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::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: Compiler,
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 ONLY_HOSTS: 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;
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
288        // Explicitly pass -p for all compiler crates -- this will force cargo
289        // to also lint the tests/benches/examples for these crates, rather
290        // than just the leaf crate.
291        for krate in &*self.crates {
292            cargo.arg("-p").arg(krate);
293        }
294
295        let _guard = builder.msg(
296            Kind::Clippy,
297            format_args!("compiler{}", crate_description(&self.crates)),
298            Mode::Rustc,
299            build_compiler,
300            target,
301        );
302
303        run_cargo(
304            builder,
305            cargo,
306            lint_args(builder, &self.config, IGNORED_RULES_FOR_STD_AND_RUSTC),
307            &build_stamp::librustc_stamp(builder, build_compiler, target),
308            vec![],
309            true,
310            false,
311        );
312    }
313
314    fn metadata(&self) -> Option<StepMetadata> {
315        Some(StepMetadata::clippy("rustc", self.target).built_by(self.build_compiler))
316    }
317}
318
319#[derive(Debug, Clone, Hash, PartialEq, Eq)]
320pub struct CodegenGcc {
321    build_compiler: Compiler,
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;
351        let target = self.target;
352
353        let 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
364        let _guard =
365            builder.msg(Kind::Clippy, "rustc_codegen_gcc", Mode::ToolRustc, build_compiler, target);
366
367        let stamp = BuildStamp::new(&builder.cargo_out(build_compiler, Mode::Codegen, target))
368            .with_prefix("rustc_codegen_gcc-check");
369
370        run_cargo(
371            builder,
372            cargo,
373            lint_args(builder, &self.config, &[]),
374            &stamp,
375            vec![],
376            true,
377            false,
378        );
379    }
380
381    fn metadata(&self) -> Option<StepMetadata> {
382        Some(StepMetadata::clippy("rustc_codegen_gcc", self.target).built_by(self.build_compiler))
383    }
384}
385
386macro_rules! lint_any {
387    ($(
388        $name:ident,
389        $path:expr,
390        $readable_name:expr,
391        $mode:expr
392        $(,lint_by_default = $lint_by_default:expr)*
393        ;
394    )+) => {
395        $(
396
397        #[derive(Debug, Clone, Hash, PartialEq, Eq)]
398        pub struct $name {
399            build_compiler: Compiler,
400            target: TargetSelection,
401            config: LintConfig,
402        }
403
404        impl Step for $name {
405            type Output = ();
406            const DEFAULT: bool = if false $(|| $lint_by_default)* { true } else { false };
407
408            fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
409                run.path($path)
410            }
411
412            fn make_run(run: RunConfig<'_>) {
413                let config = LintConfig::new(run.builder);
414                run.builder.ensure($name {
415                    build_compiler: prepare_compiler_for_check(run.builder, run.target, $mode),
416                    target: run.target,
417                    config,
418                });
419            }
420
421            fn run(self, builder: &Builder<'_>) -> Self::Output {
422                let build_compiler = self.build_compiler;
423                let target = self.target;
424                let cargo = prepare_tool_cargo(
425                    builder,
426                    build_compiler,
427                    $mode,
428                    target,
429                    Kind::Clippy,
430                    $path,
431                    SourceType::InTree,
432                    &[],
433                );
434
435                let _guard = builder.msg(
436                    Kind::Clippy,
437                    $readable_name,
438                    $mode,
439                    build_compiler,
440                    target,
441                );
442
443                let stringified_name = stringify!($name).to_lowercase();
444                let stamp = BuildStamp::new(&builder.cargo_out(build_compiler, $mode, target))
445                    .with_prefix(&format!("{}-check", stringified_name));
446
447                run_cargo(
448                    builder,
449                    cargo,
450                    lint_args(builder, &self.config, &[]),
451                    &stamp,
452                    vec![],
453                    true,
454                    false,
455                );
456            }
457
458            fn metadata(&self) -> Option<StepMetadata> {
459                Some(StepMetadata::clippy($readable_name, self.target).built_by(self.build_compiler))
460            }
461        }
462        )+
463    }
464}
465
466// Note: we use ToolTarget instead of ToolBootstrap here, to allow linting in-tree host tools
467// using the in-tree Clippy. Because Mode::ToolBootstrap would always use stage 0 rustc/Clippy.
468lint_any!(
469    Bootstrap, "src/bootstrap", "bootstrap", Mode::ToolTarget;
470    BuildHelper, "src/build_helper", "build_helper", Mode::ToolTarget;
471    BuildManifest, "src/tools/build-manifest", "build-manifest", Mode::ToolTarget;
472    CargoMiri, "src/tools/miri/cargo-miri", "cargo-miri", Mode::ToolRustc;
473    Clippy, "src/tools/clippy", "clippy", Mode::ToolRustc;
474    CollectLicenseMetadata, "src/tools/collect-license-metadata", "collect-license-metadata", Mode::ToolTarget;
475    Compiletest, "src/tools/compiletest", "compiletest", Mode::ToolTarget;
476    CoverageDump, "src/tools/coverage-dump", "coverage-dump", Mode::ToolTarget;
477    Jsondocck, "src/tools/jsondocck", "jsondocck", Mode::ToolTarget;
478    Jsondoclint, "src/tools/jsondoclint", "jsondoclint", Mode::ToolTarget;
479    LintDocs, "src/tools/lint-docs", "lint-docs", Mode::ToolTarget;
480    LlvmBitcodeLinker, "src/tools/llvm-bitcode-linker", "llvm-bitcode-linker", Mode::ToolTarget;
481    Miri, "src/tools/miri", "miri", Mode::ToolRustc;
482    MiroptTestTools, "src/tools/miropt-test-tools", "miropt-test-tools", Mode::ToolTarget;
483    OptDist, "src/tools/opt-dist", "opt-dist", Mode::ToolTarget;
484    RemoteTestClient, "src/tools/remote-test-client", "remote-test-client", Mode::ToolTarget;
485    RemoteTestServer, "src/tools/remote-test-server", "remote-test-server", Mode::ToolTarget;
486    RustAnalyzer, "src/tools/rust-analyzer", "rust-analyzer", Mode::ToolRustc;
487    Rustdoc, "src/librustdoc", "clippy", Mode::ToolRustc;
488    Rustfmt, "src/tools/rustfmt", "rustfmt", Mode::ToolRustc;
489    RustInstaller, "src/tools/rust-installer", "rust-installer", Mode::ToolTarget;
490    Tidy, "src/tools/tidy", "tidy", Mode::ToolTarget;
491    TestFloatParse, "src/tools/test-float-parse", "test-float-parse", Mode::ToolStd;
492);
493
494/// Runs Clippy on in-tree sources of selected projects using in-tree CLippy.
495#[derive(Debug, Clone, PartialEq, Eq, Hash)]
496pub struct CI {
497    target: TargetSelection,
498    config: LintConfig,
499}
500
501impl Step for CI {
502    type Output = ();
503    const DEFAULT: bool = false;
504
505    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
506        run.alias("ci")
507    }
508
509    fn make_run(run: RunConfig<'_>) {
510        let config = LintConfig::new(run.builder);
511        run.builder.ensure(CI { target: run.target, config });
512    }
513
514    fn run(self, builder: &Builder<'_>) -> Self::Output {
515        if builder.top_stage != 2 {
516            eprintln!("ERROR: `x clippy ci` should always be executed with --stage 2");
517            exit!(1);
518        }
519
520        // We want to check in-tree source using in-tree clippy. However, if we naively did
521        // a stage 2 `x clippy ci`, it would *build* a stage 2 rustc, in order to lint stage 2
522        // std, which is wasteful.
523        // So we want to lint stage 2 [bootstrap/rustc/...], but only stage 1 std rustc_codegen_gcc.
524        // We thus construct the compilers in this step manually, to optimize the number of
525        // steps that get built.
526
527        builder.ensure(Bootstrap {
528            // This will be the stage 1 compiler
529            build_compiler: prepare_compiler_for_check(builder, self.target, Mode::ToolTarget),
530            target: self.target,
531            config: self.config.merge(&LintConfig {
532                allow: vec![],
533                warn: vec![],
534                deny: vec!["warnings".into()],
535                forbid: vec![],
536            }),
537        });
538
539        let library_clippy_cfg = LintConfig {
540            allow: vec!["clippy::all".into()],
541            warn: vec![],
542            deny: vec![
543                "clippy::correctness".into(),
544                "clippy::char_lit_as_u8".into(),
545                "clippy::four_forward_slashes".into(),
546                "clippy::needless_bool".into(),
547                "clippy::needless_bool_assign".into(),
548                "clippy::non_minimal_cfg".into(),
549                "clippy::print_literal".into(),
550                "clippy::same_item_push".into(),
551                "clippy::single_char_add_str".into(),
552                "clippy::to_string_in_format_args".into(),
553            ],
554            forbid: vec![],
555        };
556        builder.ensure(Std::from_build_compiler(
557            // This will be the stage 1 compiler, to avoid building rustc stage 2 just to lint std
558            builder.compiler(1, self.target),
559            self.target,
560            self.config.merge(&library_clippy_cfg),
561            vec![],
562        ));
563
564        let compiler_clippy_cfg = LintConfig {
565            allow: vec!["clippy::all".into()],
566            warn: vec![],
567            deny: vec![
568                "clippy::correctness".into(),
569                "clippy::char_lit_as_u8".into(),
570                "clippy::clone_on_ref_ptr".into(),
571                "clippy::format_in_format_args".into(),
572                "clippy::four_forward_slashes".into(),
573                "clippy::needless_bool".into(),
574                "clippy::needless_bool_assign".into(),
575                "clippy::non_minimal_cfg".into(),
576                "clippy::print_literal".into(),
577                "clippy::same_item_push".into(),
578                "clippy::single_char_add_str".into(),
579                "clippy::to_string_in_format_args".into(),
580            ],
581            forbid: vec![],
582        };
583        // This will lint stage 2 rustc using stage 1 Clippy
584        builder.ensure(Rustc::new(
585            builder,
586            self.target,
587            self.config.merge(&compiler_clippy_cfg),
588            vec![],
589        ));
590
591        let rustc_codegen_gcc = LintConfig {
592            allow: vec![],
593            warn: vec![],
594            deny: vec!["warnings".into()],
595            forbid: vec![],
596        };
597        // This will check stage 2 rustc
598        builder.ensure(CodegenGcc::new(
599            builder,
600            self.target,
601            self.config.merge(&rustc_codegen_gcc),
602        ));
603    }
604}
bootstrap/core/build_steps/clippy.rs

bootstrap/core/build_steps/
clippy.rs
