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[Git][ghc/ghc][wip/ani/better-expansion] Move tcExpand to a new file
by Simon Peyton Jones (＠simonpj) 01 Apr '26

01 Apr '26

Simon Peyton Jones pushed to branch wip/ani/better-expansion at Glasgow Haskell Compiler / GHC Commits: 10f21fa6 by Simon Peyton Jones at 2026-03-31T21:50:22+01:00 Move tcExpand to a new file Also tidy up mk_origin - - - - - 6 changed files: - compiler/GHC/Tc/Gen/App.hs - + compiler/GHC/Tc/Gen/Expand.hs - compiler/GHC/Tc/Gen/Expr.hs - compiler/GHC/Tc/Gen/Expr.hs-boot - compiler/GHC/Tc/Gen/Head.hs - compiler/ghc.cabal.in Changes: ===================================== compiler/GHC/Tc/Gen/App.hs ===================================== @@ -656,8 +656,8 @@ tcInstFun :: QLFlag -> TcSigmaType -> [HsExprArg 'TcpRn] -> TcM ( [HsExprArg 'TcpInst] , TcSigmaType ) -- Does not instantiate trailing invisible foralls --- This crucial function implements the |-inst judgement in Fig 4, plus the --- modification in Fig 5, of the QL paper: +-- This crucial function implements the |-inst judgement in Fig 4, +-- plus the modification in Fig 5, of the QL paper: -- "A quick look at impredicativity" (ICFP'20). tcInstFun do_ql inst_final rn_head@(_, fun_lspan) tc_fun fun_sigma rn_args = do { traceTc "tcInstFun" (vcat [ text "tc_fun" <+> ppr tc_fun @@ -665,7 +665,8 @@ tcInstFun do_ql inst_final rn_head@(_, fun_lspan) tc_fun fun_sigma rn_args , text "fun_sigma" <+> ppr fun_sigma , text "args:" <+> ppr rn_args , text "do_ql" <+> ppr do_ql]) - ; res@(_, fun_ty) <- go 1 [] fun_sigma rn_args + ; fun_origin <- mk_origin rn_head + ; res@(_, fun_ty) <- go fun_origin 1 [] fun_sigma rn_args ; traceTc "tcInstFun:ret" (ppr fun_ty) ; return res } @@ -683,7 +684,7 @@ tcInstFun do_ql inst_final rn_head@(_, fun_lspan) tc_fun fun_sigma rn_args = return $ exprCtOrigin rn_fun | otherwise -- If the location is generated, the best we can do is to - -- approximate by looking on top of the error message stack + -- approximate by looking on top of the error message stack = do { err_ctxt_stack <- getErrCtxt ; let hs_ctxt = case err_ctxt_stack of (c:_) -> c @@ -692,8 +693,6 @@ tcInstFun do_ql inst_final rn_head@(_, fun_lspan) tc_fun fun_sigma rn_args ; return $ hsCtxtCtOrigin hs_ctxt } - - -- These are the type variables which must be instantiated to concrete -- types. See Note [Representation-polymorphic Ids with no binding] -- in GHC.Tc.Utils.Concrete @@ -725,34 +724,35 @@ tcInstFun do_ql inst_final rn_head@(_, fun_lspan) tc_fun fun_sigma rn_args inst_fun _ = isInferredForAllTyFlag ----------- - go, go1 :: Int -- Value-argument position of next arg + go, go1 :: CtOrigin -- Of the function + -> Int -- Value-argument position of next arg -> [HsExprArg 'TcpInst] -- Accumulator, reversed -> TcSigmaType -> [HsExprArg 'TcpRn] -> TcM ([HsExprArg 'TcpInst], TcSigmaType) -- go: If fun_ty=kappa, look it up in Theta - go pos acc fun_ty args + go fun_orig pos acc fun_ty args | Just kappa <- getTyVar_maybe fun_ty , isQLInstTyVar kappa = do { cts <- readMetaTyVar kappa ; case cts of - Indirect fun_ty' -> go pos acc fun_ty' args - Flexi -> go1 pos acc fun_ty args } + Indirect fun_ty' -> go fun_orig pos acc fun_ty' args + Flexi -> go1 fun_orig pos acc fun_ty args } | otherwise - = go1 pos acc fun_ty args + = go1 fun_orig pos acc fun_ty args -- go1: fun_ty is not filled-in instantiation variable -- ('go' dealt with that case) -- Handle out-of-scope functions gracefully - go1 pos acc fun_ty (arg : rest_args) + go1 fun_orig pos acc fun_ty (arg : rest_args) | fun_is_out_of_scope, looks_like_type_arg arg -- See Note [VTA for out-of-scope functions] - = go pos acc fun_ty rest_args + = go fun_orig pos acc fun_ty rest_args -- Rule IALL from Fig 4 of the QL paper; applies even if args = [] -- Instantiate invisible foralls and dictionaries. -- c.f. GHC.Tc.Utils.Instantiate.topInstantiate - go1 pos acc fun_ty args + go1 fun_orig pos acc fun_ty args | (tvs, body1) <- tcSplitSomeForAllTyVars (inst_fun args) fun_ty , (theta, body2) <- if inst_fun args Inferred then tcSplitPhiTy body1 @@ -763,8 +763,7 @@ tcInstFun do_ql inst_final rn_head@(_, fun_lspan) tc_fun fun_sigma rn_args , let no_tvs = null tvs no_theta = null theta , not (no_tvs && no_theta) - = do { fun_orig <- mk_origin rn_head - ; (wrap, fun_rho) <- + = do { (wrap, fun_rho) <- -- addHeadCtxt: important for the class constraints -- that may be emitted from instantiating fun_sigma setSrcSpan fun_lspan $ @@ -782,12 +781,12 @@ tcInstFun do_ql inst_final rn_head@(_, fun_lspan) tc_fun fun_sigma rn_args -- argument of (#,#) to @LiftedRep, but want to rule out the -- second instantiation @r. - ; go pos (addArgWrap wrap acc) fun_rho args } + ; go fun_orig pos (addArgWrap wrap acc) fun_rho args } -- Going around again means we deal easily with -- nested forall a. Eq a => forall b. Show b => blah -- Rule IRESULT from Fig 4 of the QL paper; no more arguments - go1 _pos acc fun_ty [] + go1 _fun_orig _pos acc fun_ty [] | XExpr (ConLikeTc (RealDataCon dc)) <- tc_fun , isNewDataCon dc , [Scaled _ orig_arg_ty] <- dataConOrigArgTys dc @@ -807,30 +806,30 @@ tcInstFun do_ql inst_final rn_head@(_, fun_lspan) tc_fun fun_sigma rn_args = return (reverse acc, fun_ty) -- Rule ITVDQ from the GHC Proposal #281 - go1 pos acc fun_ty ((EValArg { ea_arg = arg }) : rest_args) + go1 fun_orig pos acc fun_ty ((EValArg { ea_arg = arg }) : rest_args) | Just (tvb, body) <- tcSplitForAllTyVarBinder_maybe fun_ty = assertPpr (binderFlag tvb == Required) (ppr fun_ty $$ ppr arg) $ -- Any invisible binders have been instantiated by IALL above, -- so this forall must be visible (i.e. Required) do { (ty_arg, inst_body) <- tcVDQ fun_conc_tvs (tvb, body) arg ; let wrap = mkWpTyApps [ty_arg] - ; go (pos+1) (addArgWrap wrap acc) inst_body rest_args } + ; go fun_orig (pos+1) (addArgWrap wrap acc) inst_body rest_args } - go1 pos acc fun_ty (EWrap w : args) - = go1 pos (EWrap w : acc) fun_ty args + go1 fun_orig pos acc fun_ty (EWrap w : args) + = go1 fun_orig pos (EWrap w : acc) fun_ty args - go1 pos acc fun_ty (EPrag sp prag : args) - = go1 pos (EPrag sp prag : acc) fun_ty args + go1 fun_orig pos acc fun_ty (EPrag sp prag : args) + = go1 fun_orig pos (EPrag sp prag : acc) fun_ty args -- Rule ITYARG from Fig 4 of the QL paper - go1 pos acc fun_ty ( ETypeArg { ea_loc_span = ctxt, ea_hs_ty = hs_ty } - : rest_args ) + go1 fun_orig pos acc fun_ty ( ETypeArg { ea_loc_span = ctxt, ea_hs_ty = hs_ty } + : rest_args ) = do { (ty_arg, inst_ty) <- tcVTA fun_conc_tvs fun_ty hs_ty ; let arg' = ETypeArg { ea_loc_span = ctxt, ea_hs_ty = hs_ty, ea_ty_arg = ty_arg } - ; go pos (arg' : acc) inst_ty rest_args } + ; go fun_orig pos (arg' : acc) inst_ty rest_args } -- Rule IVAR from Fig 4 of the QL paper: - go1 pos acc fun_ty args@(EValArg {} : _) + go1 fun_orig pos acc fun_ty args@(EValArg {} : _) | Just kappa <- getTyVar_maybe fun_ty , isQLInstTyVar kappa = -- Function type was of form f :: forall a b. t1 -> t2 -> b @@ -846,7 +845,7 @@ tcInstFun do_ql inst_final rn_head@(_, fun_lspan) tc_fun fun_sigma rn_args -- - We must be sure to actually update the variable right now, -- not defer in any way, because this is a QL instantiation variable. -- It's easier just to do the job directly here. - do { arg_tys <- zipWithM new_arg_ty (leadingValArgs args) [pos..] + do { arg_tys <- zipWithM (new_arg_ty fun_orig) (leadingValArgs args) [pos..] ; res_ty <- newOpenFlexiTyVarTyQL do_ql TauTv ; let fun_ty' = mkScaledFunTys arg_tys res_ty @@ -862,13 +861,12 @@ tcInstFun do_ql inst_final rn_head@(_, fun_lspan) tc_fun fun_sigma rn_args -- Then fun_ty :: kk, fun_ty' :: Type, kind_co :: Type ~ kk -- co_wrap :: (fun_ty' |> kind_co) ~ fun_ty' - ; go pos acc' fun_ty' args } + ; go fun_orig pos acc' fun_ty' args } -- Rule IARG from Fig 4 of the QL paper: - go1 pos acc fun_ty + go1 fun_orig pos acc fun_ty (EValArg { ea_arg = arg, ea_loc_span = ctxt } : rest_args) - = do { fun_orig <- mk_origin rn_head - ; let herald = mk_herald fun_orig tc_fun (unLoc arg) + = do { let herald = mk_herald fun_orig tc_fun (unLoc arg) ; (fun_co, arg_ty, res_ty) <- -- NB: matchActualFunTy does the rep-poly check. -- For example, suppose we have f :: forall r (a::TYPE r). a -> Int @@ -882,13 +880,12 @@ tcInstFun do_ql inst_final rn_head@(_, fun_lspan) tc_fun fun_sigma rn_args (n_val_args, fun_sigma) fun_ty ; arg' <- quickLookArg do_ql pos ctxt rn_head arg arg_ty ; let acc' = arg' : addArgWrap (mkWpCastN fun_co) acc - ; go (pos+1) acc' res_ty rest_args } + ; go fun_orig (pos+1) acc' res_ty rest_args } - new_arg_ty :: LHsExpr GhcRn -> Int -> TcM (Scaled TcType) + new_arg_ty :: CtOrigin -> LHsExpr GhcRn -> Int -> TcM (Scaled TcType) -- Make a fresh nus for each argument in rule IVAR - new_arg_ty (L _ arg) i - = do { fun_orig <- mk_origin rn_head - ; arg_nu <- newArgTyVarTyQL do_ql $ + new_arg_ty fun_orig (L _ arg) i + = do { arg_nu <- newArgTyVarTyQL do_ql $ FRRExpectedFunTy (mk_herald fun_orig tc_fun arg) i -- Following matchActualFunTy, we create nu_i :: TYPE kappa_i[conc], -- thereby ensuring that the arguments have concrete runtime representations ===================================== compiler/GHC/Tc/Gen/Expand.hs ===================================== @@ -0,0 +1,118 @@ +{-# LANGUAGE TypeFamilies #-} + +{- +(c) The University of Glasgow 2006 +(c) The GRASP/AQUA Project, Glasgow University, 1992-1998 +-} + +module GHC.Tc.Gen.Expand( tcExpand ) where + +import GHC.Prelude + +import {-# SOURCE #-} GHC.Tc.Gen.Splice( getUntypedSpliceBody ) + +import GHC.Hs + +import GHC.Tc.Utils.Monad +import GHC.Tc.Types.ErrCtxt + +import GHC.Rename.Utils + +import GHC.Types.SrcLoc + + +{- Note [Typechecking by expansion: overview] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +For many constructs, rather than typechecking the user-written code +directly, it's much easier to + * Expand (or desugar) the code to something simpler + * Typecheck that simpler expression + +Example: Typechecking the do expression. The typechecker looks (somewhat) like this: + + tcExpr e@(HsDo _ stmts) rho = do { hse <- expandDoStmts stmts + ; tcHsExpansion hse rho } + +The `expandDoStmts` replaces the HsDo { x <- e1; return x } +with something like + HSE { hse_ctxt = ExprCtxt e + , hse_exp = 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] + +The Big Question is how to ensure that error messages mention +only user-written source code, and never talk about the expanded code. +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 (HSE { hse_ctxt = ue + , hse_exp = ee } )) + where `ee` is the expansion of the user written thing `ue` + +* The type checker context has 3 key fields that describe the context: + TcLclCtxt { tcl_loc :: RealSrcSpan + , tcl_in_gen_code :: Bool + , tcl_err_ctxt :: ErrCtxtStack + , ... } + Note `tcl_loc` always points to a real place in the source code, + hence `RealSrcSpan`. + + The `tcl_err_ctxt` is a stack of contexts, each saying something + like "In the expression: x+y" or "In second argument of `$` namely 'r { x=2 }'" + + 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_loc` and `tcl_in_gen_code` are modified only in `setSrcSpan`. + +* Now, when + tcMonoLExpr :: LHsExpr GhcRn -> ExpRhoType -> TcM (HsExpr GhcTc) + gets a located expression, it does 3 things: + (a) Calls `setSrcSpanA` to set the ambient source-code location + (b) Calls `addExprCtxt` to push a suitable `HsCtxt` on top of the `tcl_err_ctxt`. + (c) Calls `tcExpr` to typecheck the expression. + +* In these calls, if the `span` is generated (see `isGeneratedSrcSpan`), then + - `setSrcSpanA` sets `tcl_in_gen_code` to `True`, and leaves `tcl_loc` unchanged + - `addExprCtxt` is a no-op if `tcl_in_gen_code` is True + The result is that `tcl_loc` has the span from the innermost /user/ tree node; + and the ErrCtxtStack in `tcl_err_ctxt` only has contexts arisign from user code. + +* Note that inside an expansion we have sub-expressions from the original program. + As soon as we enter one of those, identified by a /user/ span, `setSrcSpanA` will + sets the `tcl_loc` to reflect that span, and switch off `tcl_in_gen_code`. Nice! +-} + +--------------- +tcExpand :: HsExpr GhcRn -> TcM (Maybe (HsExpansion GhcRn)) +tcExpand e@(OpApp _ arg1 op arg2) + = return $ Just $ + HSE { hse_ctxt = ExprCtxt e + , hse_exp = foldl ap op [arg1,arg2] } + where + ap f a = wrapGenSpan (HsApp noExtField f a) + +tcExpand (XExpr (ExpandedThingRn hse)) + = return (Just hse) + +tcExpand e@(HsUntypedSplice splice_res _) +-- See Note [Looking through Template Haskell splices in splitHsApps] + = do { fun <- getUntypedSpliceBody splice_res + ; return $ Just $ + HSE { hse_ctxt = ExprCtxt e -- ToDo: right? + , hse_exp = L noSrcSpanA fun } } -- Span? +{- + where + lspan' :: SrcSpan + lspan' = case splice of + HsUntypedSpliceExpr _ (L l _) -> locA l -- l :: SrcAnn AnnListItem + HsQuasiQuote _ _ (L l _) -> locA l -- l :: SrcAnn NoEpAnns + (XUntypedSplice (HsImplicitLiftSplice _ _ _ (L l _))) -> locA l +-} + +tcExpand _ = return Nothing ===================================== compiler/GHC/Tc/Gen/Expr.hs ===================================== @@ -19,7 +19,6 @@ module GHC.Tc.Gen.Expr tcInferRhoFRR, tcInferRhoFRRNC, tcPolyLExpr, tcPolyLExprSig, tcPolyLExprNC, tcPolyExpr, tcExpr, - tcExpand, tcSyntaxOp, tcSyntaxOpGen, SyntaxOpType(..), synKnownType, tcCheckId, ) where @@ -31,10 +30,10 @@ import {-# SOURCE #-} GHC.Tc.Gen.Splice import GHC.Hs import GHC.Hs.Syn.Type - import GHC.Rename.Utils import GHC.Rename.Env ( addUsedGRE, getUpdFieldLbls ) +import GHC.Tc.Gen.Expand( tcExpand ) import GHC.Tc.Gen.App import GHC.Tc.Gen.Head import GHC.Tc.Gen.Do @@ -770,73 +769,6 @@ tcExpr e res_ty ************************************************************************ -} -{- Note [Typechecking by expansion: overview] -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -For many constructs, rather than typechecking the user-written code -directly, it's much easier to - * Expand (or desugar) the code to something simpler - * Typecheck that simpler expression - -Example: Typechecking the do expression. The typechecker looks (somewhat) like this: - - tcExpr e@(HsDo _ stmts) rho = do { hse <- expandDoStmts stmts - ; tcHsExpansion hse rho } - -The `expandDoStmts` replaces the HsDo { x <- e1; return x } -with something like - HSE { hse_ctxt = ExprCtxt e - , hse_exp = 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] - -The Big Question is how to ensure that error messages mention -only user-written source code, and never talk about the expanded code. -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 (HSE { hse_ctxt = ue - , hse_exp = ee } )) - where `ee` is the expansion of the user written thing `ue` - -* The type checker context has 3 key fields that describe the context: - TcLclCtxt { tcl_loc :: RealSrcSpan - , tcl_in_gen_code :: Bool - , tcl_err_ctxt :: ErrCtxtStack - , ... } - Note `tcl_loc` always points to a real place in the source code, - hence `RealSrcSpan`. - - The `tcl_err_ctxt` is a stack of contexts, each saying something - like "In the expression: x+y" or "In second argument of `$` namely 'r { x=2 }'" - - 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_loc` and `tcl_in_gen_code` are modified only in `setSrcSpan`. - -* Now, when - tcMonoLExpr :: LHsExpr GhcRn -> ExpRhoType -> TcM (HsExpr GhcTc) - gets a located expression, it does 3 things: - (a) Calls `setSrcSpanA` to set the ambient source-code location - (b) Calls `addExprCtxt` to push a suitable `HsCtxt` on top of the `tcl_err_ctxt`. - (c) Calls `tcExpr` to typecheck the expression. - -* In these calls, if the `span` is generated (see `isGeneratedSrcSpan`), then - - `setSrcSpanA` sets `tcl_in_gen_code` to `True`, and leaves `tcl_loc` unchanged - - `addExprCtxt` is a no-op if `tcl_in_gen_code` is True - The result is that `tcl_loc` has the span from the innermost /user/ tree node; - and the ErrCtxtStack in `tcl_err_ctxt` only has contexts arisign from user code. - -* Note that inside an expansion we have sub-expressions from the original program. - As soon as we enter one of those, identified by a /user/ span, `setSrcSpanA` will - sets the `tcl_loc` to reflect that span, and switch off `tcl_in_gen_code`. Nice! --} - tcHsExpansion :: HsExpansion GhcRn -> ExpRhoType -> TcM (HsExpr GhcTc) tcHsExpansion (HSE { hse_ctxt = o, hse_exp = e }) res_ty = do { e' <- tcMonoLExpr e res_ty @@ -844,31 +776,6 @@ tcHsExpansion (HSE { hse_ctxt = o, hse_exp = e }) res_ty HSE { hse_ctxt = o, hse_exp = e' } } ---------------- -tcExpand :: HsExpr GhcRn -> TcM (Maybe (HsExpansion GhcRn)) -tcExpand e@(OpApp _ arg1 op arg2) - = return (Just (HSE { hse_ctxt = ExprCtxt e - , hse_exp = wrapGenSpan (unLoc $ mkHsApps op [arg1,arg2]) })) -tcExpand (XExpr (ExpandedThingRn hse)) - = return (Just hse) - -tcExpand e@(HsUntypedSplice splice_res _) --- See Note [Looking through Template Haskell splices in splitHsApps] - = do { fun <- getUntypedSpliceBody splice_res - ; return $ Just $ - HSE { hse_ctxt = ExprCtxt e -- ToDo: right? - , hse_exp = L noSrcSpanA fun } } -- Span? -{- - where - lspan' :: SrcSpan - lspan' = case splice of - HsUntypedSpliceExpr _ (L l _) -> locA l -- l :: SrcAnn AnnListItem - HsQuasiQuote _ _ (L l _) -> locA l -- l :: SrcAnn NoEpAnns - (XUntypedSplice (HsImplicitLiftSplice _ _ _ (L l _))) -> locA l --} - -tcExpand _ = return Nothing - {- ************************************************************************ * * ===================================== compiler/GHC/Tc/Gen/Expr.hs-boot ===================================== @@ -9,7 +9,6 @@ import GHC.Tc.Types.BasicTypes( TcCompleteSig ) import GHC.Tc.Types.Origin ( CtOrigin, FixedRuntimeRepContext ) import GHC.Core.Type ( Mult ) import GHC.Hs.Extension ( GhcRn, GhcTc ) -import Data.Maybe( Maybe ) tcCheckPolyExpr, tcCheckPolyExprNC :: LHsExpr GhcRn @@ -40,8 +39,6 @@ tcInferExprSigma :: HsExpr GhcRn -> TcM (HsExpr GhcTc, TcSigmaType) tcInferExpr :: InferInstFlag -> LHsExpr GhcRn -> TcM (LHsExpr GhcTc, TcType) -tcExpand :: HsExpr GhcRn -> TcM (Maybe (HsExpansion GhcRn)) - tcSyntaxOp :: CtOrigin -> SyntaxExprRn -> [SyntaxOpType] -- ^ shape of syntax operator arguments ===================================== compiler/GHC/Tc/Gen/Head.hs ===================================== @@ -21,13 +21,14 @@ module GHC.Tc.Gen.Head , pprArgInst, addFunResCtxt ) where -import {-# SOURCE #-} GHC.Tc.Gen.Expr( tcExpr, tcExpand, tcCheckPolyExprNC, tcPolyLExprSig ) +import {-# SOURCE #-} GHC.Tc.Gen.Expr( tcExpr, tcCheckPolyExprNC, tcPolyLExprSig ) import GHC.Prelude import GHC.Hs import GHC.Hs.Syn.Type import GHC.Tc.Gen.HsType +import GHC.Tc.Gen.Expand( tcExpand ) import GHC.Tc.Gen.Bind( chooseInferredQuantifiers ) import GHC.Tc.Gen.Sig( tcUserTypeSig, tcInstSig ) import GHC.Tc.TyCl.PatSyn( patSynBuilderOcc ) ===================================== compiler/ghc.cabal.in ===================================== @@ -832,6 +832,7 @@ Library GHC.Tc.Gen.Bind GHC.Tc.Gen.Default GHC.Tc.Gen.Do + GHC.Tc.Gen.Expand GHC.Tc.Gen.Export GHC.Tc.Gen.Expr GHC.Tc.Gen.Foreign View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/10f21fa6d32a88ff9c7dcd36d357d5d… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/10f21fa6d32a88ff9c7dcd36d357d5d… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][wip/T26831] 12 commits: Bump minimum shake version for hadrian.
by Simon Peyton Jones (＠simonpj) 01 Apr '26

01 Apr '26

Simon Peyton Jones pushed to branch wip/T26831 at Glasgow Haskell Compiler / GHC Commits: d741a6cc by Andreas Klebinger at 2026-03-31T04:39:33-04:00 Bump minimum shake version for hadrian. We also add the shake version we want to stack.yaml Fixes #26884 - - - - - 5e556f9e by Vladislav Zavialov at 2026-03-31T04:40:16-04:00 Status check for the HsType~HsExpr refactoring (#25121) Add a test case to track the status of a refactoring project within GHC whose goal is to arrive at the following declaration: type HsType = HsExpr The rationale for this is to increase code reuse between the term- and type-level code in the compiler front-end (AST, parser, renamer, type checker). The status report is saved to testsuite/tests/ghc-api/T25121_status.stdout and provides useful insights into what needs to happen to make progress on the ticket. - - - - - acffb1b1 by fendor at 2026-03-31T04:41:02-04:00 Extract Binary instances to `GHC.ByteCode.Binary` - - - - - e2ea8e25 by fendor at 2026-03-31T04:41:02-04:00 Add `seqNonEmpty` for evaluating `NonEmpty a` - - - - - 048b00b7 by fendor at 2026-03-31T04:41:02-04:00 Record `LinkableUsage` instead of `Linkable` in `LoaderState` Retaining a ByteCode `Linkable` after it has been loaded retains its `UnlinkedBCO`, keeping it alive for the remainder of the program. This starts accumulating a lot of `UnlinkedBCO` and memory over time. However, the `Linkable` is merely used to later record its usage in `mkObjectUsage`, which is used for recompilation checking. However, this is incorrect, as the interface file and bytecode objects could be in different states, e.g. the interface changes, but the bytecode library hasn't changed so we don't need to recompile and vice versa. By computing a `Fingerprint` for the `ModuleByteCode`, and recording it in the `LinkableUsage`, we know precisely whether the `ByteCode` object on disk is outdated. Thus, parts of this commit just makes sure that we efficiently compute a `Fingerprint` for `ModuleByteCode` and store it in the on-disk representation of `ModuleByteCode`. We change the `LoaderState` to retain `LinkableUsage`, which is smaller representation of a `Linkable`. This allows us to free the unneeded fields of `Linkable` after linking them. We declare the following memory invariants that this commit implements: * No `LinkablePart` should be retained from `LoaderState`. * `Linkable`s should be unloaded after they have been loaded. These invariants are unfortunately tricky to automatically uphold, so we are simply documenting our assumptions for now. We introduce the `linkable-space` test which makes sure that after loading, no `DotGBC` or `UnlinkedBCO` is retained. ------------------------- Metric Increase: MultiLayerModulesTH_OneShot ------------------------- We allocate a bit more, but the peak number of bytes doesn't change. While a bit unfortunate, accepting the metric increase. We add multiple new performance measurements where we were able to observe the desired memory invariants. Further, we add regression tests to validate that the recompilation checker behaves more correct than before. - - - - - 2d1c1997 by Simon Jakobi at 2026-03-31T04:41:46-04:00 Eliminate dictionary-passing in ListMap operations Mark the ListMap helpers 'INLINABLE' so importing modules can specialise the 'TrieMap (ListMap m)' methods and avoid recursive dictionary-passing. See Note [Making ListMap operations specialisable]. Fixes #27097 - - - - - ed2c6570 by Cheng Shao at 2026-03-31T04:42:33-04:00 testsuite: fix testdir cleanup logic on Windows testdir cleanup is unreliable on Windows (#13162) and despite existing hacks in the driver, new failure mode has occurred. This patch makes it print the warning and carry on when failed to clean up a testdir, instead of reporting a spurious framework failure. See added comment for detailed explanation. - - - - - d9388e29 by Simon Jakobi at 2026-03-31T13:14:59-04:00 Add regression test for #18177 Closes #18177. Assisted-by: Codex - - - - - 6a10045c by mangoiv at 2026-03-31T13:15:43-04:00 ci: allow metric decrease for two tests on i386 There has been a nightly failure on i386 due to a compiler runtime improvement on i386 debian 12. We allow that. Metric Decrease (test_env='i386-linux-deb12'): T12707 T8095 - - - - - e9623c94 by Simon Peyton Jones at 2026-03-31T21:01:01+01:00 Refactor eta-expansion in Prep The Prep pass does eta-expansion but I found cases where it was doing bad things. So I refactored and simplified it quite a bit. In the new design * There is no distinction between `rhs` and `body`; in particular, lambdas can now appear anywhere, rather than just as the RHS of a let-binding. * This change led to a significant simplification of Prep, and a more straightforward explanation of eta-expansion. See the new Note [Eta expansion] * The consequences is that CoreToStg needs to handle naked lambdas. This is very easy; but it does need a unique supply, which forces some simple refactoring. Having a unique supply to hand is probably a good thing anyway. - - - - - 3a33983b by Simon Peyton Jones at 2026-03-31T21:01:02+01:00 Clarify Note [Interesting dictionary arguments] Ticket #26831 ended up concluding that the code for GHC.Core.Opt.Specialise.interestingDict was good, but the commments were a bit inadequate. This commit improves the comments slightly. - - - - - 690acec9 by Simon Peyton Jones at 2026-03-31T21:01:02+01:00 Make inlining a bit more eager for overloaded functions If we have f d = ... (class-op d x y) ... we should be eager to inline `f`, because that may change the higher order call (class-op d x y) into a call to a statically known function. See the discussion on #26831. Even though this does a bit /more/ inlining, compile times decrease by an average of 0.4%. Compile time changes: DsIncompleteRecSel3(normal) 431,786,104 -2.2% ManyAlternatives(normal) 670,883,768 -1.6% ManyConstructors(normal) 3,758,493,832 -2.6% GOOD MultilineStringsPerf(normal) 29,900,576 -2.8% T14052Type(ghci) 1,047,600,848 -1.2% T17836(normal) 392,852,328 -5.2% T18478(normal) 442,785,768 -1.4% T21839c(normal) 341,536,992 -14.1% GOOD T3064(normal) 174,086,152 +5.3% BAD T5631(normal) 506,867,800 +1.0% hard_hole_fits(normal) 209,530,736 -1.3% info_table_map_perf(normal) 19,523,093,184 -1.2% parsing001(normal) 377,810,528 -1.1% pmcOrPats(normal) 60,075,264 -0.5% geo. mean -0.4% minimum -14.1% maximum +5.3% Runtime changes haddock.Cabal(normal) 27,351,988,792 -0.7% haddock.base(normal) 26,997,212,560 -0.6% haddock.compiler(normal) 219,531,332,960 -1.0% Metric Decrease: ManyConstructors T17949 T21839c T13035 TcPlugin_RewritePerf hard_hole_fits Metric Increase: T3064 - - - - - 69 changed files: - compiler/GHC/Builtin/PrimOps.hs - + compiler/GHC/ByteCode/Binary.hs - + compiler/GHC/ByteCode/Recomp/Binary.hs - compiler/GHC/ByteCode/Serialize.hs - compiler/GHC/Core/Opt/Arity.hs - compiler/GHC/Core/Opt/Specialise.hs - compiler/GHC/Core/Tidy.hs - compiler/GHC/Core/Unfold.hs - compiler/GHC/CoreToStg.hs - compiler/GHC/CoreToStg/Prep.hs - compiler/GHC/Data/TrieMap.hs - compiler/GHC/Driver/Hooks.hs - compiler/GHC/Driver/Main.hs - compiler/GHC/Driver/Pipeline.hs - compiler/GHC/Driver/Plugins.hs - compiler/GHC/HsToCore/Usage.hs - compiler/GHC/Iface/Recomp.hs - compiler/GHC/Iface/Recomp/Types.hs - compiler/GHC/Linker/ByteCode.hs - compiler/GHC/Linker/Deps.hs - compiler/GHC/Linker/Loader.hs - compiler/GHC/Linker/Types.hs - compiler/GHC/Runtime/Loader.hs - compiler/GHC/Stg/Lint.hs - compiler/GHC/Tc/Types.hs - compiler/GHC/Tc/Utils/Monad.hs - compiler/GHC/Types/Id.hs - compiler/GHC/Types/Id/Info.hs - compiler/GHC/Unit/Home/ModInfo.hs - compiler/GHC/Unit/Module/Deps.hs - compiler/GHC/Unit/Module/Status.hs - compiler/GHC/Utils/Misc.hs - compiler/ghc.cabal.in - ghc/GHCi/Leak.hs - hadrian/hadrian.cabal - hadrian/stack.yaml - testsuite/driver/testlib.py - testsuite/tests/arityanal/should_compile/Arity01.stderr - testsuite/tests/arityanal/should_compile/Arity05.stderr - testsuite/tests/arityanal/should_compile/Arity08.stderr - testsuite/tests/arityanal/should_compile/Arity11.stderr - testsuite/tests/arityanal/should_compile/Arity14.stderr - + testsuite/tests/bytecode/TLinkable/BCOTemplate.hs - + testsuite/tests/bytecode/TLinkable/LinkableUsage01.stderr - + testsuite/tests/bytecode/TLinkable/LinkableUsage02.stderr - + testsuite/tests/bytecode/TLinkable/Makefile - + testsuite/tests/bytecode/TLinkable/all.T - + testsuite/tests/bytecode/TLinkable/genLinkables.sh - + testsuite/tests/bytecode/TLinkable/linkable-space.hs - + testsuite/tests/bytecode/TLinkable/linkable-space.stdout - testsuite/tests/count-deps/CountDepsAst.stdout - testsuite/tests/count-deps/CountDepsParser.stdout - + testsuite/tests/driver/T18177.hs - testsuite/tests/driver/all.T - testsuite/tests/driver/multipleHomeUnits/multipleHomeUnits_recomp_th.stdout - + testsuite/tests/driver/recomp022/A1.hs - + testsuite/tests/driver/recomp022/A2.hs - + testsuite/tests/driver/recomp022/A3.hs - + testsuite/tests/driver/recomp022/B.hs - + testsuite/tests/driver/recomp022/C.hs - + testsuite/tests/driver/recomp022/Makefile - + testsuite/tests/driver/recomp022/all.T - + testsuite/tests/driver/recomp022/recomp022a.stdout - + testsuite/tests/driver/recomp022/recomp022b.stdout - + testsuite/tests/ghc-api/T25121_status.hs - + testsuite/tests/ghc-api/T25121_status.stdout - testsuite/tests/ghc-api/all.T - testsuite/tests/simplCore/should_compile/T15205.stderr - testsuite/tests/wasm/should_run/control-flow/LoadCmmGroup.hs The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/1cd8fe23fc127adacca091b5e46c7b… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/1cd8fe23fc127adacca091b5e46c7b… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][wip/ani/better-expansion] move mk_origin inside tcInstFun
by Apoorv Ingle (＠ani) 01 Apr '26

01 Apr '26

Apoorv Ingle pushed to branch wip/ani/better-expansion at Glasgow Haskell Compiler / GHC Commits: fac14765 by Apoorv Ingle at 2026-03-31T14:41:18-05:00 move mk_origin inside tcInstFun - - - - - 2 changed files: - compiler/GHC/Tc/Gen/App.hs - compiler/GHC/Tc/Gen/Head.hs Changes: ===================================== compiler/GHC/Tc/Gen/App.hs ===================================== @@ -380,22 +380,12 @@ tcApp rn_expr rn_fun rn_args exp_res_ty -- Step 3.1: Instantiate the function type (taking a quick look at args) ; do_ql <- wantQuickLook rn_fun - -- Setp 3.2 Set the correct origin to blame for the error message - -- What should be the origin for this function call? - -- If the head of the function is user written - -- then it can be used in the error message - -- If it is generated code location span, blame it on the - -- origin that can be retrived from the top of the error ctxt stack. - -- See Note [Error contexts in generated code] - ; fun_orig <- mk_origin fun_lspan rn_fun - ; traceTc "tcApp:inferAppHead" $ vcat [ text "tc_fun:" <+> ppr tc_fun , text "fun_sigma:" <+> ppr fun_sigma - , text "fun_origin" <+> ppr fun_orig , text "do_ql:" <+> ppr do_ql] ; (inst_args, app_res_rho) - <- tcInstFun do_ql inst_final (fun_orig, rn_fun, fun_lspan) tc_fun fun_sigma rn_args + <- tcInstFun do_ql inst_final (rn_fun, fun_lspan) tc_fun fun_sigma rn_args -- See (TCAPP1) and (TCAPP2) in -- Note [tcApp: typechecking applications] @@ -661,7 +651,7 @@ tcInstFun :: QLFlag -- always return a rho-type (but not a deep-rho type) -- Generally speaking we pass in True; in Fig 5 of the paper -- |-inst returns a rho-type - -> (CtOrigin, HsExpr GhcRn, SrcSpan) + -> (HsExpr GhcRn, SrcSpan) -> HsExpr GhcTc -> TcSigmaType -> [HsExprArg 'TcpRn] -> TcM ( [HsExprArg 'TcpInst] @@ -669,18 +659,41 @@ tcInstFun :: QLFlag -- This crucial function implements the |-inst judgement in Fig 4, plus the -- modification in Fig 5, of the QL paper: -- "A quick look at impredicativity" (ICFP'20). -tcInstFun do_ql inst_final (fun_orig, rn_fun, fun_lspan) tc_fun fun_sigma rn_args - = do { traceTc "tcInstFun" (vcat [ text "origin" <+> ppr fun_orig - , text "tc_fun" <+> ppr tc_fun +tcInstFun do_ql inst_final rn_head@(_, fun_lspan) tc_fun fun_sigma rn_args + = do { traceTc "tcInstFun" (vcat [ text "tc_fun" <+> ppr tc_fun + , text "rn_fun" <+> ppr rn_head , text "fun_sigma" <+> ppr fun_sigma , text "args:" <+> ppr rn_args - , text "do_ql" <+> ppr do_ql - , text "ctx" <+> ppr fun_lspan]) + , text "do_ql" <+> ppr do_ql]) ; res@(_, fun_ty) <- go 1 [] fun_sigma rn_args ; traceTc "tcInstFun:ret" (ppr fun_ty) ; return res } where + -- What should be the origin for this function call? + -- If the head of the function is user written + -- then it can be used in the error message + -- If it is generated code location span, blame it on the + -- origin that can be retrived from the top of the error ctxt stack. + -- See Note [Error contexts in generated code] + mk_origin :: (HsExpr GhcRn, SrcSpan) -- The head of the application chain and its location + -> TcM CtOrigin + mk_origin (rn_fun, fun_lspan) + | not (isGeneratedSrcSpan fun_lspan) + = return $ exprCtOrigin rn_fun + + | otherwise -- If the location is generated, the best we can do is to + -- approximate by looking on top of the error message stack + = do { err_ctxt_stack <- getErrCtxt + ; let hs_ctxt = case err_ctxt_stack of + (c:_) -> c + [] -> pprPanic "mk_origin" (ppr rn_fun) + ; traceTc "mk_origin" (pprHsCtxt hs_ctxt) + ; return $ hsCtxtCtOrigin hs_ctxt + } + + + -- These are the type variables which must be instantiated to concrete -- types. See Note [Representation-polymorphic Ids with no binding] -- in GHC.Tc.Utils.Concrete @@ -750,7 +763,8 @@ tcInstFun do_ql inst_final (fun_orig, rn_fun, fun_lspan) tc_fun fun_sigma rn_arg , let no_tvs = null tvs no_theta = null theta , not (no_tvs && no_theta) - = do { (wrap, fun_rho) <- + = do { fun_orig <- mk_origin rn_head + ; (wrap, fun_rho) <- -- addHeadCtxt: important for the class constraints -- that may be emitted from instantiating fun_sigma setSrcSpan fun_lspan $ @@ -853,7 +867,8 @@ tcInstFun do_ql inst_final (fun_orig, rn_fun, fun_lspan) tc_fun fun_sigma rn_arg -- Rule IARG from Fig 4 of the QL paper: go1 pos acc fun_ty (EValArg { ea_arg = arg, ea_loc_span = ctxt } : rest_args) - = do { let herald = mk_herald tc_fun (unLoc arg) + = do { fun_orig <- mk_origin rn_head + ; let herald = mk_herald fun_orig tc_fun (unLoc arg) ; (fun_co, arg_ty, res_ty) <- -- NB: matchActualFunTy does the rep-poly check. -- For example, suppose we have f :: forall r (a::TYPE r). a -> Int @@ -865,15 +880,16 @@ tcInstFun do_ql inst_final (fun_orig, rn_fun, fun_lspan) tc_fun fun_sigma rn_arg matchActualFunTy herald (Just $ HsExprTcThing tc_fun) (n_val_args, fun_sigma) fun_ty - ; arg' <- quickLookArg do_ql pos ctxt (rn_fun, fun_lspan) arg arg_ty + ; arg' <- quickLookArg do_ql pos ctxt rn_head arg arg_ty ; let acc' = arg' : addArgWrap (mkWpCastN fun_co) acc ; go (pos+1) acc' res_ty rest_args } new_arg_ty :: LHsExpr GhcRn -> Int -> TcM (Scaled TcType) -- Make a fresh nus for each argument in rule IVAR new_arg_ty (L _ arg) i - = do { arg_nu <- newArgTyVarTyQL do_ql $ - FRRExpectedFunTy (mk_herald tc_fun arg) i + = do { fun_orig <- mk_origin rn_head + ; arg_nu <- newArgTyVarTyQL do_ql $ + FRRExpectedFunTy (mk_herald fun_orig tc_fun arg) i -- Following matchActualFunTy, we create nu_i :: TYPE kappa_i[conc], -- thereby ensuring that the arguments have concrete runtime representations @@ -883,12 +899,13 @@ tcInstFun do_ql inst_final (fun_orig, rn_fun, fun_lspan) tc_fun fun_sigma rn_arg ; return (mkScaled mult_ty arg_nu) } - mk_herald :: HsExpr GhcTc -> HsExpr GhcRn -> ExpectedFunTyCtxt - mk_herald tc_fun arg + mk_herald :: CtOrigin -> HsExpr GhcTc -> HsExpr GhcRn -> ExpectedFunTyCtxt + mk_herald fun_orig tc_fun arg = case fun_orig of DoStmtOrigin -> ExpectedFunTySyntaxOp DoStmtOrigin tc_fun _ -> ExpectedFunTyArg (HsExprTcThing tc_fun) arg + -- Is the argument supposed to instantiate a forall? -- -- In other words, given a function application `fn arg`, @@ -1959,17 +1976,15 @@ quickLookArg1 pos app_lspan (fun, fun_lspan) larg@(L _ arg) sc_arg_ty@(Scaled _ do { let arg_tc_head = (tc_fun_arg_head, fun_lspan_arg) ; do_ql <- wantQuickLook rn_fun_arg - ; arg_orig <- mk_origin fun_lspan_arg rn_fun_arg ; ((inst_args, app_res_rho), wanted) <- captureConstraints $ - tcInstFun do_ql True (arg_orig, rn_fun_arg, fun_lspan_arg) tc_fun_arg_head fun_sigma_arg_head rn_args + tcInstFun do_ql True (rn_fun_arg, fun_lspan_arg) tc_fun_arg_head fun_sigma_arg_head rn_args -- We must capture type-class and equality constraints here, but -- not usage information. See (QLA6) in Note [Quick Look at -- value arguments] ; traceTc "quickLookArg 2" $ vcat [ text "arg:" <+> ppr arg - , text "orig:" <+> ppr arg_orig , text "orig_arg_rho:" <+> ppr orig_arg_rho , text "app_res_rho:" <+> ppr app_res_rho ] @@ -2007,24 +2022,6 @@ quickLookArg1 pos app_lspan (fun, fun_lspan) larg@(L _ arg) sc_arg_ty@(Scaled _ , eaql_res_rho = app_res_rho }) }}} -mk_origin :: SrcSpan -- SrcSpan of the function - -> HsExpr GhcRn -- The head of the expression application chain - -> TcM CtOrigin -mk_origin fun_lspan rn_fun - | not (isGeneratedSrcSpan fun_lspan) - = return $ exprCtOrigin rn_fun - - | otherwise -- If the location is generated, the best we can do is to - -- approximate by looking on top of the error message stack - = do { err_ctxt_stack <- getErrCtxt - ; let hs_ctxt = case err_ctxt_stack of - (c:_) -> c - [] -> pprPanic "mk_origin" (ppr rn_fun) - ; traceTc "mk_origin" (pprHsCtxt hs_ctxt) - ; return $ hsCtxtCtOrigin hs_ctxt - } - - {- ********************************************************************* * * Folding over instantiation variables ===================================== compiler/GHC/Tc/Gen/Head.hs ===================================== @@ -446,7 +446,7 @@ tcInferAppHead_maybe :: HsExpr GhcRn -- the argument is an XExpr tcInferAppHead_maybe fun = case fun of HsVar _ nm -> Just <$> tcInferId nm - ExprWithTySig _ e hs_ty -> Just <$>tcExprWithSig e hs_ty + ExprWithTySig _ e hs_ty -> Just <$> tcExprWithSig e hs_ty HsOverLit _ lit -> Just <$> tcInferOverLit lit XExpr (HsRecSelRn f) -> Just <$> tcInferRecSelId f _ -> return Nothing View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/fac147656c82853b6476e84a6807284… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/fac147656c82853b6476e84a6807284… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][wip/ani/better-expansion] wrap op apps with generated source span to avoid duplicate error messages
by Apoorv Ingle (＠ani) 01 Apr '26

01 Apr '26

Apoorv Ingle pushed to branch wip/ani/better-expansion at Glasgow Haskell Compiler / GHC Commits: 8a17133d by Apoorv Ingle at 2026-03-31T14:08:09-05:00 wrap op apps with generated source span to avoid duplicate error messages - - - - - 1 changed file: - compiler/GHC/Tc/Gen/Expr.hs Changes: ===================================== compiler/GHC/Tc/Gen/Expr.hs ===================================== @@ -848,7 +848,7 @@ tcHsExpansion (HSE { hse_ctxt = o, hse_exp = e }) res_ty tcExpand :: HsExpr GhcRn -> TcM (Maybe (HsExpansion GhcRn)) tcExpand e@(OpApp _ arg1 op arg2) = return (Just (HSE { hse_ctxt = ExprCtxt e - , hse_exp = mkHsApps op [arg1,arg2] })) + , hse_exp = wrapGenSpan (unLoc $ mkHsApps op [arg1,arg2]) })) tcExpand (XExpr (ExpandedThingRn hse)) = return (Just hse) View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/8a17133dcb55651e8be3e3634bf4d3b… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/8a17133dcb55651e8be3e3634bf4d3b… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][wip/marge_bot_batch_merge_job] 4 commits: Add regression test for #18177
by Marge Bot (＠marge-bot) 01 Apr '26

01 Apr '26

Marge Bot pushed to branch wip/marge_bot_batch_merge_job at Glasgow Haskell Compiler / GHC Commits: d9388e29 by Simon Jakobi at 2026-03-31T13:14:59-04:00 Add regression test for #18177 Closes #18177. Assisted-by: Codex - - - - - 6a10045c by mangoiv at 2026-03-31T13:15:43-04:00 ci: allow metric decrease for two tests on i386 There has been a nightly failure on i386 due to a compiler runtime improvement on i386 debian 12. We allow that. Metric Decrease (test_env='i386-linux-deb12'): T12707 T8095 - - - - - 585e4b4b by Simon Jakobi at 2026-03-31T13:48:54-04:00 Add perf test for #13960 Closes #13960. - - - - - d4a4055f by mangoiv at 2026-03-31T13:48:55-04:00 testsuite: ignore stderr of static001 This reactivates the test on x86_64 darwin as this should have been done long ago and ignores warnings emitted by ranlib on newer version of the darwin toolchain since they are benign. (no symbols for stub libraries) Fixes #27116 - - - - - 5 changed files: - testsuite/driver/testlib.py - + testsuite/tests/driver/T18177.hs - testsuite/tests/driver/all.T - + testsuite/tests/perf/compiler/T13960.hs - testsuite/tests/perf/compiler/all.T Changes: ===================================== testsuite/driver/testlib.py ===================================== @@ -3043,6 +3043,12 @@ def normalise_errmsg(s: str) -> str: # Old emcc warns when we export HEAP8 but new one requires it (see #26290) s = s.replace('warning: invalid item in EXPORTED_RUNTIME_METHODS: HEAP8\nwarning: invalid item in EXPORTED_RUNTIME_METHODS: HEAPU8\nemcc: warning: warnings in JS library compilation [-Wjs-compiler]\n','') + # on newer versions of MacOS X, the shipped ranlib warns about object files with no symbols, + # however, these are completely benign stubs. + # See https://gitlab.haskell.org/ghc/ghc/-/issues/27116 + if opsys('darwin'): + s = re.sub(r'ranlib: warning:.*has no symbols\n', '', s) + return s # normalise a .prof file, so that we can reasonably compare it against ===================================== testsuite/tests/driver/T18177.hs ===================================== @@ -0,0 +1 @@ +module T18177 where ===================================== testsuite/tests/driver/all.T ===================================== @@ -120,9 +120,7 @@ if config.os == 'darwin': else: only_darwin = skip -test('static001', [extra_files(['Static001.hs']), - only_darwin, - when(arch('x86_64'), expect_broken(8127))], +test('static001', [extra_files(['Static001.hs']), only_darwin], makefile_test, ['static001']) test('dynHelloWorld', @@ -314,6 +312,12 @@ test('MultiRootsErr', normal, multimod_compile_fail, ['MultiRootsErr', 'MultiRoo test('patch-level2', normal, compile, ['-Wcpp-undef']) test('T16476a', normal, makefile_test, []) test('T16476b', normal, makefile_test, []) + +# Test that GHC can handle an empty preprocessor response file. +# This used to cause GHC to hang indefinitely: #18177 +test('T18177', [js_skip, pre_cmd('touch cpp-args')], compile, + ['-v0 -fforce-recomp -fhpc -optP@cpp-args -optP-DX']) + test('T20569', extra_files(["T20569/"]), makefile_test, []) test('T21866', normal, multimod_compile, ['T21866','-no-link']) test('T21349', extra_files(['T21349']), makefile_test, []) ===================================== testsuite/tests/perf/compiler/T13960.hs ===================================== @@ -0,0 +1,72 @@ +{-# LANGUAGE OverloadedStrings #-} + +-- GHC used to run out of simplifier ticks due to inlining the internals of +-- `toStrict . toLazyByteString`. +module T13960 (breaks) where + +import Data.ByteString (ByteString) +import Data.ByteString.Builder (Builder, stringUtf8, toLazyByteString) +import Data.ByteString.Lazy (toStrict) +import Data.String (IsString(..)) + +newtype Query = Query ByteString + +toByteString :: Builder -> ByteString +toByteString x = toStrict (toLazyByteString x) + +instance IsString Query where + fromString = Query . toByteString . stringUtf8 + +breaks :: [(Query, Query)] +breaks = + [ ("query001a", "query001b") + , ("query002a", "query002b") + , ("query003a", "query003b") + , ("query004a", "query004b") + , ("query005a", "query005b") + , ("query006a", "query006b") + , ("query007a", "query007b") + , ("query008a", "query008b") + , ("query009a", "query009b") + , ("query010a", "query010b") + , ("query011a", "query011b") + , ("query012a", "query012b") + , ("query013a", "query013b") + , ("query014a", "query014b") + , ("query015a", "query015b") + , ("query016a", "query016b") + , ("query017a", "query017b") + , ("query018a", "query018b") + , ("query019a", "query019b") + , ("query020a", "query020b") + , ("query021a", "query021b") + , ("query022a", "query022b") + , ("query023a", "query023b") + , ("query024a", "query024b") + , ("query025a", "query025b") + , ("query026a", "query026b") + , ("query027a", "query027b") + , ("query028a", "query028b") + , ("query029a", "query029b") + , ("query030a", "query030b") + , ("query031a", "query031b") + , ("query032a", "query032b") + , ("query033a", "query033b") + , ("query034a", "query034b") + , ("query035a", "query035b") + , ("query036a", "query036b") + , ("query037a", "query037b") + , ("query038a", "query038b") + , ("query039a", "query039b") + , ("query040a", "query040b") + , ("query041a", "query041b") + , ("query042a", "query042b") + , ("query043a", "query043b") + , ("query044a", "query044b") + , ("query045a", "query045b") + , ("query046a", "query046b") + , ("query047a", "query047b") + , ("query048a", "query048b") + , ("query049a", "query049b") + , ("query050a", "query050b") + ] ===================================== testsuite/tests/perf/compiler/all.T ===================================== @@ -686,6 +686,12 @@ test ('T13820', ], compile, ['-v0']) +test ('T13960', + [ collect_compiler_stats('peak_megabytes_allocated', 20), + collect_compiler_stats('bytes allocated', 2), + ], + compile, + ['-O']) test ('T14766', [ collect_compiler_stats('bytes allocated',2), pre_cmd('python3 genT14766.py > T14766.hs'), View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/7c6cbeee4b9826409267e722f3ff32… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/7c6cbeee4b9826409267e722f3ff32… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][wip/romes/25636] 17 commits: ghc-boot: remove unused SizedSeq instances and functions
by Rodrigo Mesquita (＠alt-romes) 01 Apr '26

01 Apr '26

Rodrigo Mesquita pushed to branch wip/romes/25636 at Glasgow Haskell Compiler / GHC Commits: cf942119 by Cheng Shao at 2026-03-30T15:24:37-04:00 ghc-boot: remove unused SizedSeq instances and functions This commit removes unused `SizedSeq` instances and functions, only keeping the bits we need for hpc tick sequence for now. - - - - - 22c5b7cc by Cheng Shao at 2026-03-30T15:24:38-04:00 ghci: remove unused GHCi.BinaryArray This patch removes the unused `GHCi.BinaryArray` module from `ghci`. Closes #27108. - - - - - 77abb4ab by Cheng Shao at 2026-03-30T15:25:21-04:00 testsuite: mark T17912 as fragile on Windows T17912 is still fragile on Windows, it sometimes unexpectedly pass in CI. This especially strains our already scarce Windows CI runner resources. Mark it as fragile on Windows for the time being. - - - - - d741a6cc by Andreas Klebinger at 2026-03-31T04:39:33-04:00 Bump minimum shake version for hadrian. We also add the shake version we want to stack.yaml Fixes #26884 - - - - - 5e556f9e by Vladislav Zavialov at 2026-03-31T04:40:16-04:00 Status check for the HsType~HsExpr refactoring (#25121) Add a test case to track the status of a refactoring project within GHC whose goal is to arrive at the following declaration: type HsType = HsExpr The rationale for this is to increase code reuse between the term- and type-level code in the compiler front-end (AST, parser, renamer, type checker). The status report is saved to testsuite/tests/ghc-api/T25121_status.stdout and provides useful insights into what needs to happen to make progress on the ticket. - - - - - acffb1b1 by fendor at 2026-03-31T04:41:02-04:00 Extract Binary instances to `GHC.ByteCode.Binary` - - - - - e2ea8e25 by fendor at 2026-03-31T04:41:02-04:00 Add `seqNonEmpty` for evaluating `NonEmpty a` - - - - - 048b00b7 by fendor at 2026-03-31T04:41:02-04:00 Record `LinkableUsage` instead of `Linkable` in `LoaderState` Retaining a ByteCode `Linkable` after it has been loaded retains its `UnlinkedBCO`, keeping it alive for the remainder of the program. This starts accumulating a lot of `UnlinkedBCO` and memory over time. However, the `Linkable` is merely used to later record its usage in `mkObjectUsage`, which is used for recompilation checking. However, this is incorrect, as the interface file and bytecode objects could be in different states, e.g. the interface changes, but the bytecode library hasn't changed so we don't need to recompile and vice versa. By computing a `Fingerprint` for the `ModuleByteCode`, and recording it in the `LinkableUsage`, we know precisely whether the `ByteCode` object on disk is outdated. Thus, parts of this commit just makes sure that we efficiently compute a `Fingerprint` for `ModuleByteCode` and store it in the on-disk representation of `ModuleByteCode`. We change the `LoaderState` to retain `LinkableUsage`, which is smaller representation of a `Linkable`. This allows us to free the unneeded fields of `Linkable` after linking them. We declare the following memory invariants that this commit implements: * No `LinkablePart` should be retained from `LoaderState`. * `Linkable`s should be unloaded after they have been loaded. These invariants are unfortunately tricky to automatically uphold, so we are simply documenting our assumptions for now. We introduce the `linkable-space` test which makes sure that after loading, no `DotGBC` or `UnlinkedBCO` is retained. ------------------------- Metric Increase: MultiLayerModulesTH_OneShot ------------------------- We allocate a bit more, but the peak number of bytes doesn't change. While a bit unfortunate, accepting the metric increase. We add multiple new performance measurements where we were able to observe the desired memory invariants. Further, we add regression tests to validate that the recompilation checker behaves more correct than before. - - - - - 2d1c1997 by Simon Jakobi at 2026-03-31T04:41:46-04:00 Eliminate dictionary-passing in ListMap operations Mark the ListMap helpers 'INLINABLE' so importing modules can specialise the 'TrieMap (ListMap m)' methods and avoid recursive dictionary-passing. See Note [Making ListMap operations specialisable]. Fixes #27097 - - - - - ed2c6570 by Cheng Shao at 2026-03-31T04:42:33-04:00 testsuite: fix testdir cleanup logic on Windows testdir cleanup is unreliable on Windows (#13162) and despite existing hacks in the driver, new failure mode has occurred. This patch makes it print the warning and carry on when failed to clean up a testdir, instead of reporting a spurious framework failure. See added comment for detailed explanation. - - - - - 44e3771c by Rodrigo Mesquita at 2026-03-31T18:08:53+01:00 Add test for #25636 The existing test behaviour of "T23146_liftedeq" changed because the simplifier now does a bit more inlining. We can restore the previous bad behavior by using an OPAQUE pragma. This test doubles as a test for #25636 when run in ghci, so we add it as such. - - - - - bf21a448 by Rodrigo Mesquita at 2026-03-31T18:08:53+01:00 refactor: protoBCOName is always a Name Simplifies the code by removing the unnecessary type argument to ProtoBCO which was always 'Name' - - - - - 63489d13 by Rodrigo Mesquita at 2026-03-31T18:11:33+01:00 Allocate static constructors for bytecode This commit adds support for static constructors when compiling and linking ByteCode objects. Top-level StgRhsCon get lowered to ProtoStaticCons rather than to ProtoBCOs. A ProtoStaticCon gets allocated directly as a data con application on the heap (using the new primop newConApp#). Previously, we would allocate a ProtoBCO which, when evaluated, would PACK and return the constructor. A few more details are given in Note [Static constructors in Bytecode]. Secondly, this commit also fixes issue #25636 which was caused by linking *unlifted* constructors in BCO instructions as - (1) a thunk indexing the array of BCOs in a module - (2) which evaluated to a BCO which still had to be evaluated to return the unlifted constructor proper. The (2) issue has been resolved by allocating the static constructors directly. The (1) issue can be resolved by ensuring that we allocate all unlifted top-level constructors eagerly, and leave the knot-tying for the lifted BCOs and top-level constructors only. The top-level unlifted constructors are never mutually recursive, so we can allocate them all in one go as long as we do it in topological order. Lifted fields of unlifted constructors can still be filled by the knot-tied lifted variables since in those fields it is fine to keep those thunks. See Note [Tying the knot in createBCOs] for more details. Fixes #25636 - - - - - 0d65aeb4 by Rodrigo Mesquita at 2026-03-31T18:11:34+01:00 Revert "StgToByteCode: Assert that PUSH_G'd values are lifted" This reverts commit ec26c54d818e0cd328276196930313f66b780905. Ever since f7a22c0f4e9ae0dc767115d4c53fddbd8372b777, we now do support and will link top-level unlifted constructors into evaluated and properly tagged values which we can reference with PUSH_G. This assertion is no longer true and triggered a failure in T25636 - - - - - dba7f6c8 by Rodrigo Mesquita at 2026-03-31T18:11:34+01:00 refactor: Tag more remote Ptrs as RemotePtr Pure refactor which improves the API of - GHC.ByteCode.Linker - GHC.Runtime.Interpreter - GHC.Runtime.Interpreter.Types.SymbolCache by using `RemotePtr` for more functions which used to return `Ptr`s that could potentially be in a foreign process. E.g. `lookupIE`, `lookupStaticPtr`, etc... - - - - - eb6b0051 by Rodrigo Mesquita at 2026-03-31T18:11:34+01:00 Add float# and subword tests for #25636 These tests cover that static constructors in bytecode work correctly for Float# and subword values (Word8#, Word16#) - - - - - 42866500 by Rodrigo Mesquita at 2026-03-31T18:16:54+01:00 test: Validate topoSort logic in createBCOs This test validates that the topological sorting and ordering of the unlifted constructors and lifted constructors in `createBCOs` is correct. See `Note [Tying the knot in createBCOs]` for why tying the knot for the created BCOs is slightly difficult and why the topological sorting is necessary. This test fails when `let topoSortedObjs = topSortObjs objs` is substituted by `let topoSortedObjs = zip [0..] objs`, thus witnessing the toposort logic is correct and necessary. The test calls the ghci `createBCOs` directly because it is currently impossible to construct in Source Haskell a situation where a top-level static unlifted constructor depends on another (we don't have top-level unlifted constructors except for nullary constructors like `Leaf :: (UTree :: UnliftedType)`). This is another test for fix for #25636 - - - - - 108 changed files: - compiler/GHC/Builtin/primops.txt.pp - compiler/GHC/ByteCode/Asm.hs - + compiler/GHC/ByteCode/Binary.hs - compiler/GHC/ByteCode/Instr.hs - compiler/GHC/ByteCode/Linker.hs - + compiler/GHC/ByteCode/Recomp/Binary.hs - compiler/GHC/ByteCode/Serialize.hs - compiler/GHC/ByteCode/Types.hs - compiler/GHC/Cmm/Liveness.hs - compiler/GHC/Data/TrieMap.hs - compiler/GHC/Driver/Hooks.hs - compiler/GHC/Driver/Main.hs - compiler/GHC/Driver/Pipeline.hs - compiler/GHC/Driver/Plugins.hs - compiler/GHC/HsToCore/Usage.hs - compiler/GHC/Iface/Recomp.hs - compiler/GHC/Iface/Recomp/Types.hs - compiler/GHC/Linker/ByteCode.hs - compiler/GHC/Linker/Deps.hs - compiler/GHC/Linker/Loader.hs - compiler/GHC/Linker/Types.hs - compiler/GHC/Runtime/Interpreter.hs - compiler/GHC/Runtime/Interpreter/Types/SymbolCache.hs - compiler/GHC/Runtime/Loader.hs - compiler/GHC/StgToByteCode.hs - compiler/GHC/StgToCmm/DataCon.hs - compiler/GHC/StgToCmm/Layout.hs - compiler/GHC/StgToCmm/Prim.hs - compiler/GHC/StgToJS/Prim.hs - compiler/GHC/Tc/Types.hs - compiler/GHC/Tc/Utils/Monad.hs - compiler/GHC/Unit/Home/ModInfo.hs - compiler/GHC/Unit/Module/Deps.hs - compiler/GHC/Unit/Module/Status.hs - compiler/GHC/Utils/Misc.hs - compiler/ghc.cabal.in - ghc/GHCi/Leak.hs - hadrian/hadrian.cabal - hadrian/stack.yaml - libraries/base/tests/IO/all.T - libraries/ghc-boot/GHC/Data/SizedSeq.hs - − libraries/ghci/GHCi/BinaryArray.hs - libraries/ghci/GHCi/CreateBCO.hs - libraries/ghci/GHCi/ResolvedBCO.hs - libraries/ghci/ghci.cabal.in - rts/Interpreter.c - rts/PrimOps.cmm - rts/RtsSymbols.c - rts/include/Rts.h - rts/include/rts/storage/ClosureMacros.h - rts/include/stg/MiscClosures.h - testsuite/driver/testlib.py - + testsuite/tests/bytecode/TLinkable/BCOTemplate.hs - + testsuite/tests/bytecode/TLinkable/LinkableUsage01.stderr - + testsuite/tests/bytecode/TLinkable/LinkableUsage02.stderr - + testsuite/tests/bytecode/TLinkable/Makefile - + testsuite/tests/bytecode/TLinkable/all.T - + testsuite/tests/bytecode/TLinkable/genLinkables.sh - + testsuite/tests/bytecode/TLinkable/linkable-space.hs - + testsuite/tests/bytecode/TLinkable/linkable-space.stdout - testsuite/tests/codeGen/should_run/T23146/T23146_liftedeq.hs - + testsuite/tests/codeGen/should_run/T23146/T25636.script - + testsuite/tests/codeGen/should_run/T23146/T25636.stdout - testsuite/tests/codeGen/should_run/T23146/all.T - + testsuite/tests/codeGen/should_run/T25636a/T25636a.script - + testsuite/tests/codeGen/should_run/T25636a/T25636a.stdout - + testsuite/tests/codeGen/should_run/T25636a/all.T - + testsuite/tests/codeGen/should_run/T25636b/T25636b.script - + testsuite/tests/codeGen/should_run/T25636b/T25636b.stdout - + testsuite/tests/codeGen/should_run/T25636b/all.T - + testsuite/tests/codeGen/should_run/T25636c/T25636c.script - + testsuite/tests/codeGen/should_run/T25636c/T25636c.stdout - + testsuite/tests/codeGen/should_run/T25636c/all.T - + testsuite/tests/codeGen/should_run/T25636d/T25636d.script - + testsuite/tests/codeGen/should_run/T25636d/T25636d.stdout - + testsuite/tests/codeGen/should_run/T25636d/all.T - + testsuite/tests/codeGen/should_run/T25636e/T25636e.script - + testsuite/tests/codeGen/should_run/T25636e/T25636e.stdout - + testsuite/tests/codeGen/should_run/T25636e/all.T - testsuite/tests/count-deps/CountDepsAst.stdout - testsuite/tests/count-deps/CountDepsParser.stdout - testsuite/tests/driver/multipleHomeUnits/multipleHomeUnits_recomp_th.stdout - + testsuite/tests/driver/recomp022/A1.hs - + testsuite/tests/driver/recomp022/A2.hs - + testsuite/tests/driver/recomp022/A3.hs - + testsuite/tests/driver/recomp022/B.hs - + testsuite/tests/driver/recomp022/C.hs - + testsuite/tests/driver/recomp022/Makefile - + testsuite/tests/driver/recomp022/all.T - + testsuite/tests/driver/recomp022/recomp022a.stdout - + testsuite/tests/driver/recomp022/recomp022b.stdout - + testsuite/tests/ghc-api/T25121_status.hs - + testsuite/tests/ghc-api/T25121_status.stdout - testsuite/tests/ghc-api/all.T - testsuite/tests/ghci.debugger/scripts/print034.stdout - testsuite/tests/ghci/should_run/BinaryArray.hs - + testsuite/tests/ghci/should_run/T25636f.hs - + testsuite/tests/ghci/should_run/T25636f.stdout - testsuite/tests/ghci/should_run/all.T - testsuite/tests/interface-stability/base-exports.stdout - testsuite/tests/interface-stability/base-exports.stdout-javascript-unknown-ghcjs - testsuite/tests/interface-stability/base-exports.stdout-mingw32 - testsuite/tests/interface-stability/base-exports.stdout-ws-32 - testsuite/tests/interface-stability/ghc-experimental-exports.stdout - testsuite/tests/interface-stability/ghc-experimental-exports.stdout-mingw32 - testsuite/tests/interface-stability/ghc-prim-exports.stdout - testsuite/tests/interface-stability/ghc-prim-exports.stdout-mingw32 - utils/deriveConstants/Main.hs The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/eb40cc66d42a48cc2bb6efcf63c3f7… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/eb40cc66d42a48cc2bb6efcf63c3f7… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][master] ci: allow metric decrease for two tests on i386
by Marge Bot (＠marge-bot) 01 Apr '26

01 Apr '26

Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC Commits: 6a10045c by mangoiv at 2026-03-31T13:15:43-04:00 ci: allow metric decrease for two tests on i386 There has been a nightly failure on i386 due to a compiler runtime improvement on i386 debian 12. We allow that. Metric Decrease (test_env='i386-linux-deb12'): T12707 T8095 - - - - - 0 changed files: Changes: View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/6a10045ca09c2c84a175bc2b651cfee… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/6a10045ca09c2c84a175bc2b651cfee… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][master] Add regression test for #18177
by Marge Bot (＠marge-bot) 01 Apr '26

01 Apr '26

Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC Commits: d9388e29 by Simon Jakobi at 2026-03-31T13:14:59-04:00 Add regression test for #18177 Closes #18177. Assisted-by: Codex - - - - - 2 changed files: - + testsuite/tests/driver/T18177.hs - testsuite/tests/driver/all.T Changes: ===================================== testsuite/tests/driver/T18177.hs ===================================== @@ -0,0 +1 @@ +module T18177 where ===================================== testsuite/tests/driver/all.T ===================================== @@ -314,6 +314,12 @@ test('MultiRootsErr', normal, multimod_compile_fail, ['MultiRootsErr', 'MultiRoo test('patch-level2', normal, compile, ['-Wcpp-undef']) test('T16476a', normal, makefile_test, []) test('T16476b', normal, makefile_test, []) + +# Test that GHC can handle an empty preprocessor response file. +# This used to cause GHC to hang indefinitely: #18177 +test('T18177', [js_skip, pre_cmd('touch cpp-args')], compile, + ['-v0 -fforce-recomp -fhpc -optP@cpp-args -optP-DX']) + test('T20569', extra_files(["T20569/"]), makefile_test, []) test('T21866', normal, multimod_compile, ['T21866','-no-link']) test('T21349', extra_files(['T21349']), makefile_test, []) View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/d9388e297e3e61c1ce5cb1f54a577fc… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/d9388e297e3e61c1ce5cb1f54a577fc… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc][wip/spj-apporv-Oct24] 11 commits: ghc-boot: remove unused SizedSeq instances and functions
by Apoorv Ingle (＠ani) 01 Apr '26

01 Apr '26

Apoorv Ingle pushed to branch wip/spj-apporv-Oct24 at Glasgow Haskell Compiler / GHC Commits: cf942119 by Cheng Shao at 2026-03-30T15:24:37-04:00 ghc-boot: remove unused SizedSeq instances and functions This commit removes unused `SizedSeq` instances and functions, only keeping the bits we need for hpc tick sequence for now. - - - - - 22c5b7cc by Cheng Shao at 2026-03-30T15:24:38-04:00 ghci: remove unused GHCi.BinaryArray This patch removes the unused `GHCi.BinaryArray` module from `ghci`. Closes #27108. - - - - - 77abb4ab by Cheng Shao at 2026-03-30T15:25:21-04:00 testsuite: mark T17912 as fragile on Windows T17912 is still fragile on Windows, it sometimes unexpectedly pass in CI. This especially strains our already scarce Windows CI runner resources. Mark it as fragile on Windows for the time being. - - - - - d741a6cc by Andreas Klebinger at 2026-03-31T04:39:33-04:00 Bump minimum shake version for hadrian. We also add the shake version we want to stack.yaml Fixes #26884 - - - - - 5e556f9e by Vladislav Zavialov at 2026-03-31T04:40:16-04:00 Status check for the HsType~HsExpr refactoring (#25121) Add a test case to track the status of a refactoring project within GHC whose goal is to arrive at the following declaration: type HsType = HsExpr The rationale for this is to increase code reuse between the term- and type-level code in the compiler front-end (AST, parser, renamer, type checker). The status report is saved to testsuite/tests/ghc-api/T25121_status.stdout and provides useful insights into what needs to happen to make progress on the ticket. - - - - - acffb1b1 by fendor at 2026-03-31T04:41:02-04:00 Extract Binary instances to `GHC.ByteCode.Binary` - - - - - e2ea8e25 by fendor at 2026-03-31T04:41:02-04:00 Add `seqNonEmpty` for evaluating `NonEmpty a` - - - - - 048b00b7 by fendor at 2026-03-31T04:41:02-04:00 Record `LinkableUsage` instead of `Linkable` in `LoaderState` Retaining a ByteCode `Linkable` after it has been loaded retains its `UnlinkedBCO`, keeping it alive for the remainder of the program. This starts accumulating a lot of `UnlinkedBCO` and memory over time. However, the `Linkable` is merely used to later record its usage in `mkObjectUsage`, which is used for recompilation checking. However, this is incorrect, as the interface file and bytecode objects could be in different states, e.g. the interface changes, but the bytecode library hasn't changed so we don't need to recompile and vice versa. By computing a `Fingerprint` for the `ModuleByteCode`, and recording it in the `LinkableUsage`, we know precisely whether the `ByteCode` object on disk is outdated. Thus, parts of this commit just makes sure that we efficiently compute a `Fingerprint` for `ModuleByteCode` and store it in the on-disk representation of `ModuleByteCode`. We change the `LoaderState` to retain `LinkableUsage`, which is smaller representation of a `Linkable`. This allows us to free the unneeded fields of `Linkable` after linking them. We declare the following memory invariants that this commit implements: * No `LinkablePart` should be retained from `LoaderState`. * `Linkable`s should be unloaded after they have been loaded. These invariants are unfortunately tricky to automatically uphold, so we are simply documenting our assumptions for now. We introduce the `linkable-space` test which makes sure that after loading, no `DotGBC` or `UnlinkedBCO` is retained. ------------------------- Metric Increase: MultiLayerModulesTH_OneShot ------------------------- We allocate a bit more, but the peak number of bytes doesn't change. While a bit unfortunate, accepting the metric increase. We add multiple new performance measurements where we were able to observe the desired memory invariants. Further, we add regression tests to validate that the recompilation checker behaves more correct than before. - - - - - 2d1c1997 by Simon Jakobi at 2026-03-31T04:41:46-04:00 Eliminate dictionary-passing in ListMap operations Mark the ListMap helpers 'INLINABLE' so importing modules can specialise the 'TrieMap (ListMap m)' methods and avoid recursive dictionary-passing. See Note [Making ListMap operations specialisable]. Fixes #27097 - - - - - ed2c6570 by Cheng Shao at 2026-03-31T04:42:33-04:00 testsuite: fix testdir cleanup logic on Windows testdir cleanup is unreliable on Windows (#13162) and despite existing hacks in the driver, new failure mode has occurred. This patch makes it print the warning and carry on when failed to clean up a testdir, instead of reporting a spurious framework failure. See added comment for detailed explanation. - - - - - 411a5d42 by Apoorv Ingle at 2026-03-31T11:39:04-05:00 Work for #25001 Notes added [Error Context Stack] [Typechecking by expansion: overview] [splitHsApps, XExpr and tcExprSigma] Notes updated Note [Expanding HsDo with XXExprGhcRn] ------------------------- Metric Decrease: T9020 ------------------------- * Simplifies the implementations of `tcExpr` to work on `XExpr` * Removes `VACtxt` (and its associated `VAExpansion` and `VACall`) datatype, it is subsumed by simply a `SrcSpan`. * Removes the function `addHeadCtxt` as it is now mearly setting a location * simplify `addArgCtxt`. * The function `tcValArgs` does its own argument number management * Makes `splitHsApps` not look through `XExpr` * `tcExprSigma` is called if the head of the expression after calling `splitHsApps` turns out to be an `XExpr` * Removes location information from `OrigPat` payload * Removes special case of tcBody from `tcLambdaMatches` * Removes special case of `dsExpr` for `ExpandedThingTc` * Rename `HsThingRn` to `SrcCodeCtxt` * Renames `tcMonoExpr` -> `tcMonoLExpr`, `tcMonoExprNC` -> `tcMonoLExpr` * Renames `EValArg`, `EValArgQL` fields: `ea_ctxt` -> `ea_loc_span` and `eaql_ctx` -> `eaql_loc_span` * Remove `PopErrCtxt` from `XXExprGhcRn` * fun_orig in tcApp depends on the SrcSpan of the head of the application chain (similar to addArgCtxt) * rename fun_ctxt to fun_lspan, fun_orig passed in tcInstFun to default to app chain head if its user located, fall back to srcCodeOrigin if it's a generated location * Make sure only expression wrapped around generated src span are ignored while adding them to the error context stack * `getDeepSubsumptionFlag_DataConHead` performs a non-trivial traversal if the expression passed to it is complex. This traversal is necessary if the head of the function is an `XExpr` and `splitHsApps` does not look through them - The deepsubsumption flag is stored in EVAlArgQL to reduce the need to call `getDeepSubsumptionFlag_DataConHead` - `getDeepSubsumptionFlag_DataConHead` is called in `tcExprSigma` and `tcInferAppHead` to reduce AST traversals * Make a new variant `GeneratedSrcSpan` in `SrcSpan` for HIEAst Nodes - wrap `fromListN` with a generated src span with GeneratedSrcSpanDetails field to store the original srcspan - remove `UnhelpfulGenerated` from `UnhelpfulSpanReason` and into new datatype `GeneratedSrcSpanDetails` * Merge SrcCodeOrigin with HsCtxt * Landmark are now just computed on the fly * HsExpand mediates between expansion and typechecking * Make HsExpandedRn and HsExpandedTc payload LExpr, * Add tcHsExpand type checking expanded Expressions * Add Note to explain the tcExprSigma, QuickLook and Deepsubsumption flag impl [splitHsApps, XExpr and tcExprSigma] - - - - - 162 changed files: - compiler/GHC.hs - + compiler/GHC/ByteCode/Binary.hs - + compiler/GHC/ByteCode/Recomp/Binary.hs - compiler/GHC/ByteCode/Serialize.hs - compiler/GHC/Data/TrieMap.hs - compiler/GHC/Driver/Hooks.hs - compiler/GHC/Driver/Main.hs - compiler/GHC/Driver/Pipeline.hs - compiler/GHC/Driver/Plugins.hs - compiler/GHC/Hs/DocString.hs - compiler/GHC/Hs/Expr.hs - compiler/GHC/Hs/Expr.hs-boot - compiler/GHC/Hs/Instances.hs - compiler/GHC/Hs/Syn/Type.hs - compiler/GHC/HsToCore/Expr.hs - compiler/GHC/HsToCore/Match.hs - compiler/GHC/HsToCore/Monad.hs - compiler/GHC/HsToCore/Pmc.hs - compiler/GHC/HsToCore/Quote.hs - compiler/GHC/HsToCore/Ticks.hs - compiler/GHC/HsToCore/Usage.hs - compiler/GHC/Iface/Ext/Ast.hs - compiler/GHC/Iface/Ext/Utils.hs - compiler/GHC/Iface/Recomp.hs - compiler/GHC/Iface/Recomp/Types.hs - compiler/GHC/Linker/ByteCode.hs - compiler/GHC/Linker/Deps.hs - compiler/GHC/Linker/Loader.hs - compiler/GHC/Linker/Types.hs - compiler/GHC/Parser/HaddockLex.x - compiler/GHC/Rename/Expr.hs - compiler/GHC/Rename/Names.hs - compiler/GHC/Rename/Utils.hs - compiler/GHC/Runtime/Debugger/Breakpoints.hs - compiler/GHC/Runtime/Loader.hs - compiler/GHC/Tc/Deriv.hs - compiler/GHC/Tc/Deriv/Infer.hs - compiler/GHC/Tc/Deriv/Utils.hs - compiler/GHC/Tc/Errors.hs - compiler/GHC/Tc/Errors/Ppr.hs - compiler/GHC/Tc/Errors/Types.hs - compiler/GHC/Tc/Gen/App.hs - + compiler/GHC/Tc/Gen/App.hs-boot - compiler/GHC/Tc/Gen/Bind.hs - compiler/GHC/Tc/Gen/Do.hs - compiler/GHC/Tc/Gen/Export.hs - compiler/GHC/Tc/Gen/Expr.hs - compiler/GHC/Tc/Gen/Expr.hs-boot - compiler/GHC/Tc/Gen/Head.hs - compiler/GHC/Tc/Gen/HsType.hs - compiler/GHC/Tc/Gen/Match.hs - compiler/GHC/Tc/Gen/Match.hs-boot - compiler/GHC/Tc/Gen/Pat.hs - compiler/GHC/Tc/Gen/Sig.hs - compiler/GHC/Tc/Gen/Splice.hs - compiler/GHC/Tc/Instance/Class.hs - compiler/GHC/Tc/Module.hs - compiler/GHC/Tc/Solver/Solve.hs - compiler/GHC/Tc/TyCl.hs - compiler/GHC/Tc/TyCl/Class.hs - compiler/GHC/Tc/TyCl/Instance.hs - compiler/GHC/Tc/TyCl/PatSyn.hs - compiler/GHC/Tc/Types.hs - compiler/GHC/Tc/Types/BasicTypes.hs - 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testsuite/tests/rep-poly/RepPolyRecordUpdate.stderr - + testsuite/tests/typecheck/should_compile/ExpansionQLIm.hs - testsuite/tests/typecheck/should_compile/T14590.stderr - testsuite/tests/typecheck/should_compile/all.T - testsuite/tests/typecheck/should_compile/valid_hole_fits.stderr - testsuite/tests/typecheck/should_fail/DoExpansion1.stderr - testsuite/tests/typecheck/should_fail/DoExpansion2.stderr - testsuite/tests/typecheck/should_fail/T10971d.stderr - testsuite/tests/typecheck/should_fail/T13311.stderr - testsuite/tests/typecheck/should_fail/T3323.stderr - testsuite/tests/typecheck/should_fail/T3613.stderr - testsuite/tests/typecheck/should_fail/T6069.stderr - testsuite/tests/typecheck/should_fail/T7851.stderr - testsuite/tests/typecheck/should_fail/T7857.stderr - testsuite/tests/typecheck/should_fail/T8603.stderr - testsuite/tests/typecheck/should_fail/T9612.stderr - testsuite/tests/typecheck/should_fail/tcfail102.stderr - testsuite/tests/typecheck/should_fail/tcfail128.stderr - testsuite/tests/typecheck/should_fail/tcfail140.stderr - testsuite/tests/typecheck/should_fail/tcfail181.stderr - utils/check-exact/ExactPrint.hs - utils/check-exact/Parsers.hs - utils/check-exact/Transform.hs - utils/check-exact/Utils.hs - utils/haddock/haddock-api/src/Haddock/Backends/Hyperlinker/Parser.hs - utils/haddock/haddock-api/src/Haddock/Backends/Xhtml/Utils.hs The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/6beed0814ab20adffa66042d31f1ff… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/6beed0814ab20adffa66042d31f1ff… You're receiving this email because of your account on gitlab.haskell.org.

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[Git][ghc/ghc] Pushed new branch wip/ani/better-expansion
by Simon Peyton Jones (＠simonpj) 01 Apr '26

01 Apr '26

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

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