Compiler panics on "phantom family"
Feeding the following innocent looking (well...) program into GHC causes the compiler to panic:
{-# OPTIONS_GHC -fglasgow-exts #-}
type family KUnit a :: *
type instance KUnit Int = ()
unit :: KUnit Int
unit = ()
The cry for help reads:
ghc-6.8.20071007: panic! (the 'impossible' happened)
(GHC version 6.9.20070923 for powerpc-apple-darwin):
check_tau_type main:Main.KUnit{tc rnu} base:GHC.Base.Int{(w) tc 3J}
Unsurprisingly, I've experienced the same behaviour with 6.9.20070923.
HTH,
Stefan Holdermans
Trac metadata
Trac field | Value |
---|---|
Version | 6.8 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler (Type checker) |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | abaars@iti.upv.es, stefan@cs.uu.nl |
Operating system | Multiple |
Architecture | Unknown |