GADT + impredicative polymorphism => stack overflow
The following makes the GHC 6.6 type checker loop/overflow:
{-# OPTIONS_GHC -fglasgow-exts #-}
data Foo a b where F :: a -> Foo () a
bar :: Foo () (forall a.a) -> ()
bar (F _) = ()ghc yields stack overflow, as does ghci. Reloading in GHCi leads to an infinite loop.
Trac metadata
| Trac field | Value |
|---|---|
| Version | 6.6 |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler (Type checker) |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | Unknown |
| Architecture | Unknown |