src/bootstrap/tool.rs

   1 use std::collections::HashSet;
   2 use std::env;
   3 use std::fs;
   4 use std::path::PathBuf;
   5 use std::process::{exit, Command};
   6
   7 use build_helper::t;
   8
   9 use crate::builder::{Builder, Cargo as CargoCommand, RunConfig, ShouldRun, Step};
  10 use crate::channel;
  11 use crate::channel::GitInfo;
  12 use crate::compile;
  13 use crate::config::TargetSelection;
  14 use crate::toolstate::ToolState;
  15 use crate::util::{add_dylib_path, exe};
  16 use crate::Compiler;
  17 use crate::Mode;
  18
  19 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
  20 pub enum SourceType {
  21     InTree,
  22     Submodule,
  23 }
  24
  25 #[derive(Debug, Clone, Hash, PartialEq, Eq)]
  26 struct ToolBuild {
  27     compiler: Compiler,
  28     target: TargetSelection,
  29     tool: &'static str,
  30     path: &'static str,
  31     mode: Mode,
  32     is_optional_tool: bool,
  33     source_type: SourceType,
  34     extra_features: Vec<String>,
  35 }
  36
  37 impl Step for ToolBuild {
  38     type Output = Option<PathBuf>;
  39
  40     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
  41         run.never()
  42     }
  43
  44     /// Builds a tool in `src/tools`
  45     ///
  46     /// This will build the specified tool with the specified `host` compiler in
  47     /// `stage` into the normal cargo output directory.
  48     fn run(self, builder: &Builder<'_>) -> Option<PathBuf> {
  49         let compiler = self.compiler;
  50         let target = self.target;
  51         let tool = self.tool;
  52         let path = self.path;
  53         let is_optional_tool = self.is_optional_tool;
  54
  55         match self.mode {
  56             Mode::ToolRustc => builder.ensure(compile::Rustc { compiler, target }),
  57             Mode::ToolStd => builder.ensure(compile::Std { compiler, target }),
  58             Mode::ToolBootstrap => {} // uses downloaded stage0 compiler libs
  59             _ => panic!("unexpected Mode for tool build"),
  60         }
  61
  62         let cargo = prepare_tool_cargo(
  63             builder,
  64             compiler,
  65             self.mode,
  66             target,
  67             "build",
  68             path,
  69             self.source_type,
  70             &self.extra_features,
  71         );
  72
  73         builder.info(&format!("Building stage{} tool {} ({})", compiler.stage, tool, target));
  74         let mut duplicates = Vec::new();
  75         let is_expected = compile::stream_cargo(builder, cargo, vec![], &mut |msg| {
  76             // Only care about big things like the RLS/Cargo for now
  77             match tool {
  78                 "rls" | "cargo" | "clippy-driver" | "miri" | "rustfmt" => {}
  79
  80                 _ => return,
  81             }
  82             let (id, features, filenames) = match msg {
  83                 compile::CargoMessage::CompilerArtifact {
  84                     package_id,
  85                     features,
  86                     filenames,
  87                     target: _,
  88                 } => (package_id, features, filenames),
  89                 _ => return,
  90             };
  91             let features = features.iter().map(|s| s.to_string()).collect::<Vec<_>>();
  92
  93             for path in filenames {
  94                 let val = (tool, PathBuf::from(&*path), features.clone());
  95                 // we're only interested in deduplicating rlibs for now
  96                 if val.1.extension().and_then(|s| s.to_str()) != Some("rlib") {
  97                     continue;
  98                 }
  99
 100                 // Don't worry about compiles that turn out to be host
 101                 // dependencies or build scripts. To skip these we look for
 102                 // anything that goes in `.../release/deps` but *doesn't* go in
 103                 // `$target/release/deps`. This ensure that outputs in
 104                 // `$target/release` are still considered candidates for
 105                 // deduplication.
 106                 if let Some(parent) = val.1.parent() {
 107                     if parent.ends_with("release/deps") {
 108                         let maybe_target = parent
 109                             .parent()
 110                             .and_then(|p| p.parent())
 111                             .and_then(|p| p.file_name())
 112                             .and_then(|p| p.to_str())
 113                             .unwrap();
 114                         if maybe_target != &*target.triple {
 115                             continue;
 116                         }
 117                     }
 118                 }
 119
 120                 // Record that we've built an artifact for `id`, and if one was
 121                 // already listed then we need to see if we reused the same
 122                 // artifact or produced a duplicate.
 123                 let mut artifacts = builder.tool_artifacts.borrow_mut();
 124                 let prev_artifacts = artifacts.entry(target).or_default();
 125                 let prev = match prev_artifacts.get(&*id) {
 126                     Some(prev) => prev,
 127                     None => {
 128                         prev_artifacts.insert(id.to_string(), val);
 129                         continue;
 130                     }
 131                 };
 132                 if prev.1 == val.1 {
 133                     return; // same path, same artifact
 134                 }
 135
 136                 // If the paths are different and one of them *isn't* inside of
 137                 // `release/deps`, then it means it's probably in
 138                 // `$target/release`, or it's some final artifact like
 139                 // `libcargo.rlib`. In these situations Cargo probably just
 140                 // copied it up from `$target/release/deps/libcargo-xxxx.rlib`,
 141                 // so if the features are equal we can just skip it.
 142                 let prev_no_hash = prev.1.parent().unwrap().ends_with("release/deps");
 143                 let val_no_hash = val.1.parent().unwrap().ends_with("release/deps");
 144                 if prev.2 == val.2 || !prev_no_hash || !val_no_hash {
 145                     return;
 146                 }
 147
 148                 // ... and otherwise this looks like we duplicated some sort of
 149                 // compilation, so record it to generate an error later.
 150                 duplicates.push((id.to_string(), val, prev.clone()));
 151             }
 152         });
 153
 154         if is_expected && !duplicates.is_empty() {
 155             println!(
 156                 "duplicate artifacts found when compiling a tool, this \
 157                       typically means that something was recompiled because \
 158                       a transitive dependency has different features activated \
 159                       than in a previous build:\n"
 160             );
 161             println!(
 162                 "the following dependencies are duplicated although they \
 163                       have the same features enabled:"
 164             );
 165             let (same, different): (Vec<_>, Vec<_>) =
 166                 duplicates.into_iter().partition(|(_, cur, prev)| cur.2 == prev.2);
 167             for (id, cur, prev) in same {
 168                 println!("  {}", id);
 169                 // same features
 170                 println!("    `{}` ({:?})\n    `{}` ({:?})", cur.0, cur.1, prev.0, prev.1);
 171             }
 172             println!("the following dependencies have different features:");
 173             for (id, cur, prev) in different {
 174                 println!("  {}", id);
 175                 let cur_features: HashSet<_> = cur.2.into_iter().collect();
 176                 let prev_features: HashSet<_> = prev.2.into_iter().collect();
 177                 println!(
 178                     "    `{}` additionally enabled features {:?} at {:?}",
 179                     cur.0,
 180                     &cur_features - &prev_features,
 181                     cur.1
 182                 );
 183                 println!(
 184                     "    `{}` additionally enabled features {:?} at {:?}",
 185                     prev.0,
 186                     &prev_features - &cur_features,
 187                     prev.1
 188                 );
 189             }
 190             println!();
 191             println!(
 192                 "to fix this you will probably want to edit the local \
 193                       src/tools/rustc-workspace-hack/Cargo.toml crate, as \
 194                       that will update the dependency graph to ensure that \
 195                       these crates all share the same feature set"
 196             );
 197             panic!("tools should not compile multiple copies of the same crate");
 198         }
 199
 200         builder.save_toolstate(
 201             tool,
 202             if is_expected { ToolState::TestFail } else { ToolState::BuildFail },
 203         );
 204
 205         if !is_expected {
 206             if !is_optional_tool {
 207                 exit(1);
 208             } else {
 209                 None
 210             }
 211         } else {
 212             let cargo_out =
 213                 builder.cargo_out(compiler, self.mode, target).join(exe(tool, compiler.host));
 214             let bin = builder.tools_dir(compiler).join(exe(tool, compiler.host));
 215             builder.copy(&cargo_out, &bin);
 216             Some(bin)
 217         }
 218     }
 219 }
 220
 221 pub fn prepare_tool_cargo(
 222     builder: &Builder<'_>,
 223     compiler: Compiler,
 224     mode: Mode,
 225     target: TargetSelection,
 226     command: &'static str,
 227     path: &'static str,
 228     source_type: SourceType,
 229     extra_features: &[String],
 230 ) -> CargoCommand {
 231     let mut cargo = builder.cargo(compiler, mode, source_type, target, command);
 232     let dir = builder.src.join(path);
 233     cargo.arg("--manifest-path").arg(dir.join("Cargo.toml"));
 234
 235     let mut features = extra_features.to_vec();
 236     if builder.build.config.cargo_native_static {
 237         if path.ends_with("cargo")
 238             || path.ends_with("rls")
 239             || path.ends_with("clippy")
 240             || path.ends_with("miri")
 241             || path.ends_with("rustfmt")
 242         {
 243             cargo.env("LIBZ_SYS_STATIC", "1");
 244             features.push("rustc-workspace-hack/all-static".to_string());
 245         }
 246     }
 247
 248     // if tools are using lzma we want to force the build script to build its
 249     // own copy
 250     cargo.env("LZMA_API_STATIC", "1");
 251
 252     // CFG_RELEASE is needed by rustfmt (and possibly other tools) which
 253     // import rustc-ap-rustc_attr which requires this to be set for the
 254     // `#[cfg(version(...))]` attribute.
 255     cargo.env("CFG_RELEASE", builder.rust_release());
 256     cargo.env("CFG_RELEASE_CHANNEL", &builder.config.channel);
 257     cargo.env("CFG_VERSION", builder.rust_version());
 258     cargo.env("CFG_RELEASE_NUM", channel::CFG_RELEASE_NUM);
 259
 260     let info = GitInfo::new(builder.config.ignore_git, &dir);
 261     if let Some(sha) = info.sha() {
 262         cargo.env("CFG_COMMIT_HASH", sha);
 263     }
 264     if let Some(sha_short) = info.sha_short() {
 265         cargo.env("CFG_SHORT_COMMIT_HASH", sha_short);
 266     }
 267     if let Some(date) = info.commit_date() {
 268         cargo.env("CFG_COMMIT_DATE", date);
 269     }
 270     if !features.is_empty() {
 271         cargo.arg("--features").arg(&features.join(", "));
 272     }
 273     cargo
 274 }
 275
 276 macro_rules! bootstrap_tool {
 277     ($(
 278         $name:ident, $path:expr, $tool_name:expr
 279         $(,is_external_tool = $external:expr)*
 280         $(,is_unstable_tool = $unstable:expr)*
 281         $(,features = $features:expr)*
 282         ;
 283     )+) => {
 284         #[derive(Copy, PartialEq, Eq, Clone)]
 285         pub enum Tool {
 286             $(
 287                 $name,
 288             )+
 289         }
 290
 291         impl<'a> Builder<'a> {
 292             pub fn tool_exe(&self, tool: Tool) -> PathBuf {
 293                 match tool {
 294                     $(Tool::$name =>
 295                         self.ensure($name {
 296                             compiler: self.compiler(0, self.config.build),
 297                             target: self.config.build,
 298                         }),
 299                     )+
 300                 }
 301             }
 302         }
 303
 304         $(
 305             #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
 306         pub struct $name {
 307             pub compiler: Compiler,
 308             pub target: TargetSelection,
 309         }
 310
 311         impl Step for $name {
 312             type Output = PathBuf;
 313
 314             fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
 315                 run.path($path)
 316             }
 317
 318             fn make_run(run: RunConfig<'_>) {
 319                 run.builder.ensure($name {
 320                     // snapshot compiler
 321                     compiler: run.builder.compiler(0, run.builder.config.build),
 322                     target: run.target,
 323                 });
 324             }
 325
 326             fn run(self, builder: &Builder<'_>) -> PathBuf {
 327                 builder.ensure(ToolBuild {
 328                     compiler: self.compiler,
 329                     target: self.target,
 330                     tool: $tool_name,
 331                     mode: if false $(|| $unstable)* {
 332                         // use in-tree libraries for unstable features
 333                         Mode::ToolStd
 334                     } else {
 335                         Mode::ToolBootstrap
 336                     },
 337                     path: $path,
 338                     is_optional_tool: false,
 339                     source_type: if false $(|| $external)* {
 340                         SourceType::Submodule
 341                     } else {
 342                         SourceType::InTree
 343                     },
 344                     extra_features: {
 345                         // FIXME(#60643): avoid this lint by using `_`
 346                         let mut _tmp = Vec::new();
 347                         $(_tmp.extend($features);)*
 348                         _tmp
 349                     },
 350                 }).expect("expected to build -- essential tool")
 351             }
 352         }
 353         )+
 354     }
 355 }
 356
 357 bootstrap_tool!(
 358     Rustbook, "src/tools/rustbook", "rustbook";
 359     UnstableBookGen, "src/tools/unstable-book-gen", "unstable-book-gen";
 360     Tidy, "src/tools/tidy", "tidy";
 361     Linkchecker, "src/tools/linkchecker", "linkchecker";
 362     CargoTest, "src/tools/cargotest", "cargotest";
 363     Compiletest, "src/tools/compiletest", "compiletest", is_unstable_tool = true;
 364     BuildManifest, "src/tools/build-manifest", "build-manifest";
 365     RemoteTestClient, "src/tools/remote-test-client", "remote-test-client";
 366     RustDemangler, "src/tools/rust-demangler", "rust-demangler";
 367     RustInstaller, "src/tools/rust-installer", "fabricate", is_external_tool = true;
 368     RustdocTheme, "src/tools/rustdoc-themes", "rustdoc-themes";
 369     ExpandYamlAnchors, "src/tools/expand-yaml-anchors", "expand-yaml-anchors";
 370     LintDocs, "src/tools/lint-docs", "lint-docs";
 371 );
 372
 373 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq, Ord, PartialOrd)]
 374 pub struct ErrorIndex {
 375     pub compiler: Compiler,
 376 }
 377
 378 impl ErrorIndex {
 379     pub fn command(builder: &Builder<'_>, compiler: Compiler) -> Command {
 380         let mut cmd = Command::new(builder.ensure(ErrorIndex { compiler }));
 381         add_dylib_path(
 382             vec![PathBuf::from(&builder.sysroot_libdir(compiler, compiler.host))],
 383             &mut cmd,
 384         );
 385         cmd
 386     }
 387 }
 388
 389 impl Step for ErrorIndex {
 390     type Output = PathBuf;
 391
 392     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
 393         run.path("src/tools/error_index_generator")
 394     }
 395
 396     fn make_run(run: RunConfig<'_>) {
 397         // Compile the error-index in the same stage as rustdoc to avoid
 398         // recompiling rustdoc twice if we can.
 399         let host = run.builder.config.build;
 400         let compiler = run.builder.compiler_for(run.builder.top_stage, host, host);
 401         run.builder.ensure(ErrorIndex { compiler });
 402     }
 403
 404     fn run(self, builder: &Builder<'_>) -> PathBuf {
 405         builder
 406             .ensure(ToolBuild {
 407                 compiler: self.compiler,
 408                 target: self.compiler.host,
 409                 tool: "error_index_generator",
 410                 mode: Mode::ToolRustc,
 411                 path: "src/tools/error_index_generator",
 412                 is_optional_tool: false,
 413                 source_type: SourceType::InTree,
 414                 extra_features: Vec::new(),
 415             })
 416             .expect("expected to build -- essential tool")
 417     }
 418 }
 419
 420 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
 421 pub struct RemoteTestServer {
 422     pub compiler: Compiler,
 423     pub target: TargetSelection,
 424 }
 425
 426 impl Step for RemoteTestServer {
 427     type Output = PathBuf;
 428
 429     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
 430         run.path("src/tools/remote-test-server")
 431     }
 432
 433     fn make_run(run: RunConfig<'_>) {
 434         run.builder.ensure(RemoteTestServer {
 435             compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
 436             target: run.target,
 437         });
 438     }
 439
 440     fn run(self, builder: &Builder<'_>) -> PathBuf {
 441         builder
 442             .ensure(ToolBuild {
 443                 compiler: self.compiler,
 444                 target: self.target,
 445                 tool: "remote-test-server",
 446                 mode: Mode::ToolStd,
 447                 path: "src/tools/remote-test-server",
 448                 is_optional_tool: false,
 449                 source_type: SourceType::InTree,
 450                 extra_features: Vec::new(),
 451             })
 452             .expect("expected to build -- essential tool")
 453     }
 454 }
 455
 456 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq, Ord, PartialOrd)]
 457 pub struct Rustdoc {
 458     /// This should only ever be 0 or 2.
 459     /// We sometimes want to reference the "bootstrap" rustdoc, which is why this option is here.
 460     pub compiler: Compiler,
 461 }
 462
 463 impl Step for Rustdoc {
 464     type Output = PathBuf;
 465     const DEFAULT: bool = true;
 466     const ONLY_HOSTS: bool = true;
 467
 468     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
 469         run.path("src/tools/rustdoc").path("src/librustdoc")
 470     }
 471
 472     fn make_run(run: RunConfig<'_>) {
 473         run.builder.ensure(Rustdoc {
 474             compiler: run.builder.compiler(run.builder.top_stage, run.build_triple()),
 475         });
 476     }
 477
 478     fn run(self, builder: &Builder<'_>) -> PathBuf {
 479         let target_compiler = self.compiler;
 480         if target_compiler.stage == 0 {
 481             if !target_compiler.is_snapshot(builder) {
 482                 panic!("rustdoc in stage 0 must be snapshot rustdoc");
 483             }
 484             return builder.initial_rustc.with_file_name(exe("rustdoc", target_compiler.host));
 485         }
 486         let target = target_compiler.host;
 487         // Similar to `compile::Assemble`, build with the previous stage's compiler. Otherwise
 488         // we'd have stageN/bin/rustc and stageN/bin/rustdoc be effectively different stage
 489         // compilers, which isn't what we want. Rustdoc should be linked in the same way as the
 490         // rustc compiler it's paired with, so it must be built with the previous stage compiler.
 491         let build_compiler = builder.compiler(target_compiler.stage - 1, builder.config.build);
 492
 493         // The presence of `target_compiler` ensures that the necessary libraries (codegen backends,
 494         // compiler libraries, ...) are built. Rustdoc does not require the presence of any
 495         // libraries within sysroot_libdir (i.e., rustlib), though doctests may want it (since
 496         // they'll be linked to those libraries). As such, don't explicitly `ensure` any additional
 497         // libraries here. The intuition here is that If we've built a compiler, we should be able
 498         // to build rustdoc.
 499
 500         let cargo = prepare_tool_cargo(
 501             builder,
 502             build_compiler,
 503             Mode::ToolRustc,
 504             target,
 505             "build",
 506             "src/tools/rustdoc",
 507             SourceType::InTree,
 508             &[],
 509         );
 510
 511         builder.info(&format!(
 512             "Building rustdoc for stage{} ({})",
 513             target_compiler.stage, target_compiler.host
 514         ));
 515         builder.run(&mut cargo.into());
 516
 517         // Cargo adds a number of paths to the dylib search path on windows, which results in
 518         // the wrong rustdoc being executed. To avoid the conflicting rustdocs, we name the "tool"
 519         // rustdoc a different name.
 520         let tool_rustdoc = builder
 521             .cargo_out(build_compiler, Mode::ToolRustc, target)
 522             .join(exe("rustdoc_tool_binary", target_compiler.host));
 523
 524         // don't create a stage0-sysroot/bin directory.
 525         if target_compiler.stage > 0 {
 526             let sysroot = builder.sysroot(target_compiler);
 527             let bindir = sysroot.join("bin");
 528             t!(fs::create_dir_all(&bindir));
 529             let bin_rustdoc = bindir.join(exe("rustdoc", target_compiler.host));
 530             let _ = fs::remove_file(&bin_rustdoc);
 531             builder.copy(&tool_rustdoc, &bin_rustdoc);
 532             bin_rustdoc
 533         } else {
 534             tool_rustdoc
 535         }
 536     }
 537 }
 538
 539 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
 540 pub struct Cargo {
 541     pub compiler: Compiler,
 542     pub target: TargetSelection,
 543 }
 544
 545 impl Step for Cargo {
 546     type Output = PathBuf;
 547     const DEFAULT: bool = true;
 548     const ONLY_HOSTS: bool = true;
 549
 550     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
 551         let builder = run.builder;
 552         run.path("src/tools/cargo").default_condition(builder.config.extended)
 553     }
 554
 555     fn make_run(run: RunConfig<'_>) {
 556         run.builder.ensure(Cargo {
 557             compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
 558             target: run.target,
 559         });
 560     }
 561
 562     fn run(self, builder: &Builder<'_>) -> PathBuf {
 563         builder
 564             .ensure(ToolBuild {
 565                 compiler: self.compiler,
 566                 target: self.target,
 567                 tool: "cargo",
 568                 mode: Mode::ToolRustc,
 569                 path: "src/tools/cargo",
 570                 is_optional_tool: false,
 571                 source_type: SourceType::Submodule,
 572                 extra_features: Vec::new(),
 573             })
 574             .expect("expected to build -- essential tool")
 575     }
 576 }
 577
 578 macro_rules! tool_extended {
 579     (($sel:ident, $builder:ident),
 580        $($name:ident,
 581        $toolstate:ident,
 582        $path:expr,
 583        $tool_name:expr,
 584        stable = $stable:expr,
 585        $(in_tree = $in_tree:expr,)*
 586        $extra_deps:block;)+) => {
 587         $(
 588             #[derive(Debug, Clone, Hash, PartialEq, Eq)]
 589         pub struct $name {
 590             pub compiler: Compiler,
 591             pub target: TargetSelection,
 592             pub extra_features: Vec<String>,
 593         }
 594
 595         impl Step for $name {
 596             type Output = Option<PathBuf>;
 597             const DEFAULT: bool = true; // Overwritten below
 598             const ONLY_HOSTS: bool = true;
 599
 600             fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
 601                 let builder = run.builder;
 602                 run.path($path).default_condition(
 603                     builder.config.extended
 604                         && builder.config.tools.as_ref().map_or(
 605                             // By default, on nightly/dev enable all tools, else only
 606                             // build stable tools.
 607                             $stable || builder.build.unstable_features(),
 608                             // If `tools` is set, search list for this tool.
 609                             |tools| {
 610                                 tools.iter().any(|tool| match tool.as_ref() {
 611                                     "clippy" => $tool_name == "clippy-driver",
 612                                     x => $tool_name == x,
 613                             })
 614                         }),
 615                 )
 616             }
 617
 618             fn make_run(run: RunConfig<'_>) {
 619                 run.builder.ensure($name {
 620                     compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
 621                     target: run.target,
 622                     extra_features: Vec::new(),
 623                 });
 624             }
 625
 626             #[allow(unused_mut)]
 627             fn run(mut $sel, $builder: &Builder<'_>) -> Option<PathBuf> {
 628                 $extra_deps
 629                 $builder.ensure(ToolBuild {
 630                     compiler: $sel.compiler,
 631                     target: $sel.target,
 632                     tool: $tool_name,
 633                     mode: Mode::ToolRustc,
 634                     path: $path,
 635                     extra_features: $sel.extra_features,
 636                     is_optional_tool: true,
 637                     source_type: if false $(|| $in_tree)* {
 638                         SourceType::InTree
 639                     } else {
 640                         SourceType::Submodule
 641                     },
 642                 })
 643             }
 644         }
 645         )+
 646     }
 647 }
 648
 649 // Note: tools need to be also added to `Builder::get_step_descriptions` in `builder.rs`
 650 // to make `./x.py build <tool>` work.
 651 tool_extended!((self, builder),
 652     Cargofmt, rustfmt, "src/tools/rustfmt", "cargo-fmt", stable=true, {};
 653     CargoClippy, clippy, "src/tools/clippy", "cargo-clippy", stable=true, in_tree=true, {};
 654     Clippy, clippy, "src/tools/clippy", "clippy-driver", stable=true, in_tree=true, {};
 655     Miri, miri, "src/tools/miri", "miri", stable=false, {};
 656     CargoMiri, miri, "src/tools/miri/cargo-miri", "cargo-miri", stable=false, {};
 657     Rls, rls, "src/tools/rls", "rls", stable=true, {
 658         builder.ensure(Clippy {
 659             compiler: self.compiler,
 660             target: self.target,
 661             extra_features: Vec::new(),
 662         });
 663         self.extra_features.push("clippy".to_owned());
 664     };
 665     Rustfmt, rustfmt, "src/tools/rustfmt", "rustfmt", stable=true, {};
 666     RustAnalyzer, rust_analyzer, "src/tools/rust-analyzer/crates/rust-analyzer", "rust-analyzer", stable=false, {};
 667 );
 668
 669 impl<'a> Builder<'a> {
 670     /// Gets a `Command` which is ready to run `tool` in `stage` built for
 671     /// `host`.
 672     pub fn tool_cmd(&self, tool: Tool) -> Command {
 673         let mut cmd = Command::new(self.tool_exe(tool));
 674         let compiler = self.compiler(0, self.config.build);
 675         let host = &compiler.host;
 676         // Prepares the `cmd` provided to be able to run the `compiler` provided.
 677         //
 678         // Notably this munges the dynamic library lookup path to point to the
 679         // right location to run `compiler`.
 680         let mut lib_paths: Vec<PathBuf> = vec![
 681             self.build.rustc_snapshot_libdir(),
 682             self.cargo_out(compiler, Mode::ToolBootstrap, *host).join("deps"),
 683         ];
 684
 685         // On MSVC a tool may invoke a C compiler (e.g., compiletest in run-make
 686         // mode) and that C compiler may need some extra PATH modification. Do
 687         // so here.
 688         if compiler.host.contains("msvc") {
 689             let curpaths = env::var_os("PATH").unwrap_or_default();
 690             let curpaths = env::split_paths(&curpaths).collect::<Vec<_>>();
 691             for &(ref k, ref v) in self.cc[&compiler.host].env() {
 692                 if k != "PATH" {
 693                     continue;
 694                 }
 695                 for path in env::split_paths(v) {
 696                     if !curpaths.contains(&path) {
 697                         lib_paths.push(path);
 698                     }
 699                 }
 700             }
 701         }
 702
 703         add_dylib_path(lib_paths, &mut cmd);
 704         cmd
 705     }
 706 }