[php-src] Issue #8068: mysqli_fetch_object creating objects with invalid properties

Issue: https://github.com/php/php-src/issues/8068 Author: ras52 ### Description The following code fetches a object with a single property whose name and value is '42'. ```php <?php $dbh = new mysqli('localhost', 'richard'); $res = $dbh->query('SELECT 42'); $obj = $res->fetch_object(); $prop = 42; var_dump($obj); echo ">{$obj->$prop}<\n"; $obj = json_decode(json_encode($obj)); var_dump($obj); echo ">{$obj->$prop}<\n"; ``` This results in this output: ``` object(stdClass)#3 (1) { [42]=> string(2) "42" } PHP Notice: Undefined property: stdClass::$42 in /home/richard/test.php on line 8 >< object(stdClass)#4 (1) { ["42"]=> string(2) "42" } >42< ``` The first var_dump confirms that $obj does contain the expected property. However it is not possible to access it via the $obj->$prop syntax, nor with $obj->{42} or $obj->{'42'}. Transforming it to JSON and back turns it into a more regular object which can be accessed with either of these syntaxes. I expected the >< in the output to read >42<. Changing $res->fetch_object() to (object)$res->fetch_assoc() has the expected effect, and provides an adequate work-around. My guess is that this is another instance of [this bug/oddity that was fixed in PHP 7.2](https://www.php.net/manual/en/migration72.incompatible.php#migration72.incompatible.object-array-casts) that escaped being fixed. Just in case its relevant, I'm testing with MariaDB 10.5.12. ### PHP Version PHP 8.1.2 (also 8.0.15 and 7.4.27) ### Operating System Debian 11