//
	// It must be possible for importers to construct such invalid interfaces.
	// Previously, this panicked.

	sig1 := NewSignatureType(nil, nil, nil, NewTuple(NewParam(nopos, nil, "", Typ[Int])), nil, false)
	sig2 := NewSignatureType(nil, nil, nil, NewTuple(NewParam(nopos, nil, "", Typ[String])), nil, false)

	methods := []*Func{
		NewFunc(nopos, nil, "M", sig1),
		NewFunc(nopos, nil, "M", sig2),
	}