xmlserialize problems in direct mode
For demo, PLS create table
CREATE TABLE XML_TEST
(
  ID NUMBER (9,0) NOT NULL,
  XML_COL XMLTYPE
)
/
ALTER TABLE XML_TEST ADD
(
  CONSTRAINT XML_TEST_PK
  PRIMARY KEY
  (
    ID
  )
/
You don't need any data to reproduce.
Create a new 64-bit application and add TOraSession, TSmartQuery, TOraDatascource and a grid components.
Connect to Oracle using Direct mode
Use the following SQL:
SELECT /*+FIRST_ROWS*/ "ID", xmlserialize( content"XML_COL") "XML_COL"
FROM XML_TEST  T
Open or prepare the query.
You will get several assertion violations, error messages and access violation errors.