April 2016 - ghc-tickets

[GHC] #11188: Confusing "parse error in pattern" for missing indentation.
by GHC 26 Mar '18

26 Mar '18

#11188: Confusing "parse error in pattern" for missing indentation. -------------------------------------+------------------------------------- Reporter: andreas.abel | Owner: Type: bug | Status: new Priority: high | Milestone: Component: Compiler | Version: 7.10.1 (Parser) | Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Other Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- The following problem exists at least in ghc 7.4.2 through 7.10.1: {{{#!hs main = do putStrLn "Hello, lots of crap" $ do a <- return 3 -- The following line is mis-indented, the error is incomprehensible c <- do return 5 }}} Error: {{{ <file>:2:3: Parse error in pattern: putStrLn Possibly caused by a missing 'do'? }}} The hint about "missing do" exists from ghc 7.8, but is wrong in this case. Problematic about this bug is that the wrong indentation can be arbitrary many lines from where ghc reports the (totally incomprehensible) error. My original problem is to find the syntax error here: {{{#!hs -- | Type check a function clause. checkClause :: Type -> A.SpineClause -> TCM Clause checkClause t c@(A.Clause (A.SpineLHS i x aps withPats) rhs0 wh) = do unless (null withPats) $ do typeError $ UnexpectedWithPatterns withPats traceCall (CheckClause t c) $ do aps <- expandPatternSynonyms aps checkLeftHandSide (CheckPatternShadowing c) (Just x) aps t $ \ (LHSResult delta ps trhs perm) -> do -- Note that we might now be in irrelevant context, -- in case checkLeftHandSide walked over an irrelevant projection pattern. -- As we will be type-checking the @rhs@ in @delta@, but the final -- body should have bindings in the order of the pattern variables, -- we need to apply the permutation to the checked rhs @v@. let mkBody v = foldr (\ x t -> Bind $ Abs x t) b xs where b = Body $ applySubst (renamingR perm) v xs = [ stringToArgName $ "h" ++ show n | n <- [0..permRange perm - 1] ] -- introduce trailing implicits for checking the where decls TelV htel t0 <- telViewUpTo' (-1) (not . visible) $ unArg trhs (body, with) <- do let n = size htel addCtxTel htel $ checkWhere (size delta + n) wh $ -- for the body, we remove the implicits again escapeContext n $ handleRHS aps (unArgs trhs) rhs0 escapeContext (size delta) $ checkWithFunction with reportSDoc "tc.lhs.top" 10 $ escapeContext (size delta) $ vcat [ text "Clause before translation:" , nest 2 $ vcat [ text "delta =" <+> prettyTCM delta , text "perm =" <+> text (show perm) , text "ps =" <+> text (show ps) , text "body =" <+> text (show body) , text "body =" <+> prettyTCM body ] ] return $ Clause { clauseRange = getRange i , clauseTel = killRange delta , clausePerm = perm , namedClausePats = ps , clauseBody = body , clauseType = Just trhs } }}} {{{ src/full/Agda/TypeChecking/Rules/Def.hs:328:5: Parse error in pattern: checkLeftHandSide Possibly caused by a missing 'do'? }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11188> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #11472: Remove CallStack CPP guards in GHC 8.2
by GHC 20 Mar '18

20 Mar '18

#11472: Remove CallStack CPP guards in GHC 8.2 -------------------------------------+------------------------------------- Reporter: bgamari | Owner: Type: task | Status: new Priority: normal | Milestone: 8.2.1 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: -------------------------------------+------------------------------------- GHC 7.10.1 didn't support `CallStack`, while its successors did. Yet in post-8.0 `master` (which needs to be buildable with the 7.10 series, including 7.10.1) references to CallStack have begun to sneak in to GHC. The first instance of this was 9d33adb6f352ad4e488067a8756928b3778920e0 but there will likely be more. I've fixed in this instance in Phab:D1812 by adding `#if` guards. These should be removed in GHC 8.2. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11472> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #10933: REMOVED pragma
by GHC 20 Mar '18

20 Mar '18

#10933: REMOVED pragma -------------------------------------+------------------------------------- Reporter: goldfire | Owner: Type: feature | Status: new request | Priority: normal | Milestone: Component: Compiler | Version: 7.10.2 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | -------------------------------------+------------------------------------- Say I have a function that's been deprecated for some time. Then I remove it. Some clients will still use the now-missing function. It would be nice to give a helpful error message, instead of a "symbol not found" error. I thus propose a `REMOVED` pragma. The syntax is identical to `DEPRECATED`, except for the name of the pragma. Whenever a `REMOVED` function is mentioned, the error message includes the string from the pragma. (This includes trying to define a `REMOVED` class method in an instance.) See Design/DeprecationMechanisms for more info and related efforts. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10933> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #11092: ApiAnnotations : make annotation for shebang
by GHC 20 Mar '18

20 Mar '18

#11092: ApiAnnotations : make annotation for shebang -------------------------------------+------------------------------------- Reporter: alanz | Owner: alanz Type: bug | Status: new Priority: normal | Milestone: 8.0.1 Component: Compiler | Version: 7.10.2 Keywords: | Operating System: Unknown/Multiple ApiAnnotations | Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Currently a valid haskell file can have a first line of the form {{{#!lhs #!/usr/bin/env runhaskell }}} This does not end up as anything that can have an API Annotation, and so gets lost on round tripping. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11092> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #10640: Document prim-ops
by GHC 20 Mar '18

20 Mar '18

#10640: Document prim-ops -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Blocked By: Test Case: | Related Tickets: Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- Currently documentation is quite scarce for many primops (particularly the BCO operations). -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10640> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #10189: explicit promotions of prefix data constructors can't be parsed naturally
by GHC 20 Mar '18

20 Mar '18

#10189: explicit promotions of prefix data constructors can't be parsed naturally -------------------------------------+------------------------------------- Reporter: Kinokkory | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.4 (Parser) | Operating System: Unknown/Multiple Keywords: | Type of failure: GHC rejects Architecture: | valid program Unknown/Multiple | Blocked By: Test Case: | Related Tickets: Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- When used as an infix operator, a data constructor is explicitly promoted simply with `'` prefixed, but when used as a prefix operator enclosed between `(` and `)`, it is explicitly promoted only with `'` put before `(`, not before the constructor. On the other hand, messages of GHC and GHCi indicate that a data constructor operator in a prefix form is promoted by putting `'` before the constructor! (as in `forall (k :: BOX) (k :: BOX). (':*)` below.) I believe that this is a matter of parsing. The parser should admit `(':*)` as well as `'(:*)` for the naturalness of the syntax. In a GHCi: {{{#!hs > :set -XDataKinds -XTypeOperators > data a :* b = a :* b > :kind! Int :* Int Int :* Int :: * = Int :* Int > :kind! Int ':* Int Int ':* Int :: * :* * = Int ':* Int > :kind! (:*) (:*) :: * -> * -> * = (:*) > :kind! '(:*) '(:*) :: k -> k1 -> k :* k1 = forall (k :: BOX) (k :: BOX). (':*) > :kind! (':*) <interactive>:1:3: parse error on input ‘:*’ }}} (By the way I assume that Template Haskell quotes (`'function` and `''Type`) are parsed by the same mechanism as the one for the explicit promotion syntax. I hope both styles of quotes for prefix operators will be admitted because currently only the `'(` `''(` style is admitted.) -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10189> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #10506: SourceNotes are not applied to all identifiers
by GHC 20 Mar '18

20 Mar '18

#10506: SourceNotes are not applied to all identifiers -------------------------------------+------------------------------------- Reporter: gridaphobe | Owner: Type: bug | Status: new Priority: normal | Milestone: 7.10.2 Component: Compiler | Version: 7.10.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Blocked By: Test Case: | Related Tickets: Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- Compiling {{{ module Foo where foo x = x + 1 bar y = foo y }}} with `-g` produces {{{ $ ghc -g -ddump-ticked test.hs [1 of 1] Compiling Foo ( test.hs, test.o ) AbsBinds [a_avC] [$dNum_avD] {Exports: [foo <= foo_amB <>] Exported types: foo :: forall a_avC. Num a_avC => a_avC -> a_avC [LclId, Str=DmdType] Binds: -- ticks = [src<test.hs:3:1-13>] foo_amB x_alA = src<test.hs:3:9-13> (+) src<test.hs:3:9> x_alA src<test.hs:3:13> 1} AbsBinds [a_avV] [$dNum_avW] {Exports: [bar <= bar_avN <>] Exported types: bar :: forall a_avV. Num a_avV => a_avV -> a_avV [LclId, Str=DmdType] Binds: -- ticks = [src<test.hs:5:1-13>] bar_avN y_amz = src<test.hs:5:9-13> foo (src<test.hs:5:13> y_amz)} }}} Note that neither the occurrence of `(+)` in `foo`, nor the occurrence of `foo` in `bar` have their own Ticks. Instead they are only covered by the Tick for the entire application `x + 1` (resp. `foo y`). I'm trying to use the new SourceNote infrastructure to map CoreExprs back to their original source location, but unfortunately I need these locations for each identifier in the source. Would it be reasonable to add a SourceNote to each occurrence of an identifier? -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10506> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #10068: Make the runtime reflection API for names, modules, locations more systematic
by GHC 20 Mar '18

20 Mar '18

#10068: Make the runtime reflection API for names, modules, locations more systematic -------------------------------------+------------------------------------- Reporter: simonpj | Owner: Type: bug | Status: new Priority: high | Milestone: 7.12.1 Component: Compiler | Version: 7.8.4 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Blocked By: Test Case: | Related Tickets: Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- Currently in `base` we have * `GHC.SrcLoc`: the data type `SrcLoc` contains `srcLocPackage` and `srcLocModule` * `Data.Typeable.Internals`: the data type `TyCon` contains `tyConPackage`, `tyConModule` and `tyConName. * `GHC.Generics`: the data type `Datatype` contains `dataTypePackage`, `dataTypeModule` and `dataTypeName` * `Data.Data`: the data type `DataType` (yes the capitalisation differs!) contains a field `tycon :: String`, and there are functions `tyconModule :: String -> String`, and `tyconUQname :: String -> String`, for parsing that string and extracting the module name and tycon name. * `GHC.StaticPtr`: the data type `StaticPtrInfo` contains `spInfoPackageKey`, `spInfoModuleName`, `spInfoName` (all `String`s). Oh, and `spInfoSrcLoc :: (Int,Int)` too! This is madness! Five different representations for the same information in one package! Let's fix this by defining some shared data types, for * `Module` = `ModuleName` + package * `Entity` = `Module` + unqualified name There would be a tiresome changeover period; but `Typeable` and `StaticPtr` are in flux anyway. Would anyone be willing to lead on this? -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10068> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #11382: Optimize Data.Char
by GHC 20 Mar '18

20 Mar '18

#11382: Optimize Data.Char -------------------------------------+------------------------------------- Reporter: bgamari | Owner: Type: bug | Status: new Priority: normal | Milestone: 8.2.1 Component: Core | Version: 7.10.3 Libraries | Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Runtime Unknown/Multiple | performance bug Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Many of the predicates in `Data.Char` do full Unicode category lookups which turns out to be quite expensive. Ideally we would handle some of the more common ASCII characters with cheaper tests before falling back to the full Unicode treatment. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11382> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #11260: Re-compilation tests fail on powerpc64
by GHC 20 Mar '18

20 Mar '18

#11260: Re-compilation tests fail on powerpc64 -------------------------------------+------------------------------------- Reporter: trommler | Owner: trommler Type: bug | Status: new Priority: normal | Milestone: 8.2.1 Component: Compiler | Version: 7.11 Keywords: | Operating System: Linux Architecture: powerpc64 | Type of failure: Compile-time | performance bug Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- recomp011: {{{ [1 of 1] Compiling Main ( Main.hs, Main.o ) [A.hsinc changed] Linking Main ... 4343 +Linking Main ... 4343 }}} recomp015: {{{ [1 of 1] Compiling Main ( Main.hs, Main.o ) Linking Main ... Running main... +Linking Main ... Running main... }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11260> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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