src/bootstrap/native.rs

   1 //! Compilation of native dependencies like LLVM.
   2 //!
   3 //! Native projects like LLVM unfortunately aren't suited just yet for
   4 //! compilation in build scripts that Cargo has. This is because the
   5 //! compilation takes a *very* long time but also because we don't want to
   6 //! compile LLVM 3 times as part of a normal bootstrap (we want it cached).
   7 //!
   8 //! LLVM and compiler-rt are essentially just wired up to everything else to
   9 //! ensure that they're always in place if needed.
  10
  11 use std::env;
  12 use std::env::consts::EXE_EXTENSION;
  13 use std::ffi::OsString;
  14 use std::fs::{self, File};
  15 use std::io;
  16 use std::path::{Path, PathBuf};
  17 use std::process::Command;
  18
  19 use build_helper::{output, t};
  20
  21 use crate::builder::{Builder, RunConfig, ShouldRun, Step};
  22 use crate::config::TargetSelection;
  23 use crate::util::{self, exe};
  24 use crate::GitRepo;
  25 use build_helper::up_to_date;
  26
  27 pub struct Meta {
  28     stamp: HashStamp,
  29     build_llvm_config: PathBuf,
  30     out_dir: PathBuf,
  31     root: String,
  32 }
  33
  34 // This returns whether we've already previously built LLVM.
  35 //
  36 // It's used to avoid busting caches during x.py check -- if we've already built
  37 // LLVM, it's fine for us to not try to avoid doing so.
  38 //
  39 // This will return the llvm-config if it can get it (but it will not build it
  40 // if not).
  41 pub fn prebuilt_llvm_config(
  42     builder: &Builder<'_>,
  43     target: TargetSelection,
  44 ) -> Result<PathBuf, Meta> {
  45     // If we're using a custom LLVM bail out here, but we can only use a
  46     // custom LLVM for the build triple.
  47     if let Some(config) = builder.config.target_config.get(&target) {
  48         if let Some(ref s) = config.llvm_config {
  49             check_llvm_version(builder, s);
  50             return Ok(s.to_path_buf());
  51         }
  52     }
  53
  54     let root = "src/llvm-project/llvm";
  55     let out_dir = builder.llvm_out(target);
  56
  57     let mut llvm_config_ret_dir = builder.llvm_out(builder.config.build);
  58     if !builder.config.build.contains("msvc") || builder.ninja() {
  59         llvm_config_ret_dir.push("build");
  60     }
  61     llvm_config_ret_dir.push("bin");
  62
  63     let build_llvm_config = llvm_config_ret_dir.join(exe("llvm-config", builder.config.build));
  64
  65     let stamp = out_dir.join("llvm-finished-building");
  66     let stamp = HashStamp::new(stamp, builder.in_tree_llvm_info.sha());
  67
  68     if builder.config.llvm_skip_rebuild && stamp.path.exists() {
  69         builder.info(
  70             "Warning: \
  71                 Using a potentially stale build of LLVM; \
  72                 This may not behave well.",
  73         );
  74         return Ok(build_llvm_config);
  75     }
  76
  77     if stamp.is_done() {
  78         if stamp.hash.is_none() {
  79             builder.info(
  80                 "Could not determine the LLVM submodule commit hash. \
  81                      Assuming that an LLVM rebuild is not necessary.",
  82             );
  83             builder.info(&format!(
  84                 "To force LLVM to rebuild, remove the file `{}`",
  85                 stamp.path.display()
  86             ));
  87         }
  88         return Ok(build_llvm_config);
  89     }
  90
  91     Err(Meta { stamp, build_llvm_config, out_dir, root: root.into() })
  92 }
  93
  94 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
  95 pub struct Llvm {
  96     pub target: TargetSelection,
  97 }
  98
  99 impl Step for Llvm {
 100     type Output = PathBuf; // path to llvm-config
 101
 102     const ONLY_HOSTS: bool = true;
 103
 104     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
 105         run.path("src/llvm-project").path("src/llvm-project/llvm").path("src/llvm")
 106     }
 107
 108     fn make_run(run: RunConfig<'_>) {
 109         run.builder.ensure(Llvm { target: run.target });
 110     }
 111
 112     /// Compile LLVM for `target`.
 113     fn run(self, builder: &Builder<'_>) -> PathBuf {
 114         let target = self.target;
 115         let target_native = if self.target.starts_with("riscv") {
 116             // RISC-V target triples in Rust is not named the same as C compiler target triples.
 117             // This converts Rust RISC-V target triples to C compiler triples.
 118             let idx = target.triple.find('-').unwrap();
 119
 120             format!("riscv{}{}", &target.triple[5..7], &target.triple[idx..])
 121         } else {
 122             target.to_string()
 123         };
 124
 125         let Meta { stamp, build_llvm_config, out_dir, root } =
 126             match prebuilt_llvm_config(builder, target) {
 127                 Ok(p) => return p,
 128                 Err(m) => m,
 129             };
 130
 131         if builder.config.llvm_link_shared
 132             && (target.contains("windows") || target.contains("apple-darwin"))
 133         {
 134             panic!("shared linking to LLVM is not currently supported on {}", target.triple);
 135         }
 136
 137         builder.info(&format!("Building LLVM for {}", target));
 138         t!(stamp.remove());
 139         let _time = util::timeit(&builder);
 140         t!(fs::create_dir_all(&out_dir));
 141
 142         // http://llvm.org/docs/CMake.html
 143         let mut cfg = cmake::Config::new(builder.src.join(root));
 144
 145         let profile = match (builder.config.llvm_optimize, builder.config.llvm_release_debuginfo) {
 146             (false, _) => "Debug",
 147             (true, false) => "Release",
 148             (true, true) => "RelWithDebInfo",
 149         };
 150
 151         // NOTE: remember to also update `config.toml.example` when changing the
 152         // defaults!
 153         let llvm_targets = match &builder.config.llvm_targets {
 154             Some(s) => s,
 155             None => {
 156                 "AArch64;ARM;Hexagon;MSP430;Mips;NVPTX;PowerPC;RISCV;\
 157                      Sparc;SystemZ;WebAssembly;X86"
 158             }
 159         };
 160
 161         let llvm_exp_targets = match builder.config.llvm_experimental_targets {
 162             Some(ref s) => s,
 163             None => "AVR",
 164         };
 165
 166         let assertions = if builder.config.llvm_assertions { "ON" } else { "OFF" };
 167
 168         cfg.out_dir(&out_dir)
 169             .profile(profile)
 170             .define("LLVM_ENABLE_ASSERTIONS", assertions)
 171             .define("LLVM_TARGETS_TO_BUILD", llvm_targets)
 172             .define("LLVM_EXPERIMENTAL_TARGETS_TO_BUILD", llvm_exp_targets)
 173             .define("LLVM_INCLUDE_EXAMPLES", "OFF")
 174             .define("LLVM_INCLUDE_DOCS", "OFF")
 175             .define("LLVM_INCLUDE_BENCHMARKS", "OFF")
 176             .define("LLVM_ENABLE_TERMINFO", "OFF")
 177             .define("LLVM_ENABLE_LIBEDIT", "OFF")
 178             .define("LLVM_ENABLE_BINDINGS", "OFF")
 179             .define("LLVM_ENABLE_Z3_SOLVER", "OFF")
 180             .define("LLVM_PARALLEL_COMPILE_JOBS", builder.jobs().to_string())
 181             .define("LLVM_TARGET_ARCH", target_native.split('-').next().unwrap())
 182             .define("LLVM_DEFAULT_TARGET_TRIPLE", target_native);
 183
 184         if target != "aarch64-apple-darwin" {
 185             cfg.define("LLVM_ENABLE_ZLIB", "ON");
 186         } else {
 187             cfg.define("LLVM_ENABLE_ZLIB", "OFF");
 188         }
 189
 190         // Are we compiling for iOS/tvOS?
 191         if target.contains("apple-ios") || target.contains("apple-tvos") {
 192             // These two defines prevent CMake from automatically trying to add a MacOSX sysroot, which leads to a compiler error.
 193             cfg.define("CMAKE_OSX_SYSROOT", "/");
 194             cfg.define("CMAKE_OSX_DEPLOYMENT_TARGET", "");
 195             // Prevent cmake from adding -bundle to CFLAGS automatically, which leads to a compiler error because "-bitcode_bundle" also gets added.
 196             cfg.define("LLVM_ENABLE_PLUGINS", "OFF");
 197             // Zlib fails to link properly, leading to a compiler error.
 198             cfg.define("LLVM_ENABLE_ZLIB", "OFF");
 199         }
 200
 201         if builder.config.llvm_thin_lto {
 202             cfg.define("LLVM_ENABLE_LTO", "Thin");
 203             if !target.contains("apple") {
 204                 cfg.define("LLVM_ENABLE_LLD", "ON");
 205             }
 206         }
 207
 208         // This setting makes the LLVM tools link to the dynamic LLVM library,
 209         // which saves both memory during parallel links and overall disk space
 210         // for the tools. We don't do this on every platform as it doesn't work
 211         // equally well everywhere.
 212         //
 213         // If we're not linking rustc to a dynamic LLVM, though, then don't link
 214         // tools to it.
 215         if builder.llvm_link_tools_dynamically(target) && builder.config.llvm_link_shared {
 216             cfg.define("LLVM_LINK_LLVM_DYLIB", "ON");
 217         }
 218
 219         // For distribution we want the LLVM tools to be *statically* linked to libstdc++
 220         if builder.config.llvm_tools_enabled {
 221             if !target.contains("msvc") {
 222                 if target.contains("apple") {
 223                     cfg.define("CMAKE_EXE_LINKER_FLAGS", "-static-libstdc++");
 224                 } else {
 225                     cfg.define("CMAKE_EXE_LINKER_FLAGS", "-Wl,-Bsymbolic -static-libstdc++");
 226                 }
 227             }
 228         }
 229
 230         if target.starts_with("riscv") {
 231             // In RISC-V, using C++ atomics require linking to `libatomic` but the LLVM build
 232             // system check cannot detect this. Therefore it is set manually here.
 233             if !builder.config.llvm_tools_enabled {
 234                 cfg.define("CMAKE_EXE_LINKER_FLAGS", "-latomic");
 235             } else {
 236                 cfg.define("CMAKE_EXE_LINKER_FLAGS", "-latomic -static-libstdc++");
 237             }
 238             cfg.define("CMAKE_SHARED_LINKER_FLAGS", "-latomic");
 239         }
 240
 241         if target.contains("msvc") {
 242             cfg.define("LLVM_USE_CRT_DEBUG", "MT");
 243             cfg.define("LLVM_USE_CRT_RELEASE", "MT");
 244             cfg.define("LLVM_USE_CRT_RELWITHDEBINFO", "MT");
 245             cfg.static_crt(true);
 246         }
 247
 248         if target.starts_with("i686") {
 249             cfg.define("LLVM_BUILD_32_BITS", "ON");
 250         }
 251
 252         let mut enabled_llvm_projects = Vec::new();
 253
 254         if util::forcing_clang_based_tests() {
 255             enabled_llvm_projects.push("clang");
 256             enabled_llvm_projects.push("compiler-rt");
 257         }
 258
 259         if let Some(true) = builder.config.llvm_polly {
 260             enabled_llvm_projects.push("polly");
 261         }
 262
 263         // We want libxml to be disabled.
 264         // See https://github.com/rust-lang/rust/pull/50104
 265         cfg.define("LLVM_ENABLE_LIBXML2", "OFF");
 266
 267         if !enabled_llvm_projects.is_empty() {
 268             enabled_llvm_projects.sort();
 269             enabled_llvm_projects.dedup();
 270             cfg.define("LLVM_ENABLE_PROJECTS", enabled_llvm_projects.join(";"));
 271         }
 272
 273         if let Some(num_linkers) = builder.config.llvm_link_jobs {
 274             if num_linkers > 0 {
 275                 cfg.define("LLVM_PARALLEL_LINK_JOBS", num_linkers.to_string());
 276             }
 277         }
 278
 279         // http://llvm.org/docs/HowToCrossCompileLLVM.html
 280         if target != builder.config.build {
 281             builder.ensure(Llvm { target: builder.config.build });
 282             // FIXME: if the llvm root for the build triple is overridden then we
 283             //        should use llvm-tblgen from there, also should verify that it
 284             //        actually exists most of the time in normal installs of LLVM.
 285             let host_bin = builder.llvm_out(builder.config.build).join("bin");
 286             cfg.define("CMAKE_CROSSCOMPILING", "True");
 287             cfg.define("LLVM_TABLEGEN", host_bin.join("llvm-tblgen").with_extension(EXE_EXTENSION));
 288             cfg.define("LLVM_NM", host_bin.join("llvm-nm").with_extension(EXE_EXTENSION));
 289             cfg.define(
 290                 "LLVM_CONFIG_PATH",
 291                 host_bin.join("llvm-config").with_extension(EXE_EXTENSION),
 292             );
 293         }
 294
 295         if let Some(ref suffix) = builder.config.llvm_version_suffix {
 296             // Allow version-suffix="" to not define a version suffix at all.
 297             if !suffix.is_empty() {
 298                 cfg.define("LLVM_VERSION_SUFFIX", suffix);
 299             }
 300         } else if builder.config.channel == "dev" {
 301             // Changes to a version suffix require a complete rebuild of the LLVM.
 302             // To avoid rebuilds during a time of version bump, don't include rustc
 303             // release number on the dev channel.
 304             cfg.define("LLVM_VERSION_SUFFIX", "-rust-dev");
 305         } else {
 306             let suffix = format!("-rust-{}-{}", builder.version, builder.config.channel);
 307             cfg.define("LLVM_VERSION_SUFFIX", suffix);
 308         }
 309
 310         if let Some(ref linker) = builder.config.llvm_use_linker {
 311             cfg.define("LLVM_USE_LINKER", linker);
 312         }
 313
 314         if let Some(true) = builder.config.llvm_allow_old_toolchain {
 315             cfg.define("LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN", "YES");
 316         }
 317
 318         configure_cmake(builder, target, &mut cfg, true);
 319
 320         // FIXME: we don't actually need to build all LLVM tools and all LLVM
 321         //        libraries here, e.g., we just want a few components and a few
 322         //        tools. Figure out how to filter them down and only build the right
 323         //        tools and libs on all platforms.
 324
 325         if builder.config.dry_run {
 326             return build_llvm_config;
 327         }
 328
 329         cfg.build();
 330
 331         t!(stamp.write());
 332
 333         build_llvm_config
 334     }
 335 }
 336
 337 fn check_llvm_version(builder: &Builder<'_>, llvm_config: &Path) {
 338     if !builder.config.llvm_version_check {
 339         return;
 340     }
 341
 342     if builder.config.dry_run {
 343         return;
 344     }
 345
 346     let mut cmd = Command::new(llvm_config);
 347     let version = output(cmd.arg("--version"));
 348     let mut parts = version.split('.').take(2).filter_map(|s| s.parse::<u32>().ok());
 349     if let (Some(major), Some(_minor)) = (parts.next(), parts.next()) {
 350         if major >= 9 {
 351             return;
 352         }
 353     }
 354     panic!("\n\nbad LLVM version: {}, need >=9.0\n\n", version)
 355 }
 356
 357 fn configure_cmake(
 358     builder: &Builder<'_>,
 359     target: TargetSelection,
 360     cfg: &mut cmake::Config,
 361     use_compiler_launcher: bool,
 362 ) {
 363     // Do not print installation messages for up-to-date files.
 364     // LLVM and LLD builds can produce a lot of those and hit CI limits on log size.
 365     cfg.define("CMAKE_INSTALL_MESSAGE", "LAZY");
 366
 367     // Do not allow the user's value of DESTDIR to influence where
 368     // LLVM will install itself. LLVM must always be installed in our
 369     // own build directories.
 370     cfg.env("DESTDIR", "");
 371
 372     if builder.ninja() {
 373         cfg.generator("Ninja");
 374     }
 375     cfg.target(&target.triple).host(&builder.config.build.triple);
 376
 377     if target != builder.config.build {
 378         if target.contains("netbsd") {
 379             cfg.define("CMAKE_SYSTEM_NAME", "NetBSD");
 380         } else if target.contains("freebsd") {
 381             cfg.define("CMAKE_SYSTEM_NAME", "FreeBSD");
 382         } else if target.contains("windows") {
 383             cfg.define("CMAKE_SYSTEM_NAME", "Windows");
 384         } else if target.contains("haiku") {
 385             cfg.define("CMAKE_SYSTEM_NAME", "Haiku");
 386         }
 387         // When cross-compiling we should also set CMAKE_SYSTEM_VERSION, but in
 388         // that case like CMake we cannot easily determine system version either.
 389         //
 390         // Since, the LLVM itself makes rather limited use of version checks in
 391         // CMakeFiles (and then only in tests), and so far no issues have been
 392         // reported, the system version is currently left unset.
 393     }
 394
 395     let sanitize_cc = |cc: &Path| {
 396         if target.contains("msvc") {
 397             OsString::from(cc.to_str().unwrap().replace("\\", "/"))
 398         } else {
 399             cc.as_os_str().to_owned()
 400         }
 401     };
 402
 403     // MSVC with CMake uses msbuild by default which doesn't respect these
 404     // vars that we'd otherwise configure. In that case we just skip this
 405     // entirely.
 406     if target.contains("msvc") && !builder.ninja() {
 407         return;
 408     }
 409
 410     let (cc, cxx) = match builder.config.llvm_clang_cl {
 411         Some(ref cl) => (cl.as_ref(), cl.as_ref()),
 412         None => (builder.cc(target), builder.cxx(target).unwrap()),
 413     };
 414
 415     // Handle msvc + ninja + ccache specially (this is what the bots use)
 416     if target.contains("msvc") && builder.ninja() && builder.config.ccache.is_some() {
 417         let mut wrap_cc = env::current_exe().expect("failed to get cwd");
 418         wrap_cc.set_file_name("sccache-plus-cl.exe");
 419
 420         cfg.define("CMAKE_C_COMPILER", sanitize_cc(&wrap_cc))
 421             .define("CMAKE_CXX_COMPILER", sanitize_cc(&wrap_cc));
 422         cfg.env("SCCACHE_PATH", builder.config.ccache.as_ref().unwrap())
 423             .env("SCCACHE_TARGET", target.triple)
 424             .env("SCCACHE_CC", &cc)
 425             .env("SCCACHE_CXX", &cxx);
 426
 427         // Building LLVM on MSVC can be a little ludicrous at times. We're so far
 428         // off the beaten path here that I'm not really sure this is even half
 429         // supported any more. Here we're trying to:
 430         //
 431         // * Build LLVM on MSVC
 432         // * Build LLVM with `clang-cl` instead of `cl.exe`
 433         // * Build a project with `sccache`
 434         // * Build for 32-bit as well
 435         // * Build with Ninja
 436         //
 437         // For `cl.exe` there are different binaries to compile 32/64 bit which
 438         // we use but for `clang-cl` there's only one which internally
 439         // multiplexes via flags. As a result it appears that CMake's detection
 440         // of a compiler's architecture and such on MSVC **doesn't** pass any
 441         // custom flags we pass in CMAKE_CXX_FLAGS below. This means that if we
 442         // use `clang-cl.exe` it's always diagnosed as a 64-bit compiler which
 443         // definitely causes problems since all the env vars are pointing to
 444         // 32-bit libraries.
 445         //
 446         // To hack around this... again... we pass an argument that's
 447         // unconditionally passed in the sccache shim. This'll get CMake to
 448         // correctly diagnose it's doing a 32-bit compilation and LLVM will
 449         // internally configure itself appropriately.
 450         if builder.config.llvm_clang_cl.is_some() && target.contains("i686") {
 451             cfg.env("SCCACHE_EXTRA_ARGS", "-m32");
 452         }
 453     } else {
 454         // If ccache is configured we inform the build a little differently how
 455         // to invoke ccache while also invoking our compilers.
 456         if use_compiler_launcher {
 457             if let Some(ref ccache) = builder.config.ccache {
 458                 cfg.define("CMAKE_C_COMPILER_LAUNCHER", ccache)
 459                     .define("CMAKE_CXX_COMPILER_LAUNCHER", ccache);
 460             }
 461         }
 462         cfg.define("CMAKE_C_COMPILER", sanitize_cc(cc))
 463             .define("CMAKE_CXX_COMPILER", sanitize_cc(cxx))
 464             .define("CMAKE_ASM_COMPILER", sanitize_cc(cc));
 465     }
 466
 467     cfg.build_arg("-j").build_arg(builder.jobs().to_string());
 468     let mut cflags = builder.cflags(target, GitRepo::Llvm).join(" ");
 469     if let Some(ref s) = builder.config.llvm_cflags {
 470         cflags.push_str(&format!(" {}", s));
 471     }
 472     // Some compiler features used by LLVM (such as thread locals) will not work on a min version below iOS 10.
 473     if target.contains("apple-ios") {
 474         if target.contains("86-") {
 475             cflags.push_str(" -miphonesimulator-version-min=10.0");
 476         } else {
 477             cflags.push_str(" -miphoneos-version-min=10.0");
 478         }
 479     }
 480     if builder.config.llvm_clang_cl.is_some() {
 481         cflags.push_str(&format!(" --target={}", target))
 482     }
 483     cfg.define("CMAKE_C_FLAGS", cflags);
 484     let mut cxxflags = builder.cflags(target, GitRepo::Llvm).join(" ");
 485     if builder.config.llvm_static_stdcpp && !target.contains("msvc") && !target.contains("netbsd") {
 486         cxxflags.push_str(" -static-libstdc++");
 487     }
 488     if let Some(ref s) = builder.config.llvm_cxxflags {
 489         cxxflags.push_str(&format!(" {}", s));
 490     }
 491     if builder.config.llvm_clang_cl.is_some() {
 492         cxxflags.push_str(&format!(" --target={}", target))
 493     }
 494     cfg.define("CMAKE_CXX_FLAGS", cxxflags);
 495     if let Some(ar) = builder.ar(target) {
 496         if ar.is_absolute() {
 497             // LLVM build breaks if `CMAKE_AR` is a relative path, for some reason it
 498             // tries to resolve this path in the LLVM build directory.
 499             cfg.define("CMAKE_AR", sanitize_cc(ar));
 500         }
 501     }
 502
 503     if let Some(ranlib) = builder.ranlib(target) {
 504         if ranlib.is_absolute() {
 505             // LLVM build breaks if `CMAKE_RANLIB` is a relative path, for some reason it
 506             // tries to resolve this path in the LLVM build directory.
 507             cfg.define("CMAKE_RANLIB", sanitize_cc(ranlib));
 508         }
 509     }
 510
 511     if let Some(ref s) = builder.config.llvm_ldflags {
 512         cfg.define("CMAKE_SHARED_LINKER_FLAGS", s);
 513         cfg.define("CMAKE_MODULE_LINKER_FLAGS", s);
 514         cfg.define("CMAKE_EXE_LINKER_FLAGS", s);
 515     }
 516
 517     if env::var_os("SCCACHE_ERROR_LOG").is_some() {
 518         cfg.env("RUSTC_LOG", "sccache=warn");
 519     }
 520 }
 521
 522 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
 523 pub struct Lld {
 524     pub target: TargetSelection,
 525 }
 526
 527 impl Step for Lld {
 528     type Output = PathBuf;
 529     const ONLY_HOSTS: bool = true;
 530
 531     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
 532         run.path("src/llvm-project/lld").path("src/tools/lld")
 533     }
 534
 535     fn make_run(run: RunConfig<'_>) {
 536         run.builder.ensure(Lld { target: run.target });
 537     }
 538
 539     /// Compile LLD for `target`.
 540     fn run(self, builder: &Builder<'_>) -> PathBuf {
 541         if builder.config.dry_run {
 542             return PathBuf::from("lld-out-dir-test-gen");
 543         }
 544         let target = self.target;
 545
 546         let llvm_config = builder.ensure(Llvm { target: self.target });
 547
 548         let out_dir = builder.lld_out(target);
 549         let done_stamp = out_dir.join("lld-finished-building");
 550         if done_stamp.exists() {
 551             return out_dir;
 552         }
 553
 554         builder.info(&format!("Building LLD for {}", target));
 555         let _time = util::timeit(&builder);
 556         t!(fs::create_dir_all(&out_dir));
 557
 558         let mut cfg = cmake::Config::new(builder.src.join("src/llvm-project/lld"));
 559         configure_cmake(builder, target, &mut cfg, true);
 560
 561         // This is an awful, awful hack. Discovered when we migrated to using
 562         // clang-cl to compile LLVM/LLD it turns out that LLD, when built out of
 563         // tree, will execute `llvm-config --cmakedir` and then tell CMake about
 564         // that directory for later processing. Unfortunately if this path has
 565         // forward slashes in it (which it basically always does on Windows)
 566         // then CMake will hit a syntax error later on as... something isn't
 567         // escaped it seems?
 568         //
 569         // Instead of attempting to fix this problem in upstream CMake and/or
 570         // LLVM/LLD we just hack around it here. This thin wrapper will take the
 571         // output from llvm-config and replace all instances of `\` with `/` to
 572         // ensure we don't hit the same bugs with escaping. It means that you
 573         // can't build on a system where your paths require `\` on Windows, but
 574         // there's probably a lot of reasons you can't do that other than this.
 575         let llvm_config_shim = env::current_exe().unwrap().with_file_name("llvm-config-wrapper");
 576
 577         cfg.out_dir(&out_dir)
 578             .profile("Release")
 579             .env("LLVM_CONFIG_REAL", &llvm_config)
 580             .define("LLVM_CONFIG_PATH", llvm_config_shim)
 581             .define("LLVM_INCLUDE_TESTS", "OFF");
 582
 583         // While we're using this horrible workaround to shim the execution of
 584         // llvm-config, let's just pile on more. I can't seem to figure out how
 585         // to build LLD as a standalone project and also cross-compile it at the
 586         // same time. It wants a natively executable `llvm-config` to learn
 587         // about LLVM, but then it learns about all the host configuration of
 588         // LLVM and tries to link to host LLVM libraries.
 589         //
 590         // To work around that we tell our shim to replace anything with the
 591         // build target with the actual target instead. This'll break parts of
 592         // LLD though which try to execute host tools, such as llvm-tblgen, so
 593         // we specifically tell it where to find those. This is likely super
 594         // brittle and will break over time. If anyone knows better how to
 595         // cross-compile LLD it would be much appreciated to fix this!
 596         if target != builder.config.build {
 597             cfg.env("LLVM_CONFIG_SHIM_REPLACE", &builder.config.build.triple)
 598                 .env("LLVM_CONFIG_SHIM_REPLACE_WITH", &target.triple)
 599                 .define(
 600                     "LLVM_TABLEGEN_EXE",
 601                     llvm_config.with_file_name("llvm-tblgen").with_extension(EXE_EXTENSION),
 602                 );
 603         }
 604
 605         // Explicitly set C++ standard, because upstream doesn't do so
 606         // for standalone builds.
 607         cfg.define("CMAKE_CXX_STANDARD", "14");
 608
 609         cfg.build();
 610
 611         t!(File::create(&done_stamp));
 612         out_dir
 613     }
 614 }
 615
 616 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
 617 pub struct TestHelpers {
 618     pub target: TargetSelection,
 619 }
 620
 621 impl Step for TestHelpers {
 622     type Output = ();
 623
 624     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
 625         run.path("src/test/auxiliary/rust_test_helpers.c")
 626     }
 627
 628     fn make_run(run: RunConfig<'_>) {
 629         run.builder.ensure(TestHelpers { target: run.target })
 630     }
 631
 632     /// Compiles the `rust_test_helpers.c` library which we used in various
 633     /// `run-pass` tests for ABI testing.
 634     fn run(self, builder: &Builder<'_>) {
 635         if builder.config.dry_run {
 636             return;
 637         }
 638         // The x86_64-fortanix-unknown-sgx target doesn't have a working C
 639         // toolchain. However, some x86_64 ELF objects can be linked
 640         // without issues. Use this hack to compile the test helpers.
 641         let target = if self.target == "x86_64-fortanix-unknown-sgx" {
 642             TargetSelection::from_user("x86_64-unknown-linux-gnu")
 643         } else {
 644             self.target
 645         };
 646         let dst = builder.test_helpers_out(target);
 647         let src = builder.src.join("src/test/auxiliary/rust_test_helpers.c");
 648         if up_to_date(&src, &dst.join("librust_test_helpers.a")) {
 649             return;
 650         }
 651
 652         builder.info("Building test helpers");
 653         t!(fs::create_dir_all(&dst));
 654         let mut cfg = cc::Build::new();
 655         // FIXME: Workaround for https://github.com/emscripten-core/emscripten/issues/9013
 656         if target.contains("emscripten") {
 657             cfg.pic(false);
 658         }
 659
 660         // We may have found various cross-compilers a little differently due to our
 661         // extra configuration, so inform cc of these compilers. Note, though, that
 662         // on MSVC we still need cc's detection of env vars (ugh).
 663         if !target.contains("msvc") {
 664             if let Some(ar) = builder.ar(target) {
 665                 cfg.archiver(ar);
 666             }
 667             cfg.compiler(builder.cc(target));
 668         }
 669         cfg.cargo_metadata(false)
 670             .out_dir(&dst)
 671             .target(&target.triple)
 672             .host(&builder.config.build.triple)
 673             .opt_level(0)
 674             .warnings(false)
 675             .debug(false)
 676             .file(builder.src.join("src/test/auxiliary/rust_test_helpers.c"))
 677             .compile("rust_test_helpers");
 678     }
 679 }
 680
 681 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
 682 pub struct Sanitizers {
 683     pub target: TargetSelection,
 684 }
 685
 686 impl Step for Sanitizers {
 687     type Output = Vec<SanitizerRuntime>;
 688
 689     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
 690         run.path("src/llvm-project/compiler-rt").path("src/sanitizers")
 691     }
 692
 693     fn make_run(run: RunConfig<'_>) {
 694         run.builder.ensure(Sanitizers { target: run.target });
 695     }
 696
 697     /// Builds sanitizer runtime libraries.
 698     fn run(self, builder: &Builder<'_>) -> Self::Output {
 699         let compiler_rt_dir = builder.src.join("src/llvm-project/compiler-rt");
 700         if !compiler_rt_dir.exists() {
 701             return Vec::new();
 702         }
 703
 704         let out_dir = builder.native_dir(self.target).join("sanitizers");
 705         let runtimes = supported_sanitizers(&out_dir, self.target, &builder.config.channel);
 706         if runtimes.is_empty() {
 707             return runtimes;
 708         }
 709
 710         let llvm_config = builder.ensure(Llvm { target: builder.config.build });
 711         if builder.config.dry_run {
 712             return runtimes;
 713         }
 714
 715         let stamp = out_dir.join("sanitizers-finished-building");
 716         let stamp = HashStamp::new(stamp, builder.in_tree_llvm_info.sha());
 717
 718         if stamp.is_done() {
 719             if stamp.hash.is_none() {
 720                 builder.info(&format!(
 721                     "Rebuild sanitizers by removing the file `{}`",
 722                     stamp.path.display()
 723                 ));
 724             }
 725             return runtimes;
 726         }
 727
 728         builder.info(&format!("Building sanitizers for {}", self.target));
 729         t!(stamp.remove());
 730         let _time = util::timeit(&builder);
 731
 732         let mut cfg = cmake::Config::new(&compiler_rt_dir);
 733         cfg.profile("Release");
 734         cfg.define("CMAKE_C_COMPILER_TARGET", self.target.triple);
 735         cfg.define("COMPILER_RT_BUILD_BUILTINS", "OFF");
 736         cfg.define("COMPILER_RT_BUILD_CRT", "OFF");
 737         cfg.define("COMPILER_RT_BUILD_LIBFUZZER", "OFF");
 738         cfg.define("COMPILER_RT_BUILD_PROFILE", "OFF");
 739         cfg.define("COMPILER_RT_BUILD_SANITIZERS", "ON");
 740         cfg.define("COMPILER_RT_BUILD_XRAY", "OFF");
 741         cfg.define("COMPILER_RT_DEFAULT_TARGET_ONLY", "ON");
 742         cfg.define("COMPILER_RT_USE_LIBCXX", "OFF");
 743         cfg.define("LLVM_CONFIG_PATH", &llvm_config);
 744
 745         // On Darwin targets the sanitizer runtimes are build as universal binaries.
 746         // Unfortunately sccache currently lacks support to build them successfully.
 747         // Disable compiler launcher on Darwin targets to avoid potential issues.
 748         let use_compiler_launcher = !self.target.contains("apple-darwin");
 749         configure_cmake(builder, self.target, &mut cfg, use_compiler_launcher);
 750
 751         t!(fs::create_dir_all(&out_dir));
 752         cfg.out_dir(out_dir);
 753
 754         for runtime in &runtimes {
 755             cfg.build_target(&runtime.cmake_target);
 756             cfg.build();
 757         }
 758         t!(stamp.write());
 759
 760         runtimes
 761     }
 762 }
 763
 764 #[derive(Clone, Debug)]
 765 pub struct SanitizerRuntime {
 766     /// CMake target used to build the runtime.
 767     pub cmake_target: String,
 768     /// Path to the built runtime library.
 769     pub path: PathBuf,
 770     /// Library filename that will be used rustc.
 771     pub name: String,
 772 }
 773
 774 /// Returns sanitizers available on a given target.
 775 fn supported_sanitizers(
 776     out_dir: &Path,
 777     target: TargetSelection,
 778     channel: &str,
 779 ) -> Vec<SanitizerRuntime> {
 780     let darwin_libs = |os: &str, components: &[&str]| -> Vec<SanitizerRuntime> {
 781         components
 782             .iter()
 783             .map(move |c| SanitizerRuntime {
 784                 cmake_target: format!("clang_rt.{}_{}_dynamic", c, os),
 785                 path: out_dir
 786                     .join(&format!("build/lib/darwin/libclang_rt.{}_{}_dynamic.dylib", c, os)),
 787                 name: format!("librustc-{}_rt.{}.dylib", channel, c),
 788             })
 789             .collect()
 790     };
 791
 792     let common_libs = |os: &str, arch: &str, components: &[&str]| -> Vec<SanitizerRuntime> {
 793         components
 794             .iter()
 795             .map(move |c| SanitizerRuntime {
 796                 cmake_target: format!("clang_rt.{}-{}", c, arch),
 797                 path: out_dir.join(&format!("build/lib/{}/libclang_rt.{}-{}.a", os, c, arch)),
 798                 name: format!("librustc-{}_rt.{}.a", channel, c),
 799             })
 800             .collect()
 801     };
 802
 803     match &*target.triple {
 804         "aarch64-apple-darwin" => darwin_libs("osx", &["asan", "lsan", "tsan"]),
 805         "aarch64-fuchsia" => common_libs("fuchsia", "aarch64", &["asan"]),
 806         "aarch64-unknown-linux-gnu" => {
 807             common_libs("linux", "aarch64", &["asan", "lsan", "msan", "tsan"])
 808         }
 809         "x86_64-apple-darwin" => darwin_libs("osx", &["asan", "lsan", "tsan"]),
 810         "x86_64-fuchsia" => common_libs("fuchsia", "x86_64", &["asan"]),
 811         "x86_64-unknown-freebsd" => common_libs("freebsd", "x86_64", &["asan", "msan", "tsan"]),
 812         "x86_64-unknown-linux-gnu" => {
 813             common_libs("linux", "x86_64", &["asan", "lsan", "msan", "tsan"])
 814         }
 815         _ => Vec::new(),
 816     }
 817 }
 818
 819 struct HashStamp {
 820     path: PathBuf,
 821     hash: Option<Vec<u8>>,
 822 }
 823
 824 impl HashStamp {
 825     fn new(path: PathBuf, hash: Option<&str>) -> Self {
 826         HashStamp { path, hash: hash.map(|s| s.as_bytes().to_owned()) }
 827     }
 828
 829     fn is_done(&self) -> bool {
 830         match fs::read(&self.path) {
 831             Ok(h) => self.hash.as_deref().unwrap_or(b"") == h.as_slice(),
 832             Err(e) if e.kind() == io::ErrorKind::NotFound => false,
 833             Err(e) => {
 834                 panic!("failed to read stamp file `{}`: {}", self.path.display(), e);
 835             }
 836         }
 837     }
 838
 839     fn remove(&self) -> io::Result<()> {
 840         match fs::remove_file(&self.path) {
 841             Ok(()) => Ok(()),
 842             Err(e) => {
 843                 if e.kind() == io::ErrorKind::NotFound {
 844                     Ok(())
 845                 } else {
 846                     Err(e)
 847                 }
 848             }
 849         }
 850     }
 851
 852     fn write(&self) -> io::Result<()> {
 853         fs::write(&self.path, self.hash.as_deref().unwrap_or(b""))
 854     }
 855 }