1.48.0.txt (17216B)
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 meta-variable-misuse allow possible meta-variable misuse at macro definition 22 missing-copy-implementations allow detects potentially-forgotten implementations of `Copy` 23 missing-crate-level-docs allow detects crates with no crate-level documentation 24 missing-debug-implementations allow detects missing implementations of Debug 25 missing-docs allow detects missing documentation for public members 26 missing-doc-code-examples allow detects publicly-exported items without code samples in their documentation 27 non-ascii-idents allow detects non-ASCII identifiers 28 pointer-structural-match allow pointers are not structural-match 29 private-doc-tests allow detects code samples in docs of private items not documented by rustdoc 30 single-use-lifetimes allow detects lifetime parameters that are only used once 31 trivial-casts allow detects trivial casts which could be removed 32 trivial-numeric-casts allow detects trivial casts of numeric types which could be removed 33 unaligned-references allow detects unaligned references to fields of packed structs 34 unreachable-pub allow `pub` items not reachable from crate root 35 unsafe-code allow usage of `unsafe` code 36 unsafe-op-in-unsafe-fn allow unsafe operations in unsafe functions without an explicit unsafe block are deprecated 37 unstable-features allow enabling unstable features (deprecated. do not use) 38 unused-crate-dependencies allow crate dependencies that are never used 39 unused-extern-crates allow extern crates that are never used 40 unused-import-braces allow unnecessary braces around an imported item 41 unused-lifetimes allow detects lifetime parameters that are never used 42 unused-qualifications allow detects unnecessarily qualified names 43 unused-results allow unused result of an expression in a statement 44 variant-size-differences allow detects enums with widely varying variant sizes 45 array-into-iter warn detects calling `into_iter` on arrays 46 asm-sub-register warn using only a subset of a register for inline asm inputs 47 bare-trait-objects warn suggest using `dyn Trait` for trait objects 48 bindings-with-variant-name warn detects pattern bindings with the same name as one of the matched variants 49 broken-intra-doc-links warn failures in resolving intra-doc link targets 50 cenum-impl-drop-cast warn a C-like enum implementing Drop is cast 51 clashing-extern-declarations warn detects when an extern fn has been declared with the same name but different types 52 coherence-leak-check warn distinct impls distinguished only by the leak-check code 53 confusable-idents warn detects visually confusable pairs between identifiers 54 const-evaluatable-unchecked warn detects a generic constant is used in a type without a emitting a warning 55 const-item-mutation warn detects attempts to mutate a `const` item 56 dead-code warn detect unused, unexported items 57 deprecated warn detects use of deprecated items 58 ellipsis-inclusive-range-patterns warn `...` range patterns are deprecated 59 exported-private-dependencies warn public interface leaks type from a private dependency 60 illegal-floating-point-literal-pattern warn floating-point literals cannot be used in patterns 61 improper-ctypes warn proper use of libc types in foreign modules 62 improper-ctypes-definitions warn proper use of libc types in foreign item definitions 63 incomplete-features warn incomplete features that may function improperly in some or all cases 64 indirect-structural-match warn constant used in pattern contains value of non-structural-match type in a field or a variant 65 inline-no-sanitize warn detects incompatible use of `#[inline(always)]` and `#[no_sanitize(...)]` 66 invalid-codeblock-attributes warn codeblock attribute looks a lot like a known one 67 invalid-value warn an invalid value is being created (such as a NULL reference) 68 irrefutable-let-patterns warn detects irrefutable patterns in if-let and while-let statements 69 late-bound-lifetime-arguments warn detects generic lifetime arguments in path segments with late bound lifetime parameters 70 mixed-script-confusables warn detects Unicode scripts whose mixed script confusables codepoints are solely used 71 mutable-borrow-reservation-conflict warn reservation of a two-phased borrow conflicts with other shared borrows 72 nontrivial-structural-match warn constant used in pattern of non-structural-match type and the constant's initializer expression contains values of non-structural-match types 73 non-camel-case-types warn types, variants, traits and type parameters should have camel case names 74 non-shorthand-field-patterns warn using `Struct { x: x }` instead of `Struct { x }` in a pattern 75 non-snake-case warn variables, methods, functions, lifetime parameters and modules should have snake case names 76 non-upper-case-globals warn static constants should have uppercase identifiers 77 no-mangle-generic-items warn generic items must be mangled 78 overlapping-patterns warn detects overlapping patterns 79 path-statements warn path statements with no effect 80 private-in-public warn detect private items in public interfaces not caught by the old implementation 81 proc-macro-derive-resolution-fallback warn detects proc macro derives using inaccessible names from parent modules 82 redundant-semicolons warn detects unnecessary trailing semicolons 83 renamed-and-removed-lints warn lints that have been renamed or removed 84 safe-packed-borrows warn safe borrows of fields of packed structs were erroneously allowed 85 stable-features warn stable features found in `#[feature]` directive 86 trivial-bounds warn these bounds don't depend on an type parameters 87 type-alias-bounds warn bounds in type aliases are not enforced 88 tyvar-behind-raw-pointer warn raw pointer to an inference variable 89 uncommon-codepoints warn detects uncommon Unicode codepoints in identifiers 90 unconditional-recursion warn functions that cannot return without calling themselves 91 unknown-lints warn unrecognized lint attribute 92 unnameable-test-items warn detects an item that cannot be named being marked as `#[test_case]` 93 unreachable-code warn detects unreachable code paths 94 unreachable-patterns warn detects unreachable patterns 95 unstable-name-collisions warn detects name collision with an existing but unstable method 96 unused-allocation warn detects unnecessary allocations that can be eliminated 97 unused-assignments warn detect assignments that will never be read 98 unused-attributes warn detects attributes that were not used by the compiler 99 unused-braces warn unnecessary braces around an expression 100 unused-comparisons warn comparisons made useless by limits of the types involved 101 unused-doc-comments warn detects doc comments that aren't used by rustdoc 102 unused-features warn unused features found in crate-level `#[feature]` directives 103 unused-imports warn imports that are never used 104 unused-labels warn detects labels that are never used 105 unused-macros warn detects macros that were not used 106 unused-must-use warn unused result of a type flagged as `#[must_use]` 107 unused-mut warn detect mut variables which don't need to be mutable 108 unused-parens warn `if`, `match`, `while` and `return` do not need parentheses 109 unused-unsafe warn unnecessary use of an `unsafe` block 110 unused-variables warn detect variables which are not used in any way 111 warnings warn mass-change the level for lints which produce warnings 112 where-clauses-object-safety warn checks the object safety of where clauses 113 while-true warn suggest using `loop { }` instead of `while true { }` 114 ambiguous-associated-items deny ambiguous associated items 115 arithmetic-overflow deny arithmetic operation overflows 116 conflicting-repr-hints deny conflicts between `#[repr(..)]` hints that were previously accepted and used in practice 117 const-err deny constant evaluation detected erroneous expression 118 ill-formed-attribute-input deny ill-formed attribute inputs that were previously accepted and used in practice 119 incomplete-include deny trailing content in included file 120 invalid-type-param-default deny type parameter default erroneously allowed in invalid location 121 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 122 missing-fragment-specifier deny detects missing fragment specifiers in unused `macro_rules!` patterns 123 mutable-transmutes deny mutating transmuted &mut T from &T may cause undefined behavior 124 no-mangle-const-items deny const items will not have their symbols exported 125 order-dependent-trait-objects deny trait-object types were treated as different depending on marker-trait order 126 overflowing-literals deny literal out of range for its type 127 patterns-in-fns-without-body deny patterns in functions without body were erroneously allowed 128 pub-use-of-private-extern-crate deny detect public re-exports of private extern crates 129 soft-unstable deny a feature gate that doesn't break dependent crates 130 unconditional-panic deny operation will cause a panic at runtime 131 unknown-crate-types deny unknown crate type found in `#[crate_type]` directive 132 133 134 Lint groups provided by rustc: 135 136 name sub-lints 137 ---- --------- 138 warnings all lints that are set to issue warnings 139 future-incompatible keyword-idents, anonymous-parameters, illegal-floating-point-literal-pattern, private-in-public, pub-use-of-private-extern-crate, invalid-type-param-default, safe-packed-borrows, patterns-in-fns-without-body, late-bound-lifetime-arguments, order-dependent-trait-objects, coherence-leak-check, tyvar-behind-raw-pointer, absolute-paths-not-starting-with-crate, unstable-name-collisions, where-clauses-object-safety, proc-macro-derive-resolution-fallback, macro-expanded-macro-exports-accessed-by-absolute-paths, ill-formed-attribute-input, conflicting-repr-hints, ambiguous-associated-items, mutable-borrow-reservation-conflict, indirect-structural-match, pointer-structural-match, nontrivial-structural-match, soft-unstable, cenum-impl-drop-cast, const-evaluatable-unchecked, missing-fragment-specifier, array-into-iter 140 nonstandard-style non-camel-case-types, non-snake-case, non-upper-case-globals 141 rust-2018-compatibility keyword-idents, anonymous-parameters, tyvar-behind-raw-pointer, absolute-paths-not-starting-with-crate 142 rust-2018-idioms bare-trait-objects, unused-extern-crates, ellipsis-inclusive-range-patterns, elided-lifetimes-in-paths, explicit-outlives-requirements 143 rustdoc broken-intra-doc-links, private-intra-doc-links, invalid-codeblock-attributes, missing-doc-code-examples, private-doc-tests 144 unused unused-imports, unused-variables, unused-assignments, dead-code, unused-mut, unreachable-code, unreachable-patterns, overlapping-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, unused-braces, redundant-semicolons 145 146 147 Compiler plugins can provide additional lints and lint groups. To see a listing of these, re-run `rustc -W help` with a crate filename.