src/librustc_lint/lib.rs

   1 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 //! Lints in the Rust compiler.
  12 //!
  13 //! This currently only contains the definitions and implementations
  14 //! of most of the lints that `rustc` supports directly, it does not
  15 //! contain the infrastructure for defining/registering lints. That is
  16 //! available in `rustc::lint` and `rustc_plugin` respectively.
  17 //!
  18 //! # Note
  19 //!
  20 //! This API is completely unstable and subject to change.
  21
  22 #![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
  23       html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
  24       html_root_url = "https://doc.rust-lang.org/nightly/")]
  25
  26 #![cfg_attr(test, feature(test))]
  27 #![feature(box_patterns)]
  28 #![feature(box_syntax)]
  29 #![feature(macro_vis_matcher)]
  30 #![feature(quote)]
  31 #![feature(rustc_diagnostic_macros)]
  32 #![feature(macro_at_most_once_rep)]
  33
  34 extern crate syntax;
  35 #[macro_use]
  36 extern crate rustc;
  37 #[macro_use]
  38 extern crate log;
  39 extern crate rustc_mir;
  40 extern crate rustc_target;
  41 extern crate syntax_pos;
  42
  43 use rustc::lint;
  44 use rustc::lint::{LateContext, LateLintPass, LintPass, LintArray};
  45 use rustc::lint::builtin::{BARE_TRAIT_OBJECTS, ABSOLUTE_PATHS_NOT_STARTING_WITH_CRATE};
  46 use rustc::lint::builtin::MACRO_USE_EXTERN_CRATE;
  47 use rustc::session;
  48 use rustc::util;
  49 use rustc::hir;
  50
  51 use syntax::ast;
  52 use syntax_pos::Span;
  53
  54 use session::Session;
  55 use syntax::edition::Edition;
  56 use lint::LintId;
  57 use lint::FutureIncompatibleInfo;
  58
  59 mod bad_style;
  60 pub mod builtin;
  61 mod types;
  62 mod unused;
  63
  64 use bad_style::*;
  65 use builtin::*;
  66 use types::*;
  67 use unused::*;
  68
  69 /// Useful for other parts of the compiler.
  70 pub use builtin::SoftLints;
  71
  72 /// Tell the `LintStore` about all the built-in lints (the ones
  73 /// defined in this crate and the ones defined in
  74 /// `rustc::lint::builtin`).
  75 pub fn register_builtins(store: &mut lint::LintStore, sess: Option<&Session>) {
  76     macro_rules! add_early_builtin {
  77         ($sess:ident, $($name:ident),*,) => (
  78             {$(
  79                 store.register_early_pass($sess, false, box $name);
  80                 )*}
  81             )
  82     }
  83
  84     macro_rules! add_early_builtin_with_new {
  85         ($sess:ident, $($name:ident),*,) => (
  86             {$(
  87                 store.register_early_pass($sess, false, box $name::new());
  88                 )*}
  89             )
  90     }
  91
  92     macro_rules! add_lint_group {
  93         ($sess:ident, $name:expr, $($lint:ident),*) => (
  94             store.register_group($sess, false, $name, vec![$(LintId::of($lint)),*]);
  95             )
  96     }
  97
  98     add_early_builtin!(sess,
  99                        UnusedParens,
 100                        UnusedImportBraces,
 101                        AnonymousParameters,
 102                        UnusedDocComment,
 103                        BadRepr,
 104                        EllipsisInclusiveRangePatterns,
 105                        );
 106
 107     add_early_builtin_with_new!(sess,
 108                                 DeprecatedAttr,
 109                                 );
 110
 111     late_lint_methods!(declare_combined_late_lint_pass, [BuiltinCombinedLateLintPass, [
 112         HardwiredLints: HardwiredLints,
 113         WhileTrue: WhileTrue,
 114         ImproperCTypes: ImproperCTypes,
 115         VariantSizeDifferences: VariantSizeDifferences,
 116         BoxPointers: BoxPointers,
 117         UnusedAttributes: UnusedAttributes,
 118         PathStatements: PathStatements,
 119         UnusedResults: UnusedResults,
 120         NonCamelCaseTypes: NonCamelCaseTypes,
 121         NonSnakeCase: NonSnakeCase,
 122         NonUpperCaseGlobals: NonUpperCaseGlobals,
 123         NonShorthandFieldPatterns: NonShorthandFieldPatterns,
 124         UnsafeCode: UnsafeCode,
 125         UnusedAllocation: UnusedAllocation,
 126         MissingCopyImplementations: MissingCopyImplementations,
 127         UnstableFeatures: UnstableFeatures,
 128         UnconditionalRecursion: UnconditionalRecursion,
 129         InvalidNoMangleItems: InvalidNoMangleItems,
 130         PluginAsLibrary: PluginAsLibrary,
 131         MutableTransmutes: MutableTransmutes,
 132         UnionsWithDropFields: UnionsWithDropFields,
 133         UnreachablePub: UnreachablePub,
 134         UnnameableTestFunctions: UnnameableTestFunctions,
 135         TypeAliasBounds: TypeAliasBounds,
 136         UnusedBrokenConst: UnusedBrokenConst,
 137         TrivialConstraints: TrivialConstraints,
 138         TypeLimits: TypeLimits::new(),
 139         MissingDoc: MissingDoc::new(),
 140         MissingDebugImplementations: MissingDebugImplementations::new(),
 141     ]], ['tcx]);
 142
 143     store.register_late_pass(sess, false, box BuiltinCombinedLateLintPass::new());
 144
 145     add_lint_group!(sess,
 146                     "bad_style",
 147                     NON_CAMEL_CASE_TYPES,
 148                     NON_SNAKE_CASE,
 149                     NON_UPPER_CASE_GLOBALS);
 150
 151     add_lint_group!(sess,
 152                     "nonstandard_style",
 153                     NON_CAMEL_CASE_TYPES,
 154                     NON_SNAKE_CASE,
 155                     NON_UPPER_CASE_GLOBALS);
 156
 157     add_lint_group!(sess,
 158                     "unused",
 159                     UNUSED_IMPORTS,
 160                     UNUSED_VARIABLES,
 161                     UNUSED_ASSIGNMENTS,
 162                     DEAD_CODE,
 163                     UNUSED_MUT,
 164                     UNREACHABLE_CODE,
 165                     UNREACHABLE_PATTERNS,
 166                     UNUSED_MUST_USE,
 167                     UNUSED_UNSAFE,
 168                     PATH_STATEMENTS,
 169                     UNUSED_ATTRIBUTES,
 170                     UNUSED_MACROS,
 171                     UNUSED_ALLOCATION,
 172                     UNUSED_DOC_COMMENTS,
 173                     UNUSED_EXTERN_CRATES,
 174                     UNUSED_FEATURES,
 175                     UNUSED_LABELS,
 176                     UNUSED_PARENS);
 177
 178     add_lint_group!(sess,
 179                     "rust_2018_idioms",
 180                     BARE_TRAIT_OBJECTS,
 181                     UNREACHABLE_PUB,
 182                     UNUSED_EXTERN_CRATES,
 183                     MACRO_USE_EXTERN_CRATE,
 184                     ELLIPSIS_INCLUSIVE_RANGE_PATTERNS);
 185
 186     // Guidelines for creating a future incompatibility lint:
 187     //
 188     // - Create a lint defaulting to warn as normal, with ideally the same error
 189     //   message you would normally give
 190     // - Add a suitable reference, typically an RFC or tracking issue. Go ahead
 191     //   and include the full URL, sort items in ascending order of issue numbers.
 192     // - Later, change lint to error
 193     // - Eventually, remove lint
 194     store.register_future_incompatible(sess,
 195                                        vec![
 196         FutureIncompatibleInfo {
 197             id: LintId::of(PRIVATE_IN_PUBLIC),
 198             reference: "issue #34537 <https://github.com/rust-lang/rust/issues/34537>",
 199             edition: None,
 200         },
 201         FutureIncompatibleInfo {
 202             id: LintId::of(PUB_USE_OF_PRIVATE_EXTERN_CRATE),
 203             reference: "issue #34537 <https://github.com/rust-lang/rust/issues/34537>",
 204             edition: None,
 205         },
 206         FutureIncompatibleInfo {
 207             id: LintId::of(PATTERNS_IN_FNS_WITHOUT_BODY),
 208             reference: "issue #35203 <https://github.com/rust-lang/rust/issues/35203>",
 209             edition: None,
 210         },
 211         FutureIncompatibleInfo {
 212             id: LintId::of(DUPLICATE_MACRO_EXPORTS),
 213             reference: "issue #35896 <https://github.com/rust-lang/rust/issues/35896>",
 214             edition: Some(Edition::Edition2018),
 215         },
 216         FutureIncompatibleInfo {
 217             id: LintId::of(SAFE_EXTERN_STATICS),
 218             reference: "issue #36247 <https://github.com/rust-lang/rust/issues/36247>",
 219             edition: None,
 220         },
 221         FutureIncompatibleInfo {
 222             id: LintId::of(INVALID_TYPE_PARAM_DEFAULT),
 223             reference: "issue #36887 <https://github.com/rust-lang/rust/issues/36887>",
 224             edition: None,
 225         },
 226         FutureIncompatibleInfo {
 227             id: LintId::of(LEGACY_DIRECTORY_OWNERSHIP),
 228             reference: "issue #37872 <https://github.com/rust-lang/rust/issues/37872>",
 229             edition: None,
 230         },
 231         FutureIncompatibleInfo {
 232             id: LintId::of(LEGACY_CONSTRUCTOR_VISIBILITY),
 233             reference: "issue #39207 <https://github.com/rust-lang/rust/issues/39207>",
 234             edition: None,
 235         },
 236         FutureIncompatibleInfo {
 237             id: LintId::of(MISSING_FRAGMENT_SPECIFIER),
 238             reference: "issue #40107 <https://github.com/rust-lang/rust/issues/40107>",
 239             edition: None,
 240         },
 241         FutureIncompatibleInfo {
 242             id: LintId::of(ILLEGAL_FLOATING_POINT_LITERAL_PATTERN),
 243             reference: "issue #41620 <https://github.com/rust-lang/rust/issues/41620>",
 244             edition: None,
 245         },
 246         FutureIncompatibleInfo {
 247             id: LintId::of(ANONYMOUS_PARAMETERS),
 248             reference: "issue #41686 <https://github.com/rust-lang/rust/issues/41686>",
 249             edition: None,
 250         },
 251         FutureIncompatibleInfo {
 252             id: LintId::of(PARENTHESIZED_PARAMS_IN_TYPES_AND_MODULES),
 253             reference: "issue #42238 <https://github.com/rust-lang/rust/issues/42238>",
 254             edition: None,
 255         },
 256         FutureIncompatibleInfo {
 257             id: LintId::of(LATE_BOUND_LIFETIME_ARGUMENTS),
 258             reference: "issue #42868 <https://github.com/rust-lang/rust/issues/42868>",
 259             edition: None,
 260         },
 261         FutureIncompatibleInfo {
 262             id: LintId::of(SAFE_PACKED_BORROWS),
 263             reference: "issue #46043 <https://github.com/rust-lang/rust/issues/46043>",
 264             edition: None,
 265         },
 266         FutureIncompatibleInfo {
 267             id: LintId::of(INCOHERENT_FUNDAMENTAL_IMPLS),
 268             reference: "issue #46205 <https://github.com/rust-lang/rust/issues/46205>",
 269             edition: None,
 270         },
 271         FutureIncompatibleInfo {
 272             id: LintId::of(TYVAR_BEHIND_RAW_POINTER),
 273             reference: "issue #46906 <https://github.com/rust-lang/rust/issues/46906>",
 274             edition: Some(Edition::Edition2018),
 275         },
 276         FutureIncompatibleInfo {
 277             id: LintId::of(UNSTABLE_NAME_COLLISIONS),
 278             reference: "issue #48919 <https://github.com/rust-lang/rust/issues/48919>",
 279             edition: None,
 280             // Note: this item represents future incompatibility of all unstable functions in the
 281             //       standard library, and thus should never be removed or changed to an error.
 282         },
 283         FutureIncompatibleInfo {
 284             id: LintId::of(ABSOLUTE_PATHS_NOT_STARTING_WITH_CRATE),
 285             reference: "issue TBD",
 286             edition: Some(Edition::Edition2018),
 287         },
 288         FutureIncompatibleInfo {
 289             id: LintId::of(WHERE_CLAUSES_OBJECT_SAFETY),
 290             reference: "issue #51443 <https://github.com/rust-lang/rust/issues/51443>",
 291             edition: None,
 292         },
 293         FutureIncompatibleInfo {
 294             id: LintId::of(DUPLICATE_ASSOCIATED_TYPE_BINDINGS),
 295             reference: "issue #50589 <https://github.com/rust-lang/rust/issues/50589>",
 296             edition: None,
 297         },
 298         FutureIncompatibleInfo {
 299             id: LintId::of(PROC_MACRO_DERIVE_RESOLUTION_FALLBACK),
 300             reference: "issue #50504 <https://github.com/rust-lang/rust/issues/50504>",
 301             edition: None,
 302         },
 303         ]);
 304
 305     // Register renamed and removed lints
 306     store.register_renamed("single_use_lifetime", "single_use_lifetimes");
 307     store.register_renamed("elided_lifetime_in_path", "elided_lifetimes_in_paths");
 308     store.register_renamed("bare_trait_object", "bare_trait_objects");
 309     store.register_renamed("unstable_name_collision", "unstable_name_collisions");
 310     store.register_renamed("unused_doc_comment", "unused_doc_comments");
 311     store.register_renamed("unknown_features", "unused_features");
 312     store.register_removed("unsigned_negation", "replaced by negate_unsigned feature gate");
 313     store.register_removed("negate_unsigned", "cast a signed value instead");
 314     store.register_removed("raw_pointer_derive", "using derive with raw pointers is ok");
 315     // This was renamed to raw_pointer_derive, which was then removed,
 316     // so it is also considered removed
 317     store.register_removed("raw_pointer_deriving", "using derive with raw pointers is ok");
 318     store.register_removed("drop_with_repr_extern", "drop flags have been removed");
 319     store.register_removed("fat_ptr_transmutes", "was accidentally removed back in 2014");
 320     store.register_removed("deprecated_attr", "use `deprecated` instead");
 321     store.register_removed("transmute_from_fn_item_types",
 322         "always cast functions before transmuting them");
 323     store.register_removed("hr_lifetime_in_assoc_type",
 324         "converted into hard error, see https://github.com/rust-lang/rust/issues/33685");
 325     store.register_removed("inaccessible_extern_crate",
 326         "converted into hard error, see https://github.com/rust-lang/rust/issues/36886");
 327     store.register_removed("super_or_self_in_global_path",
 328         "converted into hard error, see https://github.com/rust-lang/rust/issues/36888");
 329     store.register_removed("overlapping_inherent_impls",
 330         "converted into hard error, see https://github.com/rust-lang/rust/issues/36889");
 331     store.register_removed("illegal_floating_point_constant_pattern",
 332         "converted into hard error, see https://github.com/rust-lang/rust/issues/36890");
 333     store.register_removed("illegal_struct_or_enum_constant_pattern",
 334         "converted into hard error, see https://github.com/rust-lang/rust/issues/36891");
 335     store.register_removed("lifetime_underscore",
 336         "converted into hard error, see https://github.com/rust-lang/rust/issues/36892");
 337     store.register_removed("extra_requirement_in_impl",
 338         "converted into hard error, see https://github.com/rust-lang/rust/issues/37166");
 339     store.register_removed("legacy_imports",
 340         "converted into hard error, see https://github.com/rust-lang/rust/issues/38260");
 341     store.register_removed("coerce_never",
 342         "converted into hard error, see https://github.com/rust-lang/rust/issues/48950");
 343     store.register_removed("resolve_trait_on_defaulted_unit",
 344         "converted into hard error, see https://github.com/rust-lang/rust/issues/48950");
 345 }