| //! 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. |
| |
| use std::env; |
| use std::io; |
| use std::path::PathBuf; |
| use std::process::Command; |
| use std::str::FromStr; |
| use std::time::Instant; |
| |
| fn main() { |
| let args = env::args_os().skip(1).collect::<Vec<_>>(); |
| |
| // 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(Command::new); |
| |
| 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"); |
| } |
| } |
| } |
| |
| // 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"); |
| } |
| |
| if target.is_some() { |
| // 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); |
| } |
| |
| // 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. |
| // |
| // FIXME(rust-lang/cargo#7253) we should be doing this in `builder.rs` |
| // with env vars instead of doing it here in this script. |
| if crate_name == Some("compiler_builtins") { |
| cmd.arg("-C").arg("debug-assertions=no"); |
| } else { |
| cmd.arg("-C").arg(format!("debug-assertions={}", debug_assertions)); |
| } |
| } else { |
| // FIXME(rust-lang/cargo#5754) we shouldn't be using special env vars |
| // here, but rather Cargo should know what flags to pass rustc itself. |
| |
| // Override linker if necessary. |
| if let Ok(host_linker) = env::var("RUSTC_HOST_LINKER") { |
| cmd.arg(format!("-Clinker={}", host_linker)); |
| } |
| |
| // Override linker flavor if necessary. |
| if let Ok(host_linker_flavor) = env::var("RUSTC_HOST_LINKER_FLAVOR") { |
| cmd.arg(format!("-Clinker-flavor={}", host_linker_flavor)); |
| } |
| |
| 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 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_millis() |
| ); |
| |
| 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); |
| } |
| |
| #[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()) |
| } |