[GHC] #12668: Program that fails Core Lint terribly
#12668: Program that fails Core Lint terribly -------------------------------------+------------------------------------- Reporter: bgamari | Owner: Type: bug | Status: new Priority: normal | Milestone: 8.2.1 Component: Compiler | Version: 8.1 (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: -------------------------------------+------------------------------------- While looking for a testcase for another unrelated compiler bug (see Phab:D2577) I had the pleasure of encountering this specimen, {{{#!hs {-# LANGUAGE TypeInType #-} {-# LANGUAGE RankNTypes #-} module Hi where import GHC.Exts data Some r = Some (TYPE r -> TYPE r) doSomething :: forall (r :: RuntimeRep). forall (a :: TYPE r). () => Int -> (a -> Int) -> a -> a doSomething n f = case n of 1 -> error "hello" 3 -> error "hello" }}} GHC 465c6c5d15f8fb54afb78408f3a79e75e74d2cd4 seems to let this program typecheck, but if you enable Core Lint it soon becomes clear that not all is well. Here's a sampling of the carnage, {{{ $ ghc hi.hs -fforce-recomp -dcore-lint -O0 [1 of 1] Compiling Hi ( hi.hs, hi.o ) *** Core Lint errors : in result of Desugar (after optimization) *** <no location info>: warning: In the type ‘a_a2ON -> Int’ Ill-kinded argument in type or kind ‘a_a2ON -> Int’ type or kind ‘a_a2ON -> Int’ kind: TYPE r_a2OM <no location info>: warning: In the type ‘a_a2ON -> a_a2ON’ Ill-kinded argument in type or kind ‘a_a2ON -> a_a2ON’ type or kind ‘a_a2ON -> a_a2ON’ kind: TYPE r_a2OM <no location info>: warning: In the type ‘a_a2ON -> a_a2ON’ Ill-kinded argument in type or kind ‘a_a2ON -> a_a2ON’ type or kind ‘a_a2ON -> a_a2ON’ kind: TYPE r_a2OM <no location info>: warning: In the expression: patError @ 'PtrRepLifted @ (a_a2ON -> a_a2ON) "hi.hs:(12,5)-(14,24)|case"# Ill-kinded argument in type or kind ‘a_a2ON -> a_a2ON’ type or kind ‘a_a2ON -> a_a2ON’ kind: TYPE r_a2OM ... }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12668 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12668: Program that fails Core Lint terribly -------------------------------------+------------------------------------- Reporter: bgamari | Owner: Type: bug | Status: new Priority: normal | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | 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: | -------------------------------------+------------------------------------- Description changed by bgamari: @@ -21,3 +21,3 @@ - GHC 465c6c5d15f8fb54afb78408f3a79e75e74d2cd4 seems to let this program - typecheck, but if you enable Core Lint it soon becomes clear that not all - is well. Here's a sampling of the carnage, + GHC 465c6c5d15f8fb54afb78408f3a79e75e74d2cd4 and 8.0.1 seem to let this + program typecheck, but if you enable Core Lint it soon becomes clear that + not all is well. Here's a sampling of the carnage, New description: While looking for a testcase for another unrelated compiler bug (see Phab:D2577) I had the pleasure of encountering this specimen, {{{#!hs {-# LANGUAGE TypeInType #-} {-# LANGUAGE RankNTypes #-} module Hi where import GHC.Exts data Some r = Some (TYPE r -> TYPE r) doSomething :: forall (r :: RuntimeRep). forall (a :: TYPE r). () => Int -> (a -> Int) -> a -> a doSomething n f = case n of 1 -> error "hello" 3 -> error "hello" }}} GHC 465c6c5d15f8fb54afb78408f3a79e75e74d2cd4 and 8.0.1 seem to let this program typecheck, but if you enable Core Lint it soon becomes clear that not all is well. Here's a sampling of the carnage, {{{ $ ghc hi.hs -fforce-recomp -dcore-lint -O0 [1 of 1] Compiling Hi ( hi.hs, hi.o ) *** Core Lint errors : in result of Desugar (after optimization) *** <no location info>: warning: In the type ‘a_a2ON -> Int’ Ill-kinded argument in type or kind ‘a_a2ON -> Int’ type or kind ‘a_a2ON -> Int’ kind: TYPE r_a2OM <no location info>: warning: In the type ‘a_a2ON -> a_a2ON’ Ill-kinded argument in type or kind ‘a_a2ON -> a_a2ON’ type or kind ‘a_a2ON -> a_a2ON’ kind: TYPE r_a2OM <no location info>: warning: In the type ‘a_a2ON -> a_a2ON’ Ill-kinded argument in type or kind ‘a_a2ON -> a_a2ON’ type or kind ‘a_a2ON -> a_a2ON’ kind: TYPE r_a2OM <no location info>: warning: In the expression: patError @ 'PtrRepLifted @ (a_a2ON -> a_a2ON) "hi.hs:(12,5)-(14,24)|case"# Ill-kinded argument in type or kind ‘a_a2ON -> a_a2ON’ type or kind ‘a_a2ON -> a_a2ON’ kind: TYPE r_a2OM ... }}} -- -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12668#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12668: Program that fails Core Lint terribly -------------------------------------+------------------------------------- Reporter: bgamari | Owner: Type: bug | Status: new Priority: normal | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | 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: | -------------------------------------+------------------------------------- Comment (by goldfire): What's wrong here? My first worry is that Core Lint is doing the wrong thing. And does your `Some` type enter the picture? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12668#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
What's wrong here? My first worry is that Core Lint is doing the wrong
#12668: Program that fails Core Lint terribly -------------------------------------+------------------------------------- Reporter: bgamari | Owner: Type: bug | Status: new Priority: normal | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | 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: | -------------------------------------+------------------------------------- Comment (by bgamari): thing. I'm afraid I didn't look much farther; I was hoping I'd be able to quickly get the `typeable` branch rebased between builds on another project; sadly the yaks just keep piling up.
And does your Some type enter the picture?
Indeed I suspect it doesn't. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12668#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12668: Program that fails Core Lint terribly
-------------------------------------+-------------------------------------
Reporter: bgamari | Owner:
Type: bug | Status: new
Priority: normal | Milestone: 8.2.1
Component: Compiler (Type | Version: 8.1
checker) |
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: |
-------------------------------------+-------------------------------------
Comment (by Simon Peyton Jones
#12668: Program that fails Core Lint terribly -------------------------------------+------------------------------------- Reporter: bgamari | Owner: Type: bug | Status: closed Priority: normal | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Resolution: fixed | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: | polykinds/T12668 Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by simonpj): * status: new => closed * testcase: => polykinds/T12668 * resolution: => fixed -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12668#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12668: Program that fails Core Lint terribly -------------------------------------+------------------------------------- Reporter: bgamari | Owner: Type: bug | Status: closed Priority: normal | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Keywords: Resolution: fixed | LevityPolymorphism Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: | polykinds/T12668 Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by bgamari): * keywords: => LevityPolymorphism -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12668#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
participants (1)
-
GHC