August 2017 - ghc-tickets

[GHC] #13314: StandaloneDeriving and DeriveAnyClass don't work together
by GHC 02 Aug '17

02 Aug '17

#13314: StandaloneDeriving and DeriveAnyClass don't work together -------------------------------------+------------------------------------- Reporter: chris-martin | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.2 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: -------------------------------------+------------------------------------- I'm starting with the `SPretty` example from the `DeriveAnyClass` section in the GHC users guide: {{{#!hs #!/usr/bin/env stack -- stack --resolver lts-8.0 {-# LANGUAGE DefaultSignatures, DeriveAnyClass, StandaloneDeriving #-} import Prelude import Numeric.Natural (Natural) class SPretty a where sPpr :: a -> String default sPpr :: Show a => a -> String sPpr = show }}} I can write an empty instance for `Natural`: {{{#!hs instance SPretty Natural where }}} So then I would expect to be able to write an equivalent definition using standalone deriving: {{{#!hs deriving instance SPretty Natural }}} But instead it fails with this error: {{{ error: • Can't make a derived instance of ‘SPretty Natural’: The data constructors of ‘Natural’ are not all in scope so you cannot derive an instance for it • In the stand-alone deriving instance for ‘SPretty Natural’ }}} It seems like this ought to work; I'm not sure why the constructors should need to be in scope, given that the instance can be derived trivially without defining any methods. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13314> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 6

Re: [GHC] #4530: Deriving Data for existentially quantified types
by GHC 02 Aug '17

02 Aug '17

#4530: Deriving Data for existentially quantified types -------------------------------------+------------------------------------- Reporter: mitar | Owner: (none) Type: bug | Status: closed Priority: normal | Milestone: 7.4.1 Component: Compiler | Version: 7.1 Resolution: invalid | Keywords: deriving Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by RyanGlScott): * keywords: => deriving -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/4530#comment:4> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 0

Re: [GHC] #4529: Deriving Data does not work for attached code
by GHC 02 Aug '17

02 Aug '17

#4529: Deriving Data does not work for attached code -------------------------------------+------------------------------------- Reporter: mitar | Owner: (none) Type: bug | Status: closed Priority: normal | Milestone: Component: Compiler (Type | Version: 7.1 checker) | Resolution: invalid | Keywords: deriving Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by RyanGlScott): * keywords: => deriving -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/4529#comment:4> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 0

Re: [GHC] #4309: Painfully large errors with silly GADT instances
by GHC 02 Aug '17

02 Aug '17

#4309: Painfully large errors with silly GADT instances -------------------------------------+------------------------------------- Reporter: pumpkin | Owner: (none) Type: bug | Status: closed Priority: normal | Milestone: Component: Compiler | Version: 6.12.3 Resolution: fixed | Keywords: deriving Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: | deriving/should_fail/drvfail011 Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by RyanGlScott): * keywords: => deriving -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/4309#comment:4> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 0

Re: [GHC] #4028: Derived Data instance requires Data instances for unused type parameters
by GHC 02 Aug '17

02 Aug '17

#4028: Derived Data instance requires Data instances for unused type parameters -------------------------------------+------------------------------------- Reporter: igloo | Owner: (none) Type: bug | Status: closed Priority: normal | Milestone: Not GHC Component: Compiler (Type | Version: 6.12.2 checker) | Resolution: wontfix | Keywords: deriving Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by RyanGlScott): * keywords: => deriving -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/4028#comment:8> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 0

Re: [GHC] #4019: deriving Ord can produce incorrect and inefficient instances
by GHC 02 Aug '17

02 Aug '17

#4019: deriving Ord can produce incorrect and inefficient instances -------------------------------------+------------------------------------- Reporter: rl | Owner: (none) Type: bug | Status: closed Priority: low | Milestone: Component: Compiler | Version: 6.13 Resolution: fixed | Keywords: deriving Operating System: Unknown/Multiple | Architecture: Type of failure: Incorrect result | Unknown/Multiple at runtime | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by RyanGlScott): * keywords: => deriving -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/4019#comment:16> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 0

Re: [GHC] #3368: Deriving Foldable doesn't work
by GHC 02 Aug '17

02 Aug '17

#3368: Deriving Foldable doesn't work -------------------------------------+------------------------------------- Reporter: cmcq | Owner: igloo Type: bug | Status: closed Priority: normal | Milestone: 6.12.1 Component: Compiler | Version: 6.11 Resolution: fixed | Keywords: deriving Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by RyanGlScott): * keywords: => deriving * failure: => None/Unknown -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/3368#comment:3> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 0

Re: [GHC] #4896: Deriving Data does not work for attached code
by GHC 02 Aug '17

02 Aug '17

#4896: Deriving Data does not work for attached code -------------------------------------+------------------------------------- Reporter: mitar | Owner: (none) Type: bug | Status: closed Priority: low | Milestone: 7.10.1 Component: Compiler | Version: 7.1 Resolution: fixed | Keywords: deriving Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: | deriving/should_compile/T4896 Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by RyanGlScott): * keywords: => deriving -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/4896#comment:14> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 0

Re: [GHC] #7436: Derived Foldable and Traversable instances become extremely inefficient due to eta-expansion
by GHC 02 Aug '17

02 Aug '17

#7436: Derived Foldable and Traversable instances become extremely inefficient due to eta-expansion -------------------------------------+------------------------------------- Reporter: shachaf | Owner: (none) Type: bug | Status: closed Priority: normal | Milestone: 7.6.3 Component: Compiler | Version: 7.6.1 Resolution: fixed | Keywords: deriving Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: Runtime | Test Case: performance bug | perf/should_runt/T7436 Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by RyanGlScott): * keywords: => deriving -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7436#comment:25> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 0

Re: [GHC] #7742: StandaloneDeriving on Read fails for GADTs
by GHC 02 Aug '17

02 Aug '17

#7742: StandaloneDeriving on Read fails for GADTs -------------------------------------+------------------------------------- Reporter: hoffstaetter | Owner: (none) Type: bug | Status: closed Priority: normal | Milestone: Component: Compiler | Version: 7.6.2 Resolution: invalid | Keywords: deriving Operating System: MacOS X | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by RyanGlScott): * keywords: => deriving -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7742#comment:3> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 0