#7280: zonkQuantifiedTyVar panic
------------------------------+---------------------------------------------
Reporter: rl | Owner:
Type: bug | Status: new
Priority: normal | Component: Compiler
Version: 7.6.1 | Keywords:
Os: Unknown/Multiple | Architecture: Unknown/Multiple
Failure: None/Unknown | Testcase:
Blockedby: | Blocking:
Related: |
------------------------------+---------------------------------------------
Small program (extracted from the dev version of vector):
{{{
{-# LANGUAGE Rank2Types, MultiParamTypeClasses, FlexibleContexts,
TypeFamilies, ScopedTypeVariables #-}
module T where
type family Mutable (v :: * -> *) :: * -> * -> *
class MVector (v :: * -> * -> *) a
class MVector (Mutable v) a => Vector v a where
copy :: Monad m => Mutable v s a -> v a -> m ()
data Chunk v s a = Chunk (forall m. (Monad m, Vector v a) => Mutable v s a
-> m ())
vstep (v:vs) = Chunk (\mv -> copy mv v)
}}}
When I compile this, I get:
{{{
ghc: panic! (the 'impossible' happened)
(GHC version 7.6.1 for x86_64-unknown-linux):
zonkQuantifiedTyVar f_afr{tv} [fsk]
}}}
--
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7280>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler
_______________________________________________
Glasgow-haskell-bugs mailing list
Glasgow-haskell-bugs@haskell.org
http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
