Exported structs and globals are marked as unused

[Thunkar]

Aim

#[abi(notes)]
global note_export: (Field, Field) = (123, 124);

#[abi(functions)] 
struct MyFnAbi {
    parameters: MyFnParameters,
    return_value: Field,
}

This code generates warnings for unused structs and globals

Expected Behavior

Being able to generate the exports without warnings being emitted

Bug

Warnings are generated

To Reproduce

Use the example above

Workaround

None

Workaround Description

No response

Additional Context

No response

Project Impact

None

Blocker Context

No response

Nargo Version

No response

NoirJS Version

No response

Proving Backend Tooling & Version

No response

Would you like to submit a PR for this Issue?

None

Support Needs

No response

[TomAFrench]

@asterite Are we marking structs as unused before macros run?

[TomAFrench]

Ah, nvm. This is a different kind of exported.

[asterite]

So is the rule that if there's #[abi(...)]` on top of a struct then it shouldn't warn if it's unused?

[TomAFrench]

Yeah, this annotation marks that we should create a template for that struct type in the ABI. Similarly for globals, it puts the value of those in the ABI.

[asterite]

In the example above, I guess MyFnParameters would also be considered used because it's inside a struct that's marked with #[abi]?

[TomAFrench]

Yeah, we should mark anything reachable from these structs as used.