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