,Word}NXM#
* times{Int,Word}NXM#
* quot{Int,Word}NXM#
* rem{Int,Word}NXM#
* min{Int,Word}NXM#
* max{Int,Word}NXM#
where (N,M) is one of (8,16), (16,8), (32,4), or (64,2).
Closes #25643
-
f5ea4e7e
by ARATA Mizuki at 2025-03-31T14:53:34-04:00
x86 NCG SIMD: Implement 128-bit integer vector shuffle
This commit implements the following operations:
* shuffle{Int,Word}8X16#
* shuffle{Int,Word}16X8#
* shuffle{Int,Word}32X4#
* shuffle{Int,Word}64X2#
See #25643
-
5eeb6645
by Simon Peyton Jones at 2025-03-31T14:54:16-04:00
Re-jig the way that the Simplifier tries RULES
As #25170 showed, if a new RULE appears, it could change the simplifier's
behaviour a bit, even if it never fires; and that messes up deterministic
compilation. (This was particularly nasty if the rule wasn't even transitively
below the module being compiled.)
This MR rejigs the use of `tryRules` so that behaviour does not change
when a new, unrelated RULE is added. It's described in
* Note [When to apply rewrite rules]
* Note [tryRules: plan (BEFORE)]
* Note [tryRules: plan (AFTER)]
The main change is in the refactored version of
* simplOutId
* rebuildCall
The little state machine that was embedded in ArgInfo is gone.
As I wandered around the Simplifier I also found opportunities for
some loosely-related refactoring:
* In several places, the /substitution/ in the SimpleEnv is empty;
all we care about is the in-scope set and the flags. So
- I made a synonym `SimplEnvIS` that embodies that invariant,
- used it in a number of type signatures (notably `rebuild`)
- added some assertion checks (via `checkSimlEnvIS`)
* I moved the hanlding of `runRW` out of `rebuildCall` (where we
would have to test repeatedly) and into the new `simplOutId`, which
fires up `rebuildCall`. Now it is only tested once.
-------------------------
Metric Decrease:
T9020
T9961
-------------------------
-
f534474a
by sheaf at 2025-03-31T14:54:59-04:00
Add comment: no qualified Names in the LocalRdrEnv
This commit adds a reference to section 5.5.1 of the Haskell 2010 report,
to explain that qualified names can't occur in the LocalRdrEnv.
Fixes #25875
-
d5ea80c6
by Patrick at 2025-03-31T14:55:42-04:00
Fix deadlock/loop in interface rehydration (#25858)
In #25858, GHC hangs when processing modules with class defaults due to a
circular dependency in the interface rehydration process. The deadlock/loop
occurred when eager class defaults rehydration accessed not-yet-complete module details.
To fix the immediate deadlock/loop.
`tcIfaceDefaults` is refactored, we use the class name directly from the iface
and use `forM` for lazy loading the class, which algins with the handling of other fields
of ModDetails. This laziness ensure rehydration waits for HomePackageTable (HPT) to
be updated and prevent premature evaluation of ModDetails inside `fixIO``.
As suggested by Matthew, class defaults importing is also refactored
to align with the compiler's established interface loading conventions.
- add class defaults field to ExternalPackageState (EPS).
- rehydrate and store class defaults in EPS at `loadInterface`.
- Instead of using `tcIfaceDefaults` in `tcRnImports`, we add and use
`tcGetClsDefaults` to read defaults directly from HPT or EPS
when importing modules.
Tests:
- T25858, T25858v1-2: Test class hydration in defaults
- T25858v3-4: Test type list hydration in defaults
New Note [Tricky rehydrating IfaceDefaults loop] is added.
Thanks to @sheaf (Sam), @mpickering (Matthew), and @simonpj (Simon) for their
valuable input and analysis.
Fixes #25858.
-
2d419d8d
by Matthew Pickering at 2025-04-02T16:12:36-04:00
Use unsafePerformIO in definition of computeFingerprint
computeFingerprint is morally a pure function, which is implemented by
mutating a buffer. Using unsafePerformIO inside the definition allows it
to be used in pure contexts, fixing one place where an ad-hoc call to
unsafePerformIO is already needed.
-
ccdf979b
by Matthew Pickering at 2025-04-02T16:12:37-04:00
driver: Fix recompilation checking for exported defaults
Since the exported defaults are not associated with any identifier from
the module, they are just added to the export hash rather than
the fine-grained recompilation logic.
Fixes #25855
-
c5bf9892
by Matthew Pickering at 2025-04-02T16:12:37-04:00
driver: Fix recompilation checking for COMPLETE pragmas
A {-# COMPLETE P, Q #-} pragma is associated with the pattern synonyms P
and Q during recompilation checking. Therefore, the existence of a
pattern synonym becomes part of the ABI hash for P and Q.
Then if a module uses these pattern synonyms and a complete pragma
changes, it will trigger recompilation in that module.
Fixes #25854
-
d0fd9370
by sheaf at 2025-04-02T16:14:05-04:00
Handle named default exports separately
This commit changes the way we check for duplicate exports of named
default declarations. They are now treated entirely separately from
other exports, because in an export list of the form
module M ( default Cls, Cls )
the default declaration does not export the class 'Cls', but only its
default declarations.
Also fixes a bug in Backpack where named default exports were getting
dropped entirely. No test for that.
Fixes #25857
-
62d04494
by Cheng Shao at 2025-04-03T05:56:17-04:00
ci: add x86_64-linux-ubuntu24_04 nightly/release jobs
-
327952e4
by Cheng Shao at 2025-04-03T05:56:17-04:00
rel-eng: add ubuntu24_04 bindists to ghcup metadata and fetch gitlab scripts
-
aa1e3b8b
by sheaf at 2025-04-03T05:57:24-04:00
GHC settings: always unescape escaped spaces
In #25204, it was noted that GHC didn't properly deal with having
spaces in its executable path, as it would compute an invalid path
for the C compiler.
The original fix in 31bf85ee49fe2ca0b17eaee0774e395f017a9373 used a
trick: escape spaces before splitting up flags into a list. This fixed
the behaviour with extra flags (e.g. -I), but forgot to also unescape
for non-flags, e.g. for an executable path (such as the C compiler).
This commit rectifies this oversight by consistently unescaping the
spaces that were introduced in order to split up argument lists.
Fixes #25204
-
34a9b55d
by lazyLambda at 2025-04-04T06:22:26-04:00
Driver: make MonadComprehensions imply ParallelListComp
This commit changes GHC.Driver.Flags.impliedXFlags to make the
MonadComprehensions extension enable the ParallelListComp extension.
Fixes #25645
-
d99eb7cd
by sheaf at 2025-04-04T06:23:28-04:00
NamedDefaults: handle poly-kinded unary classes
With this commit, we accept named default declarations for poly-kinded
classes such as Typeable, e.g.
default Typeable (Char)
This used to fail because we assumed the kind of the class was monomorphic,
e.g.
Type -> Constraint
(Type -> Type) -> Constraint
Nat -> Constraint
Now, we can handle a simple polymorphic class such as
Typeable :: forall k. k -> Constraint
Note that we keep the restriction that the class must only have
one visible argument.
This is all explained in the new Note [Instance check for default declarations]
in GHC.Tc.Gen.Default.
Fixes #25882
-
4cbc90de
by sheaf at 2025-04-04T11:39:05-04:00
LLVM: add type annotations to AtomicFetch_cmm.cmm
-
e2237305
by sheaf at 2025-04-04T11:39:05-04:00
Cmm lint: lint argument types of CallishMachOps
This commit adds a new check to Cmm lint to ensure that the argument
types to a CallishMachOp are correct. The lack of this check was
detected in the AtomicFetch test: the literals being passed as the
second arguments to operations such as 'fetch_add', 'fetch_and'... were
of the wrong width, which tripped up the LLVM backend.
-
9363e547
by Cheng Shao at 2025-04-04T11:39:50-04:00
ci: add ghc-wasm-meta integration testing jobs
This patch adds ghc-wasm-meta integration testing jobs to the CI
pipeline, which are only triggered via the `test-wasm` MR label or
manually when the `wasm` label is set.
These jobs will fetch the wasm bindists and test them against a
variety of downstream projects, similarly to head.hackage jobs for
native bindists, offering a convenient way to catch potential
downstream breakage while refactoring the wasm backend.
-
27029e60
by Adam Gundry at 2025-04-04T11:40:36-04:00
base: Minor fixes to GHC.Records haddocks
This corrects a stale reference to OverloadedRecordFields (which should
be OverloadedRecordDot), fixes the haddock link syntax and adds an
@since pragma.
-
f827c4c6
by Rodrigo Mesquita at 2025-04-07T11:22:10-04:00
Parametrize default logger action with Handles
Introduce `defaultLogActionWithHandles` to allow GHC applications to use
GHC's formatting but using custom handles.
`defaultLogAction` is then trivially reimplemented as
```
defaultLogActionWithHandles stdout stderr
```
-
5dade5fd
by sheaf at 2025-04-07T11:23:02-04:00
Finer-grained recompilation checking for exports
This commit refines the recompilation checking logic, to avoid
recompiling modules with an explicit import list when the modules they
import start exporting new items.
More specifically, when:
1. module N imports module M,
2. M is changed, but in a way that:
a. preserves the exports that N imports
b. does not introduce anything that forces recompilation downstream,
such as orphan instances
then we no longer require recompilation of N.
Note that there is more to (2a) as initially meets the eye:
- if N includes a whole module or "import hiding" import of M,
then we require that the export list of M does not change,
- if N only includes explicit imports, we check that the imported
items don't change, e.g.
- if we have @import M(T(K, f), g)@, we must check that N
continues to export all these identifiers, with the same Avail
structure (i.e. we should error if N stops bundling K or f with
T)
- if we have @import M(T(..))@, we must check that the children
of T have not changed
See Note [When to recompile when export lists change?] in GHC.Iface.Recomp.
This is all tested in the new tests RecompExports{1,2,3,4,5}
Fixes #25881
-
f32d6c2b
by Andreas Klebinger at 2025-04-07T22:01:25-04:00
NCG: AArch64 - Add -finter-module-far-jumps.
When enabled the arm backend will assume jumps to targets outside of the
current module are further than 128MB away.
This will allow for code to work if:
* The current module results in less than 128MB of code.
* The whole program is loaded within a 4GB memory region.
We have seen a few reports of broken linkers (#24648) where this flag might allow
a program to compile/run successfully at a very small performance cost.
-------------------------
Metric Increase:
T783
-------------------------
-
553c280b
by Andreas Klebinger at 2025-04-07T22:02:11-04:00
Revert "rts: fix small argument passing on big-endian arch (fix #23387)"
Based on analysis documented in #25791 this doesn't fully fix the big
while introducing new bugs on little endian architectures.
A more complete fix will have to be implemented to fix #23387
This reverts commit 4f02d3c1a7b707e609bb3aea1dc6324fa19a5c39.
-
b0dc6599
by Andreas Klebinger at 2025-04-07T22:02:11-04:00
Interpreter: Fixes to handling of subword value reads/writes.
Load subword values as full words from the stack truncating/expanding as
neccesary when dealing with subwords. This way byte order is implicitly
correct.
This commit also fixes the order in which we are pushing literals onto
the stack on big endian archs.
Last but not least we enable a test for ghci which actually tests these
subword operations.
-
ed38c09b
by Cheng Shao at 2025-04-07T22:02:53-04:00
testsuite: don't test WasmControlFlow stdout
This patch solves a potential test flakiness in `WasmControlFlow` by
removing `WasmControlFlow.stdout` which is not so portable/stable as
it seems. See added `Note [WasmControlFlow]` for more detailed
explanation.
-
f807c590
by Rodrigo Mesquita at 2025-04-08T17:41:51-04:00
debugger: Add docs to obtainTermFromId
-
5dba052d
by Rodrigo Mesquita at 2025-04-08T17:41:51-04:00
Move logic to find and set Breakpoint to GHC
Breakpoints are uniquely identified by a module and an index unique
within that module. `ModBreaks` of a Module contains arrays mapping from
this unique breakpoint index to information about each breakpoint. For
instance, `modBreaks_locs` stores the `SrcSpan` for each breakpoint.
To find a breakpoint using the line number you need to go through all
breakpoints in the array for a given module and look at the line and
column stored in the `SrcSpan`s. Similarly for columns and finding
breakpoints by name.
This logic previously lived within the `GHCi` application sources,
however, it is common to any GHC applications wanting to set
breakpoints, like the upcoming `ghc-debugger`.
This commit moves this logic for finding and setting breakpoints to the
GHC library so it can be used by both `ghci` and `ghc-debugger`.
-
bc0b9f73
by Rodrigo Mesquita at 2025-04-08T17:41:51-04:00
Refactor and move logic for identifier breakpoints
Breakpoints can be set on functions using syntax of the form
`[Module.]function`. The parsing, resolution (e.g. inferring implicit
module), and validation of this syntax for referring to functions was
tightly coupled with its GHCi use.
This commit extracts the general purpose bits of resolving this syntax
into `GHC.Runtime.Debugger.Breakpoints` so it can be further used by
other GHC applications and to improve the code structure of GHCi.
Moreover, a few utilities that do splitting and joining of identifiers
as strings were moved to `GHC.Runtime.Eval.Utils`, which also can be
used in the future to clean up `GHC.Runtime.Eval` a bit.
-
4f728d21
by Rodrigo Mesquita at 2025-04-08T17:41:51-04:00
debugger: derive Ord for BreakpointIds
-
5528771c
by Rodrigo Mesquita at 2025-04-08T17:41:51-04:00
debugger: Move context utils from GHCi to GHC
Moves `enclosingTickSpan`, `getCurrentBreakSpan`, and
`getCurrentBreakModule`, general utilities on the internal debugger
state, into the GHC library.
-
4871f543
by sheaf at 2025-04-08T17:42:43-04:00
Implicit quantification in type synonyms: add test
This adds a test for ticket #24090, which involves implicit
quantification in type synonyms.
The underlying issue was fixed in 0d4ee209dfe53e5074d786487f531dabc36d561c.
-
48917d3c
by sheaf at 2025-04-08T17:42:44-04:00
Turn on implicit-rhs-quantification by default
This flag was added to GHC 9.8, and will be removed in a future GHC
release. In preparation, this commit adds it to the default warning
flags.
-
629be068
by Rodrigo Mesquita at 2025-04-08T17:43:26-04:00
debugger: Add breakpoints to every Stmt
While single-stepping through a Haskell program we stop at every
breakpoint. However, we don't introduce breakpoints at every single
expression (e.g. single variables) because they would be too many and
uninteresting.
That said, in a do-block, it is expected that stepping over would break
at every line, even if it isn't particularly interesting (e.g. a single
arg like getArgs). Moreover, let-statements in do-blocks, despite only
being evaluated once needed, lead to surprising jumps while stepping
through because some have outermost (outside the let) breakpoints
while others don't.
This commit makes every statement in a do-block have a breakpoint.
This leads to predictable stepping through in a do-block.
Duplicate breakpoints in the same location are avoided using the
existing blacklist mechanism, which was missing a check in one relevant place.
Fixes #25932
-
99a3affd
by Matthew Pickering at 2025-04-08T17:44:08-04:00
driver: refactor: Split downsweep and MakeAction into separate modules.
This will facilitate using the downsweep functions in other parts of
the compiler than just --make mode.
Also, the GHC.Driver.Make module was huge. Now it's still huge but
slightly smaller!
-
ecfec4df
by sheaf at 2025-04-09T14:13:12-04:00
Store user-written qualification in the GhcRn AST
This commit ensures we store the original user-written module
qualification in the renamed AST. This allows us to take into account
the user-written qualification in error messages.
Fixes #25877
-
97c884e2
by sheaf at 2025-04-09T14:13:12-04:00
TcRnIllegalTermLevelUse: simpler error when possible
This commit makes GHC emit a simple error message in the case of an
illegal term-level use of a data constructor: we will try to report an
out-of-scope error instead of a "Illegal term level use" error, as the
latter might be a bit overwhelming for newcomers.
We do this when we have a data constructor import suggestion to provide
to the user. For example:
module M where { data A = A }
module N where
import M(A)
x = Bool
-- Illegal term-level use of Bool
y = A
-- Data constructor not in scope: A.
-- Perhaps add 'A' to the import list of 'M'.
This commit also revamps the "similar names" suggestion mechanism,
and in particular its treatment of name spaces. Now, which name spaces
we suggest is based solely on what we are looking for, and no longer on
the NameSpace of the Name we have. This is because, for illegal term-level
use errors, it doesn't make much sense to change the suggestions based
on the fact that we resolved to e.g. a type constructor/class; what
matters is what we were expecting to see in this position.
See GHC.Rename.Unbound.{suggestionIsRelevant,relevantNameSpace} as well
as the new constructors to GHC.Tc.Errors.Types.WhatLooking.
Fixes #23982
-
bff645ab
by Rodrigo Mesquita at 2025-04-09T14:13:57-04:00
driver: Split Session functions out of Main
This commit moves out functions that help in creating and validating a
GHC multi session from Main into the ghc library where they can be used by
other GHC applications.
Moreover, `Mode` processing and `checkOptions` linting were moved to
separate modules within the ghc-bin executable package.
In particular:
- Move `Mode` types and functions (referring to the mode GHC is running
on) to `ghc-bin:GHC.Driver.Session.Mode`
- Move `checkOptions` and aux functions, which validates GHC DynFlags
based on the mode, to `ghc-bin:GHC.Driver.Session.Lint`
- Moves `initMulti`, `initMake`, and aux functions, which initializes a make/multi-unit
session, into `ghc:GHC.Driver.Session.Units`.
-
501b015e
by Rodrigo Mesquita at 2025-04-09T14:13:57-04:00
docs: Improve haddock of ExecComplete
-
dea98988
by Andreas Klebinger at 2025-04-09T19:23:57-04:00
Avoid oversaturing constructor workers.
Constructor applications always need to take the exact number of
arguments. If we can't ensure that instead apply the constructor worker
like a regular function.
Fixes #23865
-
f1acdd2c
by sheaf at 2025-04-09T19:25:41-04:00
NamedDefaults: require the class to be standard
We now only default type variables if they only appear in constraints
of the form `C v`, where `C` is either a standard class or a class with
an in-scope default declaration.
This rectifies an oversight in the original implementation of the
NamedDefault extensions that was remarked in #25775; that implementation
allowed type variables to appear in unary constraints which had arbitrary
classes at the head.
See the rewritten Note [How type-class constraints are defaulted] for
details of the implementation.
Fixes #25775
Fixes #25778
-
5712e0d6
by Vladislav Zavialov at 2025-04-10T05:17:38+00:00
Retry type/class declarations and instances (#12088)
Retry type/class declarations and instances to account for non-lexical
dependencies arising from type/data family instances.
This patch improves the kind checker's ability to use type instances in kind
checking of other declarations in the same module.
* Key change: tcTyAndClassDecls now does multiple passes over the TyClGroups,
as long as it is able to make progress.
See the new Note [Retrying TyClGroups] in GHC.Tc.TyCl
* Supporting change: FVs of a TyClGroup are now recorded in its extension
field, namely XCTyClGroup.
See the new Note [Prepare TyClGroup FVs] in GHC.Rename.Module
* Instances are no longer inserted at the earliest positions where their FVs
are bound. This is a simplification.
See the new Note [Put instances at the end] in GHC.Rename.Module
* Automatic unpacking is now more predictable, but fewer fields get unpacked
by default. Use explicit {-# UNPACK #-} pragmas instead.
See the new Note [Flaky -funbox-strict-fields with type/data families]
For the wide range of newly accepted programs, consult the added test cases.
Fixed tickets:
#12088, #12239, #14668, #15561, #16410, #16448, #16693,
#19611, #20875, #21172, #22257, #25238, #25834
Metric Decrease:
T8095
-
bc73a78d
by sheaf at 2025-04-10T15:07:24-04:00
checkFamApp: don't be so eager to cycle break
As remarked in #25933, a pure refactoring of checkTyEqRhs in
ab77fc8c7adebd610aa0bd99d653f9a6cc78a374 inadvertently changed behaviour,
as it caused GHC to introduce cycle-breaker variables in some
unnecessary circumstances.
This commit refactors 'GHC.Tc.Utils.Unify.checkFamApp' in a way that
should restore the old behaviour, so that, when possible, we first
recur into the arguments and only introduce a cycle breaker if this
recursion fails (e.g. due to an occurs check failure).
Fixes #25933
-
3acd8182
by Andreas Klebinger at 2025-04-10T22:32:12-04:00
Expand docs for RTS flag `-M`.
The behaviour of how/when exceptions are raised was not really covered
in the docs.
-
026c1a39
by Adam Sandberg Ericsson at 2025-04-10T22:32:56-04:00
add cases for more SchedulerStatus codes in rts_checkSchedStatus
-
5977c6a1
by sheaf at 2025-04-10T22:33:46-04:00
Squash warnings in GHC.Runtime.Heap.Inspect
There were incomplete record selector warnings in GHC.Runtime.Heap.Inspect
due to the use of the partial 'dataArgs' record selector. This is fixed
by passing the fields to the 'extractSubTerms' function directly,
rather than passing a value of the parent data type.
-
6a3e38f5
by Andreas Klebinger at 2025-04-11T15:13:53-04:00
hadrian: Make ghcWithInterpreter the universal source of truth about availability of the interpreter
We were doing some ad-hoc checks in different places in hadrian to
determine whether we supported the interprter or not. Now this check if
confined to one function, `ghcWithInterpreter`, and all the places which
use this information consult `ghcWithInterpreter` to determine what to
do.
Fixes #25533.
-
207de6f1
by Matthew Pickering at 2025-04-11T15:14:37-04:00
testsuite: Fix running TH tests with profiled dynamic compiler
Previously, I had failed to update the ghc_th_way_flags logic for the
profiled dynamic compiler.
In addition to this `ghc_dynamic` was incorrectly set for profiled
dynamic compiler.
I also updated MultiLayerModulesTH_OneShot test to work for any compiler
linkage rather than just dynamic.
Fixes #25947
-------------------------
Metric Decrease:
MultiLayerModulesTH_Make
-------------------------
-
5455f2b9
by Matthew Pickering at 2025-04-12T08:31:36-04:00
driver: Add support for "Fixed" nodes in the ModuleGraph
A fixed node in the module graph is one which we presume is already
built. It's therefore up to the user to make sure that the interface
file and any relevant artifacts are available for a fixed node.
Fixed/Compile nodes are represented by the ModuleNodeInfo type, which
abstracts the common parts of Fixed/Compile nodes with accessor
functions of type `ModuleNodeInfo -> ...`.
Fixed nodes can only depend on other fixed nodes. This invariant can be
checked by the function `checkModuleGraph` or `mkModuleGraphChecked`.
--make mode is modified to work with fixed mode. In order to "compile" a
fixed node, the artifacts are just loaded into the HomePackageTable.
Currently nothing in the compiler will produce Fixed nodes but this is
tested with the FixedNodes GHC API test.
In subsequent patches we are going to remove the ExternalModuleGraph and
use Fixed nodes for modules in the module graph in oneshot mode.
Fixes #25920
-
ad64d5c2
by Cheng Shao at 2025-04-12T08:32:19-04:00
ci: remove manual case of ghc-wasm-meta downstream testing jobs
This patch removes the manual case of ghc-wasm-meta downstream testing
jobs; now the only way of including them in the pipeline and running
them is via the test-wasm label.
The reason of the removal is it proves to be problematic for MRs with
only the wasm label; the wasm job would succeed, then the pipeline
status would be waiting for manual action instead of succeeding. There
needs to be separate jobs for the label-triggered and manual-triggered
cases, but I don't think it's worth that extra complexity, the
label-triggered case is already sufficient.
-
b34890c7
by Vladislav Zavialov at 2025-04-13T01:08:21+03:00
Fix EmptyCase panic in tcMatches (#25960)
Due to faulty reasoning in Note [Pattern types for EmptyCase],
tcMatches was too keen to panic.
* Old (incorrect) assumption: pat_tys is a singleton list.
This does not hold when \case{} is checked against a function type
preceded by invisible forall. See the new T25960 test case.
* New (hopefully correct) assumption: vis_pat_tys is a singleton list.
This should follow from:
checkArgCounts :: MatchGroup GhcRn ... -> TcM VisArity
checkArgCounts (MG { mg_alts = L _ [] })
= return 1
...
-
84806ebc
by Vladislav Zavialov at 2025-04-13T11:40:08-04:00
Remove unused type: TokenLocation
-
05eb50df
by Vladislav Zavialov at 2025-04-13T19:16:38-04:00
Register EpToken in Parser.PostProcess.Haddock (#22558)
This change allows us to reject more badly placed Haddock comments.
Examples:
module
-- | Bad comment for the module
T17544_kw where
data Foo -- | Bad comment for MkFoo
where MkFoo :: Foo
newtype Bar -- | Bad comment for MkBar
where MkBar :: () -> Bar
class Cls a
-- | Bad comment for clsmethod
where
clsmethod :: a
-
01944e5e
by Vladislav Zavialov at 2025-04-13T19:17:21-04:00
Reject puns in T2T (#24153)
This patch implements pun detection in T2T. Consider:
x = 42
f, g :: forall a -> ...
f (type x) = g x
In accordance with the specification, the `g x` function call is renamed
as a term, so `x` refers to the top-level binding `x = 42`, not to the
type variable binding `type x` as one might expect.
This is somewhat counterintuitive because `g` expects a type argument.
Forbidding puns in T2T allows us to produce a helpful error message:
Test.hs:5:16: error: [GHC-09591]
Illegal punned variable occurrence in a required type argument.
The name ‘x’ could refer to:
‘x’ defined at Test.hs:3:1
‘x’ bound at Test.hs:5:9
This commit is a follow up to 0dfb1fa799af254c8a1e1045fc3996af2d57a613
where checking for puns was left as future work.
-
cc580552
by Vladislav Zavialov at 2025-04-13T19:18:02-04:00
Additional test cases for #12088, #13790
Extract more test cases from ticket discussions, including multi-module
examples. Follow up to 5712e0d646f611dfbfedfd7ef6dff3a18c016edb
-
d47bf776
by Matthew Pickering at 2025-04-14T16:44:41+01:00
driver: Use ModuleGraph for oneshot and --make mode
This patch uses the `hsc_mod_graph` field for both oneshot and --make
mode. Therefore, if part of the compiler requires usage of the module
graph, you do so in a uniform way for the two different modes.
The `ModuleGraph` describes the relationship between the modules in the
home package and units in external packages. The `ModuleGraph` can be
queried when information about the transitive closure of a package is
needed. For example, the primary use of the ModuleGraph from within the
compiler is in the loader, which needs to know the transitive closure of
a module so it can load all the relevant objects for evaluation.
In --make mode, downsweep computes the ModuleGraph before any
compilation starts.
In oneshot mode, a thunk is created at the start of compilation, which
when forced will compute the module graph beneath the current module.
The thunk is only forced at the moment when the user uses Template
Haskell.
Finally, there are some situations where we need to discover what
dependencies to load but haven't loaded a module graph at all. In this
case, there is a fallback which computes the transitive closure on the
fly and doesn't cache the result. Presumably if you are going to call
getLinkDeps a lot, you would compute the right ModuleGraph before you
started.
Importantly, this removes the ExternalModuleGraph abstraction. This was quite
awkward to work with since it stored information about the home package
inside the EPS.
This patch will also be very useful when implementing explicit level
imports, which requires more significant use of the module graph in
order to determine which level instances are available at.
Towards #25795
-------------------------
Metric Decrease:
MultiLayerModulesTH_Make
MultiLayerModulesTH_OneShot
-------------------------
-
395e0ad1
by sheaf at 2025-04-16T12:33:26-04:00
base: remove .Internal modules (e.g. GHC.TypeLits)
This commit removes the following internal modules from base,
as per CLC proposal 217:
- GHC.TypeNats.Internal
- GHC.TypeLits.Internal
- GHC.ExecutionStack.Internal
Fixes #25007
-
e0f3ff11
by Patrick at 2025-04-17T04:31:12-04:00
Refactor Handling of Multiple Default Declarations
Fixes: #25912, #25914, #25934
Previously, GHC discarded all loaded defaults (tcg_default) when local
defaults were encountered during typechecking. According to the
exportable-named-default proposal (sections 2.4.2 and 2.4.3), local
defaults should be merged into tcg_default, retaining any defaults
already present while overriding where necessary.
Key Changes:
* Introduce DefaultProvenance to track the origin of default declarations
(local, imported, or built-in), replacing the original cd_module
in ClassDefaults with cd_provenance :: DefaultProvenance.
* Rename tcDefaults to tcDefaultDecls, limiting its responsibility to only
converting renamed class defaults into ClassDefaults.
* Add extendDefaultEnvWithLocalDefaults to merge local defaults into the
environment, with proper duplication checks:
- Duplicate local defaults for a class trigger an error.
- Local defaults override imported or built-in defaults.
* Update and add related notes: Note [Builtin class defaults],
Note [DefaultProvenance].
* Add regression tests: T25912, T25914, T25934.
Thanks sam and simon for the help on this patch.
Co-authored-by: sheaf <sam.derbyshire@gmail.com>
-
386f1854
by Teo Camarasu at 2025-04-17T04:31:55-04:00
template-haskell: Remove `addrToByteArrayName` and `addrToByteArray`
These were part of the implementation of the `Lift ByteArray` instance and were errornously exported because this module lacked an explicit export list. They have no usages on Hackage.
Resolves #24782
-
b96e2f77
by Sylvain Henry at 2025-04-18T20:46:33-04:00
RTS: remove target info and fix host info (#24058)
The RTS isn't a compiler, hence it doesn't have a target and we remove
the reported target info displayed by "+RTS --info". We also fix the
host info displayed by "+RTS --info": the host of the RTS is the
RTS-building compiler's target, not the compiler's host (wrong when
doing cross-compilation).
-
6d9965f4
by Sylvain Henry at 2025-04-18T20:46:33-04:00
RTS: remove build info
As per the discussion in !13967, there is no reason to tag the RTS with
information about the build platform.
-
d52e9b3f
by Vladislav Zavialov at 2025-04-18T20:47:15-04:00
Diagnostics: remove the KindMismatch constructor (#25957)
The KindMismatch constructor was only used as an intermediate
representation in pretty-printing.
Its removal addresses a problem detected by the "codes" test case:
[GHC-89223] is untested (constructor = KindMismatch)
In a concious deviation from the usual procedure, the error code
GHC-89223 is removed entirely rather than marked as Outdated.
The reason is that it never was user-facing in the first place.
-
e2f2f9d0
by Vladislav Zavialov at 2025-04-20T10:53:39-04:00
Add name for -Wunusable-unpack-pragmas
This warning had no name or flag and was triggered unconditionally.
Now it is part of -Wdefault.
In GHC.Tc.TyCl.tcTyClGroupsPass's strict mode, we now have to
force-enable this warning to ensure that detection of flawed groups
continues to work even if the user disables the warning with the
-Wno-unusable-unpack-pragmas option. Test case: T3990c
Also, the misnamed BackpackUnpackAbstractType is now called
UnusableUnpackPragma.
-
6caa6508
by Adam Gundry at 2025-04-20T10:54:22-04:00
Fix specialisation of incoherent instances (fixes #25883)
GHC normally assumes that class constraints are canonical, meaning that
the specialiser is allowed to replace one dictionary argument with another
provided that they have the same type. The `-fno-specialise-incoherents`
flag alters INCOHERENT instance definitions so that they will prevent
specialisation in some cases, by inserting `nospec`.
This commit fixes a bug in 7124e4ad76d98f1fc246ada4fd7bf64413ff2f2e, which
treated some INCOHERENT instance matches as if `-fno-specialise-incoherents`
was in effect, thereby unnecessarily preventing specialisation. In addition
it updates the relevant `Note [Rules for instance lookup]` and adds a new
`Note [Canonicity for incoherent matches]`.
-
0426fd6c
by Adam Gundry at 2025-04-20T10:54:23-04:00
Add regression test for #23429
-
eec96527
by Adam Gundry at 2025-04-20T10:54:23-04:00
user's guide: update specification of overlapping/incoherent instances
The description of the instance resolution algorithm in the user's
guide was slightly out of date, because it mentioned in-scope given
constraints only at the end, whereas the implementation checks for
their presence before any of the other steps.
This also adds a warning to the user's guide about the impact of
incoherent instances on specialisation, and more clearly documents
some of the other effects of `-XIncoherentInstances`.
-
a00eeaec
by Matthew Craven at 2025-04-20T10:55:03-04:00
Fix bytecode generation for `tagToEnum# <LITERAL>`
Fixes #25975.
-
2e204269
by Andreas Klebinger at 2025-04-22T12:20:41+02:00
Simplifier: Constant fold invald tagToEnum# calls to bottom expr.
When applying tagToEnum# to a out-of-range value it's best to simply
constant fold it to a bottom expression. That potentially allows more
dead code elimination and makes debugging easier.
Fixes #25976
-
7250fc0c
by Matthew Pickering at 2025-04-22T16:24:04-04:00
Move -fno-code note into Downsweep module
This note was left behind when all the code which referred to it was
moved into the GHC.Driver.Downsweep module
-
d2dc89b4
by Matthew Pickering at 2025-04-22T16:24:04-04:00
Apply editing notes to Note [-fno-code mode] suggested by sheaf
These notes were suggested in https://gitlab.haskell.org/ghc/ghc/-/merge_requests/14241
-
91564daf
by Matthew Pickering at 2025-04-24T00:29:02-04:00
ghci: Use loadInterfaceForModule rather than loadSrcInterface in mkTopLevEnv
loadSrcInterface takes a user given `ModuleName` and resolves it to the
module which needs to be loaded (taking into account module
renaming/visibility etc).
loadInterfaceForModule takes a specific module and loads it.
The modules in `ImpDeclSpec` have already been resolved to the actual
module to get the information from during renaming. Therefore we just
need to fetch the precise interface from disk (and not attempt to rename
it again).
Fixes #25951
-
2e0c07ab
by Simon Peyton Jones at 2025-04-24T00:29:43-04:00
Test for #23298
-
0eef99b0
by Sven Tennie at 2025-04-24T07:34:36-04:00
RV64: Introduce J instruction (non-local jumps) and don't deallocate stack slots for J_TBL (#25738)
J_TBL result in local jumps, there should not deallocate stack slots
(see Note [extra spill slots].)
J is for non-local jumps, these may need to deallocate stack slots.
-
1bd3d13e
by fendor at 2025-04-24T07:35:17-04:00
Add `UnitId` to `EvalBreakpoint`
The `EvalBreakpoint` is used to communicate that a breakpoint was
encountered during code evaluation.
This `EvalBreakpoint` needs to be converted to an `InternalBreakpointId`
which stores a `Module` to uniquely find the correct `Module` in the
Home Package Table.
The `EvalBreakpoint` used to store only a `ModuleName` which is then
converted to a `Module` based on the currently active home unit.
This is incorrect in the face of multiple home units, the break point
could be in an entirely other home unit!
To fix this, we additionally store the `UnitId` of the `Module` in
`EvalBreakpoint` to later reconstruct the correct `Module`
All of the changes are the consequence of extending `EvalBreakpoint`
with the additional `ShortByteString` of the `UnitId`.
For performance reasons, we store the `ShortByteString` backing the
`UnitId` directly, avoiding marshalling overhead.
-
fe6ed8d9
by Sylvain Henry at 2025-04-24T18:04:12-04:00
Doc: add doc for JS interruptible calling convention (#24444)
-
6111c5e4
by Ben Gamari at 2025-04-24T18:04:53-04:00
compiler: Ensure that Panic.Plain.assertPanic' provides callstack
In 36cddd2ce1a3bc62ea8a1307d8bc6006d54109cf @alt-romes removed CallStack
output from `GHC.Utils.Panic.Plain.assertPanic'`. While this output is
redundant due to the exception backtrace proposal, we may be
bootstrapping with a compiler which does not yet include this machinery.
Reintroduce the output for now.
Fixes #25898.
-
217caad1
by Matthew Pickering at 2025-04-25T18:58:42+01:00
Implement Explicit Level Imports for Template Haskell
This commit introduces the `ExplicitLevelImports` and
`ImplicitStagePersistence` language extensions as proposed in GHC
Proposal #682.
Key Features
------------
- `ExplicitLevelImports` adds two new import modifiers - `splice` and
`quote` - allowing precise control over the level at which imported
identifiers are available
- `ImplicitStagePersistence` (enabled by default) preserves existing
path-based cross-stage persistence behavior
- `NoImplicitStagePersistence` disables implicit cross-stage
persistence, requiring explicit level imports
Benefits
--------
- Improved compilation performance by reducing unnecessary code generation
- Enhanced IDE experience with faster feedback in `-fno-code` mode
- Better dependency tracking by distinguishing compile-time and runtime dependencies
- Foundation for future cross-compilation improvements
This implementation enables the separation of modules needed at
compile-time from those needed at runtime, allowing for more efficient
compilation pipelines and clearer code organization in projects using
Template Haskell.
Implementation Notes
--------------------
The level which a name is availble at is stored in the 'GRE', in the normal
GlobalRdrEnv. The function `greLevels` returns the levels which a specific GRE
is imported at. The level information for a 'Name' is computed by `getCurrentAndBindLevel`.
The level validity is checked by `checkCrossLevelLifting`.
Instances are checked by `checkWellLevelledDFun`, which computes the level an
instance by calling `checkWellLevelledInstanceWhat`, which sees what is
available at by looking at the module graph.
Modifications to downsweep
--------------------------
Code generation is now only enabled for modules which are needed at
compile time.
See the Note [-fno-code mode] for more information.
Uniform error messages for level errors
---------------------------------------
All error messages to do with levels are now reported uniformly using
the `TcRnBadlyStaged` constructor.
Error messages are uniformly reported in terms of levels.
0 - top-level
1 - quote level
-1 - splice level
The only level hard-coded into the compiler is the top-level in
GHC.Types.ThLevelIndex.topLevelIndex.
Uniformly refer to levels and stages
------------------------------------
There was much confusion about levels vs stages in the compiler.
A level is a semantic concept, used by the typechecker to ensure a
program can be evaluated in a well-staged manner.
A stage is an operational construct, program evaluation proceeds in
stages.
Deprecate -Wbadly-staged-types
------------------------------
`-Wbadly-staged-types` is deprecated in favour of `-Wbadly-levelled-types`.
Lift derivation changed
-----------------------
Derived lift instances will now not generate code with expression
quotations.
Before:
```
data A = A Int deriving Lift
=>
lift (A x) = [| A $(lift x) |]
```
After:
```
lift (A x) = conE 'A `appE` (lift x)
```
This is because if you attempt to derive `Lift` in a module where
`NoImplicitStagePersistence` is enabled, you would get an infinite loop
where a constructor was attempted to be persisted using the instance you
are currently defining.
GHC API Changes
---------------
The ModuleGraph now contains additional information about the type of
the edges (normal, quote or splice) between modules. This is abstracted
using the `ModuleGraphEdge` data type.
Fixes #25828
-------------------------
Metric Increase:
MultiLayerModulesTH_Make
-------------------------
-
7641a74a
by Simon Peyton Jones at 2025-04-26T22:05:19-04:00
Get a decent MatchContext for pattern synonym bindings
In particular when we have a pattern binding
K p1 .. pn = rhs
where K is a pattern synonym. (It might be nested.)
This small MR fixes #25995. It's a tiny fix, to an error message,
removing an always-dubious `unkSkol`.
The bug report was in the context of horde-ad, a big program,
and I didn't manage to make a small repro case quickly. I decided
not to bother further.
-
ce616f49
by Simon Peyton Jones at 2025-04-27T21:10:25+01:00
Fix infelicities in the Specialiser
On the way to #23109 (unary classes) I discovered some infelicities
(or maybe tiny bugs, I forget) in the type-class specialiser.
I also tripped over #25965, an outright bug in the rule matcher
Specifically:
* Refactor: I enhanced `wantCallsFor`, whih previously always said
`True`, to discard calls of class-ops, data constructors etc. This is
a bit more efficient; and it means we don't need to worry about
filtering them out later.
* Fix: I tidied up some tricky logic that eliminated redundant
specialisations. It wasn't working correctly. See the expanded
Note [Specialisations already covered], and
(MP3) in Note [Specialising polymorphic dictionaries].
See also the new top-level `alreadyCovered`
function, which now goes via `GHC.Core.Rules.ruleLhsIsMoreSpecific`
I also added a useful Note [The (CI-KEY) invariant]
* Fix #25965: fixed a tricky bug in the `go_fam_fam` in
`GHC.Core.Unify.uVarOrFam`, which allows matching to succeed
without binding all type varibles.
I enhanced Note [Apartness and type families] some more
* #25703. This ticket "just works" with -fpolymorphic-specialisation;
but I was surprised that it worked! In this MR I added documentation
to Note [Interesting dictionary arguments] to explain; and tests to
ensure it stays fixed.
-
22d11fa8
by Simon Peyton Jones at 2025-04-28T18:05:19-04:00
Track rewriter sets more accurately in constraint solving
The key change, which fixed #25440, is to call `recordRewriter` in
GHC.Tc.Solver.Rewrite.rewrite_exact_fam_app. This missing call meant
that we were secretly rewriting a Wanted with a Wanted, but not really
noticing; and that led to a very bad error message, as you can see
in the ticket.
But of course that led me into rabbit hole of other refactoring around
the RewriteSet code:
* Improve Notes [Wanteds rewrite Wanteds]
* Zonk the RewriterSet in `zonkCtEvidence` rather than only in GHC.Tc.Errors.
This is tidier anyway (e.g. de-clutters debug output), and helps with the
next point.
* In GHC.Tc.Solver.Equality.inertsCanDischarge, don't replace a constraint
with no rewriters with an equal constraint that has many. See
See (CE4) in Note [Combining equalities]
* Move zonkRewriterSet and friends from GHC.Tc.Zonk.Type into
GHC.Tc.Zonk.TcType, where they properly belong.
A handful of tests get better error messages.
For some reason T24984 gets 12% less compiler allocation -- good
Metric Decrease:
T24984
-
6467d61e
by Brandon Chinn at 2025-04-29T18:36:03-04:00
Fix lexing "\^\" (#25937)
This broke in the refactor in !13128, where the old code parsed escape
codes and collapsed string gaps at the same time, but the new code
collapsed gaps first, then resolved escape codes. The new code used a
naive heuristic to skip escaped backslashes, but didn't account for
"\^\".
-
99868a86
by Jens Petersen at 2025-04-29T18:36:44-04:00
hadrian: default selftest to disabled
-
aba2a4a5
by Zubin Duggal at 2025-04-30T06:35:59-04:00
get-win32-tarballs.py: List tarball files to be downloaded if we cannot find them
Fixes #25929
-
d99a617b
by Ben Gamari at 2025-04-30T06:36:40-04:00
Move Data ModuleName instance to Language.Haskell.Syntax.Module.Name
Fixes #25968.
-
9995c2b7
by Serge S. Gulin at 2025-05-04T17:13:36+03:00
Support for ARM64 Windows (LLVM-enabled) (fixes #24603)
1. Add Windows AArch64 cross-compilation support via CI jobs
Introduce new CI configurations for cross-compiling to Windows ARM64 using Debian12Wine, FEX, and MSYS2.
Configure toolchain variables for LLVM MinGW and Wine emulation in CI pipelines.
2. Adjust compiler and RTS for AArch64 Windows compatibility
Reserve register `x18` on Windows and Darwin platforms in AArch64 codegen.
Handle Windows-specific relocations and data sections in AArch64 assembler.
Update PEi386 linker to recognize ARM64 binaries and support exception handling.
Adjust LLVM target definitions and data layouts for new architectures.
Update `ghc-toolchain` and build scripts to handle `TablesNextToCode` on Windows ARM64.
3. Enhance CI scripts and stability
Modify `ci.sh` to handle mingw cross-targets, fixing GHC executable paths and test execution.
Use `diff -w` in tests to ignore whitespace differences, improving cross-platform consistency.
4. Refactor and clean up code
Remove redundant imports in hello.hs test.
Improve error messages and checks for unsupported configurations in the driver.
Add `EXDEV` error code to `errno.js`.
Add async/sync flags to IO logs at `base.js`.
Improve POSIX compatibility for file close at `base.js`: decrease indeterminism for mixed cases of async and sync code.
5. Update dependencies: `Cabal`, `Win32`, `directory`, `process`, `haskeline`, and `unix`.
submodule
Co-authored-by: Cheng Shao <terrorjack@type.dance>
Co-authored-by: Dmitrii Egorov <egorov.d.i@icloud.com>
Co-authored-by: Andrei Borzenkov <root@sandwitch.dev>
-
50fa8165
by Javran Cheng at 2025-05-05T05:55:39-04:00
Suppress unused do-binding if discarded variable is Any or ZonkAny.
Consider example (#25895):
> do { forever (return ()); blah }
where `forever :: forall a b. IO a -> IO b`.
Nothing constrains `b`, so it will be instantiates with `Any` or
`ZonkAny`.
But we certainly don't want to complain about a discarded do-binding.
Fixes #25895
-
e46c6b18
by Rodrigo Mesquita at 2025-05-06T09:01:57-04:00
Refactor mkTopLevImportedEnv out of mkTopLevEnv
This makes the code clearer and allows the top-level import context to
be fetched directly from the HomeModInfo through the API (e.g. useful
for the debugger).
-
0ce0d263
by Rodrigo Mesquita at 2025-05-06T09:01:57-04:00
Export sizeOccEnv from GHC.Types.Name.Occurrence
Counts the number of OccNames in an OccEnv
-
165f98d8
by Simon Peyton Jones at 2025-05-06T09:02:39-04:00
Fix a bad untouchability bug im simplifyInfer
This patch addresses #26004. The root cause was that simplifyInfer
was willing to unify variables "far out". The fix, in
runTcSWithEvBinds', is to initialise the inert set given-eq level with
the current level. See
(TGE6) in Note [Tracking Given equalities]
in GHC.Tc.Solver.InertSet
Two loosely related refactors:
* Refactored approximateWCX to return just the free type
variables of the un-quantified constraints. That avoids duplication
of work (these free vars are needed in simplifyInfer) and makes it
clearer that the constraints themselves are irrelevant.
* A little local refactor of TcSMode, which reduces the number of
parameters to runTcSWithEvBinds
-
6e67fa08
by Ben Gamari at 2025-05-08T06:21:21-04:00
llvmGen: Fix built-in variable predicate
Previously the predicate to identify LLVM builtin global variables was
checking for `$llvm` rather than `@llvm` as it should.
-
a9d0a22c
by Ben Gamari at 2025-05-08T06:21:22-04:00
llvmGen: Fix linkage of built-in arrays
LLVM now insists that built-in arrays use Appending linkage, not
Internal.
Fixes #25769.
-
9c6d2b1b
by sheaf at 2025-05-08T06:22:11-04:00
Use mkTrAppChecked in ds_ev_typeable
This change avoids violating the invariant of mkTrApp according to which
the argument should not be a fully saturated function type.
This ensures we don't return false negatives for type equality
involving function types.
Fixes #25998
-
75cadf81
by Ryan Hendrickson at 2025-05-08T06:22:55-04:00
haddock: Preserve indentation in multiline examples
Intended for use with :{ :}, but doesn't look for those characters. Any
consecutive lines with birdtracks will only have initial whitespace
stripped up to the column of the first line.
-
fee9b351
by Cheng Shao at 2025-05-08T06:23:36-04:00
ci: re-enable chrome for wasm ghci browser tests
Currently only firefox is enabled for wasm ghci browser tests, for
some reason testing with chrome works on my machine but gets stuck on
gitlab instance runners. This patch re-enables testing with chrome by
passing `--no-sandbox`, since chrome sandboxing doesn't work in
containers without `--cap-add=SYS_ADMIN`.
-
282df905
by Vladislav Zavialov at 2025-05-09T03:18:25-04:00
Take subordinate 'type' specifiers into account
This patch fixes multiple bugs (#22581, #25983, #25984, #25991)
in name resolution of subordinate import lists.
Bug #22581
----------
In subordinate import lists, the use of the `type` namespace specifier
used to be ignored. For example, this import statement was incorrectly
accepted:
import Prelude (Bool(type True))
Now it results in an error message:
<interactive>:2:17: error: [GHC-51433]
In the import of ‘Prelude’:
a data type called ‘Bool’ is exported,
but its subordinate item ‘True’ is not in the type namespace.
Bug #25983
----------
In subordinate import lists within a `hiding` clause, non-existent
items led to a poor warning message with -Wdodgy-imports. Consider:
import Prelude hiding (Bool(X))
The warning message for this import statement used to misreport the
cause of the problem:
<interactive>:3:24: warning: [GHC-56449] [-Wdodgy-imports]
In the import of ‘Prelude’:
an item called ‘Bool’ is exported, but it is a type.
Now the warning message is correct:
<interactive>:2:24: warning: [GHC-10237] [-Wdodgy-imports]
In the import of ‘Prelude’:
a data type called ‘Bool’ is exported, but it does not export
any constructors or record fields called ‘X’.
Bug #25984
----------
In subordinate import lists within a `hiding` clause, non-existent
items resulted in the entire import declaration being discarded.
For example, this program was incorrectly accepted:
import Prelude hiding (Bool(True,X))
t = True
Now it results in an error message:
<interactive>:2:5: error: [GHC-88464]
Data constructor not in scope: True
Bug #25991
----------
In subordinate import lists, it was not possible to refer to a class
method if there was an associated type of the same name:
module M_helper where
class C a b where
type a # b
(#) :: a -> b -> ()
module M where
import M_helper (C((#)))
This import declaration failed with:
M.hs:2:28: error: [GHC-10237]
In the import of ‘M_helper’:
an item called ‘C’ is exported, but it does not export any children
(constructors, class methods or field names) called ‘#’.
Now it is accepted.
Summary
-------
The changes required to fix these bugs are almost entirely confined to
GHC.Rename.Names. Other than that, there is a new error constructor
BadImportNonTypeSubordinates with error code [GHC-51433].
Test cases:
T22581a T22581b T22581c T22581d
T25983a T25983b T25983c T25983d T25983e T25983f T25983g
T25984a T25984b
T25991a T25991b1 T25991b2
-
51b0ce8f
by Simon Peyton Jones at 2025-05-09T03:19:07-04:00
Slighty improve `dropMisleading`
Fix #26105, by upgrading the (horrible, hacky) `dropMisleading`
function.
This fix makes things a bit better but does not cure the underlying
problem.
-
7b2d1e6d
by Simon Peyton Jones at 2025-05-11T03:24:47-04:00
Refine `noGivenNewtypeReprEqs` to account for quantified constraints
This little MR fixes #26020. We are on the edge of completeness
for newtype equalities (that doesn't change) but this MR makes GHC
a bit more consistent -- and fixes the bug reported.
-
eaa8093b
by Cheng Shao at 2025-05-11T03:25:28-04:00
wasm: mark freeJSVal as INLINE
This patch marks `freeJSVal` as `INLINE` for the wasm backend. I
noticed that the `freeJSVal` invocations are not inlined when
inspecting STG/Cmm dumps of downstream libraries that use release
build of the wasm backend. The performance benefit of inlining here is
very modest, but so is the cost anyway; if you are using `freeJSVal`
at all then you care about every potential chance to improve
performance :)
-
eac196df
by Cheng Shao at 2025-05-11T03:25:28-04:00
wasm: add zero length fast path for fromJSString
This patch adds a zero length fast path for `fromJSString`; when
marshaling a zero-length `JSString` we don't need to allocate an empty
`ByteArray#` at all.
-
652cba7e
by Peng Fan at 2025-05-14T04:24:35-04:00
Add LoongArch NCG support
Not supported before.
-
c01f4374
by Lin Runze at 2025-05-14T04:24:35-04:00
ci: Add LoongArch64 cross-compile CI for testing
-
ce6cf240
by Ben Gamari at 2025-05-14T04:25:18-04:00
rts/linker: Don't fail due to RTLD_NOW
In !12264 we started using the NativeObj machinery introduced some time
ago for loading of shared objects. One of the side-effects of this
change is shared objects are now loaded eagerly (i.e. with `RTLD_NOW`).
This is needed by NativeObj to ensure full visibility of the mappings of
the loaded object, which is in turn needed for safe shared object
unloading.
Unfortunately, this change subtly regressed, causing compilation
failures in some programs. Specifically, shared objects which refer to
undefined symbols (e.g. which may be usually provided by either the
executable image or libraries loaded via `dlopen`) will fail to load
with eager binding. This is problematic as GHC loads all package
dependencies while, e.g., evaluating TemplateHaskell splices. This
results in compilation failures in programs depending upon (but not
using at compile-time) packages with undefined symbol references.
To mitigate this NativeObj now first attempts to load an object via
eager binding, reverting to lazy binding (and disabling unloading) on
failure.
See Note [Don't fail due to RTLD_NOW].
Fixes #25943.
-
88ee8bb5
by Sylvain Henry at 2025-05-14T04:26:15-04:00
Deprecate GHC.JS.Prim.Internal.Build (#23432)
Deprecated as per CLC proposal 329 (https://github.com/haskell/core-libraries-committee/issues/329)
-
b4ed465b
by Cheng Shao at 2025-05-14T04:26:57-04:00
libffi: update to 3.4.8
Bumps libffi submodule.
-
a3e71296
by Matthew Pickering at 2025-05-14T04:27:38-04:00
Remove leftover trace
-
2d0ecdc6
by Cheng Shao at 2025-05-14T04:28:19-04:00
Revert "ci: re-enable chrome for wasm ghci browser tests"
This reverts commit fee9b351fa5a35d5778d1252789eacaaf5663ae8.
Unfortunately the chrome test jobs may still timeout on certain
runners (e.g. OpenCape) for unknown reasons.
-
3b3a5dec
by Ben Gamari at 2025-05-15T16:10:01-04:00
Don't emit unprintable characters when printing Uniques
When faced with an unprintable tag we now instead print the codepoint
number.
Fixes #25989.
(cherry picked from commit e832b1fadee66e8d6dd7b019368974756f8f8c46)
-
e1ef8974
by Mike Pilgrem at 2025-05-16T16:09:14-04:00
Translate iff in Haddock documentation into everyday English
-
fd64667d
by Vladislav Zavialov at 2025-05-20T03:25:08-04:00
Allow the 'data' keyword in import/export lists (#25899)
This patch introduces the 'data' namespace specifier in import and
export lists. The intended use is to import data constructors without
their parent type constructors, e.g.
import Data.Proxy as D (data Proxy)
type DP = D.Proxy -- promoted data constructor
Additionally, it is possible to use 'data' to explicitly qualify any
data constructors or terms, incl. operators and field selectors
import Prelude (Semigroup(data (<>)))
import Data.Function (data (&))
import Data.Monoid (data Dual, data getDual)
x = Dual "Hello" <> Dual "World" & getDual
The implementation mostly builds on top of the existing logic for the
'type' and 'pattern' namespace specifiers, plus there are a few tweaks
to how we generate suggestions in error messages.
-
acc86753
by Ben Gamari at 2025-05-20T03:25:51-04:00
compiler: Use field selectors when creating BCOs
This makes it easier to grep for these fields.
-
60a55fd7
by Ben Gamari at 2025-05-20T03:25:51-04:00
compiler: Clarify BCO size
Previously the semantics and size of StgBCO was a bit unclear.
Specifically, the `size` field was documented to contain the size of the
bitmap whereas it was actually the size of the closure *and* bitmap.
Additionally, it was not as clear as it could be that the bitmap was a
full StgLargeBitmap with its own `size` field.
-
ac9fb269
by Simon Peyton Jones at 2025-05-20T09:19:04-04:00
Track rewriter sets more accurately in constraint solving
This MR addresses #26003, by refactoring the arcane
intricacies of Note [Equalities with incompatible kinds].
NB: now retitled to
Note [Equalities with heterogeneous kinds].
and the main Note for this MR.
In particular:
* Abandon invariant (COERCION-HOLE) in Note [Unification preconditions] in
GHC.Tc.Utils.Unify.
* Abandon invariant (TyEq:CH)) in Note [Canonical equalities] in
GHC.Tc.Types.Constraint.
* Instead: add invariant (REWRITERS) to Note [Unification preconditions]:
unify only if the constraint has an empty rewriter set.
Implementation:
* In canEqCanLHSFinish_try_unification, skip trying unification if there is a
non-empty rewriter set.
* To do this, make sure the rewriter set is zonked; do so in selectNextWorkItem,
which also deals with prioritisation.
* When a coercion hole is filled, kick out inert equalities that have that hole
as a rewriter. It might now be unlocked and available to unify.
* Remove the ad-hoc `ch_hetero_kind` field of `CoercionHole`.
* In `selectNextWorkItem`, priorities equalities withan empty rewriter set.
* Defaulting: see (DE6) in Note [Defaulting equalities]
and Note [Limited defaulting in the ambiguity check]
* Concreteness checks: there is some extra faff to try to get decent
error messages when the FRR (representation-polymorphism) checks
fail. In partiular, add a "When unifying..." explanation when the
representation-polymorphism check arose from another constraint.
-
86406f48
by Cheng Shao at 2025-05-20T09:19:47-04:00
rts: fix rts_clearMemory logic when sanity checks are enabled
This commit fixes an RTS assertion failure when invoking
rts_clearMemory with +RTS -DS. -DS implies -DZ which asserts that free
blocks contain 0xaa as the designated garbage value. Also adds the
sanity way to rts_clearMemory test to prevent future regression.
Closes #26011.
ChatGPT Codex automatically diagnosed the issue and proposed the
initial patch in a single shot, given a GHC checkout and the following
prompt:
---
Someone is reporting the following error when attempting to use `rts_clearMemory` with the RTS option `-DS`:
```
test.wasm: internal error: ASSERTION FAILED: file rts/sm/Storage.c, line 1216
(GHC version 9.12.2.20250327 for wasm32_unknown_wasi)
Please report this as a GHC bug: https://www.haskell.org/ghc/reportabug
```
What's the culprit? How do I look into this issue?
---
I manually reviewed & revised the patch, tested and submitted it.
-
7147370b
by Cheng Shao at 2025-05-20T17:22:19-04:00
compiler: do not allocate strings in bytecode assembler
This patch refactors the compiler to avoid allocating iserv buffers
for BCONPtrStr at assemble-time. Now BCONPtrStr ByteStrings are
recorded as a part of CompiledByteCode, and actual allocation only
happens at link-time. This refactoring is necessary for adding
bytecode serialization functionality, as explained by the revised
comments in this commit.
-
a67db612
by Cheng Shao at 2025-05-20T17:22:19-04:00
compiler: make bc_strs serializable
This commit makes the bc_strs field in CompiledByteCode serializable;
similar to previous commit, we preserve the ByteString directly and
defer the actual allocation to link-time, as mentioned in updated
comment.
-
5faf34ef
by Cheng Shao at 2025-05-20T17:22:19-04:00
compiler: make bc_itbls serializable
This commit makes bc_itbls in CompiledByteCode serializable. A
dedicated ConInfoTable datatype has been added in ghci which is the
recipe for dynamically making a datacon's info table, containing the
payload of the MkConInfoTable iserv message.
-
2abaf8c1
by Cheng Shao at 2025-05-20T17:22:19-04:00
compiler: remove FFIInfo bookkeeping in BCO
This commit removes the bc_ffis field from CompiledByteCode
completely, as well as all the related bookkeeping logic in
GHC.StgToByteCode. bc_ffis is actually *unused* in the rest of GHC
codebase! It is merely a list of FFIInfo, which is just a remote
pointer of the libffi ffi_cif struct; once we allocate the ffi_cif
struct and put its pointer in a CCALL instruction, we'll never free it
anyway. So there is no point of bookkeeping.
-
adb9e4d2
by Cheng Shao at 2025-05-20T17:22:19-04:00
compiler: make FFIInfo serializable in BCO
This commit makes all the FFIInfo needed in CCALL instructions
serializable. Previously, when doing STG to BCO lowering, we would
allocate a libffi ffi_cif struct and keep its remote pointer as
FFIInfo; but actually we can just keep the type signature as FFIInfo
and defer the actual allocation to link-time.
-
200f401b
by Cheng Shao at 2025-05-20T17:22:19-04:00
ghci: remove redundant NewBreakModule message
This commit removes the redundant NewBreakModule message from ghci: it
just allocates two strings! This functionality can be implemented with
existing MallocStrings in one iserv call.
-
ddaadca6
by Cheng Shao at 2025-05-20T17:22:19-04:00
compiler: make breakpoint module name and unit id serializable
This commit makes breakpoint module name and unit id serializable, in
BRK_FUN instructions as well as ModBreaks. We can simply keep the
module name and unit ids, and defer the buffer allocation to link
time.
-
a0fde202
by Cheng Shao at 2025-05-20T17:22:19-04:00
compiler: remove unused newModule
This commit removes the now unused newModule function from GHC.
-
68c8f140
by Cheng Shao at 2025-05-20T17:22:19-04:00
compiler: add BCONPtrFS for interned top level string literals in BCO
This commit adds BCONPtrFS as a BCO non-pointer literal kind, which
has the same semantics of BCONPtrStr, except it contains a FastString
instead of a ByteString. By using BCONPtrFS to represent top level
string literals that are already FastString in the compilation
pipeline, we enjoy the FastString interning logic and avoid allocating
a bunch of redundant ByteStrings for the same FastStrings, especially
when we lower the BRK_FUN instruction.
-
f2b532bc
by Peng Fan at 2025-05-20T17:23:15-04:00
hadrian: enable GHCi for loongarch64
-
8ded2330
by kwxm at 2025-05-20T17:24:07-04:00
Fix bugs in `integerRecipMod` and `integerPowMod`
This fixes #26017.
* `integerRecipMod x 1` now returns `(# 1 | #)` for all x; previously it
incorrectly returned `(# | () #)`, indicating failure.
* `integerPowMod 0 e m` now returns `(# | () #)` for e<0 and m>1, indicating
failure; previously it incorrectly returned `(# 0 | #)`.
-
c9abb87c
by Andreas Klebinger at 2025-05-20T17:24:50-04:00
Specialise: Don't float out constraint components.
It was fairly complex to do so and it doesn't seem to improve anything.
Nofib allocations were unaffected as well.
See also Historical Note [Floating dictionaries out of cases]
-
202b201c
by Andreas Klebinger at 2025-05-21T10:16:14-04:00
Interpreter: Add limited support for direct primop evaluation.
This commit adds support for a number of primops directly
to the interpreter. This avoids the indirection of going
through the primop wrapper for those primops speeding interpretation
of optimized code up massively.
Code involving IntSet runs about 25% faster with optimized core and these
changes. For core without breakpoints it's even more pronouced and I
saw reductions in runtime by up to 50%.
Running GHC itself in the interpreter was sped up by ~15% through this
change.
Additionally this comment does a few other related changes:
testsuite:
* Run foundation test in ghci and ghci-opt ways to test these
primops.
* Vastly expand the foundation test to cover all basic primops
by comparing result with the result of calling the wrapper.
Interpreter:
* When pushing arguments for interpreted primops extend each argument to
at least word with when pushing. This avoids some issues with big
endian. We can revisit this if it causes performance issues.
* Restructure the stack chunk check logic. There are now macros for
read accesses which might cross stack chunk boundries and macros which
omit the checks which are used when we statically know we access an
address in the current stack chunk.
-
67a177b4
by sheaf at 2025-05-21T10:17:04-04:00
QuickLook: do a shape test before unifying
This commit ensures we do a shape test before unifying. This ensures
we don't try to unify a TyVarTv with a non-tyvar, e.g.
alpha[tyv] := Int
On the way, we refactor simpleUnifyCheck:
1. Move the checkTopShape check into simpleUnifyCheck
2. Refactors simpleUnifyCheck to return a value of the new type
SimpleUnifyResult type. Now, simpleUnifyCheck returns "can unify",
"cannot unify" or "dunno" (with "cannot unify" being the new result
it can return). Now:
- touchabilityTest is included; it it fails we return "cannot unify"
- checkTopShape now returns "cannot unify" instead of "dunno" upon failure
3. Move the call to simpleUnifyCheck out of checkTouchableTyVarEq.
After that, checkTouchableTyVarEq becames a simple call to
checkTyEqRhs, so we inline it.
This allows the logic in canEqCanLHSFinish_try_unification to be simplified.
In particular, we now avoid calling 'checkTopShape' twice.
Two further changes suggested by Simon were also implemented:
- In canEqCanLHSFinish, if checkTyEqRhs returns PuFail with
'do_not_prevent_rewriting', we now **continue with this constraint**.
This allows us to use the constraint for rewriting.
- checkTyEqRhs now has a top-level check to avoid flattening a tyfam app
in a top-level equality of the form alpha ~ F tys, as this is
going around in circles. This simplifies the implementation without
any change in behaviour.
Fixes #25950
Fixes #26030
-
4020972c
by sheaf at 2025-05-21T10:17:04-04:00
FixedRuntimeRepError: omit unhelpful explanation
This commit tweaks the FixedRuntimeRepError case of pprTcSolverReportMsg,
to avoid including an explanation which refers to a type variable that
appears nowhere else.
For example, the old error message could look like the following:
The pattern binding does not have a fixed runtime representation.
Its type is:
T :: TYPE R
Cannot unify ‘R’ with the type variable ‘c0’
because the former is not a concrete ‘RuntimeRep’.
With this commit, we now omit the last two lines, because the concrete
type variable (here 'c0') does not appear in the type displayed to the
user (here 'T :: TYPE R').
-
6d058a69
by Andrea Bedini at 2025-05-21T16:00:51-04:00
Don't fail when ghcversion.h can't be found (#26018)
If ghcversion.h can't be found, don't try to include it. This happens
when there is no rts package in the package db and when -ghcversion-file
argument isn't passed.
Co-authored-by: Syvlain Henry <sylvain@haskus.fr>
-
b1212fbf
by Vladislav Zavialov at 2025-05-21T16:01:33-04:00
Implement -Wpattern-namespace-specifier (#25900)
In accordance with GHC Proposal #581 "Namespace-specified imports",
section 2.3 "Deprecate use of pattern in import/export lists", the
`pattern` namespace specifier is now deprecated.
Test cases: T25900 T25900_noext
-
e650ec3e
by Ben Gamari at 2025-05-23T03:42:46-04:00
base: Forward port changelog language from 9.12
-
94cd9ca4
by Ben Gamari at 2025-05-23T03:42:46-04:00
base: Fix RestructuredText-isms in changelog
-
7722232c
by Ben Gamari at 2025-05-23T03:42:46-04:00
base: Note strictness changes made in 4.16.0.0
Addresses #25886.
-
3f4b823c
by Ben Gamari at 2025-05-23T03:43:28-04:00
rts/linker: Factor out ProddableBlocks machinery
-
6e23fef2
by Ben Gamari at 2025-05-23T03:43:28-04:00
rts/linker: Improve efficiency of proddable blocks structure
Previously the linker's "proddable blocks" check relied on a simple
linked list of spans. This resulted in extremely poor complexity while
linking objects with lots of small sections (e.g. objects built with
split sections).
Rework the mechanism to instead use a simple interval set implemented
via binary search.
Fixes #26009.
-
ea74860c
by Ben Gamari at 2025-05-23T03:43:28-04:00
testsuite: Add simple functional test for ProddableBlockSet
-
74c4db46
by Ben Gamari at 2025-05-23T03:43:28-04:00
rts/linker/PEi386: Drop check for LOAD_LIBRARY_SEARCH_*_DIRS
The `LOAD_LIBRARY_SEARCH_USER_DIRS` and
`LOAD_LIBRARY_SEARCH_DEFAULT_DIRS` were introduced in Windows Vista and
have been available every since. As we no longer support Windows XP we
can drop this check.
Addresses #26009.
-
972d81d6
by Ben Gamari at 2025-05-23T03:43:28-04:00
rts/linker/PEi386: Clean up code style
-
8a1073a5
by Ben Gamari at 2025-05-23T03:43:28-04:00
rts/Hash: Factor out hashBuffer
This is a useful helper which can be used for non-strings as well.
-
44f509f2
by Ben Gamari at 2025-05-23T03:43:28-04:00
rts/linker/PEi386: Fix incorrect use of break in nested for
Previously the happy path of PEi386 used `break` in a double-`for` loop
resulting in redundant calls to `LoadLibraryEx`.
Fixes #26052.
-
bfb12783
by Ben Gamari at 2025-05-23T03:43:28-04:00
rts: Correctly mark const arguments
-
08469ff8
by Ben Gamari at 2025-05-23T03:43:28-04:00
rts/linker/PEi386: Don't repeatedly load DLLs
Previously every DLL-imported symbol would result in a call to
`LoadLibraryEx`. This ended up constituting over 40% of the runtime of
`ghc --interactive -e 42` on Windows. Avoid this by maintaining a
hash-set of loaded DLL names, skipping the call if we have already
loaded the requested DLL.
Addresses #26009.
-
823d1ccf
by Ben Gamari at 2025-05-23T03:43:28-04:00
rts/linker: Expand comment describing ProddableBlockSet
-
e9de9e0b
by Sylvain Henry at 2025-05-23T15:12:34-04:00
Remove emptyModBreaks
Remove emptyModBreaks and track the absence of ModBreaks with `Maybe
ModBreaks`. It avoids testing for null pointers...
-
17db44c5
by Ben Gamari at 2025-05-23T15:13:16-04:00
base: Expose Backtraces constructor and fields
This was specified in the proposal (CLC #199) yet somehow didn't make it
into the implementation.
Fixes #26049.
-
b08c08ae
by soulomoon at 2025-05-28T01:57:23+08:00
Refactor handling of imported COMPLETE pragmas
from the HPT
Previously, we imported COMPLETE pragmas from all modules in the Home
Package Table (HPT) during type checking. However, since !13675, there
may be non-below modules in the HPT from the dependency tree that we do
not want to import COMPLETE pragmas from. This refactor changes the way
we handle COMPLETE pragmas from the HPT to only import them from modules
that are "below" the current module in the HPT.
- Add hugCompleteSigsBelow to filter COMPLETE pragmas from "below"
modules in the HPT, mirroring hugRulesBelow.
- Move responsibility for calling hugCompleteSigsBelow to tcRnImports,
storing the result in the new tcg_complete_match_env field of TcGblEnv.
- Update getCompleteMatchesTcM to use tcg_complete_match_env.
This refactor only affects how COMPLETE pragmas are imported from the
HPT, imports from external packages are unchanged.
-
16014bf8
by Hécate Kleidukos at 2025-05-28T20:09:34-04:00
Expose all of Backtraces' internals for ghc-internal
Closes #26049
-
a0adc30d
by Ryan Hendrickson at 2025-05-30T14:12:52-04:00
haddock: Fix links to type operators
-
7b64697c
by Mario Blažević at 2025-05-30T14:13:41-04:00
Introduce parenBreakableList and use it in ppHsContext
-
5f213bff
by fendor at 2025-06-02T09:16:24+02:00
Make GHCi commands compatible with multiple home units
=== Design
We enable all GHCi features that were previously guarded by the `inMulti`
option.
GHCi supported multiple home units up to a certain degree for quite a while now.
The supported feature set was limited, due to a design impasse:
One of the home units must be "active", e.g., there must be one `HomeUnit`
whose `UnitId` is "active" which is returned when calling
```haskell
do
hscActiveUnitId <$> getSession
```
This makes sense in a GHC session, since you are always compiling a particular
Module, but it makes less intuitive sense in an interactive session.
Given an expression to evaluate, we can't easily tell in which "context" the expression
should be parsed, typechecked and evaluated.
That's why initially, most of GHCi features, except for `:reload`ing were disabled
if the GHCi session had more than one `HomeUnitEnv`.
We lift this restriction, enabling all features of GHCi for the multiple home unit case.
To do this, we fundamentally change the `HomeUnitEnv` graph to be multiple home unit first.
Instead of differentiating the case were we have a single home unit and multiple,
we now always set up a multiple home unit session that scales seamlessly to an arbitrary
amount of home units.
We introduce two new `HomeUnitEnv`s that are always added to the `HomeUnitGraph`.
They are:
The "interactive-ghci", called the `interactiveGhciUnit`, contains the same
`DynFlags` that are used by the `InteractiveContext` for interactive evaluation
of expressions.
This `HomeUnitEnv` is only used on the prompt of GHCi, so we may refer to it as
"interactive-prompt" unit.
See Note [Relation between the `InteractiveContext` and `interactiveGhciUnitId`]
for discussing its role.
And the "interactive-session"", called `interactiveSessionUnit` or
`interactiveSessionUnitId`, which is used for loading Scripts into
GHCi that are not `Target`s of any home unit, via `:load` or `:add`.
Both of these "interactive" home units depend on all other `HomeUnitEnv`s that
are passed as arguments on the cli.
Additionally, the "interactive-ghci" unit depends on `interactive-session`.
We always evaluate expressions in the context of the
"interactive-ghci" session.
Since "interactive-ghci" depends on all home units, we can import any `Module`
from the other home units with ease.
As we have a clear `HomeUnitGraph` hierarchy, we can set `interactiveGhciUnitId`
as the active home unit for the full duration of the GHCi session.
In GHCi, we always set `interactiveGhciUnitId` to be the currently active home unit.
=== Implementation Details
Given this design idea, the implementation is relatively straight
forward.
The core insight is that a `ModuleName` is not sufficient to identify a
`Module` in the `HomeUnitGraph`. Thus, large parts of the PR is simply
about refactoring usages of `ModuleName` to prefer `Module`, which has a
`Unit` attached and is unique over the `HomeUnitGraph`.
Consequentially, most usages of `lookupHPT` are likely to be incorrect and have
been replaced by `lookupHugByModule` which is keyed by a `Module`.
In `GHCi/UI.hs`, we make sure there is only one location where we are
actually translating `ModuleName` to a `Module`:
* `lookupQualifiedModuleName`
If a `ModuleName` is ambiguous, we detect this and report it to the
user.
To avoid repeated lookups of `ModuleName`s, we store the `Module` in the
`InteractiveImport`, which additionally simplifies the interface
loading.
A subtle detail is that the `DynFlags` of the `InteractiveContext` are
now stored both in the `HomeUnitGraph` and in the `InteractiveContext`.
In UI.hs, there are multiple code paths where we are careful to update
the `DynFlags` in both locations.
Most importantly in `addToProgramDynFlags`.
---
There is one metric increase in this commit:
-------------------------
Metric Increase:
T4029
-------------------------
It is an increase from 14.4 MB to 16.1 MB (+11.8%) which sounds like a
pretty big regression at first.
However, we argue this increase is solely caused by using more data
structures for managing multiple home units in the GHCi session.
In particular, due to the design decision of using three home units, the
base memory usage increases... but by how much?
A big contributor is the `UnitState`, of which we have three now, which
on its own 260 KB per instance. That makes an additional memory usage of
520 KB, already explaining a third of the overall memory usage increase.
Then we store more elements in the `HomeUnitGraph`, we have more
`HomeUnitEnv` entries, etc...
While we didn't chase down each byte, we looked at the memory usage over time
for both `-hi` and `-hT` profiles and can say with confidence while the memory
usage increased slightly, we did not introduce any space leak, as
the graph looks almost identical as the memory usage graph of GHC HEAD.
---
Adds testcases for GHCi multiple home units session
* Test truly multiple home unit sessions, testing reload logic and code evaluation.
* Test that GHCi commands such as `:all-types`, `:browse`, etc., work
* Object code reloading for home modules
* GHCi debugger multiple home units session
-
de603d01
by fendor at 2025-06-02T09:16:24+02:00
Update "loading compiled code" GHCi documentation
To use object code in GHCi, the module needs to be compiled for use in
GHCi. To do that, users need to compile their modules with:
* `-dynamic`
* `-this-unit-id interactive-session`
Otherwise, the interface files will not match.
-
b255a8ca
by Vladislav Zavialov at 2025-06-02T16:00:12-04:00
docs: Fix code example for NoListTuplePuns
Without the fix, the example produces an error:
Test.hs:11:3: error: [GHC-45219]
• Data constructor ‘Tuple’ returns type ‘Tuple2 a b’
instead of an instance of its parent type ‘Tuple a’
• In the definition of data constructor ‘Tuple’
In the data type declaration for ‘Tuple’
Fortunately, a one line change makes it compile.
-
6558467c
by Ryan Hendrickson at 2025-06-06T05:46:58-04:00
haddock: Parse math even after ordinary characters
Fixes a bug where math sections were not recognized if preceded by a
character that isn't special (like space or a markup character).
-
265d0024
by ARATA Mizuki at 2025-06-06T05:47:48-04:00
AArch64 NCG: Fix sub-word arithmetic right shift
As noted in Note [Signed arithmetic on AArch64], we should zero-extend sub-word values.
Fixes #26061
-
05e9be18
by Simon Hengel at 2025-06-06T05:48:35-04:00
Allow Unicode in "message" and "hints" with -fdiagnostics-as-json
(fixes #26075)
-
bfa6b70f
by ARATA Mizuki at 2025-06-06T05:49:24-04:00
x86 NCG: Fix code generation of bswap64 on i386
Co-authored-by: sheaf <sam.derbyshire@gmail.com>
Fix #25601
-
35826d8b
by Matthew Pickering at 2025-06-08T22:00:41+01:00
Hadrian: Add option to generate .hie files for stage1 libraries
The +hie_files flavour transformer can be enabled to produce hie files
for stage1 libraries. The hie files are produced in the
"extra-compilation-artifacts" folder and copied into the resulting
bindist.
At the moment the hie files are not produced for the release flavour,
they add about 170M to the final bindist.
Towards #16901
-
e2467dbd
by Ryan Hendrickson at 2025-06-09T13:07:05-04:00
Fix various failures to -fprint-unicode-syntax
-
1d99d3e4
by maralorn at 2025-06-12T03:47:39-04:00
Add necessary flag for js linking
-
974d5734
by maralorn at 2025-06-12T03:47:39-04:00
Don’t use additional linker flags to detect presence of -fno-pie in configure.ac
This mirrors the behavior of ghc-toolchain
-
1e9eb118
by Andrew Lelechenko at 2025-06-12T03:48:21-04:00
Add HasCallStack to Control.Monad.Fail.fail
CLC proposal https://github.com/haskell/core-libraries-committee/issues/327
2% compile-time allocations increase in T3064, likely because `fail`
is now marginally more expensive to compile.
Metric Increase:
T3064
-
6d12060f
by meooow25 at 2025-06-12T14:26:07-04:00
Bump containers submodule to 0.8
Also
* Disable -Wunused-imports for containers
* Allow containers-0.8 for in-tree packages
* Bump some submodules so that they allow containers-0.8. These are not
at any particular versions.
* Remove unused deps containers and split from ucd2haskell
* Fix tests affected by the new containers and hpc-bin
-
537bd233
by Peng Fan at 2025-06-12T14:27:02-04:00
NCG/LA64: Optimize code generation and reduce build-directory size.
1. makeFarBranches: Prioritize fewer instruction sequences.
2. Prefer instructions with immediate numbers to reduce register moves,
e.g. andi,ori,xori,addi.
3. Ppr: Remove unnecessary judgments.
4. genJump: Avoid "ld+jr" as much as possible.
5. BCOND and BCOND1: Implement conditional jumps with two jump ranges,
with limited choice of the shortest.
6. Implement FSQRT, CLT, CTZ.
7. Remove unnecessary code.
-
19f20861
by Simon Peyton Jones at 2025-06-13T09:51:11-04:00
Improve redundant constraints for instance decls
Addresses #25992, which showed that the default methods
of an instance decl could make GHC fail to report redundant
constraints.
Figuring out how to do this led me to refactor the computation
of redundant constraints. See the entirely rewritten
Note [Tracking redundant constraints]
in GHC.Tc.Solver.Solve
-
1d02798e
by Matthew Pickering at 2025-06-13T09:51:54-04:00
Refactor the treatment of nested Template Haskell splices
* The difference between a normal splice, a quasiquoter and implicit
splice caused by lifting is stored in the AST after renaming.
* Information that the renamer learns about splices is stored in the
relevant splice extension points (XUntypedSpliceExpr, XQuasiQuote).
* Normal splices and quasi quotes record the flavour of splice
(exp/pat/dec etc)
* Implicit lifting stores information about why the lift was attempted,
so if it fails, that can be reported to the user.
* After renaming, the decision taken to attempt to implicitly lift a
variable is stored in the `XXUntypedSplice` extension field in the
`HsImplicitLiftSplice` constructor.
* Since all the information is stored in the AST, in `HsUntypedSplice`,
the type of `PendingRnSplice` now just stores a `HsUntypedSplice`.
* Error messages since the original program can be easily
printed, this is noticeable in the case of implicit lifting.
* The user-written syntax is directly type-checked. Before, some
desugaring took place in the
* Fixes .hie files to work better with nested splices (nested splices
are not indexed)
* The location of the quoter in a quasiquote is now located, so error
messages will precisely point to it (and again, it is indexed by hie
files)
In the future, the typechecked AST should also retain information about
the splices and the specific desugaring being left to the desugarer.
Also, `runRnSplice` should call `tcUntypedSplice`, otherwise the
typechecking logic is duplicated (see the `QQError` and `QQTopError`
tests for a difference caused by this).
-
f93798ba
by Cheng Shao at 2025-06-13T09:52:35-04:00
libffi: update to 3.5.1
Bumps libffi submodule.
-
c7aa0c10
by Andreas Klebinger at 2025-06-15T05:47:24-04:00
Revert "Specialise: Don't float out constraint components."
This reverts commit c9abb87ccc0c91cd94f42b3e36270158398326ef.
Turns out two benchmarks from #19747 regresses by a factor of 7-8x if
we do not float those out.
-
fd998679
by Krzysztof Gogolewski at 2025-06-15T05:48:06-04:00
Fix EPT enforcement when mixing unboxed tuples and non-tuples
The code was assuming that an alternative cannot be returning a normal
datacon and an unboxed tuple at the same time. However, as seen in #26107,
this can happen when using a GADT to refine the representation type.
The solution is just to conservatively return TagDunno.
-
e64b3f16
by ARATA Mizuki at 2025-06-17T10:13:42+09:00
MachRegs.h: Don't define NO_ARG_REGS when a XMM register is defined
On i386, MAX_REAL_VANILLA_REG is 1, but MAX_REAL_XMM_REG is 4.
If we define NO_ARG_REGS on i386, programs that use SIMD vectors may segfault.
Closes #25985
A couple of notes on the BROKEN_TESTS field:
* This fixes the segfault from T25062_V16.
* The failure from T22187_run was fixed in an earlier commit (see #25561),
but BROKEN_TESTS was missed at that time. Now should be a good time to
mark it fixed.
-
3e7c6b4d
by Matthew Pickering at 2025-06-18T15:34:04-04:00
Improve error messages when implicit lifting fails
This patch concerns programs which automatically try to fix level errors
by inserting `Lift`. For example:
```
foo x = [| x |]
~>
foo x = [| $(lift x) |]
```
Before, there were two problems with the message.
1. (#26031), the location of the error was reported as the whole
quotation.
2. (#26035), the message just mentions there is no Lift instance, but
gives no indicate why the user program needed a Lift instance in the
first place.
This problem is especially bad when you disable
`ImplicitStagePersistence`, so you just end up with a confusing "No
instance for" message rather than an error message about levels
This patch fixes both these issues.
Firstly, `PendingRnSplice` differentiates between a user-written splice
and an implicit lift. Then, the Lift instance is precisely requested
with a specific origin in the typechecker. If the instance fails to be
solved, the message is reported using the `TcRnBadlyLevelled`
constructor (like a normal level error).
Fixes #26031, #26035
-
44b8cee2
by Cheng Shao at 2025-06-18T15:34:46-04:00
testsuite: add T26120 marked as broken
-
894a04f3
by Cheng Shao at 2025-06-18T15:34:46-04:00
compiler: fix GHC.SysTools.Ar archive member size writing logic
This patch fixes a long-standing bug in `GHC.SysTools.Ar` that emits
the wrong archive member size in each archive header. It should encode
the exact length of the member payload, excluding any padding byte,
otherwise malformed archive that extracts a broken object with an
extra trailing byte could be created.
Apart from the in-tree `T26120` test, I've also created an out-of-tree
testsuite at https://github.com/TerrorJack/ghc-ar-quickcheck that
contains QuickCheck roundtrip tests for `GHC.SysTools.Ar`. With this
fix, simple roundtrip tests and `writeGNUAr`/GNU `ar` roundtrip test
passes. There might be more bugs lurking in here, but this patch is
still a critical bugfix already.
Fixes #26120 #22586.
Co-authored-by: Codex <codex@openai.com>
-
f677ab5f
by Lauren Yim at 2025-06-18T15:35:37-04:00
fix some typos in the warnings page in the user guide
-
b968e1c1
by Rodrigo Mesquita at 2025-06-18T15:36:18-04:00
Add a frozen callstack to throwGhcException
Fixes #25956
-
a5e0c3a3
by fendor at 2025-06-18T15:36:59-04:00
Update using.rst to advertise full mhu support for GHCi
-
d3e60e97
by Ryan Scott at 2025-06-18T22:29:21-04:00
Deprecate -Wdata-kinds-tc, make DataKinds issues in typechecker become errors
!11314 introduced the `-Wdata-kinds-tc` warning as part of a fix for #22141.
This was a temporary stopgap measure to allow users who were accidentally
relying on code which needed the `DataKinds` extension in order to typecheck
without having to explicitly enable the extension.
Now that some amount of time has passed, this patch deprecates
`-Wdata-kinds-tc` and upgrades any `DataKinds`-related issues in the
typechecker (which were previously warnings) into errors.
-
fd5b5177
by Ryan Hendrickson at 2025-06-18T22:30:06-04:00
haddock: Add redact-type-synonyms pragma
`{-# OPTIONS_HADDOCK redact-type-synonyms #-}` pragma will hide the RHS
of type synonyms, and display the result kind instead, if the RHS
contains any unexported types.
-
fbc0b92a
by Vladislav Zavialov at 2025-06-22T04:25:16+03:00
Visible forall in GADTs (#25127)
Add support for visible dependent quantification `forall a -> t` in
types of data constructors, e.g.
data KindVal a where
K :: forall k.
forall (a::k) -> -- now allowed!
k ->
KindVal a
For details, see docs/users_guide/exts/required_type_arguments.rst,
which has gained a new subsection.
DataCon in compiler/GHC/Core/DataCon.hs
---------------------------------------
The main change in this patch is that DataCon, the Core representation
of a data constructor, now uses a different type to store user-written
type variable binders:
- dcUserTyVarBinders :: [InvisTVBinder]
+ dcUserTyVarBinders :: [TyVarBinder]
where
type TyVarBinder = VarBndr TyVar ForAllTyFlag
type InvisTVBinder = VarBndr TyVar Specificity
and
data Specificity = InferredSpec | SpecifiedSpec
data ForAllTyFlag = Invisible Specificity | Required
This change necessitates some boring, mechanical changes scattered
throughout the diff:
... is now used in place of ...
-----------------+---------------
TyVarBinder | InvisTVBinder
IfaceForAllBndr | IfaceForAllSpecBndr
Specified | SpecifiedSpec
Inferred | InferredSpec
mkForAllTys | mkInvisForAllTys
additionally,
tyVarSpecToBinders -- added or removed calls
ifaceForAllSpecToBndrs -- removed calls
Visibility casts in mkDataConRep
--------------------------------
Type abstractions in Core (/\a. e) always have type (forall a. t)
because coreTyLamForAllTyFlag = Specified. This is also true of data
constructor workers. So we may be faced with the following:
data con worker: (forall a. blah)
data con wrapper: (forall a -> blah)
In this case the wrapper must use a visibility cast (e |> ForAllCo ...)
with appropriately set fco_vis{L,R}. Relevant functions:
mkDataConRep in compiler/GHC/Types/Id/Make.hs
dataConUserTyVarBindersNeedWrapper in compiler/GHC/Core/DataCon.hs
mkForAllVisCos in compiler/GHC/Core/Coercion.hs
mkCoreTyLams in compiler/GHC/Core/Make.hs
mkWpForAllCast in compiler/GHC/Tc/Types/Evidence.hs
More specifically:
- dataConUserTyVarBindersNeedWrapper has been updated to answer "yes"
if there are visible foralls in the type of the data constructor.
- mkDataConRep now uses mkCoreTyLams to generate the big lambda
abstractions (/\a b c. e) in the data con wrapper.
- mkCoreTyLams is a variant of mkCoreLams that applies visibility casts
as needed. It similar in purpose to the pre-existing mkWpForAllCast,
so the common bits have been factored out into mkForAllVisCos.
ConDecl in compiler/Language/Haskell/Syntax/Decls.hs
----------------------------------------------------
The surface syntax representation of a data constructor declaration is
ConDecl. In accordance with the proposal, only GADT syntax is extended
with support for visible forall, so we are interested in ConDeclGADT.
ConDeclGADT's field con_bndrs has been renamed to con_outer_bndrs
and is now accompanied by con_inner_bndrs:
con_outer_bndrs :: XRec pass (HsOuterSigTyVarBndrs pass)
con_inner_bndrs :: [HsForAllTelescope pass]
Visible foralls always end up in con_inner_bndrs. The outer binders are
stored and processed separately to support implicit quantification and
the forall-or-nothing rule, a design established by HsSigType.
A side effect of this change is that even in absence of visible foralls,
GHC now permits multiple invisible foralls, e.g.
data T a where { MkT :: forall a b. forall c d. ... -> T a }
But of course, this is done in service of making at least some of these
foralls visible. The entire compiler front-end has been updated to deal
with con_inner_bndrs. See the following modified or added functions:
Parser:
mkGadtDecl in compiler/GHC/Parser/PostProcess.hs
splitLHsGadtTy in compiler/GHC/Hs/Type.hs
Pretty-printer:
pprConDecl in compiler/GHC/Hs/Decls.hs
pprHsForAllTelescope in compiler/GHC/Hs/Type.hs
Renamer:
rnConDecl in compiler/GHC/Rename/Module.hs
bindHsForAllTelescopes in compiler/GHC/Rename/HsType.hs
extractHsForAllTelescopes in compiler/GHC/Rename/HsType.hs
Type checker:
tcConDecl in compiler/GHC/Tc/TyCl.hs
tcGadtConTyVarBndrs in compiler/GHC/Tc/Gen/HsType.hs
Template Haskell
----------------
The TH AST is left unchanged for the moment to avoid breakage. An
attempt to quote or reify a data constructor declaration with visible
forall in its type will result an error:
data ThRejectionReason -- in GHC/HsToCore/Errors/Types.hs
= ...
| ThDataConVisibleForall -- new error constructor
However, as noted in the previous section, GHC now permits multiple
invisible foralls, and TH was updated accordingly. Updated code:
repC in compiler/GHC/HsToCore/Quote.hs
reifyDataCon in compiler/GHC/Tc/Gen/Splice.hs
ppr @Con in libraries/ghc-boot-th/GHC/Boot/TH/Ppr.hs
Pattern matching
----------------
Everything described above concerns data constructor declarations, but
what about their use sites? Now it is trickier to type check a pattern
match fn(Con a b c)=... because we can no longer assume that a,b,c are
all value arguments. Indeed, some or all of them may very well turn out
to be required type arguments.
To that end, see the changes to:
tcDataConPat in compiler/GHC/Tc/Gen/Pat.hs
splitConTyArgs in compiler/GHC/Tc/Gen/Pat.hs
and the new helpers split_con_ty_args, zip_pats_bndrs.
This is also the reason the TcRnTooManyTyArgsInConPattern error
constructor has been removed. The new code emits TcRnArityMismatch
or TcRnIllegalInvisibleTypePattern.
Summary
-------
DataCon, ConDecl, as well as all related functions have been updated to
support required type arguments in data constructors.
Test cases:
HieGadtConSigs GadtConSigs_th_dump1 GadtConSigs_th_pprint1
T25127_data T25127_data_inst T25127_infix
T25127_newtype T25127_fail_th_quote T25127_fail_arity
TyAppPat_Tricky
Co-authored-by: mniip <mniip@mniip.com>
-
ae003a3a
by Teo Camarasu at 2025-06-23T05:21:48-04:00
linters: lint-whitespace: bump upper-bound for containers
The version of containers was bumped in https://gitlab.haskell.org/ghc/ghc/-/merge_requests/13989
-
0fb37893
by Matthew Pickering at 2025-06-23T13:55:10-04:00
Move ModuleGraph into UnitEnv
The ModuleGraph is a piece of information associated with the
ExternalPackageState and HomeUnitGraph. Therefore we should store it
inside the HomeUnitEnv.
-
3bf6720e
by soulomoon at 2025-06-23T13:55:52-04:00
Remove hptAllFamInstances usage during upsweep
Fixes #26118
This change eliminates the use of hptAllFamInstances during the upsweep phase,
as it could access non-below modules from the home package table.
The following updates were made:
* Updated checkFamInstConsistency to accept an explicit ModuleEnv FamInstEnv
parameter and removed the call to hptAllFamInstances.
* Adjusted hugInstancesBelow so we can construct ModuleEnv FamInstEnv
from its result,
* hptAllFamInstances and allFamInstances functions are removed.
-
83ee7b78
by Ben Gamari at 2025-06-24T05:02:07-04:00
configure: Don't force value of OTOOL, etc. if not present
Previously if `otool` and `install_name_tool` were not present they
would be overridden by `fp_settings.m4`. This logic was introduced in
4ff93292243888545da452ea4d4c1987f2343591 without explanation.
-
9329c9e1
by Ben Gamari at 2025-06-24T05:02:07-04:00
ghc-toolchain: Add support for otool, install_name_tool
Fixes part of ghc#23675.
-
25f5c998
by Ben Gamari at 2025-06-24T05:02:08-04:00
ghc-toolchain: Add support for llc, opt, llvm-as
Fixes #23675.
-
51d150dd
by Rodrigo Mesquita at 2025-06-24T05:02:08-04:00
hadrian: Use settings-use-distro-mingw directly
The type `ToolchainSetting` only made sense when we had more settings to
fetch from the system config file. Even then "settings-use-distro-mingw"
is arguably not a toolchain setting.
With the fix for #23675, all toolchain tools were moved to the
`ghc-toolchain` `Toolchain` format. Therefore, we can inline
`settings-use-distro-mingw` accesses and delete `ToolchainSetting`.
-
dcf68a83
by Rodrigo Mesquita at 2025-06-24T05:02:08-04:00
configure: Check LlvmTarget exists for LlvmAsFlags
If LlvmTarget was empty, LlvmAsFlags would be just "--target=".
If it is empty now, simply keep LlvmAsFlags empty.
ghc-toolchain already does this right. This fix makes the two
configurations match up.
-
580a3353
by Ben Gamari at 2025-06-24T05:02:51-04:00
rts/linker/LoadArchive: Use bool
Improve type precision by using `bool` instead of `int` and `StgBool`.
-
76d1041d
by Ben Gamari at 2025-06-24T05:02:51-04:00
rts/linker/LoadArchive: Don't rely on file extensions for identification
Previously archive members would be identified via their file extension,
as described in #13103. We now instead use a more principled approach,
relying on the magic number in the member's header.
As well, we refactor treatment of archive format detection to improve
code clarity and error handling.
Closes #13103.
-
4b748a99
by Teo Camarasu at 2025-06-24T15:31:07-04:00
template-haskell: improve changelog
stable -> more stable, just to clarify that this interface isn't fully stable.
errornously -> mistakenly: I typod this and also let's go for a simpler word
-
e358e477
by Sylvain Henry at 2025-06-24T15:31:58-04:00
Bump stack resolver to use GHC 9.6.7
Cf #26139
-
4bf5eb63
by fendor at 2025-06-25T17:05:43-04:00
Teach `:reload` about multiple home units
`:reload` needs to lookup the `ModuleName` and must not assume the given
`ModuleName` is in the current `HomeUnit`.
We add a new utility function which allows us to find a `HomeUnitModule`
instead of a `Module`.
Further, we introduce the `GhciCommandError` type which can be used to
abort the execution of a GHCi command.
This error is caught and printed in a human readable fashion.
-
b3d97bb3
by fendor at 2025-06-25T17:06:25-04:00
Implement `-fno-load-initial-targets` flag
We add the new flag `-fno-load-initial-targets` which doesn't load all `Target`s
immediately but only computes the module graph for all `Target`s.
The user can then decide to load modules from that module graph using
the syntax:
ghci> :reload <Mod>
This will load everything in the module graph up to `Mod`.
The user can return to the initial state by using the builtin target
`none` to unload all modules.
ghci> :reload none
Is in principle identical to starting a new session with the
`-fno-load-initial-targets` flag.
The `-fno-load-initial-targets` flag allows for faster startup time of GHCi when a
user has lots of `Target`s.
We additionally extend the `:reload` command to accept multiple
`ModuleName`s. For example:
ghci> :reload <Mod1> <Mod2>
Loads all modules up to the modules `Mod1` and `Mod2`.
-
49f44e52
by Teo Camarasu at 2025-06-26T04:19:51-04:00
Expose ghc-internal unit id through the settings file
This in combination with the unit id of the compiler library allows
cabal to know of the two unit ids that should not be reinstalled (in
specific circumstances) as:
- when using plugins, we want to link against exactly the compiler unit
id
- when using TemplateHaskell we want to link against exactly the package
that contains the TemplateHaskell interfaces, which is `ghc-internal`
See: <https://github.com/haskell/cabal/issues/10087>
Resolves #25282
-
499c4efe
by Bryan Richter at 2025-06-26T04:20:33-04:00
CI: Fix and clean up capture of timings
* Fixes the typo that caused 'cat ci-timings' to report "no such file or
directory"
* Gave ci_timings.txt a file extension so it may play better with other
systems
* Fixed the use of time_it so all times are recorded
* Fixed time_it to print name along with timing
-
86c90c9e
by Bryan Richter at 2025-06-26T04:20:33-04:00
CI: Update collapsible section usage
The syntax apparently changed at some point.
-
04308ee4
by Bryan Richter at 2025-06-26T04:20:33-04:00
CI: Add more collapsible sections
-
43b606bb
by Florian Ragwitz at 2025-06-27T16:31:26-04:00
Tick uses of wildcard/pun field binds as if using the record selector function
Fixes #17834.
See Note [Record-selector ticks] for additional reasoning behind this as well
as an overview of the implementation details and future improvements.
-
d4952549
by Ben Gamari at 2025-06-27T16:32:08-04:00
testsuite/caller-cc: Make CallerCc[123] less sensitive
These were previously sensitive to irrelevant changes in program
structure. To avoid this we filter out all by lines emitted by the
-fcaller-cc from the profile.
-
8d33d048
by Berk Özkütük at 2025-07-07T20:42:20-04:00
Consider `PromotedDataCon` in `tyConStupidTheta`
Haddock checks data declarations for the stupid theta so as not to
pretty-print them as empty contexts. Type data declarations end up as
`PromotedDataCon`s by the time Haddock performs this check, causing a
panic. This commit extends `tyConStupidTheta` so that it returns an
empty list for `PromotedDataCon`s. This decision was guided by the fact
that type data declarations never have data type contexts (see (R1) in
Note [Type data declarations]).
Fixes #25739.
-
a26243fd
by Ryan Hendrickson at 2025-07-07T20:43:07-04:00
haddock: Document instances from other packages
When attaching instances to `Interface`s, it isn't enough just to look
for instances in the list of `Interface`s being processed. We also need
to look in the modules on which they depend, including those outside of
this package.
Fixes #25147.
Fixes #26079.
-
0fb24420
by Rodrigo Mesquita at 2025-07-07T20:43:49-04:00
hadrian: Fallback logic for internal interpreter
When determining whether to build the internal interpreter, the `make`
build system had a fallback case for platforms not in the list of
explicitly-supported operating systems and architectures.
This fallback says we should try to build the internal interpreter if
building dynamic GHC programs (if the architecture is unknown).
Fixes #24098
-
fe925bd4
by Ben Gamari at 2025-07-07T20:44:30-04:00
users-guide: Reference Wasm FFI section
-
5856284b
by Ben Gamari at 2025-07-07T20:44:30-04:00
users-guide: Fix too-short heading warning
-
a48dcdf3
by Duncan Coutts at 2025-07-07T20:45:18-04:00
Reorganise documentation for allocate* functions
Consolodate interface information into the .h file, keeping just
implementation details in the .c file.
Use Notes stlye in the .h file and refer to notes from the .c file.
-
de5b528c
by Duncan Coutts at 2025-07-07T20:45:18-04:00
Introduce common utilities for allocating arrays
The intention is to share code among the several places that do this
already.
-
b321319d
by Duncan Coutts at 2025-07-07T20:45:18-04:00
Use new array alloc utils in Heap.c
The CMM primop can now report heap overflow.
-
1d557ffb
by Duncan Coutts at 2025-07-07T20:45:18-04:00
Use new array alloc utils in ThreadLabels.c
Replacing a local utility.
-
e59a1430
by Duncan Coutts at 2025-07-07T20:45:18-04:00
Use new array alloc utils in Threads.c
Replacing local open coded version.
-
482df1c9
by Duncan Coutts at 2025-07-07T20:45:18-04:00
Add exitHeapOverflow helper utility
This will be useful with the array alloc functions, since unlike
allocate/allocateMaybeFail, they do not come in two versions. So if it's
not convenient to propagate failure, then one can use this.
-
4d3ec8f9
by Duncan Coutts at 2025-07-07T20:45:18-04:00
Use new array alloc utils in Weak.c
Also add a cpp macro CCS_SYSTEM_OR_NULL which does what it says. The
benefit of this is that it allows us to referece CCS_SYSTEM even when
we're not in PROFILING mode. That makes abstracting over profiling vs
normal mode a lot easier.
-
0c4f2fde
by Duncan Coutts at 2025-07-07T20:45:18-04:00
Convert the array alloc primops to use the new array alloc utils
-
a3354ad9
by Duncan Coutts at 2025-07-07T20:45:18-04:00
While we're at it, add one missing 'likely' hint
To a cmm primops that raises an exception, like the others now do.
-
33b546bd
by meooow25 at 2025-07-07T20:46:09-04:00
Keep scanl' strict in the head on rewrite
`scanl'` forces elements to WHNF when the corresponding `(:)`s are
forced. The rewrite rule for `scanl'` missed forcing the first element,
which is fixed here with a `seq`.
-
8a69196e
by Rodrigo Mesquita at 2025-07-08T07:39:47-04:00
debugger/rts: Allow toggling step-in per thread
The RTS global flag `rts_stop_next_breakpoint` globally sets the
interpreter to stop at the immediate next breakpoint.
With this commit, single step mode can additionally be set per thread in
the TSO flag (TSO_STOP_NEXT_BREAKPOINT).
Being able to toggle "stop at next breakpoint" per thread is an
important requirement for implementing "stepping out" of a function in a
multi-threaded context.
And, more generally, having a per-thread flag for single-stepping paves the
way for multi-threaded debugging.
That said, when we want to enable "single step" mode for the whole
interpreted program we still want to stop at the immediate next
breakpoint, whichever thread it belongs to.
That's why we also keep the global `rts_stop_next_breakpoint` flag, with
`rts_enableStopNextBreakpointAll` and `rts_disableStopNextBreakpointAll` helpers.
Preparation for #26042
-
73d3f864
by Rodrigo Mesquita at 2025-07-08T07:39:47-04:00
docs: Case continuation BCOs
This commit documents a subtle interaction between frames for case BCOs
and their parents frames. Namely, case continuation BCOs may refer to
(non-local) variables that are part of the parent's frame.
The note expanding a bit on these details is called [Case continuation BCOs]
-
d7aeddcf
by Rodrigo Mesquita at 2025-07-08T07:39:47-04:00
debugger: Implement step-out feature
Implements support for stepping-out of a function (aka breaking right after
returning from a function) in the interactive debugger.
It also introduces a GHCi command :stepout to step-out of a function
being debugged in the interpreter. The feature is described as:
Stop at the first breakpoint immediately after returning from the current
function scope.
Known limitations: because a function tail-call does not push a stack
frame, if step-out is used inside of a function that was tail-called,
execution will not be returned to its caller, but rather its caller's
first non-tail caller. On the other hand, it means the debugger
follows the more realistic execution of the program.
In the following example:
.. code-block:: none
f = do
a
b <--- (1) set breakpoint then step in here
c
b = do
...
d <--- (2) step-into this tail call
d = do
...
something <--- (3) step-out here
...
Stepping-out will stop execution at the `c` invokation in `f`, rather than
stopping at `b`.
The key idea is simple: When step-out is enabled, traverse the runtime
stack until a continuation BCO is found -- and enable the breakpoint
heading that BCO explicitly using its tick-index.
The details are specified in `Note [Debugger: Step-out]` in `rts/Interpreter.c`.
Since PUSH_ALTS BCOs (representing case continuations) were never headed
by a breakpoint (unlike the case alternatives they push), we introduced
the BRK_ALTS instruction to allow the debugger to set a case
continuation to stop at the breakpoint heading the alternative that is
taken. This is further described in `Note [Debugger: BRK_ALTS]`.
Fixes #26042
-
5d9adf51
by Rodrigo Mesquita at 2025-07-08T07:39:47-04:00
debugger: Filter step-out stops by SrcSpan
To implement step-out, the RTS looks for the first continuation frame on
the stack and explicitly enables its entry breakpoint. However, some
continuations will be contained in the function from which step-out was
initiated (trivial example is a case expression).
Similarly to steplocal, we will filter the breakpoints at which the RTS
yields to the debugger based on the SrcSpan. When doing step-out, only
stop if the breakpoint is /not/ contained in the function from which we
initiated it.
This is especially relevant in monadic statements such as IO which is
compiled to a long chain of case expressions.
See Note [Debugger: Filtering step-out stops]
-
7677adcc
by Cheng Shao at 2025-07-08T07:40:29-04:00
compiler: make ModBreaks serializable
-
14f67c6d
by Rodrigo Mesquita at 2025-07-08T07:40:29-04:00
refactor: "Inspecting the session" moved from GHC
Moved utilities for inspecting the session from the GHC module to
GHC.Driver.Session.Inspect
Purely a clean up
-
9d3f484a
by Rodrigo Mesquita at 2025-07-08T07:40:30-04:00
cleanup: Pass the HUG to readModBreaks, not HscEnv
A minor cleanup. The associated history and setupBreakpoint functions
are changed accordingly.
-
b595f713
by Rodrigo Mesquita at 2025-07-08T07:40:30-04:00
cleanup: Move readModBreaks to GHC.Runtime.Interpreter
With some small docs changes
-
d223227a
by Rodrigo Mesquita at 2025-07-08T07:40:30-04:00
cleanup: Move interpreterProfiled to Interp.Types
Moves interpreterProfiled and interpreterDynamic to
GHC.Runtime.Interpreter.Types from GHC.Runtime.Interpreter.
-
7fdd0a3d
by Rodrigo Mesquita at 2025-07-08T07:40:30-04:00
cleanup: Don't import GHC in Debugger.Breakpoints
Remove the top-level
import GHC
from GHC.Runtime.Debugger.Breakpoints
This makes the module dependencies more granular and cleans up the
qualified imports from the code.
-
5e4da31b
by Rodrigo Mesquita at 2025-07-08T07:40:30-04:00
refactor: Use BreakpointId in Core and Ifaces
-
741ac3a8
by Rodrigo Mesquita at 2025-07-08T07:40:30-04:00
stg2bc: Derive BcM via ReaderT StateT
A small refactor that simplifies GHC.StgToByteCode by deriving-via the
Monad instances for BcM. This is done along the lines of previous
similar refactors like 72b54c0760bbf85be1f73c1a364d4701e5720465.
-
0414fcc9
by Rodrigo Mesquita at 2025-07-08T07:40:30-04:00
refact: Split InternalModBreaks out of ModBreaks
There are currently two competing ways of referring to a Breakpoint:
1. Using the Tick module + Tick index
2. Using the Info module + Info index
1. The Tick index is allocated during desugaring in `mkModBreaks`. It is
used to refer to a breakpoint associated to a Core Tick. For a given
Tick module, there are N Ticks indexed by Tick index.
2. The Info index is allocated during code generation (in StgToByteCode)
and uniquely identifies the breakpoints at runtime (and is indeed used
to determine which breakpoint was hit at runtime).
Why we need both is described by Note [Breakpoint identifiers].
For every info index we used to keep a `CgBreakInfo`, a datatype containing
information relevant to ByteCode Generation, in `ModBreaks`.
This commit splits out the `IntMap CgBreakInfo` out of `ModBreaks` into
a new datatype `InternalModBreaks`.
- The purpose is to separate the `ModBreaks` datatype, which stores
data associated from tick-level information which is fixed after
desugaring, from the unrelated `IntMap CgBreakInfo` information
accumulated during bytecode generation.
- We move `ModBreaks` to GHC.HsToCore.Breakpoints
The new `InternalModBreaks` simply combines the `IntMap CgBreakInfo`
with `ModBreaks`. After code generation we construct an
`InternalModBreaks` with the `CgBreakInfo`s we accumulated and the
existing `ModBreaks` and store that in the compiled BCO in `bc_breaks`.
- Note that we previously only updated the `modBreaks_breakInfo`
field of `ModBreaks` at this exact location, and then stored the
updated `ModBreaks` in the same `bc_breaks`.
- We put this new datatype in GHC.ByteCode.Breakpoints
The rest of the pipeline for which CgBreakInfo is relevant is
accordingly updated to also use `InternalModBreaks`
-
2a097955
by Rodrigo Mesquita at 2025-07-08T07:40:30-04:00
cleanup: Use BreakpointIds in bytecode gen
Small clean up to use BreakpointId and InternalBreakpointId more
uniformly in bytecode generation rather than using Module + Ix pairs
-
0515cc2f
by Rodrigo Mesquita at 2025-07-08T07:40:30-04:00
ghci: Allocate BreakArrays at link time only
Previously, a BreakArray would be allocated with a slot for every tick
in a module at `mkModBreaks`, in HsToCore. However, this approach has
a few downsides:
- It interleaves interpreter behaviour (allocating arrays for
breakpoints) within the desugarer
- It is inflexible in the sense it is impossible for the bytecode
generator to add "internal" breakpoints that can be triggered at
runtime, because those wouldn't have a source tick. (This is relevant
for our intended implementation plan of step-out in #26042)
- It ties the BreakArray indices to the *tick* indexes, while at runtime
we would rather just have the *info* indexes (currently we have both
because BreakArrays are indexed by the *tick* one).
Paving the way for #26042 and #26064, this commit moves the allocation
of BreakArrays to bytecode-loading time -- akin to what is done for CCS
arrays.
Since a BreakArray is allocated only when bytecode is linked, if a
breakpoint is set (e.g. `:break 10`) before the bytecode is linked,
there will exist no BreakArray to trigger the breakpoint in.
Therefore, the function to allocate break arrays (`allocateBreakArrays`)
is exposed and also used in GHC.Runtime.Eval to allocate a break array
when a breakpoint is set, if it doesn't exist yet (in the linker env).
-
8016561f
by Simon Peyton Jones at 2025-07-08T07:41:13-04:00
Add a test for T26176
-
454cd682
by Simon Peyton Jones at 2025-07-08T07:41:13-04:00
Add test for #14010
This test started to work in GHC 9.6 and has worked since.
This MR just adds a regression test
-
ea2c6673
by Teo Camarasu at 2025-07-08T13:24:43-04:00
Implement user-defined allocation limit handlers
Allocation Limits allow killing a thread if they allocate more than a
user-specified limit.
We extend this feature to allow more versatile behaviour.
- We allow not killing the thread if the limit is exceeded.
- We allow setting a custom handler to be called when the limit is exceeded.
User-specified allocation limit handlers run in a fresh thread and are passed
the ThreadId of the thread that exceeded its limit.
We introduce utility functions for getting and setting the allocation
limits of other threads, so that users can reset the limit of a thread
from a handler. Both of these are somewhat coarse-grained as we are
unaware of the allocations in the current nursery chunk.
We provide several examples of usages in testsuite/tests/rts/T22859.hs
Resolves #22859
-
03e047f9
by Simon Hengel at 2025-07-08T13:25:25-04:00
Fix typo in using.rst
-
67957854
by Ben Gamari at 2025-07-09T09:44:44-04:00
compiler: Import AnnotationWrapper from ghc-internal
Since `GHC.Desugar` exported from `base` has been deprecated.
-
813d99d6
by Ben Gamari at 2025-07-09T09:44:44-04:00
ghc-compact: Eliminate dependency on ghc-prim
-
0ec952a1
by Ben Gamari at 2025-07-09T09:44:44-04:00
ghc-heap: Eliminate dependency on ghc-prim
-
480074c3
by Ben Gamari at 2025-07-09T09:44:44-04:00
ghc-heap: Drop redundant import
-
03455829
by Ben Gamari at 2025-07-09T09:44:45-04:00
ghc-prim: Bump version to 0.13.1
There are no interface changes from 0.13.0 but the implementation now
lives in `ghc-internal`.
-
d315345a
by Ben Gamari at 2025-07-09T09:44:45-04:00
template-haskell: Bump version number to 2.24.0.0
Bumps exceptions submodule.
-
004c800e
by Ben Gamari at 2025-07-09T09:44:45-04:00
Bump GHC version number to 9.14
-
eb1a3816
by Ben Gamari at 2025-07-09T09:44:45-04:00
Bump parsec to 3.1.18.0
Bumps parsec submodule.
-
86f83296
by Ben Gamari at 2025-07-09T09:44:45-04:00
unix: Bump to 2.8.7.0
Bumps unix submodule.
-
89e13998
by Ben Gamari at 2025-07-09T09:44:45-04:00
binary: Bump to 0.8.9.3
Bumps binary submodule.
-
55fff191
by Ben Gamari at 2025-07-09T09:44:45-04:00
Win32: Bump to 2.14.2.0
Bumps Win32 submodule.
-
7dafa40c
by Ben Gamari at 2025-07-09T09:44:45-04:00
base: Bump version to 4.22.0
Bumps various submodules.
-
ef03d8b8
by Rodrigo Mesquita at 2025-07-09T09:45:28-04:00
base: Export displayExceptionWithInfo
This function should be exposed from base following CLC#285
Approved change in CLC#344
Fixes #26058
-
01d3154e
by Wen Kokke at 2025-07-10T17:06:36+01:00
Fix documentation for HEAP_PROF_SAMPLE_STRING
-
ac259c48
by Wen Kokke at 2025-07-10T17:06:38+01:00
Fix documentation for HEAP_PROF_SAMPLE_COST_CENTRE
-
2b4db9ba
by Pi Delport at 2025-07-11T16:40:52-04:00
(Applicative docs typo: missing "one")
-
f707bab4
by Andreas Klebinger at 2025-07-12T14:56:16+01:00
Specialise: Improve specialisation by refactoring interestingDict
This MR addresses #26051, which concerns missed type-class specialisation.
The main payload of the MR is to completely refactor the key function
`interestingDict` in GHC.Core.Opt.Specialise
The main change is that we now also look at the structure of the
dictionary we consider specializing on, rather than only the type.
See the big `Note [Interesting dictionary arguments]`
-
ca7a9d42
by Simon Peyton Jones at 2025-07-12T14:56:16+01:00
Treat tuple dictionaries uniformly; don't unbox them
See `Note [Do not unbox class dictionaries]` in DmdAnal.hs,
sep (DNB1).
This MR reverses the plan in #23398, which suggested a special case to
unbox tuple dictionaries in worker/wrapper. But:
- This was the cause of a pile of complexity in the specialiser (#26158)
- Even with that complexity, specialision was still bad, very bad
See https://gitlab.haskell.org/ghc/ghc/-/issues/19747#note_626297
And it's entirely unnecessary! Specialision works fine without
unboxing tuple dictionaries.
-
be7296c9
by Andreas Klebinger at 2025-07-12T14:56:16+01:00
Remove complex special case from the type-class specialiser
There was a pretty tricky special case in Specialise which is no
longer necessary.
* Historical Note [Floating dictionaries out of cases]
* #26158
* #19747 https://gitlab.haskell.org/ghc/ghc/-/issues/19747#note_626297
This MR removes it. Hooray.
-
4acf3a86
by Ben Gamari at 2025-07-15T05:46:32-04:00
configure: bump version to 9.15
-
45efaf71
by Teo Camarasu at 2025-07-15T05:47:13-04:00
rts/nonmovingGC: remove n_free
We remove the nonmovingHeap.n_free variable.
We wanted this to track the length of nonmovingHeap.free.
But this isn't possible to do atomically.
When this isn't accurate we can get a segfault by going past the end of
the list.
Instead, we just count the length of the list when we grab it in
nonmovingPruneFreeSegment.
Resolves #26186
-
c635f164
by Ben Gamari at 2025-07-15T14:05:54-04:00
configure: Drop probing of ld.gold
As noted in #25716, `gold` has been dropped from binutils-2.44.
Fixes #25716.
Metric Increase:
size_hello_artifact_gzip
size_hello_unicode_gzip
ghc_prim_so
-
637bb538
by Ben Gamari at 2025-07-15T14:05:55-04:00
testsuite/recomp015: Ignore stderr
This is necessary since ld.bfd complains
that we don't have a .note.GNU-stack section,
potentially resulting in an executable stack.
-
d3cd4ec8
by Wen Kokke at 2025-07-15T14:06:39-04:00
Fix documentation for heap profile ID
-
73082769
by Ben Gamari at 2025-07-15T16:56:38-04:00
Bump win32-tarballs to v0.9
-
3b63b254
by Ben Gamari at 2025-07-15T16:56:39-04:00
rts/LoadArchive: Handle null terminated string tables
As of `llvm-ar` now emits filename tables terminated with null
characters instead of the usual POSIX `/\n` sequence.
Fixes #26150.
-
195f6527
by Tamar Christina at 2025-07-15T16:56:39-04:00
rts: rename label so name doesn't conflict with param
-
63373b95
by Tamar Christina at 2025-07-15T16:56:39-04:00
rts: Handle API set symbol versioning conflicts
-
48e9aa3e
by Tamar Christina at 2025-07-15T16:56:39-04:00
rts: Mark API set symbols as HIDDEN and correct symbol type
-
959e827a
by Tamar Christina at 2025-07-15T16:56:39-04:00
rts: Implement WEAK EXTERNAL undef redirection by target symbol name
-
65f19293
by Ben Gamari at 2025-07-15T16:56:39-04:00
rts/LoadArchive: Handle string table entries terminated with /
llvm-ar appears to terminate string table entries with `/\n` [1]. This
matters in the case of thin archives, since the filename is used. In the
past this worked since `llvm-ar` would produce archives with "small"
filenames when possible. However, now it appears to always use the
string table.
[1] https://github.com/llvm/llvm-project/blob/bfb686bb5ba503e9386dc899e1ebbe2488e6a0a8/llvm/lib/Object/ArchiveWriter.cpp#L314
-
9cbb3ef5
by Ben Gamari at 2025-07-15T16:56:39-04:00
testsuite: Mark T12497 as fixed
Thanks to the LLVM toolchain update.
Closes #22694.
-
2854407e
by Ben Gamari at 2025-07-15T16:56:39-04:00
testsuite: Accept new output of T11223_link_order_a_b_2_fail on Windows
The archive member number changed due to the fact that llvm-ar now uses a
string table.
-
28439593
by Ben Gamari at 2025-07-15T16:56:39-04:00
rts/linker/PEi386: Implement IMAGE_REL_AMD64_SECREL
This appears to now be used by libc++ as distributed by msys2.
-
2b053755
by Tamar Christina at 2025-07-15T16:56:39-04:00
rts: Cleanup merge resolution residue in lookupSymbolInDLL_PEi386 and make safe without dependent
-
e8acd2e7
by Wen Kokke at 2025-07-16T08:37:04-04:00
Remove the `profile_id` parameter from various RTS functions.
Various RTS functions took a `profile_id` parameter, intended to be used to
distinguish parallel heap profile breakdowns (e.g., `-hT` and `-hi`). However,
this feature was never implemented and the `profile_id` parameter was set to 0
throughout the RTS. This commit removes the parameter but leaves the hardcoded
profile ID in the functions that emit the encoded eventlog events as to not
change the protocol.
The affected functions are `traceHeapProfBegin`, `postHeapProfBegin`,
`traceHeapProfSampleString`, `postHeapProfSampleString`,
`traceHeapProfSampleCostCentre`, and `postHeapProfSampleCostCentre`.
-
76d392a2
by Wen Kokke at 2025-07-16T08:37:04-04:00
Make `traceHeapProfBegin` an init event.
-
bbaa44a7
by Peng Fan at 2025-07-16T16:50:42-04:00
NCG/LA64: Support finer-grained DBAR hints
For LA664 and newer uarchs, they have made finer granularity hints
available:
Bit4: ordering or completion (0: completion, 1: ordering)
Bit3: barrier for previous read (0: true, 1: false)
Bit2: barrier for previous write (0: true, 1: false)
Bit1: barrier for succeeding read (0: true, 1: false)
Bit0: barrier for succeeding write (0: true, 1: false)
And not affect the existing models because other hints are treated
as 'dbar 0' there.
-
7da86e16
by Andreas Klebinger at 2025-07-16T16:51:25-04:00
Disable -fprof-late-overloaded-calls for join points.
Currently GHC considers cost centres as destructive to
join contexts. Or in other words this is not considered valid:
join f x = ...
in
... -> scc<tick> jmp
This makes the functionality of `-fprof-late-overloaded-calls` not feasible
for join points in general. We used to try to work around this by putting the
ticks on the rhs of the join point rather than around the jump. However beyond
the loss of accuracy this was broken for recursive join points as we ended up
with something like:
rec-join f x = scc<tick> ... jmp f x
Which similarly is not valid as the tick once again destroys the tail call.
One might think we could limit ourselves to non-recursive tail calls and do
something clever like:
join f x = scc<tick> ...
in ... jmp f x
And sometimes this works! But sometimes the full rhs would look something like:
join g x = ....
join f x = scc<tick> ... -> jmp g x
Which, would again no longer be valid. I believe in the long run we can make
cost centre ticks non-destructive to join points. Or we could keep track of
where we are/are not allowed to insert a cost centre. But in the short term I will
simply disable the annotation of join calls under this flag.
-
7ee22fd5
by ARATA Mizuki at 2025-07-17T06:05:30-04:00
x86 NCG: Better lowering for shuffleFloatX4# and shuffleDoubleX2#
The new implementation
* make use of specialized instructions like (V)UNPCK{L,H}{PS,PD}, and
* do not require -mavx.
Close #26096
Co-authored-by: sheaf <sam.derbyshire@gmail.com>
-
c6cd2da1
by Jappie Klooster at 2025-07-17T06:06:20-04:00
Update interact docs to explain about buffering
We need to tell the user to set to the
appropriate buffer format.
Otherwise, this function may get randomly stuck,
or just behave confusingly.
issue: https://gitlab.haskell.org/ghc/ghc/-/issues/26131
NB, I'm running this with cabal *NOT* ghci. ghci messes with buffering anyway.
```haskell
interaction :: String -> String
interaction "jappie" = "hi"
interaction "jakob" = "hello"
interaction x = "unkown input: " <> x
main :: IO ()
main = interact interaction
```
so in my input (prefixed by `>`) I get:
```
> jappie
unkown input: jappie
```
we confirmed later this was due to lack of \n matching.
Anyway movnig on to more unexpected stuff:
```haskell
main :: IO ()
main = do
interact (concatMap interaction . lines)
```
get's stuck forever.
actually `^D` (ctrl+d) unstucks it and runs all input as expected.
for example you can get:
```
> sdfkds
> fakdsf
unkown input: sdfkdsunkown input: fakdsf
```
This program works!
```haskell
interaction :: String -> String
interaction "jappie" = "hi \n"
interaction "jakob" = "hello \n"
interaction x = "unkown input: " <> x <> "\n"
main :: IO ()
main = do
interact (concatMap interaction . lines)
```
the reason is that linebuffering is set for both in and output by default.
so lines eats the input lines, and all the \n postfixes make sure the buffer
is put out.
-
9fa590a6
by Zubin Duggal at 2025-07-17T06:07:03-04:00
fetch_gitlab: Ensure we copy users_guide.pdf and Haddock.pdf to the release docs directory
Fixes #24093
-
cc650b4b
by Andrew Lelechenko at 2025-07-17T12:30:24-04:00
Add Data.List.NonEmpty.mapMaybe
As per https://github.com/haskell/core-libraries-committee/issues/337
-
360fa82c
by Duncan Coutts at 2025-07-17T12:31:14-04:00
base: Deprecate GHC.Weak.Finalize.runFinalizerBatch
https://github.com/haskell/core-libraries-committee/issues/342
-
f4e8466c
by Alan Zimmerman at 2025-07-17T12:31:55-04:00
EPA: Update exact printing based on GHC 9.14 tests
As a result of migrating the GHC ghc-9.14 branch tests to
ghc-exactprint in
https://github.com/alanz/ghc-exactprint/tree/ghc-9.14, a couple of
discrepancies were picked up
- The opening paren for a DefaultDecl was printed in the wrong place
- The import declaration level specifiers were not printed.
This commit adds those fixes, and some tests for them.
The tests brought to light that the ImportDecl ppr instance had not
been updated for level specifiers, so it updates that too.
-
8b731e3c
by Matthew Pickering at 2025-07-21T13:36:43-04:00
level imports: Fix infinite loop with cyclic module imports
I didn't anticipate that downsweep would run before we checked for
cyclic imports. Therefore we need to use the reachability function which
handles cyclic graphs.
Fixes #26087
-
d751a9f1
by Pierre Thierry at 2025-07-21T13:37:28-04:00
Fix documentation about deriving from generics
-
f8d9d016
by Andrew Lelechenko at 2025-07-22T21:13:28-04:00
Fix issues with toRational for types capable to represent infinite and not-a-number values
This commit fixes all of the following pitfalls:
> toRational (read "Infinity" :: Double)
179769313486231590772930519078902473361797697894230657273430081157732675805500963132708477322407536021120113879871393357658789768814416622492847430639474124377767893424865485276302219601246094119453082952085005768838150682342462881473913110540827237163350510684586298239947245938479716304835356329624224137216 % 1
> toRational (read "NaN" :: Double)
269653970229347386159395778618353710042696546841345985910145121736599013708251444699062715983611304031680170819807090036488184653221624933739271145959211186566651840137298227914453329401869141179179624428127508653257226023513694322210869665811240855745025766026879447359920868907719574457253034494436336205824 % 1
> realToFrac (read "NaN" :: Double) -- With -O0
Infinity
> realToFrac (read "NaN" :: Double) -- With -O1
NaN
> realToFrac (read "NaN" :: Double) :: CDouble
Infinity
> realToFrac (read "NaN" :: CDouble) :: Double
Infinity
Implements https://github.com/haskell/core-libraries-committee/issues/338
-
5dabc718
by Zubin Duggal at 2025-07-22T21:14:10-04:00
haddock: Don't warn about missing link destinations for derived names.
Fixes #26114
-
9c3a0937
by Matthew Pickering at 2025-07-22T21:14:52-04:00
template haskell: use a precise condition when implicitly lifting
Implicit lifting corrects a level error by replacing references to `x`
with `$(lift x)`, therefore you can use a level `n` binding at level `n
+ 1`, if it can be lifted.
Therefore, we now have a precise check that the use level is 1 more than
the bind level.
Before this bug was not observable as you only had 0 and 1 contexts but
it is easily evident when using explicit level imports.
Fixes #26088
-
5144b22f
by Andreas Klebinger at 2025-07-22T21:15:34-04:00
Add since tag and more docs for do-clever-arg-eta-expansion
Fixes #26113
-
c865623b
by Andreas Klebinger at 2025-07-22T21:15:34-04:00
Add since tag for -fexpose-overloaded-unfoldings
Fixes #26112
-
49a44ab7
by Simon Hengel at 2025-07-23T17:59:55+07:00
Refactor GHC.Driver.Errors.printMessages
-
84711c39
by Simon Hengel at 2025-07-23T18:27:34+07:00
Respect `-fdiagnostics-as-json` for error messages from pre-processors
(fixes #25480)
-
d046b5ab
by Simon Hengel at 2025-07-24T06:12:05-04:00
Include the rendered message in -fdiagnostics-as-json output
This implements #26173.
-
d2b89603
by Ben Gamari at 2025-07-24T06:12:47-04:00
rts/Interpreter: Factor out ctoi tuple info tables into data
Instead of a massive case let's put this into data which we can reuse
elsewhere.
-
4bc78496
by Sebastian Graf at 2025-07-24T16:19:34-04:00
CprAnal: Detect recursive newtypes (#25944)
While `cprTransformDataConWork` handles recursive data con workers, it
did not detect the case when a newtype is responsible for the recursion.
This is now detected in the `Cast` case of `cprAnal`.
The same reproducer made it clear that `isRecDataCon` lacked congruent
handling for `AppTy` and `CastTy`, now fixed.
Furthermore, the new repro case T25944 triggered this bug via an
infinite loop in `cprFix`, caused by the infelicity in `isRecDataCon`.
While it should be much less likely to trigger such an infinite loop now
that `isRecDataCon` has been fixed, I made sure to abort the loop after
10 iterations and emitting a warning instead.
Fixes #25944.
-
0a583689
by Sylvain Henry at 2025-07-24T16:20:26-04:00
STM: don't create a transaction in the rhs of catchRetry# (#26028)
We don't need to create a transaction for the rhs of (catchRetry#)
because contrary to the lhs we don't need to abort it on retry. Moreover
it is particularly harmful if we have code such as (#26028):
let cN = readTVar vN >> retry
tree = c1 `orElse` (c2 `orElse` (c3 `orElse` ...))
atomically tree
Because it will stack transactions for the rhss and the read-sets of all
the transactions will be iteratively merged in O(n^2) after the
execution of the most nested retry.
-
a49eca26
by Simon Peyton Jones at 2025-07-25T09:49:58+01:00
Renaming around predicate types
.. we were (as it turned out) abstracting over
type-class selectors in SPECIALISATION rules!
Wibble isEqPred
-
f80375dd
by Simon Peyton Jones at 2025-07-25T09:49:58+01:00
Refactor of Specialise.hs
This patch just tidies up `specHeader` a bit, removing one
of its many results, and adding some comments.
No change in behaviour.
Also add a few more `HasDebugCallStack` contexts.
-
1bd12371
by Simon Peyton Jones at 2025-07-25T09:49:58+01:00
Improve treatment of SPECIALISE pragmas -- again!
This MR does another major refactor of the way that SPECIALISE
pragmas work, to fix #26115, #26116, #26117.
* We now /always/ solve forall-constraints in an all-or-nothing way.
See Note [Solving a Wanted forall-constraint] in GHC.Tc.Solver.Solve
This means we might have unsolved quantified constraints, which need
to be reported. See `inert_insts` in `getUnsolvedInerts`.
* I refactored the short-cut solver for type classes to work by
recursively calling the solver rather than by having a little baby
solver that kept being not clever enough.
See Note [Shortcut solving] in GHC.Tc.Solver.Dict
* I totally rewrote the desugaring of SPECIALISE pragmas, again.
The new story is in Note [Desugaring new-form SPECIALISE pragmas]
in GHC.HsToCore.Binds
Both old-form and new-form SPECIALISE pragmas now route through the same
function `dsSpec_help`. The tricky function `decomposeRuleLhs` is now used only
for user-written RULES, not for SPECIALISE pragmas.
* I improved `solveOneFromTheOther` to account for rewriter sets. Previously
it would solve a non-rewritten dict from a rewritten one. For equalities
we were already dealing with this, in
Some incidental refactoring
* A small refactor: `ebv_tcvs` in `EvBindsBar` now has a list of coercions, rather
than a set of tyvars. We just delay taking the free vars.
* GHC.Core.FVs.exprFVs now returns /all/ free vars.
Use `exprLocalFVs` for Local vars.
Reason: I wanted another variant for /evidence/ variables.
* Ues `EvId` in preference to `EvVar`. (Evidence variables are always Ids.)
Rename `isEvVar` to `isEvId`.
* I moved `inert_safehask` out of `InertCans` and into `InertSet` where it
more properly belongs.
Compiler-perf changes:
* There was a palpable bug (#26117) which this MR fixes in
newWantedEvVar, which bypassed all the subtle overlapping-Given
and shortcutting logic. (See the new `newWantedEvVar`.) Fixing this
but leads to extra dictionary bindings; they are optimised away quickly
but they made CoOpt_Read allocate 3.6% more.
* Hpapily T15164 improves.
* The net compiler-allocation change is 0.0%
Metric Decrease:
T15164
Metric Increase:
CoOpt_Read
T12425
-
953fd8f1
by Simon Peyton Jones at 2025-07-25T09:49:58+01:00
Solve forall-constraints immediately, or not at all
This MR refactors the constraint solver to solve forall-constraints immediately,
rather than emitting an implication constraint to be solved later.
The most immediate motivation was that when solving quantified constraints
in SPECIALISE pragmas, we really really don't want to leave behind half-
solved implications. Also it's in tune with the approach of the new
short-cut solver, which recursively invokes the solver.
It /also/ saves quite a bit of plumbing; e.g
- The `wl_implics` field of `WorkList` is gone,
- The types of `solveSimpleWanteds` and friends are simplified.
- An EvFun contains binding, rather than an EvBindsVar ref-cell that
will in the future contain bindings. That makes `evVarsOfTerm`
simpler. Much nicer.
It also improves error messages a bit.
All described in Note [Solving a Wanted forall-constraint] in
GHC.Tc.Solver.Solve.
One tiresome point: in the tricky case of `inferConstraintsCoerceBased`
we make a forall-constraint. This we /do/ want to partially solve, so
we can infer a suitable context. (I'd be quite happy to force the user to
write a context, bt I don't want to change behavior.) So we want to generate
an /implication/ constraint in `emitPredSpecConstraints` rather than a
/forall-constraint/ as we were doing before. Discussed in (WFA3) of
the above Note.
Incidental refactoring
* `GHC.Tc.Deriv.Infer.inferConstraints` was consulting the state monad for
the DerivEnv that the caller had just consulted. Nicer to pass it as an
argument I think, so I have done that. No change in behaviour.
-
6921ab42
by Simon Peyton Jones at 2025-07-25T09:49:58+01:00
Remove duplicated code in Ast.hs for evTermFreeVars
This is just a tidy up.
-
1165f587
by Simon Peyton Jones at 2025-07-25T09:49:58+01:00
Small tc-tracing changes only
-
0776ffe0
by Simon Hengel at 2025-07-26T04:54:20-04:00
Respect `-fdiagnostics-as-json` for core diagnostics (see #24113)
-
cc1116e0
by Andrew Lelechenko at 2025-07-26T04:55:01-04:00
docs: add since pragma to Data.List.NonEmpty.mapMaybe
-
ee2dc248
by Simon Hengel at 2025-07-31T06:25:35-04:00
Update comments on `OptKind` to reflect the code reality
-
b029633a
by Wen Kokke at 2025-07-31T06:26:21-04:00
rts: Disable --eventlog-flush-interval unless compiled with -threaded.
This commit fixes issue #26222:
Using --eventlog-flush-interval with the non-threaded RTS leads to eventlog corruption.
https://gitlab.haskell.org/ghc/ghc/-/issues/26222
This commit makes three changes when code is compiled against the non-threaded RTS:
1. It disables the --eventlog-flush-interval flag.
2. It disables the documentation for the --eventlog-flush-interval flag.
3. It disables the relevant state from RtsConfig and code from Timer.
4. It updates the entry for --eventlog-flush-interval in the users guide.
-
31159f1d
by Wen Kokke at 2025-07-31T06:26:21-04:00
rts: Split T20006 into tests with and without -threaded
-
618687ef
by Simon Hengel at 2025-07-31T06:27:03-04:00
docs/users_guide/win32-dlls.rst: Remove references to `readline`
-
083e40f1
by Rodrigo Mesquita at 2025-08-01T04:38:23-04:00
debugger: Uniquely identify breakpoints by internal id
Since b85b11994e0130ff2401dd4bbdf52330e0bcf776 (support inlining
breakpoints), a breakpoint has been identified at runtime by *two* pairs
of <module,index>.
- The first, aka a 'BreakpointId', uniquely identifies a breakpoint in
the source of a module by using the Tick index. A Tick index can index
into ModBreaks.modBreaks_xxx to fetch source-level information about
where that tick originated.
- When a user specifies e.g. a line breakpoint using :break, we'll reverse
engineer what a Tick index for that line
- We update the `BreakArray` of that module (got from the
LoaderState) at that tick index to `breakOn`.
- A BCO we can stop at is headed by a BRK_FUN instruction. This
instruction stores in an operand the `tick index` it is associated
to. We look it up in the associated `BreakArray` (also an operand)
and check wheter it was set to `breakOn`.
- The second, aka the `ibi_info_mod` + `ibi_info_ix` of the
`InternalBreakpointId`, uniquely index into the `imodBreaks_breakInfo`
-- the information we gathered during code generation about the
existing breakpoint *ocurrences*.
- Note that with optimisation there may be many occurrences of the
same source-tick-breakpoint across different modules. The
`ibi_info_ix` is unique per occurrence, but the `bi_tick_ix` may be
shared. See Note [Breakpoint identifiers] about this.
- Note that besides the tick ids, info ids are also stored in
`BRK_FUN` so the break handler can refer to the associated
`CgBreakInfo`.
In light of that, the driving changes come from the desire to have the
info_id uniquely identify the breakpoint at runtime, and the source tick
id being derived from it:
- An InternalBreakpointId should uniquely identify a breakpoint just
from the code-generation identifiers of `ibi_info_ix` and `ibi_info_mod`.
So we drop `ibi_tick_mod` and `ibi_tick_ix`.
- A BRK_FUN instruction need only record the "internal breakpoint id",
not the tick-level id.
So we drop the tick mod and tick index operands.
- A BreakArray should be indexed by InternalBreakpointId rather than
BreakpointId
That means we need to do some more work when setting a breakpoint.
Specifically, we need to figure out the internal ids (occurrences of a
breakpoint) from the source-level BreakpointId we want to set the
breakpoint at (recall :break refers to breaks at the source level).
Besides this change being an improvement to the handling of breakpoints
(it's clearer to have a single unique identifier than two competing
ones), it unlocks the possibility of generating "internal" breakpoints
during Cg (needed for #26042).
It should also be easier to introduce multi-threaded-aware `BreakArrays`
following this change (needed for #26064).
Se also the new Note [ModBreaks vs InternalModBreaks]
On i386-linux:
-------------------------
Metric Decrease:
interpreter_steplocal
-------------------------
-
bf03bbaa
by Simon Hengel at 2025-08-01T04:39:05-04:00
Don't use MCDiagnostic for `ghcExit`
This changes the error message of `ghcExit` from
```
<no location info>: error:
Compilation had errors
```
to
```
Compilation had errors
```
-
a889ec75
by Simon Hengel at 2025-08-01T04:39:05-04:00
Respect `-fdiagnostics-as-json` for driver diagnostics (see #24113)
-
81577fe7
by Ben Gamari at 2025-08-02T04:29:39-04:00
configure: Allow override of CrossCompiling
As noted in #26236, the current inference logic is a bit simplistic. In
particular, there are many cases (e.g. building for a new libc) where
the target and host triples may differ yet we are still able to run the
produced artifacts as native code.
Closes #26236.
-
01136779
by Andreas Klebinger at 2025-08-02T04:30:20-04:00
rts: Support COFF BigObj files in archives.
-
1f9e4f54
by Stephen Morgan at 2025-08-03T15:14:08+10:00
refactor: Modify Data.List.sortOn to use (>) instead of compare. (#26184)
This lets a more efficient (>) operation be used if one exists.
This is technically a breaking change for malformed Ord instances, where
x > y is not equivalent to compare x y == GT.
Discussed by the CLC in issue #332: https://github.com/haskell/core-libraries-committee/issues/332
-
4f6bc9cf
by fendor at 2025-08-04T17:50:06-04:00
Revert "base: Expose Backtraces constructor and fields"
This reverts commit 17db44c5b32fff82ea988fa4f1a233d1a27bdf57.
-
bcdec657
by Zubin Duggal at 2025-08-05T10:37:29+05:30
compiler: Export a version of `newNameCache` that is not prone to footguns.
`newNameCache` must be initialized with both a non-"reserved" unique tag, as well
as a list of known key names. Failing to do so results in hard to debug unique conflicts.
It is difficult for API users to tell which unique tags are safe to use. So instead of leaving
this up to the user to decide, we now export a version of `newNameCache` which uses a guaranteed
non-reserved unique tag. In fact, this is now the way the unique tag is initialized for all invocations
of the compiler.
The original version of `newNameCache` is now exported as `newNameCache'` for advanced users.
We also deprecate `initNameCache` as it is also prone to footguns and is completely subsumed in
functionality by `newNameCache` and `newNameCache'`.
Fixes #26135 and #26055
-
57d3b4a8
by Andrew Lelechenko at 2025-08-05T18:36:31-04:00
hadrian: bump Stackage snapshot to LTS 24.2 / GHC 9.10.2
In line with #25693 we should use GHC 9.10 as a boot compiler,
while Hadrian stack.yaml was stuck on GHC 9.6.
-
c2a78cea
by Peng Fan at 2025-08-05T18:37:27-04:00
NCG/LA64: implement atomic write with finer-grained DBAR hints
Signed-off-by: Peng Fan <fanpeng@loongson.cn>
-
95231c8e
by Teo Camarasu at 2025-08-06T08:35:58-04:00
CODEOWNERS: add CLC as codeowner of base
We also remove hvr, since I think he is no longer active
-
77df0ded
by Andrew Lelechenko at 2025-08-06T08:36:39-04:00
Bump submodule text to 2.1.3
-
8af260d0
by Nikolaos Chatzikonstantinou at 2025-08-06T08:37:23-04:00
docs: fix internal import in getopt examples
This external-facing doc example shouldn't mention GHC internals when
using 'fromMaybe'.
-
69cc16ca
by Marc Scholten at 2025-08-06T15:51:28-04:00
README: Add note on ghc.nix
-
93a2f450
by Daniel Díaz at 2025-08-06T15:52:14-04:00
Link to the "Strict Bindings" docs from the linear types docs
Strict Bidings are relevant for the kinds of multiplicity annotations
linear lets support.
-
246b7853
by Matthew Pickering at 2025-08-07T06:58:30-04:00
level imports: Check the level of exported identifiers
The level imports specification states that exported identifiers have to
be at level 0. This patch adds the requird level checks that all
explicitly mentioned identifiers occur at level 0.
For implicit export specifications (T(..) and module B), only level 0
identifiers are selected for re-export.
ghc-proposal: https://github.com/ghc-proposals/ghc-proposals/pull/705
Fixes #26090
-
358bc4fc
by fendor at 2025-08-07T06:59:12-04:00
Bump GHC on darwin CI to 9.10.1
-
1903ae35
by Matthew Pickering at 2025-08-07T12:21:10+01:00
ipe: Place strings and metadata into specific .ipe section
By placing the .ipe metadata into a specific section it can be stripped
from the final binary if desired.
```
objcopy --remove-section .ipe <binary>
upx <binary>
```
Towards #21766
-
c80dd91c
by Matthew Pickering at 2025-08-07T12:22:42+01:00
ipe: Place magic word at the start of entries in the .ipe section
The magic word "IPE\nIPE\n" is placed at the start of .ipe sections,
then if the section is stripped, we can check whether the section starts
with the magic word or not to determine whether there is metadata
present or not.
Towards #21766
-
cab42666
by Matthew Pickering at 2025-08-07T12:22:42+01:00
ipe: Use stable IDs for IPE entries
IPEs have historically been indexed and reported by their address.
This makes it impossible to compare profiles between runs, since the
addresses may change (due to ASLR) and also makes it tricky to separate
out the IPE map from the binary.
This small patch adds a stable identifier for each IPE entry.
The stable identifier is a single 64 bit word. The high-bits are a
per-module identifier and the low bits identify which entry in each
module.
1. When a node is added into the IPE buffer it is assigned a unique
identifier from an incrementing global counter.
2. Each entry already has an index by it's position in the
`IpeBufferListNode`.
The two are combined together by the `IPE_ENTRY_KEY` macro.
Info table profiling uses the stable identifier rather than the address
of the info table.
The benefits of this change are:
* Profiles from different runs can be easily compared
* The metadata can be extracted from the binary (via the eventlog for
example) and then stripped from the executable.
Fixes #21766
-
2860a9a5
by Simon Peyton Jones at 2025-08-07T20:29:18-04:00
In TcSShortCut, typechecker plugins should get empty Givens
Solving in TcShortCut mode means /ignoring the Givens/. So we
should not pass them to typechecker plugins!
Fixes #26258.
This is a fixup to the earlier MR:
commit 1bd12371feacc52394a0e660ef9349f9e8ee1c06
Author: Simon Peyton Jones <simon.peytonjones@gmail.com>
Date: Mon Jul 21 10:04:49 2025 +0100
Improve treatment of SPECIALISE pragmas -- again!
-
2157db2d
by sterni at 2025-08-08T15:32:39-04:00
hadrian: enable terminfo if --with-curses-* flags are given
The GHC make build system used to support WITH_TERMINFO in ghc.mk which
allowed controlling whether to build GHC with terminfo or not. hadrian
has replaced this with a system where this is effectively controlled by
the cross-compiling setting (the default WITH_TERMINFO value was bassed
on CrossCompiling, iirc).
This behavior is undesireable in some cases and there is not really a
good way to work around it. Especially for downstream packagers,
modifying this via UserSettings is not really feasible since such a
source file has to be kept in sync with Settings/Default.hs manually
since it can't import Settings.Default or any predefined Flavour
definitions.
To avoid having to add a new setting to cfg/system.config and/or a new
configure flag (though I'm happy to implement both if required), I've
chosen to take --with-curses-* being set explicitly as an indication
that the user wants to have terminfo enabled. This would work for
Nixpkgs which sets these flags [1] as well as haskell.nix [2] (which
goes to some extreme measures [3] [4] to force terminfo in all scenarios).
In general, I'm an advocate for making the GHC build be the same for
native and cross insofar it is possible since it makes packaging GHC and
Haskell related things while still supporting cross much less
compilicated. A more minimal GHC with reduced dependencies should
probably be a specific flavor, not the default.
Partially addresses #26288 by forcing terminfo to be built if the user
explicitly passes configure flags related to it. However, it isn't built
by default when cross-compiling yet nor is there an explicit way to
control the package being built.
[1]: https://github.com/NixOS/nixpkgs/blob/3a7266fcefcb9ce353df49ba3f292d06443760bb/pkgs/development/compilers/ghc/common-hadrian.nix#L513-L515
[2]: https://github.com/input-output-hk/haskell.nix/blob/6eaafcdf04bab7be745d1aa4f74d2cc85700042b/compiler/ghc/default.nix#L185
[3]: https://github.com/input-output-hk/haskell.nix/blob/6eaafcdf04bab7be745d1aa4f74d2cc85700042b/compiler/ghc/default.nix#L678-L682
[4]: https://github.com/input-output-hk/haskell.nix/blob/6eaafcdf04bab7be745d1aa4f74d2cc85700042b/compiler/ghc/default.nix#L772-L773
-
b3c31488
by David Feuer at 2025-08-08T15:33:21-04:00
Add default QuasiQuoters
Add `defaultQuasiQuoter` and `namedDefaultQuasiQuoter` to make it easier
to write `QuasiQuoters` that give helpful error messages when they're
used in inappropriate contexts.
Closes #24434.
-
03555ed8
by Sylvain Henry at 2025-08-10T22:20:57-04:00
Handle non-fractional CmmFloats in Cmm's CBE (#26229)
Since f8d9d016305be355f518c141f6c6d4826f2de9a2, toRational for Float and
Double converts float's infinity and NaN into Rational's infinity and
NaN (respectively 1%0 and 0%0).
Cmm CommonBlockEliminator hashing function needs to take these values
into account as they can appear as literals now. See added testcase.
-
6c956af3
by J. Ryan Stinnett at 2025-08-10T22:21:42-04:00
Fix extensions list in `DoAndIfThenElse` docs
-
6dc420b1
by J. Ryan Stinnett at 2025-08-10T22:21:42-04:00
Document status of `RelaxedPolyRec` extension
This adds a brief extension page explaining the status of the
`RelaxedPolyRec` extension. The behaviour of this mode is already
explained elsewhere, so this page is mainly for completeness so that
various lists of extensions have somewhere to point to for this flag.
Fixes #18630
-
18036d52
by Simon Peyton Jones at 2025-08-11T11:31:20-04:00
Take more care in zonkEqTypes on AppTy/AppTy
This patch fixes #26256.
See Note [zonkEqTypes and the PKTI] in GHC.Tc.Solver.Equality
-
c8d76a29
by Zubin Duggal at 2025-08-11T11:32:02-04:00
ci: upgrade bootstrap compiler on windows to 9.10.1
-
34fc50c1
by Ben Gamari at 2025-08-11T13:36:25-04:00
Kill IOPort#
This type is unnecessary, having been superceded by `MVar` and a rework
of WinIO's blocking logic.
See #20947.
See https://github.com/haskell/core-libraries-committee/issues/213.
-
56b32c5a
by sheaf at 2025-08-12T10:00:19-04:00
Improve deep subsumption
This commit improves the DeepSubsumption sub-typing implementation
in GHC.Tc.Utils.Unify.tc_sub_type_deep by being less eager to fall back
to unification.
For example, we now are properly able to prove the subtyping relationship
((∀ a. a->a) -> Int) -> Bool <= β[tau] Bool
for an unfilled metavariable β. In this case (with an AppTy on the right),
we used to fall back to unification. No longer: now, given that the LHS
is a FunTy and that the RHS is a deep rho type (does not need any instantiation),
we try to make the RHS into a FunTy, viz.
β := (->) γ
We can then continue using covariance & contravariance of the function
arrow, which allows us to prove the subtyping relationship, instead of
trying to unify which would cause us to error out with:
Couldn't match expected type ‘β’ with actual type ‘(->) ((∀ a. a -> a) -> Int)
See Note [FunTy vs non-FunTy case in tc_sub_type_deep] in GHC.Tc.Utils.Unify.
The other main improvement in this patch concerns type inference.
The main subsumption logic happens (before & after this patch) in
GHC.Tc.Gen.App.checkResultTy. However, before this patch, all of the
DeepSubsumption logic only kicked in in 'check' mode, not in 'infer' mode.
This patch adds deep instantiation in the 'infer' mode of checkResultTy
when we are doing deep subsumption, which allows us to accept programs
such as:
f :: Int -> (forall a. a->a)
g :: Int -> Bool -> Bool
test1 b =
case b of
True -> f
False -> g
test2 b =
case b of
True -> g
False -> f
See Note [Deeply instantiate in checkResultTy when inferring].
Finally, we add representation-polymorphism checks to ensure that the
lambda abstractions we introduce when doing subsumption obey the
representation polymorphism invariants of Note [Representation polymorphism invariants]
in GHC.Core. See Note [FunTy vs FunTy case in tc_sub_type_deep].
This is accompanied by a courtesy change to `(<.>) :: HsWrapper -> HsWrapper -> HsWrapper`,
adding the equation:
WpCast c1 <.> WpCast c2 = WpCast (c1 `mkTransCo` c2)
This is useful because mkWpFun does not introduce an eta-expansion when
both of the argument & result wrappers are casts; so this change allows
us to avoid introducing lambda abstractions when casts suffice.
Fixes #26225
-
d175aff8
by Sylvain Henry at 2025-08-12T10:01:31-04:00
Add regression test for #18619
-
a3983a26
by Sylvain Henry at 2025-08-12T10:02:20-04:00
RTS: remove some TSAN annotations (#20464)
Use RELAXED_LOAD_ALWAYS macro instead.
-
0434af81
by Ben Gamari at 2025-08-12T10:03:02-04:00
Bump time submodule to 1.15
Also required bumps of Cabal, directory, and hpc.
-
62899117
by Florian Ragwitz at 2025-08-13T21:01:34-04:00
Extend record-selector usage ticking to all binds using a record field
This extends the previous handling of ticking for RecordWildCards and
NamedFieldPuns to all var bindings that involve record selectors.
Note that certain patterns such as `Foo{foo = 42}` will currently not tick the
`foo` selector, as ticking is triggered by `HsVar`s.
Closes #26191.
-
b37b3af7
by Florian Ragwitz at 2025-08-13T21:01:34-04:00
Add release notes for 9.16.1 and move description of latest HPC changes there.
-
a5e4b7d9
by Ben Gamari at 2025-08-13T21:02:18-04:00
rts: Clarify rationale for undefined atomic wrappers
Since c06e3f46d24ef69f3a3d794f5f604cb8c2a40cbc the RTS has declared
various atomic operation wrappers defined by ghc-internal as undefined.
While the rationale for this isn't clear from the commit message, I
believe that this is necessary due to the unregisterised backend.
Specifically, the code generator will reference these symbols when
compiling RTS Cmm sources.
-
50842f83
by Andreas Klebinger at 2025-08-13T21:03:01-04:00
Make unexpected LLVM versions a warning rather than an error.
Typically a newer LLVM version *will* work so erroring out if
a user uses a newer LLVM version is too aggressive.
Fixes #25915
-
c91e2650
by fendor at 2025-08-13T21:03:43-04:00
Store `StackTrace` and `StackSnapshot` in `Backtraces`
Instead of decoding the stack traces when collecting the `Backtraces`,
defer this decoding until actually showing the `Backtraces`.
This allows users to customise how `Backtraces` are displayed by
using a custom implementation of `displayExceptionWithInfo`, overwriting
the default implementation for `Backtraces` (`displayBacktraces`).
-
dee28cdd
by fendor at 2025-08-13T21:03:43-04:00
Allow users to customise the collection of exception annotations
Add a global `CollectExceptionAnnotationMechanism` which determines how
`ExceptionAnnotation`s are collected upon throwing an `Exception`.
This API is exposed via `ghc-experimental`.
By overriding how we collect `Backtraces`, we can control how the
`Backtraces` are displayed to the user by newtyping `Backtraces` and
giving a different instance for `ExceptionAnnotation`.
A concrete use-case for this feature is allowing us to experiment with
alternative stack decoders, without having to modify `base`, which take
additional information from the stack frames.
This commit does not modify how `Backtraces` are currently
collected or displayed.
-
66024722
by fendor at 2025-08-13T21:03:43-04:00
Expose Backtraces internals from ghc-experimental
Additionally, expose the same API `base:Control.Exception.Backtrace`
to make it easier to use as a drop-in replacement.
-
a766286f
by Reed Mullanix at 2025-08-13T21:04:36-04:00
ghc-internal: Fix naturalAndNot for NB/NS case
When the first argument to `naturalAndNot` is larger than a `Word` and the second is `Word`-sized, `naturalAndNot` will truncate the
result:
```
>>> naturalAndNot ((2 ^ 65) .|. (2 ^ 3)) (2 ^ 3)
0
```
In contrast, `naturalAndNot` does not truncate when both arguments are larger than a `Word`, so this appears to be a bug.
Luckily, the fix is pretty easy: we just need to call `bigNatAndNotWord#` instead of truncating.
Fixes #26230
-
3506fa7d
by Simon Hengel at 2025-08-13T21:05:18-04:00
Report -pgms as a deprecated flag
(instead of reporting an unspecific warning)
Before:
on the commandline: warning:
Object splitting was removed in GHC 8.8
After:
on the commandline: warning: [GHC-53692] [-Wdeprecated-flags]
-pgms is deprecated: Object splitting was removed in GHC 8.8
-
51c701fe
by Zubin Duggal at 2025-08-13T21:06:00-04:00
testsuite: Be more permissive when filtering out GNU_PROPERTY_TYPE linker warnings
The warning text is slightly different with ld.bfd.
Fixes #26249
-
dfe6f464
by Simon Hengel at 2025-08-13T21:06:43-04:00
Refactoring: Don't misuse `MCDiagnostic` for lint messages
`MCDiagnostic` is meant to be used for compiler diagnostics.
Any code that creates `MCDiagnostic` directly, without going through
`GHC.Driver.Errors.printMessage`, side steps `-fdiagnostics-as-json`
(see e.g. !14475, !14492 !14548).
To avoid this in the future I want to control more narrowly who creates
`MCDiagnostic` (see #24113).
Some parts of the compiler use `MCDiagnostic` purely for formatting
purposes, without creating any real compiler diagnostics. This change
introduces a helper function, `formatDiagnostic`, that can be used in
such cases instead of constructing `MCDiagnostic`.
-
a8b2fbae
by Teo Camarasu at 2025-08-13T21:07:24-04:00
rts: ensure MessageBlackHole.link is always a valid closure
We turn a MessageBlackHole into an StgInd in wakeBlockingQueue().
Therefore it's important that the link field, which becomes the
indirection field, always points to a valid closure.
It's unclear whether it's currently possible for the previous behaviour
to lead to a crash, but it's good to be consistent about this invariant nonetheless.
Co-authored-by: Andreas Klebinger <klebinger.andreas@gmx.at>
-
4021181e
by Teo Camarasu at 2025-08-13T21:07:24-04:00
rts: spin if we see a WHITEHOLE in messageBlackHole
When a BLACKHOLE gets cancelled in raiseAsync, we indirect to a THUNK.
GC can then shortcut this, replacing our BLACKHOLE with a fresh THUNK.
This THUNK is not guaranteed to have a valid indirectee field.
If at the same time, a message intended for the previous BLACKHOLE is
processed and concurrently we BLACKHOLE the THUNK, thus temporarily
turning it into a WHITEHOLE, we can get a segfault, since we look at the
undefined indirectee field of the THUNK
The fix is simple: spin if we see a WHITEHOLE, and it will soon be
replaced with a valid BLACKHOLE.
Resolves #26205
-
1107af89
by Oleg Grenrus at 2025-08-13T21:08:06-04:00
Allow defining HasField instances for naughty fields
Resolves #26295
... as HasField solver doesn't solve for fields with "naughty"
selectors, we could as well allow defining HasField instances for these
fields.
-
020e7587
by Sylvain Henry at 2025-08-13T21:09:00-04:00
Fix Data.List unqualified import warning
-
fd811ded
by Simon Peyton Jones at 2025-08-14T17:56:47-04:00
Make injecting implicit bindings into its own pass
Previously we were injecting "impliicit bindings" (data constructor
worker and wrappers etc)
- both at the end of CoreTidy,
- and at the start of CorePrep
This is unpleasant and confusing. This patch puts it it its own pass,
addImplicitBinds, which runs between the two.
The function `GHC.CoreToStg.AddImplicitBinds.addImplicitBinds` now takes /all/
TyCons, not just the ones for algebraic data types. That change ripples
through to
- corePrepPgm
- doCodeGen
- byteCodeGen
All take [TyCon] which includes all TyCons
-
9bd7fcc5
by Simon Peyton Jones at 2025-08-14T17:56:47-04:00
Implement unary classes
The big change is described exhaustively in
Note [Unary class magic] in GHC.Core.TyCon
Other changes
* We never unbox class dictionaries in worker/wrapper. This has been true for some
time now, but the logic is now centralised in functions in
GHC.Core.Opt.WorkWrap.Utils, namely `canUnboxTyCon`, and `canUnboxArg`
See Note [Do not unbox class dictionaries] in GHC.Core.Opt.WorkWrap.Utils.
* Refactored the `notWorthFloating` logic in GHc.Core.Opt.SetLevels.
I can't remember if I actually changed any behaviour here, but if so it's
only in a corner cases.
* Fixed a bug in `GHC.Core.TyCon.isEnumerationTyCon`, which was wrongly returning
True for (##).
* Remove redundant Role argument to `liftCoSubstWithEx`. It was always
Representational.
* I refactored evidence generation in the constraint solver:
* Made GHC.Tc.Types.Evidence contain better abstactions for evidence
generation.
* I deleted the file `GHC.Tc.Types.EvTerm` and merged its (small) contents
elsewhere. It wasn't paying its way.
* Made evidence for implicit parameters go via a proper abstraction.
* Fix inlineBoringOk; see (IB6) in Note [inlineBoringOk]
This fixes a slowdown in `countdownEffectfulDynLocal`
in the `effectful` library.
Smaller things
* Rename `isDataTyCon` to `isBoxedDataTyCon`.
* GHC.Core.Corecion.liftCoSubstWithEx was only called with Representational role,
so I baked that into the function and removed the argument.
* Get rid of `GHC.Core.TyCon.tyConSingleAlgDataCon_maybe` in favour of calling
`not isNewTyCon` at the call sites; more explicit.
* Refatored `GHC.Core.TyCon.isInjectiveTyCon`; but I don't think I changed its
behaviour
* Moved `decomposeIPPred` to GHC.Core.Predicate
Compile time performance changes:
geo. mean +0.1%
minimum -6.8%
maximum +14.4%
The +14% one is in T21839c, where it seems that a bit more inlining
is taking place. That seems acceptable; and the average change is small
Metric Decrease:
LargeRecord
T12227
T12707
T16577
T21839r
T5642
Metric Increase:
T15164
T21839c
T3294
T5321FD
T5321Fun
WWRec
-
b4075d71
by Simon Peyton Jones at 2025-08-14T17:56:47-04:00
Slight improvement to pre/postInlineUnconditionally
Avoids an extra simplifier iteration
-
9e443596
by Simon Peyton Jones at 2025-08-14T17:56:47-04:00
Fix a long-standing assertion error in normSplitTyConApp_maybe
-
91310ad0
by Simon Peyton Jones at 2025-08-14T17:56:47-04:00
Add comment to coercion optimiser
-
5b841d82
by Teo Camarasu at 2025-08-14T17:57:56-04:00
template-haskell: move some identifiers from ghc-internal to template-haskell
These identifiers are not used internally by the compiler. Therefore we
have no reason for them to be in ghc-internal.
By moving them to template-haskell, we benefit from it being easier to
change them and we avoid having to build them in stage0.
Resolves #26048
-
33e2c7e5
by Teo Camarasu at 2025-08-14T17:57:56-04:00
template-haskell: transfer $infix note to public module
This Haddock note should be in the public facing module
-
2a411fc4
by Sylvain Henry at 2025-08-14T17:59:09-04:00
JS: export HEAP8 symbol (#26290)
Newer Emscripten requires this.
-
248f78ca
by Ben Gamari at 2025-08-14T17:59:51-04:00
users-guide: Drop the THREAD_RUNNABLE event
As of f361281c89fbce42865d8b8b27b0957205366186 it is no longer emitted.
-
706d33e3
by Recursion Ninja at 2025-08-15T04:12:12-04:00
Resolving issues #20645 and #26109
Correctly sign extending and casting smaller bit width types for LLVM operations:
- bitReverse8#
- bitReverse16#
- bitReverse32#
- byteSwap16#
- byteSwap32#
- pdep8#
- pdep16#
- pext8#
- pext16#
-
1cdc6f46
by Cheng Shao at 2025-08-15T04:12:56-04:00
hadrian: enforce have_llvm=False for wasm32/js
This patch fixes hadrian to always pass have_llvm=False to the
testsuite driver for wasm32/js targets. These targets don't really
support the LLVM backend, and the optllvm test way doesn't work. We
used to special-case wasm32/js to avoid auto-adding optllvm way in
testsuite/config/ghc, but this is still problematic if someone writes
a new LLVM-related test and uses something like when(have_llvm(),
extra_ways(["optllvm"])). So better just enforce have_llvm=False for
these targets here.
-
ca03226d
by Ben Gamari at 2025-08-18T13:43:20+00:00
configure: Allow use of LLVM 20
-
783cd7d6
by Cheng Shao at 2025-08-18T20:13:14-04:00
compiler: use `UniqMap` instead of `Map` for `BCEnv` in bytecode compiler
The bytecode compiler maintains a `BCEnv` which was previously `Map Id
StackDepth`. Given `Id` is `Uniquable`, we might as well use `UniqMap`
here as a more efficient data structure, hence this patch.
Co-authored-by: Codex <codex@openai.com>
-
58e46da9
by fendor at 2025-08-18T20:13:56-04:00
rts: Strip lower three bits when hashing Word instead of lower eight bits
-
45dbfa23
by Cheng Shao at 2025-08-18T20:14:37-04:00
libffi: update to 3.5.2
Bumps libffi submodule.
-
54be78ef
by Ben Gamari at 2025-08-19T16:28:05-04:00
testsuite: Fix T20006b
This test is supposed to fail for non-threaded ways yet it
was previously marked as only failing in `normal`.
Fix this.
-
f4bac607
by Simon Peyton Jones at 2025-08-19T16:28:47-04:00
Take yet more care with reporting redundant constraints
This small patch fixes #25992, which relates to reporting redundant
constraints on default-method declarations.
See (TRC5) in Note [Tracking redundant constraints]
-
ab130fec
by fendor at 2025-08-19T16:29:29-04:00
Bump dependencies of hadrian-bootstrap-gen to use GHC 9.6.7
-
6d02ac6f
by fendor at 2025-08-19T16:29:29-04:00
Bump required GHC version for test-bootstrap jobs to 9.10.1
Include test-bootstrap job for GHC 9.12.2.
Update hadrian bootstrap plans use GHC 9.10 and 9.12
Remove older GHC bootstrap configurations.
We require at least GHC 9.10.1 to build GHC.
Adds plans for:
* 9.10.1
* 9.10.2
* 9.12.1
* 9.12.2
-
9e857171
by Brandon Chinn at 2025-08-20T11:47:46-04:00
Don't warn unused-imports with used generated imports
Fixes #21730
* The old notion of "implicit" import has been renamed to "generated". See Note [Generated imports] in GHC.Hs.ImpExp.
* ImportMap now keeps track of generated and user-written imports separately. This avoids the fake SrcSpan we used to give the implicit Prelude import, and the hack that went with it.
* -ddump-minimal-imports now considers generated imports (but still only
warns on + prints user-written imports)
* bestImport considers generated imports to take priority over user-written imports.
-
9fb3bad4
by Ben Gamari at 2025-08-20T11:48:31-04:00
mailmap: Use ben@well-typed.com more liberally
Nearly all of this work was done while working for Well-Typed.
-
774fec37
by Ben Gamari at 2025-08-20T11:49:15-04:00
Add primop to annotate the call stack with arbitrary data
We introduce a new primop `annotateStack#` which allows us to push
arbitrary data onto the call-stack.
This allows us to extract the data later when decoding the stack, for
example when an exception is thrown, showing more information to the
user without having to annotate the full call-stack with `HasCallStack`
constraints.
A new stack frame value is introduced `AnnFrame`, which consists of
nothing but a generic payload.
The primop has a small wrapper API that allows users to annotate their
call-stack in programs.
There is a pure API and an IO-based one. The former is a little bit
dubious, as it affects the evaluation of a program, so use with care.
The latter is "safe", as it doesn't change the evaluation of the
program.
The stack annotation mechanism is similarly implemented to the
`ExceptionAnnotation` and `Exception`, there is a typeclass to indicate
something can be pushed onto the call-stack and all values are wrapped
in the existential `SomeStackAnnotation`, which recover the type of the
annotation payload.
There is currently no builtin way to show the stack annotations when
`Backtraces` are displayed (i.e., when showing stack traces to the user),
which we will address in a follow-up MR.
-------------------------
Metric Increase:
ghc_experimental_so
-------------------------
We increase the size of the package, so this is not unreasonable.
Co-Authored-By: fendor <fendor@posteo.de>
Co-Authored-By: Ben Gamari <bgamari.foss@gmail.com>
-
fdfa3892
by Ben Gamari at 2025-08-20T11:49:57-04:00
testsuite: Add regression test for #24606
-
39b2e382
by Cheng Shao at 2025-08-20T11:50:40-04:00
compiler: only use `Name` instead of `Id` in `SptEntry`
As a part of #26298, this patch refactors `SptEntry` to only carry a
`Name` instead of `Id`: we do not care about extra information like
caffyness or type at all in any static pointer related codegen logic.
This is necessary to make `SptEntry` serializable, as a part of the
grand plan of serializable bytecode.
Co-authored-by: Codex <codex@openai.com>
-
276f8ea8
by Vekhir -- at 2025-08-20T11:51:35-04:00
Bump Cabal dependency
-
0b9c7437
by Zubin Duggal at 2025-08-20T11:52:18-04:00
ci: Teach ci.sh to fetch FreeBSD artifacts from ghcup unofficial bindists and bootstrap compiler on FreeBSD to 9.10.1
Also refactor fetch_ghc logic in ci.sh, renaming the GHC_VERSION enviorment configuration variable to FETCH_GHC_VERSION,
making it clear that it is intended for use on platforms like Windows and FreeBSD where we don't want to use the GHC
excecutable from the platform environment and instead need to download and install GHC-$FETCH_GHC_VERSION from a release
bindist.
Fixes #26296
-
b2914797
by Cheng Shao at 2025-08-20T11:53:00-04:00
driver: use UniqSet for hiddenModules in DynFlags/FinderOpts
This patch replaces Set ModuleName with UniqSet ModuleName in
DynFlags.hiddenModules and FinderOpts.finder_hiddenModules for
improved efficiency.
Co-authored-by: Codex <codex@openai.com>
-
0335d899
by Cheng Shao at 2025-08-20T11:53:00-04:00
driver: use UniqMap ModuleName in the finder
This patch replaces Map ModuleName with UniqMap ModuleName in the
finder for improved efficiency.
Co-authored-by: Codex <codex@openai.com>
-
91f4faaa
by Cheng Shao at 2025-08-20T11:53:43-04:00
configure: check python3 version and require minimal 3.7
Since !9515, the testsuite driver requires python3 version to be at
least 3.7, though this has never been checked by configure logic. This
patch implements the version check. Fixes #23234.
Co-authored-by: Codex <codex@openai.com>
-
df4ee9b4
by Cheng Shao at 2025-08-20T11:54:25-04:00
compiler: use zero cost coerce in GHC.CmmToAsm.CFG.loopInfo
This patch refactors GHC.CmmToAsm.CFG.loopInfo to use zero cost coerce
and thus addresses the TODO. For coerce to work, constructors of
Label/LabelMap/LabelSet from GHC.Cmm.Dataflow.Label are exposed,
though I believe it's a worthy tradeoff to avoid unnecessary runtime
cost without using unsafeCoerce, since the latter could be a landmine
for future refactoring.
Co-authored-by: Codex <codex@openai.com>
-
ccda188d
by Simon Peyton Jones at 2025-08-20T11:55:07-04:00
Start with empty inerts in shortcut solving
When short-cut solving we were starting with an inert set that had
unsolved Wanteds. This caused an infinite loop (#26314), because a
typechecker plugin kept being given that unsolved Wanted.
It's better just to start with an empty inert set
-
c8882ed7
by Ben Gamari at 2025-08-20T11:55:49-04:00
configure: Bump minimal bootstrap GHC version to 9.8
-
f0a19d74
by fendor at 2025-08-20T19:55:00-04:00
Remove deprecated functions from the ghci package
-
ebeb991b
by fendor at 2025-08-20T19:55:00-04:00
base: Remove unstable heap representation details from GHC.Exts
-
e368e247
by Rodrigo Mesquita at 2025-08-20T19:55:42-04:00
bytecode: Use 32bits for breakpoint index
Fixes #26325
-
42724462
by Simon Hengel at 2025-08-21T17:52:11-04:00
Serialize wired-in names as external names when creating HIE files
Note that the domain of de-serialized names stays the same.
Specifically, for known-key names, before `lookupKnownKeyName` was used,
while now this is handled by `lookupOrigNameCache` which captures the
same range provided that the OrigNameCache has been initialized with
`knownKeyNames` (which is the case by default).
(fixes #26238)
-
6a43f8ec
by Cheng Shao at 2025-08-21T17:52:52-04:00
compiler: fix closure C type in SPT init code
This patch fixes the closure C type in SPT init code to StgClosure,
instead of the previously incorrect StgPtr. Having an incorrect C type
makes SPT init code not compatible with other foreign stub generation
logic, which may also emit their own extern declarations for the same
closure symbols and thus will clash with the incorrect prototypes in
SPT init code.
-
5b5d9d47
by Ben Gamari at 2025-08-25T14:29:35-04:00
Revert "STM: don't create a transaction in the rhs of catchRetry# (#26028)"
This reverts commit 0a5836891ca29836a24c306d2a364c2e4b5377fd
-
10f06163
by Cheng Shao at 2025-08-25T14:30:16-04:00
wasm: ensure setKeepCAFs() is called in ghci
This patch is a critical bugfix for #26106, see comment and linked
issue for details.
-
bedc1004
by Cheng Shao at 2025-08-26T09:31:18-04:00
compiler: use zero cost coerce in hoopl setElems/mapToList
This patch is a follow-up of !14680 and changes setElems/mapToList in
GHC/Cmm/Dataflow/Label to use coerce instead of mapping mkHooplLabel
over the keys.
-
13250d97
by Ryan Scott at 2025-08-26T09:31:59-04:00
Reject infix promoted data constructors without DataKinds
In the rename, make sure to apply the same `DataKinds` checks for both
`HsTyVar` (for prefix promoted data constructors) and `HsOpTy` (for infix
promoted data constructors) alike.
Fixes #26318.
-
37655c46
by Teo Camarasu at 2025-08-26T15:24:51-04:00
tests: disable T22859 under LLVM
This test was failing under the LLVM backend since the allocations
differ from the NCG.
Resolves #26282
-
2cbba9d6
by Teo Camarasu at 2025-08-26T15:25:33-04:00
base-exports: update version numbers
As the version of the compiler has been bumped, a lot of the embedded
version numbers will need to be updated if we ever run this test with
`--test-accept` so let's just update them now, and keep future diffs
clean.
-
f9f2ffcf
by Alexandre Esteves at 2025-08-27T07:19:14-04:00
Import new name for 'utimbuf' on windows to fix #26337
Fixes an `-Wincompatible-pointer-types` instance that turns into an error on
recent toolchains and surfaced as such on nixpkgs when doing linux->ucrt cross.
This long-standing warning has been present at least since 9.4:
```
C:\GitLabRunner\builds\0\1709189\tmp\ghc16652_0\ghc_4.c:26:115: error:
warning: incompatible pointer types passing 'struct utimbuf *' to parameter of type 'struct _utimbuf *' [-Wincompatible-pointer-types]
|
26 | HsInt32 ghczuwrapperZC9ZCbaseZCSystemziPosixziInternalsZCzuutime(char* a1, struct utimbuf* a2) {return _utime(a1, a2);}
| ^
HsInt32 ghczuwrapperZC9ZCbaseZCSystemziPosixziInternalsZCzuutime(char* a1, struct utimbuf* a2) {return _utime(a1, a2);}
^~
C:\GitLabRunner\builds\0\1709189\_build\stage0\lib\..\..\mingw\x86_64-w64-mingw32\include\sys\utime.h:109:72: error:
note: passing argument to parameter '_Utimbuf' here
|
109 | __CRT_INLINE int __cdecl _utime(const char *_Filename,struct _utimbuf *_Utimbuf) {
| ^
__CRT_INLINE int __cdecl _utime(const char *_Filename,struct _utimbuf *_Utimbuf) {
```
-
ae89f000
by Hassan Al-Awwadi at 2025-08-27T07:19:56-04:00
Adds the fucnction addDependentDirectory to Q, resolving issue #26148.
This function adds a new directory to the list of things a module depends upon. That means that when the contents of the directory change, the recompilation checker will notice this and the module will be recompiled. Documentation has also been added for addDependentFunction and addDependentDirectory in the user guide.
-
00478944
by Simon Peyton Jones at 2025-08-27T16:48:30+01:00
Comments only
-
a7884589
by Simon Peyton Jones at 2025-08-28T11:08:23+01:00
Type-family occurs check in unification
The occurs check in `GHC.Core.Unify.uVarOrFam` was inadequate in dealing
with type families.
Better now. See Note [The occurs check in the Core unifier].
As I did this I realised that the whole apartness thing is trickier than I
thought: see the new Note [Shortcomings of the apartness test]
-
8adfc222
by sheaf at 2025-08-28T19:47:17-04:00
Fix orientation in HsWrapper composition (<.>)
This commit fixes the order in which WpCast HsWrappers are composed,
fixing a bug introduced in commit 56b32c5a2d5d7cad89a12f4d74dc940e086069d1.
Fixes #26350
-
eb2ab1e2
by Oleg Grenrus at 2025-08-29T11:00:53-04:00
Generalise thNameToGhcName by adding HasHscEnv
There were multiple single monad-specific `getHscEnv` across codebase.
HasHscEnv is modelled on HasDynFlags.
My first idea was to simply add thNameToGhcNameHsc and
thNameToGhcNameTc, but those would been exactly the same
as thNameToGhcName already.
Also add an usage example to thNameToGhcName and mention that it's
recommended way of looking up names in GHC plugins
-
2d575a7f
by fendor at 2025-08-29T11:01:36-04:00
configure: Bump minimal bootstrap GHC version to 9.10
-
716274a5
by Simon Peyton Jones at 2025-08-29T17:27:12-04:00
Fix deep subsumption again
This commit fixed #26255:
commit 56b32c5a2d5d7cad89a12f4d74dc940e086069d1
Author: sheaf <sam.derbyshire@gmail.com>
Date: Mon Aug 11 15:50:47 2025 +0200
Improve deep subsumption
This commit improves the DeepSubsumption sub-typing implementation
in GHC.Tc.Utils.Unify.tc_sub_type_deep by being less eager to fall back
to unification.
But alas it still wasn't quite right for view patterns: #26331
This MR does a generalisation to fix it. A bit of a sledgehammer to crack
a nut, but nice.
* Add a field `ir_inst :: InferInstFlag` to `InferResult`, where
```
data InferInstFlag = IIF_Sigma | IIF_ShallowRho | IIF_DeepRho
```
* The flag says exactly how much `fillInferResult` should instantiate
before filling the hole.
* We can also use this to replace the previous very ad-hoc `tcInferSigma`
that was used to implement GHCi's `:type` command.
-
27206c5e
by sheaf at 2025-08-29T17:28:14-04:00
Back-compat for TH SpecialiseP data-con of Pragma
This commit improves the backwards-compatibility story for the
SpecialiseP constructor of the Template Haskell 'Pragma' datatype.
Instead of keeping the constructor but deprecating it, this commit makes
it into a bundled pattern synonym of the Pragma datatype. We no longer
deprecate it; it's useful for handling old-form specialise pragmas.
-
26dbcf61
by fendor at 2025-08-30T05:10:08-04:00
Move stack decoding logic from ghc-heap to ghc-internal
The stack decoding logic in `ghc-heap` is more sophisticated than the one
currently employed in `CloneStack`. We want to use the stack decoding
implementation from `ghc-heap` in `base`.
We cannot simply depend on `ghc-heap` in `base` due do bootstrapping
issues.
Thus, we move the code that is necessary to implement stack decoding to
`ghc-internal`. This is the right location, as we don't want to add a
new API to `base`.
Moving the stack decoding logic and re-exposing it in ghc-heap is
insufficient, though, as we have a dependency cycle between.
* ghc-heap depends on stage1:ghc-internal
* stage0:ghc depends on stage0:ghc-heap
To fix this, we remove ghc-heap from the set of `stage0` dependencies.
This is not entirely straight-forward, as a couple of boot dependencies,
such as `ghci` depend on `ghc-heap`.
Luckily, the boot compiler of GHC is now >=9.10, so we can migrate `ghci`
to use `ghc-internal` instead of `ghc-heap`, which already exports the
relevant modules.
However, we cannot 100% remove ghc's dependency on `ghc-heap`, since
when we compile `stage0:ghc`, `stage1:ghc-internal` is not yet
available.
Thus, when we compile with the boot-compiler, we still depend on an
older version of `ghc-heap`, and only use the modules from `ghc-internal`,
if the `ghc-internal` version is recent enough.
-------------------------
Metric Increase:
T24602_perf_size
T25046_perf_size_gzip
T25046_perf_size_unicode
T25046_perf_size_unicode_gzip
size_hello_artifact
size_hello_artifact_gzip
size_hello_unicode
size_hello_unicode_gzip
-------------------------
These metric increases are unfortunate, they are most likely caused by
the larger (literally in terms of lines of code) stack decoder implementation
that are now linked into hello-word binaries.
On linux, it is almost a 10% increase, which is considerable.
-
bd80bb70
by fendor at 2025-08-30T05:10:08-04:00
Implement `decode` in terms of `decodeStackWithIpe`
Uses the more efficient stack decoder implementation.
-
24441165
by fendor at 2025-08-30T05:10:08-04:00
Remove stg_decodeStackzh
-
fb9cc882
by Simon Peyton Jones at 2025-08-30T05:10:51-04:00
Fix a long standing bug in the coercion optimiser
We were mis-optimising ForAllCo, leading to #26345
Part of the poblem was the tricky tower of abstractions leading to
the dreadful
GHC.Core.TyCo.Subst.substForAllCoTyVarBndrUsing
This function was serving two masters: regular substitution, but also
coercion optimsation. So tricky was it that it did so wrong.
In this MR I locate all the fancy footwork for coercion optimisation
in GHC.Core.Coercion.Opt, where it belongs. That leaves substitution
free to be much simpler.
-
6c78de2d
by Sylvain Henry at 2025-09-01T08:46:19-04:00
Driver: substitute virtual Prim module in --make mode too
When we build ghc-internal with --make (e.g. with cabal-install), we
need to be careful to substitute the virtual interface file for
GHC.Internal.Prim:
- after code generation (we generate code for an empty module, so we get
an empty interface)
- when we try to reload its .hi file
-
26e0db16
by fendor at 2025-09-01T08:47:01-04:00
Expose Stack Annotation frames in IPE backtraces by default
When decoding the Haskell-native call stack and displaying the IPE information
for the stack frames, we print the `StackAnnotation` of the `AnnFrame` by default.
This means, when an exception is thrown, any intermediate stack annotations will
be displayed in the `IPE Backtrace`.
Example backtrace:
```
Exception: ghc-internal:GHC.Internal.Exception.ErrorCall:
Oh no!
IPE backtrace:
annotateCallStackIO, called at app/Main.hs:48:10 in backtrace-0.1.0.0-inplace-server:Main
annotateCallStackIO, called at app/Main.hs:46:13 in backtrace-0.1.0.0-inplace-server:Main
Main.handler (app/Main.hs:(46,1)-(49,30))
Main.liftIO (src/Servant/Server/Internal/Handler.hs:30:36-42)
Servant.Server.Internal.Delayed.runHandler' (src/Servant/Server/Internal/Handler.hs:27:31-41)
Control.Monad.Trans.Resource.runResourceT (./Control/Monad/Trans/Resource.hs:(192,14)-(197,18))
Network.Wai.Handler.Warp.HTTP1.processRequest (./Network/Wai/Handler/Warp/HTTP1.hs:195:20-22)
Network.Wai.Handler.Warp.HTTP1.processRequest (./Network/Wai/Handler/Warp/HTTP1.hs:(195,5)-(203,31))
Network.Wai.Handler.Warp.HTTP1.http1server.loop (./Network/Wai/Handler/Warp/HTTP1.hs:(141,9)-(157,42))
HasCallStack backtrace:
error, called at app/Main.hs:48:32 in backtrace-0.1.0.0-inplace-server:Main
```
The first two entries have been added by `annotateCallStackIO`, defined in `annotateCallStackIO`.
-
a1567efd
by Sylvain Henry at 2025-09-01T23:01:35-04:00
RTS: rely less on Hadrian for flag setting (#25843)
Hadrian used to pass -Dfoo command-line flags directly to build the rts.
We can replace most of these flags with CPP based on cabal flags.
It makes building boot libraries with cabal-install simpler (cf #25843).
-
ca5b0283
by Sergey Vinokurov at 2025-09-01T23:02:23-04:00
Remove unnecessary irrefutable patterns from Bifunctor instances for tuples
Implementation of https://github.com/haskell/core-libraries-committee/issues/339
Metric Decrease:
mhu-perf
-
2da84b7a
by sheaf at 2025-09-01T23:03:23-04:00
Only use active rules when simplifying rule RHSs
When we are simplifying the RHS of a rule, we make sure to only apply
rewrites from rules that are active throughout the original rule's
range of active phases.
For example, if a rule is always active, we only fire rules that are
themselves always active when simplifying the RHS. Ditto for inline
activations.
This is achieved by setting the simplifier phase to a range of phases,
using the new SimplPhaseRange constructor. Then:
1. When simplifying the RHS of a rule, or of a stable unfolding,
we set the simplifier phase to a range of phases, computed from
the activation of the RULE/unfolding activation, using the
function 'phaseFromActivation'.
The details are explained in Note [What is active in the RHS of a RULE?]
in GHC.Core.Opt.Simplify.Utils.
2. The activation check for other rules and inlinings is then:
does the activation of the other rule/inlining cover the whole
phase range set in sm_phase? This continues to use the 'isActive'
function, which now accounts for phase ranges.
On the way, this commit also moves the exact-print SourceText annotation
from the Activation datatype to the ActivationAnn type. This keeps the
main Activation datatype free of any extra cruft.
Fixes #26323
-
79816cc4
by Rodrigo Mesquita at 2025-09-02T12:19:59-04:00
cleanup: Move dehydrateCgBreakInfo to Stg2Bc
This no longer has anything to do with Core.
-
53da94ff
by Rodrigo Mesquita at 2025-09-02T12:19:59-04:00
rts/Disassembler: Fix spacing of BRK_FUN
-
08c0cf85
by Rodrigo Mesquita at 2025-09-02T12:19:59-04:00
debugger: Fix bciPtr in Step-out
We need to use `BCO_NEXT` to move bciPtr to ix=1, because ix=0 points to
the instruction itself!
I do not understand how this didn't crash before.
-
e7e021fa
by Rodrigo Mesquita at 2025-09-02T12:19:59-04:00
debugger: Allow BRK_FUNs to head case continuation BCOs
When we start executing a BCO, we may want to yield to the scheduler:
this may be triggered by a heap/stack check, context switch, or a
breakpoint. To yield, we need to put the stack in a state such that
when execution is resumed we are back to where we yielded from.
Previously, a BKR_FUN could only head a function BCO because we only
knew how to construct a valid stack for yielding from one -- simply add
`apply_interp_info` + the BCO to resume executing. This is valid because
the stack at the start of run_BCO is headed by that BCO's arguments.
However, in case continuation BCOs (as per Note [Case continuation BCOs]),
we couldn't easily reconstruct a valid stack that could be resumed
because we dropped too soon the stack frames regarding the value
returned (stg_ret) and received (stg_ctoi) by that continuation.
This is especially tricky because of the variable type and size return
frames (e.g. pointer ret_p/ctoi_R1p vs a tuple ret_t/ctoi_t2).
The trick to being able to yield from a BRK_FUN at the start of a case
cont BCO is to stop removing the ret frame headers eagerly and instead
keep them until the BCO starts executing. The new layout at the start of
a case cont. BCO is described by the new Note [Stack layout when entering run_BCO].
Now, we keep the ret_* and ctoi_* frames when entering run_BCO.
A BRK_FUN is then executed if found, and the stack is yielded as-is with
the preserved ret and ctoi frames.
Then, a case cont BCO's instructions always SLIDE off the headers of the
ret and ctoi frames, in StgToByteCode.doCase, turning a stack like
| .... |
+---------------+
| fv2 |
+---------------+
| fv1 |
+---------------+
| BCO |
+---------------+
| stg_ctoi_ret_ |
+---------------+
| retval |
+---------------+
| stg_ret_..... |
+---------------+
into
| .... |
+---------------+
| fv2 |
+---------------+
| fv1 |
+---------------+
| retval |
+---------------+
for the remainder of the BCO.
Moreover, this more uniform approach of keeping the ret and ctoi frames
means we need less ad-hoc logic concerning the variable size of
ret_tuple vs ret_p/np frames in the code generator and interpreter:
Always keep the return to cont. stack intact at the start of run_BCO,
and the statically generated instructions will take care of adjusting
it.
Unlocks BRK_FUNs at the start of case cont. BCOs which will enable a
better user-facing step-out (#26042) which is free of the bugs the
current BRK_ALTS implementation suffers from (namely, using BRK_FUN
rather than BRK_ALTS in a case cont. means we'll never accidentally end
up in a breakpoint "deeper" than the continuation, because we stop at
the case cont itself rather than on the first breakpoint we evaluate
after it).
-
ade3c1e6
by Rodrigo Mesquita at 2025-09-02T12:19:59-04:00
BRK_FUN with InternalBreakLocs for code-generation time breakpoints
At the start of a case continuation BCO, place a BRK_FUN.
This BRK_FUN uses the new "internal breakpoint location" -- allowing us
to come up with a valid source location for this breakpoint that is not associated with a source-level tick.
For case continuation BCOs, we use the last tick seen before it as the
source location. The reasoning is described in Note [Debugger: Stepout internal break locs].
Note how T26042c, which was broken because it displayed the incorrect
behavior of the previous step out when we'd end up at a deeper level
than the one from which we initiated step-out, is now fixed.
As of this commit, BRK_ALTS is now dead code and is thus dropped.
Note [Debugger: Stepout internal break locs]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Step-out tells the interpreter to run until the current function
returns to where it was called from, and stop there.
This is achieved by enabling the BRK_FUN found on the first RET_BCO
frame on the stack (See [Note Debugger: Step-out]).
Case continuation BCOs (which select an alternative branch) must
therefore be headed by a BRK_FUN. An example:
f x = case g x of <--- end up here
1 -> ...
2 -> ...
g y = ... <--- step out from here
- `g` will return a value to the case continuation BCO in `f`
- The case continuation BCO will receive the value returned from g
- Match on it and push the alternative continuation for that branch
- And then enter that alternative.
If we step-out of `g`, the first RET_BCO on the stack is the case
continuation of `f` -- execution should stop at its start, before
selecting an alternative. (One might ask, "why not enable the breakpoint
in the alternative instead?", because the alternative continuation is
only pushed to the stack *after* it is selected by the case cont. BCO)
However, the case cont. BCO is not associated with any source-level
tick, it is merely the glue code which selects alternatives which do
have source level ticks. Therefore, we have to come up at code
generation time with a breakpoint location ('InternalBreakLoc') to
display to the user when it is stopped there.
Our solution is to use the last tick seen just before reaching the case
continuation. This is robust because a case continuation will thus
always have a relevant breakpoint location:
- The source location will be the last source-relevant expression
executed before the continuation is pushed
- So the source location will point to the thing you've just stepped
out of
- Doing :step-local from there will put you on the selected
alternative (which at the source level may also be the e.g. next
line in a do-block)
Examples, using angle brackets (<<...>>) to denote the breakpoint span:
f x = case <<g x>> {- step in here -} of
1 -> ...
2 -> ...>
g y = <<...>> <--- step out from here
...
f x = <<case g x of <--- end up here, whole case highlighted
1 -> ...
2 -> ...>>
doing :step-local ...
f x = case g x of
1 -> <<...>> <--- stop in the alternative
2 -> ...
A second example based on T26042d2, where the source is a do-block IO
action, optimised to a chain of `case expressions`.
main = do
putStrLn "hello1"
<<f>> <--- step-in here
putStrLn "hello3"
putStrLn "hello4"
f = do
<<putStrLn "hello2.1">> <--- step-out from here
putStrLn "hello2.2"
...
main = do
putStrLn "hello1"
<<f>> <--- end up here again, the previously executed expression
putStrLn "hello3"
putStrLn "hello4"
doing step/step-local ...
main = do
putStrLn "hello1"
f
<<putStrLn "hello3">> <--- straight to the next line
putStrLn "hello4"
Finishes #26042
-
c66910c0
by Rodrigo Mesquita at 2025-09-02T12:19:59-04:00
debugger: Re-use the last BreakpointId whole in step-out
Previously, to come up with a location to stop at for `:stepout`, we
would store the location of the last BreakpointId surrounding the
continuation, as described by Note [Debugger: Stepout internal break locs].
However, re-using just the location from the last source breakpoint
isn't sufficient to provide the necessary information in the break
location. Specifically, it wouldn't bind any variables at that location.
Really, there is no reason not to re-use the last breakpoint wholesale,
and re-use all the information we had there. Step-out should behave just
as if we had stopped at the call, but s.t. continuing will not
re-execute the call.
This commit updates the CgBreakInfo to always store a BreakpointId, be
it the original one or the one we're emulating (for step-out).
It makes variable bindings on :stepout work
-
e4abed7b
by sheaf at 2025-09-02T12:20:40-04:00
Revert accidental changes to hie.yaml
-
003b715b
by meooow25 at 2025-09-02T23:48:51+02:00
Adjust the strictness of Data.List.iterate'
* Don't force the next element in advance when generating a (:).
* Force the first element to WHNF like every other element.
Now every element in the output list is forced to WHNF when the (:)
containing it is forced.
CLC proposal:
https://github.com/haskell/core-libraries-committee/issues/335
-
b2f6aad0
by Simon Hengel at 2025-09-03T04:36:10-04:00
Refactoring: More consistently use logOutput, logInfo, fatalErrorMsg
-
60a16db7
by Rodrigo Mesquita at 2025-09-03T10:55:50+01:00
bytecode: Don't PUSH_L 0; SLIDE 1 1
While looking through bytecode I noticed a quite common unfortunate
pattern:
...
PUSH_L 0
SLIDE 1 1
We do this often by generically constructing a tail call from a function
atom that may be somewhere arbitrary on the stack.
However, for the special case that the function can be found directly on
top of the stack, as part of the arguments, it's plain redundant to push
then slide it.
In this commit we add a small optimisation to the generation of
tailcalls in bytecode. Simply: lookahead for the function in the stack.
If it is the first thing on the stack and it is part of the arguments
which would be dropped as we entered the tail call, then don't push then
slide it.
In a simple example (T26042b), this already produced a drastic
improvement in generated code (left is old, right is with this patch):
```diff
3c3
< 2025-07-29 10:14:02.081277 UTC
---
> 2025-07-29 10:50:36.560949 UTC
160,161c160
< PUSH_L 0
< SLIDE 1 2
---
> SLIDE 1 1
164,165d162
< PUSH_L 0
< SLIDE 1 1
175,176c172
< PUSH_L 0
< SLIDE 1 2
---
> SLIDE 1 1
179,180d174
< PUSH_L 0
< SLIDE 1 1
206,207d199
< PUSH_L 0
< SLIDE 1 1
210,211d201
< PUSH_L 0
< SLIDE 1 1
214,215d203
< PUSH_L 0
< SLIDE 1 1
218,219d205
< PUSH_L 0
< SLIDE 1 1
222,223d207
< PUSH_L 0
< SLIDE 1 1
...
600,601c566
< PUSH_L 0
< SLIDE 1 2
---
> SLIDE 1 1
604,605d568
< PUSH_L 0
< SLIDE 1 1
632,633d594
< PUSH_L 0
< SLIDE 1 1
636,637d596
< PUSH_L 0
< SLIDE 1 1
640,641d598
< PUSH_L 0
< SLIDE 1 1
644,645d600
< PUSH_L 0
< SLIDE 1 1
648,649d602
< PUSH_L 0
< SLIDE 1 1
652,653d604
< PUSH_L 0
< SLIDE 1 1
656,657d606
< PUSH_L 0
< SLIDE 1 1
660,661d608
< PUSH_L 0
< SLIDE 1 1
664,665d610
< PUSH_L 0
< SLIDE 1 1
```
I also compiled lib:Cabal to bytecode and counted the number of bytecode
lines with `find dist-newstyle -name "*.dump-BCOs" -exec wc {} +`:
with unoptimized core:
1190689 lines (before) - 1172891 lines (now)
= 17798 less redundant instructions (-1.5% lines)
with optimized core:
1924818 lines (before) - 1864836 lines (now)
= 59982 less redundant instructions (-3.1% lines)
-
8b2c72c0
by L0neGamer at 2025-09-04T06:32:03-04:00
Add Control.Monad.thenM and Control.Applicative.thenA
-
39e1b7cb
by Teo Camarasu at 2025-09-04T06:32:46-04:00
ghc-internal: invert dependency of GHC.Internal.TH.Syntax on Data.Data
This means that Data.Data no longer blocks building TH.Syntax, which
allows greater parallelism in our builds.
We move the Data.Data.Data instances to Data.Data. Quasi depends on
Data.Data for one of its methods, so,
we split the Quasi/Q, etc definition out of GHC.Internal.TH.Syntax
into its own module. This has the added benefit of splitting up this
quite large module.
Previously TH.Syntax was a bottleneck when compiling ghc-internal. Now
it is less of a bottle-neck and is also slightly quicker to
compile (since it no longer contains these instances) at the cost of
making Data.Data slightly more expensive to compile.
TH.Lift which depends on TH.Syntax can also compile quicker and no
longer blocks ghc-internal finishing to compile.
Resolves #26217
-------------------------
Metric Decrease:
MultiLayerModulesTH_OneShot
T13253
T21839c
T24471
Metric Increase:
T12227
-------------------------
-
bdf82fd2
by Teo Camarasu at 2025-09-04T06:32:46-04:00
compiler: delete unused names in Builtins.Names.TH
returnQ and bindQ are no longer used in the compiler.
There was also a very old comment that referred to them that I have modernized
-
41a448e5
by Ben Gamari at 2025-09-04T19:21:43-04:00
hadrian: Pass lib & include directories to ghc `Setup configure`
-
46bb9a79
by Ben Gamari at 2025-09-04T19:21:44-04:00
rts/IPE: Fix compilation when zstd is enabled
This was broken by the refactoring undertaken in
c80dd91c0bf6ac034f0c592f16c548b9408a8481.
Closes #26312.
-
138a6e34
by sheaf at 2025-09-04T19:22:46-04:00
Make mkCast assertion a bit clearer
This commit changes the assertion message that gets printed when one
calls mkCast with a coercion whose kind does not match the type of the
inner expression. I always found the assertion message a bit confusing,
as it didn't clearly state what exactly was the error.
-
9d626be1
by sheaf at 2025-09-04T19:22:46-04:00
Simplifier/rules: fix mistakes in Notes & comments
-
94b62aa7
by Simon Peyton Jones at 2025-09-08T03:37:14-04:00
Refactor ForAllCo
This is a pure refactor, addressing #26389.
It arranges that the kind coercion in a ForAllCo is a MCoercion, rather
than a plain Coercion, thus removing redundancy in the common case.
See (FC8) in Note [ForAllCo]
It's a nice cleanup.
-
624afa4a
by sheaf at 2025-09-08T03:38:05-04:00
Use tcMkScaledFunTys in matchExpectedFunTys
We should use tcMkScaledFunTys rather than mkScaledFunTys in
GHC.Tc.Utils.Unify.matchExpectedFunTys, as the latter crashes
when the kind of the result type is a bare metavariable.
We know the result is always Type-like, so we don't need scaledFunTys
to try to rediscover that from the kind.
Fixes #26277
-
0975d2b6
by sheaf at 2025-09-08T03:38:54-04:00
Revert "Remove hptAllFamInstances usage during upsweep"
This reverts commit 3bf6720eff5e86e673568e756161e6d6150eb440.
-
0cf34176
by soulomoon at 2025-09-08T03:38:54-04:00
Family consistency checks: add test for #26154
This commit adds the test T26154, to make sure that GHC doesn't crash
when performing type family consistency checks. This test case
was extracted from Agda.
Fixes #26154
-
ba210d98
by Simon Peyton Jones at 2025-09-08T16:26:36+01:00
Report solid equality errors before custom errors
This MR fixes #26255 by
* Reporting solid equality errors like
Int ~ Bool
before "custom type errors". See comments in `report1` in
`reportWanteds`
* Suppressing errors that arise from superclasses of
Wanteds. See (SCE1) in Note [Suppressing confusing errors]
More details in #26255.
-
b6249140
by Simon Peyton Jones at 2025-09-10T10:42:38-04:00
Fix a scoping error in Specialise
This small patch fixes #26329, which triggered a scoping error.
Test is in T21391, with -fpolymorphic-specialisation enabled
-
45305ab8
by sheaf at 2025-09-10T10:43:29-04:00
Make rationalTo{Float,Double} inline in phase 0
We hold off on inlining these until phase 0 to allow constant-folding
rules to fire. However, once we get to phase 0, we should inline them,
e.g. to expose unboxing opportunities.
See CLC proposal #356.
-
0959d4bc
by Andreas Klebinger at 2025-09-10T10:44:12-04:00
Add regression test for #26056
-
dc79593d
by sheaf at 2025-09-10T10:45:01-04:00
Deep subsumption: unify mults without tcEqMult
As seen in #26332, we may well end up with a non-reflexive multiplicity
coercion when doing deep subsumption. We should do the same thing that
we do without deep subsumption: unify the multiplicities normally,
without requiring that the coercion is reflexive (which is what
'tcEqMult' was doing).
Fixes #26332
-
4bfe2269
by sheaf at 2025-09-10T10:45:50-04:00
lint-codes: fixup MSYS drive letter on Windows
This change ensures that System.Directory.listDirectory doesn't trip up
on an MSYS-style path like '/c/Foo' when trying to list all testsuite
stdout/stderr files as required for testing coverage of GHC diagnostic
codes in the testsuite.
Fixes #25178
-
56540775
by Ben Gamari at 2025-09-10T10:46:32-04:00
gitlab-ci: Disable split sections on FreeBSD
Due to #26303.
-
1537784b
by Moritz Angermann at 2025-09-10T10:47:13-04:00
Improve mach-o relocation information
This change adds more information about the symbol and addresses
we try to relocate in the linker. This significantly helps when
deubbging relocation issues reported by users.
-
4e67855b
by Moritz Angermann at 2025-09-10T10:47:54-04:00
test.mk expect GhcLeadingUnderscore, not LeadingUnderscore (in line with the other Ghc prefixed variables.
-
c1cdd265
by Moritz Angermann at 2025-09-10T10:48:35-04:00
testsuite: Fix broken exec_signals_child.c
There is no signal 0. The signal mask is 1-32.
-
99ac335c
by Moritz Angermann at 2025-09-10T10:49:15-04:00
testsuite: clarify Windows/Darwin locale rationale for skipping T6037 T2507 T8959a
-
0e8fa77a
by Moritz Angermann at 2025-09-10T10:49:56-04:00
Skip broken tests on macOS (due to leading underscore not handled properly in the expected output.)
-
28570c59
by Zubin Duggal at 2025-09-10T10:50:37-04:00
docs(sphinx): fix links to reverse flags when using the :ghc-flag:`-fno-<flag>` syntax
This solution is rather hacky and I suspect there is a better way to do this but I don't know
enough about Sphinx to do better.
Fixes #26352
-
d17257ed
by Cheng Shao at 2025-09-10T17:01:27+02:00
rel-eng: update alpine images to 3.22
This patch is a part of #25876 and updates alpine images to 3.22,
while still retaining 3.12 for x86_64 fully_static bindists.
-------------------------
Metric Decrease:
MultiComponentModulesRecomp
-------------------------
-
db3276bb
by Sylvain Henry at 2025-09-11T11:27:28-04:00
T16180: indicate that the stack isn't executable
-
11eeeba7
by Sylvain Henry at 2025-09-11T11:27:28-04:00
Fix some tests (statically linked GHC vs libc)
When GHC is linked statically, the stdout C global variable that GHC uses
isn't shared with the stdout C global variable used by loaded code.
As a consequence, the latter must be explicitly flushed because GHC
won't flush it before exiting.
-
80a07571
by Sylvain Henry at 2025-09-11T11:28:18-04:00
Testsuite: fix debug_rts detection
Running the testsuite without Hadrian should set config.debug_rts
correctly too.
-
62ae97de
by Duncan Coutts at 2025-09-12T13:23:33-04:00
Handle heap allocation failure in I/O primops
The current I/O managers do not use allocateMightFail, but future ones
will. To support this properly we need to be able to return to the
primop with a failure. We simply use a bool return value.
Currently however, we will just throw an exception rather than calling
the GC because that's what all the other primops do too.
For the general issue of primops invoking GC and retrying, see
https://gitlab.haskell.org/ghc/ghc/-/issues/24105
-
cb9093f5
by Duncan Coutts at 2025-09-12T13:23:33-04:00
Move (and rename) scheduleStartSignalHandlers into RtsSignals.h
Previously it was a local helper (static) function in Schedule.c.
Rename it to startPendingSignalHandlers and deifine it as an inline
header function in RtsSignals.h. So it should still be fast.
Each (new style) I/O manager is going to need to do the same, so eliminating
the duplication now makes sense.
-
9736d44a
by Duncan Coutts at 2025-09-12T13:23:33-04:00
Reduce detail in printThreadBlockage I/O blocking cases
The printThreadBlockage is used in debug tracing output.
For the cases BlockedOn{Read,Write,Delay} the output previously included
the fd that was being waited on, and the delay target wake time.
Superficially this sounds useful, but it's clearly not that useful
because it was already wrong for the Win32 non-threaded I/O manager. In
that situation it will print garbage (the async_result pointer, cast to
a fd or a time).
So given that it apparently never mattered that the information was
accurate, then it's hardly a big jump to say it doesn't matter if it is
present at all.
A good reason to remove it is that otherwise we have to make a new
API and a per-I/O manager implementation to fetch the information. And
for some I/O manager implementations, this information is not available.
It is not available in the win32 non-threaded I/O manager. And for some
future Linux ones, there is no need for the fd to be stored, so storing
it would be just extra space used for very little gain.
So the simplest thing is to just remove the detail.
-
bc0f2d5d
by Duncan Coutts at 2025-09-12T13:23:33-04:00
Add TimeoutQueue.{c,h} and corresponding tests
A data structure used to efficiently manage a collection of timeouts.
It is a priority queue based on absolute expiry time. It uses 64bit
high-precision Time for the keys. The values are normal closures which
allows for example using MVars for unblocking.
It is common in many applications for timeouts to be created and then
deleted or altered before they expire. Thus the choice of data structure
for timeouts should support this efficiently. The implementation choice
here is a leftist heap with the extra feature that it supports deleting
arbitrary elements, provided the caller retain a pointer to the element.
While the deleteMin operation takes O(log n) time, as in all heap
structures, the delete operation for arbitrary elements /typically/
takes O(1), and only O(log n) in the worst case. In practice, when
managing thousands of timeouts it can be a factor of 10 faster to delete
a random timeout queue element than to remove the minimum element. This
supports the common use case.
The plan is to use it in some of the RTS-side I/O managers to support
their timer functionality. In this use case the heap value will be an
MVar used for each timeout to unblock waiting threads.
-
d1679c9d
by Duncan Coutts at 2025-09-12T13:23:33-04:00
Add ClosureTable.{c,h} and corresponding tests
A table of pointers to closures on the GC heap with stable indexes.
It provides O(1) alloc, free and lookup. The table can be expanded
using a simple doubling strategy: in which case allocation is typically
O(1) and occasionally O(n) for overall amortised O(1). No shrinking is
used.
The table itself is heap allocated, and points to other heap objects.
As such it's necessary to use markClosureTable to ensure the table is
used as a GC root to keep the table entries alive, and maintain proper
pointers to them as the GC moves heap objects about.
It is designed to be allocated and accesses exclusively from a single
capability, enabling it to work without any locking. It is thus similar
to the StablePtr table, but per-capability which removes the need for
locking. It _should_ also provide lower GC pause times with the
non-moving GC by spending only O(1) time in markClosureTable, vs O(n)
for markStablePtrTable.
The plan is to use it in some of the I/O managers to keep track of
in-flight I/O operations (but not timers). This allows the tracking
info to be kept on the (unpinned) GC heap, and shared with Haskell
code, and by putting a pointer to the tracking information in a table,
the index remains stable and can be passed via foreign code (like the
kernel).
-
78cb8dd5
by Duncan Coutts at 2025-09-12T13:23:33-04:00
Add the StgAsyncIOOp closure type
This is intended to be used by multiple I/O managers to help with
tracking in-flight I/O operations.
It is called asynchronous because from the point of view of the RTS we
have many such operations in progress at once. From the point of view of
a Haskell thread of course it can look synchronous.
-
a2839896
by Duncan Coutts at 2025-09-12T13:23:33-04:00
Add StgAsyncIOOp and StgTimeoutQueue to tso->block_info
These will be used by new I/O managers, for threads blocked on I/O or
timeouts.
-
fdc2451c
by Duncan Coutts at 2025-09-12T13:23:33-04:00
Add a new I/O manager based on poll()
This is a proof of concept I/O manager, to show how to add new ones
neatly, using the ClosureTable and TimeoutQueue infrastructure.
It uses the old unix poll() API, so it is of course limited in
performance by that, but it should have the benefit of wide
compatibility. Also we neatly avoid a name clash with the existing
select() I/O manager.
Compared to the select() I/O manager:
1. beause it uses poll() it is not limited to 1024 file descriptors
(but it's still O(n) so don't expect great performance);
2. it should have much faster threadDelay (when using it in lots of
threads at once) because it's based on the new TimeoutQueue which is
O(log n) rather than O(n).
Some of the code related to timers/timouts is put into a shared module
rts/posix/Timeout.{h,c} since it is intended to be shared with other
similar I/O managers.
-
6c273b76
by Duncan Coutts at 2025-09-12T13:23:34-04:00
Document the I/O managers in the user guide
and note the new poll I/O manager in the release notes.
-
824fab74
by Duncan Coutts at 2025-09-12T13:23:34-04:00
Use the poll() I/O manager by default
That is, for the non-threaded RTS, prefer the poll I/O manager over the
legacy select() one, if both can be enabled.
This patch is primarily for CI testing, so we should probably remove
this patch before merging. We can change defaults later after wider
testing and feedback.
-
39392532
by Luite Stegeman at 2025-09-12T13:24:16-04:00
Support larger unboxed sums
Change known constructor encoding for sums in interfaces to use
11 bits for both the arity and the alternative (up from 8 and 6,
respectively)
-
2af12e21
by Luite Stegeman at 2025-09-12T13:24:16-04:00
Decompose padding smallest-first in Cmm toplevel data constructors
This makes each individual padding value aligned
-
418fa78f
by Luite Stegeman at 2025-09-12T13:24:16-04:00
Use slots smaller than word as tag for smaller unboxed sums
This packs unboxed sums more efficiently by allowing
Word8, Word16 and Word32 for the tag field if the number of
constructors is small enough
-
8d7e912f
by Rodrigo Mesquita at 2025-09-12T17:57:24-04:00
ghc-toolchain: Use ByteOrder rather than new Endianness
Don't introduce a duplicate datatype when the previous one is equivalent
and already used elsewhere. This avoids unnecessary translation between
the two.
-
7d378476
by Rodrigo Mesquita at 2025-09-12T17:57:24-04:00
Read Toolchain.Target files rather than 'settings'
This commit makes GHC read `lib/targets/default.target`, a file with a
serialized value of `ghc-toolchain`'s `GHC.Toolchain.Target`.
Moreover, it removes all the now-redundant entries from `lib/settings`
that are configured as part of a `Target` but were being written into
`settings`.
This makes it easier to support multiple targets from the same compiler
(aka runtime retargetability). `ghc-toolchain` can be re-run many times
standalone to produce a `Target` description for different targets, and,
in the future, GHC will be able to pick at runtime amongst different
`Target` files.
This commit only makes it read the default `Target` configured in-tree
or configured when installing the bindist.
The remaining bits of `settings` need to be moved to `Target` in follow
up commits, but ultimately they all should be moved since they are
per-target relevant.
Fixes #24212
On Windows, the constant overhead of parsing a slightly more complex
data structure causes some small-allocation tests to wiggle around 1 to
2 extra MB (1-2% in these cases).
-------------------------
Metric Increase:
MultiLayerModulesTH_OneShot
T10421
T10547
T12234
T12425
T13035
T18140
T18923
T9198
TcPlugin_RewritePerf
-------------------------
-
e0780a16
by Rodrigo Mesquita at 2025-09-12T17:57:24-04:00
ghc-toolchain: Move TgtHasLibm to per-Target file
TargetHasLibm is now part of the per-target configuration
Towards #26227
-
8235dd8c
by Rodrigo Mesquita at 2025-09-12T17:57:24-04:00
ghc-toolchain: Move UseLibdw to per-Target file
To support DWARF unwinding, the RTS must be built with the -f+libdw flag
and with the -DUSE_LIBDW macro definition. These flags are passed on
build by Hadrian when --enable-dwarf-unwinding is specified at configure
time.
Whether the RTS was built with support for DWARF is a per-target
property, and as such, it was moved to the per-target
GHC.Toolchain.Target.Target file.
Additionally, we keep in the target file the include and library paths
for finding libdw, since libdw should be checked at configure time (be
it by configure, or ghc-toolchain, that libdw is properly available).
Preserving the user-given include paths for libdw facilitates in the
future building the RTS on demand for a given target (if we didn't keep
that user input, we couldn't)
Towards #26227
-
d5ecf2e8
by Rodrigo Mesquita at 2025-09-12T17:57:25-04:00
ghc-toolchain: Make "Support SMP" a query on a Toolchain.Target
"Support SMP" is merely a function of target, so we can represent it as
such in `ghc-toolchain`.
Hadrian queries the Target using this predicate to determine how to
build GHC, and GHC queries the Target similarly to report under --info
whether it "Support SMP"
Towards #26227
-
e07b031a
by Rodrigo Mesquita at 2025-09-12T17:57:25-04:00
ghc-toolchain: Make "tgt rts linker only supports shared libs" function on Target
Just like with "Support SMP", "target RTS linker only supports shared
libraries" is a predicate on a `Target` so we can just compute it when
necessary from the given `Target`.
Towards #26227
-
14123ee6
by Simon Peyton Jones at 2025-09-12T17:58:07-04:00
Solve forall-constraints via an implication, again
In this earlier commit:
commit 953fd8f1dc080f1c56e3a60b4b7157456949be29
Author: Simon Peyton Jones <simon.peytonjones@gmail.com>
Date: Mon Jul 21 10:06:43 2025 +0100
Solve forall-constraints immediately, or not at all
I used a all-or-nothing strategy for quantified constraints
(aka forall-constraints). But alas that fell foul of #26315,
and #26376.
So this MR goes back to solving a quantified constraint by
turning it into an implication; UNLESS we are simplifying
constraints from a SPECIALISE pragma, in which case the
all-or-nothing strategy is great. See:
Note [Solving a Wanted forall-constraint]
Other stuff in this MR:
* TcSMode becomes a record of flags, rather than an enumeration
type; much nicer.
* Some fancy footwork to avoid error messages worsening again
(The above MR made them better; we want to retain that.)
See `GHC.Tc.Errors.Ppr.pprQCOriginExtra`.
-------------------------
Metric Decrease:
T24471
-------------------------
-
e6c192e2
by Simon Peyton Jones at 2025-09-12T17:58:07-04:00
Add a test case for #26396
...same bug ast #26315
-
8f3d80ff
by Luite Stegeman at 2025-09-13T08:43:09+02:00
Use mkVirtHeapOffsets for reconstructing terms in RTTI
This makes mkVirtHeapOffsets the single source of truth for
finding field offsets in closures.
-
eb389338
by Luite Stegeman at 2025-09-13T08:43:09+02:00
Sort non-pointer fields by size for more efficient packing
This sorts non-pointer fields in mkVirtHeapOffsets, always
storing the largest field first. The relative order of
equally sized fields remains unchanged.
This reduces wasted padding/alignment space in closures with
differently sized fields.
-
99b233f4
by Alison at 2025-09-13T16:51:04-04:00
ghc-heap: Fix race condition with profiling builds
Apply the same fix from Closures.hs (64fd0fac83) to Heap.hs by adding
empty imports to make way-dependent dependencies visible to `ghc -M`.
Fixes #15197, #26407
-
77deaa7a
by Cheng Shao at 2025-09-14T21:29:45-04:00
hadrian: build in-tree gmp with -fvisibility=hidden
When hadrian builds in-tree gmp, it should build the shared objects
with -fvisibility=hidden. The gmp symbols are only used by bignum
logic in ghc-internal and shouldn't be exported by the ghc-internal
shared library. We should always strive to keep shared library symbol
table lean, which benefits platforms with slow dynamic linker or even
hard limits about how many symbols can be exported (e.g. macos dyld,
win32 dll and wasm dyld).
-
42a18960
by Cheng Shao at 2025-09-14T21:30:26-04:00
Revert "wasm: add brotli compression for ghci browser mode"
This reverts commit 731217ce68a1093b5f9e26a07d5bd2cdade2b352.
Benchmarks show non-negligible overhead when browser runs on the same
host, which is the majority of actual use cases.
-
e6755b9f
by Cheng Shao at 2025-09-14T21:30:26-04:00
wasm: remove etag logic in ghci browser mode web server
This commit removes the etag logic in dyld script's ghci browser mode
web server. It was meant to support caching logic of wasm shared
libraries, but even if the port is manually specified to make caching
even relevant, for localhost the extra overhead around etag logic is
simply not worth it according to benchmarks.
-
ac5859b9
by sheaf at 2025-09-16T14:58:38-04:00
Add 'Outputable Natural' instance
This commit adds an Outputable instance for the Natural natural-number type,
as well as a "natural :: Natural -> SDoc" function that mirrors the existing
"integer" function.
-
d48ebc23
by Cheng Shao at 2025-09-16T14:59:18-04:00
autoconf: emit warning instead of error for FIND_PYTHON logic
This patch makes FIND_PYTHON logic emit warning instead of error, so
when the user doesn't expect to run the testsuite driver (especially
when installing a bindist), python would not be mandatory. Fixes #26347.
-
54b5950e
by Sylvain Henry at 2025-09-17T04:45:18-04:00
Print fully qualified unit names in name mismatch
It's more user-friendly to directly print the right thing instead of
requiring the user to retry with the additional `-dppr-debug` flag.
-
403cb665
by Ben Gamari at 2025-09-17T04:46:00-04:00
configure: Fix consistency between distrib and source CC check
Previously distrib/configure.ac did not
include `cc`.
Closes #26394.
-
2dcd4cb9
by Oleg Grenrus at 2025-09-17T04:46:41-04:00
Use isPrint in showUnique
The comment say
```
-- Avoid emitting non-printable characters in pretty uniques. See #25989.
```
so let the code do exactly that.
There are tags (at least : and 0 .. 9) which weren't in A .. z range.
-
e5dd754b
by Oleg Grenrus at 2025-09-17T04:46:42-04:00
Shorten in-module links in hyperlinked source
Instead of href="This.Module#ident" to just "#ident"
-
63189b2c
by Oleg Grenrus at 2025-09-17T04:46:42-04:00
Use showUnique in internalAnchorIdent
Showing the key of Unique as a number is generally not a great idea.
GHC Unique has a tag in high bits, so the raw number is unnecessarily
big.
So now we have
```html
<a href="#l-rvgK"><span class="hs-identifier hs-var hs-var">bar</span></a>
```
instead of
```html
<a href="#local-6989586621679015689"><span class="hs-identifier hs-var hs-var">bar</span></a>
```
Together with previous changes of shorter intra-module links the effect
on compressed files is not huge, that is expected as we simply remove
repetitive contents which pack well.
```
12_694_206 Agda-2.9.0-docs-orig.tar.gz
12_566_065 Agda-2.9.0-docs.tar.gz
```
However when unpacked, the difference can be significant,
e.g. Agda's largest module source got 5% reduction:
```
14_230_117 Agda.Syntax.Parser.Parser.html
13_422_109 Agda.Syntax.Parser.Parser.html
```
The whole hyperlinked source code directory got similar reduction
```
121M Agda-2.9.0-docs-orig/src
114M Agda-2.9.0-docs/src
```
For the reference, sources are about 2/3 of the generated haddocks
```
178M Agda-2.9.0-docs-old
172M Agda-2.9.0-docs
```
so we get around 3.5% size reduction overall. Not bad for a small local
changes.
-
6f63f57b
by Stefan Schulze Frielinghaus at 2025-09-17T04:47:22-04:00
rts: Fix alignment for gen_workspace #26334
After a0fa4941903272c48b050d24e93eec819eff51bd bootstrap is broken on
s390x and errors out with
rts/sm/GCThread.h:207:5: error:
error: alignment of array elements is greater than element size
207 | gen_workspace gens[];
| ^~~~~~~~~~~~~
The alignment constraint is applied via the attribute to the type
gen_workspace and leaves the underlying type struct gen_workspace_
untouched. On Aarch64, x86, and s390x the struct has a size of 128
bytes. On Aarch64 and x86 the alignments of 128 and 64 are divisors of
the size, respectively, which is why the type is a viable member type
for an array. However, on s390x, the alignment is 256 and therefore is
not a divisor of the size and hence cannot be used for arrays.
Basically I see two fixes here. Either decrease the alignment
requirement on s390x, or by applying the alignment constraint on the
struct itself. The former might affect performance as noted in
a0fa4941903272c48b050d24e93eec819eff51bd. The latter introduces padding
bits whenever necessary in order to ensure that
sizeof(gen_workspace[N])==N*sizeof(gen_workspace) holds which is done by
this patch.
-
06d25623
by Cheng Shao at 2025-09-17T19:32:27-04:00
ghci: add :shell command
This patch adds a new :shell command to ghci which works similarly to
:!, except it guarantees to run the command via sh -c. On POSIX hosts
the behavior is identical to :!, but on Windows it uses the msys2
shell instead of system cmd.exe shell. This is convenient when writing
simple ghci scripts that run simple POSIX commands, and the behavior
can be expected to be coherent on both Windows and POSIX.
Co-authored-by: Codex <codex@openai.com>
-
186054f7
by Cheng Shao at 2025-09-17T19:32:27-04:00
testsuite: remove legacy :shell trick
This commit makes use of the built-in :shell functionality in ghci in
the test cases, and remove the legacy :shell trick.
-
0a3a4aa3
by Cheng Shao at 2025-09-17T19:32:27-04:00
docs: document :shell in ghci
This commit documents the :shell command in ghci.
Co-authored-by: Codex <codex@openai.com>
-
a4ff12bb
by Cheng Shao at 2025-09-17T19:33:09-04:00
ghc-internal: fix codepages program
codepages was not properly updated during the base -> ghc-internal
migration, this commit fixes it.
-
7e094def
by Cheng Shao at 2025-09-17T19:33:09-04:00
ghc-internal: relax ucd2haskell cabal upper bounds
This commit relaxes ucd2haskell cabal upper bounds to make it runnable
via ghc 9.12/9.14.
-
7077c9f7
by Cheng Shao at 2025-09-17T19:33:09-04:00
ghc-internal: update to unicode 17.0.0
This commit updates the generated code in ghc-internal to match
unicode 17.0.0.
-
cef8938f
by sheaf at 2025-09-17T19:34:09-04:00
Bad record update msg: allow out-of-scope datacons
This commit ensures that, when we encounter an invalid record update
(because no constructor exists which contains all of the record fields
mentioned in the record update), we graciously handle the situation in
which the constructors themselves are not in scope. In that case,
instead of looking up the constructors in the GlobalRdrEnv, directly
look up their GREInfo using the lookupGREInfo function.
Fixes #26391
-
a2d9d7c2
by sheaf at 2025-09-17T19:34:09-04:00
Improve Notes about disambiguating record updates
This commit updates the notes [Disambiguating record updates] and
[Type-directed record disambiguation], in particular adding more
information about the deprecation status of type-directed disambiguation
of record updates.
-
de44e69e
by sheaf at 2025-09-19T05:16:51-04:00
Enable TcM plugins in initTc
This commit ensures that we run typechecker plugins and defaulting
plugins whenever we call initTc.
In particular, this ensures that the pattern-match checker, which calls
'initTcDsForSolver' which calls 'initTc', runs with typechecker plugins
enabled. This matters for situations like:
merge :: Vec n a -> Vec n a -> Vec (2 * n) a
merge Nil Nil = Nil
merge (a <: as) (b <: bs) = a :< (b <: merge as bs)
in which we need the typechecker plugin to run in order to tell us that
the Givens would be inconsistent in the additional equation
merge (_ <: _) Nil
and thus that the equation is not needed.
Fixes #26395
-
2c378ad2
by Cheng Shao at 2025-09-19T05:17:33-04:00
rel-eng: update fedora image to 42
This patch is a part of #25876 and updates fedora image to 42.
-
0a9d9ffc
by Sylvain Henry at 2025-09-19T13:12:14-04:00
Fix output of T14999 (#23685)
Fix output of T14999 to:
- take into account the +1 offset to DW_AT_low_pc (see Note [Info Offset])
- always use Intel's syntax to force consistency: it was reported that
sometimes GDB prints `jmpq` instead of `jmp` with the AT&T syntax
-
1480872a
by Vladislav Zavialov at 2025-09-19T13:12:54-04:00
Fix PREP_MAYBE_LIBRARY in prep_target_file.m4
This change fixes a configure error introduced in:
commit 8235dd8c4945db9cb03e3be3c388d729d576ed1e
ghc-toolchain: Move UseLibdw to per-Target file
Now the build no longer fails with:
acghc-toolchain: Failed to read a valid Target value from hadrian/cfg/default.target
-
d1d9e39e
by Ben Gamari at 2025-09-19T18:24:52-04:00
StgToByteCode: Don't assume that data con workers are nullary
Previously StgToByteCode assumed that all data-con workers were of a
nullary representation. This is not a valid assumption, as seen
in #23210, where an unsaturated application of a unary data
constructor's worker resulted in invalid bytecode. Sadly, I have not yet
been able to reduce a minimal testcase for this.
Fixes #23210.
-
3eeecd50
by Ben Gamari at 2025-09-19T18:24:53-04:00
testsuite: Mark T23146* as unbroken
-
2e73f342
by sheaf at 2025-09-19T18:24:53-04:00
Add test for #26216
-
c2efb912
by Sven Tennie at 2025-09-19T18:25:36-04:00
Generate correct test header
This increases convenience when copying & pasting...
-
d2fb811e
by Sven Tennie at 2025-09-19T18:25:36-04:00
foundation test: Fix shift amount (#26248)
Shift primops' results are only defined for shift amounts of 0 to word
size - 1. The approach is similar to testing div-like operations (which
have a constraint regarding zero operands.)
This was partly vibe coded (https://github.com/supersven/ghc/pull/1) but
then heavily refactored.
-
a62ce115
by Andreas Klebinger at 2025-09-19T18:26:18-04:00
Tweak jspace test
I've given it a longer timeout, and tweaked the test file generation
to speed it up a bit. Hopefully that is enough to make it constentily pass.
Last but not least it now also always uses three threads.
-
0f034942
by Cheng Shao at 2025-09-19T18:26:59-04:00
rts: remove obsolete CC_SUPPORTS_TLS logic
This patch removes obsolete CC_SUPPORTS_TLS logic throughout the rts,
given __thread is now uniformly supported by C toolchains of all
platforms we currently support.
-
ef705655
by Cheng Shao at 2025-09-19T18:27:41-04:00
rts: remove obsolete HAS_VISIBILITY_HIDDEN logic
This patch removes obsolete HAS_VISIBILITY_HIDDEN logic throughout the
rts, given __attribute__((visibility("hidden"))) is uniformly
supported by C toolchains of all platforms we currently support.
-
9fdc1f7d
by Cheng Shao at 2025-09-19T18:28:21-04:00
rts: remove -O3 pragma hack in Hash.c
This patch removes an obsolete gcc pragma to specify -O3 in Hash.c.
Hadrian already passes the right flag.
-
b8cfa8f7
by Cheng Shao at 2025-09-19T18:29:01-04:00
rts: remove obsolete COMPILING_WINDOWS_DLL logic
This patch removes obsolete COMPILING_WINDOWS_DLL logic throughout the
rts. They were once used for compiling to win32 DLLs, but we haven't
been able to compile Haskell units to win32 DLLs for many years now,
due to PE format's restriction of no more than 65536 exported symbols
in a single DLL.
-
bb760611
by Cheng Shao at 2025-09-19T18:29:42-04:00
wasm: bump browser_wasi_shim to 0.4.2
This patch bumps the browser_wasi_shim dependency of wasm dyld script
to 0.4.2.
-
8b0940db
by Cheng Shao at 2025-09-20T06:48:05-04:00
compiler: move Binary instance of Map to GHC.Utils.Binary
This patch moves `Binary` instance of `Map` from `haddock-api` to
`GHC.Utils.Binary`. This also allows us to remove a redundant instance
defined for `NameEntityInfo`, which is a type synonym for `Map`.
-
4a8fed75
by Vladislav Zavialov at 2025-09-20T06:48:47-04:00
Fix keyword in ExplicitNamespaces error message (#26418)
Consider this module header and the resulting error:
{-# LANGUAGE NoExplicitNamespaces #-}
module T26418 (data HeadC) where
-- error: [GHC-47007]
-- Illegal keyword 'type'
Previously, the error message would mention 'type' (as shown above),
even though the user wrote 'data'. This has now been fixed.
The error location has also been corrected: it is now reported at the
keyword position rather than at the position of the associated
import/export item.
-
867c2675
by Cheng Shao at 2025-09-20T06:49:28-04:00
wasm: fix dyld handling for forward declared GOT.func items
This patch fixes wasm shared linker's handling of forward declared
GOT.func items, see linked issue for details. Also adds T26430 test to
witness the fix. Fixes #26430.
Co-authored-by: Codex <codex@openai.com>
-
e7df6cc0
by Simon Peyton Jones at 2025-09-23T14:34:39-04:00
Improve pretty printer for HsExpr
Given a very deeply-nested application, it just kept printing
deeper and deeper. This small change makes it cut off.
Test is in #26330, but we also get a dramatic decrease in compile
time for perf/compiler/InstanceMatching:
InstanceMatching 4,086,884,584 1,181,767,232 -71.1% GOOD
Why? Because before we got a GIGANTIC error message that took
ages to pretty-print; now we get this much more civilised message
(I have removed some whitespace.)
Match.hs:1007:1: error:
• No instance for ‘Show (F001 a)’ arising from a use of ‘showsPrec’
• In the second argument of ‘showString’, namely
‘(showsPrec
11 b1
(GHC.Internal.Show.showSpace
(showsPrec
11 b2
(GHC.Internal.Show.showSpace
(showsPrec
11 b3
(GHC.Internal.Show.showSpace
(showsPrec
11 b4
(GHC.Internal.Show.showSpace
(showsPrec
11 b5
(GHC.Internal.Show.showSpace
(showsPrec
11 b6
(GHC.Internal.Show.showSpace (showsPrec ...)))))))))))))’
-----------------------
The main payload is
* At the start of `pprExpr`
* In the defn of `pprApp`
A little bit of refactoring:
* It turned out that we were setting the default cut-off depth to a
fixed value in two places, so changing one didn't change the other.
See defaultSDocDepth and defaultSDocCols
* I refactored `pprDeeperList` a bit so I could understand it better.
Because the depth calculation has changed, there are lots of small
error message wibbles.
Metric Decrease:
InstanceMatching
-
209f0158
by Simon Peyton Jones at 2025-09-23T14:34:39-04:00
Use Outputable.ellipsis rather than text "..."
-
64bb0e37
by Sylvain Henry at 2025-09-23T14:35:56-04:00
deriveConstants: automatically pass -fcommon CC flag (#26393)
By mistake we tried to use deriveConstants without passing
`--gcc-flag -fcommon` (which Hadrian does) and it failed.
This patch:
1. adds parsing support for constants stored in the .bss section (i.e.
when -fcommon isn't passed)
2. enables passing `-fcommon` automatically to the C compiler because
Windows requires this for subtle reasons
3. Documents the subtle reasons
(1) isn't strictly necessary because we always do (2) but it does no
harm and it is still useful if the CC flags ever contain -fno-common
-
afcdf92f
by Oleg Grenrus at 2025-09-23T14:36:41-04:00
Don't wrap spaces in <span>s
Doing similar comparison as in 63189b2ceca07edf4e179f4180ca60d470c62cb3
With this change the gzipped documentation is now 2% smaller (previously 1%)
12_694_206 Agda-2.9.0-docs-orig.tar.gz
12_436_829 Agda-2.9.0-docs.tar.gz
Unzipped docs are 5% smaller (previously 3%)
178M Agda-2.9.0-docs-orig
169M Agda-2.9.0-docs
Individual hyperlinked sources are around 7-10% smaller (previously 5%)
(`Parser` module is generated by happy and has relatively little whitespace)
14_230_117 Agda.Syntax.Parser.Parser.html
13_220_758 Agda.Syntax.Parser.Parser.html
Agda's hyperlinked sources are 9% smaller now:
121M Agda-2.9.0-docs-orig/src
110M Agda-2.9.0-docs/src
-
67de53a6
by Cheng Shao at 2025-09-23T14:37:31-04:00
rts: remove obsolete __GNUC__ related logic
This patch removes obsolete `__GNUC__` related logic, given on any
currently supported platform and toolchain, `__GNUC__ >= 4` is
universally true. Also pulls some other weeds and most notably, use
`__builtin___clear_cache` for clang as well, since clang has supported
this gcc intrinsic since 2014, see
https://github.com/llvm/llvm-project/commit/c491a8d4577052bc6b3b4c72a7db6a7cfcbc2ed0.
-
c4d32493
by Sven Tennie at 2025-09-23T20:40:57-04:00
RV64: Fix: Add missing truncation to MO_S_Shr (#26248)
Sub-double word (<W64) registers need to be truncated after the
operation.
-
41dce477
by Sven Tennie at 2025-09-23T20:40:57-04:00
RV64: Cleanup shift emitting cases/code
Remove overlapping cases to make the shift logic easier to understand.
-
0a601c30
by Alex Washburn at 2025-09-23T20:41:41-04:00
Correcting LLVM linking of Intel BMI intrinsics pdep{8,16} and pext{8,16}.
This patch fixes #26065.
The LLVM interface does not expose bindings to:
- llvm.x86.bmi.pdep.8
- llvm.x86.bmi.pdep.16
- llvm.x86.bmi.pext.8
- llvm.x86.bmi.pext.16
So calls are instead made to llvm.x86.bmi.{pdep,pext}.32 in these cases,
with pre/post-operation truncation to constrain the logical value range.
-
89e8ff3d
by Peng Fan at 2025-09-23T20:42:37-04:00
NCG/LA64: Implement MO_BSwap and MO_BRev with bit-manipulation Instructions
-
50f6be09
by Sylvain Henry at 2025-09-23T20:43:29-04:00
Allow Core plugins to access unoptimized Core (#23337)
Make the first simple optimization pass after desugaring a real CoreToDo
pass. This allows CorePlugins to decide whether they want to be executed
before or after this pass.
-
30ef0aac
by Simon Hengel at 2025-09-23T20:44:12-04:00
docs: Fix typo in scoped_type_variables.rst
-
f8919262
by Cheng Shao at 2025-09-23T20:44:54-04:00
ghci: fix bootstrapping with 9.12.3-rc1 and above
This patch fixes bootstrapping GHC with 9.12.3-rc1 and above. ghci
defines `Binary` instance for `HalfWord` in `ghc-heap`, which is a
proper `newtype` in 9.14 and starting from 9.12.3. Given we don't
build `ghc-heap` in stage0, we need to fix this predicate so that it
corresponds to the boot ghc versions that contain the right version of
`ghc-heap`.
-
a7f15858
by sheaf at 2025-09-24T09:49:53-04:00
User's guide: clarify optimisation of INLINABLE unfoldings
This updates the user's guide section on INLINABLE pragmas to explain how
the unfoldings of inlineable functions are optimised. The user's guide incorrectly
stated that the RHS was not optimised at all, but this is not true. Instead, GHC
is careful about phase control to optmise the RHS while retaining the guarantee
that GHC behaves as if the original RHS had been written.
-
495886d9
by Rodrigo Mesquita at 2025-09-24T09:50:35-04:00
cleanup: Delete historical artifact of COMPILING_WINDOWS_DLL
Namely, drop the obsolete
- DLL_IMPORT_RTS
- DLL_IMPORT_DATA_VAR
- DLL_IMPORT_DATA_VARNAME
- DLL_IMPORT_DATA_REF
These macros were not doing anything and placed inconsistently
Looking at the git logs reveal these macros were used to support
dynamic libraries on Win32, a feature that was dropped
in b8cfa8f741729ef123569fb321c4b2ab4a1a941c
This allows us to get rid of the rts/DLL.h file too.
-
5ae89054
by Sylvain Henry at 2025-09-24T17:07:00-04:00
Allow disabling builtin rules (#20298)
Add a way to disable built-in rules programmatically and with a debug flag.
I also took the opportunity to add a debug flag to disable bignum rules,
which was only possible programmatically (e.g. in a plugin).
-
135242ca
by Rodrigo Mesquita at 2025-09-24T17:07:44-04:00
Don't use build CFLAGS and friends as target settings
In the GHC in tree configure, `CFLAGS`, `CXXFLAGS`, and similar tool
configuration flags apply to the BUILD phase of the compiler, i.e. to
the tools run to compile GHC itself.
Notably, they should /not/ be carried over to the Target settings, i.e.
these flags should /not/ apply to the tool which GHC invokes at runtime.
Fixes #25637
-
b418408b
by Irene Knapp at 2025-09-25T09:47:54-04:00
Document etymology of "bind" as the name for `>>=`
It took me twenty years of contemplation to realize why it's called that.
I therefore feel that it may not be obvious to beginners.
-
e9c5e46f
by Brandon Chinn at 2025-09-25T09:48:36-04:00
Fix tabs in string gaps (#26415)
Tabs in string gaps were broken in bb030d0d because previously, string gaps were manually parsed, but now it's lexed by the usual Alex grammar and post-processed after successful lexing.
It broke because of a discrepancy between GHC's lexer grammar and the Haskell Report. The Haskell Report includes tabs in whitechar:
whitechar → newline | vertab | space | tab | uniWhite
$whitechar used to include tabs until 18 years ago, when it was removed in order to exclude tabs from $white_no_nl in order to warn on tabs: 6e202120. In this MR, I'm adding \t back into $whitechar, and explicitly excluding \t from the $white_no_nl+ rule ignoring all whitespace in source code, which more accurately colocates the "ignore all whitespace except tabs, which is handled in the next line" logic.
As a side effect of this MR, tabs are now allowed in pragmas; currently, a pragma written as {-# \t LANGUAGE ... #-} is interpreted as the tab character being the pragma name, and GHC warns "Unrecognized pragma". With this change, tabs are ignored as whitespace, which more closely matches the Report anyway.
-
8bf5b309
by Cheng Shao at 2025-09-25T09:49:18-04:00
wasm: remove the --no-turbo-fast-api-calls hack from dynamic linker shebang
This patch removes the `--no-turbo-fast-api-calls` hack from the dyld
script shebang; it was used to workaround v8 fast call coredumps in
nodejs and no longer needed, and comes with a performance penalty,
hence the removal.
-
c1cab0c3
by Sylvain Henry at 2025-09-26T10:36:30-04:00
Revert "Add necessary flag for js linking"
This reverts commit 84f68e2231b2eddb2e1dc4e90af394ef0f2e803f.
This commit didn't have the expected effect. See discussion in #26290.
Instead we export HEAP8 and HEAPU8 from rts/js/mem.js
-
0a434a80
by Sylvain Henry at 2025-09-26T10:36:30-04:00
JS: export HEAPU8 (#26290)
This is now required by newer Emscripten versions.
-
b10296a9
by Andreas Klebinger at 2025-09-26T10:37:11-04:00
sizeExpr: Improve Tick handling.
When determining if we scrutinize a function argument we
now properly look through ticks. Fixes #26444.
-
d9e2a9a7
by mniip at 2025-09-26T16:00:50-04:00
rts: Refactor parsing of -h flags
We have a nontrivial amount of heap profiling flags available in the
non-profiled runtime, so it makes sense to reuse the parsing code
between the profiled and the non-profiled runtime, only restricting
which flags are allowed.
-
089e45aa
by mniip at 2025-09-26T16:00:50-04:00
rts: Fix parsing of -h options with braces
When the "filter by" -h options were introduced in
bc210f7d267e8351ccb66972f4b3a650eb9338bb, the braces were mandatory.
Then in 3c22fb21fb18e27ce8d941069a6915fce584a526, the braces were made
optional. Then in d1ce35d2271ac8b79cb5e37677b1a989749e611c the brace
syntax stopped working, and no one seems to have noticed.
-
423f1472
by mniip at 2025-09-26T16:00:50-04:00
rts: add -hT<type> and -hi<table id> heap filtering options (#26361)
They are available in non-profiled builds.
Along the way fixed a bug where combining -he<era> and -hr<retainer>
would ignore whether the retainer matches or not.
-
4cda4785
by mniip at 2025-09-26T16:00:50-04:00
docs: Document -hT<type> and -hi<addr>
-
982ad30f
by mniip at 2025-09-26T16:00:50-04:00
rts: Refactor dumping the heap census
Always do the printing of the total size right next to where the bucket
label is printed. This prevents accidentally printing a label without
the corresponding amount.
Fixed a bug where exactly this happened for -hi profile and the 0x0
(uncategorized) info table.
There is now also much more symmetry between fprintf(hp_file,...) and
the corresponding traceHeapProfSampleString.
-
8cbe006a
by Cheng Shao at 2025-09-26T16:01:34-04:00
hadrian: fix GHC.Platform.Host generation for cross stage1
This patch fixes incorrectly GHC.Platform.Host generation logic for
cross stage1 in hadrian (#26449). Also adds T26449 test case to
witness the fix.
Co-authored-by: Codex <codex@openai.com>
-
0ddd0fdc
by soulomoon at 2025-09-28T19:24:10-04:00
Remove hptAllInstances usage during upsweep
Previously, during the upsweep phase when
checking safe imports, we were loading the module
interface with runTcInteractive, which in turn calls
hptAllInstances. This accesses non-below modules
from the home package table.
Change the implementation of checkSafeImports
to use initTcWithGbl and loadSysInterface to load the
module interface, since we already have TcGblEnv at hand.
This eliminates the unnecessary use of runTcInteractive
and hptAllInstances during the upsweep phase.
-
e05c496c
by Ben Gamari at 2025-09-28T19:24:59-04:00
base: Update changelog to reflect timing of IOPort# removal
This change will make 9.14 afterall.
-
bdc9d130
by Cheng Shao at 2025-09-28T19:25:45-04:00
rts: fix wasm JSFFI initialization constructor code
This commit fixes wasm JSFFI initialization constructor code so that
the constructor is self-contained and avoids invoking a fake
__main_argc_argv function. The previous approach of reusing
__main_void logic in wasi-libc saves a tiny bit of code, at the
expense of link-time trouble whenever GHC links a wasm module without
-no-hs-main, in which case the driver-generated main function would
clash with the definition here, resulting in a linker error. It's
simply better to avoid messing with the main function, and it would
additionally allow linking wasm32-wasi command modules that does make
use of synchronous JSFFI.
-
5d59fc8f
by Cheng Shao at 2025-09-28T19:26:27-04:00
rts: provide stub implementations of ExecPage functions for wasm
This patch provides stub implementations of ExecPage functions for
wasm. They are never actually invoked at runtime for any non-TNTC
platform, yet they can cause link-time errors of missing symbols when
the GHCi.InfoTable module gets linked into the final wasm module (e.g.
a GHC API program).
-
a4d664c7
by Cheng Shao at 2025-09-29T17:29:22+02:00
compiler/ghci: replace the LoadDLL message with LoadDLLs
As a part of #25407, this commit changes the LoadDLL message to
LoadDLLs, which takes a list of DLL paths to load and returns the list
of remote pointer handles. The wasm dyld is refactored to take
advantage of LoadDLLs and harvest background parallelism. On other
platforms, LoadDLLs is based on a fallback codepath that does
sequential loading.
The driver is not actually emitting singular LoadDLLs message with
multiple DLLs yet, this is left in subsequent commits.
Co-authored-by: Codex <codex@openai.com>
-
c7fc4bae
by Cheng Shao at 2025-09-29T17:29:22+02:00
driver: separate downsweep/upsweep phase in loadPackages'
This commit refactors GHC.Linker.Loader.loadPackages' to be separated
into downsweep/upsweep phases:
- The downsweep phase performs dependency analysis and generates a
list of topologically sorted packages to load
- The upsweep phase sequentially loads these packages by calling
loadPackage
This is a necessary refactoring to make it possible to make loading of
DLLs concurrent.
-
ab180104
by Cheng Shao at 2025-09-29T17:57:19+02:00
driver: emit single LoadDLLs message to load multiple DLLs
This commit refactors the driver so that it emits a single LoadDLLs
message to load multiple DLLs in GHC.Linker.Loader.loadPackages'.
Closes #25407.
-------------------------
Metric Increase:
MultiLayerModulesTH_OneShot
TcPlugin_RewritePerf
-------------------------
Co-authored-by: Codex <codex@openai.com>
-
9c304ec0
by Sean D. Gillespie at 2025-09-29T19:57:07-04:00
Fix SIZED_BIN_OP_TY_INT casts in RTS interpreter
Correct `SIZED_BIN_OP_TY_INT` cast to integer. Previously, it cast
its second operand as its parameter `ty`. This does not currently
cause any issues, since we are only using it for bit shifts.
Fixes #26287
-
a1de535f
by Luite Stegeman at 2025-09-30T18:40:28-04:00
rts: Fix lost wakeups in threadPaused for threads blocked on black holes
The lazy blackholing code in threadPaused could overwrite closures
that were already eagerly blackholed, and as such wouldn't have a
marked update frame. If the black hole was overwritten by its
original owner, this would lead to an undetected collision, and
the contents of any existing blocking queue being lost.
This adds a check for eagerly blackholed closures and avoids
overwriting their contents.
Fixes #26324
-
b7e21e49
by Luite Stegeman at 2025-09-30T18:40:28-04:00
rts: push the correct update frame in stg_AP_STACK
The frame contains an eager black hole (__stg_EAGER_BLACKHOLE_info) so
we should push an stg_bh_upd_frame_info instead of an stg_upd_frame_info.
-
02a7c18a
by Cheng Shao at 2025-09-30T18:41:27-04:00
ghci: fix lookupSymbolInDLL behavior on wasm
This patch fixes lookupSymbolInDLL behavior on wasm to return Nothing
instead of throwing. On wasm, we only have lookupSymbol, and the
driver would attempt to call lookupSymbolInDLL first before falling
back to lookupSymbol, so lookupSymbolInDLL needs to return Nothing
gracefully for the fallback behavior to work.
-
aa0ca5e3
by Cheng Shao at 2025-09-30T18:41:27-04:00
hadrian/compiler: enable internal-interpreter for ghc library in wasm stage1
This commit enables the internal-interpreter flag for ghc library in
wasm stage1, as well as other minor adjustments to make it actually
possible to launch a ghc api session that makes use of the internal
interpreter. Closes #26431 #25400.
-
69503668
by Cheng Shao at 2025-09-30T18:41:27-04:00
testsuite: add T26431 test case
This commit adds T26431 to testsuite/tests/ghci-wasm which goes
through the complete bytecode compilation/linking/running pipeline in
wasm, so to witness that the ghc shared library in wasm have full
support for internal-interpreter.
-
e9445c01
by Matthew Pickering at 2025-09-30T18:42:23-04:00
driver: Load bytecode static pointer entries during linking
Previously the entries were loaded too eagerly, during upsweep, but we
should delay loading them until we know that the relevant bytecode
object is demanded.
Towards #25230
-
b8307eab
by Cheng Shao at 2025-09-30T18:43:14-04:00
autoconf/ghc-toolchain: remove obsolete C99 check
This patch removes obsolete c99 check from autoconf/ghc-toolchain. For
all toolchain & platform combination we support, gnu11 or above is
already supported without any -std flag required, and our RTS already
required C11 quite a few years ago, so the C99 check is completely
pointless.
-
9c293544
by Simon Peyton Jones at 2025-10-01T09:36:10+01:00
Fix buglet in GHC.Core.Unify.uVarOrFam
We were failing to match two totally-equal types!
This led to #26457.
-
554487a7
by Rodrigo Mesquita at 2025-10-01T23:04:43-04:00
cleanup: Drop obsolete comment about HsConDetails
HsConDetails used to have an argument representing the type of the
tyargs in a list:
data HsConDetails tyarg arg rec
= PrefixCon [tyarg] [arg]
This datatype was shared across 3 synonyms: HsConPatDetails,
HsConDeclH98Details, HsPatSynDetails. In the latter two cases, `tyarg`
was instanced to `Void` meaning the list was always empty for these
cases.
In 7b84c58867edca57a45945a20a9391724db6d9e4, this was refactored such
that HsConDetails no longer needs a type of tyargs by construction. The
first case now represents the type arguments in the args type itself,
with something like:
ConPat "MkE" [InvisP tp1, InvisP tp2, p1, p2]
So the deleted comment really is just obsolete.
Fixes #26461
-
6992ac09
by Cheng Shao at 2025-10-02T07:27:55-04:00
testsuite: remove unused expected output files
This patch removes unused expected output files in the testsuites on
platforms that we no longer support.
-
39eaaaba
by Ben Gamari at 2025-10-02T07:28:45-04:00
rts: Dynamically initialize built-in closures
To resolve #26166 we need to eliminate references to undefined symbols
in the runtime system. One such source of these is the runtime's
static references to `I#` and `C#` due the `stg_INTLIKE` and
`stg_CHARLIKE` arrays.
To avoid this we make these dynamic, initializing them during RTS
start-up.
-
c254c54b
by Cheng Shao at 2025-10-02T07:29:33-04:00
compiler: only invoke keepCAFsForGHCi if internal-interpreter is enabled
This patch makes the ghc library only invoke keepCAFsForGHCi if
internal-interpreter is enabled. For cases when it's not (e.g. the
host build of a cross ghc), this avoids unnecessarily retaining all
CAFs in the heap. Also fixes the type signature of c_keepCAFsForGHCi
to match the C ABI.
-
c9ec4d43
by Simon Hengel at 2025-10-02T18:42:20-04:00
Update copyright in documentation
-
da9633a9
by Matthew Pickering at 2025-10-02T18:43:04-04:00
loader: Unify loadDecls and loadModuleLinkables functions
These two functions nearly did the same thing. I have refactored them so
that `loadDecls` now calls `loadModuleLinkables`.
Fixes #26459
-
5db98d80
by Simon Hengel at 2025-10-02T18:43:53-04:00
Fix typo
-
1275d360
by Matthew Pickering at 2025-10-03T06:05:56-04:00
testsuite: Use ghci_ways to set ways in PackedDataCon/UnboxedTuples/UnliftedDataTypeInterp tests
These tests reimplemented the logic from `valid_way` in order to
determine what ways to run. It's easier to use this combination of
`only_ways` and `extra_ways` to only run in GHCi ways and always run in
GHCi ways.
-
c06b534b
by Matthew Pickering at 2025-10-03T06:06:40-04:00
Rename interpreterBackend to bytecodeBackend
This is preparation for creating bytecode files.
The "interpreter" is one way in which we can run bytecode objects. It is
more accurate to describe that the backend produces bytecode, rather
than the means by which the code will eventually run.
The "interpreterBackend" binding is left as a deprecated alias.
-
41bdb16f
by Andreas Klebinger at 2025-10-06T18:04:34-04:00
Add a perf test for #26425
-
1da0c700
by Andreas Klebinger at 2025-10-06T18:05:14-04:00
Testsuite: Silence warnings about Wx-partial in concprog001
-
7471eb6a
by sheaf at 2025-10-07T21:39:43-04:00
Improve how we detect user type errors in types
This commit cleans up all the code responsible for detecting whether a
type contains "TypeError msg" applications nested inside it. All the
logic is now in 'userTypeError_maybe', which is always deep. Whether
it looks inside type family applications is determined by the passed-in
boolean flag:
- When deciding whether a constraint is definitely insoluble, don't
look inside type family applications, as they may still reduce -- in
which case the TypeError could disappear.
- When reporting unsolved constraints, look inside type family
applications: they had the chance to reduce but didn't, and the
custom type error might contain valuable information.
All the details are explained in Note [Custom type errors in constraints]
in GHC.Tc.Types.Constraint.
Another benefit of this change is that it allows us to get rid of the
deeply dodgy 'getUserTypeErrorMsg' function.
This commit also improves the detection of custom type errors, for
example in equality constraints:
TypeError blah ~# rhs
It used to be the case that we didn't detect the TypeError on the LHS,
because we never considered that equality constraints could be insoluble
due to the presence of custom type errors. Addressing this oversight
improves detection of redundant pattern match warnings, fixing #26400.
-
29955267
by Rodrigo Mesquita at 2025-10-07T21:40:25-04:00
cleanup: Drop obsolete settings from config.mk.in
These values used to be spliced into the bindist's `config.mk` s.t. when
`make` was run, the values were read and written into the bindist installation `settings` file.
However, we now carry these values to the bindist directly in the
default.target toolchain file, and `make` writes almost nothing to
`settings` now (see #26227)
The entries deleted in this MR were already unused.
Fixes #26478
-
f7adfed2
by ARATA Mizuki at 2025-10-08T08:37:24-04:00
T22033 is only relevant if the word size is 64-bit
Fixes #25497
-
ff1650c9
by Ben Gamari at 2025-10-08T08:38:07-04:00
rts/posix: Enforce iteration limit on heap reservation logic
Previously we could loop indefinitely when attempting to get an address
space reservation for our heap. Limit the logic to 8 iterations to
ensure we instead issue a reasonable error message.
Addresses #26151.
-
01844557
by Ben Gamari at 2025-10-08T08:38:07-04:00
rts/posix: Hold on to low reservations when reserving heap
Previously when the OS gave us an address space reservation in low
memory we would immediately release it and try again. However, on some
platforms this meant that we would get the same allocation again in the
next iteration (since mmap's `hint` argument is just that, a hint).
Instead we now hold on to low reservations until we have found a
suitable heap reservation.
Fixes #26151.
-
b2c8d052
by Sven Tennie at 2025-10-08T08:38:47-04:00
Build terminfo only in upper stages in cross-builds (#26288)
Currently, there's no way to provide library paths for [n]curses for
both - build and target - in cross-builds. As stage0 is only used to
build upper stages, it should be fine to build terminfo only for them.
This re-enables building cross-compilers with terminfo.
-
c58f9a61
by Julian Ospald at 2025-10-08T08:39:36-04:00
ghc-toolchain: Drop `ld.gold` from merge object command
It's deprecated.
Also see #25716
-
2b8baada
by sheaf at 2025-10-08T18:23:37-04:00
Improvements to 'mayLookIdentical'
This commit makes significant improvements to the machinery that decides
when we should pretty-print the "invisible bits" of a type, such as:
- kind applications, e.g. '@k' in 'Proxy @k ty'
- RuntimeReps, e.g. 'TYPE r'
- multiplicities and linear arrows 'a %1 -> b'
To do this, this commit refactors 'mayLookIdentical' to return **which**
of the invisible bits don't match up, e.g. in
(a %1 -> b) ~ (a %Many -> b)
we find that the invisible bit that doesn't match up is a multiplicity,
so we should set 'sdocLinearTypes = True' when pretty-printing, and with
e.g.
Proxy @k1 ~ Proxy @k2
we find that the invisible bit that doesn't match up is an invisible
TyCon argument, so we set 'sdocPrintExplicitKinds = True'.
We leverage these changes to remove the ad-hoc treatment of linearity
of data constructors with 'dataConDisplayType' and 'dataConNonLinearType'.
This is now handled by the machinery of 'pprWithInvisibleBits'.
Fixes #26335 #26340
-
129ce32d
by sheaf at 2025-10-08T18:23:37-04:00
Store SDoc context in SourceError
This commits modifies the SourceError datatype which is used for
throwing and then reporting exceptions by storing all the info we need
to be able to print the SDoc, including whether we should print with
explicit kinds, explicit runtime-reps, etc.
This is done using the new datatype:
data SourceErrorContext
= SEC
!DiagOpts
!(DiagnosticOpts GhcMessage)
Now, when we come to report an error (by handling the exception), we
have access to the full context we need.
Fixes #26387
-
f9790ca8
by Ben Gamari at 2025-10-08T18:24:19-04:00
gitlab-ci: Make RELEASE_JOB an input
Rather than an undocumented variable.
-
14281a22
by Ben Gamari at 2025-10-11T14:06:47-04:00
rts/nonmoving: Fix comment spelling
-
bedd38b0
by Ben Gamari at 2025-10-11T14:06:47-04:00
rts/nonmoving: Use atomic operations to update bd->flags
-
215d6841
by Ben Gamari at 2025-10-11T14:06:47-04:00
nonmoving: Use get_itbl instead of explicit loads
This is cleaner and also fixes unnecessary (and unsound) use of
`volatile`.
-
2c94aa3a
by Ben Gamari at 2025-10-11T14:06:47-04:00
rts/Scav: Handle WHITEHOLEs in scavenge_one
`scavenge_one`, used to scavenge mutable list entries, may encounter
`WHITEHOLE`s when the non-moving GC is in use via two paths:
1. when an MVAR is being marked concurrently
2. when the object belongs to a chain of selectors being short-cutted.
Fixes #26204.
-
6bd8155c
by Matthew Pickering at 2025-10-11T14:07:29-04:00
Add support for generating bytecode objects
This commit adds the `-fwrite-byte-code` option which makes GHC emit a
`.gbc` file which contains a serialised representation of bytecode.
The bytecode can be loaded by the compiler to avoid having to
reinterpret a module when using the bytecode interpreter (for example,
in GHCi).
There are also the new options:
* -gbcdir=<DIR>: Specify the directory to place the gbc files
* -gbcsuf=<suffix>: Specify the suffix for gbc files
The option `-fbyte-code-and-object-code` now implies
`-fwrite-byte-code`.
These performance tests fail due to https://github.com/haskell/directory/issues/204
-------------------------
Metric Increase:
MultiComponentModules
MultiLayerModules
MultiComponentModulesRecomp
MultiLayerModulesRecomp
MultiLayerModulesTH_Make
MultiLayerModulesTH_OneShot
T13701
-------------------------
The bytecode serialisation part was implemented by Cheng Shao
Co-authored-by: Cheng Shao <terrorjack@type.dance>
-
dc8f9599
by Matthew Pickering at 2025-10-11T14:07:30-04:00
Revert "Add a perf test for #26425"
This test has a large memory spike currently, which makes the test
sensitive, since if you allocate a little more or less, the precise
location where GC happens shifts and you observe a different part of the
spike.
Andreas told me to revert the patch for now, and he will add it back
when he fixes the memory spike.
This reverts commit 41bdb16fd083110a06507248f648c507a2feb4af.
-
e10dcd65
by Sven Tennie at 2025-10-12T10:24:56+00:00
T22859: Increase threadDelay for small machines
The previously used thread delay led to failures on my RISC-V test
setups.
-
d59ef6b6
by Hai / @BestYeen at 2025-10-14T21:51:14-04:00
Change Alex and Happy m4 scripts to display which version was found in the system, adapt small formatting details in Happy script to be more like the Alex script again.
-
c98abb6a
by Hai / @BestYeen at 2025-10-14T21:52:08-04:00
Update occurrences of return to pure and add a sample for redefining :m to mean :main
-
70ee825a
by Cheng Shao at 2025-10-14T21:52:50-04:00
testsuite: fix T3586 for non-SSE3 platforms
`T3586.hs` contains `-fvia-C -optc-msse3` which I think is a
best-effort basis to harvest the C compiler's auto vectorization
optimizations via the C backend back when the test was added. The
`-fvia-C` part is now a deprecated no-op because GHC can't fall back
to the C backend on a non-unregisterised build, and `-optc-msse3`
might actually cause the test to fail on non x86/x64 platforms, e.g.
recent builds of wasi-sdk would report `wasm32-wasi-clang: error:
unsupported option '-msse3' for target 'wasm32-unknown-wasi'`.
So this patch cleans up this historical cruft. `-fvia-C` is removed,
and `-optc-msse3` is only passed when cpuid contains `pni` (which
indicates support of SSE3).
-
4be32153
by Teo Camarasu at 2025-10-15T08:06:09-04:00
Add submodules for template-haskell-lift and template-haskell-quasiquoter
These two new boot libraries expose stable subsets of the
template-haskell interface.
This is an implemenation of the GHC proposal https://github.com/ghc-proposals/ghc-proposals/pull/696
Work towards #25262
-
0c00c9c3
by Ben Gamari at 2025-10-15T08:06:51-04:00
rts: Eliminate uses of implicit constant arrays
Folding of `const`-sized variable-length arrays to a constant-length
array is a gnu extension which clang complains about.
Closes #26502.
-
bf902a1d
by Fendor at 2025-10-15T16:00:59-04:00
Refactor distinct constructor tables map construction
Adds `GHC.Types.Unique.FM.alterUFM_L`, `GHC.Types.Unique.DFM.alterUDFM_L`
`GHC.Data.Word64Map.alterLookup` to support fusion of distinct
constructor data insertion and lookup during the construction of the `DataCon`
map in `GHC.Stg.Debug.numberDataCon`.
Co-authored-by: Fendor <fendor@posteo.de>
Co-authored-by: Finley McIlwaine <finleymcilwaine@gmail.com>
-
b3585ba1
by Fendor at 2025-10-15T16:00:59-04:00
Allow per constructor refinement of distinct-constructor-tables
Introduce `-fno-distinct-constructor-tables`. A distinct constructor table
configuration is built from the combination of flags given, in order. For
example, to only generate distinct constructor tables for a few specific
constructors and no others, just pass
`-fdistinct-constructor-tables-only=C1,...,CN`.
This flag can be supplied multiple times to extend the set of
constructors to generate a distinct info table for.
You can disable generation of distinct constructor tables for all
configurations by passing `-fno-distinct-constructor-tables`.
The various configurations of these flags is included in the `DynFlags`
fingerprints, which should result in the expected recompilation logic.
Adds a test that checks for distinct tables for various given or omitted
constructors.
Updates CountDepsAst and CountDepsParser tests to account for new dependencies.
Fixes #23703
Co-authored-by: Fendor <fendor@posteo.de>
Co-authored-by: Finley McIlwaine <finleymcilwaine@gmail.com>
-
e17dc695
by fendor at 2025-10-15T16:01:41-04:00
Fix typos in haddock documentation for stack annotation API
-
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.
-
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
-
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.
-
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.
-
beae879b
by Rodrigo Mesquita at 2025-12-03T15:42:37+01:00
task: Substitute some datatypes for newtypes
* Substitutes some data type declarations for newtype declarations
* Adds comment to `LlvmConfigCache`, which must decidedly not be a
newtype.
Fixes #23555
-
3bd7dd44
by mangoiv at 2025-12-04T04:36:45-05:00
Renamer: reinstate the template haskell level check in notFound
Out-of-scope names might be caused by a staging error, as is explained by
Note [Out of scope might be a staging error] in GHC.Tc.Utils.Env.hs.
This logic was assumed to be dead code after 217caad1 and has thus been
removed. This commit reintroduces it and thus fixes issue #26099.
-
0318010b
by Zubin Duggal at 2025-12-04T04:37:27-05:00
testlib: Optionally include the way name in the expected output file
This allows us to have different outputs for different ways.
-
6d945fdd
by Zubin Duggal at 2025-12-04T04:37:27-05:00
testsuite: Accept output of tests failing in ext-interp way due to differing compilation requirements
Fixes #26552
-
0ffc5243
by Cheng Shao at 2025-12-04T04:38:09-05:00
devx: minor fixes for compile_flags.txt
This patch includes minor fixes for compile_flags.txt to improve
developer experience when using clangd as language server to hack on
RTS C sources:
- Ensure `-fPIC` is passed and `__PIC__` is defined, to be coherent
with `-DDYNAMIC` and ensure the `__PIC__` guarded code paths are
indexed
- Add the missing `-DRtsWay` definition, otherwise a few source files
like `RtsUtils.c` and `Trace.c` would produce clangd errors
-
e36a5fcb
by Matthew Pickering at 2025-12-05T16:25:57-05:00
Add support for building bytecode libraries
A bytecode library is a collection of bytecode files (.gbc) and a
library which combines together additional object files.
A bytecode library is created by invoking GHC with the `-bytecodelib`
flag.
A library can be created from in-memory `ModuleByteCode` linkables or
by passing `.gbc` files as arguments on the command line.
Fixes #26298
-
8f9ae339
by Matthew Pickering at 2025-12-05T16:25:57-05:00
Load bytecode libraries to satisfy package dependencies
This commit allows you to use a bytecode library to satisfy a package
dependency when using the interpreter.
If a user enables `-fprefer-byte-code`, then if a package provides a
bytecode library, that will be loaded and used to satisfy the
dependency.
The main change is to separate the relevant parts of the `LoaderState`
into external and home package byte code. Bytecode is loaded into either
the home package or external part (similar to HPT/EPS split), HPT
bytecode can be unloaded. External bytecode is never unloaded.
The unload function has also only been called with an empty list of
"stable linkables" for a long time. It has been modified to directly
implement a complete unloading of the home package bytecode linkables.
At the moment, the bytecode libraries are found in the "library-dirs"
field from the package description. In the future when `Cabal`
implements support for "bytecode-library-dirs" field, we can read the
bytecode libraries from there. No changes to the Cabal submodule are
necessary at the moment.
Four new tests are added in testsuite/tests/cabal, which generate fake
package descriptions and test loading the libraries into GHCi.
Fixes #26298
-
54458ce4
by mangoiv at 2025-12-05T16:26:50-05:00
ExplicitLevelImports: improve documentation of the code
- more explicit names for variable names like `flg` or `topLevel`
- don't pass the same value twice to functions
- some explanations of interesting but undocumented code paths
- adjust comment to not mention non-existent error message
-
c7061392
by mangoiv at 2025-12-05T16:27:42-05:00
driver: don't expect nodes to exist when checking paths between them
In `mgQueryZero`, previously node lookups were expected to never fail,
i.e. it was expected that when calculating the path between two nodes in
a zero level import graph, both nodes would always exist. This is not
the case, e.g. in some situations involving exact names (see the
test-case). The fix is to first check whether the node is present in the
graph at all, instead of panicking, just to report that there is no
path.
Closes #26568
-
d6cf8463
by Peng Fan at 2025-12-06T11:06:28-05:00
NCG/LA64: Simplify genCCall into two parts
genCCall is too long, so it's been simplified into two parts:
genPrim and genLibCCall.
Suggested by Andreas Klebinger
-
9d371d23
by Matthew Pickering at 2025-12-06T11:07:09-05:00
hadrian: Use a response file to invoke GHC for dep gathering.
In some cases we construct an argument list too long for GHC to
handle directly on windows. This happens when we generate
the dependency file because the command line will contain
references to a large number of .hs files.
To avoid this we now invoke GHC using a response file when
generating dependencies to sidestep length limitations.
Note that we only pass the actual file names in the dependency
file. Why? Because this side-steps #26560
-
0043bfb0
by Marc Scholten at 2025-12-06T11:08:03-05:00
update xhtml to 3000.4.0.0
haddock-api: bump xhtml bounds
haddock-api: use lazy text instead of string to support xhtml 3000.4.0.0
Bumping submodule xhtml to 3000.4.0.0
add xhtml to stage0Packages
remove unused import of writeUtf8File
Remove redundant import
Update haddock golden files for xhtml 3000.4.0.0
Metric Decrease:
haddock.Cabal
haddock.base
-
fc958fc9
by Julian Ospald at 2025-12-06T11:08:53-05:00
rts: Fix object file format detection in loadArchive
Commit 76d1041dfa4b96108cfdd22b07f2b3feb424dcbe seems to
have introduced this bug, ultimately leading to failure of
test T11788. I can only theorize that this test isn't run
in upstream's CI, because they don't build a static GHC.
The culprit is that we go through the thin archive, trying
to follow the members on the filesystem, but don't
re-identify the new object format of the member. This pins
`object_fmt` to `NotObject` from the thin archive.
Thanks to @angerman for spotting this.
-
0f297f6e
by mangoiv at 2025-12-06T11:09:44-05:00
users' guide: don't use f strings in the python script to ensure compatibility with python 3.5
-
3bfe7aa2
by Matthew Pickering at 2025-12-07T12:18:57-05:00
ci: Try using multi repl in ghc-in-ghci test
This should be quite a bit faster than the ./hadrian/ghci command as it
doesn't properly build all the dependencies.
-
2ef1601a
by Rodrigo Mesquita at 2025-12-07T12:19:38-05:00
Stack.Decode: Don't error on bitmap size 0
A RET_BCO may have a bitmap with no payload.
In that case, the bitmap = 0.
One can observe this by using -ddump-bcos and interpreting
```
main = pure ()
```
Observe, for instance, that the BCO for this main function has size 0:
```
ProtoBCO Main.main#0:
\u []
break<main:Main,0>() GHC.Internal.Base.pure
GHC.Internal.Base.$fApplicativeIO GHC.Internal.Tuple.()
bitmap: 0 []
BRK_FUN <breakarray> main:Main 0 <cc>
PACK () 0
PUSH_G GHC.Internal.Base.$fApplicativeIO
PUSH_APPLY_PP
PUSH_G GHC.Internal.Base.pure
ENTER
```
Perhaps we never tried to decode a stack in which a BCO like this was
present. However, for the debugger, we want to decode stacks of threads
stopped at breakpoints, and these kind of BCOs do get on a stack under
e.g. `stg_apply_interp_info` frames.
See the accompanying test in the next commit for an example to trigger
the bug this commit fixes.
Fixes #26640
-
747153d2
by Rodrigo Mesquita at 2025-12-07T12:19:38-05:00
Add test for #26640
-
d4b1e353
by Simon Hengel at 2025-12-10T00:00:02-05:00
Fix syntax error in gadt_syntax.rst
-
91cc8be6
by Cheng Shao at 2025-12-10T00:00:43-05:00
ci: fix "ci.sh clean" to address frequent out of space error on windows runners
This patch fixes the `ci.sh clean` logic to address frequent out of
space error on windows runners; previously it didn't clean up the
inplace mingw blobs, which is the largest source of space leak on
windows runners. See added comment for detailed explanation.
-
fe2b79f4
by Recursion Ninja at 2025-12-10T08:34:18-05:00
Narrow before optimising MUL/DIV/REM into shifts
The MUL/DIV/REM operations can be optimised into shifts when one of the
operands is a constant power of 2. However, as literals in Cmm are
stored as 'Integer', for this to be correct we first need to narrow the
literal to the appropriate width before checking whether the literal is
a power of 2.
Fixes #25664
-
06c2349c
by Recursion Ninja at 2025-12-10T08:34:58-05:00
Decouple 'Language.Haskell.Syntax.Type' from 'GHC.Utils.Panic'
- Remove the *original* defintion of 'hsQTvExplicit' defined within 'Language.Haskell.Syntax.Type'
- Redefine 'hsQTvExplicit' as 'hsq_explicit' specialized to 'GhcPass' exported by 'GHC.Utils.Panic'
- Define 'hsQTvExplicitBinders' as 'hsq_explicit' specialized to 'DocNameI' exported by 'Haddock.GhcUtils'.
- Replace all call sites of the original 'hsQTvExplicit' definition with either:
1. 'hsQTvExplicit' updated definition
2. 'hsQTvExplicitBinders'
All call sites never entered the 'XLHsQTyVars' constructor branch, but a call to 'panic' existed on this code path because the type system was not strong enought to guarantee that the 'XLHsQTyVars' construction was impossible.
These two specialized functions provide the type system with enough information to make that guarantee, and hence the dependancy on 'panic' can be removed.
-
ac0815d5
by sheaf at 2025-12-10T23:39:57-05:00
Quantify arg before mult in function arrows
As noted in #23764, we expect quantification order to be left-to-right,
so that in a type such as
a %m -> b
the inferred quantification order should be [a, m, b] and not [m, a, b].
This was addressed in commit d31fbf6c, but that commit failed to update
some other functions such as GHC.Core.TyCo.FVs.tyCoFVsOfType.
This affects Haddock, as whether we print an explicit forall or not
depends on whether the inferred quantification order matches the actual
quantification order.
-
2caf796e
by sheaf at 2025-12-10T23:39:57-05:00
Haddock: improvements to ty-var quantification
This commit makes several improvements to how Haddock deals with the
quantification of type variables:
1. In pattern synonyms, Haddock used to jumble up universal and
existential quantification. That is now fixed, fixing #26252.
Tested in the 'PatternSyns2' haddock-html test.
2. The logic for computing whether to use an explicit kind annotation
for a type variable quantified in a forall was not even wrong.
This commit improves the heuristic, but it will always remain an
imperfect heuristic (lest we actually run kind inference again).
In the future (#26271), we hope to avoid reliance on this heuristic.
-
b14bdd59
by Teo Camarasu at 2025-12-10T23:40:38-05:00
Add explicit export list to GHC.Num
Let's make clear what this module exports to allow us to easily deprecate and remove some of these in the future. Resolves https://gitlab.haskell.org/ghc/ghc/-/issues/26625
-
d99f8326
by Cheng Shao at 2025-12-11T19:14:18-05:00
compiler: remove unused CPP code in foreign stub
This patch removes unused CPP code in the generated foreign stub:
- `#define IN_STG_CODE 0` is not needed, since `Rts.h` already
includes this definition
- The `if defined(__cplusplus)` code paths are not needed in the `.c`
file, since we don't generate C++ stubs and don't include C++
headers in our stubs. But it still needs to be present in the `.h`
header since it might be later included into C++ source files.
-
46c9746f
by Cheng Shao at 2025-12-11T19:14:57-05:00
configure: bump LlvmMaxVersion to 22
This commit bumps LlvmMaxVersion to 22; 21.x releases have been
available since Aug 26th, 2025 and there's no regressions with 21.x so
far. This bump is also required for updating fedora image to 43.
-
96fce8d0
by Cheng Shao at 2025-12-12T01:17:51+01:00
hadrian: add support for building with UndefinedBehaviorSanitizer
This patch adds a +ubsan flavour transformer to hadrian to build all
stage1+ C/C++ code with UndefinedBehaviorSanitizer. This is
particularly useful to catch potential undefined behavior in the RTS
codebase.
-
f7a06d8c
by Cheng Shao at 2025-12-12T01:17:51+01:00
ci: update alpine/fedora & add ubsan job
This patch updates alpine image to 3.23, fedora image to 43, and adds
a `x86_64-linux-fedora43-validate+debug_info+ubsan` job that's run in
validate/nightly pipelines to catch undefined behavior in the RTS
codebase.
-
2ccd11ca
by Cheng Shao at 2025-12-12T01:17:51+01:00
rts: fix zero-length VLA undefined behavior in interpretBCO
This commit fixes a zero-length VLA undefined behavior in interpretBCO, caught by UBSan:
```
+rts/Interpreter.c:3133:19: runtime variable length array bound evaluates to non-positive value 0
```
-
4156ed19
by Cheng Shao at 2025-12-12T01:17:51+01:00
rts: fix unaligned ReadSpB in interpretBCO
This commit fixes unaligned ReadSpB in interpretBCO, caught by UBSan:
```
+rts/Interpreter.c:2174:64: runtime load of misaligned address 0x004202059dd1 for type 'StgWord', which requires 8 byte alignment
```
To perform proper unaligned read, we define StgUnalignedWord as a type
alias of StgWord with aligned(1) attribute, and load StgUnalignedWord
instead of StgWord in ReadSpB, so the C compiler is aware that we're
not loading with natural alignment.
-
fef89fb9
by Cheng Shao at 2025-12-12T01:17:51+01:00
rts: fix signed integer overflow in subword arithmetic in interpretBCO
This commit fixes signed integer overflow in subword arithmetic in
interpretBCO, see added note for detailed explanation.
-
3c001377
by Cheng Shao at 2025-12-13T05:03:15-05:00
ci: use treeless fetch for perf notes
This patch improves the ci logic for fetching perf notes by using
treeless fetch
(https://github.blog/open-source/git/get-up-to-speed-with-partial-clone-and-shallow-clone),
to avoid downloading all blobs of the perf notes repo at once, and
only fetch the actually required blobs on-demand when needed. This
makes the initial `test-metrics.sh pull` operation much faster, and
also more robust, since we are seeing an increasing rate of 504 errors
in CI when fetching all perf notes at once, which is a major source of
CI flakiness at this point.
Co-authored-by: Codex <codex@openai.com>
-
123a8d77
by Peter Trommler at 2025-12-13T05:03:57-05:00
Cmm: remove restriction in MachOp folding
-
0b54b5fd
by Andreas Klebinger at 2025-12-13T05:04:38-05:00
Remove explicit Typeable deriviations.
-
08b13f7b
by Cheng Shao at 2025-12-13T05:05:18-05:00
ci: set gc.auto=0 during setup stage
This patch sets `gc.auto=0` during `setup` stage of CI, see added
comment for detailed explanation.
-
3b5aecb5
by Ben Gamari at 2025-12-13T23:43:10+01:00
Bump exceptions submodule to 0.10.11
-
c32de3b0
by Johan Förberg at 2025-12-15T02:36:03-05:00
base: Define Semigroup and Monoid instances for lazy ST
CLC proposal:
https://github.com/haskell/core-libraries-committee/issues/374
Fixes #26581
-
4f8b660c
by mangoiv at 2025-12-15T02:37:05-05:00
ci: do not require nightly cabal-reinstall job to succeed
-
2c2a3ef3
by Cheng Shao at 2025-12-15T11:51:53-05:00
docs: drop obsolete warning about -fexternal-interpreter on windows
This patch drops an obsolete warning about -fexternal-interpreter not
supported on windows; it is supported since a long time ago, including
the profiled way.
-
68573aa5
by Marc Scholten at 2025-12-15T11:53:00-05:00
haddock: Drop Haddock.Backends.HaddockDB as it's unused
-
b230d549
by mangoiv at 2025-12-16T15:17:45-05:00
base: generalize delete{Firsts,}By
When we delete{Firsts,}By we should not require the
lists to be the same type. This is an especially useful
generalisation in the case of deleteFirstsBy because we
can skip an invocation of the map function.
This change was discussed on the core-libraries-committee's bug
tracker at https://github.com/haskell/core-libraries-committee/issues/372.
-
6a2b43e3
by Cheng Shao at 2025-12-16T15:18:30-05:00
compiler: clean up redundant LANGUAGE pragmas
This patch bumps `default-language` of `ghc`/`ghc-bin` from `GHC2021`
to `GHC2024` (which is supported in ghc 9.10, current boot ghc lower
version bound), and also cleans up redundant `LANGUAGE` pragmas (as
well as `default-extensions`/`other-extensions`) that are already
implied by `GHC2024`.
Co-authored-by: Codex <codex@openai.com>
-
fca9cd7c
by sheaf at 2025-12-18T13:18:18-05:00
X86 CodeGen: fix assign_eax_sse_regs
We must set %al to the number of SSE2 registers that contain arguments
(in case we are dealing with a varargs function). The logic for counting
how many arguments reside in SSE2 registers was incorrect, as it used
'isFloatFormat', which incorrectly ignores vector registers.
We now instead do case analysis on the register class:
is_sse_reg r =
case targetClassOfReg platform r of
RcFloatOrVector -> True
RcInteger -> False
This change is necessary to prevent segfaults in T20030_test1j, because
subsequent commits change the format calculations, resulting in vector
formats more often.
-
53150617
by sheaf at 2025-12-18T13:18:19-05:00
X86 regUsageOfInstr: fix format for IMUL
When used with 8-bit operands, the IMUL instruction returns the result
in the lower 16 bits of %rax (also known as %ax). This is different
than for the other sizes, where an input at 16, 32 or 64 bits will
result in 16, 32 or 64 bits of output in both %rax and %rdx.
This doesn't affect the behaviour of the compiler, because we don't
allow partial writes at sub-word sizes. The rationale is explained
in Wrinkle [Don't allow scalar partial writes] in Note [Register formats in liveness analysis],
in GHC.CmmToAsm.Reg.Liveness.
-
c7a56dd1
by sheaf at 2025-12-18T13:18:19-05:00
Liveness analysis: consider register formats
This commit updates the register allocator to be a bit more careful in
situations in which a single register is used at multiple different
formats, e.g. when xmm1 is used both to store a Double# and a DoubleX2#.
This is done by introducing the 'Regs' newtype around 'UniqSet RegWithFormat',
for which the combining operations take the larger of the two formats
instead of overriding the format.
Operations on 'Regs' are defined in 'GHC.CmmToAsm.Reg.Regs'. There is
a modest compile-time cost for the additional overhead for tracking
register formats, which causes the metric increases of this commit.
The subtle aspects of the implementation are outlined in
Note [Register formats in liveness analysis] in GHC.CmmToAsm.Reg.Liveness.
Fixes #26411 #26611
-------------------------
Metric Increase:
T12707
T26425
T3294
-------------------------
-
c2e83339
by sheaf at 2025-12-18T13:18:19-05:00
Register allocator: reload at same format as spill
This commit ensures that if we spill a register onto the stack at a
given format, we then always reload the register at this same format.
This ensures we don't end up in a situation where we spill F64x2 but end
up only reloading the lower F64. This first reload would make us believe
the whole data is in a register, thus silently losing the upper 64 bits
of the spilled register's contents.
Fixes #26526
-
55ab583b
by sheaf at 2025-12-18T13:18:19-05:00
Register allocation: writes redefine format
As explained in Note [Allocated register formats] in GHC.CmmToAsm.Reg.Linear,
we consider all writes to redefine the format of the register.
This ensures that in a situation such as
movsd .Ln6m(%rip),%v1
shufpd $0,%v1,%v1
we properly consider the broadcast operation to change the format of %v1
from F64 to F64x2.
This completes the fix to #26411 (test in T26411b).
-
951402ed
by Vladislav Zavialov at 2025-12-18T13:19:05-05:00
Parser: improve mkModuleImpExp, remove checkImportSpec
1. The `mkModuleImpExp` helper now knows whether it is processing an import or
export list item, and uses this information to produce a more accurate error
message for `import M (T(..,x))` with PatternSynonyms disabled.
The old message incorrectly referred to this case as an export form.
2. The `checkImportSpec` helper is removed in favor of more comprehensive error
checking in `mkModuleImpExp`.
3. Additionaly, the invariants of `ImpExpList` and `ImpExpAllWith` have been
made more explicit in the comments and assertions (calls to 'panic').
Test case: import-syntax-no-ext
-
47d83d96
by Vladislav Zavialov at 2025-12-18T13:19:06-05:00
Subordinate namespace-specified wildcards (#25901)
Add support for subordinate namespace-specified wildcards
`X(type ..)` and `X(data ..)` to import and export lists.
Examples:
import M (Cls(type ..)) -- imports Cls and all its associated types
import M (Cls(data ..)) -- imports Cls and all its methods
module M (R(data ..), C(type ..)) where
-- exports R and all its data constructors and record fields;
-- exports C and all its associated types, but not its methods
The scope of this change is limited to the case where the wildcard is the only
subordinate import/export item, whereas the more complex forms `X(type .., f)`
or `X(type .., data ..)` are unsupported and raise the newly introduced
PsErrUnsupportedExplicitNamespace error. This restriction may be lifted later.
Summary of the changes:
1. Refactor IEThingAll to store its extension field XIEThingAll as a record
IEThingAllExt instead of a tuple.
2. Extend the AST by adding a NamespaceSpecifier field to IEThingAllExt,
representing an optional namespace specifier `type` or `data` in front
of a subordinate wildcard `X(..)`.
3. Extend the grammar in Parser.y with productions for `type ..` and `data ..`
in subordinate import/export items.
4. Introduce `filterByNamespaceGREs` to filter [GlobalRdrElt] by a
NamespaceSpecifier; use it in `filterImports` and `exports_from_avail`
to account for the namespace specifier in IEThingAll.
5. Improve diagnostics by storing more information in DodgyImportsEmptyParent
and DodgyExportsEmptyParent.
Test cases:
T25901_sub_e T25901_sub_f T25901_sub_g T25901_sub_a
T25901_sub_b T25901_sub_c T25901_sub_d T25901_sub_w
DodgyImports02 DodgyImports03 DodgyImports04
-
eac418bb
by Recursion Ninja at 2025-12-18T13:19:48-05:00
Removing the 'Data' instance for 'InstEnv'.
The 'Data' instance is blocking work on Trees that Grow, and the
'Data' instance seem to have been added without a clear purpose.
-
e920e038
by Recursion Ninja at 2025-12-18T13:19:48-05:00
'Decouple Language.Haskell.Syntax.Decls' from 'GHC.Unit.Module.Warnings'
-
bd38b76c
by Cheng Shao at 2025-12-18T13:20:31-05:00
testsuite: improve coverage of foundation test
This patch refactors the `foundation` test a bit to improve coverage:
- Instead of using a hard-coded seed, a random seed is now taken from
the command line, and printed upon test failure. This improves test
coverage over many future CI runs, and shall a failure occur, the
seed is available in the CI log for local reproduction.
- The iterations count is bumped to 1000 instead of 100, similar to
the bump in `test-primops`. Runtime timeout is bumped 2x just to be
safe.
- Improve `newLCGGen` by using non-atomic loads/stores on a
`MutableByteArray#` for storing mutable `Word64`, this test doesn't
use parallelism in the first place
- Fixed a few compiler warnings and removed redundant pragmas and
imports
Co-authored-by: Codex <codex@openai.com>
-
3995187c
by Sylvain Henry at 2025-12-18T13:21:45-05:00
Doc: document -pgmi "" (#26634)
-
5729418c
by Cheng Shao at 2025-12-18T13:22:29-05:00
rts: use __builtin_mul_overflow for hs_mulIntMayOflo
This patch uses `__builtin_mul_overflow` to implement
`hs_mulIntMayOflo`. This is a GNU C checked arithmetic builtin
function supported by gcc/clang, is type-generic so works for both
32-bit/64-bit, and makes the code both more efficient and easier to
read/maintain than the previous hand rolled logic.
-
1ca4b49a
by Cheng Shao at 2025-12-18T13:23:11-05:00
compiler/rts: fix ABI mismatch in barf() invocations
This patch fixes a long-standing issue of ABI mismatch in `barf()`
invocations, both in compiler-emitted code and in hand written Cmm
code:
- In RTS, we have `barf()` which reports a fatal internal error
message and exits the program.
- `barf()` is a variadic C function! When used as a callee of a
foreign call with `ccall` calling convention instead of `capi`,
there is an ABI mismatch between the caller and the callee!
- Unfortunately, both the compiler and the Cmm sources contain many
places where we call `barf()` via `ccall` convention!! Like, when
you write `foreign "C" barf("foo object (%p) entered!", R1)`, it
totally doesn't do what you think it'll do at all!! The second
argument `R1` is not properly passed in `va_list`, and the behavior
is completely undefined!!
- Even more unfortunately, this issue has been sitting around long
enough because the ABI mismatch is subtle enough on normie platforms
like x64 and arm64.
- But there are platforms like wasm32 that are stricter about ABI, and
the broken `barf()` invocations already causes trouble for wasm
backend: we had to use ugly hacks like `barf(errmsg, NULL)` to make
`wasm-ld` happy, and even with this band-aid, compiler-generated
`barf()` invocations are still broken, resulting in regressions in
certain debug-related functionality, e.g. `-dtag-inference-checks`
is broken on wasm32 (#22882).
This patch properly fixes the issue:
- We add non-variadic `barf` wrappers in the RTS that can be used as
`ccall` callees
- Both the compiler `emitBarf` logic and the hand-written Cmm are
changed to call these wrappers
- `emitBarf` now also properly annotates the foreign call as
`CmmNeverReturns` to indicate it's a noreturn call to enable more
efficient code generation
`-dtag-inference-checks` now works on wasm. Closes #22882.
Co-authored-by: Codex <codex@openai.com>
-
b3dd23b9
by Vilim Lendvaj at 2025-12-18T13:23:57-05:00
Remove outdated comment
The Traversable instance for ZipList is no longer in
GHC.Internal.Data.Traversable. In fact, it is right below this very comment.
-
9a9c2f03
by Cheng Shao at 2025-12-18T13:24:39-05:00
compiler: remove unused OtherSection logic
This patch removes the OtherSection logic in Cmm, given it's never
actually used by any of our backends.
-
91edd292
by Wolfgang Jeltsch at 2025-12-19T03:18:19-05:00
Remove unused known-key and name variables for generics
This removes the known-key and corresponding name variables for `K1`,
`M1`, `R`, `D`, `C`, `S`, and `URec` from `GHC.Generics`, as they are
apparently nowhere used in GHC’s source code.
-
73ee7e38
by Wolfgang Jeltsch at 2025-12-19T03:19:02-05:00
Remove unused known keys and names for generics classes
This removes the known-key and corresponding name variables for
`Datatype`, `Constructor`, and `Selector` from `GHC.Generics`, as they
are apparently nowhere used in GHC’s source code.
-
f69c5f14
by Cheng Shao at 2025-12-19T03:19:45-05:00
wasm: fix handling of ByteArray#/MutableByteArray# arguments in JSFFI imports
This patch fixes the handling of ByteArray#/MutableByteArray#
arguments in JSFFI imports, see the amended note and manual for
explanation. Also adds a test to witness the fix.
Co-authored-by: Codex <codex@openai.com>
-
224446a2
by Cheng Shao at 2025-12-20T07:49:54-05:00
rts: workaround -Werror=maybe-uninitialized false positives
In some cases gcc might report -Werror=maybe-uninitialized that we
know are false positives, but need to workaround it to make validate
builds with -Werror pass.
-
251ec087
by Cheng Shao at 2025-12-20T07:49:54-05:00
hadrian: use -Og as C/C++ optimization level when debugging
This commit enables -Og as optimization level when compiling the debug
ways of rts. According to gcc documentation
(https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html#index-Og),
-Og is a better choice than -O0 for producing debuggable code. It's
also supported by clang as well, so it makes sense to use it as a
default for debugging. Also add missing -g3 flag to C++ compilation
flags in +debug_info flavour transformer.
-
fb586c67
by Cheng Shao at 2025-12-20T07:50:36-05:00
compiler: replace DList with OrdList
This patch removes `DList` logic from the compiler and replaces it
with `OrdList` which also supports O(1) concatenation and should be
more memory efficient than the church-encoded `DList`.
-
8149c987
by Cheng Shao at 2025-12-20T17:06:51-05:00
hadrian: add with_profiled_libs flavour transformer
This patch adds a `with_profiled_libs` flavour transformer to hadrian
which is the exact opposite of `no_profiled_libs`. It adds profiling
ways to stage1+ rts/library ways, and doesn't alter other flavour
settings. It is useful when needing to test profiling logic locally
with a quick flavour.
-
746b18cd
by Cheng Shao at 2025-12-20T17:06:51-05:00
hadrian: fix missing profiled dynamic libraries in profiled_ghc
This commit fixes the profiled_ghc flavour transformer to include
profiled dynamic libraries as well, since they're supported by GHC
since !12595.
-
4dd7e3b9
by Cheng Shao at 2025-12-20T17:07:33-05:00
ci: set http.postBuffer to mitigate perf notes timeout on some runners
This patch sets http.postBuffer to mitigate the timeout when fetching
perf notes on some runners with slow internet connection. Fixes #26684.
-
bc36268a
by Wolfgang Jeltsch at 2025-12-21T16:23:24-05:00
Remove unused known keys and names for type representations
This removes the known-key and corresponding name variables for
`TrName`, `TrNameD`, `TypeRep`, `KindRepTypeLitD`, `TypeLitSort`, and
`mkTrType`, as they are apparently nowhere used in GHC’s source code.
-
ff5050e9
by Wolfgang Jeltsch at 2025-12-21T16:24:04-05:00
Remove unused known keys and names for natural operations
This removes the known-key and corresponding name variables for
`naturalAndNot`, `naturalLog2`, `naturalLogBaseWord`, `naturalLogBase`,
`naturalPowMod`, `naturalSizeInBase`, `naturalToFloat`, and
`naturalToDouble`, as they are apparently nowhere used in GHC’s source
code.
-
424388c2
by Wolfgang Jeltsch at 2025-12-21T16:24:45-05:00
Remove the unused known key and name for `Fingerprint`
This removes the variables for the known key and the name of the
`Fingerprint` data constructor, as they are apparently nowhere used in
GHC’s source code.
-
a1ed86fe
by Wolfgang Jeltsch at 2025-12-21T16:25:26-05:00
Remove the unused known key and name for `failIO`
This removes the variables for the known key and the name of the
`failIO` operation, as they are apparently nowhere used in GHC’s source
code.
-
b8220daf
by Wolfgang Jeltsch at 2025-12-21T16:26:07-05:00
Remove the unused known key and name for `liftM`
This removes the variables for the known key and the name of the `liftM`
operation, as they are apparently nowhere used in GHC’s source code.
-
eb0628b1
by Wolfgang Jeltsch at 2025-12-21T16:26:47-05:00
Fix the documentation of `hIsClosed`
-
db1ce858
by sheaf at 2025-12-22T17:11:17-05:00
Do deep subsumption when computing valid hole fits
This commit makes a couple of improvements to the code that
computes "valid hole fits":
1. It uses deep subsumption for data constructors.
This matches up the multiplicities, as per
Note [Typechecking data constructors].
This fixes #26338 (test: LinearHoleFits).
2. It now suggests (non-unidirectional) pattern synonyms as valid
hole fits. This fixes #26339 (test: PatSynHoleFit).
3. It uses 'stableNameCmp', to make the hole fit output deterministic.
-------------------------
Metric Increase:
hard_hole_fits
-------------------------
-
72ee9100
by sheaf at 2025-12-22T17:11:17-05:00
Speed up hole fits with a quick pre-test
This speeds up the machinery for valid hole fits by doing a small
check to rule out obviously wrong hole fits, such as:
1. A hole fit identifier whose type has a different TyCon at the head,
after looking through foralls and (=>) arrows, e.g.:
hole_ty = Int
cand_ty = Maybe a
or
hole_ty = forall a b. a -> b
cand_ty = forall x y. Either x y
2. A hole fit identifier that is not polymorphic when the hole type
is polymorphic, e.g.
hole_ty = forall a. a -> a
cand_ty = Int -> Int
-------------------------
Metric Decrease:
hard_hole_fits
-------------------------
-
30e513ba
by Cheng Shao at 2025-12-22T17:12:00-05:00
configure: remove unused win32-tarballs.md5sum
This patch removes the unused `win32-tarballs.md5sum` file from the
tree. The current mingw tarball download logic in
`mk/get-win32-tarballs.py` fetches and checks against `SHA256SUM` from
the same location where the tarballs are fetched, and this file has
been unused for a few years.
-
a2d52b3b
by Wolfgang Jeltsch at 2025-12-23T04:47:33-05:00
Add an operation `System.IO.hGetNewlineMode`
This commit also contains some small code and documentation changes for
related operations, for the sake of consistency.
-
b26d134a
by Cheng Shao at 2025-12-23T04:48:15-05:00
rts: opportunistically reclaim slop space in shrinkMutableByteArray#
Previously, `shrinkMutableByteArray#` shrinks a `MutableByteArray#`
in-place by assigning the new size to it, and zeroing the extra slop
space. That slop space is not reclaimed and wasted. But it's often the
case that we allocate a `MutableByteArray#` upfront, then shrink it
shortly after, so the `MutableByteArray#` closure sits right at the
end of a nursery block; this patch identifies such chances, and also
shrink `bd->free` if possible, reducing heap space fragmentation.
Co-authored-by: Codex <codex@openai.com>
-------------------------
Metric Decrease:
T10678
-------------------------
-
c72ddabf
by Cheng Shao at 2025-12-23T16:13:23-05:00
hadrian: fix bootstrapping with ghc-9.14
This patch fixes bootstrapping GHC with ghc-9.14, tested locally with
ghc-9.14.1 release as bootstrapping GHC.
-
0fd6d8e4
by Cheng Shao at 2025-12-23T16:14:05-05:00
hadrian: pass -keep-tmp-files to test ghc when --keep-test-files is enabled
This patch makes hadrian pass `-keep-tmp-files` to test ghc when
`--keep-test-files` is enabled, so you can check the ghc intermediate
files when debugging certain test failures. Closes #26688.
-
81d10134
by Cheng Shao at 2025-12-24T06:11:52-05:00
configure: remove dead code in configure scripts
This patch removes dead code in our configure scripts, including:
- Variables and auto-detected programs that are not used
- autoconf functions that are not used, or export a variable that's
not used
- `AC_CHECK_HEADERS` invocations that don't have actual corresponding
`HAVE_XXX_H` usage
- Other dead code (e.g. stray `AC_DEFUN()`)
Co-authored-by: Codex <codex@openai.com>
-
fb1381c3
by Wolfgang Jeltsch at 2025-12-24T06:12:34-05:00
Remove unused known keys and names for list operations
This removes the known-key and corresponding name variables for
`concat`, `filter`, `zip`, and `(++)`, as they are apparently nowhere
used in GHC’s source code.
-
7b9c20f4
by Recursion Ninja at 2025-12-24T10:35:36-05:00
Decoupling Language.Haskell.Syntax.Binds from GHC.Types.Basic
by transferring InlinePragma types between the modules.
* Moved InlinePragma data-types to Language.Haskell.Syntax.Binds.InlinePragma
* Partitioned of Arity type synonyms to GHC.Types.Arity
* InlinePragma is now extensible via Trees That Grow
* Activation is now extensible via Trees That Grow
* Maybe Arity change to more descriptive InlineSaturation data-type
* InlineSaturation information removed from InlinePragma during GHS parsing pass
* Cleaned up the exposed module interfaces of the new modules
-
a3afae0c
by Simon Peyton Jones at 2025-12-25T15:26:36-05:00
Check for rubbish literals in Lint
Addresses #26607.
See new Note [Checking for rubbish literals] in GHC.Core.Lint
-
8a317b6f
by Aaron Allen at 2026-01-01T03:05:15-05:00
[#26183] Associated Type Iface Fix
When determining "extras" for class decl interface entries, axioms for
the associated types need to included so that dependent modules will be
recompiled if those axioms change.
resolves #26183
-
ae1aeaab
by Cheng Shao at 2026-01-01T03:06:32-05:00
testsuite: run numeric tests with optasm when available
This patch adds the `optasm` extra way to nueric tests when NCG is
available. Some numeric bugs only surface with optimization, omitting
this can hide these bugs and even make them slip into release! (e.g. #26711)
-
6213bb57
by maralorn at 2026-01-02T16:30:32+01:00
GHC.Internal.Exception.Context: Fix comment
on addExceptionAnnotation
-
b820ff50
by Janis Voigtlaender at 2026-01-05T02:43:18-05:00
GHC.Internal.Control.Monad.replicateM: Fix comment
-
a8a94aad
by Cheng Shao at 2026-01-05T16:24:04-05:00
hadrian: drops unused PE linker script for windows
This patch drops unused PE linker script for windows in the
`MergeObjects` builder of hadrian. The linker script is used for
merging object files into a single `HS*.o` object file and undoing the
effect of split sections, when building the "ghci library" object
file. However, we don't build the ghci library on windows, and this
code path is actually unreachable.
-
53038ea9
by Cheng Shao at 2026-01-05T16:24:04-05:00
hadrian: drop unused logic for building ghci libraries
This patch drops the unused logic for building ghci libraries in
hadrian:
- The term "ghci library" refers to an optional object file per
library `HS*.o`, which is merged from multiple object files in that
library using the `MergeObjects` builder in hadrian.
- The original rationale of having a ghci library object, in addition
to normal archives, was to speedup ghci loading, since the combined
object is linked with a linker script to undo the effects of
`-fsplit-sections` to reduce section count and make it easier for
the RTS linker to handle.
- However, most GHC builds enable `dynamicGhcPrograms` by default, in
such cases the ghci library would already not be built.
- `dynamicGhcPrograms` is disabled on Windows, but still we don't
build the ghci library due to lack of functioning merge objects
command.
- The only case that we actually build ghci library objects, are
alpine fully static bindists. However, for other reasons, split
sections is already disabled for fully static builds anyway!
- There will not be any regression if the ghci library objects are
absent from a GHC global libdir when `dynamicGhcPrograms` is
disabled. The RTS linker can already load the archives without any
issue.
Hence the removal. We now forcibly disable ghci libraries for all
Cabal components, and rip out all logic related to `MergeObjects` and
ghci libraries in hadrian. This also nicely cleans up some old todos
and fixmes that are no longer relevant.
Note that MergeObjects in hadrian is not the same thing as merge
objects in the GHC driver. The latter is not affected by this patch.
-------------------------
Metric Decrease:
libdir
-------------------------
Co-authored-by: Codex <codex@openai.com>
-
8f209336
by Simon Jakobi at 2026-01-05T16:24:48-05:00
User's guide: Fix link to language extensions
Instead of linking to haddocks, it seemed more useful to link
to the extension overview in the user's guide.
Closes #26614.
-
0b7df6db
by Simon Peyton Jones at 2026-01-06T09:32:23-05:00
Improved fundeps for closed type families
The big payload of this commit is to execute the plan suggested
in #23162, by improving the way that we generate functional
dependencies for closed type families.
It is all described in Note [Exploiting closed type families]
Most of the changes are in GHC.Tc.Solver.FunDeps
Other small changes
* GHC.Tc.Solver.bumpReductionDepth. This function brings together the code that
* Bumps the depth
* Checks for overflow
Previously the two were separated, sometimes quite widely.
* GHC.Core.Unify.niFixSubst: minor improvement, removing an unnecessary
itraetion in the base case.
* GHC.Core.Unify: no need to pass an InScopeSet to
tcUnifyTysForInjectivity. It can calculate one for itself; and it is
never inspected anyway so it's free to do so.
* GHC.Tc.Errors.Ppr: slight impovement to the error message for
reduction-stack overflow, when a constraint (rather than a type) is
involved.
* GHC.Tc.Solver.Monad.wrapUnifier: small change to the API
-
fde8bd88
by Simon Peyton Jones at 2026-01-06T09:32:23-05:00
Add missing (KK4) to kick-out criteria
There was a missing case in kick-out that meant we could fail
to solve an eminently-solvable constraint.
See the new notes about (KK4)
-
00082844
by Simon Peyton Jones at 2026-01-06T09:32:23-05:00
Some small refactorings of error reporting in the typechecker
This is just a tidy-up commit.
* Add ei_insoluble to ErrorItem, to cache insolubility.
Small tidy-up.
* Remove `is_ip` and `mkIPErr` from GHC.Tc.Errors; instead enhance mkDictErr
to handle implicit parameters. Small refactor.
-
fe4cb252
by Simon Peyton Jones at 2026-01-06T09:32:24-05:00
Improve recording of insolubility for fundeps
This commit addresses #22652, by recording when the fundeps for
a constraint are definitely insoluble. That in turn improves the
perspicacity of the pattern-match overlap checker.
See Note [Insoluble fundeps]
-
df0ffaa5
by Simon Peyton Jones at 2026-01-06T09:32:24-05:00
Fix a buglet in niFixSubst
The MR of which this is part failed an assertion check extendTvSubst
because we extended the TvSubst with a CoVar. Boo.
This tiny patch fixes it, and adds the regression test from #13882
that showed it up.
-
3d6aba77
by konsumlamm at 2026-01-06T09:33:16-05:00
Fix changelog formatting
-
69e0ab59
by Cheng Shao at 2026-01-06T19:37:56-05:00
compiler: add targetHasRTSWays function
This commit adds a `targetHasRTSWays` util function in
`GHC.Driver.Session` to query if the target RTS has a given Ways (e.g.
WayThreaded).
-
25a0ab94
by Cheng Shao at 2026-01-06T19:37:56-05:00
compiler: link on-demand external interpreter with threaded RTS
This commit makes the compiler link the on-demand external interpreter
program with threaded RTS if it is available in the target RTS ways.
This is a better default than the previous single-threaded RTS, and it
enables the external interpreter to benefit from parallelism when
deserializing CreateBCOs messages.
-
92404a2b
by Cheng Shao at 2026-01-06T19:37:56-05:00
hadrian: link iserv with threaded RTS
This commit makes hadrian link iserv with threaded RTS if it's
available in the RTS ways. Also cleans up the iserv main C program
which can be replaced by the `-fkeep-cafs` link-time option.
-
a20542d2
by Cheng Shao at 2026-01-06T19:38:38-05:00
ghc-internal: remove unused GMP macros
This patch removes unused GMP related macros from `ghc-internal`. The
in-tree GMP version was hard coded and outdated, but it was not used
anywhere anyway.
-
4079dcd6
by Cheng Shao at 2026-01-06T19:38:38-05:00
hadrian: fix in-tree gmp configure error on newer c compilers
Building in-tree gmp on newer c compilers that default to c23 fails at
configure stage, this patch fixes it, see added comment for
explanation.
-
414d1fe1
by Cheng Shao at 2026-01-06T19:39:20-05:00
compiler: fix LLVM backend pdep/pext handling for i386 target
This patch fixes LLVM backend's pdep/pext handling for i386 target,
and also removes non-existent 128/256/512 bit hs_pdep/hs_pext callees.
See amended note for more explanation. Fixes #26450.
Co-authored-by: Codex <codex@openai.com>
-
c7f6fba3
by Cheng Shao at 2026-01-06T19:39:20-05:00
ci: remove allow_failure flag for i386 alpine job
The LLVM codegen issue for i386 has been fixed, and the i386 alpine
job should pass now. This commit removes the allow_failure flag so
that other i386 regressions in the future are signaled more timely.
-
52d00c05
by Simon Peyton Jones at 2026-01-07T10:24:21-05:00
Add missing InVar->OutVar lookup in SetLevels
As #26681 showed, the SetLevels pass was failing to map an InVar to
an OutVar. Very silly! I'm amazed it hasn't broken before now.
I have improved the type singatures (to mention InVar and OutVar)
so it's more obvious what needs to happen.
-
ab0a5594
by Cheng Shao at 2026-01-07T10:25:04-05:00
hadrian: drop deprecated pkgHashSplitObjs code path
This patch drops deprecated `pkgHashSplitObjs` code path from hadrian,
since GHC itself has removed split objs support many versions ago and
this code path is unused.
-
bb3a2ba1
by Cheng Shao at 2026-01-07T10:25:44-05:00
hadrian: remove linting/assertion in quick-validate flavour
The `quick-validate` flavour is meant for testing ghc and passing the
testsuite locally with similar settings to `validate` but faster. This
patch removes the linting/assertion overhead in `quick-validate` to
improve developer experience. I also took the chance to simplify
redundant logic of rts/library way definition in `validate` flavour.
-
7971f5dd
by Cheng Shao at 2026-01-07T10:26:26-05:00
deriveConstants: clean up unused constants
This patch cleans up unused constants from `deriveConstants`, they are
not used by C/Cmm code in the RTS, nor compiler-generated code.
Co-authored-by: Codex <codex@openai.com>
-
4df96993
by Cheng Shao at 2026-01-07T10:27:08-05:00
hadrian: pass -fno-omit-frame-pointer with +debug_info
This patch adds `-fno-omit-frame-pointer` as C/C++ compilation flag
when compiling with `+debug_info` flavour transformer. It's a sane
default when you care about debugging and reliable backtraces, and
makes debugging/profiling with bpf easier.
-
8a3900a3
by Aaron Allen at 2026-01-07T10:27:57-05:00
[26705] Include TyCl instances in data fam iface entry
Ensures dependent modules are recompiled when the class instances for a
data family instance change.
resolves #26705
-
a0b980af
by Cheng Shao at 2026-01-07T10:28:38-05:00
hadrian: remove unused Hp2Ps/Hpc builders
This patch removes the Hp2Ps/Hpc builders from hadrian, they are
unused in the build system. Note that the hp2ps/hpc programs are still
built and not affected.
-
50a58757
by Cheng Shao at 2026-01-07T10:29:20-05:00
hadrian: only install js files to libdir for wasm/js targets
There are certain js files required for wasm/js targets to work, and
previously hadrian would install those js files to libdir
unconditionally on other targets as well. This could be a minor
annoyance for packagers especially when the unused js files contain
shebangs that interfere with the packaging process. This patch makes
hadrian only selectively install the right js files for the right
targets.
Co-authored-by: Codex <codex@openai.com>
-
da40e553
by Simon Peyton Jones at 2026-01-07T10:30:00-05:00
Add flavour transformer assertions_stage1
This allows us to enable -DDEBUG assertions in the stage1 compiler
-
ec3cf767
by Cheng Shao at 2026-01-08T06:24:31-05:00
make: remove unused Makefiles from legacy make build system
This patch removes unused Makefiles from legacy make build system; now
they are never used by hadrian in any way, and they already include
common boilerplate mk files that are long gone in the make build
system removal, hence the housecleaning.
Co-authored-by: Codex <codex@openai.com>
-
04ea3f83
by Cheng Shao at 2026-01-08T06:25:13-05:00
compiler: use -O3 as LLVM optimization level for ghc -O2
The GHC driver clamps LLVM optimization level to `-O2` due to LLVM
crashes, but those were historical issues many years ago that are no
longer relevant for LLVM versions we support today. This patch changes
the driver to use `-O3` as LLVM optimization level when compiling with
`-O2`, which is a better default when we're willing to trade
compilation time for faster generated code.
-
472df471
by Peter Trommler at 2026-01-08T13:28:54-05:00
Use half-word literals in info tables
With this commit info tables are mapped to the same assembler code
on big-endian and little-endian platforms.
Fixes #26579.
-
393f9c51
by Simon Peyton Jones at 2026-01-08T13:29:35-05:00
Refactor srutOkForBinderSwap
This MR does a small refactor:
* Moves `scrutOkForBinderSwap` and `BinderSwapDecision`
to GHC.Core.Utils
* Inverts the sense of the coercion it returns, which makes
more sense
No effect on behaviour
-
ad76fb0f
by Simon Peyton Jones at 2026-01-08T13:29:36-05:00
Improve case merging
This small MR makes case merging happen a bit more often than
it otherwise could, by getting join points out of the way.
See #26709 and GHC.Core.Utils
Note [Floating join points out of DEFAULT alternatives]
-
4c9395f5
by Cheng Shao at 2026-01-08T13:30:16-05:00
hadrian: remove broken hsc2hs flag when cross compiling to windows
This patch removes the `--via-asm` hsc2hs flag when cross compiling to
windows. With recent llvm-mingw toolchain, it would fail with:
```
x86_64-w64-mingw32-hsc2hs: Cannot combine instructions: [Quad 8,Long 4,Long 241,Ref ".Ltmp1-.Ltmp0"]
```
The hsc2hs default `--cross-compile` logic is slower but works.
-
71fdef55
by Simon Peyton Jones at 2026-01-08T13:30:57-05:00
Try harder to keep the substitution empty
Avoid unnecessary cloning of variables in the Simplifier.
Addresses #26724,
See Note [Keeping the substitution empty]
We get some big wins in compile time
Metrics: compile_time/bytes allocated
-------------------------------------
Baseline
Test Metric value New value Change
----------------------------------------------------------------------------
CoOpt_Singletons(normal) ghc/alloc 721,544,088 692,174,216 -4.1% GOOD
LargeRecord(normal) ghc/alloc 1,268,031,157 1,265,168,448 -0.2%
T14766(normal) ghc/alloc 918,218,533 688,432,296 -25.0% GOOD
T15703(normal) ghc/alloc 318,103,629 306,638,016 -3.6% GOOD
T17836(normal) ghc/alloc 419,174,584 418,400,824 -0.2%
T18478(normal) ghc/alloc 471,042,976 470,261,376 -0.2%
T20261(normal) ghc/alloc 573,387,162 563,663,336 -1.7%
T24984(normal) ghc/alloc 87,832,666 87,636,168 -0.2%
T25196(optasm) ghc/alloc 1,103,284,040 1,101,376,992 -0.2%
hard_hole_fits(normal) ghc/alloc 224,981,413 224,608,208 -0.2%
geo. mean -0.3%
minimum -25.0%
maximum +0.1%
Metric Decrease:
CoOpt_Singletons
T14766
T15703
-
30341168
by Simon Peyton Jones at 2026-01-08T13:31:38-05:00
Add regression test for #24867
-
1ac1a541
by Julian Ospald at 2026-01-09T02:48:53-05:00
Support statically linking executables properly
Fixes #26434
In detail, this does a number of things:
* Makes GHC aware of 'extra-libraries-static' (this changes the package
database format).
* Adds a switch '-static-external' that will honour 'extra-libraries-static'
to link external system dependencies statically.
* Adds a new field to settings/targets: "ld supports verbatim namespace".
This field is used by '-static-external' to conditionally use '-l:foo.a'
syntax during linking, which is more robust than trying to find the
absolute path to an archive on our own.
* Adds a switch '-fully-static' that is meant as a high-level interface
for e.g. cabal. This also honours 'extra-libraries-static'.
This also attempts to clean up the confusion around library search directories.
At the moment, we have 3 types of directories in the package database
format:
* library-dirs
* library-dirs-static
* dynamic-library-dirs
However, we only have two types of linking: dynamic or static. Given the
existing logic in 'mungeDynLibFields', this patch assumes that
'library-dirs' is really just nothing but a fallback and always
prefers the more specific variants if they exist and are non-empty.
Conceptually, we should be ok with even just one search dirs variant.
Haskell libraries are named differently depending on whether they're
static or dynamic, so GHC can conveniently pick the right one depending
on the linking needs. That means we don't really need to play tricks
with search paths to convince the compiler to do linking as we want it.
For system C libraries, the convention has been anyway to place static and
dynamic libs next to each other, so we need to deal with that issue
anyway and it is outside of our control. But this is out of the scope
of this patch.
This patch is backwards compatible with cabal. Cabal should however
be patched to use the new '-fully-static' switch.
-
ad3c808d
by Julian Ospald at 2026-01-09T02:48:53-05:00
Warn when "-dynamic" is mixed with "-staticlib"
-
322dd672
by Matthew Pickering at 2026-01-09T02:49:35-05:00
rts: Use INFO_TABLE_CONSTR for stg_dummy_ret_closure
Since the closure type is CONSTR_NOCAF, we need to use INFO_TABLE_CONSTR
to populate the constructor description field (this crashes ghc-debug
when decoding AP_STACK frames sometimes)
Fixes #26745
-
039bac4c
by Ben Gamari at 2026-01-09T20:22:16-05:00
ghc-internal: Move STM utilities out of GHC.Internal.Conc.Sync
This is necessary to avoid an import cycle on Windows when importing
`GHC.Internal.Exception.Context` in `GHC.Internal.Conc.Sync`.
On the road to address #25365.
-
8c389e8c
by Ben Gamari at 2026-01-09T20:22:16-05:00
base: Capture backtrace from throwSTM
Implements core-libraries-committee#297.
Fixes #25365.
-
e1ce1fc3
by Ben Gamari at 2026-01-09T20:22:16-05:00
base: Annotate rethrown exceptions in catchSTM with WhileHandling
Implements core-libraries-committee#298
-
c4ebdbdf
by Cheng Shao at 2026-01-09T20:23:06-05:00
compiler: make getPrim eagerly evaluate its result
This commit makes `GHC.Utils.Binary.getPrim` eagerly evaluate its
result, to avoid accidental laziness when future patches build other
binary parsers using `getPrim`.
-
66a0c4f7
by Cheng Shao at 2026-01-09T20:23:06-05:00
compiler: implement fast get/put for Word16/Word32/Word64
Previously, `GHC.Utils.Binary` contains `get`/`put` functions for
`Word16`/`Word32`/`Word64` which always loads and stores them as
big-endian words at a potentially unaligned address. The previous
implementation is based on loads/stores of individual bytes and
concatenating bytes with bitwise operations, which currently cannot be
fused to a single load/store operation by GHC.
This patch implements fast `get`/`put` functions for
`Word16`/`Word32`/`Word64` based on a single memory load/store, with
an additional `byteSwap` operation on little-endian hosts. It is based
on unaligned load/store primops added since GHC 9.10, and we already
require booting with at least 9.10, so it's about time to switch to
this faster path.
-
641ec3f0
by Simon Peyton Jones at 2026-01-09T20:23:55-05:00
Fix scoping errors in specialisation
Using -fspecialise-aggressively in #26682 showed up a couple of
subtle errors in the type-class specialiser.
* dumpBindUDs failed to call `deleteCallsMentioning`, resulting in a
call that mentioned a dictionary that was not in scope. This call
has been missing since 2009!
commit c43c981705ec33da92a9ce91eb90f2ecf00be9fe
Author: Simon Peyton Jones <simonpj@microsoft.com>
Date: Fri Oct 23 16:15:51 2009 +0000
Fixed by re-combining `dumpBindUDs` and `dumpUDs`.
* I think there was another bug involving the quantified type
variables in polymorphic specialisation. In any case I refactored
`specHeader` and `spec_call` so that the former looks for the
extra quantified type variables rather than the latter. This
is quite a worthwhile simplification: less code, easier to grok.
Test case in simplCore/should_compile/T26682,
brilliantly minimised by @sheaf.
-
2433e91d
by Cheng Shao at 2026-01-09T20:24:43-05:00
compiler: change sectionProtection to take SectionType argument
This commit changes `sectionProtection` to only take `SectionType`
argument instead of whole `Section`, since it doesn't need the Cmm
section content anyway, and it can then be called in parts of NCG
where we only have a `SectionType` in scope.
-
e5926fbe
by Cheng Shao at 2026-01-09T20:24:43-05:00
compiler: change isInitOrFiniSection to take SectionType argument
This commit changes `isInitOrFiniSection` to only take `SectionType`
argument instead of whole `Section`, since it doesn't need the Cmm
section content anyway, and it can then be called in parts of NCG
where we only have a `SectionType` in scope. Also marks it as
exported.
-
244d57d7
by Cheng Shao at 2026-01-09T20:24:43-05:00
compiler: fix split sections on windows
This patch fixes split sections on windows by emitting the right
COMDAT section header in NCG, see added comment for more explanation.
Fix #26696 #26494.
-------------------------
Metric Decrease:
LargeRecord
T9675
size_hello_artifact
size_hello_artifact_gzip
size_hello_unicode
size_hello_unicode_gzip
Metric Increase:
T13035
-------------------------
Co-authored-by: Codex <codex@openai.com>
-
182f3d0f
by Cheng Shao at 2026-01-09T20:25:28-05:00
iserv: add comment about -fkeep-cafs
-
49675b69
by Matthew Craven at 2026-01-09T20:26:14-05:00
Account for "stupid theta" in demand sig for DataCon wrappers
Fixes #26748.
-
f3c18890
by Samuel Thibault at 2026-01-10T15:48:22+01:00
hurd: Fix getExecutablePath build
3939a8bf93e27 ("GNU/Hurd: Add getExecutablePath support") added using
/proc/self/exe for GNU/Hurd but missed adding the required imports for
the corresponding code.
-
7f15bd15
by Samuel Thibault at 2026-01-12T07:16:25-05:00
Fix the OS string encoding for GNU/Hurd
Following https://github.com/haskell/cabal/pull/9434/files , and as seen
in the various gnu_HOST_OS usages in the source code, it is expected that
GNU/Hurd is advertised as "gnu", like the autotools do.
-
1db2f240
by Andrew Lelechenko at 2026-01-12T07:17:06-05:00
Add since annotation for Data.Bifoldable1
Fixes #26432
-
e038a383
by Sven Tennie at 2026-01-12T07:17:49-05:00
Ignore Windows CI tool directories in Git
Otherwise, we see thousands of changes in `git status` which is very
confusing to work with.
-
023c301c
by sheaf at 2026-01-13T04:57:30-05:00
Don't re-use stack slots for growing registers
This commit avoids re-using a stack slot for a register that has grown
but already had a stack slot.
For example, suppose we have stack slot assigments
%v1 :: FF64 |-> StackSlot 0
%v2 :: FF64 |-> StackSlot 1
Later, we start using %v1 at a larger format (e.g. F64x2) and we need
to spill it again. Then we **must not** use StackSlot 0, as a spill
at format F64x2 would clobber the data in StackSlot 1.
This can cause some fragmentation of the `StackMap`, but that's probably
OK.
Fixes #26668
-
d0966e64
by fendor at 2026-01-13T04:58:11-05:00
Remove `traceId` from ghc-pkg executable
-
20d7efec
by Simon Peyton Jones at 2026-01-13T12:41:22-05:00
Make SpecContr rules fire a bit later
See #26615 and Note [SpecConstr rule activation]
-
8bc4eb8c
by Andrew Lelechenko at 2026-01-13T12:42:03-05:00
Upgrade mtl submodule to 2.3.2
Fixes #26656
-
c94aaacd
by Cheng Shao at 2026-01-13T12:42:44-05:00
compiler: remove iserv and only use on-demand external interpreter
This patch removes `iserv` from the tree completely. Hadrian would no
longer build or distribute `iserv`, and the GHC driver would use the
on-demand external interpreter by default when invoked with
`-fexternal-interpreter`, without needing to specify `-pgmi ""`. This
has multiple benefits:
- It allows cleanup of a lot of legacy hacks in the hadrian codebase.
- It paves the way for running cross ghc's iserv via cross emulator
(#25523), fixing TH/ghci support for cross targets other than
wasm/js.
-
c1fe0097
by Peter Trommler at 2026-01-14T03:54:49-05:00
PPC NCG: Fix shift right MO code
The shift amount in shift right [arithmetic] MOs is machine word
width. Therefore remove unnecessary zero- or sign-extending of
shift amount.
It looks harmless to extend the shift amount argument because the
shift right instruction uses only the seven lowest bits (i. e. mod 128).
But now we have a conversion operation from a smaller type to word width
around a memory load at word width. The types are not matching up but
there is no check done in CodeGen. The necessary conversion from word
width down to the smaller width would be translated into a no-op on
PowerPC anyway. So all seems harmless if it was not for a small
optimisation in getRegister'.
In getRegister' a load instruction with the smaller width of the
conversion operation was generated. This loaded the most significant
bits of the word in memory on a big-endian platform. These bits were
zero and hence shift right was used with shift amount zero and not one
as required in test Sized.
Fixes #26519
-
2dafc65a
by Cheng Shao at 2026-01-14T03:55:31-05:00
Tree-wide cleanup of cygwin logic
GHC has not supported cygwin for quite a few years already, and will
not resume support in the forseeable future. The only supported
windows toolchain is clang64/clangarm64 of the msys2 project. This
patch cleans up the unused cygwin logic in the tree.
Co-authored-by: Codex <codex@openai.com>
-
66b96e2a
by Teo Camarasu at 2026-01-14T03:56:13-05:00
Set default eventlog-flush-interval to 5s
Resolves #26707
-
d0254579
by Andrew Lelechenko at 2026-01-14T03:56:53-05:00
Document when -maxN RTS option was added
-
f25e2b12
by Cheng Shao at 2026-01-14T11:10:39-05:00
testsuite: remove obsolete --ci option from the testsuite driver
This patch removes the obsolete `--ci` option from the testsuite
driver: neither the CI scripts nor hadrian ever invokes the testsuite
driver with `--ci`, and the perf notes are always fetched to the
`refs/notes/perf` local reference anyway.
-
7964763b
by Julian Ospald at 2026-01-14T11:11:31-05:00
Fix fetch_cabal
* download cabal if the existing one is of an older version
* fix FreeBSD download url
* fix unpacking on FreeBSD
-
6b0129c1
by Julian Ospald at 2026-01-14T11:11:31-05:00
Bump toolchain in CI
-
0f53ccc6
by Julian Ospald at 2026-01-14T11:11:31-05:00
Use libffi-clib
Previously, we would build libffi via hadrian
and bundle it manually with the GHC bindist.
This now moves all that logic out of hadrian
and allows us to have a clean Haskell package
to build and link against and ship it without
extra logic.
This patch still retains the ability to link
against a system libffi.
The main reason of bundling libffi was that on
some platforms (e.g. FreeBSD and Mac), system libffi
is not visible to the C toolchain by default,
so users would require settings in e.g. cabal
to be able to compile anything.
This adds the submodule libffi-clib to the repository.
-
5e1cd595
by Peng Fan at 2026-01-14T11:12:26-05:00
NCG/LA64: add support for la664 micro architecture
Add '-mla664' flag to LA664, which has some new features:
atomic instructions, dbar hints, etc.
'LA464' is the default so that unrecognized instructions are not
generated.
-
c56567ec
by Simon Peyton Jones at 2026-01-15T23:19:04+00:00
Add evals for strict data-con args in worker-functions
This fixes #26722, by adding an eval in a worker for
arguments of strict data constructors, even if the
function body uses them strictly.
See (WIS1) in Note [Which Ids should be strictified]
I took the opportunity to make substantial improvements in the
documentation for call-by-value functions. See especially
Note [CBV Function Ids: overview] in GHC.Types.Id.Info
Note [Which Ids should be CBV candidates?] ditto
Note [EPT enforcement] in GHC.Stg.EnforceEpt
among others.
-
9719ce5d
by Simon Peyton Jones at 2026-01-15T23:19:04+00:00
Improve `interestingArg`
This function analyses a function's argument to see if it is
interesting enough to deserve an inlining discount. Improvements
for
* LitRubbish arguments
* exprIsExpandable arguments
See Note [Interesting arguments] which is substantially rewritten.
-
7b616b9f
by Cheng Shao at 2026-01-16T06:45:00-05:00
compiler: fix regression when compiling foreign stubs in the rts unit
This patch fixes a regression when compiling foreign stubs in the rts
unit introduced in 05e25647f72bc102061af3f20478aa72bff6ff6e. A simple
revert would fix it, but it's better to implement a proper fix with
comment for better understanding of the underlying problem, see the
added comment for explanation.
Co-authored-by: Codex <codex@openai.com>
-
c343ef64
by Sylvain Henry at 2026-01-16T06:45:51-05:00
base: remove GHC.JS.Prim.Internal.Build (#23432)
See accepted CLC proposal https://github.com/haskell/core-libraries-committee/issues/329
-
29c0aceb
by Simon Peyton Jones at 2026-01-16T17:18:11-05:00
Improve newtype unwrapping
Ticket #26746 describes several relatively-minor shortcomings of newtype
unwrapping. This MR addresses them, while also (arguably) simplifying
the code a bit.
See new Note [Solving newtype equalities: overview]
and Note [Decomposing newtype equalities]
and Note [Eager newtype decomposition]
and Note [Even more eager newtype decomposition]
For some reason, on Windows only, runtime allocations decrease for test
T5205 (from 52k to 48k). I have not idea why. No change at all on Linux.
I'm just going to accept the change. (I saw this same effect in another
MR so I think it's a fault in the baseline.)
Metric Decrease:
T5205
-
8b59e62c
by Andreas Klebinger at 2026-01-16T17:18:52-05:00
testsuite: Widen acceptance window for T5205.
Fixes #26782
-
9e5e0234
by mangoiv at 2026-01-17T06:03:03-05:00
add a new issue template for getting verified
To reduce spam created by new users, we will in future not grant
any rights but reporting issues to new users. That is why we will
have to be able to verify them. The added issue template serves that
purpose.
-
b18b2c42
by Cheng Shao at 2026-01-17T06:03:44-05:00
llvm: fix split sections for llvm backend
This patch fixes split sections for llvm backend:
- Pass missing `--data-sections`/`--function-sections` flags to
llc/opt.
- Use `@llvm.compiler.used` instead of `@llvm.used` to avoid sections
being unnecessarily retained at link-time.
Fixes #26770.
-------------------------
Metric Decrease:
libdir
size_hello_artifact
size_hello_unicode
-------------------------
Co-authored-by: Codex <codex@openai.com>
-
ebf66f67
by Cheng Shao at 2026-01-17T13:16:50-05:00
Update autoconf scripts
Scripts taken from autoconf a2287c3041a3f2a204eb942e09c015eab00dc7dd
-
598624b9
by Andreas Klebinger at 2026-01-17T13:17:32-05:00
CString.hs: Update incorrect comment.
Fixes #26322
-
eea2036b
by Cheng Shao at 2026-01-18T10:00:49-05:00
libraries: bump haskeline submodule to 0.8.4.1
This patch bumps the haskeline submodule to 0.8.4.1 which includes an
important fix for an ANSI handling bug on Windows
(https://github.com/haskell/haskeline/pull/126).
-
87d8f6c2
by Cheng Shao at 2026-01-18T10:01:30-05:00
hadrian: replace default -H32m/-H64m with -O64M to improve mutator productivity
Most hadrian build flavours pass `-H32m`/`-H64m` to GHC as
conventional wisdom to improve mutator productivity and reduce GC
overhead. They were inherited from the legacy Make build system, and
there used to be make flags to instrument a build process with
`-Rghc-timing` option to collect GC stats of each GHC run from stderr.
It's time to revisit whether there are better defaults for
`-H32m`/`-H64m`, and this patch changes it to `-O64M` which indeed
improves mutator productivity based on real statistics. `-O64M` is
more aggressive than `-H64m`; it allows the old generation to grow to
at least 64M before triggering major GC and reduces major GC runs.
The stats of a clean build with `validate` flavour and `-H64m`:
```
h64m.log
matched RTS stat lines: 5499
sum MUT cpu : 2400.808 s
sum GC cpu : 1378.292 s
sum MUT elapsed : 2788.253 s
sum GC elapsed : 1389.233 s
GC/MUT cpu ratio : 0.574 (GC is 57.4% of MUT)
GC/MUT elapsed ratio : 0.498 (GC is 49.8% of MUT)
GC fraction of (MUT+GC) cpu : 36.5%
GC fraction of (MUT+GC) elapsed : 33.3%
per-line GC/MUT cpu ratio: median 0.691, p90 1.777
per-line GC/MUT elapsed ratio: median 0.519, p90 1.081
```
The stats of a clean build with `validate` flavour and `-O64M`:
```
o64m.log
matched RTS stat lines: 5499
sum MUT cpu : 2377.383 s
sum GC cpu : 1127.146 s
sum MUT elapsed : 2758.857 s
sum GC elapsed : 1135.587 s
GC/MUT cpu ratio : 0.474 (GC is 47.4% of MUT)
GC/MUT elapsed ratio : 0.412 (GC is 41.2% of MUT)
GC fraction of (MUT+GC) cpu : 32.2%
GC fraction of (MUT+GC) elapsed : 29.2%
per-line GC/MUT cpu ratio: median 0.489, p90 1.099
per-line GC/MUT elapsed ratio: median 0.367, p90 0.806
```
Mutator time is roughly in the same ballpark, but GC CPU time has
reduced by 18.22%, and mutator productivity has increased from 63.5%
to 67.8%.
-
8372e13d
by Cheng Shao at 2026-01-18T10:02:12-05:00
rts: remove unused .def files from rts/win32
This patch removes unused .def files from `rts/win32`, given we don't
build .dll files for rts/ghc-internal/ghc-prim at all. Even when we
resurrect win32 dll support at some point in the future, these .def
files still contain incorrect symbols anyway and won't be of any use.
-
f6af485d
by Cheng Shao at 2026-01-18T10:03:19-05:00
.gitmodules: use gitlab mirror for the libffi-clib submodule
This patch fixes .gitmodules to use the gitlab mirror for the
libffi-clib submodule, to make it coherent with other submodules that
allow ghc developers to experiment with wip branches in submodules for
ghc patches. Fixes #26783.
-
41432d25
by Cheng Shao at 2026-01-18T10:05:13-05:00
hadrian: remove the horrible i386 speedHack
When hadrian builds certain rts objects for i386, there's a horrible
speedHack that forces -fno-PIC even for dynamic ways of those objects.
This is not compatible with newer versions of gcc/binutils as well as
clang/lld, and this patch removes it. Fixes #26792.
-
323eb8f0
by Cheng Shao at 2026-01-18T21:48:19-05:00
hadrian: enable split sections for cross stage0
This patch fixes a minor issue with `splitSectionsArgs` in hadrian:
previously, it's unconditionally disabled for stage0 libraries because
it's not going to be shipped in the final bindists. But it's only true
when not cross compiling. So for now we also need to enable it for
cross stage0 as well.
-
3fadfefe
by Andreas Klebinger at 2026-01-18T21:49:01-05:00
RTS: Document -K behaviour better
-
30f442a9
by Teo Camarasu at 2026-01-20T13:57:26-05:00
base: don't expose GHC.Num.{BigNat, Integer, Natural}
We no longer expose GHC.Num.{BigNat, Integer, Natural} from base instead users should get these modules from ghc-bignum.
We make this change to insulate end users from changes to GHC's implementation of big numbers.
Implements CLC proposal 359: https://github.com/haskell/core-libraries-committee/issues/359
-
75a9053d
by Teo Camarasu at 2026-01-20T13:58:07-05:00
base: deprecate GHC internals in GHC.Num
Implements CLC proposal: https://github.com/haskell/core-libraries-committee/issues/360
-
9534b032
by Andreas Klebinger at 2026-01-20T13:58:50-05:00
ghc-experimental: Update Changelog
I tried to reconstruct a high level overview of the changes and when
they were made since we introduced it.
Fixes #26506
Co-authored-by: Teo Camarasu <teofilcamarasu@gmail.com>
-
346f2f5a
by Cheng Shao at 2026-01-20T13:59:30-05:00
hadrian: remove RTS options in ghc-in-ghci flavour
This patch removes the RTS options passed to ghc in ghc-in-ghci
flavour, to workaround command line argument handling issue in
hls/hie-boot that results in `-O64M` instead of `+RTS -O64M -RTS`
being passed to ghc. It's not a hadrian bug per se, since ghc's own
ghc-in-ghci multi repl works fine, but we should still make sure HLS
works. Closes #26801.
-
759fd15a
by Andreas Klebinger at 2026-01-21T16:05:28-05:00
Don't build GHC with -Wcompat
Without bumping the boot compiler the warnings it produces are often not
actionable leading to pointless noise.
Fixes #26800
-
3172db94
by Torsten Schmits at 2026-01-21T16:06:11-05:00
Use the correct field of ModOrigin when formatting error message listing hidden reexports
-
485c12b2
by Cheng Shao at 2026-01-21T16:06:54-05:00
Revert "hadrian: handle findExecutable "" gracefully"
This reverts commit 1e5752f64a522c4025365856d92f78073a7b3bba. The
underlying issue has been fixed in
https://github.com/haskell/directory/commit/75828696e7145adc09179111a0d631b9a09963a4
and present since 1.3.9.0, and hadrian directory lower bound is
1.3.9.0, so we can revert our own in house hack now.
-
5efb58dc
by Cheng Shao at 2026-01-21T16:07:36-05:00
rts: fix typo in TICK_ALLOC_RTS
This patch fixes a typo in the `TICK_ALLOC_RTS` macro, the original
`bytes` argument was silently dropped. The Cmm code has its own
version of `TICK_ALLOC_RTS` not affected by this typo, it affected the
C RTS, and went unnoticed because the variable `n` happened to also be
available at its call site. But the number was incorrect. Also fixes
its call site since `WDS()` is not available in C.
-
c406ea69
by Cheng Shao at 2026-01-21T16:07:36-05:00
rts: remove broken & unused ALLOC_P_TICKY
This patch removes the `ALLOC_P_TICKY` macro from the rts, it's
unused, and its expanded code is already broken.
-
34a27e20
by Simon Peyton Jones at 2026-01-21T16:08:17-05:00
Make the implicit-parameter class have representational role
This MR addresses #26737, by making the built-in class IP
have a representational role for its second parameter.
See Note [IP: implicit parameter class] in
ghc-internal:GHC.Internal.Classes.IP
In fact, IP is (unfortunately, currently) exposed by
base:GHC.Base, so we ran a quick CLC proposal to
agree the change:
https://github.com/haskell/core-libraries-committee/issues/385
Some (small) compilations get faster because they only need to
load (small) interface file GHC.Internal.Classes.IP.hi,
rather than (large) GHC.Internal.Classes.hi.
Metric Decrease:
T10421
T12150
T12425
T24582
T5837
T5030
-
ca79475f
by Cheng Shao at 2026-01-21T16:09:00-05:00
testsuite: avoid re.sub in favor of simple string replacements
This patch refactors the testsuite driver and avoids the usage of
re.sub in favor of simple string replacements when possible. The
changes are not comprehensive, and there are still a lot of re.sub
usages lingering around the tree, but this already addresses a major
performance bottleneck in the testsuite driver that might has to do
with quadratic or worse slowdown in cpython's regular expression
engine when handling certain regex patterns with large strings.
Especially on i386, and i386 jobs are the bottlenecks of all full-ci
validate pipelines!
Here are the elapsed times of testing x86_64/i386 with -j48 before
this patch:
x86_64: `Build completed in 6m06s`
i386: `Build completed in 1h36m`
And with this patch:
x86_64: `Build completed in 4m55s`
i386: `Build completed in 4m23s`
Fixes #26786.
Co-authored-by: Codex <codex@openai.com>
-
88c93796
by Zubin Duggal at 2026-01-21T16:09:42-05:00
ghc-toolchain: Also configure windres on non-windows platforms.
It may be needed for cross compilation.
Fixes #24588
-
9788c0ec
by Cheng Shao at 2026-01-21T16:10:24-05:00
ghci: print external interpreter trace messages to stderr instead of stdout
This patch makes ghci print external interpreter trace messages to
stderr instead of stdout, which is a much saner choice for diagnostic
information. Closes #26807.
-
0491f08a
by Sylvain Henry at 2026-01-22T03:44:26-05:00
GC: don't use CAS without PARALLEL_GC on
If we're not using the parallel GC, there is no reason to do a costly
CAS. This was flagged as taking time in a perf profile.
-
211a8f56
by Sylvain Henry at 2026-01-22T03:44:26-05:00
GC: suffix parallel GC with "par" instead of "thr"
Avoid some potential confusion (see discussion in !15351).
-
77a23cbd
by fendor at 2026-01-22T03:45:08-05:00
Remove blanket ignore that covers libraries/
-
18bf7f5c
by Léana Jiang at 2026-01-22T08:58:45-05:00
doc: update Flavour type in hadrian user-settings
-
3d5a1365
by Cheng Shao at 2026-01-22T08:59:28-05:00
hadrian: add missing notCross predicate for stage0 -O0
There are a few hard-coded hadrian args that pass -O0 when compiling
some heavy modules in stage0, which only makes sense when not
cross-compiling and when cross-compiling we need properly optimized
stage0 packages. So this patch adds the missing `notCross` predicate
in those places.
-
ee937134
by Matthew Pickering at 2026-01-22T09:00:10-05:00
Fix ghc-experimental GHC.Exception.Backtrace.Experimental module
This module wasn't added to the cabal file so it was never compiled or
included in the library.
-
1b490f5a
by Zubin Duggal at 2026-01-22T09:00:53-05:00
hadrian: Add ghc-{experimental,internal}.cabal to the list of dependencies of the doc target
We need these files to detect the version of these libraries
Fixes #26738
-
cdb74049
by Cheng Shao at 2026-01-22T14:52:36-05:00
rts: avoid Cmm loop to initialize Array#/SmallArray#
Previously, `newArray#`/`newSmallArray#` called an RTS C function to
allocate the `Array#`/`SmallArray#`, then used a Cmm loop to
initialize the elements. Cmm doesn't have native for-loop so the code
is a bit awkward, and it's less efficient than a C loop, since the C
compiler can effectively vectorize the loop with optimizations.
So this patch moves the loop that initializes the elements to the C
side. `allocateMutArrPtrs`/`allocateSmallMutArrPtrs` now takes a new
`init` argument and initializes the elements if `init` is non-NULL.
-
4c784f00
by Cheng Shao at 2026-01-22T14:53:19-05:00
Fix testsuite run for +ipe flavour transformer
This patch makes the +ipe flavour transformer pass the entire
testsuite:
- An RTS debug option `-DI` is added, the IPE trace information is now
only printed with `-DI`. The test cases that do require IPE trace
are now run with `-DI`.
- The testsuite config option `ghc_with_ipe` is added, enabled when
running the testsuite with `+ipe`, which skips a few tests that are
sensitive to eventlog output, allocation patterns etc that can fail
under `+ipe`.
This is the first step towards #26799.
Co-authored-by: Codex <codex@openai.com>
-
be8e5236
by Ben Gamari at 2026-01-23T03:28:45-05:00
hadrian: Bump QuickCheck upper bound
This patch bumps QuickCheck upper bound to 2.18. selftest rule
manually tested to work with current latest QuickCheck-2.17.1.0.
-
5aa328fb
by Zubin Duggal at 2026-01-23T03:29:30-05:00
Add genindex to index.rst. This adds a link to the index in the navigation bar.
Fixes #26437
-
917ab8ff
by Oleg Grenrus at 2026-01-23T10:52:55-05:00
Export labelThread from Control.Concurrent
-
3f5e8d80
by Cheng Shao at 2026-01-23T10:53:37-05:00
ci: only push perf notes on master/release branches
This patch fixes push_perf_notes logic in ci.sh to only push perf
notes on master/release branches. We used to unconditionally push perf
notes even in MRs, but the perf numbers in the wip branches wouldn't
be used as baseline anyway, plus this is causing a space leak in the
ghc-performance-notes repo. See #25317 for the perf notes repo size
problem.
Co-authored-by: Codex <codex@openai.com>
-
414b9593
by Cheng Shao at 2026-01-24T07:11:51-05:00
ci: remove duplicate keys in .gitlab-ci.yml
This patch removes accidentally duplicate keys in `.gitlab-ci.yml`.
The YAML spec doesn't allow duplicate keys in the first place, and
according to GitLab docs
(https://docs.gitlab.com/ci/yaml/yaml_optimization/#anchors), the
latest key overrides the earlier entries.
-
e5cb5491
by Cheng Shao at 2026-01-24T07:12:34-05:00
hadrian: drop obsolete configure/make builder logic for libffi
This patch drops obsolete hadrian logic around `Configure
libffiPath`/`Make libffiPath` builders, they are no longer needed
after libffi-clib has landed. Closes #26815.
-
2d160222
by Simon Hengel at 2026-01-24T07:13:17-05:00
Fix typo in roles.rst
-
56db94f7
by Peter Trommler at 2026-01-26T11:26:18+01:00
PPC NCG: Generate clear right insn at arch width
The clear right immediate (clrrxi) is only available in word and
doubleword width. Generate clrrxi instructions at architecture
width for all MachOp widths.
Fixes #24145
-
5957a8ad
by Wolfgang Jeltsch at 2026-01-27T06:11:40-05:00
Add operations for obtaining operating-system handles
This contribution implements CLC proposal #369. It adds operations for
obtaining POSIX file descriptors and Windows handles that underlie
Haskell handles. Those operating system handles can also be obtained
without such additional operations, but this is more involved and, more
importantly, requires using internals.
-
86a0510c
by Greg Steuck at 2026-01-27T06:12:34-05:00
Move flags to precede patterns for grep and read files directly
This makes the tests pass with non-GNU (i.e. POSIX-complicant) tools.
There's no reason to use cat and pipe where direct file argument works.
-
50761451
by Cheng Shao at 2026-01-27T21:51:23-05:00
ci: update darwin boot ghc to 9.10.3
This patch updates darwin boot ghc to 9.10.3, along with other related
updates, and pays off some technical debt here:
- Update `nixpkgs` and use the `nixpkgs-25.05-darwin` channel.
- Update the `niv` template.
- Update LLVM to 21 and update `llvm-targets` to reflect LLVM 21
layout changes for arm64/x86_64 darwin targets.
- Use `stdenvNoCC` to prevent nix packaged apple sdk from being used
by boot ghc, and manually set `DEVELOPER_DIR`/`SDKROOT` to enforce
the usage of system-wide command line sdk for macos.
- When building nix derivation for boot ghc, run `configure` via the
`arch` command so that `configure` and its subprocesses pick up the
manually specified architecture.
- Remove the previous horrible hack that obliterates `configure` to
make autoconf test result in true. `configure` now properly does its
job.
- Remove the now obsolete configure args and post install settings
file patching logic.
- Use `scheme-small` for texlive to avoid build failures in certain
unused texlive packages, especially on x86_64-darwin.
-
94dcd15e
by Matthew Pickering at 2026-01-27T21:52:05-05:00
Evaluate backtraces for "error" exceptions at the moment they are thrown
See Note [Capturing the backtrace in throw] and
Note [Hiding precise exception signature in throw] which explain the
implementation.
This commit makes `error` and `throw` behave the same with regard to
backtraces. Previously, exceptions raised by `error` would not contain
useful IPE backtraces.
I did try and implement `error` in terms of `throw` but it started to
involve putting diverging functions into hs-boot files, which seemed to
risky if the compiler wouldn't be able to see if applying a function
would diverge.
CLC proposal: https://github.com/haskell/core-libraries-committee/issues/383
Fixes #26751
-
ef35e3ea
by Teo Camarasu at 2026-01-27T21:52:46-05:00
ghc-internal: move all Data instances to Data.Data
Most instances of Data are defined in GHC.Internal.Data.Data.
Let's move all remaining instance there.
This moves other modules down in the dependency hierarchy allowing for
more parallelism, and it decreases the likelihood that we would need to
load this heavy .hi file if we don't actually need it.
Resolves #26830
Metric Decrease:
T12227
T16875
-
5e0ec555
by sheaf at 2026-01-28T06:56:38-05:00
Add test case for #25679
This commit adds the T25679 test case. The test now passes, thanks to
commit 1e53277af36d3f0b6ad5491f70ffc5593a49dcfd.
Fixes #25679
-
f1cd1611
by sheaf at 2026-01-28T06:56:38-05:00
Improve defaulting of representational equalities
This commit makes the defaulting of representational equalities, introduced
in 1e53277a, a little bit more robust. Now, instead of calling the eager
unifier, it calls the full-blown constraint solver, which means that it can
handle some subtle situations, e.g. involving functional dependencies and
type-family injectivity annotations, such as:
type family F a = r | r -> a
type instance F Int = Bool
[W] F beta ~R Bool
-
25edf516
by sheaf at 2026-01-28T06:56:38-05:00
Improve errors for unsolved representational equalities
This commit adds a new field of CtLoc, CtExplanations, which allows the
typechecker to leave some information about what it has done. For the moment,
it is only used to improve error messages for unsolved representational
equalities. The typechecker will now accumulate, when unifying at
representational role:
- out-of-scope newtype constructors,
- type constructors that have nominal role in a certain argument,
- over-saturated type constructors,
- AppTys, e.g. `c a ~R# c b`, to report that we must assume that 'c' has
nominal role in its parameters,
- data family applications that do not reduce, potentially preventing
newtype unwrapping.
Now, instead of having to re-construct the possible errors after the fact,
we simply consult the CtExplanations field.
Additionally, this commit modifies the typechecker error messages that
concern out-of-scope newtype constructors. The error message now depends
on whether we have an import suggestion to provide to the user:
- If we have an import suggestion for the newtype constructor,
the message will be of the form:
The data constructor MkN of the newtype N is out of scope
Suggested fix: add 'MkN' to the import list in the import of 'M'
- If we don't have any import suggestions, the message will be
of the form:
NB: The type 'N' is an opaque newtype, whose constructor is hidden
Fixes #15850, #20289, #20468, #23731, #25949, #26137
-
4d0e6da1
by Simon Peyton Jones at 2026-01-28T06:57:19-05:00
Fix two bugs in short-cut constraint solving
There are two main changes here:
* Use `isSolvedWC` rather than `isEmptyWC` in `tryShortCutSolver`
The residual constraint may have some fully-solved, but
still-there implications, and we don't want them to abort short
cut solving! That bug caused #26805.
* In the short-cut solver, we abandon the fully-solved residual
constraint; but we may thereby lose track of Givens that are
needed, and either report them as redundant or prune evidence
bindings that are in fact needed.
This bug stopped the `constraints` package from compiling;
see the trail in !15389.
The second bug led me to (another) significant refactoring
of the mechanism for tracking needed EvIds. See the new
Note [Tracking needed EvIds] in GHC.Tc.Solver.Solve
It's simpler and much less head-scratchy now.
Some particulars:
* An EvBindsVar now tracks NeededEvIds
* We deal with NeededEvIds for an implication only when it is
fully solved. Much simpler!
* `tryShortCutTcS` now takes a `TcM WantedConstraints` rather than
`TcM Bool`, so that is can plumb the needed EvIds correctly.
* Remove `ic_need` and `ic_need_implic` from Implication (hooray),
and add `ics_dm` and `ics_non_dm` to `IC_Solved`.
Pure refactor
* Shorten data constructor `CoercionHole` to `CH`, following
general practice in GHC.
* Rename `EvBindMap` to `EvBindsMap` for consistency
-
662480b7
by Cheng Shao at 2026-01-28T06:58:00-05:00
ci: use debian validate bindists instead of fedora release bindists in testing stage
This patch changes the `abi-test`, `hadrian-multi` and `perf` jobs in
the full-ci pipeline testing stage to use debian validate bindists
instead of fedora release bindists, to increase pipeline level
parallelism and allow full-ci pipelines to complete earlier. Closes #26818.
-
39581ec6
by Cheng Shao at 2026-01-28T06:58:40-05:00
ci: run perf test with -j$cores
This patch makes the perf ci job compile Cabal with -j$cores to speed
up the job.
-
607b287b
by Wolfgang Jeltsch at 2026-01-28T15:41:53+02:00
Remove `GHC.Desugar` from `base`
`GHC.Desugar` was deprecated and should have been removed in GHC 9.14.
However, the removal was forgotten, although there was a code block that
was intended to trigger a compilation error when the GHC version in use
was 9.14 or later. This code sadly didn’t work, because the
`__GLASGOW_HASKELL__` macro was misspelled as `__GLASGOW_HASKELL`.
-
e8f5a45d
by sterni at 2026-01-29T04:19:18-05:00
users_guide: fix runtime error during build with Sphinx 9.1.0
Appears that pathto is stricter about what it accepts now.
Tested Sphinx 8.2.3 and 9.1.0 on the ghc-9.10 branch.
Resolves #26810.
Co-authored-by: Martin Weinelt <hexa@darmstadt.ccc.de>
-
ce2d62fb
by Jessica Clarke at 2026-01-29T19:48:51-05:00
PPC NCG: Use libcall for 64-bit cmpxchg on 32-bit PowerPC
There is no native instruction for this, and even if there were a
register pair version we could use, the implementation here is assuming
the values fit in a single register, and we end up only using / defining
the low halves of the registers.
Fixes: b4d39adbb5 ("PrimOps: Add CAS op for all int sizes")
Fixes: #23969
-
43d97761
by Michael Karcher at 2026-01-29T19:49:43-05:00
NCG for PPC: add pattern for CmmRegOff to iselExpr64
Closes #26828
-
aeeb4a20
by Matthew Pickering at 2026-01-30T11:42:47-05:00
determinism: Use deterministic map for Strings in TyLitMap
When generating typeable evidence the types we need evidence for all
cached in a TypeMap, the order terms are retrieved from a type map
determines the order the bindings appear in the program.
A TypeMap is quite diligent to use deterministic maps, apart from in the
TyLitMap, which uses a UniqFM for storing strings, whose ordering
depends on the Unique of the FastString.
This can cause non-deterministic .hi and .o files.
An unexpected side-effect is the error message but RecordDotSyntaxFail8
changing. I looked into this with Sam and this change caused the
constraints to be solved in a different order which results in a
slightly different error message. I have accepted the new test, since
the output before was non-deterministic and the new output is consistent
with the other messages in that file.
Fixes #26846
-
9e4d70c2
by Andrew Lelechenko at 2026-01-30T11:43:29-05:00
Upgrade text submodule to 2.1.4
-
631fa5ae
by Recursion Ninja at 2026-01-31T22:30:11+00:00
Decouple `L.S.H.Decls` from importing `GHC.Types.Basic`
Data-types within `GHC.Types.Basic` which describe components of
the AST are migrated to `Language.Haskell.Syntax.Basic`. Related
function definitions are also moved.
Types moved to L.H.S. because they are part of the AST:
* TopLevelFlag
* RuleName
Types moved from L.H.S. to GHC.Hs. because they are not needed in the AST:
* TyConFlavour
* TypeOrData
* NewOrData
Migrated instances:
* `Outputable` instances moved to in `GHC.Utils.Outputable`
* `Binary` instance of `Boxity` moved to to `GHC.Utils.Binary`
* Other `Binary` instances are orphans to be migrated later.
The `OverlapMode` data-type is given a TTG extension point.
The `OverlapFlag` data-type, which depends on `OverlapMode`,
is updated to support `OverlapMode` with a GHC "pass" type paramerter.
In order to avoid module import cycles, `OverlapMode` and `OverlapFlag`
are migrated to new modules (no way around this).
* Migrated `OverlapMode` to new module `Language.Haskell.Syntax.Overlap`
* Migrated `OverlapFlag` to new module `GHC.Hs.Decls.Overlap`
-
9769cc03
by Simon Hengel at 2026-02-01T04:21:03-05:00
Update the documentation for MultiWayIf (fixes #25376)
(so that it matches the implementation)
-
5fc9442a
by Peter Trommler at 2026-02-01T04:21:44-05:00
hadrian: Fix dependency generation for assembler
Assembler files allow # for comments unless in column 1. A modern
cpp for C treats those a preprocessor directives. We tell gcc that
a .S file is assembler with cpp and not C.
Fixes #26819
-
269c4087
by Simon Peyton Jones at 2026-02-01T19:38:10-05:00
Include current phase in the range for rule/unfoldings
This MR fixes a bad loop in the compiler: #26826.
The fix is to add (WAR2) to
Note [What is active in the RHS of a RULE or unfolding?]
in GHC.Core.Opt.Simplify.Utils
-
ddf1434f
by Vladislav Zavialov at 2026-02-01T19:38:52-05:00
Refactor: merge HsMultilineString into HsString (#26860)
Before this patch, HsLit defined two separate constructors to represent
single-line and multi-line strings:
data HsLit x
...
| HsString (XHsString x) FastString
| HsMultilineString (XHsMultilineString x) FastString
I found this to be an unnecessary complication and an obstacle to unifying
HsLit with HsTyLit. Now we use HsString for both kinds of literals.
One user-facing change here is `ppr (HsString st s)` behaving differently for
single-line strings containing newlines:
x = "first line \
\asdf\n\
\second line"
Previously, the literal was fed to `ftext` with its newlines, producing an
ill-formed SDoc. This issue is now addressed by using `split` for both
single-line and multi-line strings:
vcat $ map text $ split '\n' (unpackFS src)
See the parser/should_fail/T26860ppr test.
In addition (and unrelatedly to the main payload of this patch),
drop the unused pmPprHsLit helper.
-
2b4f463c
by Simon Peyton Jones at 2026-02-02T17:32:32+00:00
Remove exprIsCheap from doFloatFromRhs
See #26854 and Note [Float when expandable]
This patch simplifies the code, by removing an extra unnecessary test.
-
9db7f21f
by Brandon Chinn at 2026-02-03T09:15:10-05:00
Refactor: make function patterns exhaustive
Also added missing (==) logic for:
* HsMultilineString
* HsInt{8,16,32}
* HsWord{8,16,32}
-
aa9c5e2c
by Hécate Kleidukos at 2026-02-03T15:58:35-05:00
driver: Hide source paths at verbosity level 1 by default
-
c64cca1e
by mangoiv at 2026-02-03T15:59:29-05:00
ExplicitLevelImports: check staging for types just like for values
Previously, imported types were entirely exempted from staging checks as
the implicit stage persistance assumed to be all imported types to be
well staged. ExplicitLevelImports' change specification, however, does
not do such an exemption. Thus we want to introduce such a check, just
like we have for values.
ExplicitLevelImports does not, however, talk about local names - from
its perspective, we could theoretically keep treating locally introduced
types specially - e.g. an ill-staged used in a quote would only emit a
warning, not an error. To allow for a potential future migration away
from such wrinkles as the staging check in notFound
(see Note [Out of scope might be a staging error]) we consistently do
the strict staging check that we also do for value if ExplicitLevelImports
is on.
Closes #26098
-
5f0dbeb6
by Simon Hengel at 2026-02-03T16:00:12-05:00
Use Haddock formatting in deprecation message of `initNameCache`
-
01ecb612
by Andreas Klebinger at 2026-02-04T09:56:25-05:00
testsuite: Explicitly use utf-8 encoding in rts-includes linter.
Not doing so caused failures on windows, as python failed to pick a
reasonable encoding even with locale set.
Fixes #26850
-
ea0d1317
by Zubin Duggal at 2026-02-04T09:57:06-05:00
Bump transformers submodule to 0.6.3.0
Fixes #26790
-
cbe4300e
by Simon Peyton Jones at 2026-02-05T04:31:04-05:00
Fix subtle bug in GHC.Core.Utils.mkTick
This patch fixes a decade-old bug in `mkTick`, which
could generate type-incorrect code! See the diagnosis
in #26772.
The new code is simpler and easier to understand.
(As #26772 says, I think it could be improved further.)
-
a193a8da
by Simon Peyton Jones at 2026-02-05T04:31:04-05:00
Modify a debug-trace in the Simplifier
...just to show a bit more information.
-
b579dfdc
by Simon Peyton Jones at 2026-02-05T04:31:04-05:00
Fix long-standing interaction between ticks and casts
The code for Note [Eliminate Identity Cases] was simply wrong when
ticks and casts interacted. This patch fixes the interaction.
It was shown up when validating #26772, although it's not the exactly
the bug that's reported by #26772. Nor is it easy to reproduce, hence
no regression test.
-
fac0de1e
by Cheng Shao at 2026-02-05T04:31:49-05:00
libraries: bump Cabal submodule to 3.16.1.0
-
00589122
by Cheng Shao at 2026-02-05T04:31:49-05:00
libraries: bump deepseq submodule to 1.5.2.0
Also:
- Get rid of usage of deprecated `NFData` function instance in the
compiler
- `T21391` still relies on `NFData` function instance, add
`-Wno-deprecations` for the time being.
-
84474c71
by Cheng Shao at 2026-02-05T04:31:50-05:00
libraries: bump directory submodule to 1.3.10.1
-
1a9f4662
by Cheng Shao at 2026-02-05T04:31:50-05:00
libraries: bump exceptions submodule to 0.10.12
-
2e39a340
by Peng Fan at 2026-02-07T03:42:01-05:00
NCG/LA64: adjust register usage to avoid src-register being clobbered
-
9faf1b35
by Teo Camarasu at 2026-02-07T03:42:43-05:00
ghc-internal: Delete unnecessary GHC.Internal.Data.Ix
This module merely re-exports GHC.Internal.Ix. It was copied from
`base` when `ghc-internal` was split, but there is no reason to have
this now. So, let's delete it.
Resolves #26848
-
d112b440
by Sven Tennie at 2026-02-07T10:47:56-05:00
Add cabal.project file to generate-ci
This fixes the HLS setup for our CI code generation script
(generate-ci).
The project file simply makes `generate-ci` of the cabal file
discoverable.
-
5339f6f0
by Andreas Klebinger at 2026-02-07T10:48:40-05:00
CI: Don't collapse test results.
This puts test output back into the primary test log instead of a
subsection removing the need to expand a section to see test results.
While the intention was good in practice the old behaviour mostly wastes time
by requiring expansion of the section.
Fixes #26882
-
0e1cd2e0
by Evan Piro at 2026-02-08T10:35:16-08:00
Linker.MacOS reduce dynflags import
-
1c79a4cd
by Michael Alan Dorman at 2026-02-09T08:11:51-05:00
Remove `extra_src_files` variable from `testsuite/driver/testlib.py`
While reading through the test harness code, I noticed this variable
with a TODO attached that referenced #12223. Although that bug is
closed, it strongly implied that this special-case variable that only
affected a single test was expected to be removed at some point.
I also looked at 3415bcaa0b1903b5e12dfaadb5b774718e406eab---where it
was added---whose commit message suggested that it would have been
desirable to remove it, but that there were special circumstances that
meant it had to remain (though it doesn't elucidate what those special
circumstances are).
However, the special circumstances were mentioned as if the test was
in a different location than is currently is, so I decided to try
changing the test to use the standard `extra_files` mechanism, which
works in local testing.
This also seems like a reasonable time to remove the script that was
originally used in the transition, since it doesn't really serve a
purpose anymore.
-
0020e38a
by Matthew Pickering at 2026-02-09T17:29:14-05:00
determinism: Use a stable sort in WithHsDocIdentifiers binary instance
`WithHsDocIdentifiers` is defined as
```
71 data WithHsDocIdentifiers a pass = WithHsDocIdentifiers
72 { hsDocString :: !a
73 , hsDocIdentifiers :: ![Located (IdP pass)]
74 }
```
This list of names is populated from `rnHsDocIdentifiers`, which calls
`lookupGRE`, which calls `lookupOccEnv_AllNameSpaces`, which calls
`nonDetEltsUFM` and returns the results in an order depending on
uniques.
Sorting the list with a stable sort before returning the interface makes
the output deterministic and follows the approach taken by other fields
in `Docs`.
Fixes #26858
-
89898ce6
by echoumcp1 at 2026-02-09T17:30:01-05:00
Replace putstrln with logMsg in handleSeqHValueStatus
Fixes #26549
-
7c52c4f9
by John Paul Adrian Glaubitz at 2026-02-10T13:52:43-05:00
rts: Switch prim to use modern atomic compiler builtins
The __sync_*() atomic compiler builtins have been deprecated in GCC
for a while now and also don't provide variants for 64-bit values
such as __sync_fetch_and_add_8().
Thus, replace them with the modern __atomic_*() compiler builtins and
while we're at it, also drop the helper macro CAS_NAND() which is now
no longer needed since we stopped using the __sync_*() compiler builtins
altogether.
Co-authored-by: Ilias Tsitsimpis <iliastsi@debian.org>
Fixes #26729
-
cf60850a
by Recursion Ninja at 2026-02-10T13:53:27-05:00
Decoupling L.H.S.Decls from GHC.Types.ForeignCall
- Adding TTG extension point for 'CCallTarget'
- Adding TTG extension point for 'CType'
- Adding TTG extension point for 'Header'
- Moving ForeignCall types that do not need extension
to new L.H.S.Decls.Foreign module
- Replacing 'Bool' parameters with descriptive data-types
to increase clairty and prevent "Boolean Blindness"
-
11a04cbb
by Eric Lee at 2026-02-11T09:20:46-05:00
Derive Semigroup/Monoid for instances believed could be derived in #25871
-
15d9ce44
by Eric Lee at 2026-02-11T09:20:46-05:00
add Ghc.Data.Pair deriving
-
c85dc170
by Evan Piro at 2026-02-11T09:21:45-05:00
Linker.MacOS reduce options import
-
a541dd83
by Chris Wendt at 2026-02-11T16:06:41-05:00
Initialize plugins for `:set +c` in GHCi
Fixes #23110.
-
0f5a73bc
by Cheng Shao at 2026-02-11T16:07:27-05:00
compiler: add Binary Text instance
This patch adds `Binary` instance for strict `Text`, in preparation of
making `Text` usable in certain GHC API use cases (e.g. haddock). This
also introduces `text` as a direct dependency of the `ghc` package.
-
9e58b8a1
by Cheng Shao at 2026-02-11T16:08:10-05:00
ghc-toolchain: add C11 check
This patch partially reverts commit
b8307eab80c5809df5405d76c822bf86877f5960 that removed C99 check in
autoconf/ghc-toolchain. Now we:
- No longer re-implement `FP_SET_CFLAGS_C11` similar to
`FP_SET_CFLAGS_C99` in the past, since autoconf doesn't provide a
convenient `AC_PROG_CC_C11` function. ghc-toolchain will handle it
anyway.
- The Cmm CPP C99 check is relanded and repurposed for C11.
- The C99 logic in ghc-toolchain is relanded and repurposed for C11.
- The C99 check in Stg.h is corrected to check for C11. The obsolete
_ISOC99_SOURCE trick is dropped.
- Usages of `-std=gnu99` in the testsuite are corrected to use
`-std=gnu11`.
Closes #26908.
-
4df0adf6
by Simon Peyton Jones at 2026-02-11T21:50:13-05:00
Simplify the treatment of static forms
This MR implements GHC proposal 732: simplify static forms,
https://github.com/ghc-proposals/ghc-proposals/pull/732
thereby addressing #26556.
See `Note [Grand plan for static forms]` in GHC.Iface.Tidy.StaticPtrTable
The main changes are:
* There is a new, simple rule for (static e), namely that the free
term variables of `e` must be bound at top level. The check is
done in the `HsStatic` case of `GHC.Rename.Expr.rnExpr`
* That in turn substantially simplifies the info that the typechecker
carries around in its type environment. Hooray.
* The desugarer emits static bindings to top level directly; see the
`HsStatic` case of `dsExpr`.
* There is no longer any special static-related magic in the FloatOut
pass. And the main Simplifier pipeline no longer needs a special case
to run FloatOut even with -O0. Hooray.
All this forced an unexpected change to the pattern match checker. It
recursively invokes the main Hs desugarer when it wants to take a look
at a term to spot some special cases (notably constructor applications).
We don't want to emit any nested (static e) bindings to top level a
second time! Yikes.
That forced a modest refactor in GHC.HsToCore.Pmc:
* The `dsl_nablas` field of `DsLclEnv` now has a `NoPmc` case, which says
"I'm desugaring just for pattern-match checking purposes".
* When that flag is set we don't emit static binds.
That in turn forces a cascade of refactoring, but the net effect is an
improvement; less risk of duplicated (even exponential?) work.
See Note [Desugaring HsExpr during pattern-match checking].
10% metric decrease, on some architectures, of compile-time max-bytes-used on T15304.
Metric Decrease:
T15304
-
7922f728
by Teo Camarasu at 2026-02-11T21:50:58-05:00
ghc-internal: avoid depending on GHC.Internal.Exts
This module is mostly just re-exports. It made sense as a user-facing
module, but there's no good reason ghc-internal modules should depend on
it and doing so linearises the module graph
- move considerAccessible to GHC.Internal.Magic
Previously it lived in GHC.Internal.Exts, but it really deserves to live
along with the other magic function, which are already re-exported from .Exts
- move maxTupleSize to GHC.Internal.Tuple
This previously lived in GHC.Internal.Exts but a comment already said it
should be moved to .Tuple
Resolves #26832
-
b6a4a29b
by Eric Lee at 2026-02-11T21:51:55-05:00
Remove unused Semigroup imports to fix GHC 9.14 bootstrapping
-
99d8c146
by Simon Peyton Jones at 2026-02-12T17:36:59+00:00
Fix subtle bug in cast worker/wrapper
See (CWw4) in Note [Cast worker/wrapper].
The true payload is in the change to the definition of
GHC.Types.Id.Info.hasInlineUnfolding
Everthing else is just documentation.
There is a 2% compile time decrease for T13056;
I'll take the win!
Metric Decrease:
T13056
-
530e8e58
by Simon Peyton Jones at 2026-02-12T20:17:23-05:00
Add regression tests for four StaticPtr bugs
Tickets #26545, #24464, #24773, #16981 are all solved by the
recently-landed MR
commit 318ee13bcffa6aa8df42ba442ccd92aa0f7e210c
Author: Simon Peyton Jones <simon.peytonjones@gmail.com>
Date: Mon Oct 20 23:07:20 2025 +0100
Simplify the treatment of static forms
This MR just adds regression tests for them.
-
4157160f
by Cheng Shao at 2026-02-13T06:27:04-05:00
ci: remove unused hlint-ghc-and-base job definition
This patch removes the unused `hlint-ghc-and-base` job definition,
it's never run since !9806. Note that hadrian lint rules still work
locally, so anyone that wishes to run hlint on the codebase can
continue to do so in their local worktree.
-
039f1977
by Cheng Shao at 2026-02-13T06:27:47-05:00
wasm: use import.meta.main for proper distinction of nodejs main modules
This patch uses `import.meta.main` for proper distinction of nodejs
main modules, especially when the main module might be installed as a
symlink. Fixes #26916.
-
14f485ee
by ARATA Mizuki at 2026-02-17T09:09:24+09:00
Support more x86 extensions: AVX-512 {BW,DQ,VL} and GFNI
Also, mark AVX-512 ER and PF as deprecated.
AVX-512 instructions can be used for certain 64-bit integer vector operations.
GFNI can be used to implement bitReverse (currently not used by NCG, but LLVM may use it).
Closes #26406
Addresses #26509
-
016f79d5
by fendor at 2026-02-17T09:16:16-05:00
Hide implementation details from base exception stack traces
Ensure we hide the implementation details of the exception throwing mechanisms:
* `undefined`
* `throwSTM`
* `throw`
* `throwIO`
* `error`
The `HasCallStackBacktrace` should always have a length of exactly 1,
not showing internal implementation details in the stack trace, as these
are vastly distracting to end users.
CLC proposal [#387](https://github.com/haskell/core-libraries-committee/issues/387)
-
4f2840f2
by Brian J. Cardiff at 2026-02-17T17:04:08-05:00
configure: Accept happy-2.2
In Jan 2026 happy-2.2 was released. The most sensible change is https://github.com/haskell/happy/issues/335 which didn't trigger in a fresh build
-
10b4d364
by Duncan Coutts at 2026-02-17T17:04:52-05:00
Fix errors in the documentation of the eventlog STOP_THREAD status codes
Fix the code for BlockedOnMsgThrowTo.
Document all the known historical warts.
Fixes issue #26867
-
c5e15b8b
by Phil de Joux at 2026-02-18T05:07:36-05:00
haddock: use snippets for all list examples
- generate snippet output for docs
- reduce font size to better fit snippets
- Use only directive to guard html snippets
- Add latex snippets for lists
-
d388bac1
by Phil de Joux at 2026-02-18T05:07:36-05:00
haddock: Place the snippet input and output together
- Put the output seemingly inside the example box
-
016fa306
by Samuel Thibault at 2026-02-18T05:08:35-05:00
Fix linking against libm by moving the -lm option
For those systems that need -lm for getting math functions, this is
currently added on the link line very early, before the object files being
linked together. Newer toolchains enable --as-needed by default, which means
-lm is ignored at that point because no object requires a math function
yet. With such toolchains, we thus have to add -lm after the objects, so the
linker actually includes libm in the link.
-
68bd0805
by Teo Camarasu at 2026-02-18T05:09:19-05:00
ghc-internal: Move GHC.Internal.Data.Bool to base
This is a tiny module that only defines bool :: Bool -> a -> a -> a. We can just move this to base and delete it from ghc-internal. If we want this functionality there we can just use a case statement or if-then expression.
Resolves 26865
-
4c40df3d
by fendor at 2026-02-20T10:24:48-05:00
Add optional `SrcLoc` to `StackAnnotation` class
`StackAnnotation`s give access to an optional `SrcLoc` field that
user-added stack annotations can use to provide better backtraces in both error
messages and when decoding the callstack.
We update builtin stack annotations such as `StringAnnotation` and
`ShowAnnotation` to also capture the `SrcLoc` of the current `CallStack`
to improve backtraces by default (if stack annotations are used).
This change is backwards compatible with GHC 9.14.1.
-
fd9aaa28
by Simon Hengel at 2026-02-20T10:25:33-05:00
docs: Fix grammar in explicit_namespaces.rst
-
44354255
by Vo Minh Thu at 2026-02-20T18:53:06-05:00
GHCi: add a :version command.
This looks like:
ghci> :version
GHCi, version 9.11.20240322
This closes #24576.
Co-Author: Markus Läll <markus.l2ll@gmail.com>
-
eab3dbba
by Andreas Klebinger at 2026-02-20T18:53:51-05:00
hadrian/build-cabal: Better respect and utilize -j
* We now respect -j<n> for the cabal invocation to build hadrian rather
than hardcoding -j
* We use the --semaphore flag to ensure cabal/ghc build the hadrian
executable in parallel using the -jsem mechanism.
Saves 10-15s on fresh builds for me.
Fixes #26876
-
55fc7376
by Sven Tennie at 2026-02-24T12:07:57+00:00
Introduce test predicate for libdw
Libdw does only exist on elf-based operating systems and when it has
been configured (via autoconf.)
-
cf9eb550
by Sven Tennie at 2026-02-24T12:08:29+00:00
WIP: Add test for DWARF (libdw) stacktraces
-
d994d113
by Sven Tennie at 2026-02-24T12:12:58+00:00
--enable-dwarf-unwind on CI
Enable it for GHC DWARF builds as the required tools should be around there.