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[Git][ghc/ghc] Pushed new branch wip/fix-darwin-toolchain-cruft
by Cheng Shao (＠TerrorJack) 07 Jan '26

07 Jan '26

Cheng Shao pushed new branch wip/fix-darwin-toolchain-cruft at Glasgow Haskell Compiler / GHC -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/tree/wip/fix-darwin-toolchain-cruft You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][wip/T26707] 73 commits: compiler: remove unused CPP code in foreign stub
by Teo Camarasu (＠teo) 07 Jan '26

07 Jan '26

Teo Camarasu pushed to branch wip/T26707 at Glasgow Haskell Compiler / GHC Commits: 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-…) 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(a)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(a)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(a)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(a)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(a)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(a)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(a)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(a)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 - - - - - f43cc007 by Teo Camarasu at 2026-01-06T19:07:38+00:00 Set default eventlog-flush-interval to 5s Resolves #26707 - - - - - 713 changed files: - .gitattributes - .gitlab-ci.yml - .gitlab/ci.sh - .gitlab/generate-ci/gen_ci.hs - .gitlab/jobs.yaml - .gitlab/rel_eng/fetch-gitlab-artifacts/fetch_gitlab.py - .gitlab/rel_eng/mk-ghcup-metadata/mk_ghcup_metadata.py - .gitlab/test-metrics.sh - compiler/GHC.hs - compiler/GHC/Builtin/Names.hs - compiler/GHC/Builtin/PrimOps.hs - compiler/GHC/Builtin/PrimOps/Ids.hs - compiler/GHC/Builtin/Types/Literals.hs - compiler/GHC/Builtin/Utils.hs - compiler/GHC/ByteCode/Asm.hs - compiler/GHC/ByteCode/Breakpoints.hs - compiler/GHC/ByteCode/InfoTable.hs - compiler/GHC/ByteCode/Instr.hs - compiler/GHC/ByteCode/Linker.hs - compiler/GHC/ByteCode/Types.hs - compiler/GHC/Cmm.hs - compiler/GHC/Cmm/BlockId.hs - 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testsuite/tests/typecheck/should_fail/T22924b.stderr - + testsuite/tests/typecheck/should_fail/T23162b.hs - + testsuite/tests/typecheck/should_fail/T23162b.stderr - + testsuite/tests/typecheck/should_fail/T23162c.hs - + testsuite/tests/typecheck/should_fail/T23162d.hs - testsuite/tests/typecheck/should_fail/T25325.stderr - testsuite/tests/typecheck/should_fail/T5236.stderr - testsuite/tests/typecheck/should_fail/T5246.stderr - testsuite/tests/typecheck/should_fail/T5978.stderr - testsuite/tests/typecheck/should_fail/T9612.stderr - testsuite/tests/typecheck/should_fail/TcCoercibleFail.stderr - testsuite/tests/typecheck/should_fail/all.T - testsuite/tests/typecheck/should_fail/tcfail143.stderr - testsuite/tests/warnings/should_compile/DodgyExports03.stderr - testsuite/tests/warnings/should_compile/DodgyImports.stderr - + testsuite/tests/warnings/should_compile/DodgyImports02.hs - + testsuite/tests/warnings/should_compile/DodgyImports02.stderr - + testsuite/tests/warnings/should_compile/DodgyImports03.hs - + testsuite/tests/warnings/should_compile/DodgyImports03.stderr - + testsuite/tests/warnings/should_compile/DodgyImports03_helper.hs - + testsuite/tests/warnings/should_compile/DodgyImports04.hs - + testsuite/tests/warnings/should_compile/DodgyImports04.stderr - testsuite/tests/warnings/should_compile/DodgyImports_hiding.stderr - testsuite/tests/warnings/should_compile/all.T - utils/check-exact/ExactPrint.hs - utils/deriveConstants/Main.hs - utils/genapply/Main.hs - utils/haddock/haddock-api/haddock-api.cabal - − utils/haddock/haddock-api/src/Haddock/Backends/HaddockDB.hs - utils/haddock/haddock-api/src/Haddock/Convert.hs - utils/haddock/haddock-api/src/Haddock/Interface/Create.hs The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/2e5901d9503f1f9443ef1d4e433d0f… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/2e5901d9503f1f9443ef1d4e433d0f… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc] Pushed new branch wip/T26707
by Teo Camarasu (＠teo) 07 Jan '26

07 Jan '26

Teo Camarasu pushed new branch wip/T26707 at Glasgow Haskell Compiler / GHC -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/tree/wip/T26707 You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][wip/dcoutts/windows-dlls] Try enabling -dynamic-too on Windows
by Duncan Coutts (＠dcoutts) 06 Jan '26

06 Jan '26

Duncan Coutts pushed to branch wip/dcoutts/windows-dlls at Glasgow Haskell Compiler / GHC Commits: ec1fa7ff by Duncan Coutts at 2026-01-06T17:59:07+00:00 Try enabling -dynamic-too on Windows It ought to work, and otherwise we have to teach hadrian how to build without using -dynamic-too. - - - - - 1 changed file: - compiler/GHC/Driver/Session.hs Changes: ===================================== compiler/GHC/Driver/Session.hs ===================================== @@ -3588,7 +3588,7 @@ compilerInfo dflags ("target has RTS linker", showBool $ platformHasRTSLinker platform), ("Target default backend", show $ platformDefaultBackend platform), -- Whether or not we support @-dynamic-too@ - ("Support dynamic-too", showBool $ not isWindows), + ("Support dynamic-too", "YES"), -- Whether or not we support the @-j@ flag with @--make@. ("Support parallel --make", "YES"), -- Whether or not we support "Foo from foo-0.1-XXX:Foo" syntax in @@ -3623,7 +3623,6 @@ compilerInfo dflags showBool True = "YES" showBool False = "NO" platform = targetPlatform dflags - isWindows = platformOS platform == OSMinGW32 expandDirectories = expandToolDir (toolDir dflags) . expandTopDir (topDir dflags) query :: (Target -> a) -> a query f = f (rawTarget dflags) @@ -3712,11 +3711,6 @@ makeDynFlagsConsistent :: DynFlags -> (DynFlags, [Warn], [Located SDoc]) -- ensure that a later change doesn't invalidate an earlier check. -- Be careful not to introduce potential loops! makeDynFlagsConsistent dflags - -- Disable -dynamic-too on Windows (#8228, #7134, #5987) - | os == OSMinGW32 && gopt Opt_BuildDynamicToo dflags - = let dflags' = gopt_unset dflags Opt_BuildDynamicToo - warn = "-dynamic-too is not supported on Windows" - in loop dflags' warn -- Disable -dynamic-too if we are are compiling with -dynamic already, otherwise -- you get two dynamic object files (.o and .dyn_o). (#20436) | ways dflags `hasWay` WayDyn && gopt Opt_BuildDynamicToo dflags View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/ec1fa7ff2018a10b552cfe5333a3399… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/ec1fa7ff2018a10b552cfe5333a3399… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][wip/dcoutts/windows-dlls] Try enabling -dynamic-too on Windows
by Duncan Coutts (＠dcoutts) 06 Jan '26

06 Jan '26

Duncan Coutts pushed to branch wip/dcoutts/windows-dlls at Glasgow Haskell Compiler / GHC Commits: 56d12f83 by Duncan Coutts at 2026-01-06T17:55:31+00:00 Try enabling -dynamic-too on Windows It ought to work, and otherwise we have to teach hadrian how to build without using -dynamic-too. - - - - - 1 changed file: - compiler/GHC/Driver/Session.hs Changes: ===================================== compiler/GHC/Driver/Session.hs ===================================== @@ -3588,7 +3588,7 @@ compilerInfo dflags ("target has RTS linker", showBool $ platformHasRTSLinker platform), ("Target default backend", show $ platformDefaultBackend platform), -- Whether or not we support @-dynamic-too@ - ("Support dynamic-too", showBool $ not isWindows), + ("Support dynamic-too", "YES"), -- Whether or not we support the @-j@ flag with @--make@. ("Support parallel --make", "YES"), -- Whether or not we support "Foo from foo-0.1-XXX:Foo" syntax in @@ -3623,7 +3623,6 @@ compilerInfo dflags showBool True = "YES" showBool False = "NO" platform = targetPlatform dflags - isWindows = platformOS platform == OSMinGW32 expandDirectories = expandToolDir (toolDir dflags) . expandTopDir (topDir dflags) query :: (Target -> a) -> a query f = f (rawTarget dflags) View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/56d12f83a4cbebac68fc8b8cb30cdd3… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/56d12f83a4cbebac68fc8b8cb30cdd3… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][wip/spj-try-opt-coercion] 3 commits: Drastically reduce the use of the coercion optimiser
by Simon Peyton Jones (＠simonpj) 06 Jan '26

06 Jan '26

Simon Peyton Jones pushed to branch wip/spj-try-opt-coercion at Glasgow Haskell Compiler / GHC Commits: 46af7510 by Simon Peyton Jones at 2026-01-06T16:09:19+00:00 Drastically reduce the use of the coercion optimiser This MR addresess #26679 by calling the coercion optimiser much less often; the coercion optimiser is expensive, and often ineffective, especially when it is called repeatedly. See Note [Coercion optimisation] in GHC.Core.Corecion.Opt. Specifically * Make coercion optimisation into its own pass, controlled by its own flag `-fopt-coercion` like any other pass. The pass runs early in the pipeline. * The Simplifier now contents itself with merely applying the current substitution to a coercion, and checking for reflexivity. * Kill off OptCoercionOpts, which is now unused. Another important, but only loosely related, improvement * In `GHC.Core.Subst.substIdBndr`, `GHC.Core.TyCo.Subst.substTyVarBndrUsing`, and `GHC.Core.TyCo.Subst.substTyVarBndrUsing`, check for an empty substitution. This keeps substitutions empty in the no-op case. See Note [Keeping the substitution empty] in GHC.Core.TyCo.Subst Compile time improves. Here are the compile-time allocation change over 1%: Baseline Test value Change ------------------------------------------------------------ CoOpt_Singletons(normal) 721,677,974 -7.9% GOOD LargeRecord(normal) 1,268,094,410 -20.4% GOOD T12545(normal) 772,150,124 -9.2% T12707(normal) 777,720,918 -1.5% GOOD T14766(normal) 918,228,179 -50.2% GOOD T15703(normal) 318,141,541 +1.0% BAD T18223(normal) 371,496,473 -7.6% GOOD T1969(normal) 670,830,326 +2.2% BAD T20261(normal) 573,444,953 -2.2% T24984(normal) 87,836,660 -1.5% T3064(normal) 171,636,592 -6.2% GOOD T5030(normal) 148,301,062 -16.4% GOOD T5321Fun(normal) 263,120,022 -3.3% GOOD T8095(normal) 777,033,006 -71.3% GOOD T9020(optasm) 222,159,574 -2.5% GOOD T9630(normal) 873,422,584 -15.4% GOOD T9872b(normal) 1,906,890,318 -2.9% GOOD T9872b_defer(normal) 2,878,170,737 -2.1% GOOD T9872d(normal) 356,978,798 -7.7% GOOD TcPlugin_RewritePerf(normal) 2,132,138,060 -2.6% GOOD geo. mean -2.7% minimum -71.3% maximum +2.2% Metric Decrease: CoOpt_Singletons LargeRecord T12707 T14766 T18223 T3064 T5030 T5321Fun T8095 T9020 T9630 T9872b T9872b_defer T9872d TcPlugin_RewritePerf Metric Increase: T15703 T1969 - - - - - ceeeb350 by Simon Peyton Jones at 2026-01-06T16:10:06+00:00 Try harder to keep the substitution empty See Note [Keeping the substitution empty] - - - - - 528c804f by Simon Peyton Jones at 2026-01-06T16:10:38+00:00 Serious attempt to avoid duplicating large coercions Wibbles Progress on not-inlining coercions Add a type signature More on exported coercions More on coercion bindings Allow in letrec; indeed make the invariants for letrec the same as the invariants for top-level bindings. ToDo: document this - - - - - 37 changed files: - compiler/GHC/Core/Coercion.hs - compiler/GHC/Core/Coercion/Opt.hs - compiler/GHC/Core/FVs.hs - compiler/GHC/Core/Lint.hs - compiler/GHC/Core/Opt/Pipeline.hs - compiler/GHC/Core/Opt/Pipeline/Types.hs - compiler/GHC/Core/Opt/Simplify/Env.hs - compiler/GHC/Core/Opt/Simplify/Iteration.hs - compiler/GHC/Core/Opt/Simplify/Utils.hs - compiler/GHC/Core/Ppr.hs - compiler/GHC/Core/Rules.hs - compiler/GHC/Core/SimpleOpt.hs - compiler/GHC/Core/Subst.hs - compiler/GHC/Core/TyCo/FVs.hs - compiler/GHC/Core/TyCo/Rep.hs - compiler/GHC/Core/TyCo/Subst.hs - compiler/GHC/Core/Utils.hs - compiler/GHC/CoreToIface.hs - compiler/GHC/CoreToStg.hs - compiler/GHC/CoreToStg/Prep.hs - compiler/GHC/Driver/Config.hs - compiler/GHC/Driver/Config/Core/Lint.hs - compiler/GHC/Driver/Config/Core/Opt/Simplify.hs - compiler/GHC/Driver/DynFlags.hs - compiler/GHC/Driver/Flags.hs - compiler/GHC/Driver/Session.hs - compiler/GHC/Iface/Rename.hs - compiler/GHC/Iface/Syntax.hs - compiler/GHC/Iface/Tidy.hs - compiler/GHC/Iface/Type.hs - compiler/GHC/IfaceToCore.hs - compiler/GHC/Types/Var/Env.hs - docs/users_guide/using-optimisation.rst - hadrian/src/Flavour.hs - testsuite/tests/count-deps/CountDepsAst.stdout - testsuite/tests/count-deps/CountDepsParser.stdout - testsuite/tests/simplCore/should_compile/T8331.stderr The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/5c1b0929866b379080e3f33a2aed44… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/5c1b0929866b379080e3f33a2aed44… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][wip/dcoutts/windows-dlls] 2 commits: Enable dynamic lib support on Windows
by Duncan Coutts (＠dcoutts) 06 Jan '26

06 Jan '26

Duncan Coutts pushed to branch wip/dcoutts/windows-dlls at Glasgow Haskell Compiler / GHC Commits: 863db4f4 by Duncan Coutts at 2026-01-06T17:42:12+00:00 Enable dynamic lib support on Windows This does not mean it works, it means the build system will now try to build dynamic libs. We'll find out what breaks! - - - - - c4f9fe0c by Duncan Coutts at 2026-01-06T17:43:28+00:00 Hadrian: remove legacy rts .so symlinks For compatibility with the old makefile based build system, hadrian had rules to generate symlinks from unversioned to versioned names for the rts .so/.dynlib file, like libHSrts-ghcx.y.so -> libHSrts-1.0.3-ghcx.y.so We no longer need these symlinks since the makefile build system has been retired some time ago. The need for these symlinks is awkward on windows where we cannot (in practice) create symlinks. So rather than make them conditional (non-windows), just remove them entirely. - - - - - 3 changed files: - hadrian/src/Oracles/Flag.hs - hadrian/src/Rules/Register.hs - hadrian/src/Rules/Rts.hs Changes: ===================================== hadrian/src/Oracles/Flag.hs ===================================== @@ -92,11 +92,10 @@ arSupportsAtFile stage = Toolchain.arSupportsAtFile . tgtAr <$> targetStage stag platformSupportsSharedLibs :: Action Bool -- FIXME: This is querying about the target but is named "platformXXX", targetSupportsSharedLibs would be better platformSupportsSharedLibs = do - windows <- isWinTarget ppc_linux <- (&&) <$> anyTargetArch [ ArchPPC ] <*> anyTargetOs [ OSLinux ] solaris <- (&&) <$> anyTargetArch [ ArchX86 ] <*> anyTargetOs [ OSSolaris2 ] javascript <- anyTargetArch [ ArchJavaScript ] - return $ not (windows || javascript || ppc_linux || solaris) + return $ not (javascript || ppc_linux || solaris) -- | Does the target support threaded RTS? targetSupportsThreadedRts :: Action Bool ===================================== hadrian/src/Rules/Register.hs ===================================== @@ -14,7 +14,6 @@ import Hadrian.Expression import Hadrian.Haskell.Cabal import Oracles.Flag (platformSupportsGhciObjects) import Packages -import Rules.Rts import Settings import Target import Utilities @@ -91,14 +90,9 @@ parseToBuildSubdirectory root = do -- * Registering registerPackages :: [Context] -> Action () -registerPackages ctxs = do +registerPackages ctxs = need =<< mapM pkgRegisteredLibraryFile ctxs - -- Dynamic RTS library files need symlinks (Rules.Rts.rtsRules). - forM_ ctxs $ \ ctx -> when (package ctx == rts) $ do - ways <- interpretInContext ctx (getLibraryWays <> getRtsWays) - needRtsSymLinks (stage ctx) ways - -- | Register a package and initialise the corresponding package database if -- need be. Note that we only register packages in 'Stage0' and 'Stage1'. registerPackageRules :: [(Resource, Int)] -> Stage -> Inplace -> Rules () ===================================== hadrian/src/Rules/Rts.hs ===================================== @@ -1,10 +1,5 @@ -{-# LANGUAGE MultiWayIf #-} +module Rules.Rts (rtsRules) where -module Rules.Rts (rtsRules, needRtsSymLinks) where - -import qualified Data.Set as Set - -import Packages (rts) import Hadrian.Utilities import Settings.Builders.Common @@ -12,17 +7,7 @@ import Settings.Builders.Common -- library files (see Rules.Library.libraryRules). rtsRules :: Rules () rtsRules = priority 3 $ do - -- Dynamic RTS library files need symlinks without the dummy version number. - -- This is for backwards compatibility (the old make build system omitted the - -- dummy version number). root <- buildRootRules - [ root -/- "**/libHSrts_*-ghc*.so", - root -/- "**/libHSrts_*-ghc*.dylib", - root -/- "**/libHSrts-ghc*.so", - root -/- "**/libHSrts-ghc*.dylib"] - |%> \ rtsLibFilePath' -> createFileLink - (addRtsDummyVersion $ takeFileName rtsLibFilePath') - rtsLibFilePath' -- An import lib for the ghc-internal dll, to be linked into the rts dll. forM_ [Stage1, Stage2, Stage3] $ \stage -> do let buildPath = root -/- buildDir (rtsContext stage) @@ -36,35 +21,3 @@ buildGhcInternalImportLib target = do output = target -- the .dll.a import lib need [input] runBuilder Dlltool ["-d", input, "-l", output] [input] [output] - --- Need symlinks generated by rtsRules. -needRtsSymLinks :: Stage -> Set.Set Way -> Action () -needRtsSymLinks stage rtsWays - = forM_ (Set.filter (wayUnit Dynamic) rtsWays) $ \ way -> do - let ctx = Context stage rts way Final - distDir <- distDynDir ctx - rtsLibFile <- takeFileName <$> pkgLibraryFile ctx - need [removeRtsDummyVersion (distDir </> rtsLibFile)] - -prefix, versionlessPrefix :: String -versionlessPrefix = "libHSrts" -prefix = versionlessPrefix ++ "-1.0.3" - --- removeRtsDummyVersion "a/libHSrts-1.0-ghc1.2.3.4.so" --- == "a/libHSrts-ghc1.2.3.4.so" -removeRtsDummyVersion :: FilePath -> FilePath -removeRtsDummyVersion = replaceLibFilePrefix prefix versionlessPrefix - --- addRtsDummyVersion "a/libHSrts-ghc1.2.3.4.so" --- == "a/libHSrts-1.0-ghc1.2.3.4.so" -addRtsDummyVersion :: FilePath -> FilePath -addRtsDummyVersion = replaceLibFilePrefix versionlessPrefix prefix - -replaceLibFilePrefix :: String -> String -> FilePath -> FilePath -replaceLibFilePrefix oldPrefix newPrefix oldFilePath = let - oldFileName = takeFileName oldFilePath - newFileName = maybe - (error $ "Expected RTS library file to start with " ++ oldPrefix) - (newPrefix ++) - (stripPrefix oldPrefix oldFileName) - in replaceFileName oldFilePath newFileName View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/ee48ae75770fc42fa37bf341e8ad1f… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/ee48ae75770fc42fa37bf341e8ad1f… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][wip/T26722] Add evals for strict data-con args in worker-functions
by Simon Peyton Jones (＠simonpj) 06 Jan '26

06 Jan '26

Simon Peyton Jones pushed to branch wip/T26722 at Glasgow Haskell Compiler / GHC Commits: ee290e4b by Simon Peyton Jones at 2026-01-06T17:41:33+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] - - - - - 10 changed files: - compiler/GHC/Core/Opt/SpecConstr.hs - compiler/GHC/Core/Tidy.hs - compiler/GHC/Core/Utils.hs - compiler/GHC/Stg/EnforceEpt.hs - compiler/GHC/StgToCmm/Closure.hs - compiler/GHC/StgToCmm/Expr.hs - hadrian/src/Flavour.hs - + testsuite/tests/simplCore/should_compile/T26722.hs - + testsuite/tests/simplCore/should_compile/T26722.stderr - testsuite/tests/simplCore/should_compile/all.T Changes: ===================================== compiler/GHC/Core/Opt/SpecConstr.hs ===================================== @@ -2062,7 +2062,7 @@ mkSeqs seqees res_ty rhs = addEval :: Var -> CoreExpr -> CoreExpr addEval arg_id rhs -- Argument representing strict field and it's worth passing via cbv - | shouldStrictifyIdForCbv arg_id + | wantCbvForId arg_id = Case (Var arg_id) (localiseId arg_id) -- See (SCF1) in Note [SpecConstr and strict fields] res_ty ===================================== compiler/GHC/Core/Tidy.hs ===================================== @@ -38,7 +38,7 @@ import GHC.Utils.Outputable import GHC.Types.RepType (typePrimRep) import GHC.Utils.Panic import GHC.Types.Basic (isMarkedCbv, CbvMark (..)) -import GHC.Core.Utils (shouldUseCbvForId) +import GHC.Core.Utils ( wantCbvForId ) {- ************************************************************************ @@ -197,7 +197,7 @@ computeCbvInfo fun_id rhs isSimplePrimRep _ = False mkMark arg - | not $ shouldUseCbvForId arg = NotMarkedCbv + | not $ wantCbvForId arg = NotMarkedCbv -- We can only safely use cbv for strict arguments | (isStrUsedDmd (idDemandInfo arg)) , not (isDeadEndId fun_id) = MarkedCbv ===================================== compiler/GHC/Core/Utils.hs ===================================== @@ -58,7 +58,7 @@ module GHC.Core.Utils ( isJoinBind, -- * Tag inference - mkStrictFieldSeqs, shouldStrictifyIdForCbv, shouldUseCbvForId, + mkStrictFieldSeqs, wantCbvForId, -- * unsafeEqualityProof isUnsafeEqualityCase, @@ -2902,18 +2902,24 @@ Here comes the tricky part: If we make $wloop strict in both x/y and we get: }; end Rec } -Here both x and y are known to be tagged in the function body since we pass strict worker args using unlifted cbv. -This means the seqs on x and y both become no-ops and compared to the first version the seq on `y` disappears at runtime. - -The downside is that the caller of $wfoo potentially has to evaluate `y` once if we can't prove it isn't already evaluated. -But y coming out of a strict field is in WHNF so safe to evaluated. And most of the time it will be properly tagged+evaluated -already at the call site because of the EPT Invariant! See Note [EPT enforcement] for more in this. -This makes GHC itself around 1% faster despite doing slightly more work! So this is generally quite good. - -We only apply this when we think there is a benefit in doing so however. There are a number of cases in which -it would be useless to insert an extra seq. ShouldStrictifyIdForCbv tries to identify these to avoid churn in the +Here both x and y are known to be tagged in the function body since we pass +strict worker args using unlifted cbv. This means the seqs on x and y both +become no-ops (via (EPT-codegen) in Not [EPT enforcement]) and, compared to the +first version, the seq on `y` disappears at runtime. + +The downside is that the caller of $wfoo potentially has to evaluate `y` once if +we can't prove it isn't already evaluated. But y coming out of a strict field +is in WHNF so safe to evaluated. And most of the time it will be properly +tagged+evaluated already at the call site because of the EPT Invariant! See Note +[EPT enforcement] for more in this. This makes GHC itself around 1% faster +despite doing slightly more work! So this is generally quite good. + +We only apply this when we think there is a benefit in doing so however. There +are a number of cases in which it would be useless to insert an extra +seq. `wantCbvForId` tries to identify these to avoid churn in the simplifier. See Note [Which Ids should be strictified] for details on this. -} + mkStrictFieldSeqs :: [(Id,StrictnessMark)] -> CoreExpr -> (CoreExpr) mkStrictFieldSeqs args rhs = foldr addEval rhs args @@ -2923,7 +2929,7 @@ mkStrictFieldSeqs args rhs = addEval (arg_id,arg_cbv) (rhs) -- Argument representing strict field. | isMarkedStrict arg_cbv - , shouldStrictifyIdForCbv arg_id + , wantCbvForId arg_id -- Make sure to remove unfoldings here to avoid the simplifier dropping those for OtherCon[] unfoldings. = Case (Var $! zapIdUnfolding arg_id) arg_id case_ty ([Alt DEFAULT [] rhs]) -- Normal argument @@ -2943,87 +2949,99 @@ There are multiple reasons why we might not want to insert a seq in the rhs to strictify a functions argument: 1) The argument doesn't exist at runtime. - -For zero width types (like Types) there is no benefit as we don't operate on them -at runtime at all. This includes things like void#, coercions and state tokens. + For zero width types (like Types) there is no benefit as we don't operate on them + at runtime at all. This includes things like void#, coercions and state tokens. 2) The argument is a unlifted type. - -If the argument is a unlifted type the calling convention already is explicitly -cbv. This means inserting a seq on this argument wouldn't do anything as the seq -would be a no-op *and* it wouldn't affect the calling convention. + If the argument is a unlifted type the calling convention already is explicitly + cbv. This means inserting a seq on this argument wouldn't do anything as the seq + would be a no-op *and* it wouldn't affect the calling convention. 3) The argument is absent. + If the argument is absent in the body there is no advantage to it being passed as + cbv to the function. The function won't ever look at it so we don't save any work. -If the argument is absent in the body there is no advantage to it being passed as -cbv to the function. The function won't ever look at it so we don't safe any work. - -This mostly happens for join point. For example we might have: - - data T = MkT ![Int] [Char] - f t = case t of MkT xs{strict} ys-> snd (xs,ys) - -and abstract the case alternative to: + This mostly happens for join points. For example we might have: - f t = join j1 = \xs ys -> snd (xs,ys) - in case t of MkT xs{strict} ys-> j1 xs xy + data T = MkT ![Int] [Char] + f t = case t of MkT xs{strict} ys-> snd (xs,ys) -While we "use" xs inside `j1` it's not used inside the function `snd` we pass it to. -In short a absent demand means neither our RHS, nor any function we pass the argument -to will inspect it. So there is no work to be saved by forcing `xs` early. + and abstract the case alternative to: -NB: There is an edge case where if we rebox we *can* end up seqing an absent value. -Note [Absent fillers] has an example of this. However this is so rare it's not worth -caring about here. + f t = join j1 = \xs ys -> snd (xs,ys) + in case t of MkT xs{strict} ys-> j1 xs xy -4) The argument is already strict. + While we "use" xs inside `j1` it's not used inside the function `snd` we pass it to. + In short a absent demand means neither our RHS, nor any function we pass the argument + to will inspect it. So there is no work to be saved by forcing `xs` early. -Consider this code: - - data T = MkT ![Int] - f t = case t of MkT xs{strict} -> reverse xs - -The `xs{strict}` indicates that `xs` is used strictly by the `reverse xs`. -If we do a w/w split, and add the extra eval on `xs`, we'll get - - $wf xs = - case xs of xs1 -> - let t = MkT xs1 in - case t of MkT xs2 -> reverse xs2 - -That's not wrong; but the w/w body will simplify to - - $wf xs = case xs of xs1 -> reverse xs1 - -and now we'll drop the `case xs` because `xs1` is used strictly in its scope. -Adding that eval was a waste of time. So don't add it for strictly-demanded Ids. + NB: There is an edge case where if we rebox we *can* end up seqing an absent value. + Note [Absent fillers] has an example of this. However this is so rare it's not worth + caring about here. 5) Functions - -Functions are tricky (see Note [TagInfo of functions] in EnforceEpt). -But the gist of it even if we make a higher order function argument strict -we can't avoid the tag check when it's used later in the body. -So there is no benefit. + Functions are tricky (see Note [TagInfo of functions] in EnforceEpt). + But the gist of it even if we make a higher order function argument strict + we can't avoid the tag check when it's used later in the body. + So there is no benefit. + +Wrinkles: + +(WIS1) You might have thought that we can omit the eval if the argument is used + strictly demanded in the body. But you'd be wrong. Consider this code: + data T = MkT ![Int] + f t = case t of MkT xs{Dmd=STR} -> reverse xs + + The `xs{Dmd=STR}` indicates that `xs` is used strictly by the `reverse xs`. + If we do a w/w split, and add the extra eval on `xs`, we'll get + $wf xs = case xs of xs1 -> + let t = MkT xs1 in + case t of MkT xs2 -> reverse xs2 + + That's not wrong; but you might wonder if the eval on `xs` is needed + when it is certainly evaluated by the `reverse`. But yes, it is (#26722): + g s True t = f s t t + g s False t = g s True t + + f True (MkT xs) t = f False (MkT xs) t + f False (MkT xs) _ = xs + + After worker/wrapper we get: + g s b t = case t of MkT ww -> $wg s b ww + $wg s ds ww = case ds of { + False -> case ww of wg { __DEFAULT -> Bar.$wg s True wg } + True -> let { t1 = MkT ww } in f s t1 t1 } + + We must make `f` inline inside `$wg`, because `f` too is ww'd, and we + don't want to rebox `t1` before passing it to `f`. BUT while `t1` + looks like a HNF, `exprIsHNF` will say False because `MkT` is strict + and `ww` isn't evaluated. So `f` doesn't inline and we get lots of + reboxing. + + The Right Thing to to is to add the eval for the data con argument: + $wg s ds ww = case ww of ww' { DEFAULT -> + case ds of { + False -> case ww of wg { __DEFAULT -> Bar.$wg s True wg } + True -> let { t1 = MkT ww' } in f s t1 t1 } } + + Now `t1` will be a HNF, and `f` will inline, and we get + $wg s ds ww = case ww of ww' { DEFAULT -> + case ds of { + False -> Bar.$wg s True ww' + True -> $wf s ww' + + (Ultimately `$wg` will be a CBV function, so that `case ww` will be a + no-op: see (EPT-codegen) in Note [EPT enforcement] in GHC.Stg.EnforceEpt.) -} --- | Do we expect there to be any benefit if we make this var strict --- in order for it to get treated as as cbv argument? --- See Note [Which Ids should be strictified] --- See Note [CBV Function Ids] for more background. -shouldStrictifyIdForCbv :: Var -> Bool -shouldStrictifyIdForCbv = wantCbvForId False - --- Like shouldStrictifyIdForCbv but also wants to use cbv for strict args. -shouldUseCbvForId :: Var -> Bool -shouldUseCbvForId = wantCbvForId True -- When we strictify we want to skip strict args otherwise the logic is the same --- as for shouldUseCbvForId so we common up the logic here. +-- as for wantCbvForId so we common up the logic here. -- Basically returns true if it would be beneficial for runtime to pass this argument -- as CBV independent of weither or not it's correct. E.g. it might return true for lazy args -- we are not allowed to force. -wantCbvForId :: Bool -> Var -> Bool -wantCbvForId cbv_for_strict v +wantCbvForId :: Var -> Bool +wantCbvForId v -- Must be a runtime var. -- See Note [Which Ids should be strictified] point 1) | isId v @@ -3037,9 +3055,6 @@ wantCbvForId cbv_for_strict v , not $ isFunTy ty -- If the var is strict already a seq is redundant. -- See Note [Which Ids should be strictified] point 4) - , not (isStrictDmd dmd) || cbv_for_strict - -- If the var is absent a seq is almost always useless. - -- See Note [Which Ids should be strictified] point 3) , not (isAbsDmd dmd) = True | otherwise ===================================== compiler/GHC/Stg/EnforceEpt.hs ===================================== @@ -140,9 +140,11 @@ Afterwards, the *EPT rewriter* inserts the actual evals realising Upcasts. Implementation -------------- -* EPT analysis is implemented in GHC.Stg.EnforceEpt.inferTags. +(EPT-anal) EPT analysis is implemented in `GHC.Stg.EnforceEpt.inferTags.` It attaches its result to /binders/, not occurrence sites. -* The EPT rewriter establishes the EPT invariant by inserting evals. That is, if + +(EPT-rewrite) The EPT rewriter, `GHC.Stg.EnforceEpt.Rewrite.rewriteTopBinds`, + establishes the EPT invariant by inserting evals. That is, if (a) a binder x is used to * construct a strict field (`SP x y`), or * passed as a CBV argument (`$wf x`), @@ -152,17 +154,27 @@ Implementation case x of x' { __ DEFAULT -> SP x' y }. case x of x' { __ DEFAULT -> $wf x' }. (Recall that the case binder x' is always EPT.) - This is implemented in GHC.Stg.EnforceEpt.Rewrite.rewriteTopBinds. + This pass also propagates the EPTness from binders to occurrences. + It is sound to insert evals on strict fields (Note [Strict fields in Core]), and on CBV arguments as well (Note [CBV Function Ids]). -* We also export the EPTness of top level bindings to allow this optimisation + +(EPT-codegen) Finally, code generation for (case x of alts) skips the thunk check + when `x` is EPT. This is done (a bit indirectly) thus: + * GHC.StgToCmm.Expr.cgCase: builds a `sequel`, and recurses into `cgExpr` on `x`. + * When `cgExpr` sees a `x` goes to `cgIdApp`, which uses `getCallMethod`. + * Then `getCallMethod` sees that `x` is EPT (via `idTagSigMaybe`), and + returns `InferredReturnIt`. + * Now `cgIdApp` can jump straight to the case-alternative switch in the `sequel` + constructed by `cgCase`. + +(EPT-export) We also export the EPTness of top level bindings to allow this optimisation to work across module boundaries. + NB: The EPT Invariant *must* be upheld, regardless of the optimisation level; hence EPTness is practically part of the internal ABI of a strict data constructor or CBV function. Note [CBV Function Ids] contains the details. -* Finally, code generation skips the thunk check when branching on binders that - are EPT. This is done by `cgExpr`/`cgCase` in the backend. Evaluation ---------- ===================================== compiler/GHC/StgToCmm/Closure.hs ===================================== @@ -617,12 +617,15 @@ getCallMethod cfg name id (LFThunk _ _ updatable std_form_info is_fun) getCallMethod cfg name id (LFUnknown might_be_a_function) n_args _cg_locs _self_loop_info | n_args == 0 , Just sig <- idTagSig_maybe id - , isTaggedSig sig -- Infered to be already evaluated by EPT analysis - -- When profiling we must enter all potential functions to make sure we update the SCC - -- even if the function itself is already evaluated. + , isTaggedSig sig -- This `id` is evaluated and properly tagged; no need to enter it + -- See (EPT-codegen) in Note [EPT enforcement] in GHC.Stg.EnforceEpt + + -- When profiling we must enter all potential functions to make sure we update + -- the SCC even if the function itself is already evaluated. -- See Note [Evaluating functions with profiling] in rts/Apply.cmm , not (profileIsProfiling (stgToCmmProfile cfg) && might_be_a_function) - = InferedReturnIt -- See Note [EPT enforcement] + + = InferedReturnIt -- See (EPT-codegen) in Note [EPT enforcement] | might_be_a_function = SlowCall ===================================== compiler/GHC/StgToCmm/Expr.hs ===================================== @@ -1053,6 +1053,7 @@ cgIdApp fun_id args = do | otherwise -> emitReturn [fun] -- A value infered to be in WHNF, so we can just return it. + -- See (EPT-codegen) in Note [EPT enforcement] in GHC.Stg.EnforceEpt InferedReturnIt | isZeroBitTy (idType fun_id) -> trace >> emitReturn [] | otherwise -> trace >> assertTag >> ===================================== hadrian/src/Flavour.hs ===================================== @@ -70,7 +70,8 @@ flavourTransformers = M.fromList , "fully_static" =: fullyStatic , "host_fully_static" =: hostFullyStatic , "collect_timings" =: collectTimings - , "assertions" =: enableAssertions + , "assertions" =: enableAssertions Stage2 + , "assertions_stage1" =: enableAssertions Stage1 , "debug_ghc" =: debugGhc Stage2 , "debug_stage1_ghc" =: debugGhc Stage1 , "lint" =: enableLinting @@ -394,11 +395,11 @@ enableLateCCS = addArgs ? arg "-fprof-late" -- | Enable assertions for the stage2 compiler -enableAssertions :: Flavour -> Flavour -enableAssertions flav = flav { ghcDebugAssertions = f } +enableAssertions :: Stage -> Flavour -> Flavour +enableAssertions stage flav = flav { ghcDebugAssertions = f } where - f Stage2 = True - f st = ghcDebugAssertions flav st + f s | s == stage = True + | otherwise = ghcDebugAssertions flav s -- | Build the stage3 compiler using the non-moving GC. enableBootNonmovingGc :: Flavour -> Flavour ===================================== testsuite/tests/simplCore/should_compile/T26722.hs ===================================== @@ -0,0 +1,9 @@ +module T26722 where + +data T = MkT ![Int] + +g s True t = f s t t +g s False t = g s True t + +f True (MkT xs) t = f False (MkT xs) t +f False (MkT xs) _ = xs ===================================== testsuite/tests/simplCore/should_compile/T26722.stderr ===================================== @@ -0,0 +1 @@ + \ No newline at end of file ===================================== testsuite/tests/simplCore/should_compile/all.T ===================================== @@ -563,3 +563,6 @@ test('T26115', [grep_errmsg(r'DFun')], compile, ['-O -ddump-simpl -dsuppress-uni test('T26116', normal, compile, ['-O -ddump-rules']) test('T26117', [grep_errmsg(r'==')], compile, ['-O -ddump-simpl -dsuppress-uniques']) test('T26349', normal, compile, ['-O -ddump-rules']) + +# T26722: there should be no reboxing in $wg +test('T26722', [grep_errmsg(r'SPEC')], compile, ['-O -dno-typeable-binds']) View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/ee290e4bfc327e60346f927f618cce4… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/ee290e4bfc327e60346f927f618cce4… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc] Pushed new branch wip/T26722
by Simon Peyton Jones (＠simonpj) 06 Jan '26

06 Jan '26

Simon Peyton Jones pushed new branch wip/T26722 at Glasgow Haskell Compiler / GHC -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/tree/wip/T26722 You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][wip/fix-clang64-split-sections] 9 commits: Improved fundeps for closed type families
by Cheng Shao (＠TerrorJack) 06 Jan '26

06 Jan '26

Cheng Shao pushed to branch wip/fix-clang64-split-sections at Glasgow Haskell Compiler / GHC Commits: 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 - - - - - 76b190c5 by Cheng Shao at 2026-01-06T17:30:21+01:00 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. - - - - - b5c1becd by Cheng Shao at 2026-01-06T17:30:21+01:00 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. - - - - - b70bcb0e by Cheng Shao at 2026-01-06T17:30:32+01:00 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: T9675 size_hello_artifact size_hello_artifact_gzip size_hello_unicode size_hello_unicode_gzip Metric Increase: T13035 ------------------------- Co-authored-by: Codex <codex(a)openai.com> - - - - - 78 changed files: - compiler/GHC/Cmm.hs - compiler/GHC/Cmm/InitFini.hs - compiler/GHC/CmmToAsm/AArch64/Ppr.hs - compiler/GHC/CmmToAsm/Ppr.hs - compiler/GHC/CmmToAsm/Wasm/FromCmm.hs - compiler/GHC/CmmToAsm/X86/Ppr.hs - compiler/GHC/CmmToC.hs - compiler/GHC/CmmToLlvm/Data.hs - compiler/GHC/Core/FamInstEnv.hs - compiler/GHC/Core/TyCo/Subst.hs - compiler/GHC/Core/TyCon.hs - compiler/GHC/Core/Unify.hs - compiler/GHC/HsToCore/Monad.hs - compiler/GHC/Tc/Errors.hs - compiler/GHC/Tc/Errors/Ppr.hs - compiler/GHC/Tc/Errors/Types.hs - compiler/GHC/Tc/Gen/Splice.hs - compiler/GHC/Tc/Solver.hs - compiler/GHC/Tc/Solver/Default.hs - compiler/GHC/Tc/Solver/Dict.hs - compiler/GHC/Tc/Solver/Equality.hs - compiler/GHC/Tc/Solver/FunDeps.hs - compiler/GHC/Tc/Solver/InertSet.hs - compiler/GHC/Tc/Solver/Monad.hs - compiler/GHC/Tc/Solver/Rewrite.hs - compiler/GHC/Tc/Types/Constraint.hs - compiler/GHC/Tc/Types/CtLoc.hs - compiler/GHC/Tc/Utils/Monad.hs - compiler/GHC/Tc/Utils/Unify.hs - compiler/GHC/Types/TyThing.hs - docs/users_guide/9.16.1-notes.rst - libraries/base/changelog.md - linters/lint-codes/LintCodes/Static.hs - testsuite/tests/indexed-types/should_compile/CEqCanOccursCheck.hs - testsuite/tests/indexed-types/should_fail/T12522a.hs - testsuite/tests/indexed-types/should_fail/T26176.stderr - testsuite/tests/parser/should_fail/RecordDotSyntaxFail10.stderr - testsuite/tests/parser/should_fail/RecordDotSyntaxFail13.stderr - testsuite/tests/parser/should_fail/T20654a.stderr - testsuite/tests/pmcheck/should_compile/T15753c.hs - + testsuite/tests/pmcheck/should_compile/T15753c.stderr - testsuite/tests/pmcheck/should_compile/T15753d.hs - + testsuite/tests/pmcheck/should_compile/T15753d.stderr - + testsuite/tests/pmcheck/should_compile/T22652.hs - + testsuite/tests/pmcheck/should_compile/T22652a.hs - testsuite/tests/pmcheck/should_compile/all.T - + testsuite/tests/polykinds/T13882.hs - testsuite/tests/polykinds/all.T - testsuite/tests/quantified-constraints/T15316A.stderr - testsuite/tests/quantified-constraints/T17267.stderr - testsuite/tests/quantified-constraints/T17267a.stderr - testsuite/tests/quantified-constraints/T17267b.stderr - testsuite/tests/quantified-constraints/T17267c.stderr - testsuite/tests/quantified-constraints/T17267e.stderr - testsuite/tests/quantified-constraints/T17458.stderr - testsuite/tests/typecheck/should_compile/T16188.hs - testsuite/tests/typecheck/should_fail/ContextStack1.stderr - testsuite/tests/typecheck/should_fail/FD3.stderr - testsuite/tests/typecheck/should_fail/FDsFromGivens2.stderr - testsuite/tests/typecheck/should_fail/FunDepOrigin1b.stderr - testsuite/tests/typecheck/should_fail/T13506.stderr - testsuite/tests/typecheck/should_fail/T15767.stderr - testsuite/tests/typecheck/should_fail/T19415.stderr - testsuite/tests/typecheck/should_fail/T19415b.stderr - testsuite/tests/typecheck/should_fail/T22924b.stderr - + testsuite/tests/typecheck/should_fail/T23162b.hs - + testsuite/tests/typecheck/should_fail/T23162b.stderr - + testsuite/tests/typecheck/should_fail/T23162c.hs - + testsuite/tests/typecheck/should_fail/T23162d.hs - testsuite/tests/typecheck/should_fail/T25325.stderr - testsuite/tests/typecheck/should_fail/T5236.stderr - testsuite/tests/typecheck/should_fail/T5246.stderr - testsuite/tests/typecheck/should_fail/T5978.stderr - testsuite/tests/typecheck/should_fail/T9612.stderr - testsuite/tests/typecheck/should_fail/TcCoercibleFail.stderr - testsuite/tests/typecheck/should_fail/all.T - testsuite/tests/typecheck/should_fail/tcfail143.stderr - utils/haddock/haddock-api/src/Haddock/Convert.hs The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/17030d83bcd6a9f9b7e1d758b5efea… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/17030d83bcd6a9f9b7e1d758b5efea… You're receiving this email because of your account on gitlab.haskell.org.

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