GHC sometimes misses a CUSK
{-# LANGUAGE TypeInType #-}
data Test (a :: x) (b :: x) :: x -> *
where K :: Test Int Bool Doublefails, because GHC thinks that Test does not have a CUSK.
It should have a CUSK, because while there is no forall x in the result kind, the x is in scope from previous use in kinds.
Fix en route.
Trac metadata
| Trac field | Value |
|---|---|
| Version | 8.1 |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | |
| Architecture |