src/bootstrap/config.rs

   1 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 //! Serialized configuration of a build.
  12 //!
  13 //! This module implements parsing `config.toml` configuration files to tweak
  14 //! how the build runs.
  15
  16 use std::collections::{HashMap, HashSet};
  17 use std::env;
  18 use std::fs::{self, File};
  19 use std::io::prelude::*;
  20 use std::path::{Path, PathBuf};
  21 use std::process;
  22 use std::cmp;
  23
  24 use num_cpus;
  25 use toml;
  26 use util::exe;
  27 use cache::{INTERNER, Interned};
  28 use flags::Flags;
  29 pub use flags::Subcommand;
  30
  31 /// Global configuration for the entire build and/or bootstrap.
  32 ///
  33 /// This structure is derived from a combination of both `config.toml` and
  34 /// `config.mk`. As of the time of this writing it's unlikely that `config.toml`
  35 /// is used all that much, so this is primarily filled out by `config.mk` which
  36 /// is generated from `./configure`.
  37 ///
  38 /// Note that this structure is not decoded directly into, but rather it is
  39 /// filled out from the decoded forms of the structs below. For documentation
  40 /// each field, see the corresponding fields in
  41 /// `config.toml.example`.
  42 #[derive(Default)]
  43 pub struct Config {
  44     pub ccache: Option<String>,
  45     pub ninja: bool,
  46     pub verbose: usize,
  47     pub submodules: bool,
  48     pub fast_submodules: bool,
  49     pub compiler_docs: bool,
  50     pub docs: bool,
  51     pub locked_deps: bool,
  52     pub vendor: bool,
  53     pub target_config: HashMap<Interned<String>, Target>,
  54     pub full_bootstrap: bool,
  55     pub extended: bool,
  56     pub tools: Option<HashSet<String>>,
  57     pub sanitizers: bool,
  58     pub profiler: bool,
  59     pub ignore_git: bool,
  60     pub exclude: Vec<PathBuf>,
  61     pub rustc_error_format: Option<String>,
  62
  63     pub run_host_only: bool,
  64
  65     pub on_fail: Option<String>,
  66     pub stage: Option<u32>,
  67     pub keep_stage: Option<u32>,
  68     pub src: PathBuf,
  69     pub jobs: Option<u32>,
  70     pub cmd: Subcommand,
  71     pub incremental: bool,
  72     pub dry_run: bool,
  73
  74     pub deny_warnings: bool,
  75     pub backtrace_on_ice: bool,
  76
  77     // llvm codegen options
  78     pub llvm_enabled: bool,
  79     pub llvm_assertions: bool,
  80     pub llvm_optimize: bool,
  81     pub llvm_release_debuginfo: bool,
  82     pub llvm_version_check: bool,
  83     pub llvm_static_stdcpp: bool,
  84     pub llvm_link_shared: bool,
  85     pub llvm_targets: Option<String>,
  86     pub llvm_experimental_targets: String,
  87     pub llvm_link_jobs: Option<u32>,
  88
  89     pub lld_enabled: bool,
  90
  91     // rust codegen options
  92     pub rust_optimize: bool,
  93     pub rust_codegen_units: Option<u32>,
  94     pub rust_debug_assertions: bool,
  95     pub rust_debuginfo: bool,
  96     pub rust_debuginfo_lines: bool,
  97     pub rust_debuginfo_only_std: bool,
  98     pub rust_debuginfo_tools: bool,
  99     pub rust_rpath: bool,
 100     pub rustc_parallel_queries: bool,
 101     pub rustc_default_linker: Option<String>,
 102     pub rust_optimize_tests: bool,
 103     pub rust_debuginfo_tests: bool,
 104     pub rust_dist_src: bool,
 105     pub rust_codegen_backends: Vec<Interned<String>>,
 106     pub rust_codegen_backends_dir: String,
 107
 108     pub build: Interned<String>,
 109     pub hosts: Vec<Interned<String>>,
 110     pub targets: Vec<Interned<String>>,
 111     pub local_rebuild: bool,
 112
 113     // dist misc
 114     pub dist_sign_folder: Option<PathBuf>,
 115     pub dist_upload_addr: Option<String>,
 116     pub dist_gpg_password_file: Option<PathBuf>,
 117
 118     // libstd features
 119     pub debug_jemalloc: bool,
 120     pub use_jemalloc: bool,
 121     pub backtrace: bool, // support for RUST_BACKTRACE
 122     pub wasm_syscall: bool,
 123
 124     // misc
 125     pub low_priority: bool,
 126     pub channel: String,
 127     pub quiet_tests: bool,
 128     pub test_miri: bool,
 129     pub save_toolstates: Option<PathBuf>,
 130     pub print_step_timings: bool,
 131
 132     // Fallback musl-root for all targets
 133     pub musl_root: Option<PathBuf>,
 134     pub prefix: Option<PathBuf>,
 135     pub sysconfdir: Option<PathBuf>,
 136     pub datadir: Option<PathBuf>,
 137     pub docdir: Option<PathBuf>,
 138     pub bindir: Option<PathBuf>,
 139     pub libdir: Option<PathBuf>,
 140     pub mandir: Option<PathBuf>,
 141     pub codegen_tests: bool,
 142     pub nodejs: Option<PathBuf>,
 143     pub gdb: Option<PathBuf>,
 144     pub python: Option<PathBuf>,
 145     pub openssl_static: bool,
 146     pub configure_args: Vec<String>,
 147
 148     // These are either the stage0 downloaded binaries or the locally installed ones.
 149     pub initial_cargo: PathBuf,
 150     pub initial_rustc: PathBuf,
 151     pub out: PathBuf,
 152 }
 153
 154 /// Per-target configuration stored in the global configuration structure.
 155 #[derive(Default)]
 156 pub struct Target {
 157     /// Some(path to llvm-config) if using an external LLVM.
 158     pub llvm_config: Option<PathBuf>,
 159     pub jemalloc: Option<PathBuf>,
 160     pub cc: Option<PathBuf>,
 161     pub cxx: Option<PathBuf>,
 162     pub ar: Option<PathBuf>,
 163     pub linker: Option<PathBuf>,
 164     pub ndk: Option<PathBuf>,
 165     pub crt_static: Option<bool>,
 166     pub musl_root: Option<PathBuf>,
 167     pub qemu_rootfs: Option<PathBuf>,
 168     pub no_std: bool,
 169 }
 170
 171 /// Structure of the `config.toml` file that configuration is read from.
 172 ///
 173 /// This structure uses `Decodable` to automatically decode a TOML configuration
 174 /// file into this format, and then this is traversed and written into the above
 175 /// `Config` structure.
 176 #[derive(Deserialize, Default)]
 177 #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 178 struct TomlConfig {
 179     build: Option<Build>,
 180     install: Option<Install>,
 181     llvm: Option<Llvm>,
 182     rust: Option<Rust>,
 183     target: Option<HashMap<String, TomlTarget>>,
 184     dist: Option<Dist>,
 185 }
 186
 187 /// TOML representation of various global build decisions.
 188 #[derive(Deserialize, Default, Clone)]
 189 #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 190 struct Build {
 191     build: Option<String>,
 192     #[serde(default)]
 193     host: Vec<String>,
 194     #[serde(default)]
 195     target: Vec<String>,
 196     cargo: Option<String>,
 197     rustc: Option<String>,
 198     low_priority: Option<bool>,
 199     compiler_docs: Option<bool>,
 200     docs: Option<bool>,
 201     submodules: Option<bool>,
 202     fast_submodules: Option<bool>,
 203     gdb: Option<String>,
 204     locked_deps: Option<bool>,
 205     vendor: Option<bool>,
 206     nodejs: Option<String>,
 207     python: Option<String>,
 208     full_bootstrap: Option<bool>,
 209     extended: Option<bool>,
 210     tools: Option<HashSet<String>>,
 211     verbose: Option<usize>,
 212     sanitizers: Option<bool>,
 213     profiler: Option<bool>,
 214     openssl_static: Option<bool>,
 215     configure_args: Option<Vec<String>>,
 216     local_rebuild: Option<bool>,
 217     print_step_timings: Option<bool>,
 218 }
 219
 220 /// TOML representation of various global install decisions.
 221 #[derive(Deserialize, Default, Clone)]
 222 #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 223 struct Install {
 224     prefix: Option<String>,
 225     sysconfdir: Option<String>,
 226     datadir: Option<String>,
 227     docdir: Option<String>,
 228     bindir: Option<String>,
 229     libdir: Option<String>,
 230     mandir: Option<String>,
 231
 232     // standard paths, currently unused
 233     infodir: Option<String>,
 234     localstatedir: Option<String>,
 235 }
 236
 237 /// TOML representation of how the LLVM build is configured.
 238 #[derive(Deserialize, Default)]
 239 #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 240 struct Llvm {
 241     enabled: Option<bool>,
 242     ccache: Option<StringOrBool>,
 243     ninja: Option<bool>,
 244     assertions: Option<bool>,
 245     optimize: Option<bool>,
 246     release_debuginfo: Option<bool>,
 247     version_check: Option<bool>,
 248     static_libstdcpp: Option<bool>,
 249     targets: Option<String>,
 250     experimental_targets: Option<String>,
 251     link_jobs: Option<u32>,
 252     link_shared: Option<bool>,
 253 }
 254
 255 #[derive(Deserialize, Default, Clone)]
 256 #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 257 struct Dist {
 258     sign_folder: Option<String>,
 259     gpg_password_file: Option<String>,
 260     upload_addr: Option<String>,
 261     src_tarball: Option<bool>,
 262 }
 263
 264 #[derive(Deserialize)]
 265 #[serde(untagged)]
 266 enum StringOrBool {
 267     String(String),
 268     Bool(bool),
 269 }
 270
 271 impl Default for StringOrBool {
 272     fn default() -> StringOrBool {
 273         StringOrBool::Bool(false)
 274     }
 275 }
 276
 277 /// TOML representation of how the Rust build is configured.
 278 #[derive(Deserialize, Default)]
 279 #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 280 struct Rust {
 281     optimize: Option<bool>,
 282     codegen_units: Option<u32>,
 283     debug_assertions: Option<bool>,
 284     debuginfo: Option<bool>,
 285     debuginfo_lines: Option<bool>,
 286     debuginfo_only_std: Option<bool>,
 287     debuginfo_tools: Option<bool>,
 288     experimental_parallel_queries: Option<bool>,
 289     debug_jemalloc: Option<bool>,
 290     use_jemalloc: Option<bool>,
 291     backtrace: Option<bool>,
 292     default_linker: Option<String>,
 293     channel: Option<String>,
 294     musl_root: Option<String>,
 295     rpath: Option<bool>,
 296     optimize_tests: Option<bool>,
 297     debuginfo_tests: Option<bool>,
 298     codegen_tests: Option<bool>,
 299     ignore_git: Option<bool>,
 300     debug: Option<bool>,
 301     dist_src: Option<bool>,
 302     quiet_tests: Option<bool>,
 303     test_miri: Option<bool>,
 304     save_toolstates: Option<String>,
 305     codegen_backends: Option<Vec<String>>,
 306     codegen_backends_dir: Option<String>,
 307     wasm_syscall: Option<bool>,
 308     lld: Option<bool>,
 309     deny_warnings: Option<bool>,
 310     backtrace_on_ice: Option<bool>,
 311 }
 312
 313 /// TOML representation of how each build target is configured.
 314 #[derive(Deserialize, Default)]
 315 #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 316 struct TomlTarget {
 317     llvm_config: Option<String>,
 318     jemalloc: Option<String>,
 319     cc: Option<String>,
 320     cxx: Option<String>,
 321     ar: Option<String>,
 322     linker: Option<String>,
 323     android_ndk: Option<String>,
 324     crt_static: Option<bool>,
 325     musl_root: Option<String>,
 326     qemu_rootfs: Option<String>,
 327 }
 328
 329 impl Config {
 330     fn path_from_python(var_key: &str) -> PathBuf {
 331         match env::var_os(var_key) {
 332             // Do not trust paths from Python and normalize them slightly (#49785).
 333             Some(var_val) => Path::new(&var_val).components().collect(),
 334             _ => panic!("expected '{}' to be set", var_key),
 335         }
 336     }
 337
 338     pub fn default_opts() -> Config {
 339         let mut config = Config::default();
 340         config.llvm_enabled = true;
 341         config.llvm_optimize = true;
 342         config.llvm_version_check = true;
 343         config.use_jemalloc = true;
 344         config.backtrace = true;
 345         config.rust_optimize = true;
 346         config.rust_optimize_tests = true;
 347         config.submodules = true;
 348         config.fast_submodules = true;
 349         config.docs = true;
 350         config.rust_rpath = true;
 351         config.channel = "dev".to_string();
 352         config.codegen_tests = true;
 353         config.ignore_git = false;
 354         config.rust_dist_src = true;
 355         config.test_miri = false;
 356         config.rust_codegen_backends = vec![INTERNER.intern_str("llvm")];
 357         config.rust_codegen_backends_dir = "codegen-backends".to_owned();
 358         config.deny_warnings = true;
 359
 360         // set by bootstrap.py
 361         config.build = INTERNER.intern_str(&env::var("BUILD").expect("'BUILD' to be set"));
 362         config.src = Config::path_from_python("SRC");
 363         config.out = Config::path_from_python("BUILD_DIR");
 364
 365         let stage0_root = config.out.join(&config.build).join("stage0/bin");
 366         config.initial_rustc = stage0_root.join(exe("rustc", &config.build));
 367         config.initial_cargo = stage0_root.join(exe("cargo", &config.build));
 368
 369         config
 370     }
 371
 372     pub fn parse(args: &[String]) -> Config {
 373         let flags = Flags::parse(&args);
 374         let file = flags.config.clone();
 375         let mut config = Config::default_opts();
 376         config.exclude = flags.exclude;
 377         config.rustc_error_format = flags.rustc_error_format;
 378         config.on_fail = flags.on_fail;
 379         config.stage = flags.stage;
 380         config.jobs = flags.jobs;
 381         config.cmd = flags.cmd;
 382         config.incremental = flags.incremental;
 383         config.dry_run = flags.dry_run;
 384         config.keep_stage = flags.keep_stage;
 385         if let Some(value) = flags.warnings {
 386             config.deny_warnings = value;
 387         }
 388
 389         if config.dry_run {
 390             let dir = config.out.join("tmp-dry-run");
 391             t!(fs::create_dir_all(&dir));
 392             config.out = dir;
 393         }
 394
 395         // If --target was specified but --host wasn't specified, don't run any host-only tests.
 396         config.run_host_only = !(flags.host.is_empty() && !flags.target.is_empty());
 397
 398         let toml = file.map(|file| {
 399             let mut f = t!(File::open(&file));
 400             let mut contents = String::new();
 401             t!(f.read_to_string(&mut contents));
 402             match toml::from_str(&contents) {
 403                 Ok(table) => table,
 404                 Err(err) => {
 405                     println!("failed to parse TOML configuration '{}': {}",
 406                         file.display(), err);
 407                     process::exit(2);
 408                 }
 409             }
 410         }).unwrap_or_else(|| TomlConfig::default());
 411
 412         let build = toml.build.clone().unwrap_or(Build::default());
 413         // set by bootstrap.py
 414         config.hosts.push(config.build.clone());
 415         for host in build.host.iter() {
 416             let host = INTERNER.intern_str(host);
 417             if !config.hosts.contains(&host) {
 418                 config.hosts.push(host);
 419             }
 420         }
 421         for target in config.hosts.iter().cloned()
 422             .chain(build.target.iter().map(|s| INTERNER.intern_str(s)))
 423         {
 424             if !config.targets.contains(&target) {
 425                 config.targets.push(target);
 426             }
 427         }
 428         config.hosts = if !flags.host.is_empty() {
 429             flags.host
 430         } else {
 431             config.hosts
 432         };
 433         config.targets = if !flags.target.is_empty() {
 434             flags.target
 435         } else {
 436             config.targets
 437         };
 438
 439
 440         config.nodejs = build.nodejs.map(PathBuf::from);
 441         config.gdb = build.gdb.map(PathBuf::from);
 442         config.python = build.python.map(PathBuf::from);
 443         set(&mut config.low_priority, build.low_priority);
 444         set(&mut config.compiler_docs, build.compiler_docs);
 445         set(&mut config.docs, build.docs);
 446         set(&mut config.submodules, build.submodules);
 447         set(&mut config.fast_submodules, build.fast_submodules);
 448         set(&mut config.locked_deps, build.locked_deps);
 449         set(&mut config.vendor, build.vendor);
 450         set(&mut config.full_bootstrap, build.full_bootstrap);
 451         set(&mut config.extended, build.extended);
 452         config.tools = build.tools;
 453         set(&mut config.verbose, build.verbose);
 454         set(&mut config.sanitizers, build.sanitizers);
 455         set(&mut config.profiler, build.profiler);
 456         set(&mut config.openssl_static, build.openssl_static);
 457         set(&mut config.configure_args, build.configure_args);
 458         set(&mut config.local_rebuild, build.local_rebuild);
 459         set(&mut config.print_step_timings, build.print_step_timings);
 460         config.verbose = cmp::max(config.verbose, flags.verbose);
 461
 462         if let Some(ref install) = toml.install {
 463             config.prefix = install.prefix.clone().map(PathBuf::from);
 464             config.sysconfdir = install.sysconfdir.clone().map(PathBuf::from);
 465             config.datadir = install.datadir.clone().map(PathBuf::from);
 466             config.docdir = install.docdir.clone().map(PathBuf::from);
 467             config.bindir = install.bindir.clone().map(PathBuf::from);
 468             config.libdir = install.libdir.clone().map(PathBuf::from);
 469             config.mandir = install.mandir.clone().map(PathBuf::from);
 470         }
 471
 472         // Store off these values as options because if they're not provided
 473         // we'll infer default values for them later
 474         let mut llvm_assertions = None;
 475         let mut debuginfo_lines = None;
 476         let mut debuginfo_only_std = None;
 477         let mut debuginfo_tools = None;
 478         let mut debug = None;
 479         let mut debug_jemalloc = None;
 480         let mut debuginfo = None;
 481         let mut debug_assertions = None;
 482         let mut optimize = None;
 483         let mut ignore_git = None;
 484
 485         if let Some(ref llvm) = toml.llvm {
 486             match llvm.ccache {
 487                 Some(StringOrBool::String(ref s)) => {
 488                     config.ccache = Some(s.to_string())
 489                 }
 490                 Some(StringOrBool::Bool(true)) => {
 491                     config.ccache = Some("ccache".to_string());
 492                 }
 493                 Some(StringOrBool::Bool(false)) | None => {}
 494             }
 495             set(&mut config.ninja, llvm.ninja);
 496             set(&mut config.llvm_enabled, llvm.enabled);
 497             llvm_assertions = llvm.assertions;
 498             set(&mut config.llvm_optimize, llvm.optimize);
 499             set(&mut config.llvm_release_debuginfo, llvm.release_debuginfo);
 500             set(&mut config.llvm_version_check, llvm.version_check);
 501             set(&mut config.llvm_static_stdcpp, llvm.static_libstdcpp);
 502             set(&mut config.llvm_link_shared, llvm.link_shared);
 503             config.llvm_targets = llvm.targets.clone();
 504             config.llvm_experimental_targets = llvm.experimental_targets.clone()
 505                 .unwrap_or("WebAssembly".to_string());
 506             config.llvm_link_jobs = llvm.link_jobs;
 507         }
 508
 509         if let Some(ref rust) = toml.rust {
 510             debug = rust.debug;
 511             debug_assertions = rust.debug_assertions;
 512             debuginfo = rust.debuginfo;
 513             debuginfo_lines = rust.debuginfo_lines;
 514             debuginfo_only_std = rust.debuginfo_only_std;
 515             debuginfo_tools = rust.debuginfo_tools;
 516             optimize = rust.optimize;
 517             ignore_git = rust.ignore_git;
 518             debug_jemalloc = rust.debug_jemalloc;
 519             set(&mut config.rust_optimize_tests, rust.optimize_tests);
 520             set(&mut config.rust_debuginfo_tests, rust.debuginfo_tests);
 521             set(&mut config.codegen_tests, rust.codegen_tests);
 522             set(&mut config.rust_rpath, rust.rpath);
 523             set(&mut config.use_jemalloc, rust.use_jemalloc);
 524             set(&mut config.backtrace, rust.backtrace);
 525             set(&mut config.channel, rust.channel.clone());
 526             set(&mut config.rust_dist_src, rust.dist_src);
 527             set(&mut config.quiet_tests, rust.quiet_tests);
 528             set(&mut config.test_miri, rust.test_miri);
 529             set(&mut config.wasm_syscall, rust.wasm_syscall);
 530             set(&mut config.lld_enabled, rust.lld);
 531             config.rustc_parallel_queries = rust.experimental_parallel_queries.unwrap_or(false);
 532             config.rustc_default_linker = rust.default_linker.clone();
 533             config.musl_root = rust.musl_root.clone().map(PathBuf::from);
 534             config.save_toolstates = rust.save_toolstates.clone().map(PathBuf::from);
 535             set(&mut config.deny_warnings, rust.deny_warnings.or(flags.warnings));
 536             set(&mut config.backtrace_on_ice, rust.backtrace_on_ice);
 537
 538             if let Some(ref backends) = rust.codegen_backends {
 539                 config.rust_codegen_backends = backends.iter()
 540                     .map(|s| INTERNER.intern_str(s))
 541                     .collect();
 542             }
 543
 544             set(&mut config.rust_codegen_backends_dir, rust.codegen_backends_dir.clone());
 545
 546             match rust.codegen_units {
 547                 Some(0) => config.rust_codegen_units = Some(num_cpus::get() as u32),
 548                 Some(n) => config.rust_codegen_units = Some(n),
 549                 None => {}
 550             }
 551         }
 552
 553         if let Some(ref t) = toml.target {
 554             for (triple, cfg) in t {
 555                 let mut target = Target::default();
 556
 557                 if let Some(ref s) = cfg.llvm_config {
 558                     target.llvm_config = Some(config.src.join(s));
 559                 }
 560                 if let Some(ref s) = cfg.jemalloc {
 561                     target.jemalloc = Some(config.src.join(s));
 562                 }
 563                 if let Some(ref s) = cfg.android_ndk {
 564                     target.ndk = Some(config.src.join(s));
 565                 }
 566                 target.cc = cfg.cc.clone().map(PathBuf::from);
 567                 target.cxx = cfg.cxx.clone().map(PathBuf::from);
 568                 target.ar = cfg.ar.clone().map(PathBuf::from);
 569                 target.linker = cfg.linker.clone().map(PathBuf::from);
 570                 target.crt_static = cfg.crt_static.clone();
 571                 target.musl_root = cfg.musl_root.clone().map(PathBuf::from);
 572                 target.qemu_rootfs = cfg.qemu_rootfs.clone().map(PathBuf::from);
 573
 574                 config.target_config.insert(INTERNER.intern_string(triple.clone()), target);
 575             }
 576         }
 577
 578         if let Some(ref t) = toml.dist {
 579             config.dist_sign_folder = t.sign_folder.clone().map(PathBuf::from);
 580             config.dist_gpg_password_file = t.gpg_password_file.clone().map(PathBuf::from);
 581             config.dist_upload_addr = t.upload_addr.clone();
 582             set(&mut config.rust_dist_src, t.src_tarball);
 583         }
 584
 585         // Now that we've reached the end of our configuration, infer the
 586         // default values for all options that we haven't otherwise stored yet.
 587
 588         set(&mut config.initial_rustc, build.rustc.map(PathBuf::from));
 589         set(&mut config.initial_cargo, build.cargo.map(PathBuf::from));
 590
 591         let default = false;
 592         config.llvm_assertions = llvm_assertions.unwrap_or(default);
 593
 594         let default = match &config.channel[..] {
 595             "stable" | "beta" | "nightly" => true,
 596             _ => false,
 597         };
 598         config.rust_debuginfo_lines = debuginfo_lines.unwrap_or(default);
 599         config.rust_debuginfo_only_std = debuginfo_only_std.unwrap_or(default);
 600         config.rust_debuginfo_tools = debuginfo_tools.unwrap_or(false);
 601
 602         let default = debug == Some(true);
 603         config.debug_jemalloc = debug_jemalloc.unwrap_or(default);
 604         config.rust_debuginfo = debuginfo.unwrap_or(default);
 605         config.rust_debug_assertions = debug_assertions.unwrap_or(default);
 606         config.rust_optimize = optimize.unwrap_or(!default);
 607
 608         let default = config.channel == "dev";
 609         config.ignore_git = ignore_git.unwrap_or(default);
 610
 611         config
 612     }
 613
 614     /// Try to find the relative path of `libdir`.
 615     pub fn libdir_relative(&self) -> Option<&Path> {
 616         let libdir = self.libdir.as_ref()?;
 617         if libdir.is_relative() {
 618             Some(libdir)
 619         } else {
 620             // Try to make it relative to the prefix.
 621             libdir.strip_prefix(self.prefix.as_ref()?).ok()
 622         }
 623     }
 624
 625     pub fn verbose(&self) -> bool {
 626         self.verbose > 0
 627     }
 628
 629     pub fn very_verbose(&self) -> bool {
 630         self.verbose > 1
 631     }
 632 }
 633
 634 fn set<T>(field: &mut T, val: Option<T>) {
 635     if let Some(v) = val {
 636         *field = v;
 637     }
 638 }