1 use std::collections::HashSet;
4 use std::path::{Path, PathBuf};
5 use std::process::{exit, Command};
9 use crate::builder::{Builder, Cargo as CargoCommand, RunConfig, ShouldRun, Step};
10 use crate::channel::GitInfo;
12 use crate::config::TargetSelection;
13 use crate::toolstate::ToolState;
14 use crate::util::{add_dylib_path, exe};
18 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
24 #[derive(Debug, Clone, Hash, PartialEq, Eq)]
27 target: TargetSelection,
31 is_optional_tool: bool,
32 source_type: SourceType,
33 extra_features: Vec<String>,
36 impl Step for ToolBuild {
37 type Output = Option<PathBuf>;
39 fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
43 /// Builds a tool in `src/tools`
45 /// This will build the specified tool with the specified `host` compiler in
46 /// `stage` into the normal cargo output directory.
47 fn run(self, builder: &Builder<'_>) -> Option<PathBuf> {
48 let compiler = self.compiler;
49 let target = self.target;
50 let mut tool = self.tool;
52 let is_optional_tool = self.is_optional_tool;
56 builder.ensure(compile::Std { compiler, target: compiler.host });
57 builder.ensure(compile::Rustc { compiler, target });
59 Mode::ToolStd => builder.ensure(compile::Std { compiler, target }),
60 Mode::ToolBootstrap => {} // uses downloaded stage0 compiler libs
61 _ => panic!("unexpected Mode for tool build"),
64 let cargo = prepare_tool_cargo(
75 builder.info(&format!("Building stage{} tool {} ({})", compiler.stage, tool, target));
76 let mut duplicates = Vec::new();
77 let is_expected = compile::stream_cargo(builder, cargo, vec![], &mut |msg| {
78 // Only care about big things like the RLS/Cargo for now
80 "rls" | "cargo" | "clippy-driver" | "miri" | "rustfmt" => {}
84 let (id, features, filenames) = match msg {
85 compile::CargoMessage::CompilerArtifact {
90 } => (package_id, features, filenames),
93 let features = features.iter().map(|s| s.to_string()).collect::<Vec<_>>();
95 for path in filenames {
96 let val = (tool, PathBuf::from(&*path), features.clone());
97 // we're only interested in deduplicating rlibs for now
98 if val.1.extension().and_then(|s| s.to_str()) != Some("rlib") {
102 // Don't worry about compiles that turn out to be host
103 // dependencies or build scripts. To skip these we look for
104 // anything that goes in `.../release/deps` but *doesn't* go in
105 // `$target/release/deps`. This ensure that outputs in
106 // `$target/release` are still considered candidates for
108 if let Some(parent) = val.1.parent() {
109 if parent.ends_with("release/deps") {
110 let maybe_target = parent
112 .and_then(|p| p.parent())
113 .and_then(|p| p.file_name())
114 .and_then(|p| p.to_str())
116 if maybe_target != &*target.triple {
122 // Record that we've built an artifact for `id`, and if one was
123 // already listed then we need to see if we reused the same
124 // artifact or produced a duplicate.
125 let mut artifacts = builder.tool_artifacts.borrow_mut();
126 let prev_artifacts = artifacts.entry(target).or_default();
127 let prev = match prev_artifacts.get(&*id) {
130 prev_artifacts.insert(id.to_string(), val);
135 return; // same path, same artifact
138 // If the paths are different and one of them *isn't* inside of
139 // `release/deps`, then it means it's probably in
140 // `$target/release`, or it's some final artifact like
141 // `libcargo.rlib`. In these situations Cargo probably just
142 // copied it up from `$target/release/deps/libcargo-xxxx.rlib`,
143 // so if the features are equal we can just skip it.
144 let prev_no_hash = prev.1.parent().unwrap().ends_with("release/deps");
145 let val_no_hash = val.1.parent().unwrap().ends_with("release/deps");
146 if prev.2 == val.2 || !prev_no_hash || !val_no_hash {
150 // ... and otherwise this looks like we duplicated some sort of
151 // compilation, so record it to generate an error later.
152 duplicates.push((id.to_string(), val, prev.clone()));
156 if is_expected && !duplicates.is_empty() {
158 "duplicate artifacts found when compiling a tool, this \
159 typically means that something was recompiled because \
160 a transitive dependency has different features activated \
161 than in a previous build:\n"
164 "the following dependencies are duplicated although they \
165 have the same features enabled:"
167 let (same, different): (Vec<_>, Vec<_>) =
168 duplicates.into_iter().partition(|(_, cur, prev)| cur.2 == prev.2);
169 for (id, cur, prev) in same {
172 println!(" `{}` ({:?})\n `{}` ({:?})", cur.0, cur.1, prev.0, prev.1);
174 println!("the following dependencies have different features:");
175 for (id, cur, prev) in different {
177 let cur_features: HashSet<_> = cur.2.into_iter().collect();
178 let prev_features: HashSet<_> = prev.2.into_iter().collect();
180 " `{}` additionally enabled features {:?} at {:?}",
182 &cur_features - &prev_features,
186 " `{}` additionally enabled features {:?} at {:?}",
188 &prev_features - &cur_features,
194 "to fix this you will probably want to edit the local \
195 src/tools/rustc-workspace-hack/Cargo.toml crate, as \
196 that will update the dependency graph to ensure that \
197 these crates all share the same feature set"
199 panic!("tools should not compile multiple copies of the same crate");
202 builder.save_toolstate(
204 if is_expected { ToolState::TestFail } else { ToolState::BuildFail },
208 if !is_optional_tool {
214 // HACK(#82501): on Windows, the tools directory gets added to PATH when running tests, and
215 // compiletest confuses HTML tidy with the in-tree tidy. Name the in-tree tidy something
216 // different so the problem doesn't come up.
220 let cargo_out = builder.cargo_out(compiler, self.mode, target).join(exe(tool, target));
221 let bin = builder.tools_dir(compiler).join(exe(tool, target));
222 builder.copy(&cargo_out, &bin);
228 pub fn prepare_tool_cargo(
229 builder: &Builder<'_>,
232 target: TargetSelection,
233 command: &'static str,
235 source_type: SourceType,
236 extra_features: &[String],
238 let mut cargo = builder.cargo(compiler, mode, source_type, target, command);
239 let dir = builder.src.join(path);
240 cargo.arg("--manifest-path").arg(dir.join("Cargo.toml"));
242 let mut features = extra_features.to_vec();
243 if builder.build.config.cargo_native_static {
244 if path.ends_with("cargo")
245 || path.ends_with("rls")
246 || path.ends_with("clippy")
247 || path.ends_with("miri")
248 || path.ends_with("rustfmt")
250 cargo.env("LIBZ_SYS_STATIC", "1");
251 features.push("rustc-workspace-hack/all-static".to_string());
255 // if tools are using lzma we want to force the build script to build its
257 cargo.env("LZMA_API_STATIC", "1");
259 // CFG_RELEASE is needed by rustfmt (and possibly other tools) which
260 // import rustc-ap-rustc_attr which requires this to be set for the
261 // `#[cfg(version(...))]` attribute.
262 cargo.env("CFG_RELEASE", builder.rust_release());
263 cargo.env("CFG_RELEASE_CHANNEL", &builder.config.channel);
264 cargo.env("CFG_VERSION", builder.rust_version());
265 cargo.env("CFG_RELEASE_NUM", &builder.version);
266 cargo.env("DOC_RUST_LANG_ORG_CHANNEL", builder.doc_rust_lang_org_channel());
268 let info = GitInfo::new(builder.config.ignore_git, &dir);
269 if let Some(sha) = info.sha() {
270 cargo.env("CFG_COMMIT_HASH", sha);
272 if let Some(sha_short) = info.sha_short() {
273 cargo.env("CFG_SHORT_COMMIT_HASH", sha_short);
275 if let Some(date) = info.commit_date() {
276 cargo.env("CFG_COMMIT_DATE", date);
278 if !features.is_empty() {
279 cargo.arg("--features").arg(&features.join(", "));
284 macro_rules! bootstrap_tool {
286 $name:ident, $path:expr, $tool_name:expr
287 $(,is_external_tool = $external:expr)*
288 $(,is_unstable_tool = $unstable:expr)*
289 $(,features = $features:expr)*
292 #[derive(Copy, PartialEq, Eq, Clone)]
299 impl<'a> Builder<'a> {
300 pub fn tool_exe(&self, tool: Tool) -> PathBuf {
304 compiler: self.compiler(0, self.config.build),
305 target: self.config.build,
313 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
315 pub compiler: Compiler,
316 pub target: TargetSelection,
319 impl Step for $name {
320 type Output = PathBuf;
322 fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
326 fn make_run(run: RunConfig<'_>) {
327 run.builder.ensure($name {
329 compiler: run.builder.compiler(0, run.builder.config.build),
334 fn run(self, builder: &Builder<'_>) -> PathBuf {
335 builder.ensure(ToolBuild {
336 compiler: self.compiler,
339 mode: if false $(|| $unstable)* {
340 // use in-tree libraries for unstable features
346 is_optional_tool: false,
347 source_type: if false $(|| $external)* {
348 SourceType::Submodule
353 // FIXME(#60643): avoid this lint by using `_`
354 let mut _tmp = Vec::new();
355 $(_tmp.extend($features);)*
358 }).expect("expected to build -- essential tool")
366 Rustbook, "src/tools/rustbook", "rustbook";
367 UnstableBookGen, "src/tools/unstable-book-gen", "unstable-book-gen";
368 Tidy, "src/tools/tidy", "tidy";
369 Linkchecker, "src/tools/linkchecker", "linkchecker";
370 CargoTest, "src/tools/cargotest", "cargotest";
371 Compiletest, "src/tools/compiletest", "compiletest", is_unstable_tool = true;
372 BuildManifest, "src/tools/build-manifest", "build-manifest";
373 RemoteTestClient, "src/tools/remote-test-client", "remote-test-client";
374 RustInstaller, "src/tools/rust-installer", "fabricate", is_external_tool = true;
375 RustdocTheme, "src/tools/rustdoc-themes", "rustdoc-themes";
376 ExpandYamlAnchors, "src/tools/expand-yaml-anchors", "expand-yaml-anchors";
377 LintDocs, "src/tools/lint-docs", "lint-docs";
378 JsonDocCk, "src/tools/jsondocck", "jsondocck";
379 HtmlChecker, "src/tools/html-checker", "html-checker";
380 BumpStage0, "src/tools/bump-stage0", "bump-stage0";
383 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq, Ord, PartialOrd)]
384 pub struct ErrorIndex {
385 pub compiler: Compiler,
389 pub fn command(builder: &Builder<'_>) -> Command {
390 // This uses stage-1 to match the behavior of building rustdoc.
391 // Error-index-generator links with the rustdoc library, so we want to
392 // use the same librustdoc to avoid building rustdoc twice (and to
393 // avoid building the compiler an extra time). This uses
394 // saturating_sub to deal with building with stage 0. (Using stage 0
395 // isn't recommended, since it will fail if any new error index tests
396 // use new syntax, but it should work otherwise.)
397 let compiler = builder.compiler(builder.top_stage.saturating_sub(1), builder.config.build);
398 let mut cmd = Command::new(builder.ensure(ErrorIndex { compiler }));
401 PathBuf::from(&builder.sysroot_libdir(compiler, compiler.host)),
402 PathBuf::from(builder.rustc_libdir(compiler)),
410 impl Step for ErrorIndex {
411 type Output = PathBuf;
413 fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
414 run.path("src/tools/error_index_generator")
417 fn make_run(run: RunConfig<'_>) {
418 // Compile the error-index in the same stage as rustdoc to avoid
419 // recompiling rustdoc twice if we can.
421 // NOTE: This `make_run` isn't used in normal situations, only if you
422 // manually build the tool with `x.py build
423 // src/tools/error-index-generator` which almost nobody does.
424 // Normally, `x.py test` or `x.py doc` will use the
425 // `ErrorIndex::command` function instead.
427 run.builder.compiler(run.builder.top_stage.saturating_sub(1), run.builder.config.build);
428 run.builder.ensure(ErrorIndex { compiler });
431 fn run(self, builder: &Builder<'_>) -> PathBuf {
434 compiler: self.compiler,
435 target: self.compiler.host,
436 tool: "error_index_generator",
437 mode: Mode::ToolRustc,
438 path: "src/tools/error_index_generator",
439 is_optional_tool: false,
440 source_type: SourceType::InTree,
441 extra_features: Vec::new(),
443 .expect("expected to build -- essential tool")
447 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
448 pub struct RemoteTestServer {
449 pub compiler: Compiler,
450 pub target: TargetSelection,
453 impl Step for RemoteTestServer {
454 type Output = PathBuf;
456 fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
457 run.path("src/tools/remote-test-server")
460 fn make_run(run: RunConfig<'_>) {
461 run.builder.ensure(RemoteTestServer {
462 compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
467 fn run(self, builder: &Builder<'_>) -> PathBuf {
470 compiler: self.compiler,
472 tool: "remote-test-server",
474 path: "src/tools/remote-test-server",
475 is_optional_tool: false,
476 source_type: SourceType::InTree,
477 extra_features: Vec::new(),
479 .expect("expected to build -- essential tool")
483 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq, Ord, PartialOrd)]
485 /// This should only ever be 0 or 2.
486 /// We sometimes want to reference the "bootstrap" rustdoc, which is why this option is here.
487 pub compiler: Compiler,
490 impl Step for Rustdoc {
491 type Output = PathBuf;
492 const DEFAULT: bool = true;
493 const ONLY_HOSTS: bool = true;
495 fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
496 run.path("src/tools/rustdoc").path("src/librustdoc")
499 fn make_run(run: RunConfig<'_>) {
500 run.builder.ensure(Rustdoc {
501 // Note: this is somewhat unique in that we actually want a *target*
502 // compiler here, because rustdoc *is* a compiler. We won't be using
503 // this as the compiler to build with, but rather this is "what
504 // compiler are we producing"?
505 compiler: run.builder.compiler(run.builder.top_stage, run.target),
509 fn run(self, builder: &Builder<'_>) -> PathBuf {
510 let target_compiler = self.compiler;
511 if target_compiler.stage == 0 {
512 if !target_compiler.is_snapshot(builder) {
513 panic!("rustdoc in stage 0 must be snapshot rustdoc");
515 return builder.initial_rustc.with_file_name(exe("rustdoc", target_compiler.host));
517 let target = target_compiler.host;
518 // Similar to `compile::Assemble`, build with the previous stage's compiler. Otherwise
519 // we'd have stageN/bin/rustc and stageN/bin/rustdoc be effectively different stage
520 // compilers, which isn't what we want. Rustdoc should be linked in the same way as the
521 // rustc compiler it's paired with, so it must be built with the previous stage compiler.
522 let build_compiler = builder.compiler(target_compiler.stage - 1, builder.config.build);
524 // When using `download-rustc` and a stage0 build_compiler, copying rustc doesn't actually
525 // build stage0 libstd (because the libstd in sysroot has the wrong ABI). Explicitly build
527 builder.ensure(compile::Std { compiler: build_compiler, target: target_compiler.host });
528 builder.ensure(compile::Rustc { compiler: build_compiler, target: target_compiler.host });
529 // NOTE: this implies that `download-rustc` is pretty useless when compiling with the stage0
530 // compiler, since you do just as much work.
531 if !builder.config.dry_run && builder.config.download_rustc && build_compiler.stage == 0 {
533 "warning: `download-rustc` does nothing when building stage1 tools; consider using `--stage 2` instead"
537 // The presence of `target_compiler` ensures that the necessary libraries (codegen backends,
538 // compiler libraries, ...) are built. Rustdoc does not require the presence of any
539 // libraries within sysroot_libdir (i.e., rustlib), though doctests may want it (since
540 // they'll be linked to those libraries). As such, don't explicitly `ensure` any additional
541 // libraries here. The intuition here is that If we've built a compiler, we should be able
544 let mut features = Vec::new();
545 if builder.config.jemalloc {
546 features.push("jemalloc".to_string());
549 let cargo = prepare_tool_cargo(
560 builder.info(&format!(
561 "Building rustdoc for stage{} ({})",
562 target_compiler.stage, target_compiler.host
564 builder.run(&mut cargo.into());
566 // Cargo adds a number of paths to the dylib search path on windows, which results in
567 // the wrong rustdoc being executed. To avoid the conflicting rustdocs, we name the "tool"
568 // rustdoc a different name.
569 let tool_rustdoc = builder
570 .cargo_out(build_compiler, Mode::ToolRustc, target)
571 .join(exe("rustdoc_tool_binary", target_compiler.host));
573 // don't create a stage0-sysroot/bin directory.
574 if target_compiler.stage > 0 {
575 let sysroot = builder.sysroot(target_compiler);
576 let bindir = sysroot.join("bin");
577 t!(fs::create_dir_all(&bindir));
578 let bin_rustdoc = bindir.join(exe("rustdoc", target_compiler.host));
579 let _ = fs::remove_file(&bin_rustdoc);
580 builder.copy(&tool_rustdoc, &bin_rustdoc);
588 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
590 pub compiler: Compiler,
591 pub target: TargetSelection,
594 impl Step for Cargo {
595 type Output = PathBuf;
596 const DEFAULT: bool = true;
597 const ONLY_HOSTS: bool = true;
599 fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
600 let builder = run.builder;
601 run.path("src/tools/cargo").default_condition(
602 builder.config.extended
603 && builder.config.tools.as_ref().map_or(
605 // If `tools` is set, search list for this tool.
606 |tools| tools.iter().any(|tool| tool == "cargo"),
611 fn make_run(run: RunConfig<'_>) {
612 run.builder.ensure(Cargo {
613 compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
618 fn run(self, builder: &Builder<'_>) -> PathBuf {
619 let cargo_bin_path = builder
621 compiler: self.compiler,
624 mode: Mode::ToolRustc,
625 path: "src/tools/cargo",
626 is_optional_tool: false,
627 source_type: SourceType::Submodule,
628 extra_features: Vec::new(),
630 .expect("expected to build -- essential tool");
632 let build_cred = |name, path| {
633 // These credential helpers are currently experimental.
634 // Any build failures will be ignored.
635 let _ = builder.ensure(ToolBuild {
636 compiler: self.compiler,
639 mode: Mode::ToolRustc,
641 is_optional_tool: true,
642 source_type: SourceType::Submodule,
643 extra_features: Vec::new(),
647 if self.target.contains("windows") {
649 "cargo-credential-wincred",
650 "src/tools/cargo/crates/credential/cargo-credential-wincred",
653 if self.target.contains("apple-darwin") {
655 "cargo-credential-macos-keychain",
656 "src/tools/cargo/crates/credential/cargo-credential-macos-keychain",
660 "cargo-credential-1password",
661 "src/tools/cargo/crates/credential/cargo-credential-1password",
667 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
668 pub struct LldWrapper {
669 pub compiler: Compiler,
670 pub target: TargetSelection,
671 pub flavor_feature: &'static str,
674 impl Step for LldWrapper {
675 type Output = PathBuf;
677 fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
681 fn run(self, builder: &Builder<'_>) -> PathBuf {
682 let src_exe = builder
684 compiler: self.compiler,
688 path: "src/tools/lld-wrapper",
689 is_optional_tool: false,
690 source_type: SourceType::InTree,
691 extra_features: vec![self.flavor_feature.to_owned()],
693 .expect("expected to build -- essential tool");
699 macro_rules! tool_extended {
700 (($sel:ident, $builder:ident),
705 stable = $stable:expr,
706 $(in_tree = $in_tree:expr,)?
707 $(submodule = $submodule:literal,)?
708 $extra_deps:block;)+) => {
710 #[derive(Debug, Clone, Hash, PartialEq, Eq)]
712 pub compiler: Compiler,
713 pub target: TargetSelection,
714 pub extra_features: Vec<String>,
717 impl Step for $name {
718 type Output = Option<PathBuf>;
719 const DEFAULT: bool = true; // Overwritten below
720 const ONLY_HOSTS: bool = true;
722 fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
723 let builder = run.builder;
724 run.path($path).default_condition(
725 builder.config.extended
726 && builder.config.tools.as_ref().map_or(
727 // By default, on nightly/dev enable all tools, else only
728 // build stable tools.
729 $stable || builder.build.unstable_features(),
730 // If `tools` is set, search list for this tool.
732 tools.iter().any(|tool| match tool.as_ref() {
733 "clippy" => $tool_name == "clippy-driver",
734 x => $tool_name == x,
740 fn make_run(run: RunConfig<'_>) {
741 run.builder.ensure($name {
742 compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
744 extra_features: Vec::new(),
749 fn run(mut $sel, $builder: &Builder<'_>) -> Option<PathBuf> {
751 $( $builder.update_submodule(&Path::new("src").join("tools").join($submodule)); )?
752 $builder.ensure(ToolBuild {
753 compiler: $sel.compiler,
756 mode: Mode::ToolRustc,
758 extra_features: $sel.extra_features,
759 is_optional_tool: true,
760 source_type: if false $(|| $in_tree)* {
763 SourceType::Submodule
772 // Note: tools need to be also added to `Builder::get_step_descriptions` in `builder.rs`
773 // to make `./x.py build <tool>` work.
774 // Note: Most submodule updates for tools are handled by bootstrap.py, since they're needed just to
775 // invoke Cargo to build bootstrap. See the comment there for more details.
776 tool_extended!((self, builder),
777 Cargofmt, rustfmt, "src/tools/rustfmt", "cargo-fmt", stable=true, in_tree=true, {};
778 CargoClippy, clippy, "src/tools/clippy", "cargo-clippy", stable=true, in_tree=true, {};
779 Clippy, clippy, "src/tools/clippy", "clippy-driver", stable=true, in_tree=true, {};
780 Miri, miri, "src/tools/miri", "miri", stable=false, {};
781 CargoMiri, miri, "src/tools/miri/cargo-miri", "cargo-miri", stable=false, {};
782 Rls, rls, "src/tools/rls", "rls", stable=true, {
783 builder.ensure(Clippy {
784 compiler: self.compiler,
786 extra_features: Vec::new(),
788 self.extra_features.push("clippy".to_owned());
790 RustDemangler, rust_demangler, "src/tools/rust-demangler", "rust-demangler", stable=false, in_tree=true, {};
791 Rustfmt, rustfmt, "src/tools/rustfmt", "rustfmt", stable=true, in_tree=true, {};
792 RustAnalyzer, rust_analyzer, "src/tools/rust-analyzer/crates/rust-analyzer", "rust-analyzer", stable=false, submodule="rust-analyzer", {};
795 impl<'a> Builder<'a> {
796 /// Gets a `Command` which is ready to run `tool` in `stage` built for
798 pub fn tool_cmd(&self, tool: Tool) -> Command {
799 let mut cmd = Command::new(self.tool_exe(tool));
800 let compiler = self.compiler(0, self.config.build);
801 let host = &compiler.host;
802 // Prepares the `cmd` provided to be able to run the `compiler` provided.
804 // Notably this munges the dynamic library lookup path to point to the
805 // right location to run `compiler`.
806 let mut lib_paths: Vec<PathBuf> = vec![
807 self.build.rustc_snapshot_libdir(),
808 self.cargo_out(compiler, Mode::ToolBootstrap, *host).join("deps"),
811 // On MSVC a tool may invoke a C compiler (e.g., compiletest in run-make
812 // mode) and that C compiler may need some extra PATH modification. Do
814 if compiler.host.contains("msvc") {
815 let curpaths = env::var_os("PATH").unwrap_or_default();
816 let curpaths = env::split_paths(&curpaths).collect::<Vec<_>>();
817 for &(ref k, ref v) in self.cc[&compiler.host].env() {
821 for path in env::split_paths(v) {
822 if !curpaths.contains(&path) {
823 lib_paths.push(path);
829 add_dylib_path(lib_paths, &mut cmd);
831 // Provide a RUSTC for this command to use.
832 cmd.env("RUSTC", &self.initial_rustc);