incorrect result for user variables of datetime type

[eurekaka]

Development Task

mysql> set @p = now();
Query OK, 0 rows affected (0.00 sec)

mysql> select @p;
+------+
| @p   |
+------+
|      |
+------+
1 row in set (0.00 sec)

[ti-srebot]

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Bug

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1. Root Cause Analysis (RCA) (optional)

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5. Affected versions

[v4.0.9]

6. Fixed versions

4.0.10