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