PHP 7.4, Debian 10

PHP upstream attempt at bypassing version based tests and relying on syntax errors to identify transaction features not supported by very old MySQL/MariaDB versions:

https://github.com/php/php-src/pull/5877

A wider look at how MariaDB does versioning in light of the 5.5 EOL is still needed. I seem to remember/assume that the versioning was around cross MySQL replica / MariaDB master replication giving a id that MySQL identifies. How this requirement exists currently is probably open to re-evaluation.

So this MDEV-4088 related rather than the innodb versioning of MDEV-16172 that was incorrectly assumed in the php bug,

mac89 are you actually experiencing this problem?

The mariadb on docker hub is ubuntu based and very similarly packaged to debian and I don't have a problem.

$ php --version

PHP 7.4.9 (cli) (built: Aug  4 2020 08:28:13) ( NTS )

$  podman run -e MYSQL_USER=dan -e MYSQL_PASSWORD=bob  -e MYSQL_ROOT_PASSWORD=bob -e MYSQL_DATABASE=test  --name mariadb10.3 -p 3306  mariadb:10.3

$ cat /tmp/t.php 

<?php

$db = new mysqli("127.0.0.1", "dan", "bob", "test");

$db->begin_transaction(MYSQLI_TRANS_START_READ_WRITE);

$v = $db->server_version;

print "server version $v\n";

$db->commit();

$db->begin_transaction(MYSQLI_TRANS_START_READ_WRITE);

$v = $db->server_version;

print "server version $v\n";

/tmp 

$ php /tmp/t.php 

server version 100324

server version 100324

So no errors here.

Despite a revert being threatened in https://bugs.php.net/bug.php?id=78179 it didn't happen
https://github.com/php/php-src/blob/master/ext/mysqlnd/mysqlnd_connection.c#L1440

I managed to reproduce this bug report by getting php's mysqli against a mysql's (not mariadb) version of the connector-c library (and mysqlnd was unable to reproduce this too),

I needed to do modifications to the MySQL-8.0.21 build. Maybe mac89 older library actually worked easier.

Either way, still working with php upstream to complete this fix. Using the mysqlnd from php will work around this in the mean time.

Not so much "not a bug" but not our bug.

Fixed in upstream PHP -https://github.com/php/php-src/commit/740f0f616521c5e257f2e9923dadfde3a8352f48