Description:
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We're now annotating internal functions[1]:

> Lack of type information for internal functions in Reflection is a long-standing issue. In PHP 8 we finally have all the necessary technical groundwork done to support argument and return type annotations on internal functions at scale.

Scope of this ticket is to actually add that information to the phar functions, using Nikita's exemplar[2] as reference.

[1]:https://externals.io/message/106522
[2]:https://github.com/php/php-src/pull/4499