Re: [PATCH v3 03/13] rust: add derive macro for `Zeroable`

From: Boqun Feng
Date: Sun Jul 30 2023 - 22:52:10 EST


On Sat, Jul 29, 2023 at 09:09:35AM +0000, Benno Lossin wrote:
[...]
> diff --git a/rust/macros/quote.rs b/rust/macros/quote.rs
> index dddbb4e6f4cb..b76c198a4ed5 100644
> --- a/rust/macros/quote.rs
> +++ b/rust/macros/quote.rs
> @@ -124,6 +124,12 @@ macro_rules! quote_spanned {
> ));
> quote_spanned!(@proc $v $span $($tt)*);
> };
> + (@proc $v:ident $span:ident ; $($tt:tt)*) => {
> + $v.push(::proc_macro::TokenTree::Punct(
> + ::proc_macro::Punct::new(';', ::proc_macro::Spacing::Alone)
> + ));
> + quote_spanned!(@proc $v $span $($tt)*);
> + };
> (@proc $v:ident $span:ident $id:ident $($tt:tt)*) => {
> $v.push(::proc_macro::TokenTree::Ident(::proc_macro::Ident::new(stringify!($id), $span)));
> quote_spanned!(@proc $v $span $($tt)*);
> diff --git a/rust/macros/zeroable.rs b/rust/macros/zeroable.rs
> new file mode 100644
> index 000000000000..0d605c46ab3b
> --- /dev/null
> +++ b/rust/macros/zeroable.rs
> @@ -0,0 +1,72 @@
[...]
> + TokenTree::Punct(p) if nested == 0 && p.as_char() == ':' => {
> + new_impl_generics.push(tt);
> + if in_generic {
> + new_impl_generics.extend(quote! { ::kernel::init::Zeroable + });

Looks like the support of '+' in `quote!` is missing ;-)

Regards,
Boqun

> + inserted = true;
> + }
> + }
> + TokenTree::Punct(p) if p.as_char() == '<' => {
> + nested += 1;
> + new_impl_generics.push(tt);
> + }
> + TokenTree::Punct(p) if p.as_char() == '>' => {
> + assert!(nested > 0);
> + nested -= 1;
> + new_impl_generics.push(tt);
> + }
> + _ => new_impl_generics.push(tt),
> + }
> + }
> + assert_eq!(nested, 0);
> + if in_generic && !inserted {
> + new_impl_generics.extend(quote! { : ::kernel::init::Zeroable });
> + }
> + quote! {
> + ::kernel::__derive_zeroable!(
> + parse_input:
> + @sig(#(#rest)*),
> + @impl_generics(#(#new_impl_generics)*),
> + @ty_generics(#(#ty_generics)*),
> + @body(#last),
> + );
> + }
> +}
> --
> 2.41.0
>
>