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Diffstat (limited to 'compiler/rustc_lint/src/lib.rs')
| -rw-r--r-- | compiler/rustc_lint/src/lib.rs | 538 |
1 files changed, 538 insertions, 0 deletions
diff --git a/compiler/rustc_lint/src/lib.rs b/compiler/rustc_lint/src/lib.rs new file mode 100644 index 000000000..389a0b5d1 --- /dev/null +++ b/compiler/rustc_lint/src/lib.rs @@ -0,0 +1,538 @@ +//! Lints, aka compiler warnings. +//! +//! A 'lint' check is a kind of miscellaneous constraint that a user _might_ +//! want to enforce, but might reasonably want to permit as well, on a +//! module-by-module basis. They contrast with static constraints enforced by +//! other phases of the compiler, which are generally required to hold in order +//! to compile the program at all. +//! +//! Most lints can be written as [LintPass] instances. These run after +//! all other analyses. The `LintPass`es built into rustc are defined +//! within [rustc_session::lint::builtin], +//! which has further comments on how to add such a lint. +//! rustc can also load user-defined lint plugins via the plugin mechanism. +//! +//! Some of rustc's lints are defined elsewhere in the compiler and work by +//! calling `add_lint()` on the overall `Session` object. This works when +//! it happens before the main lint pass, which emits the lints stored by +//! `add_lint()`. To emit lints after the main lint pass (from codegen, for +//! example) requires more effort. See `emit_lint` and `GatherNodeLevels` +//! in `context.rs`. +//! +//! Some code also exists in [rustc_session::lint], [rustc_middle::lint]. +//! +//! ## Note +//! +//! This API is completely unstable and subject to change. + +#![allow(rustc::potential_query_instability)] +#![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")] +#![feature(array_windows)] +#![feature(box_patterns)] +#![feature(control_flow_enum)] +#![feature(if_let_guard)] +#![feature(iter_intersperse)] +#![feature(iter_order_by)] +#![feature(let_chains)] +#![feature(let_else)] +#![feature(never_type)] +#![recursion_limit = "256"] + +#[macro_use] +extern crate rustc_middle; +#[macro_use] +extern crate rustc_session; + +mod array_into_iter; +pub mod builtin; +mod context; +mod early; +mod enum_intrinsics_non_enums; +mod expect; +pub mod hidden_unicode_codepoints; +mod internal; +mod late; +mod levels; +mod methods; +mod non_ascii_idents; +mod non_fmt_panic; +mod nonstandard_style; +mod noop_method_call; +mod pass_by_value; +mod passes; +mod redundant_semicolon; +mod traits; +mod types; +mod unused; + +pub use array_into_iter::ARRAY_INTO_ITER; + +use rustc_ast as ast; +use rustc_hir as hir; +use rustc_hir::def_id::LocalDefId; +use rustc_middle::ty::query::Providers; +use rustc_middle::ty::TyCtxt; +use rustc_session::lint::builtin::{ + BARE_TRAIT_OBJECTS, ELIDED_LIFETIMES_IN_PATHS, EXPLICIT_OUTLIVES_REQUIREMENTS, +}; +use rustc_span::symbol::Ident; +use rustc_span::Span; + +use array_into_iter::ArrayIntoIter; +use builtin::*; +use enum_intrinsics_non_enums::EnumIntrinsicsNonEnums; +use hidden_unicode_codepoints::*; +use internal::*; +use methods::*; +use non_ascii_idents::*; +use non_fmt_panic::NonPanicFmt; +use nonstandard_style::*; +use noop_method_call::*; +use pass_by_value::*; +use redundant_semicolon::*; +use traits::*; +use types::*; +use unused::*; + +/// Useful for other parts of the compiler / Clippy. +pub use builtin::SoftLints; +pub use context::{CheckLintNameResult, FindLintError, LintStore}; +pub use context::{EarlyContext, LateContext, LintContext}; +pub use early::{check_ast_node, EarlyCheckNode}; +pub use late::{check_crate, unerased_lint_store}; +pub use passes::{EarlyLintPass, LateLintPass}; +pub use rustc_session::lint::Level::{self, *}; +pub use rustc_session::lint::{BufferedEarlyLint, FutureIncompatibleInfo, Lint, LintId}; +pub use rustc_session::lint::{LintArray, LintPass}; + +pub fn provide(providers: &mut Providers) { + levels::provide(providers); + expect::provide(providers); + *providers = Providers { lint_mod, ..*providers }; +} + +fn lint_mod(tcx: TyCtxt<'_>, module_def_id: LocalDefId) { + late::late_lint_mod(tcx, module_def_id, BuiltinCombinedModuleLateLintPass::new()); +} + +macro_rules! pre_expansion_lint_passes { + ($macro:path, $args:tt) => { + $macro!($args, [KeywordIdents: KeywordIdents,]); + }; +} + +macro_rules! early_lint_passes { + ($macro:path, $args:tt) => { + $macro!( + $args, + [ + UnusedParens: UnusedParens, + UnusedBraces: UnusedBraces, + UnusedImportBraces: UnusedImportBraces, + UnsafeCode: UnsafeCode, + AnonymousParameters: AnonymousParameters, + EllipsisInclusiveRangePatterns: EllipsisInclusiveRangePatterns::default(), + NonCamelCaseTypes: NonCamelCaseTypes, + DeprecatedAttr: DeprecatedAttr::new(), + WhileTrue: WhileTrue, + NonAsciiIdents: NonAsciiIdents, + HiddenUnicodeCodepoints: HiddenUnicodeCodepoints, + IncompleteFeatures: IncompleteFeatures, + RedundantSemicolons: RedundantSemicolons, + UnusedDocComment: UnusedDocComment, + ] + ); + }; +} + +macro_rules! declare_combined_early_pass { + ([$name:ident], $passes:tt) => ( + early_lint_methods!(declare_combined_early_lint_pass, [pub $name, $passes]); + ) +} + +pre_expansion_lint_passes!(declare_combined_early_pass, [BuiltinCombinedPreExpansionLintPass]); +early_lint_passes!(declare_combined_early_pass, [BuiltinCombinedEarlyLintPass]); + +macro_rules! late_lint_passes { + ($macro:path, $args:tt) => { + $macro!( + $args, + [ + // Tracks state across modules + UnnameableTestItems: UnnameableTestItems::new(), + // Tracks attributes of parents + MissingDoc: MissingDoc::new(), + // Builds a global list of all impls of `Debug`. + // FIXME: Turn the computation of types which implement Debug into a query + // and change this to a module lint pass + MissingDebugImplementations: MissingDebugImplementations::default(), + // Keeps a global list of foreign declarations. + ClashingExternDeclarations: ClashingExternDeclarations::new(), + ] + ); + }; +} + +macro_rules! late_lint_mod_passes { + ($macro:path, $args:tt) => { + $macro!( + $args, + [ + HardwiredLints: HardwiredLints, + ImproperCTypesDeclarations: ImproperCTypesDeclarations, + ImproperCTypesDefinitions: ImproperCTypesDefinitions, + VariantSizeDifferences: VariantSizeDifferences, + BoxPointers: BoxPointers, + PathStatements: PathStatements, + // Depends on referenced function signatures in expressions + UnusedResults: UnusedResults, + NonUpperCaseGlobals: NonUpperCaseGlobals, + NonShorthandFieldPatterns: NonShorthandFieldPatterns, + UnusedAllocation: UnusedAllocation, + // Depends on types used in type definitions + MissingCopyImplementations: MissingCopyImplementations, + // Depends on referenced function signatures in expressions + MutableTransmutes: MutableTransmutes, + TypeAliasBounds: TypeAliasBounds, + TrivialConstraints: TrivialConstraints, + TypeLimits: TypeLimits::new(), + NonSnakeCase: NonSnakeCase, + InvalidNoMangleItems: InvalidNoMangleItems, + // Depends on access levels + UnreachablePub: UnreachablePub, + ExplicitOutlivesRequirements: ExplicitOutlivesRequirements, + InvalidValue: InvalidValue, + DerefNullPtr: DerefNullPtr, + // May Depend on constants elsewhere + UnusedBrokenConst: UnusedBrokenConst, + UnstableFeatures: UnstableFeatures, + ArrayIntoIter: ArrayIntoIter::default(), + DropTraitConstraints: DropTraitConstraints, + TemporaryCStringAsPtr: TemporaryCStringAsPtr, + NonPanicFmt: NonPanicFmt, + NoopMethodCall: NoopMethodCall, + EnumIntrinsicsNonEnums: EnumIntrinsicsNonEnums, + InvalidAtomicOrdering: InvalidAtomicOrdering, + NamedAsmLabels: NamedAsmLabels, + ] + ); + }; +} + +macro_rules! declare_combined_late_pass { + ([$v:vis $name:ident], $passes:tt) => ( + late_lint_methods!(declare_combined_late_lint_pass, [$v $name, $passes], ['tcx]); + ) +} + +// FIXME: Make a separate lint type which do not require typeck tables +late_lint_passes!(declare_combined_late_pass, [pub BuiltinCombinedLateLintPass]); + +late_lint_mod_passes!(declare_combined_late_pass, [BuiltinCombinedModuleLateLintPass]); + +pub fn new_lint_store(no_interleave_lints: bool, internal_lints: bool) -> LintStore { + let mut lint_store = LintStore::new(); + + register_builtins(&mut lint_store, no_interleave_lints); + if internal_lints { + register_internals(&mut lint_store); + } + + lint_store +} + +/// Tell the `LintStore` about all the built-in lints (the ones +/// defined in this crate and the ones defined in +/// `rustc_session::lint::builtin`). +fn register_builtins(store: &mut LintStore, no_interleave_lints: bool) { + macro_rules! add_lint_group { + ($name:expr, $($lint:ident),*) => ( + store.register_group(false, $name, None, vec![$(LintId::of($lint)),*]); + ) + } + + macro_rules! register_pass { + ($method:ident, $ty:ident, $constructor:expr) => { + store.register_lints(&$ty::get_lints()); + store.$method(|| Box::new($constructor)); + }; + } + + macro_rules! register_passes { + ($method:ident, [$($passes:ident: $constructor:expr,)*]) => ( + $( + register_pass!($method, $passes, $constructor); + )* + ) + } + + if no_interleave_lints { + pre_expansion_lint_passes!(register_passes, register_pre_expansion_pass); + early_lint_passes!(register_passes, register_early_pass); + late_lint_passes!(register_passes, register_late_pass); + late_lint_mod_passes!(register_passes, register_late_mod_pass); + } else { + store.register_lints(&BuiltinCombinedPreExpansionLintPass::get_lints()); + store.register_lints(&BuiltinCombinedEarlyLintPass::get_lints()); + store.register_lints(&BuiltinCombinedModuleLateLintPass::get_lints()); + store.register_lints(&BuiltinCombinedLateLintPass::get_lints()); + } + + add_lint_group!( + "nonstandard_style", + NON_CAMEL_CASE_TYPES, + NON_SNAKE_CASE, + NON_UPPER_CASE_GLOBALS + ); + + add_lint_group!( + "unused", + UNUSED_IMPORTS, + UNUSED_VARIABLES, + UNUSED_ASSIGNMENTS, + DEAD_CODE, + UNUSED_MUT, + UNREACHABLE_CODE, + UNREACHABLE_PATTERNS, + UNUSED_MUST_USE, + UNUSED_UNSAFE, + PATH_STATEMENTS, + UNUSED_ATTRIBUTES, + UNUSED_MACROS, + UNUSED_MACRO_RULES, + UNUSED_ALLOCATION, + UNUSED_DOC_COMMENTS, + UNUSED_EXTERN_CRATES, + UNUSED_FEATURES, + UNUSED_LABELS, + UNUSED_PARENS, + UNUSED_BRACES, + REDUNDANT_SEMICOLONS + ); + + add_lint_group!( + "rust_2018_idioms", + BARE_TRAIT_OBJECTS, + UNUSED_EXTERN_CRATES, + ELLIPSIS_INCLUSIVE_RANGE_PATTERNS, + ELIDED_LIFETIMES_IN_PATHS, + EXPLICIT_OUTLIVES_REQUIREMENTS // FIXME(#52665, #47816) not always applicable and not all + // macros are ready for this yet. + // UNREACHABLE_PUB, + + // FIXME macro crates are not up for this yet, too much + // breakage is seen if we try to encourage this lint. + // MACRO_USE_EXTERN_CRATE + ); + + // Register renamed and removed lints. + store.register_renamed("single_use_lifetime", "single_use_lifetimes"); + store.register_renamed("elided_lifetime_in_path", "elided_lifetimes_in_paths"); + store.register_renamed("bare_trait_object", "bare_trait_objects"); + store.register_renamed("unstable_name_collision", "unstable_name_collisions"); + store.register_renamed("unused_doc_comment", "unused_doc_comments"); + store.register_renamed("async_idents", "keyword_idents"); + store.register_renamed("exceeding_bitshifts", "arithmetic_overflow"); + store.register_renamed("redundant_semicolon", "redundant_semicolons"); + store.register_renamed("overlapping_patterns", "overlapping_range_endpoints"); + store.register_renamed("safe_packed_borrows", "unaligned_references"); + store.register_renamed("disjoint_capture_migration", "rust_2021_incompatible_closure_captures"); + store.register_renamed("or_patterns_back_compat", "rust_2021_incompatible_or_patterns"); + store.register_renamed("non_fmt_panic", "non_fmt_panics"); + + // These were moved to tool lints, but rustc still sees them when compiling normally, before + // tool lints are registered, so `check_tool_name_for_backwards_compat` doesn't work. Use + // `register_removed` explicitly. + const RUSTDOC_LINTS: &[&str] = &[ + "broken_intra_doc_links", + "private_intra_doc_links", + "missing_crate_level_docs", + "missing_doc_code_examples", + "private_doc_tests", + "invalid_codeblock_attributes", + "invalid_html_tags", + "non_autolinks", + ]; + for rustdoc_lint in RUSTDOC_LINTS { + store.register_ignored(rustdoc_lint); + } + store.register_removed( + "intra_doc_link_resolution_failure", + "use `rustdoc::broken_intra_doc_links` instead", + ); + store.register_removed("rustdoc", "use `rustdoc::all` instead"); + + store.register_removed("unknown_features", "replaced by an error"); + store.register_removed("unsigned_negation", "replaced by negate_unsigned feature gate"); + store.register_removed("negate_unsigned", "cast a signed value instead"); + store.register_removed("raw_pointer_derive", "using derive with raw pointers is ok"); + // Register lint group aliases. + store.register_group_alias("nonstandard_style", "bad_style"); + // This was renamed to `raw_pointer_derive`, which was then removed, + // so it is also considered removed. + store.register_removed("raw_pointer_deriving", "using derive with raw pointers is ok"); + store.register_removed("drop_with_repr_extern", "drop flags have been removed"); + store.register_removed("fat_ptr_transmutes", "was accidentally removed back in 2014"); + store.register_removed("deprecated_attr", "use `deprecated` instead"); + store.register_removed( + "transmute_from_fn_item_types", + "always cast functions before transmuting them", + ); + store.register_removed( + "hr_lifetime_in_assoc_type", + "converted into hard error, see issue #33685 \ + <https://github.com/rust-lang/rust/issues/33685> for more information", + ); + store.register_removed( + "inaccessible_extern_crate", + "converted into hard error, see issue #36886 \ + <https://github.com/rust-lang/rust/issues/36886> for more information", + ); + store.register_removed( + "super_or_self_in_global_path", + "converted into hard error, see issue #36888 \ + <https://github.com/rust-lang/rust/issues/36888> for more information", + ); + store.register_removed( + "overlapping_inherent_impls", + "converted into hard error, see issue #36889 \ + <https://github.com/rust-lang/rust/issues/36889> for more information", + ); + store.register_removed( + "illegal_floating_point_constant_pattern", + "converted into hard error, see issue #36890 \ + <https://github.com/rust-lang/rust/issues/36890> for more information", + ); + store.register_removed( + "illegal_struct_or_enum_constant_pattern", + "converted into hard error, see issue #36891 \ + <https://github.com/rust-lang/rust/issues/36891> for more information", + ); + store.register_removed( + "lifetime_underscore", + "converted into hard error, see issue #36892 \ + <https://github.com/rust-lang/rust/issues/36892> for more information", + ); + store.register_removed( + "extra_requirement_in_impl", + "converted into hard error, see issue #37166 \ + <https://github.com/rust-lang/rust/issues/37166> for more information", + ); + store.register_removed( + "legacy_imports", + "converted into hard error, see issue #38260 \ + <https://github.com/rust-lang/rust/issues/38260> for more information", + ); + store.register_removed( + "coerce_never", + "converted into hard error, see issue #48950 \ + <https://github.com/rust-lang/rust/issues/48950> for more information", + ); + store.register_removed( + "resolve_trait_on_defaulted_unit", + "converted into hard error, see issue #48950 \ + <https://github.com/rust-lang/rust/issues/48950> for more information", + ); + store.register_removed( + "private_no_mangle_fns", + "no longer a warning, `#[no_mangle]` functions always exported", + ); + store.register_removed( + "private_no_mangle_statics", + "no longer a warning, `#[no_mangle]` statics always exported", + ); + store.register_removed("bad_repr", "replaced with a generic attribute input check"); + store.register_removed( + "duplicate_matcher_binding_name", + "converted into hard error, see issue #57742 \ + <https://github.com/rust-lang/rust/issues/57742> for more information", + ); + store.register_removed( + "incoherent_fundamental_impls", + "converted into hard error, see issue #46205 \ + <https://github.com/rust-lang/rust/issues/46205> for more information", + ); + store.register_removed( + "legacy_constructor_visibility", + "converted into hard error, see issue #39207 \ + <https://github.com/rust-lang/rust/issues/39207> for more information", + ); + store.register_removed( + "legacy_directory_ownership", + "converted into hard error, see issue #37872 \ + <https://github.com/rust-lang/rust/issues/37872> for more information", + ); + store.register_removed( + "safe_extern_statics", + "converted into hard error, see issue #36247 \ + <https://github.com/rust-lang/rust/issues/36247> for more information", + ); + store.register_removed( + "parenthesized_params_in_types_and_modules", + "converted into hard error, see issue #42238 \ + <https://github.com/rust-lang/rust/issues/42238> for more information", + ); + store.register_removed( + "duplicate_macro_exports", + "converted into hard error, see issue #35896 \ + <https://github.com/rust-lang/rust/issues/35896> for more information", + ); + store.register_removed( + "nested_impl_trait", + "converted into hard error, see issue #59014 \ + <https://github.com/rust-lang/rust/issues/59014> for more information", + ); + store.register_removed("plugin_as_library", "plugins have been deprecated and retired"); + store.register_removed( + "unsupported_naked_functions", + "converted into hard error, see RFC 2972 \ + <https://github.com/rust-lang/rfcs/blob/master/text/2972-constrained-naked.md> for more information", + ); + store.register_removed( + "mutable_borrow_reservation_conflict", + "now allowed, see issue #59159 \ + <https://github.com/rust-lang/rust/issues/59159> for more information", + ); +} + +fn register_internals(store: &mut LintStore) { + store.register_lints(&LintPassImpl::get_lints()); + store.register_early_pass(|| Box::new(LintPassImpl)); + store.register_lints(&DefaultHashTypes::get_lints()); + store.register_late_pass(|| Box::new(DefaultHashTypes)); + store.register_lints(&QueryStability::get_lints()); + store.register_late_pass(|| Box::new(QueryStability)); + store.register_lints(&ExistingDocKeyword::get_lints()); + store.register_late_pass(|| Box::new(ExistingDocKeyword)); + store.register_lints(&TyTyKind::get_lints()); + store.register_late_pass(|| Box::new(TyTyKind)); + store.register_lints(&Diagnostics::get_lints()); + store.register_late_pass(|| Box::new(Diagnostics)); + store.register_lints(&BadOptAccess::get_lints()); + store.register_late_pass(|| Box::new(BadOptAccess)); + store.register_lints(&PassByValue::get_lints()); + store.register_late_pass(|| Box::new(PassByValue)); + // FIXME(davidtwco): deliberately do not include `UNTRANSLATABLE_DIAGNOSTIC` and + // `DIAGNOSTIC_OUTSIDE_OF_IMPL` here because `-Wrustc::internal` is provided to every crate and + // these lints will trigger all of the time - change this once migration to diagnostic structs + // and translation is completed + store.register_group( + false, + "rustc::internal", + None, + vec![ + LintId::of(DEFAULT_HASH_TYPES), + LintId::of(POTENTIAL_QUERY_INSTABILITY), + LintId::of(USAGE_OF_TY_TYKIND), + LintId::of(PASS_BY_VALUE), + LintId::of(LINT_PASS_IMPL_WITHOUT_MACRO), + LintId::of(USAGE_OF_QUALIFIED_TY), + LintId::of(EXISTING_DOC_KEYWORD), + LintId::of(BAD_OPT_ACCESS), + ], + ); +} + +#[cfg(test)] +mod tests; |