hir_expand/
inert_attr_macro.rs

1//! Builtin attributes resolved by nameres.
2//!
3//! The actual definitions were copied from rustc's `compiler/rustc_feature/src/builtin_attrs.rs`.
4//!
5//! It was last synchronized with upstream commit c3def263a44e07e09ae6d57abfc8650227fb4972.
6//!
7//! The macros were adjusted to only expand to the attribute name, since that is all we need to do
8//! name resolution, and `BUILTIN_ATTRIBUTES` is almost entirely unchanged from the original, to
9//! ease updating.
10
11use std::sync::OnceLock;
12
13use intern::Symbol;
14use rustc_hash::FxHashMap;
15
16pub struct BuiltinAttribute {
17    pub name: &'static str,
18    pub template: AttributeTemplate,
19}
20
21/// A template that the attribute input must match.
22/// Only top-level shape (`#[attr]` vs `#[attr(...)]` vs `#[attr = ...]`) is considered now.
23#[derive(Clone, Copy)]
24pub struct AttributeTemplate {
25    pub word: bool,
26    pub list: Option<&'static str>,
27    pub name_value_str: Option<&'static str>,
28}
29
30pub fn find_builtin_attr_idx(name: &Symbol) -> Option<usize> {
31    static BUILTIN_LOOKUP_TABLE: OnceLock<FxHashMap<Symbol, usize>> = OnceLock::new();
32    BUILTIN_LOOKUP_TABLE
33        .get_or_init(|| {
34            INERT_ATTRIBUTES
35                .iter()
36                .map(|attr| attr.name)
37                .enumerate()
38                .map(|(a, b)| (Symbol::intern(b), a))
39                .collect()
40        })
41        .get(name)
42        .copied()
43}
44
45/// A convenience macro for constructing attribute templates.
46/// E.g., `template!(Word, List: "description")` means that the attribute
47/// supports forms `#[attr]` and `#[attr(description)]`.
48macro_rules! template {
49    (Word) => { template!(@ true, None, None) };
50    (List: $descr: expr) => { template!(@ false, Some($descr), None) };
51    (NameValueStr: $descr: expr) => { template!(@ false, None, Some($descr)) };
52    (Word, List: $descr: expr) => { template!(@ true, Some($descr), None) };
53    (Word, NameValueStr: $descr: expr) => { template!(@ true, None, Some($descr)) };
54    (List: $descr1: expr, NameValueStr: $descr2: expr) => {
55        template!(@ false, Some($descr1), Some($descr2))
56    };
57    (Word, List: $descr1: expr, NameValueStr: $descr2: expr) => {
58        template!(@ true, Some($descr1), Some($descr2))
59    };
60    (@ $word: expr, $list: expr, $name_value_str: expr) => {
61        AttributeTemplate {
62            word: $word, list: $list, name_value_str: $name_value_str
63        }
64    };
65}
66
67macro_rules! ungated {
68    ($attr:ident, $typ:expr, $tpl:expr, $duplicates:expr $(, @only_local: $only_local:expr)? $(,)?) => {
69        BuiltinAttribute { name: stringify!($attr), template: $tpl }
70    };
71}
72
73macro_rules! gated {
74    ($attr:ident, $typ:expr, $tpl:expr, $duplicates:expr $(, @only_local: $only_local:expr)?, $gate:ident, $msg:expr $(,)?) => {
75        BuiltinAttribute { name: stringify!($attr), template: $tpl }
76    };
77    ($attr:ident, $typ:expr, $tpl:expr, $duplicates:expr $(, @only_local: $only_local:expr)?, $msg:expr $(,)?) => {
78        BuiltinAttribute { name: stringify!($attr), template: $tpl }
79    };
80}
81
82macro_rules! rustc_attr {
83    (TEST, $attr:ident, $typ:expr, $tpl:expr, $duplicate:expr $(, @only_local: $only_local:expr)? $(,)?) => {
84        rustc_attr!(
85            $attr,
86            $typ,
87            $tpl,
88            $duplicate,
89            $(@only_local: $only_local,)?
90            concat!(
91                "the `#[",
92                stringify!($attr),
93                "]` attribute is just used for rustc unit tests \
94                and will never be stable",
95            ),
96        )
97    };
98    ($attr:ident, $typ:expr, $tpl:expr, $duplicates:expr $(, @only_local: $only_local:expr)?, $msg:expr $(,)?) => {
99        BuiltinAttribute { name: stringify!($attr), template: $tpl }
100    };
101}
102
103#[allow(unused_macros)]
104macro_rules! experimental {
105    ($attr:ident) => {
106        concat!("the `#[", stringify!($attr), "]` attribute is an experimental feature")
107    };
108}
109
110/// Attributes that have a special meaning to rustc or rustdoc.
111#[rustfmt::skip]
112pub const INERT_ATTRIBUTES: &[BuiltinAttribute] = &[
113    // ==========================================================================
114    // Stable attributes:
115    // ==========================================================================
116
117    // Conditional compilation:
118    ungated!(cfg, Normal, template!(List: "predicate"), DuplicatesOk),
119    ungated!(cfg_attr, Normal, template!(List: "predicate, attr1, attr2, ..."), DuplicatesOk),
120
121    // Testing:
122    ungated!(ignore, Normal, template!(Word, NameValueStr: "reason"), WarnFollowing),
123    ungated!(
124        should_panic, Normal,
125        template!(Word, List: r#"expected = "reason""#, NameValueStr: "reason"), FutureWarnFollowing,
126    ),
127
128    // Macros:
129    ungated!(automatically_derived, Normal, template!(Word), WarnFollowing),
130    ungated!(macro_use, Normal, template!(Word, List: "name1, name2, ..."), WarnFollowingWordOnly),
131    ungated!(macro_escape, Normal, template!(Word), WarnFollowing), // Deprecated synonym for `macro_use`.
132    ungated!(macro_export, Normal, template!(Word, List: "local_inner_macros"), WarnFollowing),
133    ungated!(proc_macro, Normal, template!(Word), ErrorFollowing),
134    ungated!(
135        proc_macro_derive, Normal,
136        template!(List: "TraitName, /*opt*/ attributes(name1, name2, ...)"), ErrorFollowing,
137    ),
138    ungated!(proc_macro_attribute, Normal, template!(Word), ErrorFollowing),
139
140    // Lints:
141    ungated!(
142        warn, Normal, template!(List: r#"lint1, lint2, ..., /*opt*/ reason = "...""#),
143        DuplicatesOk, @only_local: true,
144    ),
145    ungated!(
146        allow, Normal, template!(List: r#"lint1, lint2, ..., /*opt*/ reason = "...""#),
147        DuplicatesOk, @only_local: true,
148    ),
149    ungated!(
150        expect, Normal, template!(List: r#"lint1, lint2, ..., /*opt*/ reason = "...""#),
151        DuplicatesOk, @only_local: true,
152    ),
153    ungated!(
154        forbid, Normal, template!(List: r#"lint1, lint2, ..., /*opt*/ reason = "...""#),
155        DuplicatesOk, @only_local: true,
156    ),
157    ungated!(
158        deny, Normal, template!(List: r#"lint1, lint2, ..., /*opt*/ reason = "...""#),
159        DuplicatesOk, @only_local: true,
160    ),
161    ungated!(must_use, Normal, template!(Word, NameValueStr: "reason"), FutureWarnFollowing),
162    gated!(
163        must_not_suspend, Normal, template!(Word, NameValueStr: "reason"), WarnFollowing,
164        experimental!(must_not_suspend)
165    ),
166    ungated!(
167        deprecated, Normal,
168        template!(
169            Word,
170            List: r#"/*opt*/ since = "version", /*opt*/ note = "reason""#,
171            NameValueStr: "reason"
172        ),
173        ErrorFollowing
174    ),
175
176    // Crate properties:
177    ungated!(crate_name, CrateLevel, template!(NameValueStr: "name"), FutureWarnFollowing),
178    ungated!(crate_type, CrateLevel, template!(NameValueStr: "bin|lib|..."), DuplicatesOk),
179    // crate_id is deprecated
180    ungated!(crate_id, CrateLevel, template!(NameValueStr: "ignored"), FutureWarnFollowing),
181
182    // ABI, linking, symbols, and FFI
183    ungated!(
184        link, Normal,
185        template!(List: r#"name = "...", /*opt*/ kind = "dylib|static|...", /*opt*/ wasm_import_module = "...", /*opt*/ import_name_type = "decorated|noprefix|undecorated""#),
186        DuplicatesOk,
187    ),
188    ungated!(link_name, Normal, template!(NameValueStr: "name"), FutureWarnPreceding),
189    ungated!(no_link, Normal, template!(Word), WarnFollowing),
190    ungated!(repr, Normal, template!(List: "C"), DuplicatesOk, @only_local: true),
191    ungated!(export_name, Normal, template!(NameValueStr: "name"), FutureWarnPreceding),
192    ungated!(link_section, Normal, template!(NameValueStr: "name"), FutureWarnPreceding),
193    ungated!(no_mangle, Normal, template!(Word), WarnFollowing, @only_local: true),
194    ungated!(used, Normal, template!(Word, List: "compiler|linker"), WarnFollowing, @only_local: true),
195    ungated!(link_ordinal, Normal, template!(List: "ordinal"), ErrorPreceding),
196
197    // Limits:
198    ungated!(recursion_limit, CrateLevel, template!(NameValueStr: "N"), FutureWarnFollowing),
199    ungated!(type_length_limit, CrateLevel, template!(NameValueStr: "N"), FutureWarnFollowing),
200    gated!(
201        move_size_limit, CrateLevel, template!(NameValueStr: "N"), ErrorFollowing,
202        large_assignments, experimental!(move_size_limit)
203    ),
204
205    // Entry point:
206    ungated!(start, Normal, template!(Word), WarnFollowing),
207    ungated!(no_start, CrateLevel, template!(Word), WarnFollowing),
208    ungated!(no_main, CrateLevel, template!(Word), WarnFollowing),
209
210    // Modules, prelude, and resolution:
211    ungated!(path, Normal, template!(NameValueStr: "file"), FutureWarnFollowing),
212    ungated!(no_std, CrateLevel, template!(Word), WarnFollowing),
213    ungated!(no_implicit_prelude, Normal, template!(Word), WarnFollowing),
214    ungated!(non_exhaustive, Normal, template!(Word), WarnFollowing),
215
216    // Runtime
217    ungated!(
218        windows_subsystem, CrateLevel,
219        template!(NameValueStr: "windows|console"), FutureWarnFollowing
220    ),
221    ungated!(panic_handler, Normal, template!(Word), WarnFollowing), // RFC 2070
222
223    // Code generation:
224    ungated!(inline, Normal, template!(Word, List: "always|never"), FutureWarnFollowing, @only_local: true),
225    ungated!(cold, Normal, template!(Word), WarnFollowing, @only_local: true),
226    ungated!(no_builtins, CrateLevel, template!(Word), WarnFollowing),
227    ungated!(
228        target_feature, Normal, template!(List: r#"enable = "name""#),
229        DuplicatesOk, @only_local: true,
230    ),
231    ungated!(track_caller, Normal, template!(Word), WarnFollowing),
232    ungated!(instruction_set, Normal, template!(List: "set"), ErrorPreceding),
233    gated!(
234        no_sanitize, Normal,
235        template!(List: "address, kcfi, memory, thread"), DuplicatesOk,
236        experimental!(no_sanitize)
237    ),
238    gated!(coverage, Normal, template!(Word, List: "on|off"), WarnFollowing, coverage_attribute, experimental!(coverage)),
239
240    ungated!(
241        doc, Normal, template!(List: "hidden|inline|...", NameValueStr: "string"), DuplicatesOk
242    ),
243
244    // Debugging
245    ungated!(
246        debugger_visualizer, Normal,
247        template!(List: r#"natvis_file = "...", gdb_script_file = "...""#), DuplicatesOk
248    ),
249
250    // ==========================================================================
251    // Unstable attributes:
252    // ==========================================================================
253
254    // Linking:
255    gated!(
256        naked, Normal, template!(Word), WarnFollowing, @only_local: true,
257        naked_functions, experimental!(naked)
258    ),
259
260    // Testing:
261    gated!(
262        test_runner, CrateLevel, template!(List: "path"), ErrorFollowing, custom_test_frameworks,
263        "custom test frameworks are an unstable feature",
264    ),
265
266    gated!(
267        reexport_test_harness_main, CrateLevel, template!(NameValueStr: "name"),
268        ErrorFollowing, custom_test_frameworks,
269        "custom test frameworks are an unstable feature",
270    ),
271
272    // RFC #1268
273    gated!(
274        marker, Normal, template!(Word), WarnFollowing, @only_local: true,
275        marker_trait_attr, experimental!(marker)
276    ),
277    gated!(
278        thread_local, Normal, template!(Word), WarnFollowing,
279        "`#[thread_local]` is an experimental feature, and does not currently handle destructors",
280    ),
281    gated!(no_core, CrateLevel, template!(Word), WarnFollowing, experimental!(no_core)),
282    // RFC 2412
283    ungated!(
284        optimize, Normal, template!(List: "size|speed|none"), ErrorPreceding
285    ),
286
287    gated!(ffi_pure, Normal, template!(Word), WarnFollowing, experimental!(ffi_pure)),
288    gated!(ffi_const, Normal, template!(Word), WarnFollowing, experimental!(ffi_const)),
289    gated!(
290        register_tool, CrateLevel, template!(List: "tool1, tool2, ..."), DuplicatesOk,
291        experimental!(register_tool),
292    ),
293
294    gated!(
295        cmse_nonsecure_entry, Normal, template!(Word), WarnFollowing,
296        experimental!(cmse_nonsecure_entry)
297    ),
298    // RFC 2632
299    gated!(
300        const_trait, Normal, template!(Word), WarnFollowing, const_trait_impl,
301        "`const_trait` is a temporary placeholder for marking a trait that is suitable for `const` \
302        `impls` and all default bodies as `const`, which may be removed or renamed in the \
303        future."
304    ),
305    // lang-team MCP 147
306    gated!(
307        deprecated_safe, Normal, template!(List: r#"since = "version", note = "...""#), ErrorFollowing,
308        experimental!(deprecated_safe),
309    ),
310
311    // `#[collapse_debuginfo]`
312    gated!(
313        collapse_debuginfo, Normal, template!(Word), WarnFollowing,
314        experimental!(collapse_debuginfo)
315    ),
316
317    // RFC 2397
318    gated!(do_not_recommend, Normal, template!(Word), WarnFollowing, experimental!(do_not_recommend)),
319
320    // `#[cfi_encoding = ""]`
321    gated!(
322        cfi_encoding, Normal, template!(NameValueStr: "encoding"), ErrorPreceding,
323        experimental!(cfi_encoding)
324    ),
325
326    // ==========================================================================
327    // Internal attributes: Stability, deprecation, and unsafe:
328    // ==========================================================================
329
330    ungated!(
331        feature, CrateLevel,
332        template!(List: "name1, name2, ..."), DuplicatesOk, @only_local: true,
333    ),
334    // DuplicatesOk since it has its own validation
335    ungated!(
336        stable, Normal,
337        template!(List: r#"feature = "name", since = "version""#), DuplicatesOk, @only_local: true,
338    ),
339    ungated!(
340        unstable, Normal,
341        template!(List: r#"feature = "name", reason = "...", issue = "N""#), DuplicatesOk,
342    ),
343    ungated!(rustc_const_unstable, Normal, template!(List: r#"feature = "name""#), DuplicatesOk),
344    ungated!(
345        rustc_const_stable, Normal,
346        template!(List: r#"feature = "name""#), DuplicatesOk, @only_local: true,
347    ),
348    ungated!(
349        rustc_default_body_unstable, Normal,
350        template!(List: r#"feature = "name", reason = "...", issue = "N""#), DuplicatesOk
351    ),
352    gated!(
353        allow_internal_unstable, Normal, template!(Word, List: "feat1, feat2, ..."), DuplicatesOk,
354        "allow_internal_unstable side-steps feature gating and stability checks",
355    ),
356    gated!(
357        rustc_allow_const_fn_unstable, Normal,
358        template!(Word, List: "feat1, feat2, ..."), DuplicatesOk,
359        "rustc_allow_const_fn_unstable side-steps feature gating and stability checks"
360    ),
361    gated!(
362        allow_internal_unsafe, Normal, template!(Word), WarnFollowing,
363        "allow_internal_unsafe side-steps the unsafe_code lint",
364    ),
365    rustc_attr!(rustc_allowed_through_unstable_modules, Normal, template!(Word), WarnFollowing,
366    "rustc_allowed_through_unstable_modules special cases accidental stabilizations of stable items \
367    through unstable paths"),
368
369    // ==========================================================================
370    // Internal attributes: Type system related:
371    // ==========================================================================
372
373    gated!(fundamental, Normal, template!(Word), WarnFollowing, experimental!(fundamental)),
374    gated!(
375        may_dangle, Normal, template!(Word), WarnFollowing, dropck_eyepatch,
376        "`may_dangle` has unstable semantics and may be removed in the future",
377    ),
378
379    // ==========================================================================
380    // Internal attributes: Runtime related:
381    // ==========================================================================
382
383    rustc_attr!(rustc_allocator, Normal, template!(Word), WarnFollowing, IMPL_DETAIL),
384    rustc_attr!(rustc_nounwind, Normal, template!(Word), WarnFollowing, IMPL_DETAIL),
385    rustc_attr!(rustc_reallocator, Normal, template!(Word), WarnFollowing, IMPL_DETAIL),
386    rustc_attr!(rustc_deallocator, Normal, template!(Word), WarnFollowing, IMPL_DETAIL),
387    rustc_attr!(rustc_allocator_zeroed, Normal, template!(Word), WarnFollowing, IMPL_DETAIL),
388    gated!(
389        default_lib_allocator, Normal, template!(Word), WarnFollowing, allocator_internals,
390        experimental!(default_lib_allocator),
391    ),
392    gated!(
393        needs_allocator, Normal, template!(Word), WarnFollowing, allocator_internals,
394        experimental!(needs_allocator),
395    ),
396    gated!(panic_runtime, Normal, template!(Word), WarnFollowing, experimental!(panic_runtime)),
397    gated!(
398        needs_panic_runtime, Normal, template!(Word), WarnFollowing,
399        experimental!(needs_panic_runtime)
400    ),
401    gated!(
402        compiler_builtins, Normal, template!(Word), WarnFollowing,
403        "the `#[compiler_builtins]` attribute is used to identify the `compiler_builtins` crate \
404        which contains compiler-rt intrinsics and will never be stable",
405    ),
406    gated!(
407        profiler_runtime, Normal, template!(Word), WarnFollowing,
408        "the `#[profiler_runtime]` attribute is used to identify the `profiler_builtins` crate \
409        which contains the profiler runtime and will never be stable",
410    ),
411
412    // ==========================================================================
413    // Internal attributes, Linkage:
414    // ==========================================================================
415
416    gated!(
417        linkage, Normal, template!(NameValueStr: "external|internal|..."), ErrorPreceding, @only_local: true,
418        "the `linkage` attribute is experimental and not portable across platforms",
419    ),
420    rustc_attr!(
421        rustc_std_internal_symbol, Normal, template!(Word), WarnFollowing, @only_local: true, INTERNAL_UNSTABLE
422    ),
423
424    // ==========================================================================
425    // Internal attributes, Macro related:
426    // ==========================================================================
427
428    rustc_attr!(
429        rustc_builtin_macro, Normal,
430        template!(Word, List: "name, /*opt*/ attributes(name1, name2, ...)"), ErrorFollowing,
431        IMPL_DETAIL,
432    ),
433    rustc_attr!(rustc_proc_macro_decls, Normal, template!(Word), WarnFollowing, INTERNAL_UNSTABLE),
434    rustc_attr!(
435        rustc_macro_transparency, Normal,
436        template!(NameValueStr: "transparent|semiopaque|opaque"), ErrorFollowing,
437        "used internally for testing macro hygiene",
438    ),
439
440    // ==========================================================================
441    // Internal attributes, Diagnostics related:
442    // ==========================================================================
443
444    rustc_attr!(
445        rustc_on_unimplemented, Normal,
446        template!(
447            List: r#"/*opt*/ message = "...", /*opt*/ label = "...", /*opt*/ note = "...""#,
448            NameValueStr: "message"
449        ),
450        ErrorFollowing,
451        INTERNAL_UNSTABLE
452    ),
453    rustc_attr!(
454        rustc_confusables, Normal,
455        template!(List: r#""name1", "name2", ..."#),
456        ErrorFollowing,
457        INTERNAL_UNSTABLE,
458    ),
459    // Enumerates "identity-like" conversion methods to suggest on type mismatch.
460    rustc_attr!(
461        rustc_conversion_suggestion, Normal, template!(Word), WarnFollowing, INTERNAL_UNSTABLE
462    ),
463    // Prevents field reads in the marked trait or method to be considered
464    // during dead code analysis.
465    rustc_attr!(
466        rustc_trivial_field_reads, Normal, template!(Word), WarnFollowing, INTERNAL_UNSTABLE
467    ),
468    // Used by the `rustc::potential_query_instability` lint to warn methods which
469    // might not be stable during incremental compilation.
470    rustc_attr!(rustc_lint_query_instability, Normal, template!(Word), WarnFollowing, INTERNAL_UNSTABLE),
471    // Used by the `rustc::untracked_query_information` lint to warn methods which
472    // might break incremental compilation.
473    rustc_attr!(rustc_lint_untracked_query_information, Normal, template!(Word), WarnFollowing, INTERNAL_UNSTABLE),
474    // Used by the `rustc::bad_opt_access` lint to identify `DebuggingOptions` and `CodegenOptions`
475    // types (as well as any others in future).
476    rustc_attr!(rustc_lint_opt_ty, Normal, template!(Word), WarnFollowing, INTERNAL_UNSTABLE),
477    // Used by the `rustc::bad_opt_access` lint on fields
478    // types (as well as any others in future).
479    rustc_attr!(rustc_lint_opt_deny_field_access, Normal, template!(List: "message"), WarnFollowing, INTERNAL_UNSTABLE),
480
481    // ==========================================================================
482    // Internal attributes, Const related:
483    // ==========================================================================
484
485    rustc_attr!(rustc_promotable, Normal, template!(Word), WarnFollowing, IMPL_DETAIL),
486    rustc_attr!(
487        rustc_legacy_const_generics, Normal, template!(List: "N"), ErrorFollowing,
488        INTERNAL_UNSTABLE
489    ),
490    // Do not const-check this function's body. It will always get replaced during CTFE via `hook_special_const_fn`.
491    rustc_attr!(
492        rustc_do_not_const_check, Normal, template!(Word), WarnFollowing, INTERNAL_UNSTABLE
493    ),
494    // Ensure the argument to this function is &&str during const-check.
495    rustc_attr!(
496        rustc_const_panic_str, Normal, template!(Word), WarnFollowing, INTERNAL_UNSTABLE
497    ),
498
499    // ==========================================================================
500    // Internal attributes, Layout related:
501    // ==========================================================================
502
503    rustc_attr!(
504        rustc_layout_scalar_valid_range_start, Normal, template!(List: "value"), ErrorFollowing,
505        "the `#[rustc_layout_scalar_valid_range_start]` attribute is just used to enable \
506        niche optimizations in libcore and libstd and will never be stable",
507    ),
508    rustc_attr!(
509        rustc_layout_scalar_valid_range_end, Normal, template!(List: "value"), ErrorFollowing,
510        "the `#[rustc_layout_scalar_valid_range_end]` attribute is just used to enable \
511        niche optimizations in libcore and libstd and will never be stable",
512    ),
513    rustc_attr!(
514        rustc_nonnull_optimization_guaranteed, Normal, template!(Word), WarnFollowing,
515        "the `#[rustc_nonnull_optimization_guaranteed]` attribute is just used to enable \
516        niche optimizations in libcore and libstd and will never be stable",
517    ),
518
519    // ==========================================================================
520    // Internal attributes, Misc:
521    // ==========================================================================
522    gated!(
523        lang, Normal, template!(NameValueStr: "name"), DuplicatesOk, @only_local: true, lang_items,
524        "language items are subject to change",
525    ),
526    rustc_attr!(
527        rustc_pass_by_value, Normal, template!(Word), ErrorFollowing,
528        "#[rustc_pass_by_value] is used to mark types that must be passed by value instead of reference."
529    ),
530    rustc_attr!(
531        rustc_never_returns_null_ptr, Normal, template!(Word), ErrorFollowing,
532        "#[rustc_never_returns_null_ptr] is used to mark functions returning non-null pointers."
533    ),
534    rustc_attr!(
535        rustc_coherence_is_core, AttributeType::CrateLevel, template!(Word), ErrorFollowing, @only_local: true,
536        "#![rustc_coherence_is_core] allows inherent methods on builtin types, only intended to be used in `core`."
537    ),
538    rustc_attr!(
539        rustc_coinductive, AttributeType::Normal, template!(Word), WarnFollowing, @only_local: true,
540        "#![rustc_coinductive] changes a trait to be coinductive, allowing cycles in the trait solver."
541    ),
542    rustc_attr!(
543        rustc_allow_incoherent_impl, AttributeType::Normal, template!(Word), ErrorFollowing, @only_local: true,
544        "#[rustc_allow_incoherent_impl] has to be added to all impl items of an incoherent inherent impl."
545    ),
546    rustc_attr!(
547        rustc_deny_explicit_impl,
548        AttributeType::Normal,
549        template!(List: "implement_via_object = (true|false)"),
550        ErrorFollowing,
551        @only_local: true,
552        "#[rustc_deny_explicit_impl] enforces that a trait can have no user-provided impls"
553    ),
554    rustc_attr!(
555        rustc_has_incoherent_inherent_impls, AttributeType::Normal, template!(Word), ErrorFollowing,
556        "#[rustc_has_incoherent_inherent_impls] allows the addition of incoherent inherent impls for \
557         the given type by annotating all impl items with #[rustc_allow_incoherent_impl]."
558    ),
559    rustc_attr!(
560        rustc_box, AttributeType::Normal, template!(Word), ErrorFollowing,
561        "#[rustc_box] allows creating boxes \
562        and it is only intended to be used in `alloc`."
563    ),
564
565    BuiltinAttribute {
566        // name: sym::rustc_diagnostic_item,
567        name: "rustc_diagnostic_item",
568        // FIXME: This can be `true` once we always use `tcx.is_diagnostic_item`.
569        // only_local: false,
570        // type_: Normal,
571        template: template!(NameValueStr: "name"),
572        // duplicates: ErrorFollowing,
573        // gate: Gated(
574            // Stability::Unstable,
575            // sym::rustc_attrs,
576            // "diagnostic items compiler internal support for linting",
577            // cfg_fn!(rustc_attrs),
578        // ),
579    },
580    gated!(
581        // Used in resolve:
582        prelude_import, Normal, template!(Word), WarnFollowing,
583        "`#[prelude_import]` is for use by rustc only",
584    ),
585    gated!(
586        rustc_paren_sugar, Normal, template!(Word), WarnFollowing, unboxed_closures,
587        "unboxed_closures are still evolving",
588    ),
589    rustc_attr!(
590        rustc_inherit_overflow_checks, Normal, template!(Word), WarnFollowing, @only_local: true,
591        "the `#[rustc_inherit_overflow_checks]` attribute is just used to control \
592        overflow checking behavior of several libcore functions that are inlined \
593        across crates and will never be stable",
594    ),
595    rustc_attr!(
596        rustc_reservation_impl, Normal,
597        template!(NameValueStr: "reservation message"), ErrorFollowing,
598        "the `#[rustc_reservation_impl]` attribute is internally used \
599         for reserving for `for<T> From<!> for T` impl"
600    ),
601    rustc_attr!(
602        rustc_test_marker, Normal, template!(NameValueStr: "name"), WarnFollowing,
603        "the `#[rustc_test_marker]` attribute is used internally to track tests",
604    ),
605    rustc_attr!(
606        rustc_unsafe_specialization_marker, Normal, template!(Word), WarnFollowing,
607        "the `#[rustc_unsafe_specialization_marker]` attribute is used to check specializations"
608    ),
609    rustc_attr!(
610        rustc_specialization_trait, Normal, template!(Word), WarnFollowing,
611        "the `#[rustc_specialization_trait]` attribute is used to check specializations"
612    ),
613    rustc_attr!(
614        rustc_main, Normal, template!(Word), WarnFollowing,
615        "the `#[rustc_main]` attribute is used internally to specify test entry point function",
616    ),
617    rustc_attr!(
618        rustc_skip_array_during_method_dispatch, Normal, template!(Word), WarnFollowing,
619        "the `#[rustc_skip_array_during_method_dispatch]` attribute is used to exclude a trait \
620        from method dispatch when the receiver is an array, for compatibility in editions < 2021."
621    ),
622    rustc_attr!(
623        rustc_must_implement_one_of, Normal, template!(List: "function1, function2, ..."), ErrorFollowing,
624        "the `#[rustc_must_implement_one_of]` attribute is used to change minimal complete \
625        definition of a trait, it's currently in experimental form and should be changed before \
626        being exposed outside of the std"
627    ),
628    rustc_attr!(
629        rustc_doc_primitive, Normal, template!(NameValueStr: "primitive name"), ErrorFollowing,
630        r#"`rustc_doc_primitive` is a rustc internal attribute"#,
631    ),
632    rustc_attr!(
633        rustc_safe_intrinsic, Normal, template!(Word), WarnFollowing,
634        "the `#[rustc_safe_intrinsic]` attribute is used internally to mark intrinsics as safe"
635    ),
636    rustc_attr!(
637        rustc_intrinsic, Normal, template!(Word), ErrorFollowing,
638        "the `#[rustc_intrinsic]` attribute is used to declare intrinsics with function bodies",
639    ),
640    rustc_attr!(
641        rustc_no_mir_inline, Normal, template!(Word), WarnFollowing,
642        "#[rustc_no_mir_inline] prevents the MIR inliner from inlining a function while not affecting codegen"
643    ),
644    rustc_attr!(
645        rustc_intrinsic_must_be_overridden, Normal, template!(Word), ErrorFollowing,
646        "the `#[rustc_intrinsic_must_be_overridden]` attribute is used to declare intrinsics without real bodies",
647    ),
648
649    rustc_attr!(
650        rustc_deprecated_safe_2024, Normal, template!(Word), WarnFollowing,
651        "the `#[rustc_safe_intrinsic]` marks functions as unsafe in Rust 2024",
652    ),
653
654    // ==========================================================================
655    // Internal attributes, Testing:
656    // ==========================================================================
657
658    rustc_attr!(TEST, rustc_effective_visibility, Normal, template!(Word), WarnFollowing),
659    rustc_attr!(TEST, rustc_outlives, Normal, template!(Word), WarnFollowing),
660    rustc_attr!(TEST, rustc_capture_analysis, Normal, template!(Word), WarnFollowing),
661    rustc_attr!(TEST, rustc_insignificant_dtor, Normal, template!(Word), WarnFollowing),
662    rustc_attr!(TEST, rustc_strict_coherence, Normal, template!(Word), WarnFollowing),
663    rustc_attr!(TEST, rustc_variance, Normal, template!(Word), WarnFollowing),
664    rustc_attr!(TEST, rustc_variance_of_opaques, Normal, template!(Word), WarnFollowing),
665    rustc_attr!(TEST, rustc_hidden_type_of_opaques, Normal, template!(Word), WarnFollowing),
666    rustc_attr!(TEST, rustc_layout, Normal, template!(List: "field1, field2, ..."), WarnFollowing),
667    rustc_attr!(TEST, rustc_abi, Normal, template!(List: "field1, field2, ..."), WarnFollowing),
668    rustc_attr!(TEST, rustc_regions, Normal, template!(Word), WarnFollowing),
669    rustc_attr!(TEST, rustc_dump_user_args, Normal, template!(Word), WarnFollowing),
670    rustc_attr!(TEST, rustc_evaluate_where_clauses, Normal, template!(Word), WarnFollowing),
671    rustc_attr!(
672        TEST, rustc_if_this_changed, Normal, template!(Word, List: "DepNode"), DuplicatesOk
673    ),
674    rustc_attr!(
675        TEST, rustc_then_this_would_need, Normal, template!(List: "DepNode"), DuplicatesOk
676    ),
677    rustc_attr!(
678        TEST, rustc_clean, Normal,
679        template!(List: r#"cfg = "...", /*opt*/ label = "...", /*opt*/ except = "...""#),
680        DuplicatesOk,
681    ),
682    rustc_attr!(
683        TEST, rustc_partition_reused, Normal,
684        template!(List: r#"cfg = "...", module = "...""#), DuplicatesOk,
685    ),
686    rustc_attr!(
687        TEST, rustc_partition_codegened, Normal,
688        template!(List: r#"cfg = "...", module = "...""#), DuplicatesOk,
689    ),
690    rustc_attr!(
691        TEST, rustc_expected_cgu_reuse, Normal,
692        template!(List: r#"cfg = "...", module = "...", kind = "...""#), DuplicatesOk,
693    ),
694    rustc_attr!(TEST, rustc_symbol_name, Normal, template!(Word), WarnFollowing),
695    rustc_attr!(TEST, rustc_def_path, Normal, template!(Word), WarnFollowing),
696    rustc_attr!(TEST, rustc_mir, Normal, template!(List: "arg1, arg2, ..."), DuplicatesOk),
697    gated!(
698        custom_mir, Normal, template!(List: r#"dialect = "...", phase = "...""#),
699        ErrorFollowing, "the `#[custom_mir]` attribute is just used for the Rust test suite",
700    ),
701    rustc_attr!(TEST, rustc_dump_program_clauses, Normal, template!(Word), WarnFollowing),
702    rustc_attr!(TEST, rustc_dump_env_program_clauses, Normal, template!(Word), WarnFollowing),
703    rustc_attr!(TEST, rustc_object_lifetime_default, Normal, template!(Word), WarnFollowing),
704    rustc_attr!(TEST, rustc_dyn_incompatible_trait, Normal, template!(Word), WarnFollowing),
705    rustc_attr!(TEST, rustc_dump_vtable, Normal, template!(Word), WarnFollowing),
706    rustc_attr!(TEST, rustc_dummy, Normal, template!(Word /* doesn't matter*/), DuplicatesOk),
707    gated!(
708        omit_gdb_pretty_printer_section, Normal, template!(Word), WarnFollowing,
709        "the `#[omit_gdb_pretty_printer_section]` attribute is just used for the Rust test suite",
710    ),
711];
hir_expand/inert_attr_macro.rs

hir_expand/
inert_attr_macro.rs
