1.29.0.txt (11831B)
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 async-idents allow detects `async` being used as an identifier 16 bare-trait-objects allow suggest using `dyn Trait` for trait objects 17 box-pointers allow use of owned (Box type) heap memory 18 elided-lifetimes-in-paths allow hidden lifetime parameters in types are deprecated 19 ellipsis-inclusive-range-patterns allow `...` range patterns are deprecated 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 question-mark-macro-sep allow detects the use of `?` as a macro separator 25 single-use-lifetimes allow detects lifetime parameters that are only used once 26 trivial-casts allow detects trivial casts which could be removed 27 trivial-numeric-casts allow detects trivial casts of numeric types which could be removed 28 unreachable-pub allow `pub` items not reachable from crate root 29 unsafe-code allow usage of `unsafe` code 30 unstable-features allow enabling unstable features (deprecated. do not use) 31 unused-extern-crates allow extern crates that are never used 32 unused-import-braces allow unnecessary braces around an imported item 33 unused-labels allow detects labels that are never used 34 unused-lifetimes allow detects lifetime parameters that are never used 35 unused-qualifications allow detects unnecessarily qualified names 36 unused-results allow unused result of an expression in a statement 37 variant-size-differences allow detects enums with widely varying variant sizes 38 dead-code warn detect unused, unexported items 39 deprecated warn detects use of deprecated items 40 duplicate-associated-type-bindings warn warns about duplicate associated type bindings in generics 41 illegal-floating-point-literal-pattern warn floating-point literals cannot be used in patterns 42 improper-ctypes warn proper use of libc types in foreign modules 43 intra-doc-link-resolution-failure warn warn about documentation intra links resolution failure 44 late-bound-lifetime-arguments warn detects generic lifetime arguments in path segments with late bound lifetime parameters 45 non-camel-case-types warn types, variants, traits and type parameters should have camel case names 46 non-shorthand-field-patterns warn using `Struct { x: x }` instead of `Struct { x }` in a pattern 47 non-snake-case warn variables, methods, functions, lifetime parameters and modules should have snake case names 48 non-upper-case-globals warn static constants should have uppercase identifiers 49 no-mangle-generic-items warn generic items must be mangled 50 overflowing-literals warn literal out of range for its type 51 path-statements warn path statements with no effect 52 patterns-in-fns-without-body warn patterns in functions without body were erroneously allowed 53 plugin-as-library warn compiler plugin used as ordinary library in non-plugin crate 54 private-in-public warn detect private items in public interfaces not caught by the old implementation 55 private-no-mangle-fns warn functions marked #[no_mangle] should be exported 56 private-no-mangle-statics warn statics marked #[no_mangle] should be exported 57 proc-macro-derive-resolution-fallback warn detects proc macro derives using inaccessible names from parent modules 58 renamed-and-removed-lints warn lints that have been renamed or removed 59 safe-packed-borrows warn safe borrows of fields of packed structs were was erroneously allowed 60 stable-features warn stable features found in #[feature] directive 61 trivial-bounds warn these bounds don't depend on an type parameters 62 type-alias-bounds warn bounds in type aliases are not enforced 63 tyvar-behind-raw-pointer warn raw pointer to an inference variable 64 unconditional-recursion warn functions that cannot return without calling themselves 65 unions-with-drop-fields warn use of unions that contain fields with possibly non-trivial drop code 66 unknown-lints warn unrecognized lint attribute 67 unnameable-test-functions warn detects an function that cannot be named being marked as #[test] 68 unreachable-code warn detects unreachable code paths 69 unreachable-patterns warn detects unreachable patterns 70 unstable-name-collisions warn detects name collision with an existing but unstable method 71 unused-allocation warn detects unnecessary allocations that can be eliminated 72 unused-assignments warn detect assignments that will never be read 73 unused-attributes warn detects attributes that were not used by the compiler 74 unused-comparisons warn comparisons made useless by limits of the types involved 75 unused-doc-comments warn detects doc comments that aren't used by rustdoc 76 unused-features warn unused or unknown features found in crate-level #[feature] directives 77 unused-imports warn imports that are never used 78 unused-macros warn detects macros that were not used 79 unused-must-use warn unused result of a type flagged as #[must_use] 80 unused-mut warn detect mut variables which don't need to be mutable 81 unused-parens warn `if`, `match`, `while` and `return` do not need parentheses 82 unused-unsafe warn unnecessary use of an `unsafe` block 83 unused-variables warn detect variables which are not used in any way 84 warnings warn mass-change the level for lints which produce warnings 85 where-clauses-object-safety warn checks the object safety of where clauses 86 while-true warn suggest using `loop { }` instead of `while true { }` 87 const-err deny constant evaluation detected erroneous expression 88 duplicate-macro-exports deny detects duplicate macro exports 89 exceeding-bitshifts deny shift exceeds the type's number of bits 90 incoherent-fundamental-impls deny potentially-conflicting impls were erroneously allowed 91 invalid-type-param-default deny type parameter default erroneously allowed in invalid location 92 irrefutable-let-patterns deny detects irrefutable patterns in if-let and while-let statements 93 legacy-constructor-visibility deny detects use of struct constructors that would be invisible with new visibility rules 94 legacy-directory-ownership deny non-inline, non-`#[path]` modules (e.g. `mod foo;`) were erroneously allowed in some files not named `mod.rs` 95 missing-fragment-specifier deny detects missing fragment specifiers in unused `macro_rules!` patterns 96 mutable-transmutes deny mutating transmuted &mut T from &T may cause undefined behavior 97 no-mangle-const-items deny const items will not have their symbols exported 98 parenthesized-params-in-types-and-modules deny detects parenthesized generic parameters in type and module names 99 pub-use-of-private-extern-crate deny detect public re-exports of private extern crates 100 safe-extern-statics deny safe access to extern statics was erroneously allowed 101 unknown-crate-types deny unknown crate type found in #[crate_type] directive 102 103 104 Lint groups provided by rustc: 105 106 name sub-lints 107 ---- --------- 108 warnings all lints that are set to issue warnings 109 bad-style non-camel-case-types, non-snake-case, non-upper-case-globals 110 future-incompatible private-in-public, pub-use-of-private-extern-crate, patterns-in-fns-without-body, duplicate-macro-exports, async-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, incoherent-fundamental-impls, tyvar-behind-raw-pointer, unstable-name-collisions, absolute-paths-not-starting-with-crate, where-clauses-object-safety, duplicate-associated-type-bindings, proc-macro-derive-resolution-fallback, question-mark-macro-sep 111 nonstandard-style non-camel-case-types, non-snake-case, non-upper-case-globals 112 rust-2018-compatibility duplicate-macro-exports, async-idents, tyvar-behind-raw-pointer, absolute-paths-not-starting-with-crate, question-mark-macro-sep 113 rust-2018-idioms bare-trait-objects, unreachable-pub, unused-extern-crates, macro-use-extern-crate, elided-lifetimes-in-paths, ellipsis-inclusive-range-patterns 114 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 115 116 117 Compiler plugins can provide additional lints and lint groups. To see a listing of these, re-run `rustc -W help` with a crate filename.