Type roles in GHCi

This works:

λ> data A a; type role A nominal
λ> :i A
type role A nominal
data A a

This doesn't:

λ> data A a
λ> type role A nominal
λ> :i A
type role A phantom
data A a

Accepting role annotations after the definition probably leads to problems when intermediate definitions relied on the earlier role; so I think the second situation should give an error. In fact, in the second snippet GHC does not even require -XRoleAnnotations.

Trac metadata

Trac field	Value
Version	7.7
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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CC	goldfire
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Architecture