- ghc-commits - Haskell.org

[Git][ghc/ghc][wip/validate-fix-werror] 4 commits: rts: fix -Wcompare-distinct-pointer-types errors
by Cheng Shao (＠TerrorJack) 21 Mar '26

21 Mar '26

Cheng Shao pushed to branch wip/validate-fix-werror at Glasgow Haskell Compiler / GHC Commits: 048060c4 by Cheng Shao at 2026-03-20T20:52:19+00:00 rts: fix -Wcompare-distinct-pointer-types errors This commit fixes `-Wcompare-distinct-pointer-types` errors in the RTS which should have been caught by the `validate` flavour but was warnings in CI due to the recent `+werror` regression. - - - - - ef04d07a by Cheng Shao at 2026-03-20T21:09:02+00:00 ghc-internal: fix unused imports This commit fixes unused imports in `ghc-internal` which should have been caught by the `validate` flavour but was warnings in CI due to the recent `+werror` regression. Fixes #26987 #27059. - - - - - 0d4f6077 by Cheng Shao at 2026-03-20T21:09:11+00:00 compiler: fix unused imports in GHC.Tc.Types.Origin This commit fixes unused imports in `GHC.Tc.Types.Origin` which should have been caught by the `validate` flavour but was warnings in CI due to the recent `+werror` regression. Fixes #27059. - - - - - 0fe373a8 by Cheng Shao at 2026-03-20T21:09:11+00:00 hadrian: fix missing +werror in validate flavour This patch fixes missing `+werror` in validate flavour, which was an oversight in bb3a2ba1eefadf0b2ef4f39b31337a23eec67f29. Fixes #27066. - - - - - 12 changed files: - compiler/GHC/Tc/Types/Origin.hs - hadrian/src/Settings/Flavours/Validate.hs - libraries/ghc-internal/src/GHC/Internal/Conc/IO.hs - libraries/ghc-internal/src/GHC/Internal/Event/Control.hs - libraries/ghc-internal/src/GHC/Internal/Float.hs - libraries/ghc-internal/src/GHC/Internal/Float/RealFracMethods.hs - libraries/ghc-internal/src/GHC/Internal/Int.hs - libraries/ghc-internal/src/GHC/Internal/RTS/Flags.hsc - libraries/ghc-internal/src/GHC/Internal/RTS/Flags/Test.hsc - libraries/ghc-internal/src/GHC/Internal/System/Posix/Internals.hs - libraries/ghc-internal/src/GHC/Internal/TopHandler.hs - rts/Interpreter.c Changes: ===================================== compiler/GHC/Tc/Types/Origin.hs ===================================== @@ -83,7 +83,6 @@ import qualified Data.Kind as Hs import Data.List.NonEmpty (NonEmpty (..)) import Data.Maybe (isNothing) import qualified Data.Semigroup as Semi -import GHC.Generics {- ********************************************************************* * * ===================================== hadrian/src/Settings/Flavours/Validate.hs ===================================== @@ -8,7 +8,7 @@ import {-# SOURCE #-} Settings.Default -- Please update doc/flavours.md when changing this file. validateFlavour :: Flavour -validateFlavour = enableLinting $ quickValidateFlavour +validateFlavour = enableLinting $ werror $ quickValidateFlavour { name = "validate" , extraArgs = validateArgs <> defaultHaddockExtraArgs , ghcDebugAssertions = (<= Stage1) ===================================== libraries/ghc-internal/src/GHC/Internal/Conc/IO.hs ===================================== @@ -58,7 +58,7 @@ module GHC.Internal.Conc.IO #endif ) where -import GHC.Internal.Base (otherwise, pure, return, ($)) +import GHC.Internal.Base (otherwise, return, ($)) import GHC.Internal.Conc.Sync as Sync import GHC.Internal.Err (errorWithoutStackTrace) import GHC.Internal.STM as STM @@ -82,6 +82,10 @@ import qualified GHC.Internal.Wasm.Prim.Conc as Wasm import qualified GHC.Internal.Wasm.Prim.Flag as Wasm #endif +#if defined(javascript_HOST_ARCH) +import GHC.Internal.Base (pure) +#endif + ensureIOManagerIsRunning :: IO () #if defined(javascript_HOST_ARCH) ensureIOManagerIsRunning = pure () ===================================== libraries/ghc-internal/src/GHC/Internal/Event/Control.hs ===================================== @@ -29,7 +29,7 @@ module GHC.Internal.Event.Control #include <ghcplatform.h> #include "EventConfig.h" -import GHC.Internal.Base (fmap, otherwise, pure, return, when, ($), (.)) +import GHC.Internal.Base (fmap, otherwise, return, when, ($), (.)) import GHC.Internal.Classes (Eq(..), (&&)) import GHC.Internal.IORef import GHC.Internal.Conc.Signal (Signal) ===================================== libraries/ghc-internal/src/GHC/Internal/Float.hs ===================================== @@ -185,12 +185,12 @@ import GHC.Internal.Prim ( decodeFloat_Int#, divideFloat#, double2Float#, eqWord#, expDouble#, expFloat#, expm1Double#, expm1Float#, fabsDouble#, fabsFloat#, float2Double#, geFloat#, gtFloat#, gtWord#, int2Float#, int2Double#, - int2Word#, int64ToInt#, leFloat#, log1pDouble#, log1pFloat#, logDouble#, + int2Word#, leFloat#, log1pDouble#, log1pFloat#, logDouble#, logFloat#, ltFloat#, ltWord#, minusFloat#, minusWord#, negateDouble#, negateFloat#, negateInt#, plusFloat#, powerFloat#, sinDouble#, sinFloat#, sinhDouble#, sinhFloat#, sqrtDouble#, sqrtFloat#, tanDouble#, tanFloat#, tanhDouble#, tanhFloat#, timesFloat#, uncheckedIShiftRA#, uncheckedShiftL#, - word2Float#, word2Double#, word2Int#, word64ToWord#, + word2Float#, word2Double#, word2Int#, (+#), (+##), (-#), (-##), (*##), (**##), (/##), (<#), (<##), (<=#), (<=##), (>#), (>##), (>=#), (>=##), ) @@ -206,6 +206,13 @@ import GHC.Internal.Float.RealFracMethods import GHC.Internal.Float.ConversionUtils import GHC.Internal.Bignum.BigNat +#if WORD_SIZE_IN_BITS == 64 +import GHC.Internal.Prim ( + int64ToInt#, + word64ToWord#, + ) +#endif + infixr 8 ** -- $setup ===================================== libraries/ghc-internal/src/GHC/Internal/Float/RealFracMethods.hs ===================================== @@ -66,7 +66,7 @@ import GHC.Internal.Classes (Ord(..)) import GHC.Internal.Num () -- instance Num Integer -- (We could remove uses with a little effort) import GHC.Internal.Prim ( - Int#, eqFloat#, decodeFloat_Int#, double2Int#, float2Int#, int2Float#, + eqFloat#, decodeFloat_Int#, double2Int#, float2Int#, int2Float#, int2Double#, int2Word#, ltFloat#, minusFloat#, negateFloat#, negateDouble#, negateInt#, uncheckedIShiftL#, uncheckedIShiftRA#, uncheckedIShiftRL#, (+#), (-#), (<#), (>#), (-##), (==##), (<##), @@ -86,6 +86,10 @@ import GHC.Internal.Prim ( #else +import GHC.Internal.Prim ( + Int#, + ) + #define TO64 integerToInt# #define FROM64 IS #define MINUS64 ( -# ) @@ -355,4 +359,3 @@ foreign import ccall unsafe "rintDouble" foreign import ccall unsafe "rintFloat" c_rintFloat :: Float -> Float - ===================================== libraries/ghc-internal/src/GHC/Internal/Int.hs ===================================== @@ -51,7 +51,7 @@ import GHC.Internal.Classes ( Eq(..), Ord(..), eqInt, neInt, gtInt, geInt, ltInt, leInt, divInt8#, divInt16#, divInt32#, - divModInt8#, divModInt16#, divModInt32#, divModInt#, + divModInt8#, divModInt16#, divModInt32#, modInt8#, modInt16#, modInt32#, (&&), (||), ) @@ -63,6 +63,12 @@ import GHC.Internal.Arr import GHC.Internal.Show import GHC.Internal.Types (Bool(..), Float, Double, Int(..), isTrue#) +#if WORD_SIZE_IN_BITS == 64 +import GHC.Internal.Classes ( + divModInt#, + ) +#endif + ------------------------------------------------------------------------ -- type Int8 ------------------------------------------------------------------------ ===================================== libraries/ghc-internal/src/GHC/Internal/RTS/Flags.hsc ===================================== @@ -66,7 +66,7 @@ import GHC.Internal.Ptr import GHC.Internal.Types (Bool(..), Double, Int) import GHC.Internal.Word import GHC.Internal.Base ( - String, otherwise, pure, return, (.), (++), (<*>), (=<<), + String, otherwise, return, (.), (++), (<*>), (=<<), ) import GHC.Internal.Enum import GHC.Internal.Generics (Generic) @@ -74,6 +74,10 @@ import GHC.Internal.IO import GHC.Internal.Real import GHC.Internal.Show +#if defined(javascript_HOST_ARCH) +import GHC.Internal.Base (pure) +#endif + -- | 'RtsTime' is defined as a @StgWord64@ in @stg/Types.h@ -- -- @since base-4.8.2.0 ===================================== libraries/ghc-internal/src/GHC/Internal/RTS/Flags/Test.hsc ===================================== @@ -8,16 +8,20 @@ module GHC.Internal.RTS.Flags.Test ) where -import GHC.Internal.Base (pure) import GHC.Internal.Ptr -import GHC.Internal.Foreign.C.Types -import GHC.Internal.Foreign.Marshal.Utils import GHC.Internal.Foreign.Storable import GHC.Internal.Data.Functor ((<$>)) import GHC.Internal.Types (Bool(..), Int, IO) import GHC.Internal.Word (Word32) import GHC.Internal.Real (fromIntegral) +#if defined(javascript_HOST_ARCH) +import GHC.Internal.Base (pure) +#else +import GHC.Internal.Foreign.C.Types +import GHC.Internal.Foreign.Marshal.Utils +#endif + #include "Rts.h" #include "rts/Flags.h" ===================================== libraries/ghc-internal/src/GHC/Internal/System/Posix/Internals.hs ===================================== @@ -54,7 +54,6 @@ import GHC.Internal.Base ( import GHC.Internal.Bits import GHC.Internal.Classes (Eq(..), Ord(..), not, (&&), (||)) import GHC.Internal.CString (cstringLength#) -import GHC.Internal.Err (errorWithoutStackTrace) import GHC.Internal.Num import GHC.Internal.Prim (yield#) import GHC.Internal.Real ===================================== libraries/ghc-internal/src/GHC/Internal/TopHandler.hs ===================================== @@ -39,12 +39,12 @@ module GHC.Internal.TopHandler ( import GHC.Internal.Control.Exception import GHC.Internal.Data.Maybe -import GHC.Internal.Classes (Eq(..), Ord(..), (&&)) +import GHC.Internal.Classes (Eq(..),) import GHC.Internal.Foreign.C.Error import GHC.Internal.Foreign.C.Types import GHC.Internal.Foreign.C.String import GHC.Internal.Base ( - String, const, failIO, otherwise, pure, return, ($), (++), (>>), + String, failIO, return, ($), (++), (>>), ) import GHC.Internal.Conc.Sync hiding (throwTo) import GHC.Internal.Prim (Weak#, seq) @@ -67,6 +67,13 @@ import GHC.Internal.Conc.Signal import GHC.Internal.Data.Dynamic (toDyn) #endif +#if !defined(javascript_HOST_ARCH) +import GHC.Internal.Base ( + const, otherwise, + ) +import GHC.Internal.Classes (Ord(..), (&&),) +#endif + -- Note [rts_setMainThread must be called unsafely] -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -- rts_setMainThread must be called as unsafe, because it ===================================== rts/Interpreter.c ===================================== @@ -718,7 +718,7 @@ slow_spw(void *Sp, StgStack *cur_stack, StgWord offset_words){ } // 2b. Access the element if there is no underflow frame, it must be right // at the top of the stack. - else if(Sp_plusW(offset_words) < (StgPtr)(cur_stack->stack + cur_stack->stack_size)) { + else if(Sp_plusW(offset_words) < (void*)(cur_stack->stack + cur_stack->stack_size)) { // Still inside the stack chunk return Sp_plusW(offset_words); } else { @@ -2469,7 +2469,7 @@ run_BCO: threadStackUnderflow(cap, cap->r.rCurrentTSO); LOAD_STACK_POINTERS; by -= sp_to_uf; - } else if (Sp_plusW(by) < (StgPtr)(stk->stack + stk->stack_size)) { + } else if (Sp_plusW(by) < (void*)(stk->stack + stk->stack_size)) { // we're within the first stack chunk, this chunk has // no underflow frame break; View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/13268343203b9839c3c73700be4e34… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/13268343203b9839c3c73700be4e34… You're receiving this email because of your account on gitlab.haskell.org.

1 0

[Git][ghc/ghc] Deleted branch wip/fix-head-js-9.14
by Cheng Shao (＠TerrorJack) 21 Mar '26

21 Mar '26

Cheng Shao deleted branch wip/fix-head-js-9.14 at Glasgow Haskell Compiler / GHC -- You're receiving this email because of your account on gitlab.haskell.org.

1 0

[Git][ghc/ghc][wip/spj-reinstallable-base] Typo
by Simon Peyton Jones (＠simonpj) 21 Mar '26

21 Mar '26

Simon Peyton Jones pushed to branch wip/spj-reinstallable-base at Glasgow Haskell Compiler / GHC Commits: 42a3c032 by Simon Peyton Jones at 2026-03-20T20:27:01+00:00 Typo - - - - - 1 changed file: - compiler/GHC/Iface/Env.hs Changes: ===================================== compiler/GHC/Iface/Env.hs ===================================== @@ -92,7 +92,7 @@ allocateGlobalBinder -> Module -> OccName -> Maybe Unique -> SrcSpan -> IO Name -- See Note [The Name Cache] in GHC.Types.Name.Cache -oallocateGlobalBinder nc mod occ mb_uniq loc +allocateGlobalBinder nc mod occ mb_uniq loc = updateNameCache nc mod occ $ \cache0 -> do case lookupOrigNameCache cache0 mod occ of -- A hit in the cache! We are at the binding site of the name. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/42a3c032b2e6c4d9cf50b35e4e97eab… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/42a3c032b2e6c4d9cf50b35e4e97eab… You're receiving this email because of your account on gitlab.haskell.org.

1 0

[Git][ghc/ghc][wip/spj-reinstallable-base] Wibbles, mainly comments
by Simon Peyton Jones (＠simonpj) 21 Mar '26

21 Mar '26

Simon Peyton Jones pushed to branch wip/spj-reinstallable-base at Glasgow Haskell Compiler / GHC Commits: 93148501 by Simon Peyton Jones at 2026-03-20T20:23:49+00:00 Wibbles, mainly comments - - - - - 5 changed files: - compiler/GHC/Iface/Binary.hs - compiler/GHC/Iface/Env.hs - compiler/GHC/Rename/Env.hs - compiler/GHC/Rename/Names.hs - compiler/GHC/Types/Name.hs Changes: ===================================== compiler/GHC/Iface/Binary.hs ===================================== @@ -654,13 +654,17 @@ initNameWriterTable = do putSymbolTable :: WriteBinHandle -> Int -> UniqFM Name (Int,Name) -> IO () -putSymbolTable bh name_count symtab = do - put_ bh name_count - let names = elems (array (0,name_count-1) (nonDetEltsUFM symtab)) - -- It's OK to use nonDetEltsUFM here because the elements have - -- indices that array uses to create order - mapM_ (\n -> serialiseName bh n symtab) names - +putSymbolTable bh name_count symtab + = do { put_ bh name_count + ; let names = elems (array (0,name_count-1) (nonDetEltsUFM symtab)) + -- It's OK to use nonDetEltsUFM here because the elements + -- have indices that array uses to create order + ; mapM_ serialise_one names } + where + serialise_one :: Name -> IO () + serialise_one name + | (mod, occ, is_known_key) <- extNamePieces name + = put_ bh (moduleUnit mod, moduleName mod, occ, is_known_key) getSymbolTable :: ReadBinHandle -> NameCache -> IO (SymbolTable Name) -- Create an array of Names for the symbols and add them to the NameCache @@ -697,11 +701,6 @@ getSymbolTable bh name_cache ; writeArray mut_arr (fromIntegral i) name ; return new_cache } -serialiseName :: WriteBinHandle -> Name -> UniqFM key (Int,Name) -> IO () -serialiseName bh name _ - | (mod, occ, is_known_key) <- extNamePieces name - = put_ bh (moduleUnit mod, moduleName mod, occ, is_known_key) - -- Note [Symbol table representation of names] -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -- ===================================== compiler/GHC/Iface/Env.hs ===================================== @@ -92,7 +92,7 @@ allocateGlobalBinder -> Module -> OccName -> Maybe Unique -> SrcSpan -> IO Name -- See Note [The Name Cache] in GHC.Types.Name.Cache -allocateGlobalBinder nc mod occ mb_uniq loc +oallocateGlobalBinder nc mod occ mb_uniq loc = updateNameCache nc mod occ $ \cache0 -> do case lookupOrigNameCache cache0 mod occ of -- A hit in the cache! We are at the binding site of the name. ===================================== compiler/GHC/Rename/Env.hs ===================================== @@ -250,6 +250,7 @@ newTopVanillaSrcBinder occ loc = do { this_mod <- getModule -- See if this bindings is for a known-key name, and if so get its Unique + -- See 'Defining known-key names' in GHC.Types.Name ; defines_known_keys <- goptM Opt_DefinesKnownKeyNames ; let mb_uniq :: Maybe Unique mb_uniq | defines_known_keys = lookupOccEnv knownKeyOccMap occ ===================================== compiler/GHC/Rename/Names.hs ===================================== @@ -2025,7 +2025,8 @@ findImportUsage rebindable_known_key_names imports used_gres = acc -- -frebindable-known-key-names is on, and `n` is a known-key name - -- Then don't warn about an unused imports. + -- Then don't warn about an unused import. + -- See (UI2) in Note [Unused imports] | rebindable_known_key_names , isKnownKeyName n = acc @@ -2253,31 +2254,6 @@ warnUnusedImport rdr_env (L loc decl, used, unused, unused_wcs) [ UnusedImportWildcard wc | wc <- unused_wcs ] ++ [ possible_field nm | nm <- sortBy (comparing nameOccName) unused ] -{- -Note [Do not warn about Prelude hiding] -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -We do not warn about - import Prelude hiding( x, y ) -because even if nothing else from Prelude is used, it may be essential to hide -x,y to avoid name-shadowing warnings. Example (#9061) - import Prelude hiding( log ) - f x = log where log = () - - - -Note [Printing minimal imports] -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -To print the minimal imports we walk over all import decls (both user-supplied -and generated), trim their import lists, then filter out generated decls. - -NB that - - * We do *not* change the 'qualified' or 'as' parts! - - * We do not discard a decl altogether; we might need instances - from it. Instead we just trim to an empty import list --} - getMinimalImports :: [ImportDeclUsage] -> RnM [LImportDecl GhcRn] getMinimalImports ie_decls = do { rdr_env <- getGlobalRdrEnv @@ -2399,7 +2375,51 @@ to_ie_post_rn (L l n) | otherwise = L l (IEName noExtField (L (l2l l) n)) where occ = occName n -{- +{- Note [Do not warn about Prelude hiding] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +We do not warn about + import Prelude hiding( x, y ) +because even if nothing else from Prelude is used, it may be essential to hide +x,y to avoid name-shadowing warnings. Example (#9061) + import Prelude hiding( log ) + f x = log where log = () + +Note [Unused imports] +~~~~~~~~~~~~~~~~~~~~~ +In `warnUnusedImport`, if we see an import with an explicit list imports, thus + import M( a, b ) +and neither `a` nor `b` is used, we report the entire import decl as unused. We +check this by looking at the names that it brings into scope scope; if there are +no ununused names, don't report. + +This neatly takes into account two things: + +(UI1) We don't want to complain about `import M()`, because that is often used to bring + M's /instances/ into scope. + +(UI2) In base:Data.Enum we see + import GHC.Internal.Num( Num ) -- For -frebindable-known-key-names (defaulting) + 'Num' is not mentioned explicity but the import is still required; see KKNS_InScope + in Note [Overview of known-key names] in GHC.Types.Name. + + We don't want this import reported at an unused. So `findImportUsage`, when looking + at `import M( x )`, we do /not/ record `x` as "unused" (regardless of whether it is + mentioned in M if + (a) -frebindable-known-key-names is on, and + (b) `x` is a known-key name + +Note [Printing minimal imports] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +To print the minimal imports we walk over all import decls (both user-supplied +and generated), trim their import lists, then filter out generated decls. + +NB that + + * We do *not* change the 'qualified' or 'as' parts! + + * We do not discard a decl altogether; we might need instances + from it. Instead we just trim to an empty import list + Note [Partial export] ~~~~~~~~~~~~~~~~~~~~~ Suppose we have ===================================== compiler/GHC/Types/Name.hs ===================================== @@ -190,6 +190,11 @@ To implement all this, here are the moving parts: This is one reason for (KnownKeyInvariant): an export list cannot have two entities with the same OccName. +* There are two flags that control the treatment of known-key names: + -frebindable-known-key-names + -fdefines-known-key-names + Details in the following bullets. + * Known-key name lookup (normal case: KKNS_FromModule) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In normal client code, suppose the desugarer calls `dsLookupKnownKeyTyCon` @@ -218,18 +223,27 @@ To implement all this, here are the moving parts: to bring into scope some entities that are needed by `dsLookupKnownKeyTyCon` etc. See also wrinkle (KKN1) -* Defin -* There are two flags that control the treatment of known-key names: - -frebindable-known-key-names - -fdefines-known-key-names - -* Suppose the desugarer calls `dsLookupKnownKeyTyCon` on `rationalTyConKey`. - * In client source code, that is, /without/ -frebindable-known-key-names, - we try to import GHC.KnownKeyNames. Assuming this is succesful, +* Defining known-key names + ~~~~~~~~~~~~~~~~~~~~~~~~ + When we /define/ a known-key name, such as + the `Num` class in ghc-internal:GHC.Internal.Num + we must assign the correct Unique. So in GHC.Rename.Env.newTopVanillaSrcBinder + if -fdefines-known-key-names is set (Opt_DefinesKnownKeyNames), we check the + OccName against the list in `basicKnownKeyTable`; if it appears there, we use the + Unique from the table. + +* Serialising known-key names + ~~~~~~~~~~~~~~~~~~~~~~~~~~~ + - When we serialise a known-key name into an interface file, we mark it as such. + See `serialise_one` in GHC.Iface.Binary.putSymbolTable. + - When deserialising a name from an interface file, we check the known-key bit, + If it is set, we get the Unique from the `basicKnownKeyTable`, + and use `mkKnownKeyName` rather than `mkExternalName` to build the Name. Wrinkles -(KKN1) In +(KKN1) We need some special treatment of unused-import warnings. + See (UI1) in Note [Unused imports] in GHC.Rename.Names Note [About the NameSorts] ~~~~~~~~~~~~~~~~~~~~~~~~~~ View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/93148501b5e0598ba606a083131884d… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/93148501b5e0598ba606a083131884d… You're receiving this email because of your account on gitlab.haskell.org.

1 0

[Git][ghc/ghc] Deleted branch wip/ghc-internal-whack-a-mole
by Cheng Shao (＠TerrorJack) 21 Mar '26

21 Mar '26

Cheng Shao deleted branch wip/ghc-internal-whack-a-mole at Glasgow Haskell Compiler / GHC -- You're receiving this email because of your account on gitlab.haskell.org.

1 0

[Git][ghc/ghc][wip/validate-fix-werror] 21 commits: ghci: Mention active language edition in startup banner
by Cheng Shao (＠TerrorJack) 21 Mar '26

21 Mar '26

Cheng Shao pushed to branch wip/validate-fix-werror at Glasgow Haskell Compiler / GHC Commits: e34cb6da by Adam Gundry at 2026-03-20T12:20:00-04:00 ghci: Mention active language edition in startup banner Per GHC proposal 632, this makes the GHCi startup banner include the active language edition, plus an indication of whether this was the default (as opposed to being explicitly selected via an option such as `-XGHC2024`). For example: ``` $ ghci GHCi, version 9.14.1: https://www.haskell.org/ghc/ :? for help Using default language edition: GHC2024 ghci> ``` Fixes #26037. - - - - - 52c3e6ba by sheaf at 2026-03-20T12:21:09-04:00 Improve incomplete record selector warnings This commit stops GHC from emitting spurious incomplete record selector warnings for bare selectors/projections such as .fld There are two places we currently emit incomplete record selector warnings: 1. In the desugarer, when we see a record selector or an occurrence of 'getField'. Here, we can use pattern matching information to ensure we don't give false positives. 2. In the typechecker, which might sometimes give false positives but can emit warnings in cases that the pattern match checker would otherwise miss. This is explained in Note [Detecting incomplete record selectors] in GHC.HsToCore.Pmc. Now, we obviously don't want to emit the same error twice, and generally we prefer (1), as those messages contain fewer false positives. So we suppress (2) when we are sure we are going to emit (1); the logic for doing so is in GHC.Tc.Instance.Class.warnIncompleteRecSel, and works by looking at the CtOrigin. Now, the issue was that this logic handled explicit record selectors as well as overloaded record field selectors such as "x.r" (which turns into a simple GetFieldOrigin CtOrigin), but it didn't properly handle record projectors like ".fld" or ".fld1.fld2" (which result in other CtOrigins such as 'RecordFieldProjectionOrigin'). To solve this problem, we re-use the 'isHasFieldOrigin' introduced in fbdc623a (slightly adjusted). On the way, we also had to update the desugarer with special handling for the 'ExpandedThingTc' case in 'ds_app', to make sure that 'ds_app_var' sees all the type arguments to 'getField' in order for it to indeed emit warnings like in (1). Fixes #26686 - - - - - 309d7e87 by Cheng Shao at 2026-03-20T12:21:53-04:00 rts: opportunistically grow the MutableByteArray# in-place in resizeMutableByteArray# Following !15234, this patch improves `resizeMutableByteArray#` memory efficiency by growing the `MutableByteArray#` in-place if possible, addressing an old todo comment here. Also adds a new test case `resizeMutableByteArrayInPlace` that stresses this behavior. - - - - - 7d4ef162 by Matthew Craven at 2026-03-20T12:22:47-04:00 Change representation of floating point literals This commit changes the representation of floating point literals throughough the compiler, in particular in Core and Cmm. The Rational type is deficient for this purpose, dealing poorly with NaN, +/-Infinity, and negative zero. Instead, the new module GHC.Types.Literal.Floating uses the host Float/Double type to represent NaNs, infinities and negative zero. It also contains a Rational constructor, for the benefit of -fexcess-precision. Other changes: - Remove Note [negative zero] and related code This also removes the restrictions on constant-folding of division by zero, and should make any problems with NaN/Infinity more obvious. - Use -0.0 as the additive identity for Core constant folding rules for floating-point addition, fixing #21227. - Manual worker-wrapper for GHC.Float.rationalToDouble. This is intended to prevent the compiler's WW on this function from interfering with constant-folding. This change means that we now avoid allocating a box for the result of a 'realToFrac' call in T10359. - Combine floatDecodeOp and doubleDecodeOp. This change also fixes a bug in doubleDecodeOp wherein it would incorrectly produce an Int# instead of an Int64# literal for the mantissa component with 64-bit targets. - Use Float/Double for assembly immediates, and update the X86 and PowerPC backends to properly handle special values such as NaN and infinity. - Allow 'rational_to' to handle zero denominators, fixing a TODO in GHC.Core.Opt.ConstantFold. Fixes #8364 #9811 #18897 #21227 Progress towards #26919 Metric Decrease: T10359 Co-authored-by: sheaf <sam.derbyshire(a)gmail.com> ------------------------- Metric Decrease: T1969 T5321FD ------------------------- - - - - - 80e2dd4f by Zubin Duggal at 2026-03-20T12:23:33-04:00 compiler/ffi: Collapse void pointer chains in capi wrappers New gcc/clang treat -Wincompatible-pointer-types as an error by default. Since C only allows implicit conversion from void*, not void**, capi wrappers for functions taking e.g. abstract** would fail to compile when the Haskell type Ptr (Ptr Abstract) was naively translated to void**. Collapse nested void pointers to a single void* when the pointee type has no known C representation. Fixes #26852 - - - - - 1c50bd7b by Luite Stegeman at 2026-03-20T12:24:37-04:00 Move some functions related to pointer tagging to a separate module - - - - - bfd7aafd by Luite Stegeman at 2026-03-20T12:24:37-04:00 Branchless unpacking for enumeration types Change unpacking for enumeration types to go to Word8#/Word16#/Word# directly instead of going through an intermediate unboxed sum. This allows us to do a branchless conversion using DataToTag and TagToEnum. Fixes #26970 - - - - - 72b20fc0 by Luite Stegeman at 2026-03-20T12:25:30-04:00 bytecode: Carefully SLIDE off the end of a stack chunk The SLIDE bytecode instruction was not checking for stack chunk boundaries and could corrupt the stack underflow frame, leading to crashes. We add a check to use safe writes if we cross the chunk boundary and also handle stack underflow if Sp is advanced past the underflow frame. fix #27001 - - - - - 2e22b43c by Cheng Shao at 2026-03-20T12:26:14-04:00 ghci: serialize BCOByteArray buffer directly when possible This patch changes the `Binary` instances of `BCOByteArray` to directly serialize the underlying buffer when possible, while also taking into account the issue of host-dependent `Word` width. See added comments and amended `Note [BCOByteArray serialization]` for detailed explanation. Closes #27020. - - - - - 89d9ba37 by Sylvain Henry at 2026-03-20T12:27:34-04:00 JS: replace BigInt with Number arithmetic for 32/64-bit quot/rem (#23597) Replace BigInt-based implementations of quotWord32, remWord32, quotRemWord32, quotRem2Word32, quotWord64, remWord64, quotInt64, and remInt64 with pure Number (double/integer) arithmetic to avoid the overhead of BigInt promotion. - - - - - ae4ddd60 by Sylvain Henry at 2026-03-20T12:28:28-04:00 Core: add constant-folding rules for Addr# eq/ne (#18032) - - - - - 3e767f98 by Matthew Pickering at 2026-03-20T12:29:11-04:00 Use OsPath rather than FilePath in Downsweep cache This gets us one step closure to uniformly using `OsPath` in the compiler. - - - - - 2c57de29 by Cheng Shao at 2026-03-20T12:29:55-04:00 hadrian: fix ghc-in-ghci flavour stage0 shared libraries This patch fixes missing stage0 shared libraries in hadrian ghc-in-ghci flavour, which was accidentally dropped in 669d09f950a6e88b903d9fd8a7571531774d4d5d and resulted in a regression in HLS support on linux/macos. Fixes #27057. - - - - - 5b1be555 by Sylvain Henry at 2026-03-20T12:30:48-04:00 JS: install rts/Types.h header file (#27033) It was an omission, making HsFFI.h not usable with GHC using the JS backend. - - - - - b883f08f by Cheng Shao at 2026-03-20T12:31:33-04:00 hadrian: don't compile RTS with -Winline This patch removes `-Winline` from cflags when compiling the RTS, given that: 1. It generates a huge pile of spam and hurts developer experience 2. Whether inlining happens is highly dependent on toolchains, flavours, etc, and it's not really an issue to fix if inlining doesn't happen; it's a hint to the C compiler anyway. Fixes #27060. - - - - - 333387d6 by Cheng Shao at 2026-03-20T12:31:33-04:00 hadrian: compile libffi-clib with -Wno-deprecated-declarations This patch adds `-Wno-deprecated-declarations` to cflags of `libffi-clib`, given that it produces noise at compile-time that aren't really our issue to fix anyway, it's from vendored libffi source code. - - - - - 67c47771 by Rodrigo Mesquita at 2026-03-20T12:32:17-04:00 Expose decodeStackWithIpe from ghc-experimental This decoding is useful to the debugger and it wasn't originally exported as an oversight. - - - - - 0cb532cd by Cheng Shao at 2026-03-20T20:02:36+00:00 rts: fix -Wcompare-distinct-pointer-types errors This commit fixes `-Wcompare-distinct-pointer-types` errors in the RTS which should have been caught by the `validate` flavour but was warnings in CI due to the recent `+werror` regression. - - - - - af543550 by Cheng Shao at 2026-03-20T20:02:36+00:00 ghc-internal: fix unused imports This commit fixes unused imports in `ghc-internal` which should have been caught by the `validate` flavour but was warnings in CI due to the recent `+werror` regression. Fixes #27059. - - - - - f14f93c8 by Cheng Shao at 2026-03-20T20:02:36+00:00 compiler: fix unused imports in GHC.Tc.Types.Origin This commit fixes unused imports in `GHC.Tc.Types.Origin` which should have been caught by the `validate` flavour but was warnings in CI due to the recent `+werror` regression. Fixes #27059. - - - - - 13268343 by Cheng Shao at 2026-03-20T20:02:36+00:00 hadrian: fix missing +werror in validate flavour This patch fixes missing `+werror` in validate flavour, which was an oversight in bb3a2ba1eefadf0b2ef4f39b31337a23eec67f29. Fixes #27066. - - - - - 108 changed files: - compiler/GHC/Builtin/Names.hs - compiler/GHC/ByteCode/Asm.hs - compiler/GHC/Cmm/CommonBlockElim.hs - compiler/GHC/Cmm/Expr.hs - compiler/GHC/Cmm/Opt.hs - compiler/GHC/Cmm/Parser.y - compiler/GHC/Cmm/Type.hs - compiler/GHC/Cmm/Utils.hs - compiler/GHC/CmmToAsm/AArch64/CodeGen.hs - compiler/GHC/CmmToAsm/AArch64/Ppr.hs - compiler/GHC/CmmToAsm/AArch64/Regs.hs - compiler/GHC/CmmToAsm/LA64/CodeGen.hs - compiler/GHC/CmmToAsm/LA64/Ppr.hs - compiler/GHC/CmmToAsm/LA64/Regs.hs - compiler/GHC/CmmToAsm/PPC/CodeGen.hs - compiler/GHC/CmmToAsm/PPC/Ppr.hs - compiler/GHC/CmmToAsm/PPC/Regs.hs - compiler/GHC/CmmToAsm/RV64/CodeGen.hs - compiler/GHC/CmmToAsm/RV64/Ppr.hs - compiler/GHC/CmmToAsm/RV64/Regs.hs - compiler/GHC/CmmToAsm/Wasm/FromCmm.hs - compiler/GHC/CmmToAsm/X86/CodeGen.hs - compiler/GHC/CmmToAsm/X86/Ppr.hs - compiler/GHC/CmmToAsm/X86/Regs.hs - compiler/GHC/CmmToC.hs - compiler/GHC/CmmToLlvm/CodeGen.hs - compiler/GHC/CmmToLlvm/Data.hs - compiler/GHC/Core.hs - compiler/GHC/Core/Make.hs - compiler/GHC/Core/Opt/ConstantFold.hs - compiler/GHC/Driver/Downsweep.hs - compiler/GHC/HsToCore/Expr.hs - compiler/GHC/HsToCore/Foreign/C.hs - compiler/GHC/HsToCore/Match/Literal.hs - compiler/GHC/HsToCore/Pmc.hs - compiler/GHC/HsToCore/Pmc/Solver/Types.hs - + compiler/GHC/Platform/Tag.hs - compiler/GHC/Stg/Unarise.hs - compiler/GHC/StgToByteCode.hs - compiler/GHC/StgToCmm/Closure.hs - compiler/GHC/StgToCmm/Expr.hs - compiler/GHC/StgToCmm/Lit.hs - compiler/GHC/StgToCmm/Prim.hs - compiler/GHC/StgToJS/Literal.hs - compiler/GHC/Tc/Errors.hs - compiler/GHC/Tc/Instance/Class.hs - compiler/GHC/Tc/TyCl/Build.hs - compiler/GHC/Tc/Types/Origin.hs - compiler/GHC/Types/Id/Make.hs - compiler/GHC/Types/Literal.hs - + compiler/GHC/Types/Literal/Floating.hs - compiler/GHC/Types/RepType.hs - compiler/GHC/Utils/Binary.hs - compiler/ghc.cabal.in - docs/users_guide/9.16.1-notes.rst - ghc/GHCi/UI.hs - ghc/Main.hs - hadrian/src/Settings/Flavours/GhcInGhci.hs - hadrian/src/Settings/Flavours/Validate.hs - hadrian/src/Settings/Packages.hs - libraries/ghc-experimental/ghc-experimental.cabal.in - + libraries/ghc-experimental/src/GHC/Stack/Decode/Experimental.hs - libraries/ghc-internal/src/GHC/Internal/Conc/IO.hs - libraries/ghc-internal/src/GHC/Internal/Event/Control.hs - libraries/ghc-internal/src/GHC/Internal/Float.hs - libraries/ghc-internal/src/GHC/Internal/RTS/Flags.hsc - libraries/ghc-internal/src/GHC/Internal/RTS/Flags/Test.hsc - libraries/ghc-internal/src/GHC/Internal/System/Posix/Internals.hs - libraries/ghc-internal/src/GHC/Internal/TopHandler.hs - libraries/ghci/GHCi/ResolvedBCO.hs - rts/Interpreter.c - rts/PrimOps.cmm - rts/js/arith.js - rts/rts.cabal - + testsuite/tests/bytecode/T27001.hs - + testsuite/tests/bytecode/T27001.stdout - testsuite/tests/bytecode/all.T - + testsuite/tests/codeGen/should_run/T21227.hs - + testsuite/tests/codeGen/should_run/T21227.stdout - + testsuite/tests/codeGen/should_run/T9811.hs - + testsuite/tests/codeGen/should_run/T9811.stdout - testsuite/tests/codeGen/should_run/all.T - testsuite/tests/count-deps/CountDepsAst.stdout - testsuite/tests/count-deps/CountDepsParser.stdout - + testsuite/tests/ffi/should_compile/T26852.h - + testsuite/tests/ffi/should_compile/T26852.hs - + testsuite/tests/ffi/should_compile/T26852.stderr - testsuite/tests/ffi/should_compile/all.T - testsuite/tests/ghci/should_run/BinaryArray.hs - testsuite/tests/interface-stability/ghc-experimental-exports.stdout - testsuite/tests/interface-stability/ghc-experimental-exports.stdout-mingw32 - + testsuite/tests/javascript/js-c-sources/T27033.hs - + testsuite/tests/javascript/js-c-sources/T27033.stdout - + testsuite/tests/javascript/js-c-sources/T27033_c.c - + testsuite/tests/javascript/js-c-sources/T27033_js.js - testsuite/tests/javascript/js-c-sources/all.T - testsuite/tests/numeric/should_run/T7014.hs - + testsuite/tests/overloadedrecflds/should_compile/T26686.hs - + testsuite/tests/overloadedrecflds/should_compile/T26686.stderr - testsuite/tests/overloadedrecflds/should_compile/all.T - testsuite/tests/rts/all.T - + testsuite/tests/rts/resizeMutableByteArrayInPlace.hs - + testsuite/tests/simplCore/should_compile/T18032.hs - + testsuite/tests/simplCore/should_compile/T18032.stderr - testsuite/tests/simplCore/should_compile/all.T - testsuite/tests/simplStg/should_run/all.T - + testsuite/tests/simplStg/should_run/unpack_enum.hs - + testsuite/tests/simplStg/should_run/unpack_enum.stdout The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/ec230141b747a805347d45c54e9a94… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/ec230141b747a805347d45c54e9a94… You're receiving this email because of your account on gitlab.haskell.org.

1 0

[Git][ghc/ghc][wip/spj-reinstallable-base] 2 commits: Import wibbles
by Simon Peyton Jones (＠simonpj) 21 Mar '26

21 Mar '26

Simon Peyton Jones pushed to branch wip/spj-reinstallable-base at Glasgow Haskell Compiler / GHC Commits: c77dfcec by Simon Peyton Jones at 2026-03-20T17:38:25+00:00 Import wibbles - - - - - fd037c83 by Simon Peyton Jones at 2026-03-20T19:42:39+00:00 Wibbles - - - - - 7 changed files: - compiler/GHC/Driver/Downsweep.hs - compiler/GHC/Driver/Pipeline/Execute.hs - compiler/GHC/HsToCore/Monad.hs - compiler/GHC/Iface/Load.hs - compiler/GHC/Tc/Utils/Env.hs - compiler/GHC/Types/Name.hs - nofib Changes: ===================================== compiler/GHC/Driver/Downsweep.hs ===================================== @@ -27,7 +27,6 @@ import GHC.Prelude import GHC.Platform.Ways import GHC.Driver.Config.Finder (initFinderOpts) -import GHC.Driver.Config.Parser (initParserOpts) import GHC.Driver.DynFlags import GHC.Driver.Phases import {-# SOURCE #-} GHC.Driver.Pipeline (preprocess) @@ -59,7 +58,6 @@ import qualified GHC.Data.Maybe as M import GHC.Data.OsPath ( unsafeEncodeUtf ) import GHC.Data.StringBuffer import GHC.Data.Graph.Directed.Reachability -import qualified GHC.LanguageExtensions as LangExt import GHC.Utils.Exception ( throwIO, SomeAsyncException ) import GHC.Utils.Outputable ===================================== compiler/GHC/Driver/Pipeline/Execute.hs ===================================== @@ -28,7 +28,6 @@ import GHC.Unit.Module.ModIface import GHC.Driver.Backend import GHC.Driver.Session import GHC.Unit.Module.ModSummary -import qualified GHC.LanguageExtensions as LangExt import GHC.Types.SrcLoc import GHC.Driver.Main import GHC.Driver.Downsweep ===================================== compiler/GHC/HsToCore/Monad.hs ===================================== @@ -81,7 +81,7 @@ import GHC.Core.Type import GHC.Core.Multiplicity import GHC.IfaceToCore -import GHC.Iface.Load( lookupKnownKeyThing ) +import GHC.Iface.Load( KnownKeyNameSource(..), lookupKnownKeyThing ) import GHC.Tc.Utils.Monad @@ -567,8 +567,8 @@ dsLookupKnownKey :: KnownKeyNameKey -> DsM TyThing dsLookupKnownKey uniq = do { rebindable_path <- goptM Opt_RebindableKnownKeyNames ; mb_rdr_env <- if rebindable_path - then Just <$> dsGetGlobalRdrEnv - else return Nothing + then KKNS_InScope <$> dsGetGlobalRdrEnv + else return KKNS_FromModule ; dsToIfL $ do { mb_res <- lookupKnownKeyThing mb_rdr_env uniq ; case mb_res of ===================================== compiler/GHC/Iface/Load.hs ===================================== @@ -17,9 +17,11 @@ module GHC.Iface.Load ( -- Importing one thing importDecl, checkWiredInTyCon, ifCheckWiredInThing, - lookupKnownKeyThing, lookupKnownKeyName, loadGlobalName, + -- Known-key things + KnownKeyNameSource(..), lookupKnownKeyThing, lookupKnownKeyName, + -- RnM/TcM functions loadModuleInterface, loadModuleInterfaces, loadSrcInterface, loadSrcInterface_maybe, @@ -135,17 +137,33 @@ import qualified GHC.Unit.Home.Graph as HUG * * ********************************************************************* -} +data KnownKeyNameSource + = KKNS_InScope GlobalRdrEnv + -- Look up the known-key name in this GlobalRdrEnv, which + -- is the top-level scope of the current module. + -- This happens when -frebindable-known-key-name is set, usually when + -- we are compiling `ghc-internal` or `base` + + | KKNS_FromModule + -- Look up the known-key name in the export list of GHC.KnownKeyNames + -- This is the "normal path", and happens when -frebindable-known-key-name + -- is /not/ set + +instance Outputable KnownKeyNameSource where + ppr KKNS_FromModule = text "FromModule" + ppr (KKNS_InScope env) = text "InScope" <> braces (ppr env) + lookupKnownKeyThing :: HasDebugCallStack - => Maybe GlobalRdrEnv -> KnownKeyNameKey + => KnownKeyNameSource -> KnownKeyNameKey -> IfM lcl (MaybeErr IfaceMessage TyThing) lookupKnownKeyThing mb_gbl_rdr_env key = do { name <- lookupKnownKeyName mb_gbl_rdr_env key ; lookupGlobalName name } lookupKnownKeyName :: HasDebugCallStack - => Maybe GlobalRdrEnv -> KnownKeyNameKey + => KnownKeyNameSource -> KnownKeyNameKey -> IfM lcl Name -lookupKnownKeyName Nothing uniq +lookupKnownKeyName KKNS_FromModule uniq = do { known_key_name_map :: UniqFM KnownKeyNameKey Name <- loadKnownKeyOccMap ; let name = lookupUFM known_key_name_map uniq `orElse` pprPanic "lookupKnownKeyThing 1" @@ -155,7 +173,7 @@ lookupKnownKeyName Nothing uniq 2 (ppr name <+> ppr uniq) ; return name } -lookupKnownKeyName (Just gbl_rdr_env) uniq +lookupKnownKeyName (KKNS_InScope gbl_rdr_env) uniq -- Just gbl_rdr_env: we have -frebindable-known-key-names on, and -- here is the top-level GlobalRdrEnv -- Look up the known-key OccName in the GlobalRdrEnv @@ -212,6 +230,7 @@ loadKnownKeyOccMap where doc = text "Need interface for KnonwKeyNames" +#ifdef DEBUG checkKnownKeyNamesIface :: KnownKeyNameMap -> Maybe SDoc -- Check that KnownKeyNames exports all the things defined in `basicKnownKeyTable` -- and the the uniques and occ-names agree @@ -223,6 +242,7 @@ checkKnownKeyNamesIface known_key_names_occ_map is_bad (occ, key) = case lookupUFM known_key_names_occ_map key of Nothing -> True Just name -> getOccName name /= occ +#endif {- ********************************************************************* * * ===================================== compiler/GHC/Tc/Utils/Env.hs ===================================== @@ -509,8 +509,8 @@ tcLookupKnownKeyGlobal :: HasDebugCallStack => Unique -> TcM TyThing tcLookupKnownKeyGlobal uniq = do { rebindable_path <- goptM Opt_RebindableKnownKeyNames ; mb_rdr_env <- if rebindable_path - then Just <$> getGlobalRdrEnv - else return Nothing + then KKNS_InScope <$> getGlobalRdrEnv + else return KKNS_FromModule ; traceTc "tcLookupKnownKeyGlobal" (ppr rebindable_path $$ ppr mb_rdr_env) ; mb_thing <- initIfaceTcRn (lookupKnownKeyThing mb_rdr_env uniq) ; case mb_thing of ===================================== compiler/GHC/Types/Name.hs ===================================== @@ -180,6 +180,45 @@ To implement all this, here are the moving parts: knownKeyUniqMap :: UniqFM KnownKeyNameKey OccName +* A new module `base:GHC.KnownKeyNames` exports all the known-key names. + There is nothing special about this module except that GHC knows its + name and can import it. + + In effect, the `mi_exports` of `GHC/KnownKeyNames.hi` tells GHC where each + known-key name is defined. + + This is one reason for (KnownKeyInvariant): an export list cannot have two + entities with the same OccName. + +* Known-key name lookup (normal case: KKNS_FromModule) + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + In normal client code, suppose the desugarer calls `dsLookupKnownKeyTyCon` + on `rationalTyConKey`. Then, in `loadKnownKeyOccMap` + * GHC imports GHC.KnownKeyNames, i.e. looks for `GHC/KnownKeyNames.hi` + * Assuming this is successful, GHC usees its `mi_exports` to builds a mapping + `KnownKeyNameMap` from each known-key unique to the Name of the entity. + * It stashes this map in the `eps_known_keys` field of the ExternalPackageState + so that it doesn't need to repeat the exercise. + Now it can simplhy look up `rationalTyConKey` in the `eps_known_keys`. Easy! + See `dsLookupKnownKeyName`. + +* Known-key name lookup (base case: KKNS_InScope) + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + We can't follow the above plan when compiling modules in `base` or `ghc-internal` because + GHC.KnownKeyNames has not yet been compiled! Instead, we use whatever is in scope with + the desired `OccName`, rather like `-XRebindableSyntax`. + + See the `KnownKeyNameSource` argument to `lookupKnownKeyName`. When compiling modules + in `ghc-internal` or `base`: + * We switch on -frebindable-known-key-names + * That ensures that we pass `KKNS_InScope` to `lookupKnownKeyName` + * The latter now looks in the GlobalRdrEnv it is passed. + + This does mean that in `base` and `ghc-internal` we occasionally need an extra import + to bring into scope some entities that are needed by `dsLookupKnownKeyTyCon` etc. + See also wrinkle (KKN1) + +* Defin * There are two flags that control the treatment of known-key names: -frebindable-known-key-names -fdefines-known-key-names @@ -188,6 +227,10 @@ To implement all this, here are the moving parts: * In client source code, that is, /without/ -frebindable-known-key-names, we try to import GHC.KnownKeyNames. Assuming this is succesful, +Wrinkles + +(KKN1) In + Note [About the NameSorts] ~~~~~~~~~~~~~~~~~~~~~~~~~~ 1. Initially: ===================================== nofib ===================================== @@ -1 +1 @@ -Subproject commit ae985b599e958414b327e4f220d99b7248601d55 +Subproject commit b7391df4540ac8b11b35e1b2e2c15819b5171798 View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/f8a69d19f61a61831bb74a91e88b9c… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/f8a69d19f61a61831bb74a91e88b9c… You're receiving this email because of your account on gitlab.haskell.org.

1 0

[Git][ghc/ghc][wip/spj-apporv-Oct24] update Note to include HsExpansion
by Apoorv Ingle (＠ani) 21 Mar '26

21 Mar '26

Apoorv Ingle pushed to branch wip/spj-apporv-Oct24 at Glasgow Haskell Compiler / GHC Commits: 148cf865 by Apoorv Ingle at 2026-03-20T14:20:03-05:00 update Note to include HsExpansion - - - - - 1 changed file: - compiler/GHC/Tc/Gen/Expr.hs Changes: ===================================== compiler/GHC/Tc/Gen/Expr.hs ===================================== @@ -572,7 +572,8 @@ tcExpr (HsDo _ do_or_lc stmts) res_ty = do hse <- expandDoStmts do_or_lc stmts tcHsExpansion hse res_ty | otherwise - -- ListComp, MonadComp are handled by tcDoStmts + -- ListComp and MonadComp are handled by legacy tcDoStmts for now, + -- The ultimate goal is to handle them via expandDoStmts. -- GHCiStmts are handled completely separate = tcDoStmts do_or_lc stmts res_ty @@ -786,15 +787,16 @@ directly, it's much easier to * Expand (or desugar) the code to something simpler * Typecheck that simpler expression -Example: record updates. The typechecker looks like this: +Example: Typechecking the do expression. The typechecker looks (somewhat) like this: - tcExpr e@(HsDo{}) rho = do { ee <- expandExpr e - ; tcExpr ee rho } + tcExpr e@(HsDo _ stmts) rho = do { hse <- expandDoStmts stmts + ; tcHsExpansion hse rho } -The `expandExpr` replaces the HsDo { x <- e1; return x } +The `expandDoStmts` replaces the HsDo { x <- e1; return x } with something like - e1 >>= \ x -> x -and we then typecheck the latter. + HSE { hs_ctxt = e + , expanded_expr = e1 >>= \ x -> x } +and we then typecheck the expression `e1 >>= \ x -> x` See also Note [Handling overloaded and rebindable constructs] and Note [Doing XXExprGhcRn in the Renamer vs Typechecker] @@ -806,8 +808,8 @@ The rest of this Note explains how that is done. * The expansion process typically takes a user written thing L lspan ue and returns - L lspan (XExpr (ExpandedThingRn { xrn_orig = ue - , xrn_expanded = ee } )) + L lspan (XExpr (ExpandedThingRn (HSE { hs_ctxt = ue + , expanded_expr = ee } )) where `ee` is the expansion of the user written thing `ue` * The type checker context has 3 key fields that describe the context: @@ -824,30 +826,29 @@ The rest of this Note explains how that is done. The `tcl_in_gen_code` is a boolean that keeps track of whether the current expression being typechecked is compiler generated or user generated. + INVARIANT: `tcl_in_gen_code` is modified only in `setSrcSpan`. - The `tcl_in_gen_code` is a boolean that keeps track of whether - the current expression being typechecked is compiler generated - or user generated. * Now, when tcMonoLExpr :: LHsExpr GhcRn -> ExpRhoType -> TcM (HsExpr GhcTc) gets a located expression, it does 2 things: - * Calls `addLExprCtxt` to perform error context management - * Calls `tcExpr` to typecheck the expression. + (a) Calls `addLExprCtxt` to perform error context management + (b) Calls `tcExpr` to typecheck the expression. -* `addLExprCtxt span expr` +(a) `addLExprCtxt span expr` (1) updates the location of `tcl_loc` with the `span` above, (2) adds an `ErrCtxt` on top of the `tcl_err_ctxt`. * However, if the `span` is generated (see `isGeneratedSrcSpan`), then - `addLExprCtxt` is a no-op. Crucially, when we generate code in `expandExpr`, + `addLExprCtxt` sets `tcl_in_gen_code` to `True` via a call to `setSrcSpan` + and the `tcl_err_ctxt` is left untouched. Crucially, when we generate code in `expandExpr`, all the generated AST notes are tagged with a `GeneratedSrcSpan`. This is how we avoid populating the TcLclCtxt with generated code. -* The type checker error-stack element `GHC.Tc.Types.ErrCtxt.ErrCtxt` - type ErrCtxt = HsCtxt +* The type checker error-stack element `GHC.Tc.Types.ErrCtxt.HsCtxt` + just stores an error message - just stores an error message + type ErrCtxt = HsCtxt When called on an `XExpr`, `addLExprCtxt`, adds the user written thing `ue`, and the error message provided by the caller on the `ErrCtxtStack` See @@ -857,10 +858,9 @@ The rest of this Note explains how that is done. tcHsExpansion :: HsExpansion GhcRn -> ExpRhoType -> TcM (HsExpr GhcTc) tcHsExpansion (HSE o e) res_ty - = mkExpandedTc o <$> -- necessary for hpc ticks - -- Need to call tcExpr and not tcApp - -- as e can be let statement which tcApp cannot gracefully handle - tcMonoLExpr e res_ty + = do e' <- tcMonoLExpr e res_ty + return $ XExpr (ExpandedThingTc (HSE o e')) + {- ************************************************************************ View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/148cf86589b3f671206f31494b24548… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/148cf86589b3f671206f31494b24548… You're receiving this email because of your account on gitlab.haskell.org.

1 0

[Git][ghc/ghc][wip/spj-apporv-Oct24] update Note to include HsExpansion
by Apoorv Ingle (＠ani) 21 Mar '26

21 Mar '26

Apoorv Ingle pushed to branch wip/spj-apporv-Oct24 at Glasgow Haskell Compiler / GHC Commits: 8b3ded23 by Apoorv Ingle at 2026-03-20T13:28:22-05:00 update Note to include HsExpansion - - - - - 1 changed file: - compiler/GHC/Tc/Gen/Expr.hs Changes: ===================================== compiler/GHC/Tc/Gen/Expr.hs ===================================== @@ -572,7 +572,8 @@ tcExpr (HsDo _ do_or_lc stmts) res_ty = do hse <- expandDoStmts do_or_lc stmts tcHsExpansion hse res_ty | otherwise - -- ListComp, MonadComp are handled by tcDoStmts + -- ListComp and MonadComp are handled by legacy tcDoStmts for now, + -- The ultimate goal is to handle them via expandDoStmts. -- GHCiStmts are handled completely separate = tcDoStmts do_or_lc stmts res_ty @@ -786,15 +787,16 @@ directly, it's much easier to * Expand (or desugar) the code to something simpler * Typecheck that simpler expression -Example: record updates. The typechecker looks like this: +Example: Typechecking the do expression. The typechecker looks (somewhat) like this: - tcExpr e@(HsDo{}) rho = do { ee <- expandExpr e - ; tcExpr ee rho } + tcExpr e@(HsDo _ stmts) rho = do { hse <- expandDoStmts stmts + ; tcHsExpansion hse rho } -The `expandExpr` replaces the HsDo { x <- e1; return x } +The `expandDoStmts` replaces the HsDo { x <- e1; return x } with something like - e1 >>= \ x -> x -and we then typecheck the latter. + HSE { hs_ctxt = e + , expanded_expr = e1 >>= \ x -> x } +and we then typecheck the expression `e1 >>= \ x -> x` See also Note [Handling overloaded and rebindable constructs] and Note [Doing XXExprGhcRn in the Renamer vs Typechecker] @@ -806,8 +808,8 @@ The rest of this Note explains how that is done. * The expansion process typically takes a user written thing L lspan ue and returns - L lspan (XExpr (ExpandedThingRn { xrn_orig = ue - , xrn_expanded = ee } )) + L lspan (XExpr (ExpandedThingRn (HSE { hs_ctxt = ue + , expanded_expr = ee } )) where `ee` is the expansion of the user written thing `ue` * The type checker context has 3 key fields that describe the context: @@ -824,30 +826,29 @@ The rest of this Note explains how that is done. The `tcl_in_gen_code` is a boolean that keeps track of whether the current expression being typechecked is compiler generated or user generated. + INVARIANT: `tcl_in_gen_code` is modified only in `setSrcSpan`. - The `tcl_in_gen_code` is a boolean that keeps track of whether - the current expression being typechecked is compiler generated - or user generated. * Now, when tcMonoLExpr :: LHsExpr GhcRn -> ExpRhoType -> TcM (HsExpr GhcTc) gets a located expression, it does 2 things: - * Calls `addLExprCtxt` to perform error context management - * Calls `tcExpr` to typecheck the expression. + (a) Calls `addLExprCtxt` to perform error context management + (b) Calls `tcExpr` to typecheck the expression. -* `addLExprCtxt span expr` +(a) `addLExprCtxt span expr` (1) updates the location of `tcl_loc` with the `span` above, (2) adds an `ErrCtxt` on top of the `tcl_err_ctxt`. * However, if the `span` is generated (see `isGeneratedSrcSpan`), then - `addLExprCtxt` is a no-op. Crucially, when we generate code in `expandExpr`, + `addLExprCtxt` sets `tcl_in_gen_code` to `True` via a call to `setSrcSpan` + and the `tcl_err_ctxt` is left untouched. Crucially, when we generate code in `expandExpr`, all the generated AST notes are tagged with a `GeneratedSrcSpan`. This is how we avoid populating the TcLclCtxt with generated code. -* The type checker error-stack element `GHC.Tc.Types.ErrCtxt.ErrCtxt` - type ErrCtxt = HsCtxt +* The type checker error-stack element `GHC.Tc.Types.ErrCtxt.HsCtxt` + just stores an error message - just stores an error message + type ErrCtxt = HsCtxt When called on an `XExpr`, `addLExprCtxt`, adds the user written thing `ue`, and the error message provided by the caller on the `ErrCtxtStack` See @@ -857,10 +858,9 @@ The rest of this Note explains how that is done. tcHsExpansion :: HsExpansion GhcRn -> ExpRhoType -> TcM (HsExpr GhcTc) tcHsExpansion (HSE o e) res_ty - = mkExpandedTc o <$> -- necessary for hpc ticks - -- Need to call tcExpr and not tcApp - -- as e can be let statement which tcApp cannot gracefully handle - tcMonoLExpr e res_ty + = do e' <- tcMonoLExpr e res_ty + return $ XExpr (HSE o e') + {- ************************************************************************ View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/8b3ded23eeab94cfbef7ea6e59868b4… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/8b3ded23eeab94cfbef7ea6e59868b4… You're receiving this email because of your account on gitlab.haskell.org.

1 0

[Git][ghc/ghc][wip/spj-apporv-Oct24] 2 commits: accept callstack001 testcase
by Apoorv Ingle (＠ani) 21 Mar '26

21 Mar '26

Apoorv Ingle pushed to branch wip/spj-apporv-Oct24 at Glasgow Haskell Compiler / GHC Commits: 9cce15d0 by Apoorv Ingle at 2026-03-20T12:26:42-05:00 accept callstack001 testcase - - - - - 46d715bf by Apoorv Ingle at 2026-03-20T12:27:15-05:00 update Note to include HsExpansion - - - - - 2 changed files: - compiler/GHC/Tc/Gen/Expr.hs - testsuite/tests/profiling/should_run/callstack001.stdout Changes: ===================================== compiler/GHC/Tc/Gen/Expr.hs ===================================== @@ -572,7 +572,8 @@ tcExpr (HsDo _ do_or_lc stmts) res_ty = do hse <- expandDoStmts do_or_lc stmts tcHsExpansion hse res_ty | otherwise - -- ListComp, MonadComp are handled by tcDoStmts + -- ListComp and MonadComp are handled by legacy tcDoStmts for now, + -- The ultimate goal is to handle them via expandDoStmts. -- GHCiStmts are handled completely separate = tcDoStmts do_or_lc stmts res_ty @@ -786,15 +787,16 @@ directly, it's much easier to * Expand (or desugar) the code to something simpler * Typecheck that simpler expression -Example: record updates. The typechecker looks like this: +Example: Typechecking the do expression. The typechecker looks (somewhat) like this: - tcExpr e@(HsDo{}) rho = do { ee <- expandExpr e - ; tcExpr ee rho } + tcExpr e@(HsDo _ stmts) rho = do { hse <- expandDoStmts stmts + ; tcHsExpansion hse rho } -The `expandExpr` replaces the HsDo { x <- e1; return x } +The `expandDoStmts` replaces the HsDo { x <- e1; return x } with something like - e1 >>= \ x -> x -and we then typecheck the latter. + HSE { hs_ctxt = e + , expanded_expr = e1 >>= \ x -> x } +and we then typecheck the expression `e1 >>= \ x -> x` See also Note [Handling overloaded and rebindable constructs] and Note [Doing XXExprGhcRn in the Renamer vs Typechecker] @@ -806,8 +808,8 @@ The rest of this Note explains how that is done. * The expansion process typically takes a user written thing L lspan ue and returns - L lspan (XExpr (ExpandedThingRn { xrn_orig = ue - , xrn_expanded = ee } )) + L lspan (XExpr (ExpandedThingRn (HSE { hs_ctxt = ue + , expanded_expr = ee } )) where `ee` is the expansion of the user written thing `ue` * The type checker context has 3 key fields that describe the context: @@ -824,30 +826,29 @@ The rest of this Note explains how that is done. The `tcl_in_gen_code` is a boolean that keeps track of whether the current expression being typechecked is compiler generated or user generated. + INVARIANT: `tcl_in_gen_code` is modified only in `setSrcSpan`. - The `tcl_in_gen_code` is a boolean that keeps track of whether - the current expression being typechecked is compiler generated - or user generated. * Now, when tcMonoLExpr :: LHsExpr GhcRn -> ExpRhoType -> TcM (HsExpr GhcTc) gets a located expression, it does 2 things: - * Calls `addLExprCtxt` to perform error context management - * Calls `tcExpr` to typecheck the expression. + (a) Calls `addLExprCtxt` to perform error context management + (b) Calls `tcExpr` to typecheck the expression. -* `addLExprCtxt span expr` +(a) `addLExprCtxt span expr` (1) updates the location of `tcl_loc` with the `span` above, (2) adds an `ErrCtxt` on top of the `tcl_err_ctxt`. * However, if the `span` is generated (see `isGeneratedSrcSpan`), then - `addLExprCtxt` is a no-op. Crucially, when we generate code in `expandExpr`, + `addLExprCtxt` sets `tcl_in_gen_code` to `True` via a call to `setSrcSpan` + and the `tcl_err_ctxt` is left untouched. Crucially, when we generate code in `expandExpr`, all the generated AST notes are tagged with a `GeneratedSrcSpan`. This is how we avoid populating the TcLclCtxt with generated code. -* The type checker error-stack element `GHC.Tc.Types.ErrCtxt.ErrCtxt` - type ErrCtxt = HsCtxt +* The type checker error-stack element `GHC.Tc.Types.ErrCtxt.HsCtxt` + just stores an error message - just stores an error message + type ErrCtxt = HsCtxt When called on an `XExpr`, `addLExprCtxt`, adds the user written thing `ue`, and the error message provided by the caller on the `ErrCtxtStack` See @@ -857,10 +858,9 @@ The rest of this Note explains how that is done. tcHsExpansion :: HsExpansion GhcRn -> ExpRhoType -> TcM (HsExpr GhcTc) tcHsExpansion (HSE o e) res_ty - = mkExpandedTc o <$> -- necessary for hpc ticks - -- Need to call tcExpr and not tcApp - -- as e can be let statement which tcApp cannot gracefully handle - tcMonoLExpr e res_ty + = do e' <- tcMonoLExpr e res_ty + return $ XExpr HSE o e' + {- ************************************************************************ ===================================== testsuite/tests/profiling/should_run/callstack001.stdout ===================================== @@ -1,2 +1,2 @@ -["GHC.Internal.TopHandler.runMainIO1 (<no location info>)","Main.main (callstack001.hs:17:8-21)","Main.mapM (callstack001.hs:10:13-17)","Main.mapM.go (callstack001.hs:(12,21)-(15,25))","Main.mapM.go (callstack001.hs:13:17-19)","Main.f (callstack001.hs:7:7-49)","Main.f (callstack001.hs:7:10-35)","GHC.Internal.Base.>>= (libraries/ghc-internal/src/GHC/Internal/Base.hs:1347:5-55)","GHC.Internal.Base.$fMonadIO1 (<no location info>)","GHC.Internal.Stack.CCS.currentCallStack (libraries/ghc-internal/src/GHC/Internal/Stack/CCS.hsc:129:1-16)","GHC.Internal.Stack.CCS.currentCallStack1 (<no location info>)"] -["GHC.Internal.TopHandler.runMainIO1 (<no location info>)","Main.main (callstack001.hs:17:8-21)","Main.mapM (callstack001.hs:10:13-17)","Main.mapM.go (callstack001.hs:(12,21)-(15,25))","GHC.Internal.Base.>>= (libraries/ghc-internal/src/GHC/Internal/Base.hs:1347:5-55)","GHC.Internal.Base.$fMonadIO1 (<no location info>)","GHC.Internal.Stack.CCS.currentCallStack (libraries/ghc-internal/src/GHC/Internal/Stack/CCS.hsc:129:1-16)","GHC.Internal.Stack.CCS.currentCallStack1 (<no location info>)"] +["GHC.Internal.TopHandler.runMainIO1 (<no location info>)","Main.main (callstack001.hs:17:8-21)","Main.mapM (callstack001.hs:10:13-17)","Main.mapM.go (callstack001.hs:(12,21)-(15,25))","Main.mapM.go (callstack001.hs:13:11-19)","Main.mapM.go (callstack001.hs:13:17-19)","Main.f (callstack001.hs:7:7-49)","Main.f (callstack001.hs:7:10-35)","GHC.Internal.Base.>>= (libraries/ghc-internal/src/GHC/Internal/Base.hs:1347:5-55)","GHC.Internal.Base.$fMonadIO1 (<no location info>)","GHC.Internal.Stack.CCS.currentCallStack (libraries/ghc-internal/src/GHC/Internal/Stack/CCS.hsc:129:1-16)","GHC.Internal.Stack.CCS.currentCallStack1 (<no location info>)"] +["GHC.Internal.TopHandler.runMainIO1 (<no location info>)","Main.main (callstack001.hs:17:8-21)","Main.mapM (callstack001.hs:10:13-17)","Main.mapM.go (callstack001.hs:(12,21)-(15,25))","Main.mapM.go (callstack001.hs:13:11-19)","GHC.Internal.Base.>>= (libraries/ghc-internal/src/GHC/Internal/Base.hs:1347:5-55)","GHC.Internal.Base.$fMonadIO1 (<no location info>)","GHC.Internal.Stack.CCS.currentCallStack (libraries/ghc-internal/src/GHC/Internal/Stack/CCS.hsc:129:1-16)","GHC.Internal.Stack.CCS.currentCallStack1 (<no location info>)"] \ No newline at end of file View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/7d2a15c1226cfa12c0df3b011d91d7… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/7d2a15c1226cfa12c0df3b011d91d7… You're receiving this email because of your account on gitlab.haskell.org.

1 0