Status of inline type annotations

Question

I've been using Eclipse/Zend type annotations for years to help editor's code intellisense where regular phpDocumentor docblocks do not suffice:

/* @var $db PDO */
$db->exec('DELETE FROM pending_jobs');

… but I'm not sure they're widely used nowadays.

PHP-FIG proposed a new syntax for this feature in the context of PSR-5 PHPDoc Standard:

/** @var PDO $db Database connection. */

… but PSR-5 is listed as abandoned and as far as I can tell phpDocumentor hasn't implemented it.

PhpStorm just supports all variations:

/* @var $db PDO */
/* @var PDO $db */
/** @var PDO $db */
/** @var $db PDO */

Even Zend Framework codebase seems to mix them all.

Is there a widespread syntax or something close to a de-facto standard? Has it been subject to discussions in some major PHP projects?