bootstrap/core/build_steps/
clippy.rs

1//! Implementation of running clippy on the compiler, standard library and various tools.
2//!
3//! This serves a double purpose:
4//! - The first is to run Clippy itself on in-tree code, in order to test and dogfood it.
5//! - The second is to actually lint the in-tree codebase on CI, with a hard-coded set of rules,
6//!   which is performed by the `x clippy ci` command.
7//!
8//! In order to prepare a build compiler for running clippy, use the
9//! [prepare_compiler_for_check] function. That prepares a
10//! compiler and a standard library
11//! for running Clippy. The second part (actually building Clippy) is performed inside
12//! [Builder::cargo_clippy_cmd]. It would be nice if this was more explicit, and we actually had
13//! to pass a prebuilt Clippy from the outside when running `cargo clippy`, but that would be
14//! (as usual) a massive undertaking/refactoring.
15
16use build_helper::exit;
17
18use super::compile::{run_cargo, rustc_cargo, std_cargo};
19use super::tool::{SourceType, prepare_tool_cargo};
20use crate::builder::{Builder, ShouldRun};
21use crate::core::build_steps::check::{CompilerForCheck, prepare_compiler_for_check};
22use crate::core::build_steps::compile::std_crates_for_run_make;
23use crate::core::builder;
24use crate::core::builder::{Alias, Kind, RunConfig, Step, StepMetadata, crate_description};
25use crate::utils::build_stamp::{self, BuildStamp};
26use crate::{Compiler, Mode, Subcommand, TargetSelection};
27
28/// Disable the most spammy clippy lints
29const IGNORED_RULES_FOR_STD_AND_RUSTC: &[&str] = &[
30    "many_single_char_names", // there are a lot in stdarch
31    "collapsible_if",
32    "type_complexity",
33    "missing_safety_doc", // almost 3K warnings
34    "too_many_arguments",
35    "needless_lifetimes", // people want to keep the lifetimes
36    "wrong_self_convention",
37    "approx_constant", // libcore is what defines those
38];
39
40fn lint_args(builder: &Builder<'_>, config: &LintConfig, ignored_rules: &[&str]) -> Vec<String> {
41    fn strings<'a>(arr: &'a [&str]) -> impl Iterator<Item = String> + 'a {
42        arr.iter().copied().map(String::from)
43    }
44
45    let Subcommand::Clippy { fix, allow_dirty, allow_staged, .. } = &builder.config.cmd else {
46        unreachable!("clippy::lint_args can only be called from `clippy` subcommands.");
47    };
48
49    let mut args = vec![];
50    if *fix {
51        #[rustfmt::skip]
52            args.extend(strings(&[
53                "--fix", "-Zunstable-options",
54                // FIXME: currently, `--fix` gives an error while checking tests for libtest,
55                // possibly because libtest is not yet built in the sysroot.
56                // As a workaround, avoid checking tests and benches when passed --fix.
57                "--lib", "--bins", "--examples",
58            ]));
59
60        if *allow_dirty {
61            args.push("--allow-dirty".to_owned());
62        }
63
64        if *allow_staged {
65            args.push("--allow-staged".to_owned());
66        }
67    }
68
69    args.extend(strings(&["--"]));
70
71    if config.deny.is_empty() && config.forbid.is_empty() {
72        args.extend(strings(&["--cap-lints", "warn"]));
73    }
74
75    let all_args = std::env::args().collect::<Vec<_>>();
76    args.extend(get_clippy_rules_in_order(&all_args, config));
77
78    args.extend(ignored_rules.iter().map(|lint| format!("-Aclippy::{lint}")));
79    args.extend(builder.config.free_args.clone());
80    args
81}
82
83/// We need to keep the order of the given clippy lint rules before passing them.
84/// Since clap doesn't offer any useful interface for this purpose out of the box,
85/// we have to handle it manually.
86pub fn get_clippy_rules_in_order(all_args: &[String], config: &LintConfig) -> Vec<String> {
87    let mut result = vec![];
88
89    for (prefix, item) in
90        [("-A", &config.allow), ("-D", &config.deny), ("-W", &config.warn), ("-F", &config.forbid)]
91    {
92        item.iter().for_each(|v| {
93            let rule = format!("{prefix}{v}");
94            // Arguments added by bootstrap in LintConfig won't show up in the all_args list, so
95            // put them at the end of the command line.
96            let position = all_args.iter().position(|t| t == &rule || t == v).unwrap_or(usize::MAX);
97            result.push((position, rule));
98        });
99    }
100
101    result.sort_by_key(|&(position, _)| position);
102    result.into_iter().map(|v| v.1).collect()
103}
104
105#[derive(Debug, Clone, PartialEq, Eq, Hash)]
106pub struct LintConfig {
107    pub allow: Vec<String>,
108    pub warn: Vec<String>,
109    pub deny: Vec<String>,
110    pub forbid: Vec<String>,
111}
112
113impl LintConfig {
114    fn new(builder: &Builder<'_>) -> Self {
115        match builder.config.cmd.clone() {
116            Subcommand::Clippy { allow, deny, warn, forbid, .. } => {
117                Self { allow, warn, deny, forbid }
118            }
119            _ => unreachable!("LintConfig can only be called from `clippy` subcommands."),
120        }
121    }
122
123    fn merge(&self, other: &Self) -> Self {
124        let merged = |self_attr: &[String], other_attr: &[String]| -> Vec<String> {
125            self_attr.iter().cloned().chain(other_attr.iter().cloned()).collect()
126        };
127        // This is written this way to ensure we get a compiler error if we add a new field.
128        Self {
129            allow: merged(&self.allow, &other.allow),
130            warn: merged(&self.warn, &other.warn),
131            deny: merged(&self.deny, &other.deny),
132            forbid: merged(&self.forbid, &other.forbid),
133        }
134    }
135}
136
137#[derive(Debug, Clone, PartialEq, Eq, Hash)]
138pub struct Std {
139    build_compiler: Compiler,
140    target: TargetSelection,
141    config: LintConfig,
142    /// Whether to lint only a subset of crates.
143    crates: Vec<String>,
144}
145
146impl Std {
147    fn new(
148        builder: &Builder<'_>,
149        target: TargetSelection,
150        config: LintConfig,
151        crates: Vec<String>,
152    ) -> Self {
153        Self {
154            build_compiler: builder.compiler(builder.top_stage, builder.host_target),
155            target,
156            config,
157            crates,
158        }
159    }
160
161    fn from_build_compiler(
162        build_compiler: Compiler,
163        target: TargetSelection,
164        config: LintConfig,
165        crates: Vec<String>,
166    ) -> Self {
167        Self { build_compiler, target, config, crates }
168    }
169}
170
171impl Step for Std {
172    type Output = ();
173    const DEFAULT: bool = true;
174
175    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
176        run.crate_or_deps("sysroot").path("library")
177    }
178
179    fn make_run(run: RunConfig<'_>) {
180        let crates = std_crates_for_run_make(&run);
181        let config = LintConfig::new(run.builder);
182        run.builder.ensure(Std::new(run.builder, run.target, config, crates));
183    }
184
185    fn run(self, builder: &Builder<'_>) {
186        let target = self.target;
187        let build_compiler = self.build_compiler;
188
189        let mut cargo = builder::Cargo::new(
190            builder,
191            build_compiler,
192            Mode::Std,
193            SourceType::InTree,
194            target,
195            Kind::Clippy,
196        );
197
198        std_cargo(builder, target, &mut cargo);
199
200        for krate in &*self.crates {
201            cargo.arg("-p").arg(krate);
202        }
203
204        let _guard = builder.msg(
205            Kind::Clippy,
206            format_args!("library{}", crate_description(&self.crates)),
207            Mode::Std,
208            build_compiler,
209            target,
210        );
211
212        run_cargo(
213            builder,
214            cargo,
215            lint_args(builder, &self.config, IGNORED_RULES_FOR_STD_AND_RUSTC),
216            &build_stamp::libstd_stamp(builder, build_compiler, target),
217            vec![],
218            true,
219            false,
220        );
221    }
222
223    fn metadata(&self) -> Option<StepMetadata> {
224        Some(StepMetadata::clippy("std", self.target).built_by(self.build_compiler))
225    }
226}
227
228/// Lints the compiler.
229///
230/// This will build Clippy with the `build_compiler` and use it to lint
231/// in-tree rustc.
232#[derive(Debug, Clone, PartialEq, Eq, Hash)]
233pub struct Rustc {
234    build_compiler: CompilerForCheck,
235    target: TargetSelection,
236    config: LintConfig,
237    /// Whether to lint only a subset of crates.
238    crates: Vec<String>,
239}
240
241impl Rustc {
242    fn new(
243        builder: &Builder<'_>,
244        target: TargetSelection,
245        config: LintConfig,
246        crates: Vec<String>,
247    ) -> Self {
248        Self {
249            build_compiler: prepare_compiler_for_check(builder, target, Mode::Rustc),
250            target,
251            config,
252            crates,
253        }
254    }
255}
256
257impl Step for Rustc {
258    type Output = ();
259    const IS_HOST: bool = true;
260    const DEFAULT: bool = true;
261
262    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
263        run.crate_or_deps("rustc-main").path("compiler")
264    }
265
266    fn make_run(run: RunConfig<'_>) {
267        let builder = run.builder;
268        let crates = run.make_run_crates(Alias::Compiler);
269        let config = LintConfig::new(run.builder);
270        run.builder.ensure(Rustc::new(builder, run.target, config, crates));
271    }
272
273    fn run(self, builder: &Builder<'_>) {
274        let build_compiler = self.build_compiler.build_compiler();
275        let target = self.target;
276
277        let mut cargo = builder::Cargo::new(
278            builder,
279            build_compiler,
280            Mode::Rustc,
281            SourceType::InTree,
282            target,
283            Kind::Clippy,
284        );
285
286        rustc_cargo(builder, &mut cargo, target, &build_compiler, &self.crates);
287        self.build_compiler.configure_cargo(&mut cargo);
288
289        // Explicitly pass -p for all compiler crates -- this will force cargo
290        // to also lint the tests/benches/examples for these crates, rather
291        // than just the leaf crate.
292        for krate in &*self.crates {
293            cargo.arg("-p").arg(krate);
294        }
295
296        let _guard = builder.msg(
297            Kind::Clippy,
298            format_args!("compiler{}", crate_description(&self.crates)),
299            Mode::Rustc,
300            build_compiler,
301            target,
302        );
303
304        run_cargo(
305            builder,
306            cargo,
307            lint_args(builder, &self.config, IGNORED_RULES_FOR_STD_AND_RUSTC),
308            &build_stamp::librustc_stamp(builder, build_compiler, target),
309            vec![],
310            true,
311            false,
312        );
313    }
314
315    fn metadata(&self) -> Option<StepMetadata> {
316        Some(
317            StepMetadata::clippy("rustc", self.target)
318                .built_by(self.build_compiler.build_compiler()),
319        )
320    }
321}
322
323#[derive(Debug, Clone, Hash, PartialEq, Eq)]
324pub struct CodegenGcc {
325    build_compiler: CompilerForCheck,
326    target: TargetSelection,
327    config: LintConfig,
328}
329
330impl CodegenGcc {
331    fn new(builder: &Builder<'_>, target: TargetSelection, config: LintConfig) -> Self {
332        Self {
333            build_compiler: prepare_compiler_for_check(builder, target, Mode::Codegen),
334            target,
335            config,
336        }
337    }
338}
339
340impl Step for CodegenGcc {
341    type Output = ();
342
343    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
344        run.alias("rustc_codegen_gcc")
345    }
346
347    fn make_run(run: RunConfig<'_>) {
348        let builder = run.builder;
349        let config = LintConfig::new(builder);
350        builder.ensure(CodegenGcc::new(builder, run.target, config));
351    }
352
353    fn run(self, builder: &Builder<'_>) -> Self::Output {
354        let build_compiler = self.build_compiler.build_compiler();
355        let target = self.target;
356
357        let mut cargo = prepare_tool_cargo(
358            builder,
359            build_compiler,
360            Mode::Codegen,
361            target,
362            Kind::Clippy,
363            "compiler/rustc_codegen_gcc",
364            SourceType::InTree,
365            &[],
366        );
367        self.build_compiler.configure_cargo(&mut cargo);
368
369        let _guard = builder.msg(
370            Kind::Clippy,
371            "rustc_codegen_gcc",
372            Mode::ToolRustcPrivate,
373            build_compiler,
374            target,
375        );
376
377        let stamp = BuildStamp::new(&builder.cargo_out(build_compiler, Mode::Codegen, target))
378            .with_prefix("rustc_codegen_gcc-check");
379
380        run_cargo(
381            builder,
382            cargo,
383            lint_args(builder, &self.config, &[]),
384            &stamp,
385            vec![],
386            true,
387            false,
388        );
389    }
390
391    fn metadata(&self) -> Option<StepMetadata> {
392        Some(
393            StepMetadata::clippy("rustc_codegen_gcc", self.target)
394                .built_by(self.build_compiler.build_compiler()),
395        )
396    }
397}
398
399macro_rules! lint_any {
400    ($(
401        $name:ident,
402        $path:expr,
403        $readable_name:expr,
404        $mode:expr
405        $(,lint_by_default = $lint_by_default:expr)*
406        ;
407    )+) => {
408        $(
409
410        #[derive(Debug, Clone, Hash, PartialEq, Eq)]
411        pub struct $name {
412            build_compiler: CompilerForCheck,
413            target: TargetSelection,
414            config: LintConfig,
415        }
416
417        impl Step for $name {
418            type Output = ();
419            const DEFAULT: bool = if false $(|| $lint_by_default)* { true } else { false };
420
421            fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
422                run.path($path)
423            }
424
425            fn make_run(run: RunConfig<'_>) {
426                let config = LintConfig::new(run.builder);
427                run.builder.ensure($name {
428                    build_compiler: prepare_compiler_for_check(run.builder, run.target, $mode),
429                    target: run.target,
430                    config,
431                });
432            }
433
434            fn run(self, builder: &Builder<'_>) -> Self::Output {
435                let build_compiler = self.build_compiler.build_compiler();
436                let target = self.target;
437                let mut cargo = prepare_tool_cargo(
438                    builder,
439                    build_compiler,
440                    $mode,
441                    target,
442                    Kind::Clippy,
443                    $path,
444                    SourceType::InTree,
445                    &[],
446                );
447                self.build_compiler.configure_cargo(&mut cargo);
448
449                let _guard = builder.msg(
450                    Kind::Clippy,
451                    $readable_name,
452                    $mode,
453                    build_compiler,
454                    target,
455                );
456
457                let stringified_name = stringify!($name).to_lowercase();
458                let stamp = BuildStamp::new(&builder.cargo_out(build_compiler, $mode, target))
459                    .with_prefix(&format!("{}-check", stringified_name));
460
461                run_cargo(
462                    builder,
463                    cargo,
464                    lint_args(builder, &self.config, &[]),
465                    &stamp,
466                    vec![],
467                    true,
468                    false,
469                );
470            }
471
472            fn metadata(&self) -> Option<StepMetadata> {
473                Some(StepMetadata::clippy($readable_name, self.target).built_by(self.build_compiler.build_compiler()))
474            }
475        }
476        )+
477    }
478}
479
480// Note: we use ToolTarget instead of ToolBootstrap here, to allow linting in-tree host tools
481// using the in-tree Clippy. Because Mode::ToolBootstrap would always use stage 0 rustc/Clippy.
482lint_any!(
483    Bootstrap, "src/bootstrap", "bootstrap", Mode::ToolTarget;
484    BuildHelper, "src/build_helper", "build_helper", Mode::ToolTarget;
485    BuildManifest, "src/tools/build-manifest", "build-manifest", Mode::ToolTarget;
486    CargoMiri, "src/tools/miri/cargo-miri", "cargo-miri", Mode::ToolRustcPrivate;
487    Clippy, "src/tools/clippy", "clippy", Mode::ToolRustcPrivate;
488    CollectLicenseMetadata, "src/tools/collect-license-metadata", "collect-license-metadata", Mode::ToolTarget;
489    Compiletest, "src/tools/compiletest", "compiletest", Mode::ToolTarget;
490    CoverageDump, "src/tools/coverage-dump", "coverage-dump", Mode::ToolTarget;
491    Jsondocck, "src/tools/jsondocck", "jsondocck", Mode::ToolTarget;
492    Jsondoclint, "src/tools/jsondoclint", "jsondoclint", Mode::ToolTarget;
493    LintDocs, "src/tools/lint-docs", "lint-docs", Mode::ToolTarget;
494    LlvmBitcodeLinker, "src/tools/llvm-bitcode-linker", "llvm-bitcode-linker", Mode::ToolTarget;
495    Miri, "src/tools/miri", "miri", Mode::ToolRustcPrivate;
496    MiroptTestTools, "src/tools/miropt-test-tools", "miropt-test-tools", Mode::ToolTarget;
497    OptDist, "src/tools/opt-dist", "opt-dist", Mode::ToolTarget;
498    RemoteTestClient, "src/tools/remote-test-client", "remote-test-client", Mode::ToolTarget;
499    RemoteTestServer, "src/tools/remote-test-server", "remote-test-server", Mode::ToolTarget;
500    RustAnalyzer, "src/tools/rust-analyzer", "rust-analyzer", Mode::ToolRustcPrivate;
501    Rustdoc, "src/librustdoc", "clippy", Mode::ToolRustcPrivate;
502    Rustfmt, "src/tools/rustfmt", "rustfmt", Mode::ToolRustcPrivate;
503    RustInstaller, "src/tools/rust-installer", "rust-installer", Mode::ToolTarget;
504    Tidy, "src/tools/tidy", "tidy", Mode::ToolTarget;
505    TestFloatParse, "src/tools/test-float-parse", "test-float-parse", Mode::ToolStd;
506);
507
508/// Runs Clippy on in-tree sources of selected projects using in-tree CLippy.
509#[derive(Debug, Clone, PartialEq, Eq, Hash)]
510pub struct CI {
511    target: TargetSelection,
512    config: LintConfig,
513}
514
515impl Step for CI {
516    type Output = ();
517    const DEFAULT: bool = false;
518
519    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
520        run.alias("ci")
521    }
522
523    fn make_run(run: RunConfig<'_>) {
524        let config = LintConfig::new(run.builder);
525        run.builder.ensure(CI { target: run.target, config });
526    }
527
528    fn run(self, builder: &Builder<'_>) -> Self::Output {
529        if builder.top_stage != 2 {
530            eprintln!("ERROR: `x clippy ci` should always be executed with --stage 2");
531            exit!(1);
532        }
533
534        // We want to check in-tree source using in-tree clippy. However, if we naively did
535        // a stage 2 `x clippy ci`, it would *build* a stage 2 rustc, in order to lint stage 2
536        // std, which is wasteful.
537        // So we want to lint stage 2 [bootstrap/rustc/...], but only stage 1 std rustc_codegen_gcc.
538        // We thus construct the compilers in this step manually, to optimize the number of
539        // steps that get built.
540
541        builder.ensure(Bootstrap {
542            // This will be the stage 1 compiler
543            build_compiler: prepare_compiler_for_check(builder, self.target, Mode::ToolTarget),
544            target: self.target,
545            config: self.config.merge(&LintConfig {
546                allow: vec![],
547                warn: vec![],
548                deny: vec!["warnings".into()],
549                forbid: vec![],
550            }),
551        });
552
553        let library_clippy_cfg = LintConfig {
554            allow: vec!["clippy::all".into()],
555            warn: vec![],
556            deny: vec![
557                "clippy::correctness".into(),
558                "clippy::char_lit_as_u8".into(),
559                "clippy::four_forward_slashes".into(),
560                "clippy::needless_bool".into(),
561                "clippy::needless_bool_assign".into(),
562                "clippy::non_minimal_cfg".into(),
563                "clippy::print_literal".into(),
564                "clippy::same_item_push".into(),
565                "clippy::single_char_add_str".into(),
566                "clippy::to_string_in_format_args".into(),
567            ],
568            forbid: vec![],
569        };
570        builder.ensure(Std::from_build_compiler(
571            // This will be the stage 1 compiler, to avoid building rustc stage 2 just to lint std
572            builder.compiler(1, self.target),
573            self.target,
574            self.config.merge(&library_clippy_cfg),
575            vec![],
576        ));
577
578        let compiler_clippy_cfg = LintConfig {
579            allow: vec!["clippy::all".into()],
580            warn: vec![],
581            deny: vec![
582                "clippy::correctness".into(),
583                "clippy::char_lit_as_u8".into(),
584                "clippy::clone_on_ref_ptr".into(),
585                "clippy::format_in_format_args".into(),
586                "clippy::four_forward_slashes".into(),
587                "clippy::needless_bool".into(),
588                "clippy::needless_bool_assign".into(),
589                "clippy::non_minimal_cfg".into(),
590                "clippy::print_literal".into(),
591                "clippy::same_item_push".into(),
592                "clippy::single_char_add_str".into(),
593                "clippy::to_string_in_format_args".into(),
594            ],
595            forbid: vec![],
596        };
597        // This will lint stage 2 rustc using stage 1 Clippy
598        builder.ensure(Rustc::new(
599            builder,
600            self.target,
601            self.config.merge(&compiler_clippy_cfg),
602            vec![],
603        ));
604
605        let rustc_codegen_gcc = LintConfig {
606            allow: vec![],
607            warn: vec![],
608            deny: vec!["warnings".into()],
609            forbid: vec![],
610        };
611        // This will check stage 2 rustc
612        builder.ensure(CodegenGcc::new(
613            builder,
614            self.target,
615            self.config.merge(&rustc_codegen_gcc),
616        ));
617    }
618}
bootstrap/core/build_steps/clippy.rs

bootstrap/core/build_steps/
clippy.rs
