Parameter array with SQL_C_TYPE_DATE fails with "Error while retrieving parameter from callback function" (PCALLBACK=1)

An INSERT executed with a parameter array (SQL_ATTR_PARAMSET_SIZE > 1) fails if one of the parameters is bound as SQL_C_TYPE_DATE (or SQL_C_DATE):

[HY000] [ma-3.2.10][11.8.9-MariaDB-ubu2404]Error while retrieving parameter from callback function

No row is inserted. With PCALLBACK=0 in the DSN the same program inserts all rows correctly. SQL_C_TYPE_TIMESTAMP arrays, and SQL_C_TYPE_DATE in a single row execute, work.

Steps to reproduce (program attached, date.c):

1. CREATE TABLE odbc_date_arr (id INT, d DATE)
2. SQLPrepare "INSERT INTO odbc_date_arr (id, d) VALUES (?, ?)"
3. SQL_ATTR_PARAM_BIND_TYPE = SQL_PARAM_BIND_BY_COLUMN, SQL_ATTR_PARAMSET_SIZE = 3
4. SQLBindParameter 1: SQL_C_LONG / SQL_INTEGER, SQLINTEGER[3]
5. SQLBindParameter 2: SQL_C_TYPE_DATE / SQL_TYPE_DATE, column size 10, SQL_DATE_STRUCT[3] {2026-02-01, 2026-02-02, 1999-12-31}

   , indicators 0

6. SQLExecute

gcc -o date date.c -lodbc

./date <DSN> <user> <password>

PCALLBACK=1 (default), 3.2.6 and 3.2.10:

SQLExecute (3 rows): rc=-1 [HY000] [ma-3.2.10][11.8.9-MariaDB-ubu2404]Error while retrieving parameter from callback function

rows inserted: 0 (expected 3)

PCALLBACK=0:

SQLExecute (3 rows): rc=0

rows inserted: 3 (expected 3)

The same happens with NULL indicators in some rows. Possibly related: CONC-623 (return code of the parameter callback).

Workaround: PCALLBACK=0 in the DSN.

The analysis and the test program were made with AI assistance (Claude); I have verified the results.