rustc_attr_parsing/attributes/
codegen_attrs.rs

1use rustc_hir::attrs::{CoverageAttrKind, OptimizeAttr, RtsanSetting, SanitizerSet, UsedBy};
2use rustc_session::errors::feature_err;
3use rustc_span::edition::Edition::Edition2024;
4
5use super::prelude::*;
6use crate::attributes::AttributeSafety;
7use crate::session_diagnostics::{
8    NakedFunctionIncompatibleAttribute, NullOnExport, NullOnObjcClass, NullOnObjcSelector,
9    ObjcClassExpectedStringLiteral, ObjcSelectorExpectedStringLiteral,
10};
11use crate::target_checking::Policy::AllowSilent;
12
13pub(crate) struct OptimizeParser;
14
15impl SingleAttributeParser for OptimizeParser {
16    const PATH: &[Symbol] = &[sym::optimize];
17    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(&[
18        Allow(Target::Fn),
19        Allow(Target::Closure),
20        Allow(Target::Method(MethodKind::Trait { body: true })),
21        Allow(Target::Method(MethodKind::TraitImpl)),
22        Allow(Target::Method(MethodKind::Inherent)),
23    ]);
24    const TEMPLATE: AttributeTemplate = ::rustc_feature::AttributeTemplate {
    word: false,
    list: Some(&["size", "speed", "none"]),
    one_of: &[],
    name_value_str: None,
    docs: None,
}template!(List: &["size", "speed", "none"]);
25
26    fn convert(cx: &mut AcceptContext<'_, '_>, args: &ArgParser) -> Option<AttributeKind> {
27        let single = cx.expect_single_element_list(args, cx.attr_span)?;
28
29        let res = match single.meta_item().and_then(|i| i.path().word().map(|i| i.name)) {
30            Some(sym::size) => OptimizeAttr::Size,
31            Some(sym::speed) => OptimizeAttr::Speed,
32            Some(sym::none) => OptimizeAttr::DoNotOptimize,
33            _ => {
34                cx.adcx()
35                    .expected_specific_argument(single.span(), &[sym::size, sym::speed, sym::none]);
36                OptimizeAttr::Default
37            }
38        };
39
40        Some(AttributeKind::Optimize(res, cx.attr_span))
41    }
42}
43
44pub(crate) struct ColdParser;
45
46impl NoArgsAttributeParser for ColdParser {
47    const PATH: &[Symbol] = &[sym::cold];
48    const ON_DUPLICATE: OnDuplicate = OnDuplicate::Warn;
49    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowListWarnRest(&[
50        Allow(Target::Fn),
51        Allow(Target::Method(MethodKind::Trait { body: true })),
52        Allow(Target::Method(MethodKind::TraitImpl)),
53        Allow(Target::Method(MethodKind::Inherent)),
54        Allow(Target::ForeignFn),
55        Allow(Target::Closure),
56    ]);
57    const CREATE: fn(Span) -> AttributeKind = AttributeKind::Cold;
58}
59
60pub(crate) struct CoverageParser;
61
62impl SingleAttributeParser for CoverageParser {
63    const PATH: &[Symbol] = &[sym::coverage];
64    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(&[
65        Allow(Target::Fn),
66        Allow(Target::Closure),
67        Allow(Target::Method(MethodKind::Trait { body: true })),
68        Allow(Target::Method(MethodKind::TraitImpl)),
69        Allow(Target::Method(MethodKind::Inherent)),
70        Allow(Target::Impl { of_trait: true }),
71        Allow(Target::Impl { of_trait: false }),
72        Allow(Target::Mod),
73        Allow(Target::Crate),
74    ]);
75    const TEMPLATE: AttributeTemplate = ::rustc_feature::AttributeTemplate {
    word: false,
    list: None,
    one_of: &[sym::off, sym::on],
    name_value_str: None,
    docs: None,
}template!(OneOf: &[sym::off, sym::on]);
76
77    fn convert(cx: &mut AcceptContext<'_, '_>, args: &ArgParser) -> Option<AttributeKind> {
78        let arg = cx.expect_single_element_list(args, cx.attr_span)?;
79
80        let mut fail_incorrect_argument =
81            |span| cx.adcx().expected_specific_argument(span, &[sym::on, sym::off]);
82
83        let Some(arg) = arg.meta_item() else {
84            fail_incorrect_argument(arg.span());
85            return None;
86        };
87
88        let kind = match arg.path().word_sym() {
89            Some(sym::off) => CoverageAttrKind::Off,
90            Some(sym::on) => CoverageAttrKind::On,
91            None | Some(_) => {
92                fail_incorrect_argument(arg.span());
93                return None;
94            }
95        };
96
97        Some(AttributeKind::Coverage(cx.attr_span, kind))
98    }
99}
100
101pub(crate) struct ExportNameParser;
102
103impl SingleAttributeParser for ExportNameParser {
104    const PATH: &[rustc_span::Symbol] = &[sym::export_name];
105    const ON_DUPLICATE: OnDuplicate = OnDuplicate::WarnButFutureError;
106    const SAFETY: AttributeSafety = AttributeSafety::Unsafe { unsafe_since: Some(Edition2024) };
107    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(&[
108        Allow(Target::Static),
109        Allow(Target::Fn),
110        Allow(Target::Method(MethodKind::Inherent)),
111        Allow(Target::Method(MethodKind::Trait { body: true })),
112        Allow(Target::Method(MethodKind::TraitImpl)),
113        Warn(Target::Field),
114        Warn(Target::Arm),
115        Warn(Target::MacroDef),
116        Warn(Target::MacroCall),
117    ]);
118    const TEMPLATE: AttributeTemplate = ::rustc_feature::AttributeTemplate {
    word: false,
    list: None,
    one_of: &[],
    name_value_str: Some(&["name"]),
    docs: None,
}template!(NameValueStr: "name");
119
120    fn convert(cx: &mut AcceptContext<'_, '_>, args: &ArgParser) -> Option<AttributeKind> {
121        let nv = cx.expect_name_value(args, cx.attr_span, None)?;
122        let Some(name) = nv.value_as_str() else {
123            cx.adcx().expected_string_literal(nv.value_span, Some(nv.value_as_lit()));
124            return None;
125        };
126        if name.as_str().contains('\0') {
127            // `#[export_name = ...]` will be converted to a null-terminated string,
128            // so it may not contain any null characters.
129            cx.emit_err(NullOnExport { span: cx.attr_span });
130            return None;
131        }
132        Some(AttributeKind::ExportName { name, span: cx.attr_span })
133    }
134}
135
136pub(crate) struct RustcObjcClassParser;
137
138impl SingleAttributeParser for RustcObjcClassParser {
139    const PATH: &[rustc_span::Symbol] = &[sym::rustc_objc_class];
140    const ALLOWED_TARGETS: AllowedTargets =
141        AllowedTargets::AllowList(&[Allow(Target::ForeignStatic)]);
142    const TEMPLATE: AttributeTemplate = ::rustc_feature::AttributeTemplate {
    word: false,
    list: None,
    one_of: &[],
    name_value_str: Some(&["ClassName"]),
    docs: None,
}template!(NameValueStr: "ClassName");
143
144    fn convert(cx: &mut AcceptContext<'_, '_>, args: &ArgParser) -> Option<AttributeKind> {
145        let nv = cx.expect_name_value(args, cx.attr_span, None)?;
146        let Some(classname) = nv.value_as_str() else {
147            // `#[rustc_objc_class = ...]` is expected to be used as an implementation detail
148            // inside a standard library macro, but `cx.expected_string_literal` exposes too much.
149            // Use a custom error message instead.
150            cx.emit_err(ObjcClassExpectedStringLiteral { span: nv.value_span });
151            return None;
152        };
153        if classname.as_str().contains('\0') {
154            // `#[rustc_objc_class = ...]` will be converted to a null-terminated string,
155            // so it may not contain any null characters.
156            cx.emit_err(NullOnObjcClass { span: nv.value_span });
157            return None;
158        }
159        Some(AttributeKind::RustcObjcClass { classname, span: cx.attr_span })
160    }
161}
162
163pub(crate) struct RustcObjcSelectorParser;
164
165impl SingleAttributeParser for RustcObjcSelectorParser {
166    const PATH: &[rustc_span::Symbol] = &[sym::rustc_objc_selector];
167    const ALLOWED_TARGETS: AllowedTargets =
168        AllowedTargets::AllowList(&[Allow(Target::ForeignStatic)]);
169    const TEMPLATE: AttributeTemplate = ::rustc_feature::AttributeTemplate {
    word: false,
    list: None,
    one_of: &[],
    name_value_str: Some(&["methodName"]),
    docs: None,
}template!(NameValueStr: "methodName");
170
171    fn convert(cx: &mut AcceptContext<'_, '_>, args: &ArgParser) -> Option<AttributeKind> {
172        let nv = cx.expect_name_value(args, cx.attr_span, None)?;
173        let Some(methname) = nv.value_as_str() else {
174            // `#[rustc_objc_selector = ...]` is expected to be used as an implementation detail
175            // inside a standard library macro, but `cx.expected_string_literal` exposes too much.
176            // Use a custom error message instead.
177            cx.emit_err(ObjcSelectorExpectedStringLiteral { span: nv.value_span });
178            return None;
179        };
180        if methname.as_str().contains('\0') {
181            // `#[rustc_objc_selector = ...]` will be converted to a null-terminated string,
182            // so it may not contain any null characters.
183            cx.emit_err(NullOnObjcSelector { span: nv.value_span });
184            return None;
185        }
186        Some(AttributeKind::RustcObjcSelector { methname, span: cx.attr_span })
187    }
188}
189
190#[derive(#[automatically_derived]
impl ::core::default::Default for NakedParser {
    #[inline]
    fn default() -> NakedParser {
        NakedParser { span: ::core::default::Default::default() }
    }
}Default)]
191pub(crate) struct NakedParser {
192    span: Option<Span>,
193}
194
195impl AttributeParser for NakedParser {
196    const ATTRIBUTES: AcceptMapping<Self> =
197        &[(&[sym::naked], ::rustc_feature::AttributeTemplate {
    word: true,
    list: None,
    one_of: &[],
    name_value_str: None,
    docs: None,
}template!(Word), |this, cx, args| {
198            let Some(()) = cx.expect_no_args(args) else {
199                return;
200            };
201
202            if let Some(earlier) = this.span {
203                let span = cx.attr_span;
204                cx.warn_unused_duplicate(earlier, span);
205            } else {
206                this.span = Some(cx.attr_span);
207            }
208        })];
209    const SAFETY: AttributeSafety = AttributeSafety::Unsafe { unsafe_since: None };
210    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(&[
211        Allow(Target::Fn),
212        Allow(Target::Method(MethodKind::Inherent)),
213        Allow(Target::Method(MethodKind::Trait { body: true })),
214        Allow(Target::Method(MethodKind::TraitImpl)),
215        Warn(Target::MacroCall),
216    ]);
217
218    fn finalize(self, cx: &FinalizeContext<'_, '_>) -> Option<AttributeKind> {
219        // FIXME(jdonszelmann): upgrade this list to *parsed* attributes
220        // once all of these have parsed forms. That'd make the check much nicer...
221        //
222        // many attributes don't make sense in combination with #[naked].
223        // Notable attributes that are incompatible with `#[naked]` are:
224        //
225        // * `#[inline]`
226        // * `#[track_caller]`
227        // * `#[test]`, `#[ignore]`, `#[should_panic]`
228        //
229        // NOTE: when making changes to this list, check that `error_codes/E0736.md` remains
230        // accurate.
231        const ALLOW_LIST: &[rustc_span::Symbol] = &[
232            // conditional compilation
233            sym::cfg_trace,
234            sym::cfg_attr_trace,
235            // testing (allowed here so better errors can be generated in `rustc_builtin_macros::test`)
236            sym::test,
237            sym::ignore,
238            sym::should_panic,
239            sym::bench,
240            // diagnostics
241            sym::allow,
242            sym::warn,
243            sym::deny,
244            sym::forbid,
245            sym::deprecated,
246            sym::must_use,
247            // abi, linking and FFI
248            sym::cold,
249            sym::export_name,
250            sym::link_section,
251            sym::linkage,
252            sym::no_mangle,
253            sym::instruction_set,
254            sym::repr,
255            sym::rustc_std_internal_symbol,
256            // FIXME(#82232, #143834): temporarily renamed to mitigate `#[align]` nameres ambiguity
257            sym::rustc_align,
258            sym::rustc_align_static,
259            // obviously compatible with self
260            sym::naked,
261            // documentation
262            sym::doc,
263        ];
264
265        let span = self.span?;
266
267        // only if we found a naked attribute do we do the somewhat expensive check
268        'outer: for other_attr in cx.all_attrs {
269            for allowed_attr in ALLOW_LIST {
270                if other_attr.segments().next().is_some_and(|i| cx.tools.contains(&i.name)) {
271                    // effectively skips the error message  being emitted below
272                    // if it's a tool attribute
273                    continue 'outer;
274                }
275                if other_attr.word_is(*allowed_attr) {
276                    // effectively skips the error message  being emitted below
277                    // if its an allowed attribute
278                    continue 'outer;
279                }
280
281                if other_attr.word_is(sym::target_feature) {
282                    if !cx.features().naked_functions_target_feature() {
283                        feature_err(
284                            &cx.sess(),
285                            sym::naked_functions_target_feature,
286                            other_attr.span(),
287                            "`#[target_feature(/* ... */)]` is currently unstable on `#[naked]` functions",
288                        ).emit();
289                    }
290
291                    continue 'outer;
292                }
293            }
294
295            cx.emit_err(NakedFunctionIncompatibleAttribute {
296                span: other_attr.span(),
297                naked_span: span,
298                attr: other_attr.get_attribute_path().to_string(),
299            });
300        }
301
302        Some(AttributeKind::Naked(span))
303    }
304}
305
306pub(crate) struct TrackCallerParser;
307impl NoArgsAttributeParser for TrackCallerParser {
308    const PATH: &[Symbol] = &[sym::track_caller];
309    const ON_DUPLICATE: OnDuplicate = OnDuplicate::Warn;
310    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(&[
311        Allow(Target::Fn),
312        Allow(Target::Method(MethodKind::Inherent)),
313        Allow(Target::Method(MethodKind::Trait { body: true })),
314        Allow(Target::Method(MethodKind::TraitImpl)),
315        Allow(Target::Method(MethodKind::Trait { body: false })), // `#[track_caller]` is inherited from trait methods
316        Allow(Target::ForeignFn),
317        Allow(Target::Closure),
318        Warn(Target::MacroDef),
319        Warn(Target::Arm),
320        Warn(Target::Field),
321        Warn(Target::MacroCall),
322    ]);
323    const CREATE: fn(Span) -> AttributeKind = AttributeKind::TrackCaller;
324}
325
326pub(crate) struct NoMangleParser;
327impl NoArgsAttributeParser for NoMangleParser {
328    const PATH: &[Symbol] = &[sym::no_mangle];
329    const ON_DUPLICATE: OnDuplicate = OnDuplicate::Warn;
330    const SAFETY: AttributeSafety = AttributeSafety::Unsafe { unsafe_since: Some(Edition2024) };
331    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowListWarnRest(&[
332        Allow(Target::Fn),
333        Allow(Target::Static),
334        Allow(Target::Method(MethodKind::Inherent)),
335        Allow(Target::Method(MethodKind::TraitImpl)),
336        AllowSilent(Target::Const), // Handled in the `InvalidNoMangleItems` pass
337        Error(Target::Closure),
338    ]);
339    const CREATE: fn(Span) -> AttributeKind = AttributeKind::NoMangle;
340}
341
342#[derive(#[automatically_derived]
impl ::core::default::Default for UsedParser {
    #[inline]
    fn default() -> UsedParser {
        UsedParser {
            first_compiler: ::core::default::Default::default(),
            first_linker: ::core::default::Default::default(),
            first_default: ::core::default::Default::default(),
        }
    }
}Default)]
343pub(crate) struct UsedParser {
344    first_compiler: Option<Span>,
345    first_linker: Option<Span>,
346    first_default: Option<Span>,
347}
348
349// A custom `AttributeParser` is used rather than a Simple attribute parser because
350// - Specifying two `#[used]` attributes is a warning (but will be an error in the future)
351// - But specifying two conflicting attributes: `#[used(compiler)]` and `#[used(linker)]` is already an error today
352// We can change this to a Simple parser once the warning becomes an error
353impl AttributeParser for UsedParser {
354    const ATTRIBUTES: AcceptMapping<Self> = &[(
355        &[sym::used],
356        ::rustc_feature::AttributeTemplate {
    word: true,
    list: Some(&["compiler", "linker"]),
    one_of: &[],
    name_value_str: None,
    docs: None,
}template!(Word, List: &["compiler", "linker"]),
357        |group: &mut Self, cx, args| {
358            let used_by = match args {
359                ArgParser::NoArgs => UsedBy::Default,
360                ArgParser::List(list) => {
361                    let Some(l) = cx.expect_single(list) else {
362                        return;
363                    };
364
365                    match l.meta_item().and_then(|i| i.path().word_sym()) {
366                        Some(sym::compiler) => {
367                            if !cx.features().used_with_arg() {
368                                feature_err(
369                                    &cx.sess(),
370                                    sym::used_with_arg,
371                                    cx.attr_span,
372                                    "`#[used(compiler)]` is currently unstable",
373                                )
374                                .emit();
375                            }
376                            UsedBy::Compiler
377                        }
378                        Some(sym::linker) => {
379                            if !cx.features().used_with_arg() {
380                                feature_err(
381                                    &cx.sess(),
382                                    sym::used_with_arg,
383                                    cx.attr_span,
384                                    "`#[used(linker)]` is currently unstable",
385                                )
386                                .emit();
387                            }
388                            UsedBy::Linker
389                        }
390                        _ => {
391                            cx.adcx().expected_specific_argument(
392                                l.span(),
393                                &[sym::compiler, sym::linker],
394                            );
395                            return;
396                        }
397                    }
398                }
399                ArgParser::NameValue(_) => return,
400            };
401
402            let attr_span = cx.attr_span;
403
404            // `#[used]` is interpreted as `#[used(linker)]` (though depending on target OS the
405            // circumstances are more complicated). While we're checking `used_by`, also report
406            // these cross-`UsedBy` duplicates to warn.
407            let target = match used_by {
408                UsedBy::Compiler => &mut group.first_compiler,
409                UsedBy::Linker => {
410                    if let Some(prev) = group.first_default {
411                        cx.warn_unused_duplicate(prev, attr_span);
412                        return;
413                    }
414                    &mut group.first_linker
415                }
416                UsedBy::Default => {
417                    if let Some(prev) = group.first_linker {
418                        cx.warn_unused_duplicate(prev, attr_span);
419                        return;
420                    }
421                    &mut group.first_default
422                }
423            };
424
425            if let Some(prev) = *target {
426                cx.warn_unused_duplicate(prev, attr_span);
427            } else {
428                *target = Some(attr_span);
429            }
430        },
431    )];
432    const ALLOWED_TARGETS: AllowedTargets =
433        AllowedTargets::AllowList(&[Allow(Target::Static), Warn(Target::MacroCall)]);
434
435    fn finalize(self, _cx: &FinalizeContext<'_, '_>) -> Option<AttributeKind> {
436        // If a specific form of `used` is specified, it takes precedence over generic `#[used]`.
437        // If both `linker` and `compiler` are specified, use `linker`.
438        Some(match (self.first_compiler, self.first_linker, self.first_default) {
439            (_, Some(span), _) => AttributeKind::Used { used_by: UsedBy::Linker, span },
440            (Some(span), _, _) => AttributeKind::Used { used_by: UsedBy::Compiler, span },
441            (_, _, Some(span)) => AttributeKind::Used { used_by: UsedBy::Default, span },
442            (None, None, None) => return None,
443        })
444    }
445}
446
447fn parse_tf_attribute(
448    cx: &mut AcceptContext<'_, '_>,
449    args: &ArgParser,
450) -> impl IntoIterator<Item = (Symbol, Span)> {
451    let mut features = Vec::new();
452    let Some(list) = cx.expect_list(args, cx.attr_span) else {
453        return features;
454    };
455    if list.is_empty() {
456        let attr_span = cx.attr_span;
457        cx.adcx().warn_empty_attribute(attr_span);
458        return features;
459    }
460    for item in list.mixed() {
461        let Some((ident, value)) = cx.expect_name_value(item, item.span(), Some(sym::enable))
462        else {
463            return features;
464        };
465
466        // Validate name
467        if ident.name != sym::enable {
468            cx.adcx().expected_specific_argument(ident.span, &[sym::enable]);
469            return features;
470        }
471
472        // Use value
473        let Some(value_str) = value.value_as_str() else {
474            cx.adcx().expected_string_literal(value.value_span, Some(value.value_as_lit()));
475            return features;
476        };
477        for feature in value_str.as_str().split(",") {
478            features.push((Symbol::intern(feature), item.span()));
479        }
480    }
481    features
482}
483
484pub(crate) struct TargetFeatureParser;
485
486impl CombineAttributeParser for TargetFeatureParser {
487    type Item = (Symbol, Span);
488    const PATH: &[Symbol] = &[sym::target_feature];
489    const CONVERT: ConvertFn<Self::Item> = |items, span| AttributeKind::TargetFeature {
490        features: items,
491        attr_span: span,
492        was_forced: false,
493    };
494    const TEMPLATE: AttributeTemplate = ::rustc_feature::AttributeTemplate {
    word: false,
    list: Some(&["enable = \"feat1, feat2\""]),
    one_of: &[],
    name_value_str: None,
    docs: None,
}template!(List: &["enable = \"feat1, feat2\""]);
495
496    fn extend(
497        cx: &mut AcceptContext<'_, '_>,
498        args: &ArgParser,
499    ) -> impl IntoIterator<Item = Self::Item> {
500        parse_tf_attribute(cx, args)
501    }
502
503    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(&[
504        Allow(Target::Fn),
505        Allow(Target::Method(MethodKind::Inherent)),
506        Allow(Target::Method(MethodKind::Trait { body: true })),
507        Allow(Target::Method(MethodKind::TraitImpl)),
508        Warn(Target::Statement),
509        Warn(Target::Field),
510        Warn(Target::Arm),
511        Warn(Target::MacroDef),
512        Warn(Target::MacroCall),
513    ]);
514}
515
516pub(crate) struct ForceTargetFeatureParser;
517
518impl CombineAttributeParser for ForceTargetFeatureParser {
519    type Item = (Symbol, Span);
520    const PATH: &[Symbol] = &[sym::force_target_feature];
521    const SAFETY: AttributeSafety = AttributeSafety::Unsafe { unsafe_since: None };
522    const CONVERT: ConvertFn<Self::Item> = |items, span| AttributeKind::TargetFeature {
523        features: items,
524        attr_span: span,
525        was_forced: true,
526    };
527    const TEMPLATE: AttributeTemplate = ::rustc_feature::AttributeTemplate {
    word: false,
    list: Some(&["enable = \"feat1, feat2\""]),
    one_of: &[],
    name_value_str: None,
    docs: None,
}template!(List: &["enable = \"feat1, feat2\""]);
528    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(&[
529        Allow(Target::Fn),
530        Allow(Target::Method(MethodKind::Inherent)),
531        Allow(Target::Method(MethodKind::Trait { body: true })),
532        Allow(Target::Method(MethodKind::TraitImpl)),
533    ]);
534
535    fn extend(
536        cx: &mut AcceptContext<'_, '_>,
537        args: &ArgParser,
538    ) -> impl IntoIterator<Item = Self::Item> {
539        parse_tf_attribute(cx, args)
540    }
541}
542
543pub(crate) struct SanitizeParser;
544
545impl SingleAttributeParser for SanitizeParser {
546    const PATH: &[Symbol] = &[sym::sanitize];
547
548    // FIXME: still checked in check_attrs.rs
549    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(ALL_TARGETS);
550
551    const TEMPLATE: AttributeTemplate = ::rustc_feature::AttributeTemplate {
    word: false,
    list: Some(&[r#"address = "on|off""#, r#"kernel_address = "on|off""#,
                    r#"cfi = "on|off""#, r#"hwaddress = "on|off""#,
                    r#"kernel_hwaddress = "on|off""#, r#"kcfi = "on|off""#,
                    r#"memory = "on|off""#, r#"memtag = "on|off""#,
                    r#"shadow_call_stack = "on|off""#, r#"thread = "on|off""#,
                    r#"realtime = "nonblocking|blocking|caller""#]),
    one_of: &[],
    name_value_str: None,
    docs: None,
}template!(List: &[
552        r#"address = "on|off""#,
553        r#"kernel_address = "on|off""#,
554        r#"cfi = "on|off""#,
555        r#"hwaddress = "on|off""#,
556        r#"kernel_hwaddress = "on|off""#,
557        r#"kcfi = "on|off""#,
558        r#"memory = "on|off""#,
559        r#"memtag = "on|off""#,
560        r#"shadow_call_stack = "on|off""#,
561        r#"thread = "on|off""#,
562        r#"realtime = "nonblocking|blocking|caller""#,
563    ]);
564
565    fn convert(cx: &mut AcceptContext<'_, '_>, args: &ArgParser) -> Option<AttributeKind> {
566        let list = cx.expect_list(args, cx.attr_span)?;
567
568        let mut on_set = SanitizerSet::empty();
569        let mut off_set = SanitizerSet::empty();
570        let mut rtsan = None;
571
572        for item in list.mixed() {
573            let Some((ident, value)) = cx.expect_name_value(item, item.span(), None) else {
574                continue;
575            };
576
577            let mut apply = |s: SanitizerSet| {
578                let is_on = match value.value_as_str() {
579                    Some(sym::on) => true,
580                    Some(sym::off) => false,
581                    Some(_) => {
582                        cx.adcx().expected_specific_argument_strings(
583                            value.value_span,
584                            &[sym::on, sym::off],
585                        );
586                        return;
587                    }
588                    None => {
589                        cx.adcx()
590                            .expected_string_literal(value.value_span, Some(value.value_as_lit()));
591                        return;
592                    }
593                };
594
595                if is_on {
596                    on_set |= s;
597                } else {
598                    off_set |= s;
599                }
600            };
601
602            match ident.name {
603                sym::address | sym::kernel_address => {
604                    apply(SanitizerSet::ADDRESS | SanitizerSet::KERNELADDRESS)
605                }
606                sym::cfi => apply(SanitizerSet::CFI),
607                sym::kcfi => apply(SanitizerSet::KCFI),
608                sym::memory => apply(SanitizerSet::MEMORY),
609                sym::memtag => apply(SanitizerSet::MEMTAG),
610                sym::shadow_call_stack => apply(SanitizerSet::SHADOWCALLSTACK),
611                sym::thread => apply(SanitizerSet::THREAD),
612                sym::hwaddress | sym::kernel_hwaddress => {
613                    apply(SanitizerSet::HWADDRESS | SanitizerSet::KERNELHWADDRESS)
614                }
615                sym::realtime => match value.value_as_str() {
616                    Some(sym::nonblocking) => rtsan = Some(RtsanSetting::Nonblocking),
617                    Some(sym::blocking) => rtsan = Some(RtsanSetting::Blocking),
618                    Some(sym::caller) => rtsan = Some(RtsanSetting::Caller),
619                    _ => {
620                        cx.adcx().expected_specific_argument_strings(
621                            value.value_span,
622                            &[sym::nonblocking, sym::blocking, sym::caller],
623                        );
624                    }
625                },
626                _ => {
627                    cx.adcx().expected_specific_argument_strings(
628                        ident.span,
629                        &[
630                            sym::address,
631                            sym::kernel_address,
632                            sym::cfi,
633                            sym::kcfi,
634                            sym::memory,
635                            sym::memtag,
636                            sym::shadow_call_stack,
637                            sym::thread,
638                            sym::hwaddress,
639                            sym::kernel_hwaddress,
640                            sym::realtime,
641                        ],
642                    );
643                    continue;
644                }
645            }
646        }
647
648        Some(AttributeKind::Sanitize { on_set, off_set, rtsan, span: cx.attr_span })
649    }
650}
651
652pub(crate) struct ThreadLocalParser;
653
654impl NoArgsAttributeParser for ThreadLocalParser {
655    const PATH: &[Symbol] = &[sym::thread_local];
656    const ALLOWED_TARGETS: AllowedTargets =
657        AllowedTargets::AllowList(&[Allow(Target::Static), Allow(Target::ForeignStatic)]);
658    const CREATE: fn(Span) -> AttributeKind = |_| AttributeKind::ThreadLocal;
659}
660
661pub(crate) struct RustcPassIndirectlyInNonRusticAbisParser;
662
663impl NoArgsAttributeParser for RustcPassIndirectlyInNonRusticAbisParser {
664    const PATH: &[Symbol] = &[sym::rustc_pass_indirectly_in_non_rustic_abis];
665    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(&[Allow(Target::Struct)]);
666    const CREATE: fn(Span) -> AttributeKind = AttributeKind::RustcPassIndirectlyInNonRusticAbis;
667}
668
669pub(crate) struct RustcEiiForeignItemParser;
670
671impl NoArgsAttributeParser for RustcEiiForeignItemParser {
672    const PATH: &[Symbol] = &[sym::rustc_eii_foreign_item];
673    const ALLOWED_TARGETS: AllowedTargets =
674        AllowedTargets::AllowList(&[Allow(Target::ForeignFn), Allow(Target::ForeignStatic)]);
675    const CREATE: fn(Span) -> AttributeKind = |_| AttributeKind::RustcEiiForeignItem;
676}
677
678pub(crate) struct PatchableFunctionEntryParser;
679
680impl SingleAttributeParser for PatchableFunctionEntryParser {
681    const PATH: &[Symbol] = &[sym::patchable_function_entry];
682    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(&[Allow(Target::Fn)]);
683    const TEMPLATE: AttributeTemplate = ::rustc_feature::AttributeTemplate {
    word: false,
    list: Some(&["prefix_nops = m, entry_nops = n"]),
    one_of: &[],
    name_value_str: None,
    docs: None,
}template!(List: &["prefix_nops = m, entry_nops = n"]);
684
685    fn convert(cx: &mut AcceptContext<'_, '_>, args: &ArgParser) -> Option<AttributeKind> {
686        let meta_item_list = cx.expect_list(args, cx.attr_span)?;
687
688        let mut prefix = None;
689        let mut entry = None;
690
691        if meta_item_list.len() == 0 {
692            cx.adcx().expected_at_least_one_argument(meta_item_list.span);
693            return None;
694        }
695
696        let mut errored = false;
697
698        for item in meta_item_list.mixed() {
699            let Some((ident, value)) = cx.expect_name_value(item, item.span(), None) else {
700                continue;
701            };
702
703            let attrib_to_write = match ident.name {
704                sym::prefix_nops => {
705                    // Duplicate prefixes are not allowed
706                    if prefix.is_some() {
707                        errored = true;
708                        cx.adcx().duplicate_key(ident.span, sym::prefix_nops);
709                        continue;
710                    }
711                    &mut prefix
712                }
713                sym::entry_nops => {
714                    // Duplicate entries are not allowed
715                    if entry.is_some() {
716                        errored = true;
717                        cx.adcx().duplicate_key(ident.span, sym::entry_nops);
718                        continue;
719                    }
720                    &mut entry
721                }
722                _ => {
723                    errored = true;
724                    cx.adcx().expected_specific_argument(
725                        ident.span,
726                        &[sym::prefix_nops, sym::entry_nops],
727                    );
728                    continue;
729                }
730            };
731
732            let rustc_ast::LitKind::Int(val, _) = value.value_as_lit().kind else {
733                errored = true;
734                cx.adcx().expected_integer_literal(value.value_span);
735                continue;
736            };
737
738            let Ok(val) = val.get().try_into() else {
739                errored = true;
740                cx.adcx().expected_integer_literal_in_range(
741                    value.value_span,
742                    u8::MIN as isize,
743                    u8::MAX as isize,
744                );
745                continue;
746            };
747
748            *attrib_to_write = Some(val);
749        }
750
751        if errored {
752            None
753        } else {
754            Some(AttributeKind::PatchableFunctionEntry {
755                prefix: prefix.unwrap_or(0),
756                entry: entry.unwrap_or(0),
757            })
758        }
759    }
760}
rustc_attr_parsing/attributes/codegen_attrs.rs

rustc_attr_parsing/attributes/
codegen_attrs.rs
