Incorrect type-checking of principal / callable value

[obycode]

In this function, the type-checker should report an error:

(define-trait my-trait ())

(define-read-only (foo (x <my-trait>))
  (is-eq x .bar)
)

There is no error from the type-checker, but there will be an error at runtime:

error: Runtime Error: Runtime error while interpreting ST1PQHQKV0RJXZFY1DGX8MNSNYVE3VGZJSRTPGZGM.contract-4: Unchecked(TypeError(PrincipalType, CallableType(Trait(TraitIdentifier { name: ClarityName("my-trait"), contract_identifier: QualifiedContractIdentifier { issuer: StandardPrincipalData(ST1PQHQKV0RJXZFY1DGX8MNSNYVE3VGZJSRTPGZGM), name: ContractName("sandbox") } }))))