Crate rustc_lint

Lints, aka compiler warnings.

A ‘lint’ check is a kind of miscellaneous constraint that a user might want to enforce, but might reasonably want to permit as well, on a module-by-module basis. They contrast with static constraints enforced by other phases of the compiler, which are generally required to hold in order to compile the program at all.

Most lints can be written as LintPass instances. These run after all other analyses. The LintPasses built into rustc are defined within rustc_session::lint::builtin, which has further comments on how to add such a lint. rustc can also load user-defined lint plugins via the plugin mechanism.

Some of rustc’s lints are defined elsewhere in the compiler and work by calling add_lint() on the overall Session object. This works when it happens before the main lint pass, which emits the lints stored by add_lint(). To emit lints after the main lint pass (from codegen, for example) requires more effort. See emit_lint and GatherNodeLevels in context.rs.

Some code also exists in rustc_session::lint, rustc_middle::lint.

Note

This API is completely unstable and subject to change.

Re-exports

pub use builtin::SoftLints;

pub use rustc_session::lint::Level::*;

Modules

array_into_iter 🔒

builtin

Lints in the Rust compiler.

context 🔒

Implementation of lint checking.

early 🔒

Implementation of lint checking.

enum_intrinsics_non_enums 🔒

errors 🔒

expect 🔒

hidden_unicode_codepoints

internal 🔒

Some lints that are only useful in the compiler or crates that use compiler internals, such as Clippy.

late 🔒

Implementation of lint checking.

let_underscore 🔒

levels 🔒

methods 🔒

non_ascii_idents 🔒

non_fmt_panic 🔒

nonstandard_style 🔒

noop_method_call 🔒

pass_by_value 🔒

passes 🔒

redundant_semicolon 🔒

traits 🔒

types 🔒

unused 🔒

Macros

declare_combined_early_lint_pass

declare_combined_early_pass 🔒

declare_combined_late_lint_pass

declare_combined_late_pass 🔒

early_lint_methods

early_lint_passes 🔒

expand_combined_early_lint_pass_method

expand_combined_early_lint_pass_methods

expand_combined_late_lint_pass_method

expand_combined_late_lint_pass_methods

late_lint_methods

late_lint_mod_passes 🔒

late_lint_passes 🔒

pre_expansion_lint_passes 🔒

Structs

BufferedEarlyLint

Lints that are buffered up early on in the Session before the LintLevels is calculated.

BuiltinCombinedEarlyLintPass

BuiltinCombinedLateLintPass

BuiltinCombinedModuleLateLintPass 🔒

BuiltinCombinedPreExpansionLintPass

EarlyContext

Context for lint checking of the AST, after expansion, before lowering to HIR.

FutureIncompatibleInfo

Extra information for a future incompatibility lint.

LateContext

Context for lint checking outside of type inference.

Lint

Specification of a single lint.

LintId

Identifies a lint known to the compiler.

LintStore

Information about the registered lints.

Enums

CheckLintNameResult

FindLintError

Level

Setting for how to handle a lint.

Statics

ARRAY_INTO_ITER

The array_into_iter lint detects calling into_iter on arrays.

Traits

EarlyCheckNode

Early lints work on different nodes - either on the crate root, or on freshly loaded modules. This trait generalizes over those nodes.

EarlyLintPass

LateLintPass

LintContext

LintPass

Functions

check_ast_node

check_crate

Performs lint checking on a crate.

lint_mod 🔒

new_lint_store

provide

register_builtins 🔒

Tell the LintStore about all the built-in lints (the ones defined in this crate and the ones defined in rustc_session::lint::builtin).

register_internals 🔒

unerased_lint_store

Extract the LintStore from the query context. This function exists because we’ve erased LintStore as dyn Any in the context.

Type Definitions

LintArray