1 //! # Lints in the Rust compiler
3 //! This currently only contains the definitions and implementations
4 //! of most of the lints that `rustc` supports directly, it does not
5 //! contain the infrastructure for defining/registering lints. That is
6 //! available in `rustc::lint` and `rustc_driver::plugin` respectively.
10 //! This API is completely unstable and subject to change.
12 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")]
14 #![cfg_attr(test, feature(test))]
15 #![feature(box_patterns)]
16 #![feature(box_syntax)]
18 #![feature(rustc_diagnostic_macros)]
20 #![recursion_limit="256"]
26 mod nonstandard_style;
27 mod redundant_semicolon;
34 use rustc::lint::{EarlyContext, LateContext, LateLintPass, EarlyLintPass, LintPass, LintArray};
35 use rustc::lint::builtin::{
37 ABSOLUTE_PATHS_NOT_STARTING_WITH_CRATE,
38 ELIDED_LIFETIMES_IN_PATHS,
39 EXPLICIT_OUTLIVES_REQUIREMENTS,
40 INTRA_DOC_LINK_RESOLUTION_FAILURE,
41 MISSING_DOC_CODE_EXAMPLES,
43 parser::ILL_FORMED_ATTRIBUTE_INPUT,
47 use rustc::hir::def_id::DefId;
48 use rustc::ty::query::Providers;
49 use rustc::ty::TyCtxt;
52 use syntax::edition::Edition;
57 use lint::FutureIncompatibleInfo;
59 use redundant_semicolon::*;
60 use nonstandard_style::*;
64 use non_ascii_idents::*;
65 use rustc::lint::internal::*;
67 /// Useful for other parts of the compiler.
68 pub use builtin::SoftLints;
70 pub fn provide(providers: &mut Providers<'_>) {
71 *providers = Providers {
77 fn lint_mod(tcx: TyCtxt<'_>, module_def_id: DefId) {
78 lint::late_lint_mod(tcx, module_def_id, BuiltinCombinedModuleLateLintPass::new());
81 macro_rules! pre_expansion_lint_passes {
82 ($macro:path, $args:tt) => (
84 KeywordIdents: KeywordIdents,
85 UnusedDocComment: UnusedDocComment,
90 macro_rules! early_lint_passes {
91 ($macro:path, $args:tt) => (
93 UnusedParens: UnusedParens,
94 UnusedImportBraces: UnusedImportBraces,
95 UnsafeCode: UnsafeCode,
96 AnonymousParameters: AnonymousParameters,
97 EllipsisInclusiveRangePatterns: EllipsisInclusiveRangePatterns::default(),
98 NonCamelCaseTypes: NonCamelCaseTypes,
99 DeprecatedAttr: DeprecatedAttr::new(),
100 WhileTrue: WhileTrue,
101 NonAsciiIdents: NonAsciiIdents,
102 IncompleteFeatures: IncompleteFeatures,
103 RedundantSemicolon: RedundantSemicolon,
108 macro_rules! declare_combined_early_pass {
109 ([$name:ident], $passes:tt) => (
110 early_lint_methods!(declare_combined_early_lint_pass, [pub $name, $passes]);
114 pre_expansion_lint_passes!(declare_combined_early_pass, [BuiltinCombinedPreExpansionLintPass]);
115 early_lint_passes!(declare_combined_early_pass, [BuiltinCombinedEarlyLintPass]);
117 macro_rules! late_lint_passes {
118 ($macro:path, $args:tt) => (
120 // FIXME: Look into regression when this is used as a module lint
121 // May Depend on constants elsewhere
122 UnusedBrokenConst: UnusedBrokenConst,
124 // Uses attr::is_used which is untracked, can't be an incremental module pass.
125 UnusedAttributes: UnusedAttributes::new(),
127 // Needs to run after UnusedAttributes as it marks all `feature` attributes as used.
128 UnstableFeatures: UnstableFeatures,
130 // Tracks state across modules
131 UnnameableTestItems: UnnameableTestItems::new(),
133 // Tracks attributes of parents
134 MissingDoc: MissingDoc::new(),
136 // Depends on access levels
137 // FIXME: Turn the computation of types which implement Debug into a query
138 // and change this to a module lint pass
139 MissingDebugImplementations: MissingDebugImplementations::default(),
144 macro_rules! late_lint_mod_passes {
145 ($macro:path, $args:tt) => (
147 HardwiredLints: HardwiredLints,
148 ImproperCTypes: ImproperCTypes,
149 VariantSizeDifferences: VariantSizeDifferences,
150 BoxPointers: BoxPointers,
151 PathStatements: PathStatements,
153 // Depends on referenced function signatures in expressions
154 UnusedResults: UnusedResults,
156 NonUpperCaseGlobals: NonUpperCaseGlobals,
157 NonShorthandFieldPatterns: NonShorthandFieldPatterns,
158 UnusedAllocation: UnusedAllocation,
160 // Depends on types used in type definitions
161 MissingCopyImplementations: MissingCopyImplementations,
163 PluginAsLibrary: PluginAsLibrary,
165 // Depends on referenced function signatures in expressions
166 MutableTransmutes: MutableTransmutes,
168 // Depends on types of fields, checks if they implement Drop
169 UnionsWithDropFields: UnionsWithDropFields,
171 TypeAliasBounds: TypeAliasBounds,
173 TrivialConstraints: TrivialConstraints,
174 TypeLimits: TypeLimits::new(),
176 NonSnakeCase: NonSnakeCase,
177 InvalidNoMangleItems: InvalidNoMangleItems,
179 // Depends on access levels
180 UnreachablePub: UnreachablePub,
182 ExplicitOutlivesRequirements: ExplicitOutlivesRequirements,
183 InvalidValue: InvalidValue,
188 macro_rules! declare_combined_late_pass {
189 ([$v:vis $name:ident], $passes:tt) => (
190 late_lint_methods!(declare_combined_late_lint_pass, [$v $name, $passes], ['tcx]);
194 // FIXME: Make a separate lint type which do not require typeck tables
195 late_lint_passes!(declare_combined_late_pass, [pub BuiltinCombinedLateLintPass]);
197 late_lint_mod_passes!(declare_combined_late_pass, [BuiltinCombinedModuleLateLintPass]);
199 /// Tell the `LintStore` about all the built-in lints (the ones
200 /// defined in this crate and the ones defined in
201 /// `rustc::lint::builtin`).
202 pub fn register_builtins(store: &mut lint::LintStore, sess: Option<&Session>) {
203 macro_rules! add_lint_group {
204 ($sess:ident, $name:expr, $($lint:ident),*) => (
205 store.register_group($sess, false, $name, None, vec![$(LintId::of($lint)),*]);
209 macro_rules! register_pass {
210 ($method:ident, $constructor:expr, [$($args:expr),*]) => (
211 store.$method(sess, false, false, $($args,)* box $constructor);
215 macro_rules! register_passes {
216 ([$method:ident, $args:tt], [$($passes:ident: $constructor:expr,)*]) => (
218 register_pass!($method, $constructor, $args);
223 if sess.map(|sess| sess.opts.debugging_opts.no_interleave_lints).unwrap_or(false) {
224 pre_expansion_lint_passes!(register_passes, [register_pre_expansion_pass, []]);
225 early_lint_passes!(register_passes, [register_early_pass, []]);
226 late_lint_passes!(register_passes, [register_late_pass, [false]]);
227 late_lint_mod_passes!(register_passes, [register_late_pass, [true]]);
229 store.register_pre_expansion_pass(
233 box BuiltinCombinedPreExpansionLintPass::new()
235 store.register_early_pass(sess, false, true, box BuiltinCombinedEarlyLintPass::new());
236 store.register_late_pass(
237 sess, false, true, true, box BuiltinCombinedModuleLateLintPass::new()
239 store.register_late_pass(
240 sess, false, true, false, box BuiltinCombinedLateLintPass::new()
244 add_lint_group!(sess,
246 NON_CAMEL_CASE_TYPES,
248 NON_UPPER_CASE_GLOBALS);
250 add_lint_group!(sess,
258 UNREACHABLE_PATTERNS,
266 UNUSED_EXTERN_CRATES,
271 add_lint_group!(sess,
274 UNUSED_EXTERN_CRATES,
275 ELLIPSIS_INCLUSIVE_RANGE_PATTERNS,
276 ELIDED_LIFETIMES_IN_PATHS,
277 EXPLICIT_OUTLIVES_REQUIREMENTS
279 // FIXME(#52665, #47816) not always applicable and not all
280 // macros are ready for this yet.
283 // FIXME macro crates are not up for this yet, too much
284 // breakage is seen if we try to encourage this lint.
285 // MACRO_USE_EXTERN_CRATE,
288 add_lint_group!(sess,
290 INTRA_DOC_LINK_RESOLUTION_FAILURE,
291 MISSING_DOC_CODE_EXAMPLES,
294 // Guidelines for creating a future incompatibility lint:
296 // - Create a lint defaulting to warn as normal, with ideally the same error
297 // message you would normally give
298 // - Add a suitable reference, typically an RFC or tracking issue. Go ahead
299 // and include the full URL, sort items in ascending order of issue numbers.
300 // - Later, change lint to error
301 // - Eventually, remove lint
302 store.register_future_incompatible(sess, vec![
303 FutureIncompatibleInfo {
304 id: LintId::of(PRIVATE_IN_PUBLIC),
305 reference: "issue #34537 <https://github.com/rust-lang/rust/issues/34537>",
308 FutureIncompatibleInfo {
309 id: LintId::of(PUB_USE_OF_PRIVATE_EXTERN_CRATE),
310 reference: "issue #34537 <https://github.com/rust-lang/rust/issues/34537>",
313 FutureIncompatibleInfo {
314 id: LintId::of(PATTERNS_IN_FNS_WITHOUT_BODY),
315 reference: "issue #35203 <https://github.com/rust-lang/rust/issues/35203>",
318 FutureIncompatibleInfo {
319 id: LintId::of(DUPLICATE_MACRO_EXPORTS),
320 reference: "issue #35896 <https://github.com/rust-lang/rust/issues/35896>",
321 edition: Some(Edition::Edition2018),
323 FutureIncompatibleInfo {
324 id: LintId::of(KEYWORD_IDENTS),
325 reference: "issue #49716 <https://github.com/rust-lang/rust/issues/49716>",
326 edition: Some(Edition::Edition2018),
328 FutureIncompatibleInfo {
329 id: LintId::of(SAFE_EXTERN_STATICS),
330 reference: "issue #36247 <https://github.com/rust-lang/rust/issues/36247>",
333 FutureIncompatibleInfo {
334 id: LintId::of(INVALID_TYPE_PARAM_DEFAULT),
335 reference: "issue #36887 <https://github.com/rust-lang/rust/issues/36887>",
338 FutureIncompatibleInfo {
339 id: LintId::of(LEGACY_DIRECTORY_OWNERSHIP),
340 reference: "issue #37872 <https://github.com/rust-lang/rust/issues/37872>",
343 FutureIncompatibleInfo {
344 id: LintId::of(LEGACY_CONSTRUCTOR_VISIBILITY),
345 reference: "issue #39207 <https://github.com/rust-lang/rust/issues/39207>",
348 FutureIncompatibleInfo {
349 id: LintId::of(MISSING_FRAGMENT_SPECIFIER),
350 reference: "issue #40107 <https://github.com/rust-lang/rust/issues/40107>",
353 FutureIncompatibleInfo {
354 id: LintId::of(ILLEGAL_FLOATING_POINT_LITERAL_PATTERN),
355 reference: "issue #41620 <https://github.com/rust-lang/rust/issues/41620>",
358 FutureIncompatibleInfo {
359 id: LintId::of(ANONYMOUS_PARAMETERS),
360 reference: "issue #41686 <https://github.com/rust-lang/rust/issues/41686>",
361 edition: Some(Edition::Edition2018),
363 FutureIncompatibleInfo {
364 id: LintId::of(PARENTHESIZED_PARAMS_IN_TYPES_AND_MODULES),
365 reference: "issue #42238 <https://github.com/rust-lang/rust/issues/42238>",
368 FutureIncompatibleInfo {
369 id: LintId::of(LATE_BOUND_LIFETIME_ARGUMENTS),
370 reference: "issue #42868 <https://github.com/rust-lang/rust/issues/42868>",
373 FutureIncompatibleInfo {
374 id: LintId::of(SAFE_PACKED_BORROWS),
375 reference: "issue #46043 <https://github.com/rust-lang/rust/issues/46043>",
378 FutureIncompatibleInfo {
379 id: LintId::of(ORDER_DEPENDENT_TRAIT_OBJECTS),
380 reference: "issue #56484 <https://github.com/rust-lang/rust/issues/56484>",
383 FutureIncompatibleInfo {
384 id: LintId::of(TYVAR_BEHIND_RAW_POINTER),
385 reference: "issue #46906 <https://github.com/rust-lang/rust/issues/46906>",
386 edition: Some(Edition::Edition2018),
388 FutureIncompatibleInfo {
389 id: LintId::of(UNSTABLE_NAME_COLLISIONS),
390 reference: "issue #48919 <https://github.com/rust-lang/rust/issues/48919>",
392 // Note: this item represents future incompatibility of all unstable functions in the
393 // standard library, and thus should never be removed or changed to an error.
395 FutureIncompatibleInfo {
396 id: LintId::of(ABSOLUTE_PATHS_NOT_STARTING_WITH_CRATE),
397 reference: "issue #53130 <https://github.com/rust-lang/rust/issues/53130>",
398 edition: Some(Edition::Edition2018),
400 FutureIncompatibleInfo {
401 id: LintId::of(WHERE_CLAUSES_OBJECT_SAFETY),
402 reference: "issue #51443 <https://github.com/rust-lang/rust/issues/51443>",
405 FutureIncompatibleInfo {
406 id: LintId::of(PROC_MACRO_DERIVE_RESOLUTION_FALLBACK),
407 reference: "issue #50504 <https://github.com/rust-lang/rust/issues/50504>",
410 FutureIncompatibleInfo {
411 id: LintId::of(MACRO_EXPANDED_MACRO_EXPORTS_ACCESSED_BY_ABSOLUTE_PATHS),
412 reference: "issue #52234 <https://github.com/rust-lang/rust/issues/52234>",
415 FutureIncompatibleInfo {
416 id: LintId::of(ILL_FORMED_ATTRIBUTE_INPUT),
417 reference: "issue #57571 <https://github.com/rust-lang/rust/issues/57571>",
420 FutureIncompatibleInfo {
421 id: LintId::of(AMBIGUOUS_ASSOCIATED_ITEMS),
422 reference: "issue #57644 <https://github.com/rust-lang/rust/issues/57644>",
425 FutureIncompatibleInfo {
426 id: LintId::of(NESTED_IMPL_TRAIT),
427 reference: "issue #59014 <https://github.com/rust-lang/rust/issues/59014>",
430 FutureIncompatibleInfo {
431 id: LintId::of(MUTABLE_BORROW_RESERVATION_CONFLICT),
432 reference: "issue #59159 <https://github.com/rust-lang/rust/issues/59159>",
435 FutureIncompatibleInfo {
436 id: LintId::of(INDIRECT_STRUCTURAL_MATCH),
437 reference: "issue #62411 <https://github.com/rust-lang/rust/issues/62411>",
442 // Register renamed and removed lints.
443 store.register_renamed("single_use_lifetime", "single_use_lifetimes");
444 store.register_renamed("elided_lifetime_in_path", "elided_lifetimes_in_paths");
445 store.register_renamed("bare_trait_object", "bare_trait_objects");
446 store.register_renamed("unstable_name_collision", "unstable_name_collisions");
447 store.register_renamed("unused_doc_comment", "unused_doc_comments");
448 store.register_renamed("async_idents", "keyword_idents");
449 store.register_removed("unknown_features", "replaced by an error");
450 store.register_removed("unsigned_negation", "replaced by negate_unsigned feature gate");
451 store.register_removed("negate_unsigned", "cast a signed value instead");
452 store.register_removed("raw_pointer_derive", "using derive with raw pointers is ok");
453 // Register lint group aliases.
454 store.register_group_alias("nonstandard_style", "bad_style");
455 // This was renamed to `raw_pointer_derive`, which was then removed,
456 // so it is also considered removed.
457 store.register_removed("raw_pointer_deriving", "using derive with raw pointers is ok");
458 store.register_removed("drop_with_repr_extern", "drop flags have been removed");
459 store.register_removed("fat_ptr_transmutes", "was accidentally removed back in 2014");
460 store.register_removed("deprecated_attr", "use `deprecated` instead");
461 store.register_removed("transmute_from_fn_item_types",
462 "always cast functions before transmuting them");
463 store.register_removed("hr_lifetime_in_assoc_type",
464 "converted into hard error, see https://github.com/rust-lang/rust/issues/33685");
465 store.register_removed("inaccessible_extern_crate",
466 "converted into hard error, see https://github.com/rust-lang/rust/issues/36886");
467 store.register_removed("super_or_self_in_global_path",
468 "converted into hard error, see https://github.com/rust-lang/rust/issues/36888");
469 store.register_removed("overlapping_inherent_impls",
470 "converted into hard error, see https://github.com/rust-lang/rust/issues/36889");
471 store.register_removed("illegal_floating_point_constant_pattern",
472 "converted into hard error, see https://github.com/rust-lang/rust/issues/36890");
473 store.register_removed("illegal_struct_or_enum_constant_pattern",
474 "converted into hard error, see https://github.com/rust-lang/rust/issues/36891");
475 store.register_removed("lifetime_underscore",
476 "converted into hard error, see https://github.com/rust-lang/rust/issues/36892");
477 store.register_removed("extra_requirement_in_impl",
478 "converted into hard error, see https://github.com/rust-lang/rust/issues/37166");
479 store.register_removed("legacy_imports",
480 "converted into hard error, see https://github.com/rust-lang/rust/issues/38260");
481 store.register_removed("coerce_never",
482 "converted into hard error, see https://github.com/rust-lang/rust/issues/48950");
483 store.register_removed("resolve_trait_on_defaulted_unit",
484 "converted into hard error, see https://github.com/rust-lang/rust/issues/48950");
485 store.register_removed("private_no_mangle_fns",
486 "no longer a warning, `#[no_mangle]` functions always exported");
487 store.register_removed("private_no_mangle_statics",
488 "no longer a warning, `#[no_mangle]` statics always exported");
489 store.register_removed("bad_repr",
490 "replaced with a generic attribute input check");
491 store.register_removed("duplicate_matcher_binding_name",
492 "converted into hard error, see https://github.com/rust-lang/rust/issues/57742");
493 store.register_removed("incoherent_fundamental_impls",
494 "converted into hard error, see https://github.com/rust-lang/rust/issues/46205");
497 pub fn register_internals(store: &mut lint::LintStore, sess: Option<&Session>) {
498 store.register_early_pass(sess, false, false, box DefaultHashTypes::new());
499 store.register_early_pass(sess, false, false, box LintPassImpl);
500 store.register_late_pass(sess, false, false, false, box TyTyKind);
501 store.register_group(
507 LintId::of(DEFAULT_HASH_TYPES),
508 LintId::of(USAGE_OF_TY_TYKIND),
509 LintId::of(LINT_PASS_IMPL_WITHOUT_MACRO),
510 LintId::of(TY_PASS_BY_REFERENCE),
511 LintId::of(USAGE_OF_QUALIFIED_TY),