[GHC] #13333: Typeable regression in GHC HEAD
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: (none) Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler | Version: 8.1 (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: -------------------------------------+------------------------------------- I recently wrote some code while exploring a fix for #13327 that heavily uses poly-kinded `Typeable`. This compiles without issue on GHC 8.0.1 and 8.0.2: {{{#!hs {-# LANGUAGE ConstraintKinds #-} {-# LANGUAGE FlexibleContexts #-} {-# LANGUAGE GADTs #-} {-# LANGUAGE MultiParamTypeClasses #-} {-# LANGUAGE RankNTypes #-} {-# LANGUAGE ScopedTypeVariables #-} {-# LANGUAGE TypeInType #-} {-# LANGUAGE TypeOperators #-} module DataCast where import Data.Data import GHC.Exts (Constraint) data T (phantom :: k) = T data D (p :: k -> Constraint) (x :: j) where D :: forall (p :: k -> Constraint) (x :: k). p x => D p x class Possibly p x where possibly :: proxy1 p -> proxy2 x -> Maybe (D p x) dataCast1T :: forall k c t (phantom :: k). (Typeable k, Typeable t, Typeable phantom, Possibly Data phantom) => (forall d. Data d => c (t d)) -> Maybe (c (T phantom)) dataCast1T f = case possibly (Proxy :: Proxy Data) (Proxy :: Proxy phantom) of Nothing -> Nothing Just D -> gcast1 f }}} But on GHC HEAD, it barfs this error: {{{ Bug.hs:28:29: error: • Could not deduce (Typeable T) arising from a use of ‘gcast1’ GHC can't yet do polykinded Typeable (T :: * -> *) from the context: (Typeable k, Typeable t, Typeable phantom, Possibly Data phantom) bound by the type signature for: dataCast1T :: (Typeable k, Typeable t, Typeable phantom, Possibly Data phantom) => (forall d. Data d => c (t d)) -> Maybe (c (T phantom)) at Bug.hs:(22,1)-(25,35) or from: (k ~ *, (phantom :: k) ~~ (x :: *), Data x) bound by a pattern with constructor: D :: forall k (p :: k -> Constraint) (x :: k). p x => D p x, in a case alternative at Bug.hs:28:23 • In the expression: gcast1 f In a case alternative: Just D -> gcast1 f In the expression: case possibly (Proxy :: Proxy Data) (Proxy :: Proxy phantom) of Nothing -> Nothing Just D -> gcast1 f | 28 | Just D -> gcast1 f | ^^^^^^^^ }}} That error message itself is hilariously strange, since GHC certainly has the power to do polykinded `Typeable` nowadays. Marking as high priority since this is a regression—feel free to lower the priority if you disagree. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: (none) Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Resolution: | 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: | -------------------------------------+------------------------------------- Description changed by RyanGlScott: Old description:
I recently wrote some code while exploring a fix for #13327 that heavily uses poly-kinded `Typeable`. This compiles without issue on GHC 8.0.1 and 8.0.2:
{{{#!hs {-# LANGUAGE ConstraintKinds #-} {-# LANGUAGE FlexibleContexts #-} {-# LANGUAGE GADTs #-} {-# LANGUAGE MultiParamTypeClasses #-} {-# LANGUAGE RankNTypes #-} {-# LANGUAGE ScopedTypeVariables #-} {-# LANGUAGE TypeInType #-} {-# LANGUAGE TypeOperators #-} module DataCast where
import Data.Data import GHC.Exts (Constraint)
data T (phantom :: k) = T
data D (p :: k -> Constraint) (x :: j) where D :: forall (p :: k -> Constraint) (x :: k). p x => D p x
class Possibly p x where possibly :: proxy1 p -> proxy2 x -> Maybe (D p x)
dataCast1T :: forall k c t (phantom :: k). (Typeable k, Typeable t, Typeable phantom, Possibly Data phantom) => (forall d. Data d => c (t d)) -> Maybe (c (T phantom)) dataCast1T f = case possibly (Proxy :: Proxy Data) (Proxy :: Proxy phantom) of Nothing -> Nothing Just D -> gcast1 f }}}
But on GHC HEAD, it barfs this error:
{{{ Bug.hs:28:29: error: • Could not deduce (Typeable T) arising from a use of ‘gcast1’ GHC can't yet do polykinded Typeable (T :: * -> *) from the context: (Typeable k, Typeable t, Typeable phantom, Possibly Data phantom) bound by the type signature for: dataCast1T :: (Typeable k, Typeable t, Typeable phantom, Possibly Data phantom) => (forall d. Data d => c (t d)) -> Maybe (c (T phantom)) at Bug.hs:(22,1)-(25,35) or from: (k ~ *, (phantom :: k) ~~ (x :: *), Data x) bound by a pattern with constructor: D :: forall k (p :: k -> Constraint) (x :: k). p x => D p x, in a case alternative at Bug.hs:28:23 • In the expression: gcast1 f In a case alternative: Just D -> gcast1 f In the expression: case possibly (Proxy :: Proxy Data) (Proxy :: Proxy phantom) of Nothing -> Nothing Just D -> gcast1 f | 28 | Just D -> gcast1 f | ^^^^^^^^ }}}
That error message itself is hilariously strange, since GHC certainly has the power to do polykinded `Typeable` nowadays.
Marking as high priority since this is a regression—feel free to lower the priority if you disagree.
New description: I recently wrote some code while exploring a fix for #13327 that heavily uses poly-kinded `Typeable`. This compiles without issue on GHC 8.0.1 and 8.0.2: {{{#!hs {-# LANGUAGE ConstraintKinds #-} {-# LANGUAGE FlexibleContexts #-} {-# LANGUAGE GADTs #-} {-# LANGUAGE MultiParamTypeClasses #-} {-# LANGUAGE RankNTypes #-} {-# LANGUAGE ScopedTypeVariables #-} {-# LANGUAGE TypeInType #-} {-# LANGUAGE TypeOperators #-} module DataCast where import Data.Data import GHC.Exts (Constraint) data T (phantom :: k) = T data D (p :: k -> Constraint) (x :: j) where D :: forall (p :: k -> Constraint) (x :: k). p x => D p x class Possibly p x where possibly :: proxy1 p -> proxy2 x -> Maybe (D p x) dataCast1T :: forall k c t (phantom :: k). (Typeable k, Typeable t, Typeable phantom, Possibly Data phantom) => (forall d. Data d => c (t d)) -> Maybe (c (T phantom)) dataCast1T f = case possibly (Proxy :: Proxy Data) (Proxy :: Proxy phantom) of Nothing -> Nothing Just D -> gcast1 f }}} But on GHC HEAD, it barfs this error: {{{ $ ~/Software/ghc2/inplace/bin/ghc-stage2 --interactive Bug.hs GHCi, version 8.1.20170223: http://www.haskell.org/ghc/ :? for help Loaded GHCi configuration from /home/rgscott/.ghci [1 of 1] Compiling DataCast ( Bug.hs, interpreted ) Bug.hs:28:29: error: • Could not deduce (Typeable T) arising from a use of ‘gcast1’ GHC can't yet do polykinded Typeable (T :: * -> *) from the context: (Typeable k, Typeable t, Typeable phantom, Possibly Data phantom) bound by the type signature for: dataCast1T :: (Typeable k, Typeable t, Typeable phantom, Possibly Data phantom) => (forall d. Data d => c (t d)) -> Maybe (c (T phantom)) at Bug.hs:(22,1)-(25,35) or from: (k ~ *, (phantom :: k) ~~ (x :: *), Data x) bound by a pattern with constructor: D :: forall k (p :: k -> Constraint) (x :: k). p x => D p x, in a case alternative at Bug.hs:28:23 • In the expression: gcast1 f In a case alternative: Just D -> gcast1 f In the expression: case possibly (Proxy :: Proxy Data) (Proxy :: Proxy phantom) of Nothing -> Nothing Just D -> gcast1 f | 28 | Just D -> gcast1 f | ^^^^^^^^ }}} That error message itself is hilariously strange, since GHC certainly has the power to do polykinded `Typeable` nowadays. Marking as high priority since this is a regression—feel free to lower the priority if you disagree. -- -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: (none) Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Resolution: | 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: | -------------------------------------+------------------------------------- Comment (by RyanGlScott): I've observed something even stranger about this program. Let's tweak it slightly and add a couple more things (note that the definition of `dataCast1T` is unchanged): {{{#!hs {-# LANGUAGE ConstraintKinds #-} {-# LANGUAGE FlexibleContexts #-} {-# LANGUAGE GADTs #-} {-# LANGUAGE MultiParamTypeClasses #-} {-# LANGUAGE RankNTypes #-} {-# LANGUAGE ScopedTypeVariables #-} {-# LANGUAGE TypeInType #-} {-# LANGUAGE TypeOperators #-} module DataCast where import Data.Data import GHC.Exts (Constraint) data T (phantom :: k) = T data D (p :: k -> Constraint) (x :: j) where D :: forall (p :: k -> Constraint) (x :: k). p x => D p x class Possibly p x where possibly :: proxy1 p -> proxy2 x -> Maybe (D p x) instance Possibly Data () where possibly _ _ = Just D dataCast1T :: forall k c t (phantom :: k). (Typeable k, Typeable t, Typeable phantom, Possibly Data phantom) => (forall d. Data d => c (t d)) -> Maybe (c (T phantom)) dataCast1T f = case possibly (Proxy :: Proxy Data) (Proxy :: Proxy phantom) of Nothing -> Nothing Just D -> gcast1 f newtype Q q x = Q { unQ :: x -> q } ext1Q :: (Typeable k, Typeable t, Typeable (phantom :: k), Possibly Data phantom) => (T phantom -> q) -> (forall e. Data e => t e -> q) -> T phantom -> q ext1Q def ext arg = case dataCast1T (Q ext) of Just (Q ext') -> ext' arg Nothing -> def arg }}} With GHC HEAD, this gives the same error as the original program. But if you add this one definition to this file: {{{#!hs test1 :: Char test1 = (const 'p') `ext1Q` (\T -> 'q') $ (T :: T ()) }}} Then it typechecks without issue on GHC HEAD! This is pretty bizarre, considering that the error was originally reported in `dataCast1T`, and we managed to make the error go away without making a single change to `dataCast1T`. FWIW, this program also compiles without issue on GHC 8.0.2 (with and without `test1`). -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: (none) Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Resolution: | Keywords: typeable 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: | -------------------------------------+------------------------------------- Changes (by bgamari): * keywords: => typeable -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: bgamari Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Resolution: | Keywords: typeable 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: | -------------------------------------+------------------------------------- Changes (by bgamari): * owner: (none) => bgamari -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: bgamari Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Resolution: | Keywords: typeable 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: | -------------------------------------+------------------------------------- Comment (by bgamari): Looking at `-ddump-tc-trace` from the program in the ticket description, it seems that we are failing to solve for this, {{{ WC {wc_simple = [WD] $dTypeable_a29a {0}:: Typeable (T |> Trans (Sym cobox ->_N <*>_N) (cobox ->_N <*>_N)) (CDictCan)} }}} I believe the reason for this is that we don't handle casts in the `Typeable` solver. I'll need to think about this. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: bgamari Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Resolution: | Keywords: typeable 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: | -------------------------------------+------------------------------------- Comment (by simonpj): I think that if we have `t :: k1` and `c :: k1 ~ k2` and {{{ Constraints: [W] c :: Typeable k2 (t |> c) }}} then we can simplify the wanted constraint to {{{ Bindings: c = c1 |> Typeable ?? c Constraints: [W] c1 :: Typeable k1 t }}} Richard do you agree? What is the `??`? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: bgamari Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Resolution: | Keywords: typeable 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: | -------------------------------------+------------------------------------- Comment (by simonpj): Also what if we have {{{ Eq (t |> c) }}} Can we solve that, or do we get stuck? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: bgamari Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Resolution: | Keywords: typeable 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: | -------------------------------------+------------------------------------- Comment (by goldfire): I have a solution in progress. But no time to finish now. Soon. It involves adding a case for casts in `matchTypeable`. Not hard. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:8 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: bgamari Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Resolution: | Keywords: typeable Operating System: Unknown/Multiple | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D3424 Wiki Page: | -------------------------------------+------------------------------------- Changes (by goldfire): * differential: => Phab:D3424 Comment: I now think I know what's going on here, but unsure the best way to fix it. Interestingly, the problem has nothing to do with `Typeable` or `TypeInType`. Indeed it's amazing we've never hit this problem before. We have {{{ [G] c1 :: k1[tau] ~ j1[tau] }}} in an implication. Both `k1` and `j1` are filled in at this point: `k1 := Type` and `j1 := k2[sk]`. This constraint is then passed through `solveSimpleGivens`, where it is canonicalized. `can_eq_nc'` flattens both sides, following both `k1` and `j1` to find `Type`. `can_eq_nc'` then calls `rewriteEqEvidence` which creates a new {{{ [G] c2 :: Type ~ k2[sk] }}} Of course, GHC produces evidence for `c2`: `c2 = g1 ; c1 ; g2`, where `g1` and `g2` are the coercions that come from flattening `k1` and `j1`. The problem is that these coercions, `g1` and `g2` are both reflexive, as they arise simply from zonking. See the line of code [https://github.com/ghc/ghc/blob/master/compiler/typecheck/TcFlatten.hs#L1288 here]. When `c2` is stitched together from `g1`, `c1`, and `g2`, the calls to `mkTcTransCo` notice that some of the arguments are `Refl`, and so ignores the reflexive arguments. The end result is that `c2 = c1`. And then, when `c2` gets put in the inert set, its kind still mentions unzonked variables. (Even though the associated `ctPred` is just fine.) What to do? Here are some ideas: 1. Stop `mkTcTransCo` (but not `mkTransCo`) from optimizing this case. 2. Add a zonk somewhere (`addInertEq`? seems better than `rewriteEqEvidence`) to fix this problem. 3. Add a new coercion form `ZonkCo` that relates an unzonked tyvar to its contents. This way, we can have the invariant that, whenever `(ty', co) <- flatten ty`, we have `co :: ty' ~ ty`. (Right now, that final equality is true only modulo zonking. But the new `ZonkCo` would allow it to be true without needing to zonk.) In fully-typechecked Core, `ZonkCo` would zonk to become reflexive, and so Core would have no `ZonkCo`s. 4. Add a new `castTcCoercion` function that stitches three coercions together using transitivity; this `castTcCoercion` would cleverly not optimize the `Refl` away. I favor (1) but am worried about performance implications. (3) is probably the most principled, but it seems like a sledgehammer to tap in a nail. (4) is a middle ground, but I'm worried that what's happening here (a coercion returned from the flattener having an unzonked kind) happens elsewhere where we wouldn't use `castTcCoercion`. What are your thoughts? (NB: The patch linked to here does not have any of these fixes. I posted that patch some time ago but never added the link from this ticket.) -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:9 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: bgamari Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Resolution: | Keywords: typeable Operating System: Unknown/Multiple | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D3424 Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj):
The end result is that c2 = c1. And then, when c2 gets put in the inert set, its kind still mentions unzonked variables. (Even though the associated ctPred is just fine.)
I don't see the problem. See `Note [Ct/evidence invariant]` in `TcRnTypes`. The types in evidence terms are no zonked, and that should not matter one whit. Can you explain more precisely what actually goes wrong and why? Simon -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:10 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: bgamari Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Resolution: | Keywords: typeable Operating System: Unknown/Multiple | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D3424 Wiki Page: | -------------------------------------+------------------------------------- Comment (by goldfire): It turns out that Note is no longer true. See Phab:D3424 for more explanation. There are validation failures there I have not investigated yet. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:11 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: bgamari Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Resolution: | Keywords: typeable Operating System: Unknown/Multiple | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D3424 Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj): I'm sorry, but I still don't get it. Why don't we fix the bug that makes the Note untrue? I do not understand why it's bad for an evidence term (which the constraint solver never looks at) to be Refl, if it relates two types that are equal after zonking. Your diagnosis concludes
And then, when c2 gets put in the inert set, its kind still mentions unzonked variables.
But you do not say why that matters. I think it should not matter. Can you explain more precisely what goes wrong and why? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:12 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: goldfire Type: bug | Status: new Priority: highest | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Resolution: | Keywords: typeable Operating System: Unknown/Multiple | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D3424 Wiki Page: | -------------------------------------+------------------------------------- Changes (by bgamari): * owner: bgamari => goldfire * priority: high => highest Comment: Bumping the priority of this; I don't think we'll want to cut an 8.2-rc2 until this is fixed. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:13 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: goldfire Type: bug | Status: new Priority: highest | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Keywords: typeable, Resolution: | TypeInType Operating System: Unknown/Multiple | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D3424 Wiki Page: | -------------------------------------+------------------------------------- Changes (by simonpj): * keywords: typeable => typeable, TypeInType -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:14 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: goldfire Type: bug | Status: patch Priority: highest | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Keywords: typeable, Resolution: | TypeInType Operating System: Unknown/Multiple | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D3424 Wiki Page: | -------------------------------------+------------------------------------- Changes (by bgamari): * status: new => patch -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:15 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD
-------------------------------------+-------------------------------------
Reporter: RyanGlScott | Owner: goldfire
Type: bug | Status: patch
Priority: highest | Milestone: 8.2.1
Component: Compiler (Type | Version: 8.1
checker) | Keywords: typeable,
Resolution: | TypeInType
Operating System: Unknown/Multiple | Architecture:
Type of failure: GHC rejects | Unknown/Multiple
valid program | Test Case:
Blocked By: | Blocking:
Related Tickets: | Differential Rev(s): Phab:D3424
Wiki Page: |
-------------------------------------+-------------------------------------
Comment (by Ben Gamari
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: goldfire Type: bug | Status: merge Priority: highest | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Keywords: typeable, Resolution: | TypeInType Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: GHC rejects | Test Case: valid program | typecheck/should_compile/T13333 Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D3424 Wiki Page: | -------------------------------------+------------------------------------- Changes (by goldfire): * testcase: => typecheck/should_compile/T13333 * status: patch => merge Comment: Thanks for pushing this, Ben! -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:17 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: goldfire Type: bug | Status: closed Priority: highest | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Keywords: typeable, Resolution: fixed | TypeInType Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: GHC rejects | Test Case: valid program | typecheck/should_compile/T13333 Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D3424 Wiki Page: | -------------------------------------+------------------------------------- Changes (by bgamari): * status: merge => closed * resolution: => fixed Comment: Merged to `ghc-8.2` as 51d80c3b2c4c7d8f1f5dbcee39864c2de49143c7. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:18 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
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