1.37.0.txt (14078B)
1 2 Available lint options: 3 -W <foo> Warn about <foo> 4 -A <foo> Allow <foo> 5 -D <foo> Deny <foo> 6 -F <foo> Forbid <foo> (deny <foo> and all attempts to override) 7 8 9 Lint checks provided by rustc: 10 11 name default meaning 12 ---- ------- ------- 13 absolute-paths-not-starting-with-crate allow fully qualified paths that start with a module name instead of `crate`, `self`, or an extern crate name 14 anonymous-parameters allow detects anonymous parameters 15 box-pointers allow use of owned (Box type) heap memory 16 deprecated-in-future allow detects use of items that will be deprecated in a future version 17 elided-lifetimes-in-paths allow hidden lifetime parameters in types are deprecated 18 explicit-outlives-requirements allow outlives requirements can be inferred 19 keyword-idents allow detects edition keywords being used as an identifier 20 macro-use-extern-crate allow the `#[macro_use]` attribute is now deprecated in favor of using macros via the module system 21 missing-copy-implementations allow detects potentially-forgotten implementations of `Copy` 22 missing-debug-implementations allow detects missing implementations of fmt::Debug 23 missing-docs allow detects missing documentation for public members 24 missing-doc-code-examples allow detects publicly-exported items without code samples in their documentation 25 private-doc-tests allow detects code samples in docs of private items not documented by rustdoc 26 single-use-lifetimes allow detects lifetime parameters that are only used once 27 trivial-casts allow detects trivial casts which could be removed 28 trivial-numeric-casts allow detects trivial casts of numeric types which could be removed 29 unreachable-pub allow `pub` items not reachable from crate root 30 unsafe-code allow usage of `unsafe` code 31 unstable-features allow enabling unstable features (deprecated. do not use) 32 unused-extern-crates allow extern crates that are never used 33 unused-import-braces allow unnecessary braces around an imported item 34 unused-labels allow detects labels that are never used 35 unused-lifetimes allow detects lifetime parameters that are never used 36 unused-qualifications allow detects unnecessarily qualified names 37 unused-results allow unused result of an expression in a statement 38 variant-size-differences allow detects enums with widely varying variant sizes 39 bare-trait-objects warn suggest using `dyn Trait` for trait objects 40 dead-code warn detect unused, unexported items 41 deprecated warn detects use of deprecated items 42 ellipsis-inclusive-range-patterns warn `...` range patterns are deprecated 43 exported-private-dependencies warn public interface leaks type from a private dependency 44 illegal-floating-point-literal-pattern warn floating-point literals cannot be used in patterns 45 ill-formed-attribute-input warn ill-formed attribute inputs that were previously accepted and used in practice 46 improper-ctypes warn proper use of libc types in foreign modules 47 intra-doc-link-resolution-failure warn failures in resolving intra-doc link targets 48 irrefutable-let-patterns warn detects irrefutable patterns in if-let and while-let statements 49 late-bound-lifetime-arguments warn detects generic lifetime arguments in path segments with late bound lifetime parameters 50 mutable-borrow-reservation-conflict warn reservation of a two-phased borrow conflicts with other shared borrows 51 nested-impl-trait warn nested occurrence of `impl Trait` type 52 non-camel-case-types warn types, variants, traits and type parameters should have camel case names 53 non-shorthand-field-patterns warn using `Struct { x: x }` instead of `Struct { x }` in a pattern 54 non-snake-case warn variables, methods, functions, lifetime parameters and modules should have snake case names 55 non-upper-case-globals warn static constants should have uppercase identifiers 56 no-mangle-generic-items warn generic items must be mangled 57 path-statements warn path statements with no effect 58 patterns-in-fns-without-body warn patterns in functions without body were erroneously allowed 59 plugin-as-library warn compiler plugin used as ordinary library in non-plugin crate 60 private-in-public warn detect private items in public interfaces not caught by the old implementation 61 proc-macro-derive-resolution-fallback warn detects proc macro derives using inaccessible names from parent modules 62 renamed-and-removed-lints warn lints that have been renamed or removed 63 safe-packed-borrows warn safe borrows of fields of packed structs were was erroneously allowed 64 stable-features warn stable features found in #[feature] directive 65 trivial-bounds warn these bounds don't depend on an type parameters 66 type-alias-bounds warn bounds in type aliases are not enforced 67 tyvar-behind-raw-pointer warn raw pointer to an inference variable 68 unconditional-recursion warn functions that cannot return without calling themselves 69 unions-with-drop-fields warn use of unions that contain fields with possibly non-trivial drop code 70 unknown-lints warn unrecognized lint attribute 71 unnameable-test-items warn detects an item that cannot be named being marked as #[test_case] 72 unreachable-code warn detects unreachable code paths 73 unreachable-patterns warn detects unreachable patterns 74 unstable-name-collisions warn detects name collision with an existing but unstable method 75 unused-allocation warn detects unnecessary allocations that can be eliminated 76 unused-assignments warn detect assignments that will never be read 77 unused-attributes warn detects attributes that were not used by the compiler 78 unused-comparisons warn comparisons made useless by limits of the types involved 79 unused-doc-comments warn detects doc comments that aren't used by rustdoc 80 unused-features warn unused features found in crate-level #[feature] directives 81 unused-imports warn imports that are never used 82 unused-macros warn detects macros that were not used 83 unused-must-use warn unused result of a type flagged as #[must_use] 84 unused-mut warn detect mut variables which don't need to be mutable 85 unused-parens warn `if`, `match`, `while` and `return` do not need parentheses 86 unused-unsafe warn unnecessary use of an `unsafe` block 87 unused-variables warn detect variables which are not used in any way 88 warnings warn mass-change the level for lints which produce warnings 89 where-clauses-object-safety warn checks the object safety of where clauses 90 while-true warn suggest using `loop { }` instead of `while true { }` 91 ambiguous-associated-items deny ambiguous associated items 92 const-err deny constant evaluation detected erroneous expression 93 duplicate-macro-exports deny detects duplicate macro exports 94 exceeding-bitshifts deny shift exceeds the type's number of bits 95 invalid-type-param-default deny type parameter default erroneously allowed in invalid location 96 legacy-constructor-visibility deny detects use of struct constructors that would be invisible with new visibility rules 97 legacy-directory-ownership deny non-inline, non-`#[path]` modules (e.g., `mod foo;`) were erroneously allowed in some files not named `mod.rs` 98 macro-expanded-macro-exports-accessed-by-absolute-paths deny macro-expanded `macro_export` macros from the current crate cannot be referred to by absolute paths 99 missing-fragment-specifier deny detects missing fragment specifiers in unused `macro_rules!` patterns 100 mutable-transmutes deny mutating transmuted &mut T from &T may cause undefined behavior 101 no-mangle-const-items deny const items will not have their symbols exported 102 order-dependent-trait-objects deny trait-object types were treated as different depending on marker-trait order 103 overflowing-literals deny literal out of range for its type 104 parenthesized-params-in-types-and-modules deny detects parenthesized generic parameters in type and module names 105 pub-use-of-private-extern-crate deny detect public re-exports of private extern crates 106 safe-extern-statics deny safe access to extern statics was erroneously allowed 107 unknown-crate-types deny unknown crate type found in #[crate_type] directive 108 109 110 Lint groups provided by rustc: 111 112 name sub-lints 113 ---- --------- 114 warnings all lints that are set to issue warnings 115 future-incompatible private-in-public, pub-use-of-private-extern-crate, patterns-in-fns-without-body, duplicate-macro-exports, keyword-idents, safe-extern-statics, invalid-type-param-default, legacy-directory-ownership, legacy-constructor-visibility, missing-fragment-specifier, illegal-floating-point-literal-pattern, anonymous-parameters, parenthesized-params-in-types-and-modules, late-bound-lifetime-arguments, safe-packed-borrows, order-dependent-trait-objects, tyvar-behind-raw-pointer, unstable-name-collisions, absolute-paths-not-starting-with-crate, where-clauses-object-safety, proc-macro-derive-resolution-fallback, macro-expanded-macro-exports-accessed-by-absolute-paths, ill-formed-attribute-input, ambiguous-associated-items, nested-impl-trait, mutable-borrow-reservation-conflict 116 nonstandard-style non-camel-case-types, non-snake-case, non-upper-case-globals 117 rust-2018-compatibility duplicate-macro-exports, keyword-idents, anonymous-parameters, tyvar-behind-raw-pointer, absolute-paths-not-starting-with-crate 118 rust-2018-idioms bare-trait-objects, unused-extern-crates, ellipsis-inclusive-range-patterns, elided-lifetimes-in-paths, explicit-outlives-requirements 119 rustdoc intra-doc-link-resolution-failure, missing-doc-code-examples, private-doc-tests 120 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-allocation, unused-doc-comments, unused-extern-crates, unused-features, unused-labels, unused-parens 121 122 123 Compiler plugins can provide additional lints and lint groups. To see a listing of these, re-run `rustc -W help` with a crate filename.