1 //! Compilation of native dependencies like LLVM.
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).
8 //! LLVM and compiler-rt are essentially just wired up to everything else to
9 //! ensure that they're always in place if needed.
12 use std::ffi::OsString;
13 use std::fs::{self, File};
14 use std::path::{Path, PathBuf};
15 use std::process::Command;
17 use build_helper::{output, t};
22 use crate::util::{self, exe};
23 use build_helper::up_to_date;
24 use crate::builder::{Builder, RunConfig, ShouldRun, Step};
25 use crate::cache::Interned;
28 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
30 pub target: Interned<String>,
35 type Output = PathBuf; // path to llvm-config
37 const ONLY_HOSTS: bool = true;
39 fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
40 run.path("src/llvm-project")
41 .path("src/llvm-project/llvm")
43 .path("src/llvm-emscripten")
46 fn make_run(run: RunConfig<'_>) {
47 let emscripten = run.path.ends_with("llvm-emscripten");
48 run.builder.ensure(Llvm {
54 /// Compile LLVM for `target`.
55 fn run(self, builder: &Builder<'_>) -> PathBuf {
56 let target = self.target;
57 let emscripten = self.emscripten;
59 // If we're using a custom LLVM bail out here, but we can only use a
60 // custom LLVM for the build triple.
62 if let Some(config) = builder.config.target_config.get(&target) {
63 if let Some(ref s) = config.llvm_config {
64 check_llvm_version(builder, s);
65 return s.to_path_buf()
70 let (llvm_info, root, out_dir, llvm_config_ret_dir) = if emscripten {
71 let info = &builder.emscripten_llvm_info;
72 let dir = builder.emscripten_llvm_out(target);
73 let config_dir = dir.join("bin");
74 (info, "src/llvm-emscripten", dir, config_dir)
76 let info = &builder.in_tree_llvm_info;
77 let mut dir = builder.llvm_out(builder.config.build);
78 if !builder.config.build.contains("msvc") || builder.config.ninja {
81 (info, "src/llvm-project/llvm", builder.llvm_out(target), dir.join("bin"))
84 if !llvm_info.is_git() {
86 "git could not determine the LLVM submodule commit hash. \
87 Assuming that an LLVM build is necessary.",
91 let build_llvm_config = llvm_config_ret_dir
92 .join(exe("llvm-config", &*builder.config.build));
93 let done_stamp = out_dir.join("llvm-finished-building");
95 if let Some(llvm_commit) = llvm_info.sha() {
96 if done_stamp.exists() {
97 let done_contents = t!(fs::read(&done_stamp));
99 // If LLVM was already built previously and the submodule's commit didn't change
100 // from the previous build, then no action is required.
101 if done_contents == llvm_commit.as_bytes() {
102 return build_llvm_config
107 let descriptor = if emscripten { "Emscripten " } else { "" };
108 builder.info(&format!("Building {}LLVM for {}", descriptor, target));
109 let _time = util::timeit(&builder);
110 t!(fs::create_dir_all(&out_dir));
112 // http://llvm.org/docs/CMake.html
113 let mut cfg = cmake::Config::new(builder.src.join(root));
115 let profile = match (builder.config.llvm_optimize, builder.config.llvm_release_debuginfo) {
116 (false, _) => "Debug",
117 (true, false) => "Release",
118 (true, true) => "RelWithDebInfo",
121 // NOTE: remember to also update `config.toml.example` when changing the
123 let llvm_targets = if self.emscripten {
126 match builder.config.llvm_targets {
128 None => "AArch64;ARM;Hexagon;MSP430;Mips;NVPTX;PowerPC;RISCV;\
129 Sparc;SystemZ;WebAssembly;X86",
133 let llvm_exp_targets = if self.emscripten {
136 match builder.config.llvm_experimental_targets {
142 let assertions = if builder.config.llvm_assertions {"ON"} else {"OFF"};
144 cfg.out_dir(&out_dir)
146 .define("LLVM_ENABLE_ASSERTIONS", assertions)
147 .define("LLVM_TARGETS_TO_BUILD", llvm_targets)
148 .define("LLVM_EXPERIMENTAL_TARGETS_TO_BUILD", llvm_exp_targets)
149 .define("LLVM_INCLUDE_EXAMPLES", "OFF")
150 .define("LLVM_INCLUDE_TESTS", "OFF")
151 .define("LLVM_INCLUDE_DOCS", "OFF")
152 .define("LLVM_INCLUDE_BENCHMARKS", "OFF")
153 .define("LLVM_ENABLE_ZLIB", "OFF")
154 .define("WITH_POLLY", "OFF")
155 .define("LLVM_ENABLE_TERMINFO", "OFF")
156 .define("LLVM_ENABLE_LIBEDIT", "OFF")
157 .define("LLVM_ENABLE_Z3_SOLVER", "OFF")
158 .define("LLVM_PARALLEL_COMPILE_JOBS", builder.jobs().to_string())
159 .define("LLVM_TARGET_ARCH", target.split('-').next().unwrap())
160 .define("LLVM_DEFAULT_TARGET_TRIPLE", target);
162 if builder.config.llvm_thin_lto && !emscripten {
163 cfg.define("LLVM_ENABLE_LTO", "Thin");
164 if !target.contains("apple") {
165 cfg.define("LLVM_ENABLE_LLD", "ON");
169 // By default, LLVM will automatically find OCaml and, if it finds it,
170 // install the LLVM bindings in LLVM_OCAML_INSTALL_PATH, which defaults
171 // to /usr/bin/ocaml.
172 // This causes problem for non-root builds of Rust. Side-step the issue
173 // by setting LLVM_OCAML_INSTALL_PATH to a relative path, so it installs
175 cfg.define("LLVM_OCAML_INSTALL_PATH",
176 env::var_os("LLVM_OCAML_INSTALL_PATH").unwrap_or_else(|| "usr/lib/ocaml".into()));
178 let want_lldb = builder.config.lldb_enabled && !self.emscripten;
180 // This setting makes the LLVM tools link to the dynamic LLVM library,
181 // which saves both memory during parallel links and overall disk space
182 // for the tools. We don't do this on every platform as it doesn't work
183 // equally well everywhere.
184 if builder.llvm_link_tools_dynamically(target) && !emscripten {
185 cfg.define("LLVM_LINK_LLVM_DYLIB", "ON");
188 // For distribution we want the LLVM tools to be *statically* linked to libstdc++
189 if builder.config.llvm_tools_enabled || want_lldb {
190 if !target.contains("windows") {
191 if target.contains("apple") {
192 cfg.define("CMAKE_EXE_LINKER_FLAGS", "-static-libstdc++");
194 cfg.define("CMAKE_EXE_LINKER_FLAGS", "-Wl,-Bsymbolic -static-libstdc++");
199 if target.contains("msvc") {
200 cfg.define("LLVM_USE_CRT_DEBUG", "MT");
201 cfg.define("LLVM_USE_CRT_RELEASE", "MT");
202 cfg.define("LLVM_USE_CRT_RELWITHDEBINFO", "MT");
203 cfg.static_crt(true);
206 if target.starts_with("i686") {
207 cfg.define("LLVM_BUILD_32_BITS", "ON");
210 let mut enabled_llvm_projects = Vec::new();
212 if util::forcing_clang_based_tests() {
213 enabled_llvm_projects.push("clang");
214 enabled_llvm_projects.push("compiler-rt");
218 enabled_llvm_projects.push("clang");
219 enabled_llvm_projects.push("lldb");
220 // For the time being, disable code signing.
221 cfg.define("LLDB_CODESIGN_IDENTITY", "");
222 cfg.define("LLDB_NO_DEBUGSERVER", "ON");
224 // LLDB requires libxml2; but otherwise we want it to be disabled.
225 // See https://github.com/rust-lang/rust/pull/50104
226 cfg.define("LLVM_ENABLE_LIBXML2", "OFF");
229 if enabled_llvm_projects.len() > 0 {
230 enabled_llvm_projects.sort();
231 enabled_llvm_projects.dedup();
232 cfg.define("LLVM_ENABLE_PROJECTS", enabled_llvm_projects.join(";"));
235 if let Some(num_linkers) = builder.config.llvm_link_jobs {
237 cfg.define("LLVM_PARALLEL_LINK_JOBS", num_linkers.to_string());
241 // http://llvm.org/docs/HowToCrossCompileLLVM.html
242 if target != builder.config.build && !emscripten {
243 builder.ensure(Llvm {
244 target: builder.config.build,
247 // FIXME: if the llvm root for the build triple is overridden then we
248 // should use llvm-tblgen from there, also should verify that it
249 // actually exists most of the time in normal installs of LLVM.
250 let host = builder.llvm_out(builder.config.build).join("bin/llvm-tblgen");
251 cfg.define("CMAKE_CROSSCOMPILING", "True")
252 .define("LLVM_TABLEGEN", &host);
254 if target.contains("netbsd") {
255 cfg.define("CMAKE_SYSTEM_NAME", "NetBSD");
256 } else if target.contains("freebsd") {
257 cfg.define("CMAKE_SYSTEM_NAME", "FreeBSD");
260 cfg.define("LLVM_NATIVE_BUILD", builder.llvm_out(builder.config.build).join("build"));
263 if let Some(ref suffix) = builder.config.llvm_version_suffix {
264 // Allow version-suffix="" to not define a version suffix at all.
265 if !suffix.is_empty() {
266 cfg.define("LLVM_VERSION_SUFFIX", suffix);
269 let mut default_suffix = format!(
271 channel::CFG_RELEASE_NUM,
272 builder.config.channel,
274 if let Some(sha) = llvm_info.sha_short() {
275 default_suffix.push_str("-");
276 default_suffix.push_str(sha);
278 cfg.define("LLVM_VERSION_SUFFIX", default_suffix);
281 if let Some(ref linker) = builder.config.llvm_use_linker {
282 cfg.define("LLVM_USE_LINKER", linker);
285 if let Some(true) = builder.config.llvm_allow_old_toolchain {
286 cfg.define("LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN", "YES");
289 if let Some(ref python) = builder.config.python {
290 cfg.define("PYTHON_EXECUTABLE", python);
293 configure_cmake(builder, target, &mut cfg);
295 // FIXME: we don't actually need to build all LLVM tools and all LLVM
296 // libraries here, e.g., we just want a few components and a few
297 // tools. Figure out how to filter them down and only build the right
298 // tools and libs on all platforms.
300 if builder.config.dry_run {
301 return build_llvm_config;
306 if let Some(llvm_commit) = llvm_info.sha() {
307 t!(fs::write(&done_stamp, llvm_commit));
314 fn check_llvm_version(builder: &Builder<'_>, llvm_config: &Path) {
315 if !builder.config.llvm_version_check {
319 if builder.config.dry_run {
323 let mut cmd = Command::new(llvm_config);
324 let version = output(cmd.arg("--version"));
325 let mut parts = version.split('.').take(2)
326 .filter_map(|s| s.parse::<u32>().ok());
327 if let (Some(major), Some(_minor)) = (parts.next(), parts.next()) {
332 panic!("\n\nbad LLVM version: {}, need >=6.0\n\n", version)
335 fn configure_cmake(builder: &Builder<'_>,
336 target: Interned<String>,
337 cfg: &mut cmake::Config) {
338 // Do not print installation messages for up-to-date files.
339 // LLVM and LLD builds can produce a lot of those and hit CI limits on log size.
340 cfg.define("CMAKE_INSTALL_MESSAGE", "LAZY");
342 if builder.config.ninja {
343 cfg.generator("Ninja");
346 .host(&builder.config.build);
348 let sanitize_cc = |cc: &Path| {
349 if target.contains("msvc") {
350 OsString::from(cc.to_str().unwrap().replace("\\", "/"))
352 cc.as_os_str().to_owned()
356 // MSVC with CMake uses msbuild by default which doesn't respect these
357 // vars that we'd otherwise configure. In that case we just skip this
359 if target.contains("msvc") && !builder.config.ninja {
363 let (cc, cxx) = match builder.config.llvm_clang_cl {
364 Some(ref cl) => (cl.as_ref(), cl.as_ref()),
365 None => (builder.cc(target), builder.cxx(target).unwrap()),
368 // Handle msvc + ninja + ccache specially (this is what the bots use)
369 if target.contains("msvc") &&
370 builder.config.ninja &&
371 builder.config.ccache.is_some()
373 let mut wrap_cc = env::current_exe().expect("failed to get cwd");
374 wrap_cc.set_file_name("sccache-plus-cl.exe");
376 cfg.define("CMAKE_C_COMPILER", sanitize_cc(&wrap_cc))
377 .define("CMAKE_CXX_COMPILER", sanitize_cc(&wrap_cc));
378 cfg.env("SCCACHE_PATH",
379 builder.config.ccache.as_ref().unwrap())
380 .env("SCCACHE_TARGET", target)
381 .env("SCCACHE_CC", &cc)
382 .env("SCCACHE_CXX", &cxx);
384 // Building LLVM on MSVC can be a little ludicrous at times. We're so far
385 // off the beaten path here that I'm not really sure this is even half
386 // supported any more. Here we're trying to:
388 // * Build LLVM on MSVC
389 // * Build LLVM with `clang-cl` instead of `cl.exe`
390 // * Build a project with `sccache`
391 // * Build for 32-bit as well
392 // * Build with Ninja
394 // For `cl.exe` there are different binaries to compile 32/64 bit which
395 // we use but for `clang-cl` there's only one which internally
396 // multiplexes via flags. As a result it appears that CMake's detection
397 // of a compiler's architecture and such on MSVC **doesn't** pass any
398 // custom flags we pass in CMAKE_CXX_FLAGS below. This means that if we
399 // use `clang-cl.exe` it's always diagnosed as a 64-bit compiler which
400 // definitely causes problems since all the env vars are pointing to
403 // To hack around this... again... we pass an argument that's
404 // unconditionally passed in the sccache shim. This'll get CMake to
405 // correctly diagnose it's doing a 32-bit compilation and LLVM will
406 // internally configure itself appropriately.
407 if builder.config.llvm_clang_cl.is_some() && target.contains("i686") {
408 cfg.env("SCCACHE_EXTRA_ARGS", "-m32");
411 // If ccache is configured we inform the build a little differently how
412 // to invoke ccache while also invoking our compilers.
413 if let Some(ref ccache) = builder.config.ccache {
414 cfg.define("CMAKE_C_COMPILER_LAUNCHER", ccache)
415 .define("CMAKE_CXX_COMPILER_LAUNCHER", ccache);
417 cfg.define("CMAKE_C_COMPILER", sanitize_cc(cc))
418 .define("CMAKE_CXX_COMPILER", sanitize_cc(cxx));
421 cfg.build_arg("-j").build_arg(builder.jobs().to_string());
422 let mut cflags = builder.cflags(target, GitRepo::Llvm).join(" ");
423 if let Some(ref s) = builder.config.llvm_cflags {
424 cflags.push_str(&format!(" {}", s));
426 cfg.define("CMAKE_C_FLAGS", cflags);
427 let mut cxxflags = builder.cflags(target, GitRepo::Llvm).join(" ");
428 if builder.config.llvm_static_stdcpp &&
429 !target.contains("windows") &&
430 !target.contains("netbsd")
432 cxxflags.push_str(" -static-libstdc++");
434 if let Some(ref s) = builder.config.llvm_cxxflags {
435 cxxflags.push_str(&format!(" {}", s));
437 cfg.define("CMAKE_CXX_FLAGS", cxxflags);
438 if let Some(ar) = builder.ar(target) {
439 if ar.is_absolute() {
440 // LLVM build breaks if `CMAKE_AR` is a relative path, for some reason it
441 // tries to resolve this path in the LLVM build directory.
442 cfg.define("CMAKE_AR", sanitize_cc(ar));
446 if let Some(ranlib) = builder.ranlib(target) {
447 if ranlib.is_absolute() {
448 // LLVM build breaks if `CMAKE_RANLIB` is a relative path, for some reason it
449 // tries to resolve this path in the LLVM build directory.
450 cfg.define("CMAKE_RANLIB", sanitize_cc(ranlib));
454 if let Some(ref s) = builder.config.llvm_ldflags {
455 cfg.define("CMAKE_SHARED_LINKER_FLAGS", s);
456 cfg.define("CMAKE_MODULE_LINKER_FLAGS", s);
457 cfg.define("CMAKE_EXE_LINKER_FLAGS", s);
460 if env::var_os("SCCACHE_ERROR_LOG").is_some() {
461 cfg.env("RUSTC_LOG", "sccache=warn");
465 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
467 pub target: Interned<String>,
471 type Output = PathBuf;
472 const ONLY_HOSTS: bool = true;
474 fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
475 run.path("src/llvm-project/lld").path("src/tools/lld")
478 fn make_run(run: RunConfig<'_>) {
479 run.builder.ensure(Lld { target: run.target });
482 /// Compile LLVM for `target`.
483 fn run(self, builder: &Builder<'_>) -> PathBuf {
484 if builder.config.dry_run {
485 return PathBuf::from("lld-out-dir-test-gen");
487 let target = self.target;
489 let llvm_config = builder.ensure(Llvm {
494 let out_dir = builder.lld_out(target);
495 let done_stamp = out_dir.join("lld-finished-building");
496 if done_stamp.exists() {
500 builder.info(&format!("Building LLD for {}", target));
501 let _time = util::timeit(&builder);
502 t!(fs::create_dir_all(&out_dir));
504 let mut cfg = cmake::Config::new(builder.src.join("src/llvm-project/lld"));
505 configure_cmake(builder, target, &mut cfg);
507 // This is an awful, awful hack. Discovered when we migrated to using
508 // clang-cl to compile LLVM/LLD it turns out that LLD, when built out of
509 // tree, will execute `llvm-config --cmakedir` and then tell CMake about
510 // that directory for later processing. Unfortunately if this path has
511 // forward slashes in it (which it basically always does on Windows)
512 // then CMake will hit a syntax error later on as... something isn't
515 // Instead of attempting to fix this problem in upstream CMake and/or
516 // LLVM/LLD we just hack around it here. This thin wrapper will take the
517 // output from llvm-config and replace all instances of `\` with `/` to
518 // ensure we don't hit the same bugs with escaping. It means that you
519 // can't build on a system where your paths require `\` on Windows, but
520 // there's probably a lot of reasons you can't do that other than this.
521 let llvm_config_shim = env::current_exe()
523 .with_file_name("llvm-config-wrapper");
524 cfg.out_dir(&out_dir)
526 .env("LLVM_CONFIG_REAL", llvm_config)
527 .define("LLVM_CONFIG_PATH", llvm_config_shim)
528 .define("LLVM_INCLUDE_TESTS", "OFF");
532 t!(File::create(&done_stamp));
537 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
538 pub struct TestHelpers {
539 pub target: Interned<String>,
542 impl Step for TestHelpers {
545 fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
546 run.path("src/test/auxiliary/rust_test_helpers.c")
549 fn make_run(run: RunConfig<'_>) {
550 run.builder.ensure(TestHelpers { target: run.target })
553 /// Compiles the `rust_test_helpers.c` library which we used in various
554 /// `run-pass` tests for ABI testing.
555 fn run(self, builder: &Builder<'_>) {
556 if builder.config.dry_run {
559 let target = self.target;
560 let dst = builder.test_helpers_out(target);
561 let src = builder.src.join("src/test/auxiliary/rust_test_helpers.c");
562 if up_to_date(&src, &dst.join("librust_test_helpers.a")) {
566 builder.info("Building test helpers");
567 t!(fs::create_dir_all(&dst));
568 let mut cfg = cc::Build::new();
570 // We may have found various cross-compilers a little differently due to our
571 // extra configuration, so inform gcc of these compilers. Note, though, that
572 // on MSVC we still need gcc's detection of env vars (ugh).
573 if !target.contains("msvc") {
574 if let Some(ar) = builder.ar(target) {
577 cfg.compiler(builder.cc(target));
580 cfg.cargo_metadata(false)
583 .host(&builder.config.build)
587 .file(builder.src.join("src/test/auxiliary/rust_test_helpers.c"))
588 .compile("rust_test_helpers");