rustc_attr_parsing/attributes/semantics.rs
1use rustc_attr_data_structures::AttributeKind;
2use rustc_feature::{AttributeTemplate, template};
3use rustc_span::{Symbol, sym};
4
5use crate::attributes::{AttributeOrder, OnDuplicate, SingleAttributeParser};
6use crate::context::{AcceptContext, Stage};
7use crate::parser::ArgParser;
8
9pub(crate) struct MayDangleParser;
10impl<S: Stage> SingleAttributeParser<S> for MayDangleParser {
11 const PATH: &[Symbol] = &[sym::may_dangle];
12 const ATTRIBUTE_ORDER: AttributeOrder = AttributeOrder::KeepFirst;
13 const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Warn;
14 const TEMPLATE: AttributeTemplate = template!(Word);
15
16 fn convert(cx: &mut AcceptContext<'_, '_, S>, args: &ArgParser<'_>) -> Option<AttributeKind> {
17 if let Err(span) = args.no_args() {
18 cx.expected_no_args(span);
19 }
20 Some(AttributeKind::MayDangle(cx.attr_span))
21 }
22}