Bug report

This is a duplicate of #1251, but with a better use case.

phpstan reports Casting to int something that's already an int even when the something has a possibility of not being an int.

In my case this occurs with bindec, which has a documented return type of float|int, and I need to guarantee that it's an int, so I'm casting it (it's safe because I'm also limiting the input size to 3 hex chars, so it will never actually hit the overflow that would cause it to return a float).

The cast is also needed for other type checkers such as psalm.

Code snippet that reproduces the problem

$chunk = '123';
$offset = (int)bindec(base_convert($chunk, 16, 2));

phpstan's opinion would be correct if it could know all possible values of $chunk, but that's hard to know. For example FFFFFFFFFFFFFFFF would return an int from bindec, but FFFFFFFFFFFFFFFFF would return a float.

Expected output

No error