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::cell::{Cell, RefCell};
   7 use std::cmp;
   8 use std::collections::{HashMap, HashSet};
   9 use std::env;
  10 use std::ffi::OsStr;
  11 use std::fmt;
  12 use std::fs;
  13 use std::path::{Path, PathBuf};
  14 use std::process::{exit, Command};
  15 use std::str::FromStr;
  16
  17 use crate::builder::{Builder, TaskPath};
  18 use crate::cache::{Interned, INTERNER};
  19 use crate::channel::GitInfo;
  20 pub use crate::flags::Subcommand;
  21 use crate::flags::{Color, Flags};
  22 use crate::util::{exe, output, program_out_of_date, t};
  23 use once_cell::sync::OnceCell;
  24 use serde::{Deserialize, Deserializer};
  25
  26 macro_rules! check_ci_llvm {
  27     ($name:expr) => {
  28         assert!(
  29             $name.is_none(),
  30             "setting {} is incompatible with download-ci-llvm.",
  31             stringify!($name)
  32         );
  33     };
  34 }
  35
  36 /// Global configuration for the entire build and/or bootstrap.
  37 ///
  38 /// This structure is derived from a combination of both `config.toml` and
  39 /// `config.mk`. As of the time of this writing it's unlikely that `config.toml`
  40 /// is used all that much, so this is primarily filled out by `config.mk` which
  41 /// is generated from `./configure`.
  42 ///
  43 /// Note that this structure is not decoded directly into, but rather it is
  44 /// filled out from the decoded forms of the structs below. For documentation
  45 /// each field, see the corresponding fields in
  46 /// `config.toml.example`.
  47 #[derive(Default)]
  48 #[cfg_attr(test, derive(Clone))]
  49 pub struct Config {
  50     pub changelog_seen: Option<usize>,
  51     pub ccache: Option<String>,
  52     /// Call Build::ninja() instead of this.
  53     pub ninja_in_file: bool,
  54     pub verbose: usize,
  55     pub submodules: Option<bool>,
  56     pub compiler_docs: bool,
  57     pub docs_minification: bool,
  58     pub docs: bool,
  59     pub locked_deps: bool,
  60     pub vendor: bool,
  61     pub target_config: HashMap<TargetSelection, Target>,
  62     pub full_bootstrap: bool,
  63     pub extended: bool,
  64     pub tools: Option<HashSet<String>>,
  65     pub sanitizers: bool,
  66     pub profiler: bool,
  67     pub ignore_git: bool,
  68     pub exclude: Vec<TaskPath>,
  69     pub include_default_paths: bool,
  70     pub rustc_error_format: Option<String>,
  71     pub json_output: bool,
  72     pub test_compare_mode: bool,
  73     pub color: Color,
  74     pub patch_binaries_for_nix: bool,
  75
  76     pub on_fail: Option<String>,
  77     pub stage: u32,
  78     pub keep_stage: Vec<u32>,
  79     pub keep_stage_std: Vec<u32>,
  80     pub src: PathBuf,
  81     /// defaults to `config.toml`
  82     pub config: PathBuf,
  83     pub jobs: Option<u32>,
  84     pub cmd: Subcommand,
  85     pub incremental: bool,
  86     pub dry_run: bool,
  87     /// `None` if we shouldn't download CI compiler artifacts, or the commit to download if we should.
  88     #[cfg(not(test))]
  89     download_rustc_commit: Option<String>,
  90     #[cfg(test)]
  91     pub download_rustc_commit: Option<String>,
  92
  93     pub deny_warnings: bool,
  94     pub backtrace_on_ice: bool,
  95
  96     // llvm codegen options
  97     pub llvm_skip_rebuild: bool,
  98     pub llvm_assertions: bool,
  99     pub llvm_tests: bool,
 100     pub llvm_plugins: bool,
 101     pub llvm_optimize: bool,
 102     pub llvm_thin_lto: bool,
 103     pub llvm_release_debuginfo: bool,
 104     pub llvm_version_check: bool,
 105     pub llvm_static_stdcpp: bool,
 106     /// `None` if `llvm_from_ci` is true and we haven't yet downloaded llvm.
 107     #[cfg(not(test))]
 108     llvm_link_shared: Cell<Option<bool>>,
 109     #[cfg(test)]
 110     pub llvm_link_shared: Cell<Option<bool>>,
 111     pub llvm_clang_cl: Option<String>,
 112     pub llvm_targets: Option<String>,
 113     pub llvm_experimental_targets: Option<String>,
 114     pub llvm_link_jobs: Option<u32>,
 115     pub llvm_version_suffix: Option<String>,
 116     pub llvm_use_linker: Option<String>,
 117     pub llvm_allow_old_toolchain: bool,
 118     pub llvm_polly: bool,
 119     pub llvm_clang: bool,
 120     pub llvm_from_ci: bool,
 121     pub llvm_build_config: HashMap<String, String>,
 122
 123     pub use_lld: bool,
 124     pub lld_enabled: bool,
 125     pub llvm_tools_enabled: bool,
 126
 127     pub llvm_cflags: Option<String>,
 128     pub llvm_cxxflags: Option<String>,
 129     pub llvm_ldflags: Option<String>,
 130     pub llvm_use_libcxx: bool,
 131
 132     // rust codegen options
 133     pub rust_optimize: bool,
 134     pub rust_codegen_units: Option<u32>,
 135     pub rust_codegen_units_std: Option<u32>,
 136     pub rust_debug_assertions: bool,
 137     pub rust_debug_assertions_std: bool,
 138     pub rust_overflow_checks: bool,
 139     pub rust_overflow_checks_std: bool,
 140     pub rust_debug_logging: bool,
 141     pub rust_debuginfo_level_rustc: u32,
 142     pub rust_debuginfo_level_std: u32,
 143     pub rust_debuginfo_level_tools: u32,
 144     pub rust_debuginfo_level_tests: u32,
 145     pub rust_split_debuginfo: SplitDebuginfo,
 146     pub rust_rpath: bool,
 147     pub rustc_parallel: bool,
 148     pub rustc_default_linker: Option<String>,
 149     pub rust_optimize_tests: bool,
 150     pub rust_dist_src: bool,
 151     pub rust_codegen_backends: Vec<Interned<String>>,
 152     pub rust_verify_llvm_ir: bool,
 153     pub rust_thin_lto_import_instr_limit: Option<u32>,
 154     pub rust_remap_debuginfo: bool,
 155     pub rust_new_symbol_mangling: Option<bool>,
 156     pub rust_profile_use: Option<String>,
 157     pub rust_profile_generate: Option<String>,
 158     pub llvm_profile_use: Option<String>,
 159     pub llvm_profile_generate: bool,
 160     pub llvm_libunwind_default: Option<LlvmLibunwind>,
 161
 162     pub build: TargetSelection,
 163     pub hosts: Vec<TargetSelection>,
 164     pub targets: Vec<TargetSelection>,
 165     pub local_rebuild: bool,
 166     pub jemalloc: bool,
 167     pub control_flow_guard: bool,
 168
 169     // dist misc
 170     pub dist_sign_folder: Option<PathBuf>,
 171     pub dist_upload_addr: Option<String>,
 172     pub dist_compression_formats: Option<Vec<String>>,
 173
 174     // libstd features
 175     pub backtrace: bool, // support for RUST_BACKTRACE
 176
 177     // misc
 178     pub low_priority: bool,
 179     pub channel: String,
 180     pub description: Option<String>,
 181     pub verbose_tests: bool,
 182     pub save_toolstates: Option<PathBuf>,
 183     pub print_step_timings: bool,
 184     pub print_step_rusage: bool,
 185     pub missing_tools: bool,
 186
 187     // Fallback musl-root for all targets
 188     pub musl_root: Option<PathBuf>,
 189     pub prefix: Option<PathBuf>,
 190     pub sysconfdir: Option<PathBuf>,
 191     pub datadir: Option<PathBuf>,
 192     pub docdir: Option<PathBuf>,
 193     pub bindir: PathBuf,
 194     pub libdir: Option<PathBuf>,
 195     pub mandir: Option<PathBuf>,
 196     pub codegen_tests: bool,
 197     pub nodejs: Option<PathBuf>,
 198     pub npm: Option<PathBuf>,
 199     pub gdb: Option<PathBuf>,
 200     pub python: Option<PathBuf>,
 201     pub cargo_native_static: bool,
 202     pub configure_args: Vec<String>,
 203
 204     // These are either the stage0 downloaded binaries or the locally installed ones.
 205     pub initial_cargo: PathBuf,
 206     pub initial_rustc: PathBuf,
 207     #[cfg(not(test))]
 208     initial_rustfmt: RefCell<RustfmtState>,
 209     #[cfg(test)]
 210     pub initial_rustfmt: RefCell<RustfmtState>,
 211     pub out: PathBuf,
 212 }
 213
 214 #[derive(Clone, Debug)]
 215 pub enum RustfmtState {
 216     SystemToolchain(PathBuf),
 217     Downloaded(PathBuf),
 218     Unavailable,
 219     LazyEvaluated,
 220 }
 221
 222 impl Default for RustfmtState {
 223     fn default() -> Self {
 224         RustfmtState::LazyEvaluated
 225     }
 226 }
 227
 228 #[derive(Debug, Clone, Copy, PartialEq)]
 229 pub enum LlvmLibunwind {
 230     No,
 231     InTree,
 232     System,
 233 }
 234
 235 impl Default for LlvmLibunwind {
 236     fn default() -> Self {
 237         Self::No
 238     }
 239 }
 240
 241 impl FromStr for LlvmLibunwind {
 242     type Err = String;
 243
 244     fn from_str(value: &str) -> Result<Self, Self::Err> {
 245         match value {
 246             "no" => Ok(Self::No),
 247             "in-tree" => Ok(Self::InTree),
 248             "system" => Ok(Self::System),
 249             invalid => Err(format!("Invalid value '{}' for rust.llvm-libunwind config.", invalid)),
 250         }
 251     }
 252 }
 253
 254 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 255 pub enum SplitDebuginfo {
 256     Packed,
 257     Unpacked,
 258     Off,
 259 }
 260
 261 impl Default for SplitDebuginfo {
 262     fn default() -> Self {
 263         SplitDebuginfo::Off
 264     }
 265 }
 266
 267 impl std::str::FromStr for SplitDebuginfo {
 268     type Err = ();
 269
 270     fn from_str(s: &str) -> Result<Self, Self::Err> {
 271         match s {
 272             "packed" => Ok(SplitDebuginfo::Packed),
 273             "unpacked" => Ok(SplitDebuginfo::Unpacked),
 274             "off" => Ok(SplitDebuginfo::Off),
 275             _ => Err(()),
 276         }
 277     }
 278 }
 279
 280 impl SplitDebuginfo {
 281     /// Returns the default `-Csplit-debuginfo` value for the current target. See the comment for
 282     /// `rust.split-debuginfo` in `config.toml.example`.
 283     fn default_for_platform(target: &str) -> Self {
 284         if target.contains("apple") {
 285             SplitDebuginfo::Unpacked
 286         } else if target.contains("windows") {
 287             SplitDebuginfo::Packed
 288         } else {
 289             SplitDebuginfo::Off
 290         }
 291     }
 292 }
 293
 294 #[derive(Copy, Clone, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
 295 pub struct TargetSelection {
 296     pub triple: Interned<String>,
 297     file: Option<Interned<String>>,
 298 }
 299
 300 impl TargetSelection {
 301     pub fn from_user(selection: &str) -> Self {
 302         let path = Path::new(selection);
 303
 304         let (triple, file) = if path.exists() {
 305             let triple = path
 306                 .file_stem()
 307                 .expect("Target specification file has no file stem")
 308                 .to_str()
 309                 .expect("Target specification file stem is not UTF-8");
 310
 311             (triple, Some(selection))
 312         } else {
 313             (selection, None)
 314         };
 315
 316         let triple = INTERNER.intern_str(triple);
 317         let file = file.map(|f| INTERNER.intern_str(f));
 318
 319         Self { triple, file }
 320     }
 321
 322     pub fn rustc_target_arg(&self) -> &str {
 323         self.file.as_ref().unwrap_or(&self.triple)
 324     }
 325
 326     pub fn contains(&self, needle: &str) -> bool {
 327         self.triple.contains(needle)
 328     }
 329
 330     pub fn starts_with(&self, needle: &str) -> bool {
 331         self.triple.starts_with(needle)
 332     }
 333
 334     pub fn ends_with(&self, needle: &str) -> bool {
 335         self.triple.ends_with(needle)
 336     }
 337 }
 338
 339 impl fmt::Display for TargetSelection {
 340     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 341         write!(f, "{}", self.triple)?;
 342         if let Some(file) = self.file {
 343             write!(f, "({})", file)?;
 344         }
 345         Ok(())
 346     }
 347 }
 348
 349 impl fmt::Debug for TargetSelection {
 350     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 351         write!(f, "{}", self)
 352     }
 353 }
 354
 355 impl PartialEq<&str> for TargetSelection {
 356     fn eq(&self, other: &&str) -> bool {
 357         self.triple == *other
 358     }
 359 }
 360
 361 /// Per-target configuration stored in the global configuration structure.
 362 #[derive(Default)]
 363 #[cfg_attr(test, derive(Clone))]
 364 pub struct Target {
 365     /// Some(path to llvm-config) if using an external LLVM.
 366     pub llvm_config: Option<PathBuf>,
 367     /// Some(path to FileCheck) if one was specified.
 368     pub llvm_filecheck: Option<PathBuf>,
 369     pub llvm_libunwind: Option<LlvmLibunwind>,
 370     pub cc: Option<PathBuf>,
 371     pub cxx: Option<PathBuf>,
 372     pub ar: Option<PathBuf>,
 373     pub ranlib: Option<PathBuf>,
 374     pub default_linker: Option<PathBuf>,
 375     pub linker: Option<PathBuf>,
 376     pub ndk: Option<PathBuf>,
 377     pub sanitizers: Option<bool>,
 378     pub profiler: Option<bool>,
 379     pub crt_static: Option<bool>,
 380     pub musl_root: Option<PathBuf>,
 381     pub musl_libdir: Option<PathBuf>,
 382     pub wasi_root: Option<PathBuf>,
 383     pub qemu_rootfs: Option<PathBuf>,
 384     pub no_std: bool,
 385 }
 386
 387 impl Target {
 388     pub fn from_triple(triple: &str) -> Self {
 389         let mut target: Self = Default::default();
 390         if triple.contains("-none") || triple.contains("nvptx") {
 391             target.no_std = true;
 392         }
 393         target
 394     }
 395 }
 396 /// Structure of the `config.toml` file that configuration is read from.
 397 ///
 398 /// This structure uses `Decodable` to automatically decode a TOML configuration
 399 /// file into this format, and then this is traversed and written into the above
 400 /// `Config` structure.
 401 #[derive(Deserialize, Default)]
 402 #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 403 struct TomlConfig {
 404     changelog_seen: Option<usize>,
 405     build: Option<Build>,
 406     install: Option<Install>,
 407     llvm: Option<Llvm>,
 408     rust: Option<Rust>,
 409     target: Option<HashMap<String, TomlTarget>>,
 410     dist: Option<Dist>,
 411     profile: Option<String>,
 412 }
 413
 414 trait Merge {
 415     fn merge(&mut self, other: Self);
 416 }
 417
 418 impl Merge for TomlConfig {
 419     fn merge(
 420         &mut self,
 421         TomlConfig { build, install, llvm, rust, dist, target, profile: _, changelog_seen: _ }: Self,
 422     ) {
 423         fn do_merge<T: Merge>(x: &mut Option<T>, y: Option<T>) {
 424             if let Some(new) = y {
 425                 if let Some(original) = x {
 426                     original.merge(new);
 427                 } else {
 428                     *x = Some(new);
 429                 }
 430             }
 431         }
 432         do_merge(&mut self.build, build);
 433         do_merge(&mut self.install, install);
 434         do_merge(&mut self.llvm, llvm);
 435         do_merge(&mut self.rust, rust);
 436         do_merge(&mut self.dist, dist);
 437         assert!(target.is_none(), "merging target-specific config is not currently supported");
 438     }
 439 }
 440
 441 // We are using a decl macro instead of a derive proc macro here to reduce the compile time of
 442 // rustbuild.
 443 macro_rules! define_config {
 444     ($(#[$attr:meta])* struct $name:ident {
 445         $($field:ident: Option<$field_ty:ty> = $field_key:literal,)*
 446     }) => {
 447         $(#[$attr])*
 448         struct $name {
 449             $($field: Option<$field_ty>,)*
 450         }
 451
 452         impl Merge for $name {
 453             fn merge(&mut self, other: Self) {
 454                 $(
 455                     if !self.$field.is_some() {
 456                         self.$field = other.$field;
 457                     }
 458                 )*
 459             }
 460         }
 461
 462         // The following is a trimmed version of what serde_derive generates. All parts not relevant
 463         // for toml deserialization have been removed. This reduces the binary size and improves
 464         // compile time of rustbuild.
 465         impl<'de> Deserialize<'de> for $name {
 466             fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
 467             where
 468                 D: Deserializer<'de>,
 469             {
 470                 struct Field;
 471                 impl<'de> serde::de::Visitor<'de> for Field {
 472                     type Value = $name;
 473                     fn expecting(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
 474                         f.write_str(concat!("struct ", stringify!($name)))
 475                     }
 476
 477                     #[inline]
 478                     fn visit_map<A>(self, mut map: A) -> Result<Self::Value, A::Error>
 479                     where
 480                         A: serde::de::MapAccess<'de>,
 481                     {
 482                         $(let mut $field: Option<$field_ty> = None;)*
 483                         while let Some(key) =
 484                             match serde::de::MapAccess::next_key::<String>(&mut map) {
 485                                 Ok(val) => val,
 486                                 Err(err) => {
 487                                     return Err(err);
 488                                 }
 489                             }
 490                         {
 491                             match &*key {
 492                                 $($field_key => {
 493                                     if $field.is_some() {
 494                                         return Err(<A::Error as serde::de::Error>::duplicate_field(
 495                                             $field_key,
 496                                         ));
 497                                     }
 498                                     $field = match serde::de::MapAccess::next_value::<$field_ty>(
 499                                         &mut map,
 500                                     ) {
 501                                         Ok(val) => Some(val),
 502                                         Err(err) => {
 503                                             return Err(err);
 504                                         }
 505                                     };
 506                                 })*
 507                                 key => {
 508                                     return Err(serde::de::Error::unknown_field(key, FIELDS));
 509                                 }
 510                             }
 511                         }
 512                         Ok($name { $($field),* })
 513                     }
 514                 }
 515                 const FIELDS: &'static [&'static str] = &[
 516                     $($field_key,)*
 517                 ];
 518                 Deserializer::deserialize_struct(
 519                     deserializer,
 520                     stringify!($name),
 521                     FIELDS,
 522                     Field,
 523                 )
 524             }
 525         }
 526     }
 527 }
 528
 529 define_config! {
 530     /// TOML representation of various global build decisions.
 531     #[derive(Default)]
 532     struct Build {
 533         build: Option<String> = "build",
 534         host: Option<Vec<String>> = "host",
 535         target: Option<Vec<String>> = "target",
 536         build_dir: Option<String> = "build-dir",
 537         cargo: Option<String> = "cargo",
 538         rustc: Option<String> = "rustc",
 539         rustfmt: Option<PathBuf> = "rustfmt",
 540         docs: Option<bool> = "docs",
 541         compiler_docs: Option<bool> = "compiler-docs",
 542         docs_minification: Option<bool> = "docs-minification",
 543         submodules: Option<bool> = "submodules",
 544         gdb: Option<String> = "gdb",
 545         nodejs: Option<String> = "nodejs",
 546         npm: Option<String> = "npm",
 547         python: Option<String> = "python",
 548         locked_deps: Option<bool> = "locked-deps",
 549         vendor: Option<bool> = "vendor",
 550         full_bootstrap: Option<bool> = "full-bootstrap",
 551         extended: Option<bool> = "extended",
 552         tools: Option<HashSet<String>> = "tools",
 553         verbose: Option<usize> = "verbose",
 554         sanitizers: Option<bool> = "sanitizers",
 555         profiler: Option<bool> = "profiler",
 556         cargo_native_static: Option<bool> = "cargo-native-static",
 557         low_priority: Option<bool> = "low-priority",
 558         configure_args: Option<Vec<String>> = "configure-args",
 559         local_rebuild: Option<bool> = "local-rebuild",
 560         print_step_timings: Option<bool> = "print-step-timings",
 561         print_step_rusage: Option<bool> = "print-step-rusage",
 562         check_stage: Option<u32> = "check-stage",
 563         doc_stage: Option<u32> = "doc-stage",
 564         build_stage: Option<u32> = "build-stage",
 565         test_stage: Option<u32> = "test-stage",
 566         install_stage: Option<u32> = "install-stage",
 567         dist_stage: Option<u32> = "dist-stage",
 568         bench_stage: Option<u32> = "bench-stage",
 569         patch_binaries_for_nix: Option<bool> = "patch-binaries-for-nix",
 570         metrics: Option<bool> = "metrics",
 571     }
 572 }
 573
 574 define_config! {
 575     /// TOML representation of various global install decisions.
 576     struct Install {
 577         prefix: Option<String> = "prefix",
 578         sysconfdir: Option<String> = "sysconfdir",
 579         docdir: Option<String> = "docdir",
 580         bindir: Option<String> = "bindir",
 581         libdir: Option<String> = "libdir",
 582         mandir: Option<String> = "mandir",
 583         datadir: Option<String> = "datadir",
 584     }
 585 }
 586
 587 define_config! {
 588     /// TOML representation of how the LLVM build is configured.
 589     struct Llvm {
 590         skip_rebuild: Option<bool> = "skip-rebuild",
 591         optimize: Option<bool> = "optimize",
 592         thin_lto: Option<bool> = "thin-lto",
 593         release_debuginfo: Option<bool> = "release-debuginfo",
 594         assertions: Option<bool> = "assertions",
 595         tests: Option<bool> = "tests",
 596         plugins: Option<bool> = "plugins",
 597         ccache: Option<StringOrBool> = "ccache",
 598         version_check: Option<bool> = "version-check",
 599         static_libstdcpp: Option<bool> = "static-libstdcpp",
 600         ninja: Option<bool> = "ninja",
 601         targets: Option<String> = "targets",
 602         experimental_targets: Option<String> = "experimental-targets",
 603         link_jobs: Option<u32> = "link-jobs",
 604         link_shared: Option<bool> = "link-shared",
 605         version_suffix: Option<String> = "version-suffix",
 606         clang_cl: Option<String> = "clang-cl",
 607         cflags: Option<String> = "cflags",
 608         cxxflags: Option<String> = "cxxflags",
 609         ldflags: Option<String> = "ldflags",
 610         use_libcxx: Option<bool> = "use-libcxx",
 611         use_linker: Option<String> = "use-linker",
 612         allow_old_toolchain: Option<bool> = "allow-old-toolchain",
 613         polly: Option<bool> = "polly",
 614         clang: Option<bool> = "clang",
 615         download_ci_llvm: Option<StringOrBool> = "download-ci-llvm",
 616         build_config: Option<HashMap<String, String>> = "build-config",
 617     }
 618 }
 619
 620 define_config! {
 621     struct Dist {
 622         sign_folder: Option<String> = "sign-folder",
 623         gpg_password_file: Option<String> = "gpg-password-file",
 624         upload_addr: Option<String> = "upload-addr",
 625         src_tarball: Option<bool> = "src-tarball",
 626         missing_tools: Option<bool> = "missing-tools",
 627         compression_formats: Option<Vec<String>> = "compression-formats",
 628     }
 629 }
 630
 631 #[derive(Deserialize)]
 632 #[serde(untagged)]
 633 enum StringOrBool {
 634     String(String),
 635     Bool(bool),
 636 }
 637
 638 impl Default for StringOrBool {
 639     fn default() -> StringOrBool {
 640         StringOrBool::Bool(false)
 641     }
 642 }
 643
 644 define_config! {
 645     /// TOML representation of how the Rust build is configured.
 646     struct Rust {
 647         optimize: Option<bool> = "optimize",
 648         debug: Option<bool> = "debug",
 649         codegen_units: Option<u32> = "codegen-units",
 650         codegen_units_std: Option<u32> = "codegen-units-std",
 651         debug_assertions: Option<bool> = "debug-assertions",
 652         debug_assertions_std: Option<bool> = "debug-assertions-std",
 653         overflow_checks: Option<bool> = "overflow-checks",
 654         overflow_checks_std: Option<bool> = "overflow-checks-std",
 655         debug_logging: Option<bool> = "debug-logging",
 656         debuginfo_level: Option<u32> = "debuginfo-level",
 657         debuginfo_level_rustc: Option<u32> = "debuginfo-level-rustc",
 658         debuginfo_level_std: Option<u32> = "debuginfo-level-std",
 659         debuginfo_level_tools: Option<u32> = "debuginfo-level-tools",
 660         debuginfo_level_tests: Option<u32> = "debuginfo-level-tests",
 661         split_debuginfo: Option<String> = "split-debuginfo",
 662         run_dsymutil: Option<bool> = "run-dsymutil",
 663         backtrace: Option<bool> = "backtrace",
 664         incremental: Option<bool> = "incremental",
 665         parallel_compiler: Option<bool> = "parallel-compiler",
 666         default_linker: Option<String> = "default-linker",
 667         channel: Option<String> = "channel",
 668         description: Option<String> = "description",
 669         musl_root: Option<String> = "musl-root",
 670         rpath: Option<bool> = "rpath",
 671         verbose_tests: Option<bool> = "verbose-tests",
 672         optimize_tests: Option<bool> = "optimize-tests",
 673         codegen_tests: Option<bool> = "codegen-tests",
 674         ignore_git: Option<bool> = "ignore-git",
 675         dist_src: Option<bool> = "dist-src",
 676         save_toolstates: Option<String> = "save-toolstates",
 677         codegen_backends: Option<Vec<String>> = "codegen-backends",
 678         lld: Option<bool> = "lld",
 679         use_lld: Option<bool> = "use-lld",
 680         llvm_tools: Option<bool> = "llvm-tools",
 681         deny_warnings: Option<bool> = "deny-warnings",
 682         backtrace_on_ice: Option<bool> = "backtrace-on-ice",
 683         verify_llvm_ir: Option<bool> = "verify-llvm-ir",
 684         thin_lto_import_instr_limit: Option<u32> = "thin-lto-import-instr-limit",
 685         remap_debuginfo: Option<bool> = "remap-debuginfo",
 686         jemalloc: Option<bool> = "jemalloc",
 687         test_compare_mode: Option<bool> = "test-compare-mode",
 688         llvm_libunwind: Option<String> = "llvm-libunwind",
 689         control_flow_guard: Option<bool> = "control-flow-guard",
 690         new_symbol_mangling: Option<bool> = "new-symbol-mangling",
 691         profile_generate: Option<String> = "profile-generate",
 692         profile_use: Option<String> = "profile-use",
 693         // ignored; this is set from an env var set by bootstrap.py
 694         download_rustc: Option<StringOrBool> = "download-rustc",
 695     }
 696 }
 697
 698 define_config! {
 699     /// TOML representation of how each build target is configured.
 700     struct TomlTarget {
 701         cc: Option<String> = "cc",
 702         cxx: Option<String> = "cxx",
 703         ar: Option<String> = "ar",
 704         ranlib: Option<String> = "ranlib",
 705         default_linker: Option<PathBuf> = "default-linker",
 706         linker: Option<String> = "linker",
 707         llvm_config: Option<String> = "llvm-config",
 708         llvm_filecheck: Option<String> = "llvm-filecheck",
 709         llvm_libunwind: Option<String> = "llvm-libunwind",
 710         android_ndk: Option<String> = "android-ndk",
 711         sanitizers: Option<bool> = "sanitizers",
 712         profiler: Option<bool> = "profiler",
 713         crt_static: Option<bool> = "crt-static",
 714         musl_root: Option<String> = "musl-root",
 715         musl_libdir: Option<String> = "musl-libdir",
 716         wasi_root: Option<String> = "wasi-root",
 717         qemu_rootfs: Option<String> = "qemu-rootfs",
 718         no_std: Option<bool> = "no-std",
 719     }
 720 }
 721
 722 impl Config {
 723     pub fn default_opts() -> Config {
 724         let mut config = Config::default();
 725         config.llvm_optimize = true;
 726         config.ninja_in_file = true;
 727         config.llvm_version_check = true;
 728         config.llvm_static_stdcpp = true;
 729         config.backtrace = true;
 730         config.rust_optimize = true;
 731         config.rust_optimize_tests = true;
 732         config.submodules = None;
 733         config.docs = true;
 734         config.docs_minification = true;
 735         config.rust_rpath = true;
 736         config.channel = "dev".to_string();
 737         config.codegen_tests = true;
 738         config.rust_dist_src = true;
 739         config.rust_codegen_backends = vec![INTERNER.intern_str("llvm")];
 740         config.deny_warnings = true;
 741         config.bindir = "bin".into();
 742
 743         // set by build.rs
 744         config.build = TargetSelection::from_user(&env!("BUILD_TRIPLE"));
 745         let manifest_dir = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
 746         // Undo `src/bootstrap`
 747         config.src = manifest_dir.parent().unwrap().parent().unwrap().to_owned();
 748         config.out = PathBuf::from("build");
 749
 750         config.initial_cargo = PathBuf::from(env!("CARGO"));
 751         config.initial_rustc = PathBuf::from(env!("RUSTC"));
 752
 753         config
 754     }
 755
 756     pub fn parse(args: &[String]) -> Config {
 757         let flags = Flags::parse(&args);
 758
 759         let mut config = Config::default_opts();
 760         config.exclude = flags.exclude.into_iter().map(|path| TaskPath::parse(path)).collect();
 761         config.include_default_paths = flags.include_default_paths;
 762         config.rustc_error_format = flags.rustc_error_format;
 763         config.json_output = flags.json_output;
 764         config.on_fail = flags.on_fail;
 765         config.jobs = flags.jobs.map(threads_from_config);
 766         config.cmd = flags.cmd;
 767         config.incremental = flags.incremental;
 768         config.dry_run = flags.dry_run;
 769         config.keep_stage = flags.keep_stage;
 770         config.keep_stage_std = flags.keep_stage_std;
 771         config.color = flags.color;
 772         if let Some(value) = flags.deny_warnings {
 773             config.deny_warnings = value;
 774         }
 775         config.llvm_profile_use = flags.llvm_profile_use;
 776         config.llvm_profile_generate = flags.llvm_profile_generate;
 777
 778         #[cfg(test)]
 779         let get_toml = |_| TomlConfig::default();
 780         #[cfg(not(test))]
 781         let get_toml = |file: &Path| {
 782             use std::process;
 783
 784             let contents =
 785                 t!(fs::read_to_string(file), format!("config file {} not found", file.display()));
 786             // Deserialize to Value and then TomlConfig to prevent the Deserialize impl of
 787             // TomlConfig and sub types to be monomorphized 5x by toml.
 788             match toml::from_str(&contents)
 789                 .and_then(|table: toml::Value| TomlConfig::deserialize(table))
 790             {
 791                 Ok(table) => table,
 792                 Err(err) => {
 793                     eprintln!("failed to parse TOML configuration '{}': {}", file.display(), err);
 794                     process::exit(2);
 795                 }
 796             }
 797         };
 798
 799         // Read from `--config`, then `RUST_BOOTSTRAP_CONFIG`, then `./config.toml`, then `config.toml` in the root directory.
 800         let toml_path = flags
 801             .config
 802             .clone()
 803             .or_else(|| env::var_os("RUST_BOOTSTRAP_CONFIG").map(PathBuf::from));
 804         let using_default_path = toml_path.is_none();
 805         let mut toml_path = toml_path.unwrap_or_else(|| PathBuf::from("config.toml"));
 806         if using_default_path && !toml_path.exists() {
 807             toml_path = config.src.join(toml_path);
 808         }
 809
 810         // Give a hard error if `--config` or `RUST_BOOTSTRAP_CONFIG` are set to a missing path,
 811         // but not if `config.toml` hasn't been created.
 812         let mut toml = if !using_default_path || toml_path.exists() {
 813             get_toml(&toml_path)
 814         } else {
 815             TomlConfig::default()
 816         };
 817
 818         if let Some(include) = &toml.profile {
 819             let mut include_path = config.src.clone();
 820             include_path.push("src");
 821             include_path.push("bootstrap");
 822             include_path.push("defaults");
 823             include_path.push(format!("config.{}.toml", include));
 824             let included_toml = get_toml(&include_path);
 825             toml.merge(included_toml);
 826         }
 827
 828         config.changelog_seen = toml.changelog_seen;
 829         config.config = toml_path;
 830
 831         let build = toml.build.unwrap_or_default();
 832
 833         set(&mut config.initial_rustc, build.rustc.map(PathBuf::from));
 834         set(&mut config.out, build.build_dir.map(PathBuf::from));
 835         // NOTE: Bootstrap spawns various commands with different working directories.
 836         // To avoid writing to random places on the file system, `config.out` needs to be an absolute path.
 837         if !config.out.is_absolute() {
 838             // `canonicalize` requires the path to already exist. Use our vendored copy of `absolute` instead.
 839             config.out = crate::util::absolute(&config.out);
 840         }
 841
 842         if config.dry_run {
 843             let dir = config.out.join("tmp-dry-run");
 844             t!(fs::create_dir_all(&dir));
 845             config.out = dir;
 846         }
 847
 848         config.hosts = if let Some(arg_host) = flags.host {
 849             arg_host
 850         } else if let Some(file_host) = build.host {
 851             file_host.iter().map(|h| TargetSelection::from_user(h)).collect()
 852         } else {
 853             vec![config.build]
 854         };
 855         config.targets = if let Some(arg_target) = flags.target {
 856             arg_target
 857         } else if let Some(file_target) = build.target {
 858             file_target.iter().map(|h| TargetSelection::from_user(h)).collect()
 859         } else {
 860             // If target is *not* configured, then default to the host
 861             // toolchains.
 862             config.hosts.clone()
 863         };
 864
 865         config.nodejs = build.nodejs.map(PathBuf::from);
 866         config.npm = build.npm.map(PathBuf::from);
 867         config.gdb = build.gdb.map(PathBuf::from);
 868         config.python = build.python.map(PathBuf::from);
 869         config.submodules = build.submodules;
 870         set(&mut config.low_priority, build.low_priority);
 871         set(&mut config.compiler_docs, build.compiler_docs);
 872         set(&mut config.docs_minification, build.docs_minification);
 873         set(&mut config.docs, build.docs);
 874         set(&mut config.locked_deps, build.locked_deps);
 875         set(&mut config.vendor, build.vendor);
 876         set(&mut config.full_bootstrap, build.full_bootstrap);
 877         set(&mut config.extended, build.extended);
 878         config.tools = build.tools;
 879         set(&mut config.verbose, build.verbose);
 880         set(&mut config.sanitizers, build.sanitizers);
 881         set(&mut config.profiler, build.profiler);
 882         set(&mut config.cargo_native_static, build.cargo_native_static);
 883         set(&mut config.configure_args, build.configure_args);
 884         set(&mut config.local_rebuild, build.local_rebuild);
 885         set(&mut config.print_step_timings, build.print_step_timings);
 886         set(&mut config.print_step_rusage, build.print_step_rusage);
 887         set(&mut config.patch_binaries_for_nix, build.patch_binaries_for_nix);
 888
 889         config.verbose = cmp::max(config.verbose, flags.verbose);
 890
 891         if let Some(install) = toml.install {
 892             config.prefix = install.prefix.map(PathBuf::from);
 893             config.sysconfdir = install.sysconfdir.map(PathBuf::from);
 894             config.datadir = install.datadir.map(PathBuf::from);
 895             config.docdir = install.docdir.map(PathBuf::from);
 896             set(&mut config.bindir, install.bindir.map(PathBuf::from));
 897             config.libdir = install.libdir.map(PathBuf::from);
 898             config.mandir = install.mandir.map(PathBuf::from);
 899         }
 900
 901         // We want the llvm-skip-rebuild flag to take precedence over the
 902         // skip-rebuild config.toml option so we store it separately
 903         // so that we can infer the right value
 904         let mut llvm_skip_rebuild = flags.llvm_skip_rebuild;
 905
 906         // Store off these values as options because if they're not provided
 907         // we'll infer default values for them later
 908         let mut llvm_assertions = None;
 909         let mut llvm_tests = None;
 910         let mut llvm_plugins = None;
 911         let mut debug = None;
 912         let mut debug_assertions = None;
 913         let mut debug_assertions_std = None;
 914         let mut overflow_checks = None;
 915         let mut overflow_checks_std = None;
 916         let mut debug_logging = None;
 917         let mut debuginfo_level = None;
 918         let mut debuginfo_level_rustc = None;
 919         let mut debuginfo_level_std = None;
 920         let mut debuginfo_level_tools = None;
 921         let mut debuginfo_level_tests = None;
 922         let mut optimize = None;
 923         let mut ignore_git = None;
 924
 925         if let Some(llvm) = toml.llvm {
 926             match llvm.ccache {
 927                 Some(StringOrBool::String(ref s)) => config.ccache = Some(s.to_string()),
 928                 Some(StringOrBool::Bool(true)) => {
 929                     config.ccache = Some("ccache".to_string());
 930                 }
 931                 Some(StringOrBool::Bool(false)) | None => {}
 932             }
 933             set(&mut config.ninja_in_file, llvm.ninja);
 934             llvm_assertions = llvm.assertions;
 935             llvm_tests = llvm.tests;
 936             llvm_plugins = llvm.plugins;
 937             llvm_skip_rebuild = llvm_skip_rebuild.or(llvm.skip_rebuild);
 938             set(&mut config.llvm_optimize, llvm.optimize);
 939             set(&mut config.llvm_thin_lto, llvm.thin_lto);
 940             set(&mut config.llvm_release_debuginfo, llvm.release_debuginfo);
 941             set(&mut config.llvm_version_check, llvm.version_check);
 942             set(&mut config.llvm_static_stdcpp, llvm.static_libstdcpp);
 943             if let Some(v) = llvm.link_shared {
 944                 config.llvm_link_shared.set(Some(v));
 945             }
 946             config.llvm_targets = llvm.targets.clone();
 947             config.llvm_experimental_targets = llvm.experimental_targets.clone();
 948             config.llvm_link_jobs = llvm.link_jobs;
 949             config.llvm_version_suffix = llvm.version_suffix.clone();
 950             config.llvm_clang_cl = llvm.clang_cl.clone();
 951
 952             config.llvm_cflags = llvm.cflags.clone();
 953             config.llvm_cxxflags = llvm.cxxflags.clone();
 954             config.llvm_ldflags = llvm.ldflags.clone();
 955             set(&mut config.llvm_use_libcxx, llvm.use_libcxx);
 956             config.llvm_use_linker = llvm.use_linker.clone();
 957             config.llvm_allow_old_toolchain = llvm.allow_old_toolchain.unwrap_or(false);
 958             config.llvm_polly = llvm.polly.unwrap_or(false);
 959             config.llvm_clang = llvm.clang.unwrap_or(false);
 960             config.llvm_build_config = llvm.build_config.clone().unwrap_or(Default::default());
 961             config.llvm_from_ci = match llvm.download_ci_llvm {
 962                 Some(StringOrBool::String(s)) => {
 963                     assert!(s == "if-available", "unknown option `{}` for download-ci-llvm", s);
 964                     // This is currently all tier 1 targets and tier 2 targets with host tools
 965                     // (since others may not have CI artifacts)
 966                     // https://doc.rust-lang.org/rustc/platform-support.html#tier-1
 967                     // FIXME: this is duplicated in bootstrap.py
 968                     let supported_platforms = [
 969                         // tier 1
 970                         "aarch64-unknown-linux-gnu",
 971                         "i686-pc-windows-gnu",
 972                         "i686-pc-windows-msvc",
 973                         "i686-unknown-linux-gnu",
 974                         "x86_64-unknown-linux-gnu",
 975                         "x86_64-apple-darwin",
 976                         "x86_64-pc-windows-gnu",
 977                         "x86_64-pc-windows-msvc",
 978                         // tier 2 with host tools
 979                         "aarch64-apple-darwin",
 980                         "aarch64-pc-windows-msvc",
 981                         "aarch64-unknown-linux-musl",
 982                         "arm-unknown-linux-gnueabi",
 983                         "arm-unknown-linux-gnueabihf",
 984                         "armv7-unknown-linux-gnueabihf",
 985                         "mips-unknown-linux-gnu",
 986                         "mips64-unknown-linux-gnuabi64",
 987                         "mips64el-unknown-linux-gnuabi64",
 988                         "mipsel-unknown-linux-gnu",
 989                         "powerpc-unknown-linux-gnu",
 990                         "powerpc64-unknown-linux-gnu",
 991                         "powerpc64le-unknown-linux-gnu",
 992                         "riscv64gc-unknown-linux-gnu",
 993                         "s390x-unknown-linux-gnu",
 994                         "x86_64-unknown-freebsd",
 995                         "x86_64-unknown-illumos",
 996                         "x86_64-unknown-linux-musl",
 997                         "x86_64-unknown-netbsd",
 998                     ];
 999                     supported_platforms.contains(&&*config.build.triple)
1000                 }
1001                 Some(StringOrBool::Bool(b)) => b,
1002                 None => false,
1003             };
1004
1005             if config.llvm_from_ci {
1006                 // None of the LLVM options, except assertions, are supported
1007                 // when using downloaded LLVM. We could just ignore these but
1008                 // that's potentially confusing, so force them to not be
1009                 // explicitly set. The defaults and CI defaults don't
1010                 // necessarily match but forcing people to match (somewhat
1011                 // arbitrary) CI configuration locally seems bad/hard.
1012                 check_ci_llvm!(llvm.optimize);
1013                 check_ci_llvm!(llvm.thin_lto);
1014                 check_ci_llvm!(llvm.release_debuginfo);
1015                 // CI-built LLVM can be either dynamic or static. We won't know until we download it.
1016                 check_ci_llvm!(llvm.link_shared);
1017                 check_ci_llvm!(llvm.static_libstdcpp);
1018                 check_ci_llvm!(llvm.targets);
1019                 check_ci_llvm!(llvm.experimental_targets);
1020                 check_ci_llvm!(llvm.link_jobs);
1021                 check_ci_llvm!(llvm.clang_cl);
1022                 check_ci_llvm!(llvm.version_suffix);
1023                 check_ci_llvm!(llvm.cflags);
1024                 check_ci_llvm!(llvm.cxxflags);
1025                 check_ci_llvm!(llvm.ldflags);
1026                 check_ci_llvm!(llvm.use_libcxx);
1027                 check_ci_llvm!(llvm.use_linker);
1028                 check_ci_llvm!(llvm.allow_old_toolchain);
1029                 check_ci_llvm!(llvm.polly);
1030                 check_ci_llvm!(llvm.clang);
1031                 check_ci_llvm!(llvm.build_config);
1032                 check_ci_llvm!(llvm.plugins);
1033             }
1034
1035             // NOTE: can never be hit when downloading from CI, since we call `check_ci_llvm!(thin_lto)` above.
1036             if config.llvm_thin_lto && llvm.link_shared.is_none() {
1037                 // If we're building with ThinLTO on, by default we want to link
1038                 // to LLVM shared, to avoid re-doing ThinLTO (which happens in
1039                 // the link step) with each stage.
1040                 config.llvm_link_shared.set(Some(true));
1041             }
1042         }
1043
1044         if let Some(rust) = toml.rust {
1045             debug = rust.debug;
1046             debug_assertions = rust.debug_assertions;
1047             debug_assertions_std = rust.debug_assertions_std;
1048             overflow_checks = rust.overflow_checks;
1049             overflow_checks_std = rust.overflow_checks_std;
1050             debug_logging = rust.debug_logging;
1051             debuginfo_level = rust.debuginfo_level;
1052             debuginfo_level_rustc = rust.debuginfo_level_rustc;
1053             debuginfo_level_std = rust.debuginfo_level_std;
1054             debuginfo_level_tools = rust.debuginfo_level_tools;
1055             debuginfo_level_tests = rust.debuginfo_level_tests;
1056             config.rust_split_debuginfo = rust
1057                 .split_debuginfo
1058                 .as_deref()
1059                 .map(SplitDebuginfo::from_str)
1060                 .map(|v| v.expect("invalid value for rust.split_debuginfo"))
1061                 .unwrap_or(SplitDebuginfo::default_for_platform(&config.build.triple));
1062             optimize = rust.optimize;
1063             ignore_git = rust.ignore_git;
1064             config.rust_new_symbol_mangling = rust.new_symbol_mangling;
1065             set(&mut config.rust_optimize_tests, rust.optimize_tests);
1066             set(&mut config.codegen_tests, rust.codegen_tests);
1067             set(&mut config.rust_rpath, rust.rpath);
1068             set(&mut config.jemalloc, rust.jemalloc);
1069             set(&mut config.test_compare_mode, rust.test_compare_mode);
1070             set(&mut config.backtrace, rust.backtrace);
1071             set(&mut config.channel, rust.channel);
1072             config.description = rust.description;
1073             set(&mut config.rust_dist_src, rust.dist_src);
1074             set(&mut config.verbose_tests, rust.verbose_tests);
1075             // in the case "false" is set explicitly, do not overwrite the command line args
1076             if let Some(true) = rust.incremental {
1077                 config.incremental = true;
1078             }
1079             set(&mut config.use_lld, rust.use_lld);
1080             set(&mut config.lld_enabled, rust.lld);
1081             set(&mut config.llvm_tools_enabled, rust.llvm_tools);
1082             config.rustc_parallel = rust.parallel_compiler.unwrap_or(false);
1083             config.rustc_default_linker = rust.default_linker;
1084             config.musl_root = rust.musl_root.map(PathBuf::from);
1085             config.save_toolstates = rust.save_toolstates.map(PathBuf::from);
1086             set(&mut config.deny_warnings, flags.deny_warnings.or(rust.deny_warnings));
1087             set(&mut config.backtrace_on_ice, rust.backtrace_on_ice);
1088             set(&mut config.rust_verify_llvm_ir, rust.verify_llvm_ir);
1089             config.rust_thin_lto_import_instr_limit = rust.thin_lto_import_instr_limit;
1090             set(&mut config.rust_remap_debuginfo, rust.remap_debuginfo);
1091             set(&mut config.control_flow_guard, rust.control_flow_guard);
1092             config.llvm_libunwind_default = rust
1093                 .llvm_libunwind
1094                 .map(|v| v.parse().expect("failed to parse rust.llvm-libunwind"));
1095
1096             if let Some(ref backends) = rust.codegen_backends {
1097                 config.rust_codegen_backends =
1098                     backends.iter().map(|s| INTERNER.intern_str(s)).collect();
1099             }
1100
1101             config.rust_codegen_units = rust.codegen_units.map(threads_from_config);
1102             config.rust_codegen_units_std = rust.codegen_units_std.map(threads_from_config);
1103             config.rust_profile_use = flags.rust_profile_use.or(rust.profile_use);
1104             config.rust_profile_generate = flags.rust_profile_generate.or(rust.profile_generate);
1105             config.download_rustc_commit =
1106                 download_ci_rustc_commit(rust.download_rustc, config.verbose > 0);
1107         } else {
1108             config.rust_profile_use = flags.rust_profile_use;
1109             config.rust_profile_generate = flags.rust_profile_generate;
1110         }
1111
1112         if let Some(t) = toml.target {
1113             for (triple, cfg) in t {
1114                 let mut target = Target::from_triple(&triple);
1115
1116                 if let Some(ref s) = cfg.llvm_config {
1117                     target.llvm_config = Some(config.src.join(s));
1118                 }
1119                 if let Some(ref s) = cfg.llvm_filecheck {
1120                     target.llvm_filecheck = Some(config.src.join(s));
1121                 }
1122                 target.llvm_libunwind = cfg
1123                     .llvm_libunwind
1124                     .as_ref()
1125                     .map(|v| v.parse().expect("failed to parse rust.llvm-libunwind"));
1126                 if let Some(ref s) = cfg.android_ndk {
1127                     target.ndk = Some(config.src.join(s));
1128                 }
1129                 if let Some(s) = cfg.no_std {
1130                     target.no_std = s;
1131                 }
1132                 target.cc = cfg.cc.map(PathBuf::from);
1133                 target.cxx = cfg.cxx.map(PathBuf::from);
1134                 target.ar = cfg.ar.map(PathBuf::from);
1135                 target.ranlib = cfg.ranlib.map(PathBuf::from);
1136                 target.linker = cfg.linker.map(PathBuf::from);
1137                 target.crt_static = cfg.crt_static;
1138                 target.musl_root = cfg.musl_root.map(PathBuf::from);
1139                 target.musl_libdir = cfg.musl_libdir.map(PathBuf::from);
1140                 target.wasi_root = cfg.wasi_root.map(PathBuf::from);
1141                 target.qemu_rootfs = cfg.qemu_rootfs.map(PathBuf::from);
1142                 target.sanitizers = cfg.sanitizers;
1143                 target.profiler = cfg.profiler;
1144
1145                 config.target_config.insert(TargetSelection::from_user(&triple), target);
1146             }
1147         }
1148
1149         if config.llvm_from_ci {
1150             let triple = &config.build.triple;
1151             let mut build_target = config
1152                 .target_config
1153                 .entry(config.build)
1154                 .or_insert_with(|| Target::from_triple(&triple));
1155
1156             check_ci_llvm!(build_target.llvm_config);
1157             check_ci_llvm!(build_target.llvm_filecheck);
1158             let ci_llvm_bin = config.out.join(&*config.build.triple).join("ci-llvm/bin");
1159             build_target.llvm_config = Some(ci_llvm_bin.join(exe("llvm-config", config.build)));
1160             build_target.llvm_filecheck = Some(ci_llvm_bin.join(exe("FileCheck", config.build)));
1161         }
1162
1163         if let Some(t) = toml.dist {
1164             config.dist_sign_folder = t.sign_folder.map(PathBuf::from);
1165             config.dist_upload_addr = t.upload_addr;
1166             config.dist_compression_formats = t.compression_formats;
1167             set(&mut config.rust_dist_src, t.src_tarball);
1168             set(&mut config.missing_tools, t.missing_tools);
1169         }
1170
1171         if let Some(r) = build.rustfmt {
1172             *config.initial_rustfmt.borrow_mut() = if r.exists() {
1173                 RustfmtState::SystemToolchain(r)
1174             } else {
1175                 RustfmtState::Unavailable
1176             };
1177         } else {
1178             // If using a system toolchain for bootstrapping, see if that has rustfmt available.
1179             let host = config.build;
1180             let rustfmt_path = config.initial_rustc.with_file_name(exe("rustfmt", host));
1181             let bin_root = config.out.join(host.triple).join("stage0");
1182             if !rustfmt_path.starts_with(&bin_root) {
1183                 // Using a system-provided toolchain; we shouldn't download rustfmt.
1184                 *config.initial_rustfmt.borrow_mut() = RustfmtState::SystemToolchain(rustfmt_path);
1185             }
1186         }
1187
1188         // Now that we've reached the end of our configuration, infer the
1189         // default values for all options that we haven't otherwise stored yet.
1190
1191         config.llvm_skip_rebuild = llvm_skip_rebuild.unwrap_or(false);
1192         config.llvm_assertions = llvm_assertions.unwrap_or(false);
1193         config.llvm_tests = llvm_tests.unwrap_or(false);
1194         config.llvm_plugins = llvm_plugins.unwrap_or(false);
1195         config.rust_optimize = optimize.unwrap_or(true);
1196
1197         let default = debug == Some(true);
1198         config.rust_debug_assertions = debug_assertions.unwrap_or(default);
1199         config.rust_debug_assertions_std =
1200             debug_assertions_std.unwrap_or(config.rust_debug_assertions);
1201         config.rust_overflow_checks = overflow_checks.unwrap_or(default);
1202         config.rust_overflow_checks_std =
1203             overflow_checks_std.unwrap_or(config.rust_overflow_checks);
1204
1205         config.rust_debug_logging = debug_logging.unwrap_or(config.rust_debug_assertions);
1206
1207         let with_defaults = |debuginfo_level_specific: Option<u32>| {
1208             debuginfo_level_specific.or(debuginfo_level).unwrap_or(if debug == Some(true) {
1209                 1
1210             } else {
1211                 0
1212             })
1213         };
1214         config.rust_debuginfo_level_rustc = with_defaults(debuginfo_level_rustc);
1215         config.rust_debuginfo_level_std = with_defaults(debuginfo_level_std);
1216         config.rust_debuginfo_level_tools = with_defaults(debuginfo_level_tools);
1217         config.rust_debuginfo_level_tests = debuginfo_level_tests.unwrap_or(0);
1218
1219         let default = config.channel == "dev";
1220         config.ignore_git = ignore_git.unwrap_or(default);
1221
1222         let download_rustc = config.download_rustc_commit.is_some();
1223         // See https://github.com/rust-lang/compiler-team/issues/326
1224         config.stage = match config.cmd {
1225             Subcommand::Check { .. } => flags.stage.or(build.check_stage).unwrap_or(0),
1226             // `download-rustc` only has a speed-up for stage2 builds. Default to stage2 unless explicitly overridden.
1227             Subcommand::Doc { .. } => {
1228                 flags.stage.or(build.doc_stage).unwrap_or(if download_rustc { 2 } else { 0 })
1229             }
1230             Subcommand::Build { .. } => {
1231                 flags.stage.or(build.build_stage).unwrap_or(if download_rustc { 2 } else { 1 })
1232             }
1233             Subcommand::Test { .. } => {
1234                 flags.stage.or(build.test_stage).unwrap_or(if download_rustc { 2 } else { 1 })
1235             }
1236             Subcommand::Bench { .. } => flags.stage.or(build.bench_stage).unwrap_or(2),
1237             Subcommand::Dist { .. } => flags.stage.or(build.dist_stage).unwrap_or(2),
1238             Subcommand::Install { .. } => flags.stage.or(build.install_stage).unwrap_or(2),
1239             // These are all bootstrap tools, which don't depend on the compiler.
1240             // The stage we pass shouldn't matter, but use 0 just in case.
1241             Subcommand::Clean { .. }
1242             | Subcommand::Clippy { .. }
1243             | Subcommand::Fix { .. }
1244             | Subcommand::Run { .. }
1245             | Subcommand::Setup { .. }
1246             | Subcommand::Format { .. } => flags.stage.unwrap_or(0),
1247         };
1248
1249         // CI should always run stage 2 builds, unless it specifically states otherwise
1250         #[cfg(not(test))]
1251         if flags.stage.is_none() && crate::CiEnv::current() != crate::CiEnv::None {
1252             match config.cmd {
1253                 Subcommand::Test { .. }
1254                 | Subcommand::Doc { .. }
1255                 | Subcommand::Build { .. }
1256                 | Subcommand::Bench { .. }
1257                 | Subcommand::Dist { .. }
1258                 | Subcommand::Install { .. } => {
1259                     assert_eq!(
1260                         config.stage, 2,
1261                         "x.py should be run with `--stage 2` on CI, but was run with `--stage {}`",
1262                         config.stage,
1263                     );
1264                 }
1265                 Subcommand::Clean { .. }
1266                 | Subcommand::Check { .. }
1267                 | Subcommand::Clippy { .. }
1268                 | Subcommand::Fix { .. }
1269                 | Subcommand::Run { .. }
1270                 | Subcommand::Setup { .. }
1271                 | Subcommand::Format { .. } => {}
1272             }
1273         }
1274
1275         config
1276     }
1277
1278     /// Try to find the relative path of `bindir`, otherwise return it in full.
1279     pub fn bindir_relative(&self) -> &Path {
1280         let bindir = &self.bindir;
1281         if bindir.is_absolute() {
1282             // Try to make it relative to the prefix.
1283             if let Some(prefix) = &self.prefix {
1284                 if let Ok(stripped) = bindir.strip_prefix(prefix) {
1285                     return stripped;
1286                 }
1287             }
1288         }
1289         bindir
1290     }
1291
1292     /// Try to find the relative path of `libdir`.
1293     pub fn libdir_relative(&self) -> Option<&Path> {
1294         let libdir = self.libdir.as_ref()?;
1295         if libdir.is_relative() {
1296             Some(libdir)
1297         } else {
1298             // Try to make it relative to the prefix.
1299             libdir.strip_prefix(self.prefix.as_ref()?).ok()
1300         }
1301     }
1302
1303     /// The absolute path to the downloaded LLVM artifacts.
1304     pub(crate) fn ci_llvm_root(&self) -> PathBuf {
1305         assert!(self.llvm_from_ci);
1306         self.out.join(&*self.build.triple).join("ci-llvm")
1307     }
1308
1309     /// Determine whether llvm should be linked dynamically.
1310     ///
1311     /// If `false`, llvm should be linked statically.
1312     /// This is computed on demand since LLVM might have to first be downloaded from CI.
1313     pub(crate) fn llvm_link_shared(builder: &Builder<'_>) -> bool {
1314         let mut opt = builder.config.llvm_link_shared.get();
1315         if opt.is_none() && builder.config.dry_run {
1316             // just assume static for now - dynamic linking isn't supported on all platforms
1317             return false;
1318         }
1319
1320         let llvm_link_shared = *opt.get_or_insert_with(|| {
1321             if builder.config.llvm_from_ci {
1322                 crate::native::maybe_download_ci_llvm(builder);
1323                 let ci_llvm = builder.config.ci_llvm_root();
1324                 let link_type = t!(
1325                     std::fs::read_to_string(ci_llvm.join("link-type.txt")),
1326                     format!("CI llvm missing: {}", ci_llvm.display())
1327                 );
1328                 link_type == "dynamic"
1329             } else {
1330                 // unclear how thought-through this default is, but it maintains compatibility with
1331                 // previous behavior
1332                 false
1333             }
1334         });
1335         builder.config.llvm_link_shared.set(opt);
1336         llvm_link_shared
1337     }
1338
1339     /// Return whether we will use a downloaded, pre-compiled version of rustc, or just build from source.
1340     pub(crate) fn download_rustc(builder: &Builder<'_>) -> bool {
1341         static DOWNLOAD_RUSTC: OnceCell<bool> = OnceCell::new();
1342         if builder.config.dry_run && DOWNLOAD_RUSTC.get().is_none() {
1343             // avoid trying to actually download the commit
1344             return false;
1345         }
1346
1347         *DOWNLOAD_RUSTC.get_or_init(|| match &builder.config.download_rustc_commit {
1348             None => false,
1349             Some(commit) => {
1350                 download_ci_rustc(builder, commit);
1351                 true
1352             }
1353         })
1354     }
1355
1356     pub(crate) fn initial_rustfmt(builder: &Builder<'_>) -> Option<PathBuf> {
1357         match &mut *builder.config.initial_rustfmt.borrow_mut() {
1358             RustfmtState::SystemToolchain(p) | RustfmtState::Downloaded(p) => Some(p.clone()),
1359             RustfmtState::Unavailable => None,
1360             r @ RustfmtState::LazyEvaluated => {
1361                 if builder.config.dry_run {
1362                     return Some(PathBuf::new());
1363                 }
1364                 let path = maybe_download_rustfmt(builder);
1365                 *r = if let Some(p) = &path {
1366                     RustfmtState::Downloaded(p.clone())
1367                 } else {
1368                     RustfmtState::Unavailable
1369                 };
1370                 path
1371             }
1372         }
1373     }
1374
1375     pub fn verbose(&self) -> bool {
1376         self.verbose > 0
1377     }
1378
1379     pub fn sanitizers_enabled(&self, target: TargetSelection) -> bool {
1380         self.target_config.get(&target).map(|t| t.sanitizers).flatten().unwrap_or(self.sanitizers)
1381     }
1382
1383     pub fn any_sanitizers_enabled(&self) -> bool {
1384         self.target_config.values().any(|t| t.sanitizers == Some(true)) || self.sanitizers
1385     }
1386
1387     pub fn profiler_enabled(&self, target: TargetSelection) -> bool {
1388         self.target_config.get(&target).map(|t| t.profiler).flatten().unwrap_or(self.profiler)
1389     }
1390
1391     pub fn any_profiler_enabled(&self) -> bool {
1392         self.target_config.values().any(|t| t.profiler == Some(true)) || self.profiler
1393     }
1394
1395     pub fn llvm_enabled(&self) -> bool {
1396         self.rust_codegen_backends.contains(&INTERNER.intern_str("llvm"))
1397     }
1398
1399     pub fn llvm_libunwind(&self, target: TargetSelection) -> LlvmLibunwind {
1400         self.target_config
1401             .get(&target)
1402             .and_then(|t| t.llvm_libunwind)
1403             .or(self.llvm_libunwind_default)
1404             .unwrap_or(LlvmLibunwind::No)
1405     }
1406
1407     pub fn submodules(&self, rust_info: &GitInfo) -> bool {
1408         self.submodules.unwrap_or(rust_info.is_git())
1409     }
1410 }
1411
1412 fn set<T>(field: &mut T, val: Option<T>) {
1413     if let Some(v) = val {
1414         *field = v;
1415     }
1416 }
1417
1418 fn threads_from_config(v: u32) -> u32 {
1419     match v {
1420         0 => std::thread::available_parallelism().map_or(1, std::num::NonZeroUsize::get) as u32,
1421         n => n,
1422     }
1423 }
1424
1425 /// Returns the commit to download, or `None` if we shouldn't download CI artifacts.
1426 fn download_ci_rustc_commit(download_rustc: Option<StringOrBool>, verbose: bool) -> Option<String> {
1427     // If `download-rustc` is not set, default to rebuilding.
1428     let if_unchanged = match download_rustc {
1429         None | Some(StringOrBool::Bool(false)) => return None,
1430         Some(StringOrBool::Bool(true)) => false,
1431         Some(StringOrBool::String(s)) if s == "if-unchanged" => true,
1432         Some(StringOrBool::String(other)) => {
1433             panic!("unrecognized option for download-rustc: {}", other)
1434         }
1435     };
1436
1437     // Handle running from a directory other than the top level
1438     let top_level = output(Command::new("git").args(&["rev-parse", "--show-toplevel"]));
1439     let top_level = top_level.trim_end();
1440     let compiler = format!("{top_level}/compiler/");
1441     let library = format!("{top_level}/library/");
1442
1443     // Look for a version to compare to based on the current commit.
1444     // Only commits merged by bors will have CI artifacts.
1445     let merge_base = output(Command::new("git").args(&[
1446         "rev-list",
1447         "--author=bors@rust-lang.org",
1448         "-n1",
1449         "--first-parent",
1450         "HEAD",
1451     ]));
1452     let commit = merge_base.trim_end();
1453     if commit.is_empty() {
1454         println!("error: could not find commit hash for downloading rustc");
1455         println!("help: maybe your repository history is too shallow?");
1456         println!("help: consider disabling `download-rustc`");
1457         println!("help: or fetch enough history to include one upstream commit");
1458         exit(1);
1459     }
1460
1461     // Warn if there were changes to the compiler or standard library since the ancestor commit.
1462     let has_changes = !t!(Command::new("git")
1463         .args(&["diff-index", "--quiet", &commit, "--", &compiler, &library])
1464         .status())
1465     .success();
1466     if has_changes {
1467         if if_unchanged {
1468             if verbose {
1469                 println!(
1470                     "warning: saw changes to compiler/ or library/ since {commit}; \
1471                           ignoring `download-rustc`"
1472                 );
1473             }
1474             return None;
1475         }
1476         println!(
1477             "warning: `download-rustc` is enabled, but there are changes to \
1478                   compiler/ or library/"
1479         );
1480     }
1481
1482     Some(commit.to_string())
1483 }
1484
1485 fn maybe_download_rustfmt(builder: &Builder<'_>) -> Option<PathBuf> {
1486     #[derive(Deserialize)]
1487     struct Stage0Metadata {
1488         dist_server: String,
1489         checksums_sha256: HashMap<String, String>,
1490         rustfmt: Option<RustfmtMetadata>,
1491     }
1492     #[derive(Deserialize)]
1493     struct RustfmtMetadata {
1494         date: String,
1495         version: String,
1496     }
1497
1498     let stage0_json = builder.read(&builder.src.join("src").join("stage0.json"));
1499     let Stage0Metadata { dist_server, checksums_sha256, rustfmt } =
1500         t!(serde_json::from_str::<Stage0Metadata>(&stage0_json));
1501     let RustfmtMetadata { date, version } = rustfmt?;
1502     let channel = format!("{version}-{date}");
1503     let mut dist_server = env::var("RUSTUP_DIST_SERVER").unwrap_or(dist_server);
1504     dist_server.push_str("/dist");
1505
1506     let host = builder.config.build;
1507     let rustfmt_path = builder.config.initial_rustc.with_file_name(exe("rustfmt", host));
1508     let bin_root = builder.config.out.join(host.triple).join("stage0");
1509     let rustfmt_stamp = bin_root.join(".rustfmt-stamp");
1510     if rustfmt_path.exists() && !program_out_of_date(&rustfmt_stamp, &channel) {
1511         return Some(rustfmt_path);
1512     }
1513
1514     let filename = format!("rustfmt-{version}-{build}.tar.xz", build = host.triple);
1515     download_component(
1516         builder,
1517         &dist_server,
1518         filename,
1519         "rustfmt-preview",
1520         &date,
1521         "stage0",
1522         Some(checksums_sha256),
1523     );
1524
1525     builder.fix_bin_or_dylib(&bin_root.join("bin").join("rustfmt"));
1526     builder.fix_bin_or_dylib(&bin_root.join("bin").join("cargo-fmt"));
1527
1528     builder.create(&rustfmt_stamp, &channel);
1529     Some(rustfmt_path)
1530 }
1531
1532 fn download_ci_rustc(builder: &Builder<'_>, commit: &str) {
1533     builder.verbose(&format!("using downloaded stage2 artifacts from CI (commit {commit})"));
1534     // FIXME: support downloading artifacts from the beta channel
1535     const CHANNEL: &str = "nightly";
1536     let host = builder.config.build.triple;
1537     let bin_root = builder.out.join(host).join("ci-rustc");
1538     let rustc_stamp = bin_root.join(".rustc-stamp");
1539
1540     if !bin_root.join("bin").join("rustc").exists() || program_out_of_date(&rustc_stamp, commit) {
1541         if bin_root.exists() {
1542             t!(fs::remove_dir_all(&bin_root));
1543         }
1544         let filename = format!("rust-std-{CHANNEL}-{host}.tar.xz");
1545         let pattern = format!("rust-std-{host}");
1546         download_ci_component(builder, filename, &pattern, commit);
1547         let filename = format!("rustc-{CHANNEL}-{host}.tar.xz");
1548         download_ci_component(builder, filename, "rustc", commit);
1549         // download-rustc doesn't need its own cargo, it can just use beta's.
1550         let filename = format!("rustc-dev-{CHANNEL}-{host}.tar.xz");
1551         download_ci_component(builder, filename, "rustc-dev", commit);
1552
1553         builder.fix_bin_or_dylib(&bin_root.join("bin").join("rustc"));
1554         builder.fix_bin_or_dylib(&bin_root.join("bin").join("rustdoc"));
1555         let lib_dir = bin_root.join("lib");
1556         for lib in t!(fs::read_dir(lib_dir)) {
1557             let lib = t!(lib);
1558             if lib.path().extension() == Some(OsStr::new("so")) {
1559                 builder.fix_bin_or_dylib(&lib.path());
1560             }
1561         }
1562         t!(fs::write(rustc_stamp, commit));
1563     }
1564 }
1565
1566 /// Download a single component of a CI-built toolchain (not necessarily a published nightly).
1567 // NOTE: intentionally takes an owned string to avoid downloading multiple times by accident
1568 fn download_ci_component(builder: &Builder<'_>, filename: String, prefix: &str, commit: &str) {
1569     download_component(
1570         builder,
1571         "https://ci-artifacts.rust-lang.org/rustc-builds",
1572         filename,
1573         prefix,
1574         commit,
1575         "ci-rustc",
1576         None,
1577     )
1578 }
1579
1580 fn download_component(
1581     builder: &Builder<'_>,
1582     base_url: &str,
1583     filename: String,
1584     prefix: &str,
1585     key: &str,
1586     destination: &str,
1587     checksums: Option<HashMap<String, String>>,
1588 ) {
1589     let cache_dst = builder.out.join("cache");
1590     let cache_dir = cache_dst.join(key);
1591     if !cache_dir.exists() {
1592         t!(fs::create_dir_all(&cache_dir));
1593     }
1594
1595     let bin_root = builder.out.join(builder.config.build.triple).join(destination);
1596     let tarball = cache_dir.join(&filename);
1597     let url = format!("{key}/{filename}");
1598
1599     // For the beta compiler, put special effort into ensuring the checksums are valid.
1600     // FIXME: maybe we should do this for download-rustc as well? but it would be a pain to update
1601     // this on each and every nightly ...
1602     let checksum = if let Some(checksums) = &checksums {
1603         let error = format!(
1604             "src/stage0.json doesn't contain a checksum for {url}. \
1605             Pre-built artifacts might not be available for this \
1606             target at this time, see https://doc.rust-lang.org/nightly\
1607             /rustc/platform-support.html for more information."
1608         );
1609         // TODO: add an enum { Commit, Published } so we don't have to hardcode `dist` in two places
1610         let sha256 = checksums.get(&format!("dist/{url}")).expect(&error);
1611         if tarball.exists() {
1612             if builder.verify(&tarball, sha256) {
1613                 builder.unpack(&tarball, &bin_root, prefix);
1614                 return;
1615             } else {
1616                 builder.verbose(&format!(
1617                     "ignoring cached file {} due to failed verification",
1618                     tarball.display()
1619                 ));
1620                 builder.remove(&tarball);
1621             }
1622         }
1623         Some(sha256)
1624     } else if tarball.exists() {
1625         return;
1626     } else {
1627         None
1628     };
1629
1630     builder.download_component(base_url, &url, &tarball, "");
1631     if let Some(sha256) = checksum {
1632         if !builder.verify(&tarball, sha256) {
1633             panic!("failed to verify {}", tarball.display());
1634         }
1635     }
1636
1637     builder.unpack(&tarball, &bin_root, prefix);
1638 }