No match in record selector Var.tcTyVarDetails with ghc >= 6.10.2
This seems to have been introduced in 6.10.2:
{-# OPTIONS_GHC -fglasgow-exts #-}
{-# LANGUAGE UndecidableInstances #-}
module Bug where
newtype Trie m k a = Trie (Maybe a, m (SubKey k) (Trie m k a))
type family SubKey k
type instance SubKey [k] = k
deriving instance (Eq (m k (Trie m [k] a))
,Eq a) => Eq (Trie m [k] a)
which fails with:
[m@monire ~]$ ghc -O2 -c --make Bug.hs
[1 of 1] Compiling Bug ( Bug.hs, Bug.o )
ghc: panic! (the 'impossible' happened)
(GHC version 6.10.3 for x86_64-unknown-linux):
No match in record selector Var.tcTyVarDetails
Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug
Matt
Trac metadata
Trac field | Value |
---|---|
Version | 6.10.4 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |