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, &self.crates);
199
200        let _guard = builder.msg(
201            Kind::Clippy,
202            format_args!("library{}", crate_description(&self.crates)),
203            Mode::Std,
204            build_compiler,
205            target,
206        );
207
208        run_cargo(
209            builder,
210            cargo,
211            lint_args(builder, &self.config, IGNORED_RULES_FOR_STD_AND_RUSTC),
212            &build_stamp::libstd_stamp(builder, build_compiler, target),
213            vec![],
214            true,
215            false,
216        );
217    }
218
219    fn metadata(&self) -> Option<StepMetadata> {
220        Some(StepMetadata::clippy("std", self.target).built_by(self.build_compiler))
221    }
222}
223
224/// Lints the compiler.
225///
226/// This will build Clippy with the `build_compiler` and use it to lint
227/// in-tree rustc.
228#[derive(Debug, Clone, PartialEq, Eq, Hash)]
229pub struct Rustc {
230    build_compiler: CompilerForCheck,
231    target: TargetSelection,
232    config: LintConfig,
233    /// Whether to lint only a subset of crates.
234    crates: Vec<String>,
235}
236
237impl Rustc {
238    fn new(
239        builder: &Builder<'_>,
240        target: TargetSelection,
241        config: LintConfig,
242        crates: Vec<String>,
243    ) -> Self {
244        Self {
245            build_compiler: prepare_compiler_for_check(builder, target, Mode::Rustc),
246            target,
247            config,
248            crates,
249        }
250    }
251}
252
253impl Step for Rustc {
254    type Output = ();
255    const IS_HOST: bool = true;
256    const DEFAULT: bool = true;
257
258    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
259        run.crate_or_deps("rustc-main").path("compiler")
260    }
261
262    fn make_run(run: RunConfig<'_>) {
263        let builder = run.builder;
264        let crates = run.make_run_crates(Alias::Compiler);
265        let config = LintConfig::new(run.builder);
266        run.builder.ensure(Rustc::new(builder, run.target, config, crates));
267    }
268
269    fn run(self, builder: &Builder<'_>) {
270        let build_compiler = self.build_compiler.build_compiler();
271        let target = self.target;
272
273        let mut cargo = builder::Cargo::new(
274            builder,
275            build_compiler,
276            Mode::Rustc,
277            SourceType::InTree,
278            target,
279            Kind::Clippy,
280        );
281
282        rustc_cargo(builder, &mut cargo, target, &build_compiler, &self.crates);
283        self.build_compiler.configure_cargo(&mut cargo);
284
285        // Explicitly pass -p for all compiler crates -- this will force cargo
286        // to also lint the tests/benches/examples for these crates, rather
287        // than just the leaf crate.
288        for krate in &*self.crates {
289            cargo.arg("-p").arg(krate);
290        }
291
292        let _guard = builder.msg(
293            Kind::Clippy,
294            format_args!("compiler{}", crate_description(&self.crates)),
295            Mode::Rustc,
296            build_compiler,
297            target,
298        );
299
300        run_cargo(
301            builder,
302            cargo,
303            lint_args(builder, &self.config, IGNORED_RULES_FOR_STD_AND_RUSTC),
304            &build_stamp::librustc_stamp(builder, build_compiler, target),
305            vec![],
306            true,
307            false,
308        );
309    }
310
311    fn metadata(&self) -> Option<StepMetadata> {
312        Some(
313            StepMetadata::clippy("rustc", self.target)
314                .built_by(self.build_compiler.build_compiler()),
315        )
316    }
317}
318
319#[derive(Debug, Clone, Hash, PartialEq, Eq)]
320pub struct CodegenGcc {
321    build_compiler: CompilerForCheck,
322    target: TargetSelection,
323    config: LintConfig,
324}
325
326impl CodegenGcc {
327    fn new(builder: &Builder<'_>, target: TargetSelection, config: LintConfig) -> Self {
328        Self {
329            build_compiler: prepare_compiler_for_check(builder, target, Mode::Codegen),
330            target,
331            config,
332        }
333    }
334}
335
336impl Step for CodegenGcc {
337    type Output = ();
338
339    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
340        run.alias("rustc_codegen_gcc")
341    }
342
343    fn make_run(run: RunConfig<'_>) {
344        let builder = run.builder;
345        let config = LintConfig::new(builder);
346        builder.ensure(CodegenGcc::new(builder, run.target, config));
347    }
348
349    fn run(self, builder: &Builder<'_>) -> Self::Output {
350        let build_compiler = self.build_compiler.build_compiler();
351        let target = self.target;
352
353        let mut cargo = prepare_tool_cargo(
354            builder,
355            build_compiler,
356            Mode::Codegen,
357            target,
358            Kind::Clippy,
359            "compiler/rustc_codegen_gcc",
360            SourceType::InTree,
361            &[],
362        );
363        self.build_compiler.configure_cargo(&mut cargo);
364
365        let _guard = builder.msg(
366            Kind::Clippy,
367            "rustc_codegen_gcc",
368            Mode::ToolRustcPrivate,
369            build_compiler,
370            target,
371        );
372
373        let stamp = BuildStamp::new(&builder.cargo_out(build_compiler, Mode::Codegen, target))
374            .with_prefix("rustc_codegen_gcc-check");
375
376        run_cargo(
377            builder,
378            cargo,
379            lint_args(builder, &self.config, &[]),
380            &stamp,
381            vec![],
382            true,
383            false,
384        );
385    }
386
387    fn metadata(&self) -> Option<StepMetadata> {
388        Some(
389            StepMetadata::clippy("rustc_codegen_gcc", self.target)
390                .built_by(self.build_compiler.build_compiler()),
391        )
392    }
393}
394
395macro_rules! lint_any {
396    ($(
397        $name:ident,
398        $path:expr,
399        $readable_name:expr,
400        $mode:expr
401        $(,lint_by_default = $lint_by_default:expr)*
402        ;
403    )+) => {
404        $(
405
406        #[derive(Debug, Clone, Hash, PartialEq, Eq)]
407        pub struct $name {
408            build_compiler: CompilerForCheck,
409            target: TargetSelection,
410            config: LintConfig,
411        }
412
413        impl Step for $name {
414            type Output = ();
415            const DEFAULT: bool = if false $(|| $lint_by_default)* { true } else { false };
416
417            fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
418                run.path($path)
419            }
420
421            fn make_run(run: RunConfig<'_>) {
422                let config = LintConfig::new(run.builder);
423                run.builder.ensure($name {
424                    build_compiler: prepare_compiler_for_check(run.builder, run.target, $mode),
425                    target: run.target,
426                    config,
427                });
428            }
429
430            fn run(self, builder: &Builder<'_>) -> Self::Output {
431                let build_compiler = self.build_compiler.build_compiler();
432                let target = self.target;
433                let mut cargo = prepare_tool_cargo(
434                    builder,
435                    build_compiler,
436                    $mode,
437                    target,
438                    Kind::Clippy,
439                    $path,
440                    SourceType::InTree,
441                    &[],
442                );
443                self.build_compiler.configure_cargo(&mut cargo);
444
445                let _guard = builder.msg(
446                    Kind::Clippy,
447                    $readable_name,
448                    $mode,
449                    build_compiler,
450                    target,
451                );
452
453                let stringified_name = stringify!($name).to_lowercase();
454                let stamp = BuildStamp::new(&builder.cargo_out(build_compiler, $mode, target))
455                    .with_prefix(&format!("{}-check", stringified_name));
456
457                run_cargo(
458                    builder,
459                    cargo,
460                    lint_args(builder, &self.config, &[]),
461                    &stamp,
462                    vec![],
463                    true,
464                    false,
465                );
466            }
467
468            fn metadata(&self) -> Option<StepMetadata> {
469                Some(StepMetadata::clippy($readable_name, self.target).built_by(self.build_compiler.build_compiler()))
470            }
471        }
472        )+
473    }
474}
475
476// Note: we use ToolTarget instead of ToolBootstrap here, to allow linting in-tree host tools
477// using the in-tree Clippy. Because Mode::ToolBootstrap would always use stage 0 rustc/Clippy.
478lint_any!(
479    Bootstrap, "src/bootstrap", "bootstrap", Mode::ToolTarget;
480    BuildHelper, "src/build_helper", "build_helper", Mode::ToolTarget;
481    BuildManifest, "src/tools/build-manifest", "build-manifest", Mode::ToolTarget;
482    CargoMiri, "src/tools/miri/cargo-miri", "cargo-miri", Mode::ToolRustcPrivate;
483    Clippy, "src/tools/clippy", "clippy", Mode::ToolRustcPrivate;
484    CollectLicenseMetadata, "src/tools/collect-license-metadata", "collect-license-metadata", Mode::ToolTarget;
485    Compiletest, "src/tools/compiletest", "compiletest", Mode::ToolTarget;
486    CoverageDump, "src/tools/coverage-dump", "coverage-dump", Mode::ToolTarget;
487    Jsondocck, "src/tools/jsondocck", "jsondocck", Mode::ToolTarget;
488    Jsondoclint, "src/tools/jsondoclint", "jsondoclint", Mode::ToolTarget;
489    LintDocs, "src/tools/lint-docs", "lint-docs", Mode::ToolTarget;
490    LlvmBitcodeLinker, "src/tools/llvm-bitcode-linker", "llvm-bitcode-linker", Mode::ToolTarget;
491    Miri, "src/tools/miri", "miri", Mode::ToolRustcPrivate;
492    MiroptTestTools, "src/tools/miropt-test-tools", "miropt-test-tools", Mode::ToolTarget;
493    OptDist, "src/tools/opt-dist", "opt-dist", Mode::ToolTarget;
494    RemoteTestClient, "src/tools/remote-test-client", "remote-test-client", Mode::ToolTarget;
495    RemoteTestServer, "src/tools/remote-test-server", "remote-test-server", Mode::ToolTarget;
496    RustAnalyzer, "src/tools/rust-analyzer", "rust-analyzer", Mode::ToolRustcPrivate;
497    Rustdoc, "src/librustdoc", "clippy", Mode::ToolRustcPrivate;
498    Rustfmt, "src/tools/rustfmt", "rustfmt", Mode::ToolRustcPrivate;
499    RustInstaller, "src/tools/rust-installer", "rust-installer", Mode::ToolTarget;
500    Tidy, "src/tools/tidy", "tidy", Mode::ToolTarget;
501    TestFloatParse, "src/tools/test-float-parse", "test-float-parse", Mode::ToolStd;
502);
503
504/// Runs Clippy on in-tree sources of selected projects using in-tree CLippy.
505#[derive(Debug, Clone, PartialEq, Eq, Hash)]
506pub struct CI {
507    target: TargetSelection,
508    config: LintConfig,
509}
510
511impl Step for CI {
512    type Output = ();
513    const DEFAULT: bool = false;
514
515    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
516        run.alias("ci")
517    }
518
519    fn make_run(run: RunConfig<'_>) {
520        let config = LintConfig::new(run.builder);
521        run.builder.ensure(CI { target: run.target, config });
522    }
523
524    fn run(self, builder: &Builder<'_>) -> Self::Output {
525        if builder.top_stage != 2 {
526            eprintln!("ERROR: `x clippy ci` should always be executed with --stage 2");
527            exit!(1);
528        }
529
530        // We want to check in-tree source using in-tree clippy. However, if we naively did
531        // a stage 2 `x clippy ci`, it would *build* a stage 2 rustc, in order to lint stage 2
532        // std, which is wasteful.
533        // So we want to lint stage 2 [bootstrap/rustc/...], but only stage 1 std rustc_codegen_gcc.
534        // We thus construct the compilers in this step manually, to optimize the number of
535        // steps that get built.
536
537        builder.ensure(Bootstrap {
538            // This will be the stage 1 compiler
539            build_compiler: prepare_compiler_for_check(builder, self.target, Mode::ToolTarget),
540            target: self.target,
541            config: self.config.merge(&LintConfig {
542                allow: vec![],
543                warn: vec![],
544                deny: vec!["warnings".into()],
545                forbid: vec![],
546            }),
547        });
548
549        let library_clippy_cfg = LintConfig {
550            allow: vec!["clippy::all".into()],
551            warn: vec![],
552            deny: vec![
553                "clippy::correctness".into(),
554                "clippy::char_lit_as_u8".into(),
555                "clippy::four_forward_slashes".into(),
556                "clippy::needless_bool".into(),
557                "clippy::needless_bool_assign".into(),
558                "clippy::non_minimal_cfg".into(),
559                "clippy::print_literal".into(),
560                "clippy::same_item_push".into(),
561                "clippy::single_char_add_str".into(),
562                "clippy::to_string_in_format_args".into(),
563                "clippy::unconditional_recursion".into(),
564            ],
565            forbid: vec![],
566        };
567        builder.ensure(Std::from_build_compiler(
568            // This will be the stage 1 compiler, to avoid building rustc stage 2 just to lint std
569            builder.compiler(1, self.target),
570            self.target,
571            self.config.merge(&library_clippy_cfg),
572            vec![],
573        ));
574
575        let compiler_clippy_cfg = LintConfig {
576            allow: vec!["clippy::all".into()],
577            warn: vec![],
578            deny: vec![
579                "clippy::correctness".into(),
580                "clippy::char_lit_as_u8".into(),
581                "clippy::clone_on_ref_ptr".into(),
582                "clippy::format_in_format_args".into(),
583                "clippy::four_forward_slashes".into(),
584                "clippy::needless_bool".into(),
585                "clippy::needless_bool_assign".into(),
586                "clippy::non_minimal_cfg".into(),
587                "clippy::print_literal".into(),
588                "clippy::same_item_push".into(),
589                "clippy::single_char_add_str".into(),
590                "clippy::to_string_in_format_args".into(),
591                "clippy::unconditional_recursion".into(),
592            ],
593            forbid: vec![],
594        };
595        // This will lint stage 2 rustc using stage 1 Clippy
596        builder.ensure(Rustc::new(
597            builder,
598            self.target,
599            self.config.merge(&compiler_clippy_cfg),
600            vec![],
601        ));
602
603        let rustc_codegen_gcc = LintConfig {
604            allow: vec![],
605            warn: vec![],
606            deny: vec!["warnings".into()],
607            forbid: vec![],
608        };
609        // This will check stage 2 rustc
610        builder.ensure(CodegenGcc::new(
611            builder,
612            self.target,
613            self.config.merge(&rustc_codegen_gcc),
614        ));
615    }
616}
bootstrap/core/build_steps/clippy.rs

bootstrap/core/build_steps/
clippy.rs
