STR_TO_DATE does not work with UCS2/UTF16/UTF32

Description

STR_TO_DATE returns NULL with a warning in case of a correct input
in combination with ucs2, utf16, utf16le, or utf32:

The expected result is: 2001-01-01.

Note, MySQL-5.6 demonstrates the same problem.

Environment

None

Status

Assignee

Alexander Barkov

Reporter

Alexander Barkov

Labels

External issue ID

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External issue ID

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Fix versions

Affects versions

Priority

Major
Configure