[First Draft] Add @gc as a Function Attribute

[Richard (Rikki) Andrew Cattermole]

On 15/06/2024 4:20 AM, Quirin Schroll wrote:
> Permalink: 
> https://github.com/Bolpat/DIPs/blob/8a26c2545b0a6926d799e9d8dc8c3662e58d516b/DIPs/DIP-4NNN-QFS.md
> 
> ---
> 
> **Abstract:** Add `@gc` as a new function attribute that acts as the 
> inverse of the `@nogc` attribute.

At some point I wanted to do a DIP that ensured all attributes had a 
positive form, a common negated syntax ``@!identifier``, changed 
throwing to be set based ``@throws(...)`` and add ``@notls``, 
``@localnogc``.

So I'm in support of this proposal, but it doesn't go anywhere near 
where it needs to in terms of scope.

You're welcome to do the proposal instead as I'm busy on other things 
atm if it interests you.