October 2018 - ghc-tickets

[GHC] #11610: Remove IEThingAll constructor from IE datatype
by GHC 11 Jan '19

11 Jan '19

#11610: Remove IEThingAll constructor from IE datatype -------------------------------------+------------------------------------- Reporter: mpickering | Owner: Type: task | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.3 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- It seems that now `IEThingWith` can include a wildcard that the `IEThingAll` constructor is a special case. I'm not sure how involved this would be but it seems worth doing. {{{ | IEThingAll (Located name) -- ^ Class/Type plus all methods/constructors -- -- - 'ApiAnnotation.AnnKeywordId's : 'ApiAnnotation.AnnOpen', -- 'ApiAnnotation.AnnDotdot','ApiAnnotation.AnnClose', -- 'ApiAnnotation.AnnType' -- For details on above see note [Api annotations] in ApiAnnotation -- See Note [Located RdrNames] in HsExpr | IEThingWith (Located name) IEWildcard [Located name] [Located (FieldLbl name)] -- ^ Class/Type plus some methods/constructors -- and record fields; see Note [IEThingWith] -- - 'ApiAnnotation.AnnKeywordId's : 'ApiAnnotation.AnnOpen', -- 'ApiAnnotation.AnnClose', -- 'ApiAnnotation.AnnComma', -- 'ApiAnnotation.AnnType' -- For details on above see note [Api annotations] in ApiAnnotation }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11610> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #15835: Internal error when splicing value constructed using typed template haskell
by GHC 11 Jan '19

11 Jan '19

#15835: Internal error when splicing value constructed using typed template haskell -------------------------------------+------------------------------------- Reporter: mpickering | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.6.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Related to #15833 Compiling Test.hs leads to an internal compiler error. https://gist.github.com/f04a613bb5e20c241c5b91c2f38b8f06 {{{ {-# LANGUAGE TemplateHaskell #-} {-# OPTIONS_GHC -ddump-splices #-} module Test where import qualified Compiler as C main :: IO () main = do $$(C.runQuery) }}} {{{ {-# LANGUAGE TemplateHaskell #-} {-# LANGUAGE ScopedTypeVariables #-} {-# LANGUAGE TypeApplications #-} {-# OPTIONS_GHC -Wall #-} module Compiler where import Language.Haskell.TH type QTExp a = Q (TExp a) fix :: (a -> a) -> a fix f = let x = f x in x while :: forall m . Monoid m => QTExp (IO m -> IO m) -> QTExp (IO m) while b = [|| fix (\r -> whenM @(IO m) ($$b r)) ||] whenM :: Monoid m => m -> m whenM _ = mempty execOp :: forall m . Monoid m => QTExp (IO m) execOp = while [|| \r -> $$(while @m [|| id ||]) >> r ||] runQuery :: QTExp (IO ()) runQuery = execOp }}} Leads to the following internal errors even though `Compiler` type checked. {{{ Prelude> :r [1 of 2] Compiling Compiler ( Compiler.hs, interpreted ) [2 of 2] Compiling Test ( Test.hs, interpreted ) Test.hs:9:6-15: Splicing expression C.runQuery ======> C.fix (\ r_a7K7 -> (C.whenM @(IO m_a7Gp)) ((\ r_a7K8 -> ((C.fix (\ r_a7K9 -> (C.whenM @(IO m_a7Gp)) (id r_a7K9))) >> r_a7K8)) r_a7K7)) Test.hs:9:6: error: • The exact Name ‘m’ is not in scope Probable cause: you used a unique Template Haskell name (NameU), perhaps via newName, but did not bind it If that's it, then -ddump-splices might be useful • In the result of the splice: $C.runQuery To see what the splice expanded to, use -ddump-splices In the Template Haskell splice $$(C.runQuery) In a stmt of a 'do' block: $$(C.runQuery) | 9 | $$(C.runQuery) | ^^^^^^^^^^ Test.hs:9:6: error: • The exact Name ‘m’ is not in scope Probable cause: you used a unique Template Haskell name (NameU), perhaps via newName, but did not bind it If that's it, then -ddump-splices might be useful • In the result of the splice: $C.runQuery To see what the splice expanded to, use -ddump-splices In the Template Haskell splice $$(C.runQuery) In a stmt of a 'do' block: $$(C.runQuery) | 9 | $$(C.runQuery) | ^^^^^^^^^^ Test.hs:9:6: error: • GHC internal error: ‘m’ is not in scope during type checking, but it passed the renamer tcl_env of environment: [a7K7 :-> Identifier[r_a7K7::a0, NotLetBound], r5Fg :-> Identifier[main::IO (), TopLevelLet [] True]] • In the first argument of ‘IO’, namely ‘m’ In the type ‘(IO m)’ In the expression: (C.whenM @(IO m)) ((\ r_a7K8 -> ((C.fix (\ r_a7K9 -> (C.whenM @(IO m)) (id r_a7K9))) >> r_a7K8)) r_a7K7) | 9 | $$(C.runQuery) | }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15835> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #13587: addTopDecls fails with typed Template Haskell
by GHC 11 Jan '19

11 Jan '19

#13587: addTopDecls fails with typed Template Haskell -------------------------------------+------------------------------------- Reporter: tmcdonell | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Template | Version: 8.2.1-rc1 Haskell | Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- The following untyped Template Haskell works as expected: {{{#!hs --- AddTopDecls.hs --- {-# LANGUAGE TemplateHaskell #-} {-# LANGUAGE QuasiQuotes #-} module AddTopDecls where import Language.Haskell.TH import Language.Haskell.TH.Syntax importDoubleToDouble :: String -> ExpQ importDoubleToDouble fname = do n <- newName fname d <- forImpD CCall unsafe fname n [t|Double -> Double|] addTopDecls [d] varE n --- Main.hs --- {-# LANGUAGE TemplateHaskell #-} module Main where import AddTopDecls main :: IO () main = do let sin' = $(importDoubleToDouble "sin") cos' = $(importDoubleToDouble "cos") -- print (sin' 0) print (cos' pi) }}} However it fails if I convert to the equivalent typed version: {{{#!hs --- AddTopDecls.hs --- {-# LANGUAGE TemplateHaskell #-} {-# LANGUAGE QuasiQuotes #-} module AddTopDecls where import Language.Haskell.TH import Language.Haskell.TH.Syntax importDoubleToDouble :: String -> Q (TExp (Double -> Double)) importDoubleToDouble fname = do n <- newName fname d <- forImpD CCall unsafe fname n [t|Double -> Double|] addTopDecls [d] unsafeTExpCoerce (varE n) --- Main.hs --- {-# LANGUAGE TemplateHaskell #-} module Main where import AddTopDecls main :: IO () main = do let sin' = $$(importDoubleToDouble "sin") cos' = $$(importDoubleToDouble "cos") -- print (sin' 0) print (cos' pi) }}} With the error: {{{ > ghci Main.hs -ddump-splices GHCi, version 8.2.0.20170404: http://www.haskell.org/ghc/ :? for help [1 of 2] Compiling AddTopDecls ( AddTopDecls.hs, interpreted ) [2 of 2] Compiling Main ( Main.hs, interpreted ) Main.hs:9:19-44: Splicing expression importDoubleToDouble "sin" ======> sin_a4s2 Main.hs:1:1: Splicing top-level declarations added with addTopDecls ======> foreign import ccall unsafe "sin" Main.sin :: Double -> Double Main.hs:9:19: error: • GHC internal error: ‘sin_a4s2’ is not in scope during type checking, but it passed the renamer tcl_env of environment: [a4dl :-> Identifier[sin'::t1, TopLevelLet [] False], a4dm :-> Identifier[cos'::t1, TopLevelLet [] False], r4cW :-> Identifier[main::IO (), TopLevelLet]] • In the expression: sin_a4s2 In the result of the splice: $importDoubleToDouble "sin" To see what the splice expanded to, use -ddump-splices In the Template Haskell splice $$(importDoubleToDouble "sin") | 9 | let sin' = $$(importDoubleToDouble "sin") | ^^^^^^^^^^^^^^^^^^^^^^^^^^ }}} Tested with 7.10.3, 8.0.2, and 8.2.0-rc1. Unfortunately I can't use untyped TH in my real use case, so if you have any suggestions for a workaround that would also be great. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13587> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #10946: Typed hole inside typed Template Haskell bracket causes panic
by GHC 11 Jan '19

11 Jan '19

#10946: Typed hole inside typed Template Haskell bracket causes panic -------------------------------------+------------------------------------- Reporter: jstolarek | Owner: Type: bug | Status: new Priority: high | Milestone: 8.0.1 Component: Template | Version: 7.10.1 Haskell | Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Compile-time Unknown/Multiple | crash Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | -------------------------------------+------------------------------------- When I say: {{{#!hs m :: a -> a m x = $$([||_||]) }}} I get: {{{ T10946.hs:47:13:ghc: panic! (the 'impossible' happened) (GHC version 7.10.1 for x86_64-unknown-linux): No skolem info: a_apJ[sk] }}} This happens both with GHC 7.10.1 and latest HEAD (e2b579e8d77357e8b36f57d15daead101586ac8e). -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10946> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #12103: Typed Template Haskell missing many utilities provided by untyped variant
by GHC 11 Jan '19

11 Jan '19

#12103: Typed Template Haskell missing many utilities provided by untyped variant -------------------------------------+------------------------------------- Reporter: bgamari | Owner: Type: bug | Status: new Priority: normal | Milestone: 8.2.1 Component: Template | Version: 8.0.1 Haskell | Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Currently typed TH feels a bit second-class as it lacks a number of handy utilities which are provided in the untyped case. In my brief look at this I encountered the following, {{{#!hs type TExpQ a = Q (TExp a) stringT :: String -> TExpQ String trueT, false :: TExpQ Bool }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12103> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #10945: Typed Template Haskell splices broken in HEAD (7.11)
by GHC 11 Jan '19

11 Jan '19

#10945: Typed Template Haskell splices broken in HEAD (7.11) -------------------------------------+------------------------------------- Reporter: jstolarek | Owner: Type: bug | Status: new Priority: high | Milestone: 8.0.1 Component: Template | Version: 7.11 Haskell | Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | -------------------------------------+------------------------------------- In the latest HEAD (e2b579e8d77357e8b36f57d15daead101586ac8e) when I say: {{{#!hs $$(return [ SigD (mkName "m") (ForallT [PlainTV (mkName "a")] [] (AppT (AppT ArrowT (VarT (mkName "a"))) (VarT (mkName "a")))) , FunD (mkName "m") [Clause [VarP (mkName "x")] (NormalB (VarE (mkName "x"))) []] ]) }}} I get: {{{ ghc-stage2: panic! (the 'impossible' happened) (GHC version 7.11.20151007 for x86_64-unknown-linux): runRnSplice $$(return [SigD (mkName "m") (ForallT [PlainTV (mkName "a")] [] (AppT (AppT ArrowT (VarT (mkName "a"))) (VarT (mkName "a")))), FunD (mkName "m") [Clause [VarP (mkName "x")] (NormalB (VarE (mkName "x"))) []]]) }}} This code compiles correctly in GHC 7.10.1. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10945> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #11452: Typed Template Haskell sneakily allows impredicativity
by GHC 11 Jan '19

11 Jan '19

#11452: Typed Template Haskell sneakily allows impredicativity -------------------------------------+------------------------------------- Reporter: goldfire | Owner: goldfire Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- The following module is accepted: {{{#!hs {-# LANGUAGE ExplicitForAll, TemplateHaskell #-} module Bug where impred :: forall a. a -> a impred = $$( [|| \x -> x ||] ) }}} But that requires an intermediate `TExp (forall a. a -> a)`. Will fix in ongoing work. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11452> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #10949: Document typed Template Haskell
by GHC 11 Jan '19

11 Jan '19

#10949: Document typed Template Haskell -------------------------------------+------------------------------------- Reporter: goldfire | Owner: Type: bug | Status: new Priority: high | Milestone: 8.0.1 Component: Template | Version: 7.10.2 Haskell | Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Documentation Unknown/Multiple | bug Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | -------------------------------------+------------------------------------- As far as I can tell, typed Template Haskell is completely missing from the manual. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10949> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #14838: missing "incomplete-patterns" warning for TH-generated functions
by GHC 11 Jan '19

11 Jan '19

#14838: missing "incomplete-patterns" warning for TH-generated functions -------------------------------------+------------------------------------- Reporter: gelisam | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Template | Version: 8.2.2 Haskell | Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Incorrect Unknown/Multiple | error/warning at compile-time Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- "incomplete-patterns" warnings are generated for TH-generated case expressions, but not for TH-generated functions, so the behaviour is inconsistent. For example: {{{#!hs {-# LANGUAGE TemplateHaskell #-} module Lib where import Language.Haskell.TH qIncompleteCase :: Q [Dec] qIncompleteCase = [d| incompleteCase :: Bool -> () incompleteCase b = case b of True -> () |] qIncompleteFunction :: Q [Dec] qIncompleteFunction =[d| incompleteFunction :: Bool -> () incompleteFunction True = () |] }}} {{{#!hs {-# LANGUAGE TemplateHaskell #-} module Bug where import Lib $qIncompleteCase $qIncompleteFunction incompleteCase' :: Bool -> () incompleteCase' b = case b of True -> () incompleteFunction' :: Bool -> () incompleteFunction' True = () }}} When compiling the above two files with `-Wall`, GHC 8.2.2 produces an "incomplete-patterns" warning for `qIncompleteCase`, `incompleteCase'`, and `incompleteFunction'`, but not for `qIncompleteFunction`. I would prefer to get a warning for `qIncompleteFunction` as well. My use case is the [https://hackage.haskell.org/package/surjective surjective] package, in which I intentionally generate code which produces warnings in order to warn the user about corresponding issues in their code. I could generate [https://github.com/gelisam/surjective/blob/master/src/Surjective.hs#L158-L1… better error messages] if GHC generated warnings for TH-generated functions as well. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14838> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #15399: Build failure on PowerPC 64-bit big endian
by GHC 11 Jan '19

11 Jan '19

#15399: Build failure on PowerPC 64-bit big endian ---------------------------------+---------------------------------------- Reporter: trommler | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.5 Keywords: | Operating System: Linux Architecture: powerpc64 | Type of failure: Building GHC failed Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: ---------------------------------+---------------------------------------- Building GHC 8.6.1 alpha 2 fails with these errors on Powerpc 64-bit big endian Linux: {{{ [ 5076s] utils/check-ppr/Main.hs:44:18: error: [ 5076s] * GHC internal error: `astFile' is not in scope during type checking, but it passed the renamer [ 5076s] tcl_env of environment: [agVj :-> Identifier[libdir::FilePath, NotLetBound], [ 5076s] agVk :-> Identifier[fileName::String, NotLetBound], [ 5076s] agVl :-> Identifier[p::a, NotLetBound], [ 5076s] agVo :-> Identifier[anns::ApiAnns, TopLevelLet [agVl :-> p] False], [ 5076s] agVp :-> Identifier[pragmas::String, TopLevelLet [agVo :-> anns] False], [ 5076s] agVq :-> Identifier[newFile::FilePath, TopLevelLet [agVk :-> fileName] False], [ 5076s] rfRp :-> Identifier[usage::String, TopLevelLet [] True], [ 5076s] rfU1 :-> Identifier[main::IO (), TopLevelLet [] True], [ 5076s] rfU2 :-> Identifier[testOneFile::FilePath [ 5076s] -> String [ 5076s] -> IO (), TopLevelLet [] True], [ 5076s] rfU3 :-> Identifier[parseOneFile::FilePath [ 5076s] -> FilePath [ 5076s] -> IO [ 5076s] ParsedModule, TopLevelLet [] True], [ 5076s] rfU4 :-> Identifier[getPragmas::ApiAnns -> String, TopLevelLet], [ 5076s] rfU5 :-> Identifier[pp::forall a. [ 5076s] Outputable a => [ 5076s] a -> String, TopLevelLet [] True]] [ 5076s] * In the first argument of `writeFile', namely `astFile' [ 5076s] In a stmt of a 'do' block: writeFile astFile origAst [ 5076s] In the expression: [ 5076s] do p <- parseOneFile libdir fileName [ 5076s] let pped = pragmas ++ "\n" ++ pp (pm_parsed_source p) [ 5076s] anns = pm_annotations p [ 5076s] .... [ 5076s] writeFile astFile origAst [ 5076s] writeFile newFile pped [ 5076s] .... [ 5076s] | [ 5076s] 44 | writeFile astFile origAst [ 5076s] | ^^^^^^^ [ 5076s] utils/check-ppr/ghc.mk:18: recipe for target 'utils/check-ppr /dist-install/build/Main.o' failed [ 5076s] make[1]: *** [utils/check-ppr/dist-install/build/Main.o] Error 1 [ 5076s] make[1]: *** Waiting for unfinished jobs.... [ 5077s] [ 5077s] utils/check-api-annotations/Main.hs:116:32: error: [ 5077s] * GHC internal error: `GenericQ' is not in scope during type checking, but it passed the renamer [ 5077s] tcl_env of environment: [agZx :-> Type variable `r' = r :: k0] [ 5077s] * In the type signature: [ 5077s] everything :: (r -> r -> r) -> GenericQ r -> GenericQ r [ 5077s] | [ 5077s] 116 | everything :: (r -> r -> r) -> GenericQ r -> GenericQ r [ 5077s] | ^^^^^^^^ [ 5077s] utils/check-api-annotations/ghc.mk:18: recipe for target 'utils /check-api-annotations/dist-install/build/Main.o' failed [ 5077s] make[1]: *** [utils/check-api-annotations/dist- install/build/Main.o] Error 1 [ 5077s] [ 5077s] utils/ghctags/Main.hs:61:36: error: [ 5077s] * GHC internal error: `FoundThing' is not in scope during type checking, but it passed the renamer [ 5077s] tcl_env of environment: [rCTr :-> ATcTyCon FileData :: *, [ 5077s] rCTs :-> APromotionErr RecDataConPE, [ 5077s] rCTw :-> ATcTyCon FileName :: *] [ 5077s] * In the type `[FoundThing]' [ 5077s] In the definition of data constructor `FileData' [ 5077s] In the data declaration for `FileData' [ 5077s] | [ 5077s] 61 | data FileData = FileData FileName [FoundThing] (Map Int String) [ 5077s] | ^^^^^^^^^^ [ 5077s] utils/ghctags/ghc.mk:18: recipe for target 'utils/ghctags/dist- install/build/Main.o' failed }}} Alpha 2 builds fine on PowerPC 64-bit little endian Linux. I am setting version to 8.5 as there is no tag for 8.6.1 alpha 2 yet. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15399> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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