Column containing non-vector values can be modified to VECTOR type without warnings

MariaDB [test]> create table t (a blob);

Query OK, 0 rows affected (0.033 sec)

MariaDB [test]> insert into t values (1),(2);

Query OK, 2 rows affected (0.013 sec)

Records: 2  Duplicates: 0  Warnings: 0

MariaDB [test]> alter table t modify a vector(100);

Query OK, 2 rows affected (0.078 sec)                      

Records: 2  Duplicates: 0  Warnings: 0

MariaDB [test]> insert into t values (1),(2);

ERROR 4078 (HY000): Cannot cast 'int' as 'vector' in assignment of `test`.`t`.`a`

MariaDB [test]> select vec_totext(a) from t\G

*************************** 1. row ***************************

vec_totext(a): [-8084406208738727000000000000000000000.000000,0.000000,...]

*************************** 2. row ***************************

vec_totext(a): [-12181128430122706000000000000000000000.000000,0.000000,...]

2 rows in set (0.001 sec)

MariaDB [test]> create table ts (a blob);

Query OK, 0 rows affected (0.033 sec)

MariaDB [test]> insert into ts values (1),(2);

Query OK, 2 rows affected (0.014 sec)

Records: 2  Duplicates: 0  Warnings: 0

MariaDB [test]> alter table ts modify a geometry;

ERROR 1416 (22003): Cannot get geometry object from data you send to the GEOMETRY field