src/bootstrap/config.rs

   1 //! Serialized configuration of a build.
   2 //!
   3 //! This module implements parsing `config.toml` configuration files to tweak
   4 //! how the build runs.
   5
   6 use std::cmp;
   7 use std::collections::{HashMap, HashSet};
   8 use std::env;
   9 use std::ffi::OsString;
  10 use std::fmt;
  11 use std::fs;
  12 use std::path::{Path, PathBuf};
  13 use std::str::FromStr;
  14
  15 use crate::cache::{Interned, INTERNER};
  16 use crate::channel::GitInfo;
  17 pub use crate::flags::Subcommand;
  18 use crate::flags::{Color, Flags};
  19 use crate::util::exe;
  20 use build_helper::t;
  21 use merge::Merge;
  22 use serde::Deserialize;
  23
  24 macro_rules! check_ci_llvm {
  25     ($name:expr) => {
  26         assert!(
  27             $name.is_none(),
  28             "setting {} is incompatible with download-ci-llvm.",
  29             stringify!($name)
  30         );
  31     };
  32 }
  33
  34 /// Global configuration for the entire build and/or bootstrap.
  35 ///
  36 /// This structure is derived from a combination of both `config.toml` and
  37 /// `config.mk`. As of the time of this writing it's unlikely that `config.toml`
  38 /// is used all that much, so this is primarily filled out by `config.mk` which
  39 /// is generated from `./configure`.
  40 ///
  41 /// Note that this structure is not decoded directly into, but rather it is
  42 /// filled out from the decoded forms of the structs below. For documentation
  43 /// each field, see the corresponding fields in
  44 /// `config.toml.example`.
  45 #[derive(Default)]
  46 pub struct Config {
  47     pub changelog_seen: Option<usize>,
  48     pub ccache: Option<String>,
  49     /// Call Build::ninja() instead of this.
  50     pub ninja_in_file: bool,
  51     pub verbose: usize,
  52     pub submodules: Option<bool>,
  53     pub fast_submodules: bool,
  54     pub compiler_docs: bool,
  55     pub docs_minification: bool,
  56     pub docs: bool,
  57     pub locked_deps: bool,
  58     pub vendor: bool,
  59     pub target_config: HashMap<TargetSelection, Target>,
  60     pub full_bootstrap: bool,
  61     pub extended: bool,
  62     pub tools: Option<HashSet<String>>,
  63     pub sanitizers: bool,
  64     pub profiler: bool,
  65     pub ignore_git: bool,
  66     pub exclude: Vec<PathBuf>,
  67     pub include_default_paths: bool,
  68     pub rustc_error_format: Option<String>,
  69     pub json_output: bool,
  70     pub test_compare_mode: bool,
  71     pub llvm_libunwind: LlvmLibunwind,
  72     pub color: Color,
  73
  74     pub on_fail: Option<String>,
  75     pub stage: u32,
  76     pub keep_stage: Vec<u32>,
  77     pub keep_stage_std: Vec<u32>,
  78     pub src: PathBuf,
  79     // defaults to `config.toml`
  80     pub config: PathBuf,
  81     pub jobs: Option<u32>,
  82     pub cmd: Subcommand,
  83     pub incremental: bool,
  84     pub dry_run: bool,
  85     pub download_rustc: bool,
  86
  87     pub deny_warnings: bool,
  88     pub backtrace_on_ice: bool,
  89
  90     // llvm codegen options
  91     pub llvm_skip_rebuild: bool,
  92     pub llvm_assertions: bool,
  93     pub llvm_tests: bool,
  94     pub llvm_plugins: bool,
  95     pub llvm_optimize: bool,
  96     pub llvm_thin_lto: bool,
  97     pub llvm_release_debuginfo: bool,
  98     pub llvm_version_check: bool,
  99     pub llvm_static_stdcpp: bool,
 100     pub llvm_link_shared: bool,
 101     pub llvm_clang_cl: Option<String>,
 102     pub llvm_targets: Option<String>,
 103     pub llvm_experimental_targets: Option<String>,
 104     pub llvm_link_jobs: Option<u32>,
 105     pub llvm_version_suffix: Option<String>,
 106     pub llvm_use_linker: Option<String>,
 107     pub llvm_allow_old_toolchain: bool,
 108     pub llvm_polly: bool,
 109     pub llvm_clang: bool,
 110     pub llvm_from_ci: bool,
 111
 112     pub use_lld: bool,
 113     pub lld_enabled: bool,
 114     pub llvm_tools_enabled: bool,
 115
 116     pub llvm_cflags: Option<String>,
 117     pub llvm_cxxflags: Option<String>,
 118     pub llvm_ldflags: Option<String>,
 119     pub llvm_use_libcxx: bool,
 120
 121     // rust codegen options
 122     pub rust_optimize: bool,
 123     pub rust_codegen_units: Option<u32>,
 124     pub rust_codegen_units_std: Option<u32>,
 125     pub rust_debug_assertions: bool,
 126     pub rust_debug_assertions_std: bool,
 127     pub rust_overflow_checks: bool,
 128     pub rust_overflow_checks_std: bool,
 129     pub rust_debug_logging: bool,
 130     pub rust_debuginfo_level_rustc: u32,
 131     pub rust_debuginfo_level_std: u32,
 132     pub rust_debuginfo_level_tools: u32,
 133     pub rust_debuginfo_level_tests: u32,
 134     pub rust_run_dsymutil: bool,
 135     pub rust_rpath: bool,
 136     pub rustc_parallel: bool,
 137     pub rustc_default_linker: Option<String>,
 138     pub rust_optimize_tests: bool,
 139     pub rust_dist_src: bool,
 140     pub rust_codegen_backends: Vec<Interned<String>>,
 141     pub rust_verify_llvm_ir: bool,
 142     pub rust_thin_lto_import_instr_limit: Option<u32>,
 143     pub rust_remap_debuginfo: bool,
 144     pub rust_new_symbol_mangling: Option<bool>,
 145     pub rust_profile_use: Option<String>,
 146     pub rust_profile_generate: Option<String>,
 147     pub llvm_profile_use: Option<String>,
 148     pub llvm_profile_generate: bool,
 149
 150     pub build: TargetSelection,
 151     pub hosts: Vec<TargetSelection>,
 152     pub targets: Vec<TargetSelection>,
 153     pub local_rebuild: bool,
 154     pub jemalloc: bool,
 155     pub control_flow_guard: bool,
 156
 157     // dist misc
 158     pub dist_sign_folder: Option<PathBuf>,
 159     pub dist_upload_addr: Option<String>,
 160     pub dist_compression_formats: Option<Vec<String>>,
 161
 162     // libstd features
 163     pub backtrace: bool, // support for RUST_BACKTRACE
 164
 165     // misc
 166     pub low_priority: bool,
 167     pub channel: String,
 168     pub description: Option<String>,
 169     pub verbose_tests: bool,
 170     pub save_toolstates: Option<PathBuf>,
 171     pub print_step_timings: bool,
 172     pub print_step_rusage: bool,
 173     pub missing_tools: bool,
 174
 175     // Fallback musl-root for all targets
 176     pub musl_root: Option<PathBuf>,
 177     pub prefix: Option<PathBuf>,
 178     pub sysconfdir: Option<PathBuf>,
 179     pub datadir: Option<PathBuf>,
 180     pub docdir: Option<PathBuf>,
 181     pub bindir: PathBuf,
 182     pub libdir: Option<PathBuf>,
 183     pub mandir: Option<PathBuf>,
 184     pub codegen_tests: bool,
 185     pub nodejs: Option<PathBuf>,
 186     pub npm: Option<PathBuf>,
 187     pub gdb: Option<PathBuf>,
 188     pub python: Option<PathBuf>,
 189     pub cargo_native_static: bool,
 190     pub configure_args: Vec<String>,
 191
 192     // These are either the stage0 downloaded binaries or the locally installed ones.
 193     pub initial_cargo: PathBuf,
 194     pub initial_rustc: PathBuf,
 195     pub initial_rustfmt: Option<PathBuf>,
 196     pub out: PathBuf,
 197 }
 198
 199 #[derive(Debug, Clone, Copy, PartialEq)]
 200 pub enum LlvmLibunwind {
 201     No,
 202     InTree,
 203     System,
 204 }
 205
 206 impl Default for LlvmLibunwind {
 207     fn default() -> Self {
 208         Self::No
 209     }
 210 }
 211
 212 impl FromStr for LlvmLibunwind {
 213     type Err = String;
 214
 215     fn from_str(value: &str) -> Result<Self, Self::Err> {
 216         match value {
 217             "no" => Ok(Self::No),
 218             "in-tree" => Ok(Self::InTree),
 219             "system" => Ok(Self::System),
 220             invalid => Err(format!("Invalid value '{}' for rust.llvm-libunwind config.", invalid)),
 221         }
 222     }
 223 }
 224
 225 #[derive(Debug, Copy, Clone, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
 226 pub struct TargetSelection {
 227     pub triple: Interned<String>,
 228     file: Option<Interned<String>>,
 229 }
 230
 231 impl TargetSelection {
 232     pub fn from_user(selection: &str) -> Self {
 233         let path = Path::new(selection);
 234
 235         let (triple, file) = if path.exists() {
 236             let triple = path
 237                 .file_stem()
 238                 .expect("Target specification file has no file stem")
 239                 .to_str()
 240                 .expect("Target specification file stem is not UTF-8");
 241
 242             (triple, Some(selection))
 243         } else {
 244             (selection, None)
 245         };
 246
 247         let triple = INTERNER.intern_str(triple);
 248         let file = file.map(|f| INTERNER.intern_str(f));
 249
 250         Self { triple, file }
 251     }
 252
 253     pub fn rustc_target_arg(&self) -> &str {
 254         self.file.as_ref().unwrap_or(&self.triple)
 255     }
 256
 257     pub fn contains(&self, needle: &str) -> bool {
 258         self.triple.contains(needle)
 259     }
 260
 261     pub fn starts_with(&self, needle: &str) -> bool {
 262         self.triple.starts_with(needle)
 263     }
 264
 265     pub fn ends_with(&self, needle: &str) -> bool {
 266         self.triple.ends_with(needle)
 267     }
 268 }
 269
 270 impl fmt::Display for TargetSelection {
 271     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 272         write!(f, "{}", self.triple)?;
 273         if let Some(file) = self.file {
 274             write!(f, "({})", file)?;
 275         }
 276         Ok(())
 277     }
 278 }
 279
 280 impl PartialEq<&str> for TargetSelection {
 281     fn eq(&self, other: &&str) -> bool {
 282         self.triple == *other
 283     }
 284 }
 285
 286 /// Per-target configuration stored in the global configuration structure.
 287 #[derive(Default)]
 288 pub struct Target {
 289     /// Some(path to llvm-config) if using an external LLVM.
 290     pub llvm_config: Option<PathBuf>,
 291     /// Some(path to FileCheck) if one was specified.
 292     pub llvm_filecheck: Option<PathBuf>,
 293     pub cc: Option<PathBuf>,
 294     pub cxx: Option<PathBuf>,
 295     pub ar: Option<PathBuf>,
 296     pub ranlib: Option<PathBuf>,
 297     pub default_linker: Option<PathBuf>,
 298     pub linker: Option<PathBuf>,
 299     pub ndk: Option<PathBuf>,
 300     pub sanitizers: Option<bool>,
 301     pub profiler: Option<bool>,
 302     pub crt_static: Option<bool>,
 303     pub musl_root: Option<PathBuf>,
 304     pub musl_libdir: Option<PathBuf>,
 305     pub wasi_root: Option<PathBuf>,
 306     pub qemu_rootfs: Option<PathBuf>,
 307     pub no_std: bool,
 308 }
 309
 310 impl Target {
 311     pub fn from_triple(triple: &str) -> Self {
 312         let mut target: Self = Default::default();
 313         if triple.contains("-none") || triple.contains("nvptx") {
 314             target.no_std = true;
 315         }
 316         target
 317     }
 318 }
 319 /// Structure of the `config.toml` file that configuration is read from.
 320 ///
 321 /// This structure uses `Decodable` to automatically decode a TOML configuration
 322 /// file into this format, and then this is traversed and written into the above
 323 /// `Config` structure.
 324 #[derive(Deserialize, Default)]
 325 #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 326 struct TomlConfig {
 327     changelog_seen: Option<usize>,
 328     build: Option<Build>,
 329     install: Option<Install>,
 330     llvm: Option<Llvm>,
 331     rust: Option<Rust>,
 332     target: Option<HashMap<String, TomlTarget>>,
 333     dist: Option<Dist>,
 334     profile: Option<String>,
 335 }
 336
 337 impl Merge for TomlConfig {
 338     fn merge(
 339         &mut self,
 340         TomlConfig { build, install, llvm, rust, dist, target, profile: _, changelog_seen: _ }: Self,
 341     ) {
 342         fn do_merge<T: Merge>(x: &mut Option<T>, y: Option<T>) {
 343             if let Some(new) = y {
 344                 if let Some(original) = x {
 345                     original.merge(new);
 346                 } else {
 347                     *x = Some(new);
 348                 }
 349             }
 350         }
 351         do_merge(&mut self.build, build);
 352         do_merge(&mut self.install, install);
 353         do_merge(&mut self.llvm, llvm);
 354         do_merge(&mut self.rust, rust);
 355         do_merge(&mut self.dist, dist);
 356         assert!(target.is_none(), "merging target-specific config is not currently supported");
 357     }
 358 }
 359
 360 macro_rules! derive_merge {
 361     ($(#[$attr:meta])* struct $name:ident {
 362         $($field:ident: $field_ty:ty,)*
 363     }) => {
 364         $(#[$attr])*
 365         struct $name {
 366             $($field: $field_ty,)*
 367         }
 368
 369         impl Merge for $name {
 370             fn merge(&mut self, other: Self) {
 371                 $(
 372                     Merge::merge(&mut self.$field, other.$field);
 373                 )*
 374             }
 375         }
 376     }
 377 }
 378
 379 derive_merge! {
 380     /// TOML representation of various global build decisions.
 381     #[derive(Deserialize, Default, Clone)]
 382     #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 383     struct Build {
 384         build: Option<String>,
 385         host: Option<Vec<String>>,
 386         target: Option<Vec<String>>,
 387         // This is ignored, the rust code always gets the build directory from the `BUILD_DIR` env variable
 388         build_dir: Option<String>,
 389         cargo: Option<String>,
 390         rustc: Option<String>,
 391         rustfmt: Option<PathBuf>,
 392         docs: Option<bool>,
 393         compiler_docs: Option<bool>,
 394         docs_minification: Option<bool>,
 395         submodules: Option<bool>,
 396         fast_submodules: Option<bool>,
 397         gdb: Option<String>,
 398         nodejs: Option<String>,
 399         npm: Option<String>,
 400         python: Option<String>,
 401         locked_deps: Option<bool>,
 402         vendor: Option<bool>,
 403         full_bootstrap: Option<bool>,
 404         extended: Option<bool>,
 405         tools: Option<HashSet<String>>,
 406         verbose: Option<usize>,
 407         sanitizers: Option<bool>,
 408         profiler: Option<bool>,
 409         cargo_native_static: Option<bool>,
 410         low_priority: Option<bool>,
 411         configure_args: Option<Vec<String>>,
 412         local_rebuild: Option<bool>,
 413         print_step_timings: Option<bool>,
 414         print_step_rusage: Option<bool>,
 415         check_stage: Option<u32>,
 416         doc_stage: Option<u32>,
 417         build_stage: Option<u32>,
 418         test_stage: Option<u32>,
 419         install_stage: Option<u32>,
 420         dist_stage: Option<u32>,
 421         bench_stage: Option<u32>,
 422         patch_binaries_for_nix: Option<bool>,
 423     }
 424 }
 425
 426 derive_merge! {
 427     /// TOML representation of various global install decisions.
 428     #[derive(Deserialize, Default, Clone)]
 429     #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 430     struct Install {
 431         prefix: Option<String>,
 432         sysconfdir: Option<String>,
 433         docdir: Option<String>,
 434         bindir: Option<String>,
 435         libdir: Option<String>,
 436         mandir: Option<String>,
 437         datadir: Option<String>,
 438     }
 439 }
 440
 441 derive_merge! {
 442     /// TOML representation of how the LLVM build is configured.
 443     #[derive(Deserialize, Default)]
 444     #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 445     struct Llvm {
 446         skip_rebuild: Option<bool>,
 447         optimize: Option<bool>,
 448         thin_lto: Option<bool>,
 449         release_debuginfo: Option<bool>,
 450         assertions: Option<bool>,
 451         tests: Option<bool>,
 452         plugins: Option<bool>,
 453         ccache: Option<StringOrBool>,
 454         version_check: Option<bool>,
 455         static_libstdcpp: Option<bool>,
 456         ninja: Option<bool>,
 457         targets: Option<String>,
 458         experimental_targets: Option<String>,
 459         link_jobs: Option<u32>,
 460         link_shared: Option<bool>,
 461         version_suffix: Option<String>,
 462         clang_cl: Option<String>,
 463         cflags: Option<String>,
 464         cxxflags: Option<String>,
 465         ldflags: Option<String>,
 466         use_libcxx: Option<bool>,
 467         use_linker: Option<String>,
 468         allow_old_toolchain: Option<bool>,
 469         polly: Option<bool>,
 470         clang: Option<bool>,
 471         download_ci_llvm: Option<StringOrBool>,
 472     }
 473 }
 474
 475 derive_merge! {
 476     #[derive(Deserialize, Default, Clone)]
 477     #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 478     struct Dist {
 479         sign_folder: Option<String>,
 480         gpg_password_file: Option<String>,
 481         upload_addr: Option<String>,
 482         src_tarball: Option<bool>,
 483         missing_tools: Option<bool>,
 484         compression_formats: Option<Vec<String>>,
 485     }
 486 }
 487
 488 #[derive(Deserialize)]
 489 #[serde(untagged)]
 490 enum StringOrBool {
 491     String(String),
 492     Bool(bool),
 493 }
 494
 495 impl Default for StringOrBool {
 496     fn default() -> StringOrBool {
 497         StringOrBool::Bool(false)
 498     }
 499 }
 500
 501 derive_merge! {
 502     /// TOML representation of how the Rust build is configured.
 503     #[derive(Deserialize, Default)]
 504     #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 505     struct Rust {
 506         optimize: Option<bool>,
 507         debug: Option<bool>,
 508         codegen_units: Option<u32>,
 509         codegen_units_std: Option<u32>,
 510         debug_assertions: Option<bool>,
 511         debug_assertions_std: Option<bool>,
 512         overflow_checks: Option<bool>,
 513         overflow_checks_std: Option<bool>,
 514         debug_logging: Option<bool>,
 515         debuginfo_level: Option<u32>,
 516         debuginfo_level_rustc: Option<u32>,
 517         debuginfo_level_std: Option<u32>,
 518         debuginfo_level_tools: Option<u32>,
 519         debuginfo_level_tests: Option<u32>,
 520         run_dsymutil: Option<bool>,
 521         backtrace: Option<bool>,
 522         incremental: Option<bool>,
 523         parallel_compiler: Option<bool>,
 524         default_linker: Option<String>,
 525         channel: Option<String>,
 526         description: Option<String>,
 527         musl_root: Option<String>,
 528         rpath: Option<bool>,
 529         verbose_tests: Option<bool>,
 530         optimize_tests: Option<bool>,
 531         codegen_tests: Option<bool>,
 532         ignore_git: Option<bool>,
 533         dist_src: Option<bool>,
 534         save_toolstates: Option<String>,
 535         codegen_backends: Option<Vec<String>>,
 536         lld: Option<bool>,
 537         use_lld: Option<bool>,
 538         llvm_tools: Option<bool>,
 539         deny_warnings: Option<bool>,
 540         backtrace_on_ice: Option<bool>,
 541         verify_llvm_ir: Option<bool>,
 542         thin_lto_import_instr_limit: Option<u32>,
 543         remap_debuginfo: Option<bool>,
 544         jemalloc: Option<bool>,
 545         test_compare_mode: Option<bool>,
 546         llvm_libunwind: Option<String>,
 547         control_flow_guard: Option<bool>,
 548         new_symbol_mangling: Option<bool>,
 549         profile_generate: Option<String>,
 550         profile_use: Option<String>,
 551         // ignored; this is set from an env var set by bootstrap.py
 552         download_rustc: Option<StringOrBool>,
 553     }
 554 }
 555
 556 derive_merge! {
 557     /// TOML representation of how each build target is configured.
 558     #[derive(Deserialize, Default)]
 559     #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 560     struct TomlTarget {
 561         cc: Option<String>,
 562         cxx: Option<String>,
 563         ar: Option<String>,
 564         ranlib: Option<String>,
 565         default_linker: Option<PathBuf>,
 566         linker: Option<String>,
 567         llvm_config: Option<String>,
 568         llvm_filecheck: Option<String>,
 569         android_ndk: Option<String>,
 570         sanitizers: Option<bool>,
 571         profiler: Option<bool>,
 572         crt_static: Option<bool>,
 573         musl_root: Option<String>,
 574         musl_libdir: Option<String>,
 575         wasi_root: Option<String>,
 576         qemu_rootfs: Option<String>,
 577         no_std: Option<bool>,
 578     }
 579 }
 580
 581 impl Config {
 582     fn path_from_python(var_key: &str) -> PathBuf {
 583         match env::var_os(var_key) {
 584             Some(var_val) => Self::normalize_python_path(var_val),
 585             _ => panic!("expected '{}' to be set", var_key),
 586         }
 587     }
 588
 589     /// Normalizes paths from Python slightly. We don't trust paths from Python (#49785).
 590     fn normalize_python_path(path: OsString) -> PathBuf {
 591         Path::new(&path).components().collect()
 592     }
 593
 594     pub fn default_opts() -> Config {
 595         let mut config = Config::default();
 596         config.llvm_optimize = true;
 597         config.ninja_in_file = true;
 598         config.llvm_version_check = true;
 599         config.backtrace = true;
 600         config.rust_optimize = true;
 601         config.rust_optimize_tests = true;
 602         config.submodules = None;
 603         config.fast_submodules = true;
 604         config.docs = true;
 605         config.docs_minification = true;
 606         config.rust_rpath = true;
 607         config.channel = "dev".to_string();
 608         config.codegen_tests = true;
 609         config.rust_dist_src = true;
 610         config.rust_codegen_backends = vec![INTERNER.intern_str("llvm")];
 611         config.deny_warnings = true;
 612         config.bindir = "bin".into();
 613
 614         // set by build.rs
 615         config.build = TargetSelection::from_user(&env!("BUILD_TRIPLE"));
 616         let manifest_dir = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
 617         // Undo `src/bootstrap`
 618         config.src = manifest_dir.parent().unwrap().parent().unwrap().to_owned();
 619         config.out = Config::path_from_python("BUILD_DIR");
 620
 621         config.initial_cargo = PathBuf::from(env!("CARGO"));
 622         config.initial_rustc = PathBuf::from(env!("RUSTC"));
 623
 624         config
 625     }
 626
 627     pub fn parse(args: &[String]) -> Config {
 628         let flags = Flags::parse(&args);
 629
 630         let mut config = Config::default_opts();
 631         config.exclude = flags.exclude;
 632         config.include_default_paths = flags.include_default_paths;
 633         config.rustc_error_format = flags.rustc_error_format;
 634         config.json_output = flags.json_output;
 635         config.on_fail = flags.on_fail;
 636         config.jobs = flags.jobs.map(threads_from_config);
 637         config.cmd = flags.cmd;
 638         config.incremental = flags.incremental;
 639         config.dry_run = flags.dry_run;
 640         config.keep_stage = flags.keep_stage;
 641         config.keep_stage_std = flags.keep_stage_std;
 642         config.color = flags.color;
 643         if let Some(value) = flags.deny_warnings {
 644             config.deny_warnings = value;
 645         }
 646         config.llvm_profile_use = flags.llvm_profile_use;
 647         config.llvm_profile_generate = flags.llvm_profile_generate;
 648
 649         if config.dry_run {
 650             let dir = config.out.join("tmp-dry-run");
 651             t!(fs::create_dir_all(&dir));
 652             config.out = dir;
 653         }
 654
 655         #[cfg(test)]
 656         let get_toml = |_| TomlConfig::default();
 657         #[cfg(not(test))]
 658         let get_toml = |file: &Path| {
 659             use std::process;
 660
 661             let contents = t!(fs::read_to_string(file), "`include` config not found");
 662             match toml::from_str(&contents) {
 663                 Ok(table) => table,
 664                 Err(err) => {
 665                     println!("failed to parse TOML configuration '{}': {}", file.display(), err);
 666                     process::exit(2);
 667                 }
 668             }
 669         };
 670
 671         let mut toml = flags.config.as_deref().map(get_toml).unwrap_or_else(TomlConfig::default);
 672         if let Some(include) = &toml.profile {
 673             let mut include_path = config.src.clone();
 674             include_path.push("src");
 675             include_path.push("bootstrap");
 676             include_path.push("defaults");
 677             include_path.push(format!("config.{}.toml", include));
 678             let included_toml = get_toml(&include_path);
 679             toml.merge(included_toml);
 680         }
 681
 682         config.changelog_seen = toml.changelog_seen;
 683         if let Some(cfg) = flags.config {
 684             config.config = cfg;
 685         }
 686
 687         let build = toml.build.unwrap_or_default();
 688
 689         config.hosts = if let Some(arg_host) = flags.host {
 690             arg_host
 691         } else if let Some(file_host) = build.host {
 692             file_host.iter().map(|h| TargetSelection::from_user(h)).collect()
 693         } else {
 694             vec![config.build]
 695         };
 696         config.targets = if let Some(arg_target) = flags.target {
 697             arg_target
 698         } else if let Some(file_target) = build.target {
 699             file_target.iter().map(|h| TargetSelection::from_user(h)).collect()
 700         } else {
 701             // If target is *not* configured, then default to the host
 702             // toolchains.
 703             config.hosts.clone()
 704         };
 705
 706         config.nodejs = build.nodejs.map(PathBuf::from);
 707         config.npm = build.npm.map(PathBuf::from);
 708         config.gdb = build.gdb.map(PathBuf::from);
 709         config.python = build.python.map(PathBuf::from);
 710         config.submodules = build.submodules;
 711         set(&mut config.low_priority, build.low_priority);
 712         set(&mut config.compiler_docs, build.compiler_docs);
 713         set(&mut config.docs_minification, build.docs_minification);
 714         set(&mut config.docs, build.docs);
 715         set(&mut config.fast_submodules, build.fast_submodules);
 716         set(&mut config.locked_deps, build.locked_deps);
 717         set(&mut config.vendor, build.vendor);
 718         set(&mut config.full_bootstrap, build.full_bootstrap);
 719         set(&mut config.extended, build.extended);
 720         config.tools = build.tools;
 721         if build.rustfmt.is_some() {
 722             config.initial_rustfmt = build.rustfmt;
 723         }
 724         set(&mut config.verbose, build.verbose);
 725         set(&mut config.sanitizers, build.sanitizers);
 726         set(&mut config.profiler, build.profiler);
 727         set(&mut config.cargo_native_static, build.cargo_native_static);
 728         set(&mut config.configure_args, build.configure_args);
 729         set(&mut config.local_rebuild, build.local_rebuild);
 730         set(&mut config.print_step_timings, build.print_step_timings);
 731         set(&mut config.print_step_rusage, build.print_step_rusage);
 732
 733         config.verbose = cmp::max(config.verbose, flags.verbose);
 734
 735         if let Some(install) = toml.install {
 736             config.prefix = install.prefix.map(PathBuf::from);
 737             config.sysconfdir = install.sysconfdir.map(PathBuf::from);
 738             config.datadir = install.datadir.map(PathBuf::from);
 739             config.docdir = install.docdir.map(PathBuf::from);
 740             set(&mut config.bindir, install.bindir.map(PathBuf::from));
 741             config.libdir = install.libdir.map(PathBuf::from);
 742             config.mandir = install.mandir.map(PathBuf::from);
 743         }
 744
 745         // We want the llvm-skip-rebuild flag to take precedence over the
 746         // skip-rebuild config.toml option so we store it separately
 747         // so that we can infer the right value
 748         let mut llvm_skip_rebuild = flags.llvm_skip_rebuild;
 749
 750         // Store off these values as options because if they're not provided
 751         // we'll infer default values for them later
 752         let mut llvm_assertions = None;
 753         let mut llvm_tests = None;
 754         let mut llvm_plugins = None;
 755         let mut debug = None;
 756         let mut debug_assertions = None;
 757         let mut debug_assertions_std = None;
 758         let mut overflow_checks = None;
 759         let mut overflow_checks_std = None;
 760         let mut debug_logging = None;
 761         let mut debuginfo_level = None;
 762         let mut debuginfo_level_rustc = None;
 763         let mut debuginfo_level_std = None;
 764         let mut debuginfo_level_tools = None;
 765         let mut debuginfo_level_tests = None;
 766         let mut optimize = None;
 767         let mut ignore_git = None;
 768
 769         if let Some(llvm) = toml.llvm {
 770             match llvm.ccache {
 771                 Some(StringOrBool::String(ref s)) => config.ccache = Some(s.to_string()),
 772                 Some(StringOrBool::Bool(true)) => {
 773                     config.ccache = Some("ccache".to_string());
 774                 }
 775                 Some(StringOrBool::Bool(false)) | None => {}
 776             }
 777             set(&mut config.ninja_in_file, llvm.ninja);
 778             llvm_assertions = llvm.assertions;
 779             llvm_tests = llvm.tests;
 780             llvm_plugins = llvm.plugins;
 781             llvm_skip_rebuild = llvm_skip_rebuild.or(llvm.skip_rebuild);
 782             set(&mut config.llvm_optimize, llvm.optimize);
 783             set(&mut config.llvm_thin_lto, llvm.thin_lto);
 784             set(&mut config.llvm_release_debuginfo, llvm.release_debuginfo);
 785             set(&mut config.llvm_version_check, llvm.version_check);
 786             set(&mut config.llvm_static_stdcpp, llvm.static_libstdcpp);
 787             set(&mut config.llvm_link_shared, llvm.link_shared);
 788             config.llvm_targets = llvm.targets.clone();
 789             config.llvm_experimental_targets = llvm.experimental_targets.clone();
 790             config.llvm_link_jobs = llvm.link_jobs;
 791             config.llvm_version_suffix = llvm.version_suffix.clone();
 792             config.llvm_clang_cl = llvm.clang_cl.clone();
 793
 794             config.llvm_cflags = llvm.cflags.clone();
 795             config.llvm_cxxflags = llvm.cxxflags.clone();
 796             config.llvm_ldflags = llvm.ldflags.clone();
 797             set(&mut config.llvm_use_libcxx, llvm.use_libcxx);
 798             config.llvm_use_linker = llvm.use_linker.clone();
 799             config.llvm_allow_old_toolchain = llvm.allow_old_toolchain.unwrap_or(false);
 800             config.llvm_polly = llvm.polly.unwrap_or(false);
 801             config.llvm_clang = llvm.clang.unwrap_or(false);
 802             config.llvm_from_ci = match llvm.download_ci_llvm {
 803                 Some(StringOrBool::String(s)) => {
 804                     assert!(s == "if-available", "unknown option `{}` for download-ci-llvm", s);
 805                     // This is currently all tier 1 targets and tier 2 targets with host tools
 806                     // (since others may not have CI artifacts)
 807                     // https://doc.rust-lang.org/rustc/platform-support.html#tier-1
 808                     // FIXME: this is duplicated in bootstrap.py
 809                     let supported_platforms = [
 810                         // tier 1
 811                         "aarch64-unknown-linux-gnu",
 812                         "i686-pc-windows-gnu",
 813                         "i686-pc-windows-msvc",
 814                         "i686-unknown-linux-gnu",
 815                         "x86_64-unknown-linux-gnu",
 816                         "x86_64-apple-darwin",
 817                         "x86_64-pc-windows-gnu",
 818                         "x86_64-pc-windows-msvc",
 819                         // tier 2 with host tools
 820                         "aarch64-apple-darwin",
 821                         "aarch64-pc-windows-msvc",
 822                         "aarch64-unknown-linux-musl",
 823                         "arm-unknown-linux-gnueabi",
 824                         "arm-unknown-linux-gnueabihf",
 825                         "armv7-unknown-linux-gnueabihf",
 826                         "mips-unknown-linux-gnu",
 827                         "mips64-unknown-linux-gnuabi64",
 828                         "mips64el-unknown-linux-gnuabi64",
 829                         "mipsel-unknown-linux-gnu",
 830                         "powerpc-unknown-linux-gnu",
 831                         "powerpc64-unknown-linux-gnu",
 832                         "powerpc64le-unknown-linux-gnu",
 833                         "riscv64gc-unknown-linux-gnu",
 834                         "s390x-unknown-linux-gnu",
 835                         "x86_64-unknown-freebsd",
 836                         "x86_64-unknown-illumos",
 837                         "x86_64-unknown-linux-musl",
 838                         "x86_64-unknown-netbsd",
 839                     ];
 840                     supported_platforms.contains(&&*config.build.triple)
 841                 }
 842                 Some(StringOrBool::Bool(b)) => b,
 843                 None => false,
 844             };
 845
 846             if config.llvm_from_ci {
 847                 // None of the LLVM options, except assertions, are supported
 848                 // when using downloaded LLVM. We could just ignore these but
 849                 // that's potentially confusing, so force them to not be
 850                 // explicitly set. The defaults and CI defaults don't
 851                 // necessarily match but forcing people to match (somewhat
 852                 // arbitrary) CI configuration locally seems bad/hard.
 853                 check_ci_llvm!(llvm.optimize);
 854                 check_ci_llvm!(llvm.thin_lto);
 855                 check_ci_llvm!(llvm.release_debuginfo);
 856                 check_ci_llvm!(llvm.link_shared);
 857                 check_ci_llvm!(llvm.static_libstdcpp);
 858                 check_ci_llvm!(llvm.targets);
 859                 check_ci_llvm!(llvm.experimental_targets);
 860                 check_ci_llvm!(llvm.link_jobs);
 861                 check_ci_llvm!(llvm.clang_cl);
 862                 check_ci_llvm!(llvm.version_suffix);
 863                 check_ci_llvm!(llvm.cflags);
 864                 check_ci_llvm!(llvm.cxxflags);
 865                 check_ci_llvm!(llvm.ldflags);
 866                 check_ci_llvm!(llvm.use_libcxx);
 867                 check_ci_llvm!(llvm.use_linker);
 868                 check_ci_llvm!(llvm.allow_old_toolchain);
 869                 check_ci_llvm!(llvm.polly);
 870                 check_ci_llvm!(llvm.clang);
 871                 check_ci_llvm!(llvm.plugins);
 872
 873                 // CI-built LLVM can be either dynamic or static.
 874                 let ci_llvm = config.out.join(&*config.build.triple).join("ci-llvm");
 875                 config.llvm_link_shared = if config.dry_run {
 876                     // just assume dynamic for now
 877                     true
 878                 } else {
 879                     let link_type = t!(
 880                         std::fs::read_to_string(ci_llvm.join("link-type.txt")),
 881                         format!("CI llvm missing: {}", ci_llvm.display())
 882                     );
 883                     link_type == "dynamic"
 884                 };
 885             }
 886
 887             if config.llvm_thin_lto && llvm.link_shared.is_none() {
 888                 // If we're building with ThinLTO on, by default we want to link
 889                 // to LLVM shared, to avoid re-doing ThinLTO (which happens in
 890                 // the link step) with each stage.
 891                 config.llvm_link_shared = true;
 892             }
 893         }
 894
 895         if let Some(rust) = toml.rust {
 896             debug = rust.debug;
 897             debug_assertions = rust.debug_assertions;
 898             debug_assertions_std = rust.debug_assertions_std;
 899             overflow_checks = rust.overflow_checks;
 900             overflow_checks_std = rust.overflow_checks_std;
 901             debug_logging = rust.debug_logging;
 902             debuginfo_level = rust.debuginfo_level;
 903             debuginfo_level_rustc = rust.debuginfo_level_rustc;
 904             debuginfo_level_std = rust.debuginfo_level_std;
 905             debuginfo_level_tools = rust.debuginfo_level_tools;
 906             debuginfo_level_tests = rust.debuginfo_level_tests;
 907             config.rust_run_dsymutil = rust.run_dsymutil.unwrap_or(false);
 908             optimize = rust.optimize;
 909             ignore_git = rust.ignore_git;
 910             config.rust_new_symbol_mangling = rust.new_symbol_mangling;
 911             set(&mut config.rust_optimize_tests, rust.optimize_tests);
 912             set(&mut config.codegen_tests, rust.codegen_tests);
 913             set(&mut config.rust_rpath, rust.rpath);
 914             set(&mut config.jemalloc, rust.jemalloc);
 915             set(&mut config.test_compare_mode, rust.test_compare_mode);
 916             config.llvm_libunwind = rust
 917                 .llvm_libunwind
 918                 .map(|v| v.parse().expect("failed to parse rust.llvm-libunwind"))
 919                 .unwrap_or_default();
 920             set(&mut config.backtrace, rust.backtrace);
 921             set(&mut config.channel, rust.channel);
 922             config.description = rust.description;
 923             set(&mut config.rust_dist_src, rust.dist_src);
 924             set(&mut config.verbose_tests, rust.verbose_tests);
 925             // in the case "false" is set explicitly, do not overwrite the command line args
 926             if let Some(true) = rust.incremental {
 927                 config.incremental = true;
 928             }
 929             set(&mut config.use_lld, rust.use_lld);
 930             set(&mut config.lld_enabled, rust.lld);
 931             set(&mut config.llvm_tools_enabled, rust.llvm_tools);
 932             config.rustc_parallel = rust.parallel_compiler.unwrap_or(false);
 933             config.rustc_default_linker = rust.default_linker;
 934             config.musl_root = rust.musl_root.map(PathBuf::from);
 935             config.save_toolstates = rust.save_toolstates.map(PathBuf::from);
 936             set(&mut config.deny_warnings, flags.deny_warnings.or(rust.deny_warnings));
 937             set(&mut config.backtrace_on_ice, rust.backtrace_on_ice);
 938             set(&mut config.rust_verify_llvm_ir, rust.verify_llvm_ir);
 939             config.rust_thin_lto_import_instr_limit = rust.thin_lto_import_instr_limit;
 940             set(&mut config.rust_remap_debuginfo, rust.remap_debuginfo);
 941             set(&mut config.control_flow_guard, rust.control_flow_guard);
 942
 943             if let Some(ref backends) = rust.codegen_backends {
 944                 config.rust_codegen_backends =
 945                     backends.iter().map(|s| INTERNER.intern_str(s)).collect();
 946             }
 947
 948             config.rust_codegen_units = rust.codegen_units.map(threads_from_config);
 949             config.rust_codegen_units_std = rust.codegen_units_std.map(threads_from_config);
 950             config.rust_profile_use = flags.rust_profile_use.or(rust.profile_use);
 951             config.rust_profile_generate = flags.rust_profile_generate.or(rust.profile_generate);
 952             config.download_rustc = env::var("BOOTSTRAP_DOWNLOAD_RUSTC").as_deref() == Ok("1");
 953         } else {
 954             config.rust_profile_use = flags.rust_profile_use;
 955             config.rust_profile_generate = flags.rust_profile_generate;
 956         }
 957
 958         if let Some(t) = toml.target {
 959             for (triple, cfg) in t {
 960                 let mut target = Target::from_triple(&triple);
 961
 962                 if let Some(ref s) = cfg.llvm_config {
 963                     target.llvm_config = Some(config.src.join(s));
 964                 }
 965                 if let Some(ref s) = cfg.llvm_filecheck {
 966                     target.llvm_filecheck = Some(config.src.join(s));
 967                 }
 968                 if let Some(ref s) = cfg.android_ndk {
 969                     target.ndk = Some(config.src.join(s));
 970                 }
 971                 if let Some(s) = cfg.no_std {
 972                     target.no_std = s;
 973                 }
 974                 target.cc = cfg.cc.map(PathBuf::from);
 975                 target.cxx = cfg.cxx.map(PathBuf::from);
 976                 target.ar = cfg.ar.map(PathBuf::from);
 977                 target.ranlib = cfg.ranlib.map(PathBuf::from);
 978                 target.linker = cfg.linker.map(PathBuf::from);
 979                 target.crt_static = cfg.crt_static;
 980                 target.musl_root = cfg.musl_root.map(PathBuf::from);
 981                 target.musl_libdir = cfg.musl_libdir.map(PathBuf::from);
 982                 target.wasi_root = cfg.wasi_root.map(PathBuf::from);
 983                 target.qemu_rootfs = cfg.qemu_rootfs.map(PathBuf::from);
 984                 target.sanitizers = cfg.sanitizers;
 985                 target.profiler = cfg.profiler;
 986
 987                 config.target_config.insert(TargetSelection::from_user(&triple), target);
 988             }
 989         }
 990
 991         if config.llvm_from_ci {
 992             let triple = &config.build.triple;
 993             let mut build_target = config
 994                 .target_config
 995                 .entry(config.build)
 996                 .or_insert_with(|| Target::from_triple(&triple));
 997
 998             check_ci_llvm!(build_target.llvm_config);
 999             check_ci_llvm!(build_target.llvm_filecheck);
1000             let ci_llvm_bin = config.out.join(&*config.build.triple).join("ci-llvm/bin");
1001             build_target.llvm_config = Some(ci_llvm_bin.join(exe("llvm-config", config.build)));
1002             build_target.llvm_filecheck = Some(ci_llvm_bin.join(exe("FileCheck", config.build)));
1003         }
1004
1005         if let Some(t) = toml.dist {
1006             config.dist_sign_folder = t.sign_folder.map(PathBuf::from);
1007             config.dist_upload_addr = t.upload_addr;
1008             config.dist_compression_formats = t.compression_formats;
1009             set(&mut config.rust_dist_src, t.src_tarball);
1010             set(&mut config.missing_tools, t.missing_tools);
1011         }
1012
1013         config.initial_rustfmt = config.initial_rustfmt.or_else({
1014             let build = config.build;
1015             let initial_rustc = &config.initial_rustc;
1016
1017             move || {
1018                 // Cargo does not provide a RUSTFMT environment variable, so we
1019                 // synthesize it manually.
1020                 let rustfmt = initial_rustc.with_file_name(exe("rustfmt", build));
1021
1022                 if rustfmt.exists() { Some(rustfmt) } else { None }
1023             }
1024         });
1025
1026         // Now that we've reached the end of our configuration, infer the
1027         // default values for all options that we haven't otherwise stored yet.
1028
1029         config.llvm_skip_rebuild = llvm_skip_rebuild.unwrap_or(false);
1030         config.llvm_assertions = llvm_assertions.unwrap_or(false);
1031         config.llvm_tests = llvm_tests.unwrap_or(false);
1032         config.llvm_plugins = llvm_plugins.unwrap_or(false);
1033         config.rust_optimize = optimize.unwrap_or(true);
1034
1035         let default = debug == Some(true);
1036         config.rust_debug_assertions = debug_assertions.unwrap_or(default);
1037         config.rust_debug_assertions_std =
1038             debug_assertions_std.unwrap_or(config.rust_debug_assertions);
1039         config.rust_overflow_checks = overflow_checks.unwrap_or(default);
1040         config.rust_overflow_checks_std =
1041             overflow_checks_std.unwrap_or(config.rust_overflow_checks);
1042
1043         config.rust_debug_logging = debug_logging.unwrap_or(config.rust_debug_assertions);
1044
1045         let with_defaults = |debuginfo_level_specific: Option<u32>| {
1046             debuginfo_level_specific.or(debuginfo_level).unwrap_or(if debug == Some(true) {
1047                 1
1048             } else {
1049                 0
1050             })
1051         };
1052         config.rust_debuginfo_level_rustc = with_defaults(debuginfo_level_rustc);
1053         config.rust_debuginfo_level_std = with_defaults(debuginfo_level_std);
1054         config.rust_debuginfo_level_tools = with_defaults(debuginfo_level_tools);
1055         config.rust_debuginfo_level_tests = debuginfo_level_tests.unwrap_or(0);
1056
1057         let default = config.channel == "dev";
1058         config.ignore_git = ignore_git.unwrap_or(default);
1059
1060         let download_rustc = config.download_rustc;
1061         // See https://github.com/rust-lang/compiler-team/issues/326
1062         config.stage = match config.cmd {
1063             Subcommand::Check { .. } => flags.stage.or(build.check_stage).unwrap_or(0),
1064             // `download-rustc` only has a speed-up for stage2 builds. Default to stage2 unless explicitly overridden.
1065             Subcommand::Doc { .. } => {
1066                 flags.stage.or(build.doc_stage).unwrap_or(if download_rustc { 2 } else { 0 })
1067             }
1068             Subcommand::Build { .. } => {
1069                 flags.stage.or(build.build_stage).unwrap_or(if download_rustc { 2 } else { 1 })
1070             }
1071             Subcommand::Test { .. } => {
1072                 flags.stage.or(build.test_stage).unwrap_or(if download_rustc { 2 } else { 1 })
1073             }
1074             Subcommand::Bench { .. } => flags.stage.or(build.bench_stage).unwrap_or(2),
1075             Subcommand::Dist { .. } => flags.stage.or(build.dist_stage).unwrap_or(2),
1076             Subcommand::Install { .. } => flags.stage.or(build.install_stage).unwrap_or(2),
1077             // These are all bootstrap tools, which don't depend on the compiler.
1078             // The stage we pass shouldn't matter, but use 0 just in case.
1079             Subcommand::Clean { .. }
1080             | Subcommand::Clippy { .. }
1081             | Subcommand::Fix { .. }
1082             | Subcommand::Run { .. }
1083             | Subcommand::Setup { .. }
1084             | Subcommand::Format { .. } => flags.stage.unwrap_or(0),
1085         };
1086
1087         // CI should always run stage 2 builds, unless it specifically states otherwise
1088         #[cfg(not(test))]
1089         if flags.stage.is_none() && crate::CiEnv::current() != crate::CiEnv::None {
1090             match config.cmd {
1091                 Subcommand::Test { .. }
1092                 | Subcommand::Doc { .. }
1093                 | Subcommand::Build { .. }
1094                 | Subcommand::Bench { .. }
1095                 | Subcommand::Dist { .. }
1096                 | Subcommand::Install { .. } => {
1097                     assert_eq!(
1098                         config.stage, 2,
1099                         "x.py should be run with `--stage 2` on CI, but was run with `--stage {}`",
1100                         config.stage,
1101                     );
1102                 }
1103                 Subcommand::Clean { .. }
1104                 | Subcommand::Check { .. }
1105                 | Subcommand::Clippy { .. }
1106                 | Subcommand::Fix { .. }
1107                 | Subcommand::Run { .. }
1108                 | Subcommand::Setup { .. }
1109                 | Subcommand::Format { .. } => {}
1110             }
1111         }
1112
1113         config
1114     }
1115
1116     /// Try to find the relative path of `bindir`, otherwise return it in full.
1117     pub fn bindir_relative(&self) -> &Path {
1118         let bindir = &self.bindir;
1119         if bindir.is_absolute() {
1120             // Try to make it relative to the prefix.
1121             if let Some(prefix) = &self.prefix {
1122                 if let Ok(stripped) = bindir.strip_prefix(prefix) {
1123                     return stripped;
1124                 }
1125             }
1126         }
1127         bindir
1128     }
1129
1130     /// Try to find the relative path of `libdir`.
1131     pub fn libdir_relative(&self) -> Option<&Path> {
1132         let libdir = self.libdir.as_ref()?;
1133         if libdir.is_relative() {
1134             Some(libdir)
1135         } else {
1136             // Try to make it relative to the prefix.
1137             libdir.strip_prefix(self.prefix.as_ref()?).ok()
1138         }
1139     }
1140
1141     pub fn verbose(&self) -> bool {
1142         self.verbose > 0
1143     }
1144
1145     pub fn very_verbose(&self) -> bool {
1146         self.verbose > 1
1147     }
1148
1149     pub fn sanitizers_enabled(&self, target: TargetSelection) -> bool {
1150         self.target_config.get(&target).map(|t| t.sanitizers).flatten().unwrap_or(self.sanitizers)
1151     }
1152
1153     pub fn any_sanitizers_enabled(&self) -> bool {
1154         self.target_config.values().any(|t| t.sanitizers == Some(true)) || self.sanitizers
1155     }
1156
1157     pub fn profiler_enabled(&self, target: TargetSelection) -> bool {
1158         self.target_config.get(&target).map(|t| t.profiler).flatten().unwrap_or(self.profiler)
1159     }
1160
1161     pub fn any_profiler_enabled(&self) -> bool {
1162         self.target_config.values().any(|t| t.profiler == Some(true)) || self.profiler
1163     }
1164
1165     pub fn llvm_enabled(&self) -> bool {
1166         self.rust_codegen_backends.contains(&INTERNER.intern_str("llvm"))
1167     }
1168
1169     pub fn submodules(&self, rust_info: &GitInfo) -> bool {
1170         self.submodules.unwrap_or(rust_info.is_git())
1171     }
1172 }
1173
1174 fn set<T>(field: &mut T, val: Option<T>) {
1175     if let Some(v) = val {
1176         *field = v;
1177     }
1178 }
1179
1180 fn threads_from_config(v: u32) -> u32 {
1181     match v {
1182         0 => num_cpus::get() as u32,
1183         n => n,
1184     }
1185 }