ORA-14552 and Oracle Function

ORA-14552: cannot perform a DDL, commit or rollback inside a query or DML
    Cause: DDL operations like creation tables, views etc. and transaction control statements such as commit/rollback cannot be performed inside a query or a DML statement.
    Action: Ensure that the offending operation is not performed or use autonomous transactions to perform the operation within the query/DML operation.

eg:
CREATE OR REPLACE FUNCTION OSM_DML_3SP.OSM_TAB_FUNCFUNC1(t IN INTEGER)
  RETURN INTEGER IS rt INTEGER;
  col0 OSM_TAB_FUNC.COL_0%TYPE := 48;
BEGIN
  SAVEPOINT do_del;
  DELETE FROM OSM_DML_3SP.OSM_TAB_FUNC WHERE COL_0 < col0+t;

  IF SQL%FOUND THEN
    ROLLBACK TO do_del;
    INSERT INTO OSM_DML_3SP.OSM_TAB_FUNC SELECT * FROM OSM_DML_3SP.OSM_TAB_FUNC;
    COMMIT COMMENT 'Insert data two times.';
  END IF;

  SELECT COUNT(*) INTO rt FROM OSM_DML_3SP.OSM_TAB_FUNC;
  RETURN rt;
END;

-- this is the correct write
DECLARE
  CURSOR c1(tc VARCHAR2) IS SELECT COL_0 FROM OSM_DML_3SP.OSM_TAB_FUNC
    WHERE COL_3 LIKE '%'||tc||'%';
  rfunt INTEGER;
BEGIN
  FOR tc IN c1('6') LOOP
    rfunt := OSM_DML_3SP.OSM_TAB_FUNCFUNC1(52);
    UPDATE OSM_DML_3SP.OSM_TAB_FUNC SET COL_0=rfunt WHERE COL_0=tc.COL_0;
  END LOOP;
END;
/

-- this is the error write
DECLARE
  CURSOR c1(tc VARCHAR2) IS SELECT COL_0 FROM OSM_DML_3SP.OSM_TAB_FUNC
    WHERE COL_3 LIKE '%'||tc||'%';
BEGIN
  FOR tc IN c1('6') LOOP
    UPDATE OSM_DML_3SP.OSM_TAB_FUNC SET COL_0=OSM_DML_3SP.OSM_TAB_FUNCFUNC1(52)
      WHERE COL_0=tc.COL_0;
  END LOOP;
END;
/

ORA-14552: cannot perform a DDL, commit or rollback inside a query or DML
ORA-06512: at "OSM_DML_3SP.OSM_TAB_FUNCFUNC1", line 1
ORA-06512: at line 1