Compilation to GO produces broken code

namespace go reports

typedef string ReportState
const ReportState ReportStateQueued = "QUEUED";
const ReportState ReportStateCalculating = "CALCULATING";
const ReportState ReportStateImporting = "IMPORTING";
const ReportState ReportStateFinished = "FINISHED";
const ReportState ReportStateFailed = "FAILED";

struct ReportFilter {
    1: i64 quantity,
    2: i64 dataVersion,
    3: string subscriptionID,
    4: optional string principalID,
    5: optional string createdOn,
    6: optional list<ReportState> states,
}

func (p *ReportFilter)  ReadField6(iprot thrift.TProtocol) error {
  _, size, err := iprot.ReadListBegin()
  if err != nil {
    return thrift.PrependError("error reading list begin: ", err)
  }
  tSlice := make([]ReportState, 0, size)
  p.States =  tSlice
  for i := 0; i < size; i ++ {
var _elem0 string
    if v, err := iprot.ReadString(); err != nil {
    return thrift.PrependError("error reading field 0: ", err)
} else {
    _elem0 = v
}
    p.States = append(p.States, _elem0)
  }
  if err := iprot.ReadListEnd(); err != nil {
    return thrift.PrependError("error reading list end: ", err)
  }
  return nil
}

cannot use _elem0 (type string) as type ReportState in append

 p.States = append(p.States, _elem0)