Cannot add annotation on AliasTypeDef

[joejoe321321]

Hi, the newest rdl cannot generate json correctly when adding annotation after alias type definition.

example rdl:

namespace com.yahoo.apex.parsec;
name apex;
version 1;

type DateTime string (x_date_time)

type Response struct {
DateTime dateTime;
}

If we generate json with the newest rdl, we will get:
*** Error(error.rdl:8): Recursively typed fields must be optional: field 'dateTime' in struct Response

Furthermore, if we put (optional) after field dateTime, the generated json seems not correct, either.

example:
"AliasTypeDef": { "type": "___forward_reference___", "name": "DateTime" }

Is an annotation on alias type still a legal format?
Thank you.