Bug report

Version: 0.12.83

Whenever I use the splat operator in combination with named arguments in PHP 8 I get the following error when running phpstan.

Offset 'key' does not exist on array<int, mixed>.

Code snippet that reproduces the problem

A failing code snippet can be found here: https://phpstan.org/r/fef73ac6-edb2-4c18-bbf1-953d722e8d5f

As a reference:

<?php declare(strict_types = 1);

class HelloWorld
{
	public function __construct(...$args)
	{
		print($args['hostname']);
	}
}

$hello = new HelloWorld(hostname: 'localhost');

Expected output

To be fair I'm really new to phpstan. @ondrejmirtes asked me to raise this report based on the following discussion: #4849. If I can help with some more information or details, let me know.