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 #[cfg(test)]
   7 mod tests;
   8
   9 use std::cell::{Cell, RefCell};
  10 use std::cmp;
  11 use std::collections::{HashMap, HashSet};
  12 use std::env;
  13 use std::fmt;
  14 use std::fs;
  15 use std::path::{Path, PathBuf};
  16 use std::process::Command;
  17 use std::str::FromStr;
  18
  19 use crate::builder::TaskPath;
  20 use crate::cache::{Interned, INTERNER};
  21 use crate::channel::{self, GitInfo};
  22 pub use crate::flags::Subcommand;
  23 use crate::flags::{Color, Flags};
  24 use crate::util::{exe, output, t};
  25 use once_cell::sync::OnceCell;
  26 use serde::{Deserialize, Deserializer};
  27
  28 macro_rules! check_ci_llvm {
  29     ($name:expr) => {
  30         assert!(
  31             $name.is_none(),
  32             "setting {} is incompatible with download-ci-llvm.",
  33             stringify!($name)
  34         );
  35     };
  36 }
  37
  38 #[derive(Clone, Default)]
  39 pub enum DryRun {
  40     /// This isn't a dry run.
  41     #[default]
  42     Disabled,
  43     /// This is a dry run enabled by bootstrap itself, so it can verify that no work is done.
  44     SelfCheck,
  45     /// This is a dry run enabled by the `--dry-run` flag.
  46     UserSelected,
  47 }
  48
  49 /// Global configuration for the entire build and/or bootstrap.
  50 ///
  51 /// This structure is derived from a combination of both `config.toml` and
  52 /// `config.mk`. As of the time of this writing it's unlikely that `config.toml`
  53 /// is used all that much, so this is primarily filled out by `config.mk` which
  54 /// is generated from `./configure`.
  55 ///
  56 /// Note that this structure is not decoded directly into, but rather it is
  57 /// filled out from the decoded forms of the structs below. For documentation
  58 /// each field, see the corresponding fields in
  59 /// `config.toml.example`.
  60 #[derive(Default)]
  61 #[cfg_attr(test, derive(Clone))]
  62 pub struct Config {
  63     pub changelog_seen: Option<usize>,
  64     pub ccache: Option<String>,
  65     /// Call Build::ninja() instead of this.
  66     pub ninja_in_file: bool,
  67     pub verbose: usize,
  68     pub submodules: Option<bool>,
  69     pub compiler_docs: bool,
  70     pub docs_minification: bool,
  71     pub docs: bool,
  72     pub locked_deps: bool,
  73     pub vendor: bool,
  74     pub target_config: HashMap<TargetSelection, Target>,
  75     pub full_bootstrap: bool,
  76     pub extended: bool,
  77     pub tools: Option<HashSet<String>>,
  78     pub sanitizers: bool,
  79     pub profiler: bool,
  80     pub ignore_git: bool,
  81     pub exclude: Vec<TaskPath>,
  82     pub include_default_paths: bool,
  83     pub rustc_error_format: Option<String>,
  84     pub json_output: bool,
  85     pub test_compare_mode: bool,
  86     pub color: Color,
  87     pub patch_binaries_for_nix: bool,
  88     pub stage0_metadata: Stage0Metadata,
  89
  90     pub on_fail: Option<String>,
  91     pub stage: u32,
  92     pub keep_stage: Vec<u32>,
  93     pub keep_stage_std: Vec<u32>,
  94     pub src: PathBuf,
  95     /// defaults to `config.toml`
  96     pub config: Option<PathBuf>,
  97     pub jobs: Option<u32>,
  98     pub cmd: Subcommand,
  99     pub incremental: bool,
 100     pub dry_run: DryRun,
 101     /// `None` if we shouldn't download CI compiler artifacts, or the commit to download if we should.
 102     #[cfg(not(test))]
 103     download_rustc_commit: Option<String>,
 104     #[cfg(test)]
 105     pub download_rustc_commit: Option<String>,
 106
 107     pub deny_warnings: bool,
 108     pub backtrace_on_ice: bool,
 109
 110     // llvm codegen options
 111     pub llvm_skip_rebuild: bool,
 112     pub llvm_assertions: bool,
 113     pub llvm_tests: bool,
 114     pub llvm_plugins: bool,
 115     pub llvm_optimize: bool,
 116     pub llvm_thin_lto: bool,
 117     pub llvm_release_debuginfo: bool,
 118     pub llvm_version_check: bool,
 119     pub llvm_static_stdcpp: bool,
 120     /// `None` if `llvm_from_ci` is true and we haven't yet downloaded llvm.
 121     #[cfg(not(test))]
 122     llvm_link_shared: Cell<Option<bool>>,
 123     #[cfg(test)]
 124     pub llvm_link_shared: Cell<Option<bool>>,
 125     pub llvm_clang_cl: Option<String>,
 126     pub llvm_targets: Option<String>,
 127     pub llvm_experimental_targets: Option<String>,
 128     pub llvm_link_jobs: Option<u32>,
 129     pub llvm_version_suffix: Option<String>,
 130     pub llvm_use_linker: Option<String>,
 131     pub llvm_allow_old_toolchain: bool,
 132     pub llvm_polly: bool,
 133     pub llvm_clang: bool,
 134     pub llvm_from_ci: bool,
 135     pub llvm_build_config: HashMap<String, String>,
 136
 137     pub use_lld: bool,
 138     pub lld_enabled: bool,
 139     pub llvm_tools_enabled: bool,
 140
 141     pub llvm_cflags: Option<String>,
 142     pub llvm_cxxflags: Option<String>,
 143     pub llvm_ldflags: Option<String>,
 144     pub llvm_use_libcxx: bool,
 145
 146     // rust codegen options
 147     pub rust_optimize: bool,
 148     pub rust_codegen_units: Option<u32>,
 149     pub rust_codegen_units_std: Option<u32>,
 150     pub rust_debug_assertions: bool,
 151     pub rust_debug_assertions_std: bool,
 152     pub rust_overflow_checks: bool,
 153     pub rust_overflow_checks_std: bool,
 154     pub rust_debug_logging: bool,
 155     pub rust_debuginfo_level_rustc: u32,
 156     pub rust_debuginfo_level_std: u32,
 157     pub rust_debuginfo_level_tools: u32,
 158     pub rust_debuginfo_level_tests: u32,
 159     pub rust_split_debuginfo: SplitDebuginfo,
 160     pub rust_rpath: bool,
 161     pub rustc_parallel: bool,
 162     pub rustc_default_linker: Option<String>,
 163     pub rust_optimize_tests: bool,
 164     pub rust_dist_src: bool,
 165     pub rust_codegen_backends: Vec<Interned<String>>,
 166     pub rust_verify_llvm_ir: bool,
 167     pub rust_thin_lto_import_instr_limit: Option<u32>,
 168     pub rust_remap_debuginfo: bool,
 169     pub rust_new_symbol_mangling: Option<bool>,
 170     pub rust_profile_use: Option<String>,
 171     pub rust_profile_generate: Option<String>,
 172     pub rust_lto: RustcLto,
 173     pub llvm_profile_use: Option<String>,
 174     pub llvm_profile_generate: bool,
 175     pub llvm_libunwind_default: Option<LlvmLibunwind>,
 176     pub llvm_bolt_profile_generate: bool,
 177     pub llvm_bolt_profile_use: Option<String>,
 178
 179     pub build: TargetSelection,
 180     pub hosts: Vec<TargetSelection>,
 181     pub targets: Vec<TargetSelection>,
 182     pub local_rebuild: bool,
 183     pub jemalloc: bool,
 184     pub control_flow_guard: bool,
 185
 186     // dist misc
 187     pub dist_sign_folder: Option<PathBuf>,
 188     pub dist_upload_addr: Option<String>,
 189     pub dist_compression_formats: Option<Vec<String>>,
 190
 191     // libstd features
 192     pub backtrace: bool, // support for RUST_BACKTRACE
 193
 194     // misc
 195     pub low_priority: bool,
 196     pub channel: String,
 197     pub description: Option<String>,
 198     pub verbose_tests: bool,
 199     pub save_toolstates: Option<PathBuf>,
 200     pub print_step_timings: bool,
 201     pub print_step_rusage: bool,
 202     pub missing_tools: bool,
 203
 204     // Fallback musl-root for all targets
 205     pub musl_root: Option<PathBuf>,
 206     pub prefix: Option<PathBuf>,
 207     pub sysconfdir: Option<PathBuf>,
 208     pub datadir: Option<PathBuf>,
 209     pub docdir: Option<PathBuf>,
 210     pub bindir: PathBuf,
 211     pub libdir: Option<PathBuf>,
 212     pub mandir: Option<PathBuf>,
 213     pub codegen_tests: bool,
 214     pub nodejs: Option<PathBuf>,
 215     pub npm: Option<PathBuf>,
 216     pub gdb: Option<PathBuf>,
 217     pub python: Option<PathBuf>,
 218     pub cargo_native_static: bool,
 219     pub configure_args: Vec<String>,
 220
 221     // These are either the stage0 downloaded binaries or the locally installed ones.
 222     pub initial_cargo: PathBuf,
 223     pub initial_rustc: PathBuf,
 224     #[cfg(not(test))]
 225     initial_rustfmt: RefCell<RustfmtState>,
 226     #[cfg(test)]
 227     pub initial_rustfmt: RefCell<RustfmtState>,
 228     pub out: PathBuf,
 229     pub rust_info: channel::GitInfo,
 230 }
 231
 232 #[derive(Default, Deserialize)]
 233 #[cfg_attr(test, derive(Clone))]
 234 pub struct Stage0Metadata {
 235     pub config: Stage0Config,
 236     pub checksums_sha256: HashMap<String, String>,
 237     pub rustfmt: Option<RustfmtMetadata>,
 238 }
 239 #[derive(Default, Deserialize)]
 240 #[cfg_attr(test, derive(Clone))]
 241 pub struct Stage0Config {
 242     pub dist_server: String,
 243     pub artifacts_server: String,
 244     pub artifacts_with_llvm_assertions_server: String,
 245     pub git_merge_commit_email: String,
 246     pub nightly_branch: String,
 247 }
 248 #[derive(Default, Deserialize)]
 249 #[cfg_attr(test, derive(Clone))]
 250 pub struct RustfmtMetadata {
 251     pub date: String,
 252     pub version: String,
 253 }
 254
 255 #[derive(Clone, Debug)]
 256 pub enum RustfmtState {
 257     SystemToolchain(PathBuf),
 258     Downloaded(PathBuf),
 259     Unavailable,
 260     LazyEvaluated,
 261 }
 262
 263 impl Default for RustfmtState {
 264     fn default() -> Self {
 265         RustfmtState::LazyEvaluated
 266     }
 267 }
 268
 269 #[derive(Debug, Clone, Copy, PartialEq)]
 270 pub enum LlvmLibunwind {
 271     No,
 272     InTree,
 273     System,
 274 }
 275
 276 impl Default for LlvmLibunwind {
 277     fn default() -> Self {
 278         Self::No
 279     }
 280 }
 281
 282 impl FromStr for LlvmLibunwind {
 283     type Err = String;
 284
 285     fn from_str(value: &str) -> Result<Self, Self::Err> {
 286         match value {
 287             "no" => Ok(Self::No),
 288             "in-tree" => Ok(Self::InTree),
 289             "system" => Ok(Self::System),
 290             invalid => Err(format!("Invalid value '{}' for rust.llvm-libunwind config.", invalid)),
 291         }
 292     }
 293 }
 294
 295 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 296 pub enum SplitDebuginfo {
 297     Packed,
 298     Unpacked,
 299     Off,
 300 }
 301
 302 impl Default for SplitDebuginfo {
 303     fn default() -> Self {
 304         SplitDebuginfo::Off
 305     }
 306 }
 307
 308 impl std::str::FromStr for SplitDebuginfo {
 309     type Err = ();
 310
 311     fn from_str(s: &str) -> Result<Self, Self::Err> {
 312         match s {
 313             "packed" => Ok(SplitDebuginfo::Packed),
 314             "unpacked" => Ok(SplitDebuginfo::Unpacked),
 315             "off" => Ok(SplitDebuginfo::Off),
 316             _ => Err(()),
 317         }
 318     }
 319 }
 320
 321 impl SplitDebuginfo {
 322     /// Returns the default `-Csplit-debuginfo` value for the current target. See the comment for
 323     /// `rust.split-debuginfo` in `config.toml.example`.
 324     fn default_for_platform(target: &str) -> Self {
 325         if target.contains("apple") {
 326             SplitDebuginfo::Unpacked
 327         } else if target.contains("windows") {
 328             SplitDebuginfo::Packed
 329         } else {
 330             SplitDebuginfo::Off
 331         }
 332     }
 333 }
 334
 335 /// LTO mode used for compiling rustc itself.
 336 #[derive(Default, Clone)]
 337 pub enum RustcLto {
 338     #[default]
 339     ThinLocal,
 340     Thin,
 341     Fat,
 342 }
 343
 344 impl std::str::FromStr for RustcLto {
 345     type Err = String;
 346
 347     fn from_str(s: &str) -> Result<Self, Self::Err> {
 348         match s {
 349             "thin-local" => Ok(RustcLto::ThinLocal),
 350             "thin" => Ok(RustcLto::Thin),
 351             "fat" => Ok(RustcLto::Fat),
 352             _ => Err(format!("Invalid value for rustc LTO: {}", s)),
 353         }
 354     }
 355 }
 356
 357 #[derive(Copy, Clone, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
 358 pub struct TargetSelection {
 359     pub triple: Interned<String>,
 360     file: Option<Interned<String>>,
 361 }
 362
 363 impl TargetSelection {
 364     pub fn from_user(selection: &str) -> Self {
 365         let path = Path::new(selection);
 366
 367         let (triple, file) = if path.exists() {
 368             let triple = path
 369                 .file_stem()
 370                 .expect("Target specification file has no file stem")
 371                 .to_str()
 372                 .expect("Target specification file stem is not UTF-8");
 373
 374             (triple, Some(selection))
 375         } else {
 376             (selection, None)
 377         };
 378
 379         let triple = INTERNER.intern_str(triple);
 380         let file = file.map(|f| INTERNER.intern_str(f));
 381
 382         Self { triple, file }
 383     }
 384
 385     pub fn rustc_target_arg(&self) -> &str {
 386         self.file.as_ref().unwrap_or(&self.triple)
 387     }
 388
 389     pub fn contains(&self, needle: &str) -> bool {
 390         self.triple.contains(needle)
 391     }
 392
 393     pub fn starts_with(&self, needle: &str) -> bool {
 394         self.triple.starts_with(needle)
 395     }
 396
 397     pub fn ends_with(&self, needle: &str) -> bool {
 398         self.triple.ends_with(needle)
 399     }
 400 }
 401
 402 impl fmt::Display for TargetSelection {
 403     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 404         write!(f, "{}", self.triple)?;
 405         if let Some(file) = self.file {
 406             write!(f, "({})", file)?;
 407         }
 408         Ok(())
 409     }
 410 }
 411
 412 impl fmt::Debug for TargetSelection {
 413     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 414         write!(f, "{}", self)
 415     }
 416 }
 417
 418 impl PartialEq<&str> for TargetSelection {
 419     fn eq(&self, other: &&str) -> bool {
 420         self.triple == *other
 421     }
 422 }
 423
 424 /// Per-target configuration stored in the global configuration structure.
 425 #[derive(Default)]
 426 #[cfg_attr(test, derive(Clone))]
 427 pub struct Target {
 428     /// Some(path to llvm-config) if using an external LLVM.
 429     pub llvm_config: Option<PathBuf>,
 430     pub llvm_has_rust_patches: Option<bool>,
 431     /// Some(path to FileCheck) if one was specified.
 432     pub llvm_filecheck: Option<PathBuf>,
 433     pub llvm_libunwind: Option<LlvmLibunwind>,
 434     pub cc: Option<PathBuf>,
 435     pub cxx: Option<PathBuf>,
 436     pub ar: Option<PathBuf>,
 437     pub ranlib: Option<PathBuf>,
 438     pub default_linker: Option<PathBuf>,
 439     pub linker: Option<PathBuf>,
 440     pub ndk: Option<PathBuf>,
 441     pub sanitizers: Option<bool>,
 442     pub profiler: Option<bool>,
 443     pub crt_static: Option<bool>,
 444     pub musl_root: Option<PathBuf>,
 445     pub musl_libdir: Option<PathBuf>,
 446     pub wasi_root: Option<PathBuf>,
 447     pub qemu_rootfs: Option<PathBuf>,
 448     pub no_std: bool,
 449 }
 450
 451 impl Target {
 452     pub fn from_triple(triple: &str) -> Self {
 453         let mut target: Self = Default::default();
 454         if triple.contains("-none")
 455             || triple.contains("nvptx")
 456             || triple.contains("switch")
 457             || triple.contains("-uefi")
 458         {
 459             target.no_std = true;
 460         }
 461         target
 462     }
 463 }
 464 /// Structure of the `config.toml` file that configuration is read from.
 465 ///
 466 /// This structure uses `Decodable` to automatically decode a TOML configuration
 467 /// file into this format, and then this is traversed and written into the above
 468 /// `Config` structure.
 469 #[derive(Deserialize, Default)]
 470 #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 471 struct TomlConfig {
 472     changelog_seen: Option<usize>,
 473     build: Option<Build>,
 474     install: Option<Install>,
 475     llvm: Option<Llvm>,
 476     rust: Option<Rust>,
 477     target: Option<HashMap<String, TomlTarget>>,
 478     dist: Option<Dist>,
 479     profile: Option<String>,
 480 }
 481
 482 trait Merge {
 483     fn merge(&mut self, other: Self);
 484 }
 485
 486 impl Merge for TomlConfig {
 487     fn merge(
 488         &mut self,
 489         TomlConfig { build, install, llvm, rust, dist, target, profile: _, changelog_seen: _ }: Self,
 490     ) {
 491         fn do_merge<T: Merge>(x: &mut Option<T>, y: Option<T>) {
 492             if let Some(new) = y {
 493                 if let Some(original) = x {
 494                     original.merge(new);
 495                 } else {
 496                     *x = Some(new);
 497                 }
 498             }
 499         }
 500         do_merge(&mut self.build, build);
 501         do_merge(&mut self.install, install);
 502         do_merge(&mut self.llvm, llvm);
 503         do_merge(&mut self.rust, rust);
 504         do_merge(&mut self.dist, dist);
 505         assert!(target.is_none(), "merging target-specific config is not currently supported");
 506     }
 507 }
 508
 509 // We are using a decl macro instead of a derive proc macro here to reduce the compile time of
 510 // rustbuild.
 511 macro_rules! define_config {
 512     ($(#[$attr:meta])* struct $name:ident {
 513         $($field:ident: Option<$field_ty:ty> = $field_key:literal,)*
 514     }) => {
 515         $(#[$attr])*
 516         struct $name {
 517             $($field: Option<$field_ty>,)*
 518         }
 519
 520         impl Merge for $name {
 521             fn merge(&mut self, other: Self) {
 522                 $(
 523                     if !self.$field.is_some() {
 524                         self.$field = other.$field;
 525                     }
 526                 )*
 527             }
 528         }
 529
 530         // The following is a trimmed version of what serde_derive generates. All parts not relevant
 531         // for toml deserialization have been removed. This reduces the binary size and improves
 532         // compile time of rustbuild.
 533         impl<'de> Deserialize<'de> for $name {
 534             fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
 535             where
 536                 D: Deserializer<'de>,
 537             {
 538                 struct Field;
 539                 impl<'de> serde::de::Visitor<'de> for Field {
 540                     type Value = $name;
 541                     fn expecting(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
 542                         f.write_str(concat!("struct ", stringify!($name)))
 543                     }
 544
 545                     #[inline]
 546                     fn visit_map<A>(self, mut map: A) -> Result<Self::Value, A::Error>
 547                     where
 548                         A: serde::de::MapAccess<'de>,
 549                     {
 550                         $(let mut $field: Option<$field_ty> = None;)*
 551                         while let Some(key) =
 552                             match serde::de::MapAccess::next_key::<String>(&mut map) {
 553                                 Ok(val) => val,
 554                                 Err(err) => {
 555                                     return Err(err);
 556                                 }
 557                             }
 558                         {
 559                             match &*key {
 560                                 $($field_key => {
 561                                     if $field.is_some() {
 562                                         return Err(<A::Error as serde::de::Error>::duplicate_field(
 563                                             $field_key,
 564                                         ));
 565                                     }
 566                                     $field = match serde::de::MapAccess::next_value::<$field_ty>(
 567                                         &mut map,
 568                                     ) {
 569                                         Ok(val) => Some(val),
 570                                         Err(err) => {
 571                                             return Err(err);
 572                                         }
 573                                     };
 574                                 })*
 575                                 key => {
 576                                     return Err(serde::de::Error::unknown_field(key, FIELDS));
 577                                 }
 578                             }
 579                         }
 580                         Ok($name { $($field),* })
 581                     }
 582                 }
 583                 const FIELDS: &'static [&'static str] = &[
 584                     $($field_key,)*
 585                 ];
 586                 Deserializer::deserialize_struct(
 587                     deserializer,
 588                     stringify!($name),
 589                     FIELDS,
 590                     Field,
 591                 )
 592             }
 593         }
 594     }
 595 }
 596
 597 define_config! {
 598     /// TOML representation of various global build decisions.
 599     #[derive(Default)]
 600     struct Build {
 601         build: Option<String> = "build",
 602         host: Option<Vec<String>> = "host",
 603         target: Option<Vec<String>> = "target",
 604         build_dir: Option<String> = "build-dir",
 605         cargo: Option<String> = "cargo",
 606         rustc: Option<String> = "rustc",
 607         rustfmt: Option<PathBuf> = "rustfmt",
 608         docs: Option<bool> = "docs",
 609         compiler_docs: Option<bool> = "compiler-docs",
 610         docs_minification: Option<bool> = "docs-minification",
 611         submodules: Option<bool> = "submodules",
 612         gdb: Option<String> = "gdb",
 613         nodejs: Option<String> = "nodejs",
 614         npm: Option<String> = "npm",
 615         python: Option<String> = "python",
 616         locked_deps: Option<bool> = "locked-deps",
 617         vendor: Option<bool> = "vendor",
 618         full_bootstrap: Option<bool> = "full-bootstrap",
 619         extended: Option<bool> = "extended",
 620         tools: Option<HashSet<String>> = "tools",
 621         verbose: Option<usize> = "verbose",
 622         sanitizers: Option<bool> = "sanitizers",
 623         profiler: Option<bool> = "profiler",
 624         cargo_native_static: Option<bool> = "cargo-native-static",
 625         low_priority: Option<bool> = "low-priority",
 626         configure_args: Option<Vec<String>> = "configure-args",
 627         local_rebuild: Option<bool> = "local-rebuild",
 628         print_step_timings: Option<bool> = "print-step-timings",
 629         print_step_rusage: Option<bool> = "print-step-rusage",
 630         check_stage: Option<u32> = "check-stage",
 631         doc_stage: Option<u32> = "doc-stage",
 632         build_stage: Option<u32> = "build-stage",
 633         test_stage: Option<u32> = "test-stage",
 634         install_stage: Option<u32> = "install-stage",
 635         dist_stage: Option<u32> = "dist-stage",
 636         bench_stage: Option<u32> = "bench-stage",
 637         patch_binaries_for_nix: Option<bool> = "patch-binaries-for-nix",
 638         metrics: Option<bool> = "metrics",
 639     }
 640 }
 641
 642 define_config! {
 643     /// TOML representation of various global install decisions.
 644     struct Install {
 645         prefix: Option<String> = "prefix",
 646         sysconfdir: Option<String> = "sysconfdir",
 647         docdir: Option<String> = "docdir",
 648         bindir: Option<String> = "bindir",
 649         libdir: Option<String> = "libdir",
 650         mandir: Option<String> = "mandir",
 651         datadir: Option<String> = "datadir",
 652     }
 653 }
 654
 655 define_config! {
 656     /// TOML representation of how the LLVM build is configured.
 657     struct Llvm {
 658         skip_rebuild: Option<bool> = "skip-rebuild",
 659         optimize: Option<bool> = "optimize",
 660         thin_lto: Option<bool> = "thin-lto",
 661         release_debuginfo: Option<bool> = "release-debuginfo",
 662         assertions: Option<bool> = "assertions",
 663         tests: Option<bool> = "tests",
 664         plugins: Option<bool> = "plugins",
 665         ccache: Option<StringOrBool> = "ccache",
 666         version_check: Option<bool> = "version-check",
 667         static_libstdcpp: Option<bool> = "static-libstdcpp",
 668         ninja: Option<bool> = "ninja",
 669         targets: Option<String> = "targets",
 670         experimental_targets: Option<String> = "experimental-targets",
 671         link_jobs: Option<u32> = "link-jobs",
 672         link_shared: Option<bool> = "link-shared",
 673         version_suffix: Option<String> = "version-suffix",
 674         clang_cl: Option<String> = "clang-cl",
 675         cflags: Option<String> = "cflags",
 676         cxxflags: Option<String> = "cxxflags",
 677         ldflags: Option<String> = "ldflags",
 678         use_libcxx: Option<bool> = "use-libcxx",
 679         use_linker: Option<String> = "use-linker",
 680         allow_old_toolchain: Option<bool> = "allow-old-toolchain",
 681         polly: Option<bool> = "polly",
 682         clang: Option<bool> = "clang",
 683         download_ci_llvm: Option<StringOrBool> = "download-ci-llvm",
 684         build_config: Option<HashMap<String, String>> = "build-config",
 685     }
 686 }
 687
 688 define_config! {
 689     struct Dist {
 690         sign_folder: Option<String> = "sign-folder",
 691         gpg_password_file: Option<String> = "gpg-password-file",
 692         upload_addr: Option<String> = "upload-addr",
 693         src_tarball: Option<bool> = "src-tarball",
 694         missing_tools: Option<bool> = "missing-tools",
 695         compression_formats: Option<Vec<String>> = "compression-formats",
 696     }
 697 }
 698
 699 #[derive(Debug, Deserialize)]
 700 #[serde(untagged)]
 701 enum StringOrBool {
 702     String(String),
 703     Bool(bool),
 704 }
 705
 706 impl Default for StringOrBool {
 707     fn default() -> StringOrBool {
 708         StringOrBool::Bool(false)
 709     }
 710 }
 711
 712 define_config! {
 713     /// TOML representation of how the Rust build is configured.
 714     struct Rust {
 715         optimize: Option<bool> = "optimize",
 716         debug: Option<bool> = "debug",
 717         codegen_units: Option<u32> = "codegen-units",
 718         codegen_units_std: Option<u32> = "codegen-units-std",
 719         debug_assertions: Option<bool> = "debug-assertions",
 720         debug_assertions_std: Option<bool> = "debug-assertions-std",
 721         overflow_checks: Option<bool> = "overflow-checks",
 722         overflow_checks_std: Option<bool> = "overflow-checks-std",
 723         debug_logging: Option<bool> = "debug-logging",
 724         debuginfo_level: Option<u32> = "debuginfo-level",
 725         debuginfo_level_rustc: Option<u32> = "debuginfo-level-rustc",
 726         debuginfo_level_std: Option<u32> = "debuginfo-level-std",
 727         debuginfo_level_tools: Option<u32> = "debuginfo-level-tools",
 728         debuginfo_level_tests: Option<u32> = "debuginfo-level-tests",
 729         split_debuginfo: Option<String> = "split-debuginfo",
 730         run_dsymutil: Option<bool> = "run-dsymutil",
 731         backtrace: Option<bool> = "backtrace",
 732         incremental: Option<bool> = "incremental",
 733         parallel_compiler: Option<bool> = "parallel-compiler",
 734         default_linker: Option<String> = "default-linker",
 735         channel: Option<String> = "channel",
 736         description: Option<String> = "description",
 737         musl_root: Option<String> = "musl-root",
 738         rpath: Option<bool> = "rpath",
 739         verbose_tests: Option<bool> = "verbose-tests",
 740         optimize_tests: Option<bool> = "optimize-tests",
 741         codegen_tests: Option<bool> = "codegen-tests",
 742         ignore_git: Option<bool> = "ignore-git",
 743         dist_src: Option<bool> = "dist-src",
 744         save_toolstates: Option<String> = "save-toolstates",
 745         codegen_backends: Option<Vec<String>> = "codegen-backends",
 746         lld: Option<bool> = "lld",
 747         use_lld: Option<bool> = "use-lld",
 748         llvm_tools: Option<bool> = "llvm-tools",
 749         deny_warnings: Option<bool> = "deny-warnings",
 750         backtrace_on_ice: Option<bool> = "backtrace-on-ice",
 751         verify_llvm_ir: Option<bool> = "verify-llvm-ir",
 752         thin_lto_import_instr_limit: Option<u32> = "thin-lto-import-instr-limit",
 753         remap_debuginfo: Option<bool> = "remap-debuginfo",
 754         jemalloc: Option<bool> = "jemalloc",
 755         test_compare_mode: Option<bool> = "test-compare-mode",
 756         llvm_libunwind: Option<String> = "llvm-libunwind",
 757         control_flow_guard: Option<bool> = "control-flow-guard",
 758         new_symbol_mangling: Option<bool> = "new-symbol-mangling",
 759         profile_generate: Option<String> = "profile-generate",
 760         profile_use: Option<String> = "profile-use",
 761         // ignored; this is set from an env var set by bootstrap.py
 762         download_rustc: Option<StringOrBool> = "download-rustc",
 763         lto: Option<String> = "lto",
 764     }
 765 }
 766
 767 define_config! {
 768     /// TOML representation of how each build target is configured.
 769     struct TomlTarget {
 770         cc: Option<String> = "cc",
 771         cxx: Option<String> = "cxx",
 772         ar: Option<String> = "ar",
 773         ranlib: Option<String> = "ranlib",
 774         default_linker: Option<PathBuf> = "default-linker",
 775         linker: Option<String> = "linker",
 776         llvm_config: Option<String> = "llvm-config",
 777         llvm_has_rust_patches: Option<bool> = "llvm-has-rust-patches",
 778         llvm_filecheck: Option<String> = "llvm-filecheck",
 779         llvm_libunwind: Option<String> = "llvm-libunwind",
 780         android_ndk: Option<String> = "android-ndk",
 781         sanitizers: Option<bool> = "sanitizers",
 782         profiler: Option<bool> = "profiler",
 783         crt_static: Option<bool> = "crt-static",
 784         musl_root: Option<String> = "musl-root",
 785         musl_libdir: Option<String> = "musl-libdir",
 786         wasi_root: Option<String> = "wasi-root",
 787         qemu_rootfs: Option<String> = "qemu-rootfs",
 788         no_std: Option<bool> = "no-std",
 789     }
 790 }
 791
 792 impl Config {
 793     pub fn default_opts() -> Config {
 794         let mut config = Config::default();
 795         config.llvm_optimize = true;
 796         config.ninja_in_file = true;
 797         config.llvm_version_check = true;
 798         config.llvm_static_stdcpp = false;
 799         config.backtrace = true;
 800         config.rust_optimize = true;
 801         config.rust_optimize_tests = true;
 802         config.submodules = None;
 803         config.docs = true;
 804         config.docs_minification = true;
 805         config.rust_rpath = true;
 806         config.channel = "dev".to_string();
 807         config.codegen_tests = true;
 808         config.rust_dist_src = true;
 809         config.rust_codegen_backends = vec![INTERNER.intern_str("llvm")];
 810         config.deny_warnings = true;
 811         config.bindir = "bin".into();
 812
 813         // set by build.rs
 814         config.build = TargetSelection::from_user(&env!("BUILD_TRIPLE"));
 815
 816         let manifest_dir = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
 817         // Undo `src/bootstrap`
 818         config.src = manifest_dir.parent().unwrap().parent().unwrap().to_owned();
 819         config.out = PathBuf::from("build");
 820
 821         config
 822     }
 823
 824     pub fn parse(args: &[String]) -> Config {
 825         #[cfg(test)]
 826         let get_toml = |_: &_| TomlConfig::default();
 827         #[cfg(not(test))]
 828         let get_toml = |file: &Path| {
 829             let contents =
 830                 t!(fs::read_to_string(file), format!("config file {} not found", file.display()));
 831             // Deserialize to Value and then TomlConfig to prevent the Deserialize impl of
 832             // TomlConfig and sub types to be monomorphized 5x by toml.
 833             match toml::from_str(&contents)
 834                 .and_then(|table: toml::Value| TomlConfig::deserialize(table))
 835             {
 836                 Ok(table) => table,
 837                 Err(err) => {
 838                     eprintln!("failed to parse TOML configuration '{}': {}", file.display(), err);
 839                     crate::detail_exit(2);
 840                 }
 841             }
 842         };
 843
 844         Self::parse_inner(args, get_toml)
 845     }
 846
 847     fn parse_inner<'a>(args: &[String], get_toml: impl 'a + Fn(&Path) -> TomlConfig) -> Config {
 848         let flags = Flags::parse(&args);
 849         let mut config = Config::default_opts();
 850
 851         // Set flags.
 852         config.exclude = flags.exclude.into_iter().map(|path| TaskPath::parse(path)).collect();
 853         config.include_default_paths = flags.include_default_paths;
 854         config.rustc_error_format = flags.rustc_error_format;
 855         config.json_output = flags.json_output;
 856         config.on_fail = flags.on_fail;
 857         config.jobs = flags.jobs.map(threads_from_config);
 858         config.cmd = flags.cmd;
 859         config.incremental = flags.incremental;
 860         config.dry_run = if flags.dry_run { DryRun::UserSelected } else { DryRun::Disabled };
 861         config.keep_stage = flags.keep_stage;
 862         config.keep_stage_std = flags.keep_stage_std;
 863         config.color = flags.color;
 864         if let Some(value) = flags.deny_warnings {
 865             config.deny_warnings = value;
 866         }
 867         config.llvm_profile_use = flags.llvm_profile_use;
 868         config.llvm_profile_generate = flags.llvm_profile_generate;
 869         config.llvm_bolt_profile_generate = flags.llvm_bolt_profile_generate;
 870         config.llvm_bolt_profile_use = flags.llvm_bolt_profile_use;
 871
 872         if config.llvm_bolt_profile_generate && config.llvm_bolt_profile_use.is_some() {
 873             eprintln!(
 874                 "Cannot use both `llvm_bolt_profile_generate` and `llvm_bolt_profile_use` at the same time"
 875             );
 876             crate::detail_exit(1);
 877         }
 878
 879         // Infer the rest of the configuration.
 880
 881         // Infer the source directory. This is non-trivial because we want to support a downloaded bootstrap binary,
 882         // running on a completely machine from where it was compiled.
 883         let mut cmd = Command::new("git");
 884         // NOTE: we cannot support running from outside the repository because the only path we have available
 885         // is set at compile time, which can be wrong if bootstrap was downloaded from source.
 886         // We still support running outside the repository if we find we aren't in a git directory.
 887         cmd.arg("rev-parse").arg("--show-toplevel");
 888         // Discard stderr because we expect this to fail when building from a tarball.
 889         let output = cmd
 890             .stderr(std::process::Stdio::null())
 891             .output()
 892             .ok()
 893             .and_then(|output| if output.status.success() { Some(output) } else { None });
 894         if let Some(output) = output {
 895             let git_root = String::from_utf8(output.stdout).unwrap();
 896             // We need to canonicalize this path to make sure it uses backslashes instead of forward slashes.
 897             let git_root = PathBuf::from(git_root.trim()).canonicalize().unwrap();
 898             let s = git_root.to_str().unwrap();
 899
 900             // Bootstrap is quite bad at handling /? in front of paths
 901             let src = match s.strip_prefix("\\\\?\\") {
 902                 Some(p) => PathBuf::from(p),
 903                 None => PathBuf::from(git_root),
 904             };
 905             // If this doesn't have at least `stage0.json`, we guessed wrong. This can happen when,
 906             // for example, the build directory is inside of another unrelated git directory.
 907             // In that case keep the original `CARGO_MANIFEST_DIR` handling.
 908             //
 909             // NOTE: this implies that downloadable bootstrap isn't supported when the build directory is outside
 910             // the source directory. We could fix that by setting a variable from all three of python, ./x, and x.ps1.
 911             if src.join("src").join("stage0.json").exists() {
 912                 config.src = src;
 913             }
 914         } else {
 915             // We're building from a tarball, not git sources.
 916             // We don't support pre-downloaded bootstrap in this case.
 917         }
 918
 919         if cfg!(test) {
 920             // Use the build directory of the original x.py invocation, so that we can set `initial_rustc` properly.
 921             config.out = Path::new(
 922                 &env::var_os("CARGO_TARGET_DIR").expect("cargo test directly is not supported"),
 923             )
 924             .parent()
 925             .unwrap()
 926             .to_path_buf();
 927         }
 928
 929         let stage0_json = t!(std::fs::read(&config.src.join("src").join("stage0.json")));
 930
 931         config.stage0_metadata = t!(serde_json::from_slice::<Stage0Metadata>(&stage0_json));
 932
 933         // Read from `--config`, then `RUST_BOOTSTRAP_CONFIG`, then `./config.toml`, then `config.toml` in the root directory.
 934         let toml_path = flags
 935             .config
 936             .clone()
 937             .or_else(|| env::var_os("RUST_BOOTSTRAP_CONFIG").map(PathBuf::from));
 938         let using_default_path = toml_path.is_none();
 939         let mut toml_path = toml_path.unwrap_or_else(|| PathBuf::from("config.toml"));
 940         if using_default_path && !toml_path.exists() {
 941             toml_path = config.src.join(toml_path);
 942         }
 943
 944         // Give a hard error if `--config` or `RUST_BOOTSTRAP_CONFIG` are set to a missing path,
 945         // but not if `config.toml` hasn't been created.
 946         let mut toml = if !using_default_path || toml_path.exists() {
 947             config.config = Some(toml_path.clone());
 948             get_toml(&toml_path)
 949         } else {
 950             config.config = None;
 951             TomlConfig::default()
 952         };
 953
 954         if let Some(include) = &toml.profile {
 955             let mut include_path = config.src.clone();
 956             include_path.push("src");
 957             include_path.push("bootstrap");
 958             include_path.push("defaults");
 959             include_path.push(format!("config.{}.toml", include));
 960             let included_toml = get_toml(&include_path);
 961             toml.merge(included_toml);
 962         }
 963
 964         config.changelog_seen = toml.changelog_seen;
 965
 966         let build = toml.build.unwrap_or_default();
 967
 968         set(&mut config.out, flags.build_dir.or_else(|| build.build_dir.map(PathBuf::from)));
 969         // NOTE: Bootstrap spawns various commands with different working directories.
 970         // To avoid writing to random places on the file system, `config.out` needs to be an absolute path.
 971         if !config.out.is_absolute() {
 972             // `canonicalize` requires the path to already exist. Use our vendored copy of `absolute` instead.
 973             config.out = crate::util::absolute(&config.out);
 974         }
 975
 976         config.initial_rustc = build
 977             .rustc
 978             .map(PathBuf::from)
 979             .unwrap_or_else(|| config.out.join(config.build.triple).join("stage0/bin/rustc"));
 980         config.initial_cargo = build
 981             .cargo
 982             .map(PathBuf::from)
 983             .unwrap_or_else(|| config.out.join(config.build.triple).join("stage0/bin/cargo"));
 984
 985         // NOTE: it's important this comes *after* we set `initial_rustc` just above.
 986         if config.dry_run() {
 987             let dir = config.out.join("tmp-dry-run");
 988             t!(fs::create_dir_all(&dir));
 989             config.out = dir;
 990         }
 991
 992         config.hosts = if let Some(arg_host) = flags.host {
 993             arg_host
 994         } else if let Some(file_host) = build.host {
 995             file_host.iter().map(|h| TargetSelection::from_user(h)).collect()
 996         } else {
 997             vec![config.build]
 998         };
 999         config.targets = if let Some(arg_target) = flags.target {
1000             arg_target
1001         } else if let Some(file_target) = build.target {
1002             file_target.iter().map(|h| TargetSelection::from_user(h)).collect()
1003         } else {
1004             // If target is *not* configured, then default to the host
1005             // toolchains.
1006             config.hosts.clone()
1007         };
1008
1009         config.nodejs = build.nodejs.map(PathBuf::from);
1010         config.npm = build.npm.map(PathBuf::from);
1011         config.gdb = build.gdb.map(PathBuf::from);
1012         config.python = build.python.map(PathBuf::from);
1013         config.submodules = build.submodules;
1014         set(&mut config.low_priority, build.low_priority);
1015         set(&mut config.compiler_docs, build.compiler_docs);
1016         set(&mut config.docs_minification, build.docs_minification);
1017         set(&mut config.docs, build.docs);
1018         set(&mut config.locked_deps, build.locked_deps);
1019         set(&mut config.vendor, build.vendor);
1020         set(&mut config.full_bootstrap, build.full_bootstrap);
1021         set(&mut config.extended, build.extended);
1022         config.tools = build.tools;
1023         set(&mut config.verbose, build.verbose);
1024         set(&mut config.sanitizers, build.sanitizers);
1025         set(&mut config.profiler, build.profiler);
1026         set(&mut config.cargo_native_static, build.cargo_native_static);
1027         set(&mut config.configure_args, build.configure_args);
1028         set(&mut config.local_rebuild, build.local_rebuild);
1029         set(&mut config.print_step_timings, build.print_step_timings);
1030         set(&mut config.print_step_rusage, build.print_step_rusage);
1031         set(&mut config.patch_binaries_for_nix, build.patch_binaries_for_nix);
1032
1033         config.verbose = cmp::max(config.verbose, flags.verbose);
1034
1035         if let Some(install) = toml.install {
1036             config.prefix = install.prefix.map(PathBuf::from);
1037             config.sysconfdir = install.sysconfdir.map(PathBuf::from);
1038             config.datadir = install.datadir.map(PathBuf::from);
1039             config.docdir = install.docdir.map(PathBuf::from);
1040             set(&mut config.bindir, install.bindir.map(PathBuf::from));
1041             config.libdir = install.libdir.map(PathBuf::from);
1042             config.mandir = install.mandir.map(PathBuf::from);
1043         }
1044
1045         // We want the llvm-skip-rebuild flag to take precedence over the
1046         // skip-rebuild config.toml option so we store it separately
1047         // so that we can infer the right value
1048         let mut llvm_skip_rebuild = flags.llvm_skip_rebuild;
1049
1050         // Store off these values as options because if they're not provided
1051         // we'll infer default values for them later
1052         let mut llvm_assertions = None;
1053         let mut llvm_tests = None;
1054         let mut llvm_plugins = None;
1055         let mut debug = None;
1056         let mut debug_assertions = None;
1057         let mut debug_assertions_std = None;
1058         let mut overflow_checks = None;
1059         let mut overflow_checks_std = None;
1060         let mut debug_logging = None;
1061         let mut debuginfo_level = None;
1062         let mut debuginfo_level_rustc = None;
1063         let mut debuginfo_level_std = None;
1064         let mut debuginfo_level_tools = None;
1065         let mut debuginfo_level_tests = None;
1066         let mut optimize = None;
1067         let mut ignore_git = None;
1068
1069         if let Some(rust) = toml.rust {
1070             debug = rust.debug;
1071             debug_assertions = rust.debug_assertions;
1072             debug_assertions_std = rust.debug_assertions_std;
1073             overflow_checks = rust.overflow_checks;
1074             overflow_checks_std = rust.overflow_checks_std;
1075             debug_logging = rust.debug_logging;
1076             debuginfo_level = rust.debuginfo_level;
1077             debuginfo_level_rustc = rust.debuginfo_level_rustc;
1078             debuginfo_level_std = rust.debuginfo_level_std;
1079             debuginfo_level_tools = rust.debuginfo_level_tools;
1080             debuginfo_level_tests = rust.debuginfo_level_tests;
1081             config.rust_split_debuginfo = rust
1082                 .split_debuginfo
1083                 .as_deref()
1084                 .map(SplitDebuginfo::from_str)
1085                 .map(|v| v.expect("invalid value for rust.split_debuginfo"))
1086                 .unwrap_or(SplitDebuginfo::default_for_platform(&config.build.triple));
1087             optimize = rust.optimize;
1088             ignore_git = rust.ignore_git;
1089             config.rust_new_symbol_mangling = rust.new_symbol_mangling;
1090             set(&mut config.rust_optimize_tests, rust.optimize_tests);
1091             set(&mut config.codegen_tests, rust.codegen_tests);
1092             set(&mut config.rust_rpath, rust.rpath);
1093             set(&mut config.jemalloc, rust.jemalloc);
1094             set(&mut config.test_compare_mode, rust.test_compare_mode);
1095             set(&mut config.backtrace, rust.backtrace);
1096             set(&mut config.channel, rust.channel);
1097             config.description = rust.description;
1098             set(&mut config.rust_dist_src, rust.dist_src);
1099             set(&mut config.verbose_tests, rust.verbose_tests);
1100             // in the case "false" is set explicitly, do not overwrite the command line args
1101             if let Some(true) = rust.incremental {
1102                 config.incremental = true;
1103             }
1104             set(&mut config.use_lld, rust.use_lld);
1105             set(&mut config.lld_enabled, rust.lld);
1106             set(&mut config.llvm_tools_enabled, rust.llvm_tools);
1107             config.rustc_parallel = rust.parallel_compiler.unwrap_or(false);
1108             config.rustc_default_linker = rust.default_linker;
1109             config.musl_root = rust.musl_root.map(PathBuf::from);
1110             config.save_toolstates = rust.save_toolstates.map(PathBuf::from);
1111             set(&mut config.deny_warnings, flags.deny_warnings.or(rust.deny_warnings));
1112             set(&mut config.backtrace_on_ice, rust.backtrace_on_ice);
1113             set(&mut config.rust_verify_llvm_ir, rust.verify_llvm_ir);
1114             config.rust_thin_lto_import_instr_limit = rust.thin_lto_import_instr_limit;
1115             set(&mut config.rust_remap_debuginfo, rust.remap_debuginfo);
1116             set(&mut config.control_flow_guard, rust.control_flow_guard);
1117             config.llvm_libunwind_default = rust
1118                 .llvm_libunwind
1119                 .map(|v| v.parse().expect("failed to parse rust.llvm-libunwind"));
1120
1121             if let Some(ref backends) = rust.codegen_backends {
1122                 config.rust_codegen_backends =
1123                     backends.iter().map(|s| INTERNER.intern_str(s)).collect();
1124             }
1125
1126             config.rust_codegen_units = rust.codegen_units.map(threads_from_config);
1127             config.rust_codegen_units_std = rust.codegen_units_std.map(threads_from_config);
1128             config.rust_profile_use = flags.rust_profile_use.or(rust.profile_use);
1129             config.rust_profile_generate = flags.rust_profile_generate.or(rust.profile_generate);
1130             config.download_rustc_commit = config.download_ci_rustc_commit(rust.download_rustc);
1131
1132             config.rust_lto = rust
1133                 .lto
1134                 .as_deref()
1135                 .map(|value| RustcLto::from_str(value).unwrap())
1136                 .unwrap_or_default();
1137         } else {
1138             config.rust_profile_use = flags.rust_profile_use;
1139             config.rust_profile_generate = flags.rust_profile_generate;
1140         }
1141
1142         if let Some(llvm) = toml.llvm {
1143             match llvm.ccache {
1144                 Some(StringOrBool::String(ref s)) => config.ccache = Some(s.to_string()),
1145                 Some(StringOrBool::Bool(true)) => {
1146                     config.ccache = Some("ccache".to_string());
1147                 }
1148                 Some(StringOrBool::Bool(false)) | None => {}
1149             }
1150             set(&mut config.ninja_in_file, llvm.ninja);
1151             llvm_assertions = llvm.assertions;
1152             llvm_tests = llvm.tests;
1153             llvm_plugins = llvm.plugins;
1154             llvm_skip_rebuild = llvm_skip_rebuild.or(llvm.skip_rebuild);
1155             set(&mut config.llvm_optimize, llvm.optimize);
1156             set(&mut config.llvm_thin_lto, llvm.thin_lto);
1157             set(&mut config.llvm_release_debuginfo, llvm.release_debuginfo);
1158             set(&mut config.llvm_version_check, llvm.version_check);
1159             set(&mut config.llvm_static_stdcpp, llvm.static_libstdcpp);
1160             if let Some(v) = llvm.link_shared {
1161                 config.llvm_link_shared.set(Some(v));
1162             }
1163             config.llvm_targets = llvm.targets.clone();
1164             config.llvm_experimental_targets = llvm.experimental_targets.clone();
1165             config.llvm_link_jobs = llvm.link_jobs;
1166             config.llvm_version_suffix = llvm.version_suffix.clone();
1167             config.llvm_clang_cl = llvm.clang_cl.clone();
1168
1169             config.llvm_cflags = llvm.cflags.clone();
1170             config.llvm_cxxflags = llvm.cxxflags.clone();
1171             config.llvm_ldflags = llvm.ldflags.clone();
1172             set(&mut config.llvm_use_libcxx, llvm.use_libcxx);
1173             config.llvm_use_linker = llvm.use_linker.clone();
1174             config.llvm_allow_old_toolchain = llvm.allow_old_toolchain.unwrap_or(false);
1175             config.llvm_polly = llvm.polly.unwrap_or(false);
1176             config.llvm_clang = llvm.clang.unwrap_or(false);
1177             config.llvm_build_config = llvm.build_config.clone().unwrap_or(Default::default());
1178
1179             let asserts = llvm_assertions.unwrap_or(false);
1180             config.llvm_from_ci = match llvm.download_ci_llvm {
1181                 Some(StringOrBool::String(s)) => {
1182                     assert!(s == "if-available", "unknown option `{}` for download-ci-llvm", s);
1183                     crate::native::is_ci_llvm_available(&config, asserts)
1184                 }
1185                 Some(StringOrBool::Bool(b)) => b,
1186                 None => {
1187                     config.channel == "dev" && crate::native::is_ci_llvm_available(&config, asserts)
1188                 }
1189             };
1190
1191             if config.llvm_from_ci {
1192                 // None of the LLVM options, except assertions, are supported
1193                 // when using downloaded LLVM. We could just ignore these but
1194                 // that's potentially confusing, so force them to not be
1195                 // explicitly set. The defaults and CI defaults don't
1196                 // necessarily match but forcing people to match (somewhat
1197                 // arbitrary) CI configuration locally seems bad/hard.
1198                 check_ci_llvm!(llvm.optimize);
1199                 check_ci_llvm!(llvm.thin_lto);
1200                 check_ci_llvm!(llvm.release_debuginfo);
1201                 // CI-built LLVM can be either dynamic or static. We won't know until we download it.
1202                 check_ci_llvm!(llvm.link_shared);
1203                 check_ci_llvm!(llvm.static_libstdcpp);
1204                 check_ci_llvm!(llvm.targets);
1205                 check_ci_llvm!(llvm.experimental_targets);
1206                 check_ci_llvm!(llvm.link_jobs);
1207                 check_ci_llvm!(llvm.clang_cl);
1208                 check_ci_llvm!(llvm.version_suffix);
1209                 check_ci_llvm!(llvm.cflags);
1210                 check_ci_llvm!(llvm.cxxflags);
1211                 check_ci_llvm!(llvm.ldflags);
1212                 check_ci_llvm!(llvm.use_libcxx);
1213                 check_ci_llvm!(llvm.use_linker);
1214                 check_ci_llvm!(llvm.allow_old_toolchain);
1215                 check_ci_llvm!(llvm.polly);
1216                 check_ci_llvm!(llvm.clang);
1217                 check_ci_llvm!(llvm.build_config);
1218                 check_ci_llvm!(llvm.plugins);
1219             }
1220
1221             // NOTE: can never be hit when downloading from CI, since we call `check_ci_llvm!(thin_lto)` above.
1222             if config.llvm_thin_lto && llvm.link_shared.is_none() {
1223                 // If we're building with ThinLTO on, by default we want to link
1224                 // to LLVM shared, to avoid re-doing ThinLTO (which happens in
1225                 // the link step) with each stage.
1226                 config.llvm_link_shared.set(Some(true));
1227             }
1228         } else {
1229             config.llvm_from_ci =
1230                 config.channel == "dev" && crate::native::is_ci_llvm_available(&config, false);
1231         }
1232
1233         if let Some(t) = toml.target {
1234             for (triple, cfg) in t {
1235                 let mut target = Target::from_triple(&triple);
1236
1237                 if let Some(ref s) = cfg.llvm_config {
1238                     target.llvm_config = Some(config.src.join(s));
1239                 }
1240                 target.llvm_has_rust_patches = cfg.llvm_has_rust_patches;
1241                 if let Some(ref s) = cfg.llvm_filecheck {
1242                     target.llvm_filecheck = Some(config.src.join(s));
1243                 }
1244                 target.llvm_libunwind = cfg
1245                     .llvm_libunwind
1246                     .as_ref()
1247                     .map(|v| v.parse().expect("failed to parse rust.llvm-libunwind"));
1248                 if let Some(ref s) = cfg.android_ndk {
1249                     target.ndk = Some(config.src.join(s));
1250                 }
1251                 if let Some(s) = cfg.no_std {
1252                     target.no_std = s;
1253                 }
1254                 target.cc = cfg.cc.map(PathBuf::from);
1255                 target.cxx = cfg.cxx.map(PathBuf::from);
1256                 target.ar = cfg.ar.map(PathBuf::from);
1257                 target.ranlib = cfg.ranlib.map(PathBuf::from);
1258                 target.linker = cfg.linker.map(PathBuf::from);
1259                 target.crt_static = cfg.crt_static;
1260                 target.musl_root = cfg.musl_root.map(PathBuf::from);
1261                 target.musl_libdir = cfg.musl_libdir.map(PathBuf::from);
1262                 target.wasi_root = cfg.wasi_root.map(PathBuf::from);
1263                 target.qemu_rootfs = cfg.qemu_rootfs.map(PathBuf::from);
1264                 target.sanitizers = cfg.sanitizers;
1265                 target.profiler = cfg.profiler;
1266
1267                 config.target_config.insert(TargetSelection::from_user(&triple), target);
1268             }
1269         }
1270
1271         if config.llvm_from_ci {
1272             let triple = &config.build.triple;
1273             let ci_llvm_bin = config.ci_llvm_root().join("bin");
1274             let mut build_target = config
1275                 .target_config
1276                 .entry(config.build)
1277                 .or_insert_with(|| Target::from_triple(&triple));
1278
1279             check_ci_llvm!(build_target.llvm_config);
1280             check_ci_llvm!(build_target.llvm_filecheck);
1281             build_target.llvm_config = Some(ci_llvm_bin.join(exe("llvm-config", config.build)));
1282             build_target.llvm_filecheck = Some(ci_llvm_bin.join(exe("FileCheck", config.build)));
1283         }
1284
1285         if let Some(t) = toml.dist {
1286             config.dist_sign_folder = t.sign_folder.map(PathBuf::from);
1287             config.dist_upload_addr = t.upload_addr;
1288             config.dist_compression_formats = t.compression_formats;
1289             set(&mut config.rust_dist_src, t.src_tarball);
1290             set(&mut config.missing_tools, t.missing_tools);
1291         }
1292
1293         if let Some(r) = build.rustfmt {
1294             *config.initial_rustfmt.borrow_mut() = if r.exists() {
1295                 RustfmtState::SystemToolchain(r)
1296             } else {
1297                 RustfmtState::Unavailable
1298             };
1299         } else {
1300             // If using a system toolchain for bootstrapping, see if that has rustfmt available.
1301             let host = config.build;
1302             let rustfmt_path = config.initial_rustc.with_file_name(exe("rustfmt", host));
1303             let bin_root = config.out.join(host.triple).join("stage0");
1304             if !rustfmt_path.starts_with(&bin_root) {
1305                 // Using a system-provided toolchain; we shouldn't download rustfmt.
1306                 *config.initial_rustfmt.borrow_mut() = RustfmtState::SystemToolchain(rustfmt_path);
1307             }
1308         }
1309
1310         // Now that we've reached the end of our configuration, infer the
1311         // default values for all options that we haven't otherwise stored yet.
1312
1313         config.llvm_skip_rebuild = llvm_skip_rebuild.unwrap_or(false);
1314         config.llvm_assertions = llvm_assertions.unwrap_or(false);
1315         config.llvm_tests = llvm_tests.unwrap_or(false);
1316         config.llvm_plugins = llvm_plugins.unwrap_or(false);
1317         config.rust_optimize = optimize.unwrap_or(true);
1318
1319         let default = debug == Some(true);
1320         config.rust_debug_assertions = debug_assertions.unwrap_or(default);
1321         config.rust_debug_assertions_std =
1322             debug_assertions_std.unwrap_or(config.rust_debug_assertions);
1323         config.rust_overflow_checks = overflow_checks.unwrap_or(default);
1324         config.rust_overflow_checks_std =
1325             overflow_checks_std.unwrap_or(config.rust_overflow_checks);
1326
1327         config.rust_debug_logging = debug_logging.unwrap_or(config.rust_debug_assertions);
1328
1329         let with_defaults = |debuginfo_level_specific: Option<u32>| {
1330             debuginfo_level_specific.or(debuginfo_level).unwrap_or(if debug == Some(true) {
1331                 1
1332             } else {
1333                 0
1334             })
1335         };
1336         config.rust_debuginfo_level_rustc = with_defaults(debuginfo_level_rustc);
1337         config.rust_debuginfo_level_std = with_defaults(debuginfo_level_std);
1338         config.rust_debuginfo_level_tools = with_defaults(debuginfo_level_tools);
1339         config.rust_debuginfo_level_tests = debuginfo_level_tests.unwrap_or(0);
1340
1341         let default = config.channel == "dev";
1342         config.ignore_git = ignore_git.unwrap_or(default);
1343         config.rust_info = GitInfo::new(config.ignore_git, &config.src);
1344
1345         let download_rustc = config.download_rustc_commit.is_some();
1346         // See https://github.com/rust-lang/compiler-team/issues/326
1347         config.stage = match config.cmd {
1348             Subcommand::Check { .. } => flags.stage.or(build.check_stage).unwrap_or(0),
1349             // `download-rustc` only has a speed-up for stage2 builds. Default to stage2 unless explicitly overridden.
1350             Subcommand::Doc { .. } => {
1351                 flags.stage.or(build.doc_stage).unwrap_or(if download_rustc { 2 } else { 0 })
1352             }
1353             Subcommand::Build { .. } => {
1354                 flags.stage.or(build.build_stage).unwrap_or(if download_rustc { 2 } else { 1 })
1355             }
1356             Subcommand::Test { .. } => {
1357                 flags.stage.or(build.test_stage).unwrap_or(if download_rustc { 2 } else { 1 })
1358             }
1359             Subcommand::Bench { .. } => flags.stage.or(build.bench_stage).unwrap_or(2),
1360             Subcommand::Dist { .. } => flags.stage.or(build.dist_stage).unwrap_or(2),
1361             Subcommand::Install { .. } => flags.stage.or(build.install_stage).unwrap_or(2),
1362             // These are all bootstrap tools, which don't depend on the compiler.
1363             // The stage we pass shouldn't matter, but use 0 just in case.
1364             Subcommand::Clean { .. }
1365             | Subcommand::Clippy { .. }
1366             | Subcommand::Fix { .. }
1367             | Subcommand::Run { .. }
1368             | Subcommand::Setup { .. }
1369             | Subcommand::Format { .. } => flags.stage.unwrap_or(0),
1370         };
1371
1372         // CI should always run stage 2 builds, unless it specifically states otherwise
1373         #[cfg(not(test))]
1374         if flags.stage.is_none() && crate::CiEnv::current() != crate::CiEnv::None {
1375             match config.cmd {
1376                 Subcommand::Test { .. }
1377                 | Subcommand::Doc { .. }
1378                 | Subcommand::Build { .. }
1379                 | Subcommand::Bench { .. }
1380                 | Subcommand::Dist { .. }
1381                 | Subcommand::Install { .. } => {
1382                     assert_eq!(
1383                         config.stage, 2,
1384                         "x.py should be run with `--stage 2` on CI, but was run with `--stage {}`",
1385                         config.stage,
1386                     );
1387                 }
1388                 Subcommand::Clean { .. }
1389                 | Subcommand::Check { .. }
1390                 | Subcommand::Clippy { .. }
1391                 | Subcommand::Fix { .. }
1392                 | Subcommand::Run { .. }
1393                 | Subcommand::Setup { .. }
1394                 | Subcommand::Format { .. } => {}
1395             }
1396         }
1397
1398         config
1399     }
1400
1401     pub(crate) fn dry_run(&self) -> bool {
1402         match self.dry_run {
1403             DryRun::Disabled => false,
1404             DryRun::SelfCheck | DryRun::UserSelected => true,
1405         }
1406     }
1407
1408     /// A git invocation which runs inside the source directory.
1409     ///
1410     /// Use this rather than `Command::new("git")` in order to support out-of-tree builds.
1411     pub(crate) fn git(&self) -> Command {
1412         let mut git = Command::new("git");
1413         git.current_dir(&self.src);
1414         git
1415     }
1416
1417     /// Bootstrap embeds a version number into the name of shared libraries it uploads in CI.
1418     /// Return the version it would have used for the given commit.
1419     pub(crate) fn artifact_version_part(&self, commit: &str) -> String {
1420         let (channel, version) = if self.rust_info.is_managed_git_subrepository() {
1421             let mut channel = self.git();
1422             channel.arg("show").arg(format!("{}:src/ci/channel", commit));
1423             let channel = output(&mut channel);
1424             let mut version = self.git();
1425             version.arg("show").arg(format!("{}:src/version", commit));
1426             let version = output(&mut version);
1427             (channel.trim().to_owned(), version.trim().to_owned())
1428         } else {
1429             let channel = fs::read_to_string(self.src.join("src/ci/channel"));
1430             let version = fs::read_to_string(self.src.join("src/version"));
1431             match (channel, version) {
1432                 (Ok(channel), Ok(version)) => {
1433                     (channel.trim().to_owned(), version.trim().to_owned())
1434                 }
1435                 (channel, version) => {
1436                     let src = self.src.display();
1437                     eprintln!("error: failed to determine artifact channel and/or version");
1438                     eprintln!(
1439                         "help: consider using a git checkout or ensure these files are readable"
1440                     );
1441                     if let Err(channel) = channel {
1442                         eprintln!("reading {}/src/ci/channel failed: {:?}", src, channel);
1443                     }
1444                     if let Err(version) = version {
1445                         eprintln!("reading {}/src/version failed: {:?}", src, version);
1446                     }
1447                     panic!();
1448                 }
1449             }
1450         };
1451
1452         match channel.as_str() {
1453             "stable" => version,
1454             "beta" => channel,
1455             "nightly" => channel,
1456             other => unreachable!("{:?} is not recognized as a valid channel", other),
1457         }
1458     }
1459
1460     /// Try to find the relative path of `bindir`, otherwise return it in full.
1461     pub fn bindir_relative(&self) -> &Path {
1462         let bindir = &self.bindir;
1463         if bindir.is_absolute() {
1464             // Try to make it relative to the prefix.
1465             if let Some(prefix) = &self.prefix {
1466                 if let Ok(stripped) = bindir.strip_prefix(prefix) {
1467                     return stripped;
1468                 }
1469             }
1470         }
1471         bindir
1472     }
1473
1474     /// Try to find the relative path of `libdir`.
1475     pub fn libdir_relative(&self) -> Option<&Path> {
1476         let libdir = self.libdir.as_ref()?;
1477         if libdir.is_relative() {
1478             Some(libdir)
1479         } else {
1480             // Try to make it relative to the prefix.
1481             libdir.strip_prefix(self.prefix.as_ref()?).ok()
1482         }
1483     }
1484
1485     /// The absolute path to the downloaded LLVM artifacts.
1486     pub(crate) fn ci_llvm_root(&self) -> PathBuf {
1487         assert!(self.llvm_from_ci);
1488         self.out.join(&*self.build.triple).join("ci-llvm")
1489     }
1490
1491     /// Determine whether llvm should be linked dynamically.
1492     ///
1493     /// If `false`, llvm should be linked statically.
1494     /// This is computed on demand since LLVM might have to first be downloaded from CI.
1495     pub(crate) fn llvm_link_shared(&self) -> bool {
1496         let mut opt = self.llvm_link_shared.get();
1497         if opt.is_none() && self.dry_run() {
1498             // just assume static for now - dynamic linking isn't supported on all platforms
1499             return false;
1500         }
1501
1502         let llvm_link_shared = *opt.get_or_insert_with(|| {
1503             if self.llvm_from_ci {
1504                 self.maybe_download_ci_llvm();
1505                 let ci_llvm = self.ci_llvm_root();
1506                 let link_type = t!(
1507                     std::fs::read_to_string(ci_llvm.join("link-type.txt")),
1508                     format!("CI llvm missing: {}", ci_llvm.display())
1509                 );
1510                 link_type == "dynamic"
1511             } else {
1512                 // unclear how thought-through this default is, but it maintains compatibility with
1513                 // previous behavior
1514                 false
1515             }
1516         });
1517         self.llvm_link_shared.set(opt);
1518         llvm_link_shared
1519     }
1520
1521     /// Return whether we will use a downloaded, pre-compiled version of rustc, or just build from source.
1522     pub(crate) fn download_rustc(&self) -> bool {
1523         static DOWNLOAD_RUSTC: OnceCell<bool> = OnceCell::new();
1524         if self.dry_run() && DOWNLOAD_RUSTC.get().is_none() {
1525             // avoid trying to actually download the commit
1526             return false;
1527         }
1528
1529         *DOWNLOAD_RUSTC.get_or_init(|| match &self.download_rustc_commit {
1530             None => false,
1531             Some(commit) => {
1532                 self.download_ci_rustc(commit);
1533                 true
1534             }
1535         })
1536     }
1537
1538     pub(crate) fn initial_rustfmt(&self) -> Option<PathBuf> {
1539         match &mut *self.initial_rustfmt.borrow_mut() {
1540             RustfmtState::SystemToolchain(p) | RustfmtState::Downloaded(p) => Some(p.clone()),
1541             RustfmtState::Unavailable => None,
1542             r @ RustfmtState::LazyEvaluated => {
1543                 if self.dry_run() {
1544                     return Some(PathBuf::new());
1545                 }
1546                 let path = self.maybe_download_rustfmt();
1547                 *r = if let Some(p) = &path {
1548                     RustfmtState::Downloaded(p.clone())
1549                 } else {
1550                     RustfmtState::Unavailable
1551                 };
1552                 path
1553             }
1554         }
1555     }
1556
1557     pub fn verbose(&self, msg: &str) {
1558         if self.verbose > 0 {
1559             println!("{}", msg);
1560         }
1561     }
1562
1563     pub fn sanitizers_enabled(&self, target: TargetSelection) -> bool {
1564         self.target_config.get(&target).map(|t| t.sanitizers).flatten().unwrap_or(self.sanitizers)
1565     }
1566
1567     pub fn any_sanitizers_enabled(&self) -> bool {
1568         self.target_config.values().any(|t| t.sanitizers == Some(true)) || self.sanitizers
1569     }
1570
1571     pub fn profiler_enabled(&self, target: TargetSelection) -> bool {
1572         self.target_config.get(&target).map(|t| t.profiler).flatten().unwrap_or(self.profiler)
1573     }
1574
1575     pub fn any_profiler_enabled(&self) -> bool {
1576         self.target_config.values().any(|t| t.profiler == Some(true)) || self.profiler
1577     }
1578
1579     pub fn llvm_enabled(&self) -> bool {
1580         self.rust_codegen_backends.contains(&INTERNER.intern_str("llvm"))
1581     }
1582
1583     pub fn llvm_libunwind(&self, target: TargetSelection) -> LlvmLibunwind {
1584         self.target_config
1585             .get(&target)
1586             .and_then(|t| t.llvm_libunwind)
1587             .or(self.llvm_libunwind_default)
1588             .unwrap_or(if target.contains("fuchsia") {
1589                 LlvmLibunwind::InTree
1590             } else {
1591                 LlvmLibunwind::No
1592             })
1593     }
1594
1595     pub fn submodules(&self, rust_info: &GitInfo) -> bool {
1596         self.submodules.unwrap_or(rust_info.is_managed_git_subrepository())
1597     }
1598
1599     /// Returns the commit to download, or `None` if we shouldn't download CI artifacts.
1600     fn download_ci_rustc_commit(&self, download_rustc: Option<StringOrBool>) -> Option<String> {
1601         // If `download-rustc` is not set, default to rebuilding.
1602         let if_unchanged = match download_rustc {
1603             None | Some(StringOrBool::Bool(false)) => return None,
1604             Some(StringOrBool::Bool(true)) => false,
1605             Some(StringOrBool::String(s)) if s == "if-unchanged" => true,
1606             Some(StringOrBool::String(other)) => {
1607                 panic!("unrecognized option for download-rustc: {}", other)
1608             }
1609         };
1610
1611         // Handle running from a directory other than the top level
1612         let top_level = output(self.git().args(&["rev-parse", "--show-toplevel"]));
1613         let top_level = top_level.trim_end();
1614         let compiler = format!("{top_level}/compiler/");
1615         let library = format!("{top_level}/library/");
1616
1617         // Look for a version to compare to based on the current commit.
1618         // Only commits merged by bors will have CI artifacts.
1619         let merge_base = output(
1620             self.git()
1621                 .arg("rev-list")
1622                 .arg(format!("--author={}", self.stage0_metadata.config.git_merge_commit_email))
1623                 .args(&["-n1", "--first-parent", "HEAD"]),
1624         );
1625         let commit = merge_base.trim_end();
1626         if commit.is_empty() {
1627             println!("error: could not find commit hash for downloading rustc");
1628             println!("help: maybe your repository history is too shallow?");
1629             println!("help: consider disabling `download-rustc`");
1630             println!("help: or fetch enough history to include one upstream commit");
1631             crate::detail_exit(1);
1632         }
1633
1634         // Warn if there were changes to the compiler or standard library since the ancestor commit.
1635         let has_changes = !t!(self
1636             .git()
1637             .args(&["diff-index", "--quiet", &commit, "--", &compiler, &library])
1638             .status())
1639         .success();
1640         if has_changes {
1641             if if_unchanged {
1642                 if self.verbose > 0 {
1643                     println!(
1644                         "warning: saw changes to compiler/ or library/ since {commit}; \
1645                             ignoring `download-rustc`"
1646                     );
1647                 }
1648                 return None;
1649             }
1650             println!(
1651                 "warning: `download-rustc` is enabled, but there are changes to \
1652                     compiler/ or library/"
1653             );
1654         }
1655
1656         Some(commit.to_string())
1657     }
1658 }
1659
1660 fn set<T>(field: &mut T, val: Option<T>) {
1661     if let Some(v) = val {
1662         *field = v;
1663     }
1664 }
1665
1666 fn threads_from_config(v: u32) -> u32 {
1667     match v {
1668         0 => std::thread::available_parallelism().map_or(1, std::num::NonZeroUsize::get) as u32,
1669         n => n,
1670     }
1671 }