January 2016 - ghc-tickets

[GHC] #9518: Improve error message for unacceptable role annotations
by GHC 19 Feb '16

19 Feb '16

#9518: Improve error message for unacceptable role annotations -------------------------------------+------------------------------------- Reporter: dmcclean | Owner: Type: feature request | Status: new Priority: low | Milestone: Component: Compiler | Version: 7.8.3 Keywords: | Operating System: Architecture: Unknown/Multiple | Unknown/Multiple Difficulty: Unknown | Type of failure: Blocked By: | None/Unknown Related Tickets: | Test Case: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- It would be nice if this message: {{{ Role mismatch on variable a: Annotation says representational but role nominal is required while checking a role annotation for `Point' }}} Could be extended to say where the requirement arises. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9518> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #8981: ghc-pkg complains about missing haddock interface files
by GHC 19 Feb '16

19 Feb '16

#8981: ghc-pkg complains about missing haddock interface files --------------------------+------------------------------------------------ Reporter: | Owner: thoughtpolice | Status: new Type: bug | Milestone: 7.8.2 Priority: normal | Version: 7.8.1 Component: | Operating System: MacOS X Compiler | Type of failure: Incorrect result at runtime Keywords: ghc- | Test Case: pkg | Blocking: Architecture: x86_64 | (amd64) | Difficulty: | Unknown | Blocked By: | Related Tickets: | --------------------------+------------------------------------------------ As Conal reported on the mailing list[1], `ghc-pkg check` on Mavericks allegedly returns: {{{ bash-3.2$ ghc-pkg check Warning: haddock-interfaces: /Users/conal/.cabal/share/doc/x86_64-osx- ghc-7.8.1/uniplate-1.6.12/html/uniplate.haddock doesn't exist or isn't a file Warning: haddock-interfaces: /Users/conal/.cabal/share/doc/x86_64-osx- ghc-7.8.1/polyparse-1.9/html/polyparse.haddock doesn't exist or isn't a file Warning: haddock-interfaces: /Users/conal/.cabal/share/doc/x86_64-osx- ghc-7.8.1/ghc-syb-utils-0.2.1.2/html/ghc-syb-utils.haddock doesn't exist or isn't a file Warning: haddock-interfaces: /Users/conal/.cabal/share/doc/x86_64-osx- ghc-7.8.1/constraints-0.3.5/html/constraints.haddock doesn't exist or isn't a file Warning: haddock-html: /Users/conal/.cabal/share/doc/x86_64-osx- ghc-7.8.1/constraints-0.3.5/html doesn't exist or isn't a directory Warning: haddock-interfaces: /Users/conal/.cabal/share/doc/x86_64-osx- ghc-7.8.1/newtype-0.2/html/newtype.haddock doesn't exist or isn't a file Warning: haddock-html: /Users/conal/.cabal/share/doc/x86_64-osx- ghc-7.8.1/newtype-0.2/html doesn't exist or isn't a directory }}} It's not fatal, but makes the output much more annoying. I figured this would have been caught by validate or somesuch, but apparently not. Marking for 7.8.2. I'm looking into this soon. [1]http://www.haskell.org/pipermail/glasgow-haskell- users/2014-April/024846.html -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8981> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #11362: T6137 doesn't pass with reversed uniques
by GHC 18 Feb '16

18 Feb '16

#11362: T6137 doesn't pass with reversed uniques -------------------------------------+------------------------------------- Reporter: niteria | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: GHC rejects Unknown/Multiple | valid program Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- It fails with (full trace https://phabricator.haskell.org/P81) {{{ *** Core Lint errors : in result of Tidy Core *** <no location info>: warning: [in body of lambda with binder dt_a18nYf :: In f_a18o2M (Sum1 r_a18o2L (In ('F f_a18o2M) r_a18o2L)) o_a18o2K] Kind application error in coercion ‘Sym (TFCo:R:InioFro[0] <o_a18nYC>_N <i_a18nYD>_N <f_a18o2M>_N) <r_a18o2L>_N <o_a18o2K>_N’ Function kind = Code (Sum i_a18nYD o_a18nYC) o_a18nYC -> * Arg kinds = [(o_a18o2K, o_a18nYC)] <no location info>: warning: [in body of lambda with binder dt_a18nYf :: In f_a18o2M (Sum1 r_a18o2L (In ('F f_a18o2M) r_a18o2L)) o_a18o2K] Kind application error in coercion ‘Sym (TFCo:R:InioFro[0] <o_a18nYC>_N <i_a18nYD>_N <f_a18o2M>_N) <r_a18o2L>_N <o_a18o2K>_N’ Function kind = Code (Sum i_a18nYD o_a18nYC) o_a18nYC -> * Arg kinds = [(o_a18o2K, o_a18nYC)] }}} Steps to reproduce: 1. Add line `TEST_HC_OPTS += -dinitial-unique=16777000 -dunique-increment=-1` after line `TEST_HC_OPTS = -fforce-recomp -dcore-lint -dcmm-lint -dno-debug-output -no-user-$(GhcPackageDbFlag) -rtsopts $(EXTRA_HC_OPTS)` in `mk/test.mk` 2. `make TESTS=T6137` -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11362> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #11148: T9563 doesn't pass with reversed uniques
by GHC 18 Feb '16

18 Feb '16

#11148: T9563 doesn't pass with reversed uniques -------------------------------------+------------------------------------- Reporter: niteria | Owner: Type: bug | Status: new 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): | Wiki Page: -------------------------------------+------------------------------------- It fails with {{{ T9563.hs:18:1: error: • Can't make a derived instance of ‘Generic1 (G Int b Float)’: No family instance for ‘G Int b Float’ • In the stand-alone deriving instance for ‘Generic1 (G Int b Float)’ }}} Steps to reproduce: 1. Change line `TEST_HC_OPTS = -fforce-recomp -dcore-lint -dcmm-lint -dno-debug-output -no-user-$(GhcPackageDbFlag) -rtsopts $(EXTRA_HC_OPTS)` to `TEST_HC_OPTS = -dinitial-unique=16777206 -dunique-increment=-1 -fforce- recomp -dcore-lint -dcmm-lint -dno-debug-output -no- user-$(GhcPackageDbFlag) -rtsopts $(EXTRA_HC_OPTS)` in `mk/test.mk` 2. `make TESTS=T9563` -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11148> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #11313: Awkward error message "Expecting one fewer argument to ‘*’"
by GHC 18 Feb '16

18 Feb '16

#11313: Awkward error message "Expecting one fewer argument to ‘*’" -------------------------------------+------------------------------------- Reporter: rwbarton | Owner: Type: bug | Status: new Priority: low | Milestone: Component: Compiler | Version: 7.11 (Type checker) | 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 first error below has a strange first line. Admittedly the input is nonsense, but as `*` has no arguments, according to the March Hare, it can't have one fewer argument. Note that the second error does not contain this problematic line. {{{ rwbarton@morphism:/tmp$ ~/ghc-newest/inplace/bin/ghc-stage2 --interactive GHCi, version 7.11.20151228: http://www.haskell.org/ghc/ :? for help Prelude> import Data.Kind Prelude Data.Kind> :set -XTypeApplications Prelude Data.Kind> :t fmap @ (*) <interactive>:1:8: error: • Expecting one fewer argument to ‘*’ Expected kind ‘* -> *’, but ‘*’ has kind ‘*’ • In the type ‘*’ In the expression: fmap @* Prelude Data.Kind> :t fmap @ Int <interactive>:1:8: error: • Expected kind ‘* -> *’, but ‘Int’ has kind ‘*’ • In the type ‘Int’ In the expression: fmap @Int }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11313> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #11246: Regression typechecking type synonym which includes `Any`.
by GHC 18 Feb '16

18 Feb '16

#11246: Regression typechecking type synonym which includes `Any`. -------------------------------------+------------------------------------- Reporter: mpickering | Owner: Type: bug | 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: -------------------------------------+------------------------------------- {{{ module Foo where import GHC.Exts type Key a = Any }}} produces the error message on HEAD but compiles on 7.8.3 and 7.10.1 (thanks to Reid for testing). {{{unsafeany.hs:5:1: error: • The type family ‘Any’ should have no arguments, but has been given none • In the type synonym declaration for ‘Key’ Failed, modules loaded: none. }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11246> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #11241: Kind-level PartialTypeSignatures causes internal error
by GHC 18 Feb '16

18 Feb '16

#11241: Kind-level PartialTypeSignatures causes internal error -------------------------------------+------------------------------------- Reporter: adamgundry | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.11 (Type checker) | Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: GHC rejects Unknown/Multiple | valid program Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Consider the following module: {{{#!hs {-# LANGUAGE ExplicitForAll, KindSignatures, PartialTypeSignatures #-} foo :: forall (a :: _) . a -> a foo = id }}} In HEAD, this fails with an internal errror: {{{ • GHC internal error: ‘_’ is not in scope during type checking, but it passed the renamer tcl_env of environment: [] • In the kind ‘_’ In the type signature: foo :: forall (a :: _). a -> a }}} I would expect it to succeed and figure out that the wildcard is `*`. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11241> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #11413: GHC 8.1.20160111 fails to bootstrap itself.
by GHC 18 Feb '16

18 Feb '16

#11413: GHC 8.1.20160111 fails to bootstrap itself. -------------------------------------+------------------------------------- Reporter: kgardas | Owner: Type: bug | Status: new Priority: highest | Milestone: Component: Core | Version: 8.1 Libraries | Keywords: | Operating System: Solaris Architecture: x86 | Type of failure: Building GHC | failed Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Hello, bootstrapping GHC HEAD with HEAD is broken. The failure looks like: {{{ libraries/binary/src/Data/Binary/Builder/Base.hs:67:0: error: missing binary operator before token "(" libraries/binary/src/Data/Binary/Builder/Base.hs:114:0: error: missing binary operator before token "(" libraries/binary/src/Data/Binary/Builder/Base.hs:123:0: error: missing binary operator before token "(" `gcc' failed in phase `C pre-processor'. (Exit code: 1) gmake[1]: *** [utils/ghc-cabal/dist/build/tmp/ghc-cabal] Error 1 gmake: *** [all] Error 2 }}} I'm setting highest prio on this (as I feel) so lower this if you like. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11413> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #9611: Suggest the cause of "No instance" errors involving multiple versions of a package
by GHC 18 Feb '16

18 Feb '16

#9611: Suggest the cause of "No instance" errors involving multiple versions of a package -------------------------------------+------------------------------------- Reporter: rwbarton | Owner: Type: feature request | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.3 Keywords: | Operating System: Architecture: Unknown/Multiple | Unknown/Multiple Difficulty: Unknown | Type of failure: Blocked By: | None/Unknown Related Tickets: | Test Case: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- Suppose I have packages A-1.0, A-1.1, and B-1.0 built against A-1.0, and A (both versions) defines a type T which B defines to be an instance of some class C. If I load A-1.1 and B-1.0 into ghci and try to use the C T instance I will get a "No instance for C T" error, because T refers to A-1.1:T and B only defines an instance for A-1.0:T. However, if I don't realize this is what's going on, the error will be quite confusing as B appears to define an instance C T. Or, A could define the class C, rather than the type T, with the same result. This is quite common nowadays because there is a newer version of transformers (0.4.1.0) than the one which ships with GHC (0.3.0.0) and it's easy to end up installing mtl or lens against 0.3.0.0, and then some other package which pulls in 0.4.1.0. It would be nice to give a hint about what is going on, like {{{ No instance for (MonadIO X) arising from a use of ‘liftIO’ In the expression: ... ... Note: there is an instance transformers-0.3.0.0:MonadIO X }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9611> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #11488: -dynamic-too is entirely undocumented
by GHC 18 Feb '16

18 Feb '16

#11488: -dynamic-too is entirely undocumented -------------------------------------+------------------------------------- Reporter: bgamari | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Documentation | 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 like there are precisely zero mentions of the `-dynamic-too` flag in our user documentation. This may not be a flag that users will use often but it still needs documentation -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11488> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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