lib.rs

// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

//! Lints in the Rust compiler.
//!
//! This currently only contains the definitions and implementations
//! of most of the lints that `rustc` supports directly, it does not
//! contain the infrastructure for defining/registering lints. That is
//! available in `rustc::lint` and `rustc_plugin` respectively.
//!
//! # Note
//!
//! This API is completely unstable and subject to change.

#![crate_name = "rustc_lint"]
#![crate_type = "dylib"]
#![crate_type = "rlib"]
#![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
      html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
      html_root_url = "https://doc.rust-lang.org/nightly/")]
#![deny(warnings)]

#![cfg_attr(test, feature(test))]
#![feature(box_patterns)]
#![feature(box_syntax)]
#![feature(i128_type)]
#![feature(quote)]
#![feature(rustc_diagnostic_macros)]
#![feature(slice_patterns)]

#![cfg_attr(stage0, unstable(feature = "rustc_private", issue = "27812"))]
#![cfg_attr(stage0, feature(rustc_private))]
#![cfg_attr(stage0, feature(staged_api))]

#[macro_use]
extern crate syntax;
#[macro_use]
extern crate rustc;
#[macro_use]
extern crate log;
extern crate rustc_back;
extern crate rustc_const_eval;
extern crate syntax_pos;

pub use rustc::lint;
pub use rustc::middle;
pub use rustc::session;
pub use rustc::util;

use session::Session;
use lint::LintId;
use lint::FutureIncompatibleInfo;

mod bad_style;
mod builtin;
mod types;
mod unused;

use bad_style::*;
use builtin::*;
use types::*;
use unused::*;

/// Tell the `LintStore` about all the built-in lints (the ones
/// defined in this crate and the ones defined in
/// `rustc::lint::builtin`).
pub fn register_builtins(store: &mut lint::LintStore, sess: Option<&Session>) {
    macro_rules! add_builtin {
        ($sess:ident, $($name:ident),*,) => (
            {$(
                store.register_late_pass($sess, false, box $name);
                )*}
            )
    }

    macro_rules! add_early_builtin {
        ($sess:ident, $($name:ident),*,) => (
            {$(
                store.register_early_pass($sess, false, box $name);
                )*}
            )
    }

    macro_rules! add_builtin_with_new {
        ($sess:ident, $($name:ident),*,) => (
            {$(
                store.register_late_pass($sess, false, box $name::new());
                )*}
            )
    }

    macro_rules! add_early_builtin_with_new {
        ($sess:ident, $($name:ident),*,) => (
            {$(
                store.register_early_pass($sess, false, box $name::new());
                )*}
            )
    }

    macro_rules! add_lint_group {
        ($sess:ident, $name:expr, $($lint:ident),*) => (
            store.register_group($sess, false, $name, vec![$(LintId::of($lint)),*]);
            )
    }

    add_early_builtin!(sess,
                       UnusedParens,
                       UnusedImportBraces,
                       AnonymousParameters,
                       IllegalFloatLiteralPattern,
                       );

    add_early_builtin_with_new!(sess,
                                DeprecatedAttr,
                                );

    add_builtin!(sess,
                 HardwiredLints,
                 WhileTrue,
                 ImproperCTypes,
                 VariantSizeDifferences,
                 BoxPointers,
                 UnusedAttributes,
                 PathStatements,
                 UnusedResults,
                 NonCamelCaseTypes,
                 NonSnakeCase,
                 NonUpperCaseGlobals,
                 NonShorthandFieldPatterns,
                 UnusedUnsafe,
                 UnsafeCode,
                 UnusedMut,
                 UnusedAllocation,
                 MissingCopyImplementations,
                 UnstableFeatures,
                 UnconditionalRecursion,
                 InvalidNoMangleItems,
                 PluginAsLibrary,
                 MutableTransmutes,
                 UnionsWithDropFields,
                 );

    add_builtin_with_new!(sess,
                          TypeLimits,
                          MissingDoc,
                          MissingDebugImplementations,
                          );

    add_lint_group!(sess,
                    "bad_style",
                    NON_CAMEL_CASE_TYPES,
                    NON_SNAKE_CASE,
                    NON_UPPER_CASE_GLOBALS);

    add_lint_group!(sess,
                    "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);

    // Guidelines for creating a future incompatibility lint:
    //
    // - Create a lint defaulting to warn as normal, with ideally the same error
    //   message you would normally give
    // - Add a suitable reference, typically an RFC or tracking issue. Go ahead
    //   and include the full URL.
    // - Later, change lint to error
    // - Eventually, remove lint
    store.register_future_incompatible(sess,
                                       vec![
        FutureIncompatibleInfo {
            id: LintId::of(PRIVATE_IN_PUBLIC),
            reference: "issue #34537 <https://github.com/rust-lang/rust/issues/34537>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(INACCESSIBLE_EXTERN_CRATE),
            reference: "issue #36886 <https://github.com/rust-lang/rust/issues/36886>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(INVALID_TYPE_PARAM_DEFAULT),
            reference: "issue #36887 <https://github.com/rust-lang/rust/issues/36887>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(SUPER_OR_SELF_IN_GLOBAL_PATH),
            reference: "issue #36888 <https://github.com/rust-lang/rust/issues/36888>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(ILLEGAL_FLOATING_POINT_CONSTANT_PATTERN),
            reference: "issue #36890 <https://github.com/rust-lang/rust/issues/36890>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(ILLEGAL_FLOATING_POINT_LITERAL_PATTERN),
            reference: "issue #41620 <https://github.com/rust-lang/rust/issues/41620>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(ILLEGAL_STRUCT_OR_ENUM_CONSTANT_PATTERN),
            reference: "issue #36891 <https://github.com/rust-lang/rust/issues/36891>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(HR_LIFETIME_IN_ASSOC_TYPE),
            reference: "issue #33685 <https://github.com/rust-lang/rust/issues/33685>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(LIFETIME_UNDERSCORE),
            reference: "issue #36892 <https://github.com/rust-lang/rust/issues/36892>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(RESOLVE_TRAIT_ON_DEFAULTED_UNIT),
            reference: "issue #39216 <https://github.com/rust-lang/rust/issues/39216>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(SAFE_EXTERN_STATICS),
            reference: "issue #36247 <https://github.com/rust-lang/rust/issues/35112>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(PATTERNS_IN_FNS_WITHOUT_BODY),
            reference: "issue #35203 <https://github.com/rust-lang/rust/issues/35203>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(EXTRA_REQUIREMENT_IN_IMPL),
            reference: "issue #37166 <https://github.com/rust-lang/rust/issues/37166>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(LEGACY_DIRECTORY_OWNERSHIP),
            reference: "issue #37872 <https://github.com/rust-lang/rust/issues/37872>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(LEGACY_IMPORTS),
            reference: "issue #38260 <https://github.com/rust-lang/rust/issues/38260>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(LEGACY_CONSTRUCTOR_VISIBILITY),
            reference: "issue #39207 <https://github.com/rust-lang/rust/issues/39207>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(MISSING_FRAGMENT_SPECIFIER),
            reference: "issue #40107 <https://github.com/rust-lang/rust/issues/40107>",
        },
        FutureIncompatibleInfo {
            id: LintId::of(ANONYMOUS_PARAMETERS),
            reference: "issue #41686 <https://github.com/rust-lang/rust/issues/41686>",
        },
        ]);

    // Register renamed and removed lints
    store.register_renamed("unknown_features", "unused_features");
    store.register_removed("unsigned_negation",
                           "replaced by negate_unsigned feature gate");
    store.register_removed("negate_unsigned", "cast a signed value instead");
    store.register_removed("raw_pointer_derive", "using derive with raw pointers is ok");
    // This was renamed to raw_pointer_derive, which was then removed,
    // so it is also considered removed
    store.register_removed("raw_pointer_deriving",
                           "using derive with raw pointers is ok");
    store.register_removed("drop_with_repr_extern", "drop flags have been removed");
    store.register_removed("transmute_from_fn_item_types",
        "always cast functions before transmuting them");
    store.register_removed("overlapping_inherent_impls", "converted into hard error, see #36889");
}