linux-kernel - Re: [PATCH v3] rust: macros: vtable: fix `HAS_*` redefinition (`gen_const

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20230809194802.46aa18d0.gary@garyguo.net>
Date:   Wed, 9 Aug 2023 19:48:02 +0100
From:   Gary Guo <gary@...yguo.net>
To:     "Qingsong Chen" <changxian.cqs@...group.com>
Cc:     linux-kernel@...r.kernel.org,
        "田洪亮" <tate.thl@...group.com>,
        "Miguel Ojeda" <ojeda@...nel.org>,
        "Alex Gaynor" <alex.gaynor@...il.com>,
        "Wedson Almeida Filho" <wedsonaf@...il.com>,
        "Boqun Feng" <boqun.feng@...il.com>,
        "Björn Roy Baron" <bjorn3_gh@...tonmail.com>,
        "Benno Lossin" <benno.lossin@...ton.me>,
        "Sergio González Collado" <sergio.collado@...il.com>,
        <rust-for-linux@...r.kernel.org>
Subject: Re: [PATCH v3] rust: macros: vtable: fix `HAS_*` redefinition
 (`gen_const_name`)

On Tue, 08 Aug 2023 10:54:01 +0800
"Qingsong Chen" <changxian.cqs@...group.com> wrote:

> If we define the same function name twice in a trait (using `#[cfg]`),
> the `vtable` macro will redefine its `gen_const_name`, e.g. this will
> define `HAS_BAR` twice:
> 
>     #[vtable]
>     pub trait Foo {
>         #[cfg(CONFIG_X)]
>         fn bar();
> 
>         #[cfg(not(CONFIG_X))]
>         fn bar(x: usize);
>     }
> 
> Fixes: b44becc5ee80 ("rust: macros: add `#[vtable]` proc macro")
> Signed-off-by: Qingsong Chen <changxian.cqs@...group.com>

Reviewed-by: Gary Guo <gary@...yguo.net>

> ---
> v1 -> v2:
> - Use `BTreeSet` and existing `consts` as suggested by Alice and Gary.
> - Reword commit messages as suggested by Miguel.
> v2 -> v3:
> - No need to replace `HashSet` with `BTreeSet`, since `consts` is never
>   iterated on.
> 
>  rust/macros/vtable.rs | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/rust/macros/vtable.rs b/rust/macros/vtable.rs
> index 34d5e7fb5768..ee06044fcd4f 100644
> --- a/rust/macros/vtable.rs
> +++ b/rust/macros/vtable.rs
> @@ -74,6 +74,7 @@ pub(crate) fn vtable(_attr: TokenStream, ts: TokenStream) -> TokenStream {
>                  const {gen_const_name}: bool = false;",
>              )
>              .unwrap();
> +            consts.insert(gen_const_name);
>          }
>      } else {
>          const_items = "const USE_VTABLE_ATTR: () = ();".to_owned();