[PATCH v2] rust: macros: vtable: fix `HAS_*` redefinition (`gen_const_name`)
From: Qingsong Chen <hidden>
Date: 2023-08-03 14:11:57
Also in:
lkml
Subsystem:
rust, the rest · Maintainers:
Miguel Ojeda, Linus Torvalds
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);
}
Changelog:
----------
v1 -> v2:
- Use `BTreeSet` and existing `consts` as suggested by Alice and Gary.
- Reword commit messages as suggested by Miguel.
====================
Fixes: b44becc5ee80 ("rust: macros: add `#[vtable]` proc macro")
Signed-off-by: Qingsong Chen <redacted>
---
rust/macros/vtable.rs | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/rust/macros/vtable.rs b/rust/macros/vtable.rs
index 34d5e7fb5768..8a1baedcc280 100644
--- a/rust/macros/vtable.rs
+++ b/rust/macros/vtable.rs@@ -1,7 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 use proc_macro::{Delimiter, Group, TokenStream, TokenTree}; -use std::collections::HashSet; +use std::collections::BTreeSet; use std::fmt::Write; pub(crate) fn vtable(_attr: TokenStream, ts: TokenStream) -> TokenStream {
@@ -28,7 +28,7 @@ pub(crate) fn vtable(_attr: TokenStream, ts: TokenStream) -> TokenStream { let mut body_it = body.stream().into_iter(); let mut functions = Vec::new(); - let mut consts = HashSet::new(); + let mut consts = BTreeSet::new(); while let Some(token) = body_it.next() { match token { TokenTree::Ident(ident) if ident.to_string() == "fn" => {
@@ -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();
--
2.40.1