Core Lint error with a data type
The following data declaration fails -dcore-lint
{-# LANGUAGE PolyKinds, ExplicitForAll, ExistentialQuantification #-}
module T16221 where
data T0 a = forall k (b :: k). MkT0 (T0 b) !Int
The test case was extracted from T14066a, the bang is to force the data type to have a wrapper. This has been present at least since GHC 8.0.
<no location info>: warning:
In the type ‘T0 a_a1wY’
Kind application error in type ‘T0 a_a1wY’
Function kind = forall k. k -> *
Arg kinds = [(k_X1x2, *), (a_a1wY, k_a1wZ)]
Fun: k_X1x2
(a_a1wY, k_a1wZ)
<no location info>: warning:
In the expression: MkT0
@ k_X1x2 @ a_a1wY @ k_X1x2 @ b_a1x0 dt_a1xC dt_X1xK
Kinds don't match in type application:
Type variable: a_X1xw :: k_X1x2
Arg type: a_a1wY :: k_a1wZ
Linted Arg kind: k_a1wZ
<no location info>: warning:
In the type ‘T0 a_a1wY’
Kind application error in type ‘T0 a_a1wY’
Function kind = forall k. k -> *
Arg kinds = [(k_X1x2, *), (a_a1wY, k_a1wZ)]
Fun: k_X1x2
(a_a1wY, k_a1wZ)
<no location info>: warning:
In the expression: MkT0
@ k_X1x2 @ a_a1wY @ k_X1x2 @ b_a1x0 dt_a1xC dt_X1xK
Kinds don't match in type application:
Type variable: a_X1xw :: k_X1x2
Arg type: a_a1wY :: k_a1wZ
Linted Arg kind: k_a1wZ
Trac metadata
Trac field | Value |
---|---|
Version | 8.7 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler (Type checker) |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |