#11465: Eliminate check_lifted check in TcValidity -------------------------------------+------------------------------------- Reporter: simonpj | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.3 Resolution: | Keywords: 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): * cc: RyanGlScott (added) -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11465#comment:1> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

#11465: Eliminate check_lifted check in TcValidity -------------------------------------+------------------------------------- Reporter: simonpj | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1807 Wiki Page: | -------------------------------------+------------------------------------- Comment (by bgamari): Things seem to work about as one would expect with Phab:D1807. However, this error could use a bit of work, {{{ λ> :set -XTypeInType -XDataKinds -XKindSignatures -XMagicHash λ> import GHC.Exts λ> class Eq Char# where (==) = undefined <interactive>:3:10: error: Unexpected type ‘Char#’ In the class declaration for ‘Eq’ A class declaration should have form class Eq a where ... }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11465#comment:3> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

#11465: Eliminate check_lifted check in TcValidity -------------------------------------+------------------------------------- Reporter: simonpj | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1807 Wiki Page: | -------------------------------------+------------------------------------- Comment (by Simon Peyton Jones <simonpj@…>): In [changeset:"07afe448c3a83d7239054baf9d54681ca19766b0/ghc" 07afe44/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="07afe448c3a83d7239054baf9d54681ca19766b0" Remove the check_lifted check in TcValidity This patch fixes Trac #11465. The check_unlifted check really isn't necessary, as discussed in Trac #11120 comment:19. Removing it made just one test-suite change, in indexed-types/should_fail/T9357, by allowing type family F (a :: k1) :: k2 type instance F Int# = Int to be accepted. And indeed that seems entirely reasonable. }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11465#comment:5> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

#11465: Eliminate check_lifted check in TcValidity -------------------------------------+------------------------------------- Reporter: simonpj | Owner: Type: bug | Status: closed Priority: normal | Milestone: Component: Compiler | Version: 7.10.3 Resolution: fixed | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1807 Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj): Re comment:3, the error message looks fine. I think you meant `instance Eq Char#`. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11465#comment:7> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

#11465: Eliminate check_lifted check in TcValidity -------------------------------------+------------------------------------- Reporter: simonpj | Owner: Type: bug | Status: closed Priority: normal | Milestone: Component: Compiler | Version: 7.10.3 Resolution: fixed | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1807 Wiki Page: | -------------------------------------+------------------------------------- Comment (by Ben Gamari <ben@…>): In [changeset:"2df422161bccf7c0fad97e468085ebab1a17e19e/ghc" 2df42216/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="2df422161bccf7c0fad97e468085ebab1a17e19e" Add tests for #11465 and the kind invariant }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11465#comment:9> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

#11465: Eliminate check_lifted check in TcValidity -------------------------------------+------------------------------------- Reporter: simonpj | Owner: Type: bug | Status: closed Priority: normal | Milestone: 8.2.1 Component: Compiler | Version: 7.10.3 Resolution: fixed | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1807 Wiki Page: | -------------------------------------+------------------------------------- Comment (by goldfire): The test case for this was as follows {{{ class BoxIt (a :: TYPE 'Unlifted) where type Boxed a :: * boxed :: a -> Boxed a instance BoxIt Char# where type Boxed Char# = Char boxed x = C# x main :: IO () main = print $ boxed 'c'# }}} After refactoring the levity stuff as per #11471, this test failed (of course). But as I look at it, it's amazing that it ever worked. The width to the argument of `boxed` is entirely unknowable. Anyway, it's all much better now. :) -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11465#comment:11> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler