T17355.hs:9:10: error: [GHC-91510]
    • Illegal polymorphic type: forall a. a
    • In the instance declaration for ‘Generic (forall a. a)’

T17355.hs:10:10: error: [GHC-91510]
    • Illegal polymorphic type: forall a. a -> a
    • In the instance declaration for
        ‘HasField "myPoly" Foo (forall a. a -> a)’