Name is reported as ambiguous and not in scope

module A where

data T = A

module B where

import A

data S = A

foo :: A -> ()
foo = undefined

Compiling this example, the usage of A in foo is reported as both ambiguous and out of scope.

I haven't mentioned data kinds at all so A should certainly refer to a type constructor which isn't in scope. The problem is that DataKinds is checked too late in lookup_demoted.

Trac metadata

Trac field	Value
Version	8.0.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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