var data [3]int
	// By coincidence all of these fields are ints, which simplifies things.
	v := reflect.ValueOf(err)
	for i, name := range []string{"go116code", "go116start", "go116end"} {
		f := v.FieldByName(name)
		if !f.IsValid() {
			return 0, 0, 0, false
		}
		data[i] = int(f.Int())
	}
	return ErrorCode(data[0]), token.Pos(data[1]), token.Pos(data[2]), true

	}

	span := spanOf(posn)
	e := Error{
		Fset:       check.fset,
		Pos:        span.pos,
		Msg:        stripAnnotations(msg),
		Soft:       soft,
		go116code:  code,
		go116start: span.start,
		go116end:   span.end,
	}

	if check.errpos != nil {
		// If we have an internal error and the errpos override is set, use it to
		// augment our error positioning.

	// to preview this feature may read go116code using reflection (see
	// errorcodes_test.go), but beware that there is no guarantee of future
	// compatibility.
	go116code  Code
	go116start token.Pos
	go116end   token.Pos
}

// Error returns an error string formatted as follows:
// filename:line:column: message
func (err Error) Error() string {
	return fmt.Sprintf("%s: %s", err.Fset.Position(err.Pos), err.Msg)
}