| //! Shim which is passed to Cargo as "rustc" when running the bootstrap. |
| //! |
| //! This shim will take care of some various tasks that our build process |
| //! requires that Cargo can't quite do through normal configuration: |
| //! |
| //! 1. When compiling build scripts and build dependencies, we need a guaranteed |
| //! full standard library available. The only compiler which actually has |
| //! this is the snapshot, so we detect this situation and always compile with |
| //! the snapshot compiler. |
| //! 2. We pass a bunch of `--cfg` and other flags based on what we're compiling |
| //! (and this slightly differs based on a whether we're using a snapshot or |
| //! not), so we do that all here. |
| //! |
| //! This may one day be replaced by RUSTFLAGS, but the dynamic nature of |
| //! switching compilers for the bootstrap and for build scripts will probably |
| //! never get replaced. |
| |
| // NO-RUSTC-WRAPPER |
| #![deny(warnings, rust_2018_idioms, unused_lifetimes)] |
| |
| use std::env; |
| use std::ffi::OsString; |
| use std::io; |
| use std::path::PathBuf; |
| use std::process::Command; |
| use std::str::FromStr; |
| use std::time::Instant; |
| |
| fn main() { |
| let mut args = env::args_os().skip(1).collect::<Vec<_>>(); |
| |
| // Append metadata suffix for internal crates. See the corresponding entry |
| // in bootstrap/lib.rs for details. |
| if let Ok(s) = env::var("RUSTC_METADATA_SUFFIX") { |
| for i in 1..args.len() { |
| // Dirty code for borrowing issues |
| let mut new = None; |
| if let Some(current_as_str) = args[i].to_str() { |
| if (&*args[i - 1] == "-C" && current_as_str.starts_with("metadata")) || |
| current_as_str.starts_with("-Cmetadata") { |
| new = Some(format!("{}-{}", current_as_str, s)); |
| } |
| } |
| if let Some(new) = new { args[i] = new.into(); } |
| } |
| } |
| |
| // Detect whether or not we're a build script depending on whether --target |
| // is passed (a bit janky...) |
| let target = args.windows(2) |
| .find(|w| &*w[0] == "--target") |
| .and_then(|w| w[1].to_str()); |
| let version = args.iter().find(|w| &**w == "-vV"); |
| |
| let verbose = match env::var("RUSTC_VERBOSE") { |
| Ok(s) => usize::from_str(&s).expect("RUSTC_VERBOSE should be an integer"), |
| Err(_) => 0, |
| }; |
| |
| // Use a different compiler for build scripts, since there may not yet be a |
| // libstd for the real compiler to use. However, if Cargo is attempting to |
| // determine the version of the compiler, the real compiler needs to be |
| // used. Currently, these two states are differentiated based on whether |
| // --target and -vV is/isn't passed. |
| let (rustc, libdir) = if target.is_none() && version.is_none() { |
| ("RUSTC_SNAPSHOT", "RUSTC_SNAPSHOT_LIBDIR") |
| } else { |
| ("RUSTC_REAL", "RUSTC_LIBDIR") |
| }; |
| let stage = env::var("RUSTC_STAGE").expect("RUSTC_STAGE was not set"); |
| let sysroot = env::var_os("RUSTC_SYSROOT").expect("RUSTC_SYSROOT was not set"); |
| let on_fail = env::var_os("RUSTC_ON_FAIL").map(|of| Command::new(of)); |
| |
| let rustc = env::var_os(rustc).unwrap_or_else(|| panic!("{:?} was not set", rustc)); |
| let libdir = env::var_os(libdir).unwrap_or_else(|| panic!("{:?} was not set", libdir)); |
| let mut dylib_path = bootstrap::util::dylib_path(); |
| dylib_path.insert(0, PathBuf::from(&libdir)); |
| |
| let mut cmd = Command::new(rustc); |
| cmd.args(&args) |
| .env(bootstrap::util::dylib_path_var(), |
| env::join_paths(&dylib_path).unwrap()); |
| |
| // Get the name of the crate we're compiling, if any. |
| let crate_name = args.windows(2) |
| .find(|args| args[0] == "--crate-name") |
| .and_then(|args| args[1].to_str()); |
| |
| if let Some(crate_name) = crate_name { |
| if let Some(target) = env::var_os("RUSTC_TIME") { |
| if target == "all" || |
| target.into_string().unwrap().split(",").any(|c| c.trim() == crate_name) |
| { |
| cmd.arg("-Ztime"); |
| } |
| } |
| } |
| |
| // Non-zero stages must all be treated uniformly to avoid problems when attempting to uplift |
| // compiler libraries and such from stage 1 to 2. |
| // |
| // FIXME: the fact that core here is excluded is due to core_arch from our stdarch submodule |
| // being broken on the beta compiler with bootstrap passed, so this is a temporary workaround |
| // (we've just snapped, so there are no cfg(bootstrap) related annotations in core). |
| if stage == "0" { |
| if crate_name != Some("core") { |
| cmd.arg("--cfg").arg("bootstrap"); |
| } else { |
| // NOTE(eddyb) see FIXME above, except now we need annotations again in core. |
| cmd.arg("--cfg").arg("boostrap_stdarch_ignore_this"); |
| } |
| } |
| |
| // Print backtrace in case of ICE |
| if env::var("RUSTC_BACKTRACE_ON_ICE").is_ok() && env::var("RUST_BACKTRACE").is_err() { |
| cmd.env("RUST_BACKTRACE", "1"); |
| } |
| |
| cmd.env("RUSTC_BREAK_ON_ICE", "1"); |
| |
| if let Ok(debuginfo_level) = env::var("RUSTC_DEBUGINFO_LEVEL") { |
| cmd.arg(format!("-Cdebuginfo={}", debuginfo_level)); |
| } |
| |
| if env::var_os("RUSTC_DENY_WARNINGS").is_some() && |
| env::var_os("RUSTC_EXTERNAL_TOOL").is_none() { |
| // When extending this list, search for `NO-RUSTC-WRAPPER` and add the new lints |
| // there as well, some code doesn't go through this `rustc` wrapper. |
| cmd.arg("-Dwarnings"); |
| cmd.arg("-Drust_2018_idioms"); |
| cmd.arg("-Dunused_lifetimes"); |
| if use_internal_lints(crate_name) { |
| cmd.arg("-Zunstable-options"); |
| cmd.arg("-Drustc::internal"); |
| } |
| } |
| |
| if let Some(target) = target { |
| // The stage0 compiler has a special sysroot distinct from what we |
| // actually downloaded, so we just always pass the `--sysroot` option, |
| // unless one is already set. |
| if !args.iter().any(|arg| arg == "--sysroot") { |
| cmd.arg("--sysroot").arg(&sysroot); |
| } |
| |
| cmd.arg("-Zexternal-macro-backtrace"); |
| |
| // Link crates to the proc macro crate for the target, but use a host proc macro crate |
| // to actually run the macros |
| if env::var_os("RUST_DUAL_PROC_MACROS").is_some() { |
| cmd.arg("-Zdual-proc-macros"); |
| } |
| |
| // When we build Rust dylibs they're all intended for intermediate |
| // usage, so make sure we pass the -Cprefer-dynamic flag instead of |
| // linking all deps statically into the dylib. |
| if env::var_os("RUSTC_NO_PREFER_DYNAMIC").is_none() { |
| cmd.arg("-Cprefer-dynamic"); |
| } |
| |
| // Help the libc crate compile by assisting it in finding various |
| // sysroot native libraries. |
| if let Some(s) = env::var_os("MUSL_ROOT") { |
| if target.contains("musl") { |
| let mut root = OsString::from("native="); |
| root.push(&s); |
| root.push("/lib"); |
| cmd.arg("-L").arg(&root); |
| } |
| } |
| if let Some(s) = env::var_os("WASI_ROOT") { |
| let mut root = OsString::from("native="); |
| root.push(&s); |
| root.push("/lib/wasm32-wasi"); |
| cmd.arg("-L").arg(&root); |
| } |
| |
| // Override linker if necessary. |
| if let Ok(target_linker) = env::var("RUSTC_TARGET_LINKER") { |
| cmd.arg(format!("-Clinker={}", target_linker)); |
| } |
| |
| // If we're compiling specifically the `panic_abort` crate then we pass |
| // the `-C panic=abort` option. Note that we do not do this for any |
| // other crate intentionally as this is the only crate for now that we |
| // ship with panic=abort. |
| // |
| // This... is a bit of a hack how we detect this. Ideally this |
| // information should be encoded in the crate I guess? Would likely |
| // require an RFC amendment to RFC 1513, however. |
| // |
| // `compiler_builtins` are unconditionally compiled with panic=abort to |
| // workaround undefined references to `rust_eh_unwind_resume` generated |
| // otherwise, see issue https://github.com/rust-lang/rust/issues/43095. |
| if crate_name == Some("panic_abort") || |
| crate_name == Some("compiler_builtins") && stage != "0" { |
| cmd.arg("-C").arg("panic=abort"); |
| } |
| |
| // Set various options from config.toml to configure how we're building |
| // code. |
| let debug_assertions = match env::var("RUSTC_DEBUG_ASSERTIONS") { |
| Ok(s) => if s == "true" { "y" } else { "n" }, |
| Err(..) => "n", |
| }; |
| |
| // The compiler builtins are pretty sensitive to symbols referenced in |
| // libcore and such, so we never compile them with debug assertions. |
| if crate_name == Some("compiler_builtins") { |
| cmd.arg("-C").arg("debug-assertions=no"); |
| } else { |
| cmd.arg("-C").arg(format!("debug-assertions={}", debug_assertions)); |
| } |
| |
| if let Ok(s) = env::var("RUSTC_CODEGEN_UNITS") { |
| cmd.arg("-C").arg(format!("codegen-units={}", s)); |
| } |
| |
| // Emit save-analysis info. |
| if env::var("RUSTC_SAVE_ANALYSIS") == Ok("api".to_string()) { |
| cmd.arg("-Zsave-analysis"); |
| cmd.env("RUST_SAVE_ANALYSIS_CONFIG", |
| "{\"output_file\": null,\"full_docs\": false,\ |
| \"pub_only\": true,\"reachable_only\": false,\ |
| \"distro_crate\": true,\"signatures\": false,\"borrow_data\": false}"); |
| } |
| |
| // Dealing with rpath here is a little special, so let's go into some |
| // detail. First off, `-rpath` is a linker option on Unix platforms |
| // which adds to the runtime dynamic loader path when looking for |
| // dynamic libraries. We use this by default on Unix platforms to ensure |
| // that our nightlies behave the same on Windows, that is they work out |
| // of the box. This can be disabled, of course, but basically that's why |
| // we're gated on RUSTC_RPATH here. |
| // |
| // Ok, so the astute might be wondering "why isn't `-C rpath` used |
| // here?" and that is indeed a good question to task. This codegen |
| // option is the compiler's current interface to generating an rpath. |
| // Unfortunately it doesn't quite suffice for us. The flag currently |
| // takes no value as an argument, so the compiler calculates what it |
| // should pass to the linker as `-rpath`. This unfortunately is based on |
| // the **compile time** directory structure which when building with |
| // Cargo will be very different than the runtime directory structure. |
| // |
| // All that's a really long winded way of saying that if we use |
| // `-Crpath` then the executables generated have the wrong rpath of |
| // something like `$ORIGIN/deps` when in fact the way we distribute |
| // rustc requires the rpath to be `$ORIGIN/../lib`. |
| // |
| // So, all in all, to set up the correct rpath we pass the linker |
| // argument manually via `-C link-args=-Wl,-rpath,...`. Plus isn't it |
| // fun to pass a flag to a tool to pass a flag to pass a flag to a tool |
| // to change a flag in a binary? |
| if env::var("RUSTC_RPATH") == Ok("true".to_string()) { |
| let rpath = if target.contains("apple") { |
| |
| // Note that we need to take one extra step on macOS to also pass |
| // `-Wl,-instal_name,@rpath/...` to get things to work right. To |
| // do that we pass a weird flag to the compiler to get it to do |
| // so. Note that this is definitely a hack, and we should likely |
| // flesh out rpath support more fully in the future. |
| cmd.arg("-Z").arg("osx-rpath-install-name"); |
| Some("-Wl,-rpath,@loader_path/../lib") |
| } else if !target.contains("windows") && |
| !target.contains("wasm32") && |
| !target.contains("fuchsia") { |
| Some("-Wl,-rpath,$ORIGIN/../lib") |
| } else { |
| None |
| }; |
| if let Some(rpath) = rpath { |
| cmd.arg("-C").arg(format!("link-args={}", rpath)); |
| } |
| } |
| |
| if let Ok(s) = env::var("RUSTC_CRT_STATIC") { |
| if s == "true" { |
| cmd.arg("-C").arg("target-feature=+crt-static"); |
| } |
| if s == "false" { |
| cmd.arg("-C").arg("target-feature=-crt-static"); |
| } |
| } |
| } else { |
| // Override linker if necessary. |
| if let Ok(host_linker) = env::var("RUSTC_HOST_LINKER") { |
| cmd.arg(format!("-Clinker={}", host_linker)); |
| } |
| |
| if let Ok(s) = env::var("RUSTC_HOST_CRT_STATIC") { |
| if s == "true" { |
| cmd.arg("-C").arg("target-feature=+crt-static"); |
| } |
| if s == "false" { |
| cmd.arg("-C").arg("target-feature=-crt-static"); |
| } |
| } |
| } |
| |
| if let Ok(map) = env::var("RUSTC_DEBUGINFO_MAP") { |
| cmd.arg("--remap-path-prefix").arg(&map); |
| } |
| |
| // Force all crates compiled by this compiler to (a) be unstable and (b) |
| // allow the `rustc_private` feature to link to other unstable crates |
| // also in the sysroot. We also do this for host crates, since those |
| // may be proc macros, in which case we might ship them. |
| if env::var_os("RUSTC_FORCE_UNSTABLE").is_some() && (stage != "0" || target.is_some()) { |
| cmd.arg("-Z").arg("force-unstable-if-unmarked"); |
| } |
| |
| if env::var_os("RUSTC_PARALLEL_COMPILER").is_some() { |
| cmd.arg("--cfg").arg("parallel_compiler"); |
| } |
| |
| if verbose > 1 { |
| eprintln!( |
| "rustc command: {:?}={:?} {:?}", |
| bootstrap::util::dylib_path_var(), |
| env::join_paths(&dylib_path).unwrap(), |
| cmd, |
| ); |
| eprintln!("sysroot: {:?}", sysroot); |
| eprintln!("libdir: {:?}", libdir); |
| } |
| |
| if let Some(mut on_fail) = on_fail { |
| let e = match cmd.status() { |
| Ok(s) if s.success() => std::process::exit(0), |
| e => e, |
| }; |
| println!("\nDid not run successfully: {:?}\n{:?}\n-------------", e, cmd); |
| exec_cmd(&mut on_fail).expect("could not run the backup command"); |
| std::process::exit(1); |
| } |
| |
| if env::var_os("RUSTC_PRINT_STEP_TIMINGS").is_some() { |
| if let Some(crate_name) = crate_name { |
| let start = Instant::now(); |
| let status = cmd |
| .status() |
| .unwrap_or_else(|_| panic!("\n\n failed to run {:?}", cmd)); |
| let dur = start.elapsed(); |
| |
| let is_test = args.iter().any(|a| a == "--test"); |
| eprintln!("[RUSTC-TIMING] {} test:{} {}.{:03}", |
| crate_name, |
| is_test, |
| dur.as_secs(), |
| dur.subsec_nanos() / 1_000_000); |
| |
| match status.code() { |
| Some(i) => std::process::exit(i), |
| None => { |
| eprintln!("rustc exited with {}", status); |
| std::process::exit(0xfe); |
| } |
| } |
| } |
| } |
| |
| let code = exec_cmd(&mut cmd).unwrap_or_else(|_| panic!("\n\n failed to run {:?}", cmd)); |
| std::process::exit(code); |
| } |
| |
| // Rustc crates for which internal lints are in effect. |
| fn use_internal_lints(crate_name: Option<&str>) -> bool { |
| crate_name.map_or(false, |crate_name| { |
| crate_name.starts_with("rustc") || crate_name.starts_with("syntax") || |
| ["arena", "fmt_macros"].contains(&crate_name) |
| }) |
| } |
| |
| #[cfg(unix)] |
| fn exec_cmd(cmd: &mut Command) -> io::Result<i32> { |
| use std::os::unix::process::CommandExt; |
| Err(cmd.exec()) |
| } |
| |
| #[cfg(not(unix))] |
| fn exec_cmd(cmd: &mut Command) -> io::Result<i32> { |
| cmd.status().map(|status| status.code().unwrap()) |
| } |