Available lint options:
-W <foo> Warn about <foo>
-A <foo> Allow <foo>
-D <foo> Deny <foo>
-F <foo> Forbid <foo> (deny <foo> and all attempts to override)
Lint checks provided by rustc:
name default meaning
---- ------- -------
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
anonymous-parameters allow detects anonymous parameters
box-pointers allow use of owned (Box type) heap memory
confusable-idents allow detects visually confusable pairs between identifiers
deprecated-in-future allow detects use of items that will be deprecated in a future version
elided-lifetimes-in-paths allow hidden lifetime parameters in types are deprecated
explicit-outlives-requirements allow outlives requirements can be inferred
indirect-structural-match allow pattern with const indirectly referencing non-structural-match type
keyword-idents allow detects edition keywords being used as an identifier
macro-use-extern-crate allow the `#[macro_use]` attribute is now deprecated in favor of using macros via the module system
meta-variable-misuse allow possible meta-variable misuse at macro definition
missing-copy-implementations allow detects potentially-forgotten implementations of `Copy`
missing-crate-level-docs allow detects crates with no crate-level documentation
missing-debug-implementations allow detects missing implementations of Debug
missing-docs allow detects missing documentation for public members
missing-doc-code-examples allow detects publicly-exported items without code samples in their documentation
non-ascii-idents allow detects non-ASCII identifiers
private-doc-tests allow detects code samples in docs of private items not documented by rustdoc
single-use-lifetimes allow detects lifetime parameters that are only used once
trivial-casts allow detects trivial casts which could be removed
trivial-numeric-casts allow detects trivial casts of numeric types which could be removed
unaligned-references allow detects unaligned references to fields of packed structs
unreachable-pub allow `pub` items not reachable from crate root
unsafe-code allow usage of `unsafe` code
unsafe-op-in-unsafe-fn allow unsafe operations in unsafe functions without an explicit unsafe block are deprecated
unstable-features allow enabling unstable features (deprecated. do not use)
unused-crate-dependencies allow crate dependencies that are never used
unused-extern-crates allow extern crates that are never used
unused-import-braces allow unnecessary braces around an imported item
unused-lifetimes allow detects lifetime parameters that are never used
unused-qualifications allow detects unnecessarily qualified names
unused-results allow unused result of an expression in a statement
variant-size-differences allow detects enums with widely varying variant sizes
array-into-iter warn detects calling `into_iter` on arrays
asm-sub-register warn using only a subset of a register for inline asm inputs
bare-trait-objects warn suggest using `dyn Trait` for trait objects
bindings-with-variant-name warn detects pattern bindings with the same name as one of the matched variants
coherence-leak-check warn distinct impls distinguished only by the leak-check code
dead-code warn detect unused, unexported items
deprecated warn detects use of deprecated items
ellipsis-inclusive-range-patterns warn `...` range patterns are deprecated
exported-private-dependencies warn public interface leaks type from a private dependency
illegal-floating-point-literal-pattern warn floating-point literals cannot be used in patterns
improper-ctypes warn proper use of libc types in foreign modules
incomplete-features warn incomplete features that may function improperly in some or all cases
inline-no-sanitize warn detects incompatible use of `#[inline(always)]` and `#[no_sanitize(...)]`
intra-doc-link-resolution-failure warn failures in resolving intra-doc link targets
invalid-codeblock-attribute warn codeblock attribute looks a lot like a known one
invalid-value warn an invalid value is being created (such as a NULL reference)
irrefutable-let-patterns warn detects irrefutable patterns in if-let and while-let statements
late-bound-lifetime-arguments warn detects generic lifetime arguments in path segments with late bound lifetime parameters
mutable-borrow-reservation-conflict warn reservation of a two-phased borrow conflicts with other shared borrows
non-camel-case-types warn types, variants, traits and type parameters should have camel case names
non-shorthand-field-patterns warn using `Struct { x: x }` instead of `Struct { x }` in a pattern
non-snake-case warn variables, methods, functions, lifetime parameters and modules should have snake case names
non-upper-case-globals warn static constants should have uppercase identifiers
no-mangle-generic-items warn generic items must be mangled
overlapping-patterns warn detects overlapping patterns
path-statements warn path statements with no effect
private-in-public warn detect private items in public interfaces not caught by the old implementation
proc-macro-derive-resolution-fallback warn detects proc macro derives using inaccessible names from parent modules
redundant-semicolons warn detects unnecessary trailing semicolons
renamed-and-removed-lints warn lints that have been renamed or removed
safe-packed-borrows warn safe borrows of fields of packed structs were erroneously allowed
stable-features warn stable features found in `#[feature]` directive
trivial-bounds warn these bounds don't depend on an type parameters
type-alias-bounds warn bounds in type aliases are not enforced
tyvar-behind-raw-pointer warn raw pointer to an inference variable
uncommon-codepoints warn detects uncommon Unicode codepoints in identifiers
unconditional-recursion warn functions that cannot return without calling themselves
unknown-lints warn unrecognized lint attribute
unnameable-test-items warn detects an item that cannot be named being marked as `#[test_case]`
unreachable-code warn detects unreachable code paths
unreachable-patterns warn detects unreachable patterns
unstable-name-collisions warn detects name collision with an existing but unstable method
unused-allocation warn detects unnecessary allocations that can be eliminated
unused-assignments warn detect assignments that will never be read
unused-attributes warn detects attributes that were not used by the compiler
unused-braces warn unnecessary braces around an expression
unused-comparisons warn comparisons made useless by limits of the types involved
unused-doc-comments warn detects doc comments that aren't used by rustdoc
unused-features warn unused features found in crate-level `#[feature]` directives
unused-imports warn imports that are never used
unused-labels warn detects labels that are never used
unused-macros warn detects macros that were not used
unused-must-use warn unused result of a type flagged as `#[must_use]`
unused-mut warn detect mut variables which don't need to be mutable
unused-parens warn `if`, `match`, `while` and `return` do not need parentheses
unused-unsafe warn unnecessary use of an `unsafe` block
unused-variables warn detect variables which are not used in any way
warnings warn mass-change the level for lints which produce warnings
where-clauses-object-safety warn checks the object safety of where clauses
while-true warn suggest using `loop { }` instead of `while true { }`
ambiguous-associated-items deny ambiguous associated items
arithmetic-overflow deny arithmetic operation overflows
conflicting-repr-hints deny conflicts between `#[repr(..)]` hints that were previously accepted and used in practice
const-err deny constant evaluation detected erroneous expression
ill-formed-attribute-input deny ill-formed attribute inputs that were previously accepted and used in practice
invalid-type-param-default deny type parameter default erroneously allowed in invalid location
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
missing-fragment-specifier deny detects missing fragment specifiers in unused `macro_rules!` patterns
mutable-transmutes deny mutating transmuted &mut T from &T may cause undefined behavior
no-mangle-const-items deny const items will not have their symbols exported
order-dependent-trait-objects deny trait-object types were treated as different depending on marker-trait order
overflowing-literals deny literal out of range for its type
patterns-in-fns-without-body deny patterns in functions without body were erroneously allowed
pub-use-of-private-extern-crate deny detect public re-exports of private extern crates
soft-unstable deny a feature gate that doesn't break dependent crates
unconditional-panic deny operation will cause a panic at runtime
unknown-crate-types deny unknown crate type found in `#[crate_type]` directive
Lint groups provided by rustc:
name sub-lints
---- ---------
warnings all lints that are set to issue warnings
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, missing-fragment-specifier, 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, soft-unstable, array-into-iter
nonstandard-style non-camel-case-types, non-snake-case, non-upper-case-globals
rust-2018-compatibility keyword-idents, anonymous-parameters, tyvar-behind-raw-pointer, absolute-paths-not-starting-with-crate
rust-2018-idioms bare-trait-objects, unused-extern-crates, ellipsis-inclusive-range-patterns, elided-lifetimes-in-paths, explicit-outlives-requirements
rustdoc intra-doc-link-resolution-failure, invalid-codeblock-attribute, missing-doc-code-examples, private-doc-tests
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
Compiler plugins can provide additional lints and lint groups. To see a listing of these, re-run `rustc -W help` with a crate filename.