Does edk2 also link to crt0-efi like GNU-EFI

["Ayush Singh" <ayushdevel1325@gmail.com>]

Hello everyone, I wanted to ask if the edk2 build system also links to
crt0-efi, like GNU-EFI?

If yes, I would also like to see how that is actually implemented. If
not, how does edk2 support custom entry functions? It is possible with
llvm backend but I am not sure how it is done in GCC and am curious,

Currently, rust does not support the custom implementation of
`lang_start` (which is started by crt0 in most platforms), so I was
trying to find ways to be able to use custom crt0 which sets up
`SystemTable` and `SystemHandler` and start the `lang_start` from it.
This way, the user will be able to call the normal `main` function
rather than using the `no_main` feature.

My blog post [1] shows how we currently use the `efi_main` function.

Yours sincerely,
Ayush Singh

[1]: (https://www.programmershideaway.xyz/post5/)