| //! 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::path::PathBuf; |
| use std::process::{Child, Command}; |
| use std::time::Instant; |
| |
| use dylib_util::{dylib_path, dylib_path_var}; |
| |
| #[path = "../utils/bin_helpers.rs"] |
| mod bin_helpers; |
| |
| #[path = "../utils/dylib.rs"] |
| mod dylib_util; |
| |
| fn main() { |
| let args = env::args_os().skip(1).collect::<Vec<_>>(); |
| let arg = |name| args.windows(2).find(|args| args[0] == name).and_then(|args| args[1].to_str()); |
| |
| // We don't use the stage in this shim, but let's parse it to make sure that we're invoked |
| // by bootstrap, or that we provide a helpful error message if not. |
| bin_helpers::parse_rustc_stage(); |
| let verbose = bin_helpers::parse_rustc_verbose(); |
| |
| // Detect whether or not we're a build script depending on whether --target |
| // is passed (a bit janky...) |
| let target = arg("--target"); |
| let version = args.iter().find(|w| &**w == "-vV"); |
| |
| // 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 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 = dylib_path(); |
| dylib_path.insert(0, PathBuf::from(&libdir)); |
| |
| let mut cmd = Command::new(rustc); |
| cmd.args(&args).env(dylib_path_var(), env::join_paths(&dylib_path).unwrap()); |
| |
| // Get the name of the crate we're compiling, if any. |
| let crate_name = arg("--crate-name"); |
| |
| 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-passes"); |
| } |
| } |
| } |
| |
| // 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 let Ok(lint_flags) = env::var("RUSTC_LINT_FLAGS") { |
| cmd.args(lint_flags.split_whitespace()); |
| } |
| |
| 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. |
| if crate_name == Some("panic_abort") { |
| cmd.arg("-C").arg("panic=abort"); |
| } |
| |
| // `-Ztls-model=initial-exec` must not be applied to proc-macros, see |
| // issue https://github.com/rust-lang/rust/issues/100530 |
| if env::var("RUSTC_TLS_MODEL_INITIAL_EXEC").is_ok() |
| && arg("--crate-type") != Some("proc-macro") |
| && !matches!(crate_name, Some("proc_macro2" | "quote" | "syn" | "synstructure")) |
| { |
| cmd.arg("-Ztls-model=initial-exec"); |
| } |
| } else { |
| // Find any host flags that were passed by bootstrap. |
| // The flags are stored in a RUSTC_HOST_FLAGS variable, separated by spaces. |
| if let Ok(flags) = std::env::var("RUSTC_HOST_FLAGS") { |
| for flag in flags.split(' ') { |
| cmd.arg(flag); |
| } |
| } |
| } |
| |
| if let Ok(map) = env::var("RUSTC_DEBUGINFO_MAP") { |
| cmd.arg("--remap-path-prefix").arg(&map); |
| } |
| // The remap flags for Cargo registry sources need to be passed after the remapping for the |
| // Rust source code directory, to handle cases when $CARGO_HOME is inside the source directory. |
| if let Ok(maps) = env::var("RUSTC_CARGO_REGISTRY_SRC_TO_REMAP") { |
| for map in maps.split('\t') { |
| 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() { |
| cmd.arg("-Z").arg("force-unstable-if-unmarked"); |
| } |
| |
| // allow-features is handled from within this rustc wrapper because of |
| // issues with build scripts. Some packages use build scripts to |
| // dynamically detect if certain nightly features are available. |
| // There are different ways this causes problems: |
| // |
| // * rustix runs `rustc` on a small test program to see if the feature is |
| // available (and sets a `cfg` if it is). It does not honor |
| // CARGO_ENCODED_RUSTFLAGS. |
| // * proc-macro2 detects if `rustc -vV` says "nighty" or "dev" and enables |
| // nightly features. It will scan CARGO_ENCODED_RUSTFLAGS for |
| // -Zallow-features. Unfortunately CARGO_ENCODED_RUSTFLAGS is not set |
| // for build-dependencies when --target is used. |
| // |
| // The issues above means we can't just use RUSTFLAGS, and we can't use |
| // `cargo -Zallow-features=…`. Passing it through here ensures that it |
| // always gets set. Unfortunately that also means we need to enable more |
| // features than we really want (like those for proc-macro2), but there |
| // isn't much of a way around it. |
| // |
| // I think it is unfortunate that build scripts are doing this at all, |
| // since changes to nightly features can cause crates to break even if the |
| // user didn't want or care about the use of the nightly features. I think |
| // nightly features should be opt-in only. Unfortunately the dynamic |
| // checks are now too wide spread that we just need to deal with it. |
| // |
| // If you want to try to remove this, I suggest working with the crate |
| // authors to remove the dynamic checking. Another option is to pursue |
| // https://github.com/rust-lang/cargo/issues/11244 and |
| // https://github.com/rust-lang/cargo/issues/4423, which will likely be |
| // very difficult, but could help expose -Zallow-features into build |
| // scripts so they could try to honor them. |
| if let Ok(allow_features) = env::var("RUSTC_ALLOW_FEATURES") { |
| cmd.arg(format!("-Zallow-features={allow_features}")); |
| } |
| |
| if let Ok(flags) = env::var("MAGIC_EXTRA_RUSTFLAGS") { |
| for flag in flags.split(' ') { |
| cmd.arg(flag); |
| } |
| } |
| |
| let is_test = args.iter().any(|a| a == "--test"); |
| if verbose > 2 { |
| let rust_env_vars = |
| env::vars().filter(|(k, _)| k.starts_with("RUST") || k.starts_with("CARGO")); |
| let prefix = if is_test { "[RUSTC-SHIM] rustc --test" } else { "[RUSTC-SHIM] rustc" }; |
| let prefix = match crate_name { |
| Some(crate_name) => format!("{prefix} {crate_name}"), |
| None => prefix.to_string(), |
| }; |
| for (i, (k, v)) in rust_env_vars.enumerate() { |
| eprintln!("{prefix} env[{i}]: {k:?}={v:?}"); |
| } |
| eprintln!("{} working directory: {}", prefix, env::current_dir().unwrap().display()); |
| eprintln!( |
| "{} command: {:?}={:?} {:?}", |
| prefix, |
| dylib_path_var(), |
| env::join_paths(&dylib_path).unwrap(), |
| cmd, |
| ); |
| eprintln!("{prefix} sysroot: {sysroot:?}"); |
| eprintln!("{prefix} libdir: {libdir:?}"); |
| } |
| |
| if env::var_os("RUSTC_BOLT_LINK_FLAGS").is_some() { |
| if let Some("rustc_driver") = crate_name { |
| cmd.arg("-Clink-args=-Wl,-q"); |
| } |
| } |
| |
| let start = Instant::now(); |
| let (child, status) = { |
| let errmsg = format!("\nFailed to run:\n{cmd:?}\n-------------"); |
| let mut child = cmd.spawn().expect(&errmsg); |
| let status = child.wait().expect(&errmsg); |
| (child, status) |
| }; |
| |
| if env::var_os("RUSTC_PRINT_STEP_TIMINGS").is_some() |
| || env::var_os("RUSTC_PRINT_STEP_RUSAGE").is_some() |
| { |
| if let Some(crate_name) = crate_name { |
| let dur = start.elapsed(); |
| // If the user requested resource usage data, then |
| // include that in addition to the timing output. |
| let rusage_data = |
| env::var_os("RUSTC_PRINT_STEP_RUSAGE").and_then(|_| format_rusage_data(child)); |
| eprintln!( |
| "[RUSTC-TIMING] {} test:{} {}.{:03}{}{}", |
| crate_name, |
| is_test, |
| dur.as_secs(), |
| dur.subsec_millis(), |
| if rusage_data.is_some() { " " } else { "" }, |
| rusage_data.unwrap_or(String::new()), |
| ); |
| } |
| } |
| |
| if status.success() { |
| std::process::exit(0); |
| // NOTE: everything below here is unreachable. do not put code that |
| // should run on success, after this block. |
| } |
| if verbose > 0 { |
| println!("\nDid not run successfully: {status}\n{cmd:?}\n-------------"); |
| } |
| |
| if let Some(mut on_fail) = on_fail { |
| on_fail.status().expect("Could not run the on_fail command"); |
| } |
| |
| // Preserve the exit code. In case of signal, exit with 0xfe since it's |
| // awkward to preserve this status in a cross-platform way. |
| match status.code() { |
| Some(i) => std::process::exit(i), |
| None => { |
| eprintln!("rustc exited with {status}"); |
| std::process::exit(0xfe); |
| } |
| } |
| } |
| |
| #[cfg(all(not(unix), not(windows)))] |
| // In the future we can add this for more platforms |
| fn format_rusage_data(_child: Child) -> Option<String> { |
| None |
| } |
| |
| #[cfg(windows)] |
| fn format_rusage_data(child: Child) -> Option<String> { |
| use std::os::windows::io::AsRawHandle; |
| |
| use windows::{ |
| Win32::Foundation::HANDLE, |
| Win32::System::ProcessStatus::{ |
| K32GetProcessMemoryInfo, PROCESS_MEMORY_COUNTERS, PROCESS_MEMORY_COUNTERS_EX, |
| }, |
| Win32::System::Threading::GetProcessTimes, |
| Win32::System::Time::FileTimeToSystemTime, |
| }; |
| |
| let handle = HANDLE(child.as_raw_handle() as isize); |
| |
| let mut user_filetime = Default::default(); |
| let mut user_time = Default::default(); |
| let mut kernel_filetime = Default::default(); |
| let mut kernel_time = Default::default(); |
| let mut memory_counters = PROCESS_MEMORY_COUNTERS::default(); |
| |
| unsafe { |
| GetProcessTimes( |
| handle, |
| &mut Default::default(), |
| &mut Default::default(), |
| &mut kernel_filetime, |
| &mut user_filetime, |
| ) |
| } |
| .ok()?; |
| unsafe { FileTimeToSystemTime(&user_filetime, &mut user_time) }.ok()?; |
| unsafe { FileTimeToSystemTime(&kernel_filetime, &mut kernel_time) }.ok()?; |
| |
| // Unlike on Linux with RUSAGE_CHILDREN, this will only return memory information for the process |
| // with the given handle and none of that process's children. |
| unsafe { |
| K32GetProcessMemoryInfo( |
| handle, |
| &mut memory_counters, |
| std::mem::size_of::<PROCESS_MEMORY_COUNTERS_EX>() as u32, |
| ) |
| } |
| .ok() |
| .ok()?; |
| |
| // Guide on interpreting these numbers: |
| // https://docs.microsoft.com/en-us/windows/win32/psapi/process-memory-usage-information |
| let peak_working_set = memory_counters.PeakWorkingSetSize / 1024; |
| let peak_page_file = memory_counters.PeakPagefileUsage / 1024; |
| let peak_paged_pool = memory_counters.QuotaPeakPagedPoolUsage / 1024; |
| let peak_nonpaged_pool = memory_counters.QuotaPeakNonPagedPoolUsage / 1024; |
| Some(format!( |
| "user: {USER_SEC}.{USER_USEC:03} \ |
| sys: {SYS_SEC}.{SYS_USEC:03} \ |
| peak working set (kb): {PEAK_WORKING_SET} \ |
| peak page file usage (kb): {PEAK_PAGE_FILE} \ |
| peak paged pool usage (kb): {PEAK_PAGED_POOL} \ |
| peak non-paged pool usage (kb): {PEAK_NONPAGED_POOL} \ |
| page faults: {PAGE_FAULTS}", |
| USER_SEC = user_time.wSecond + (user_time.wMinute * 60), |
| USER_USEC = user_time.wMilliseconds, |
| SYS_SEC = kernel_time.wSecond + (kernel_time.wMinute * 60), |
| SYS_USEC = kernel_time.wMilliseconds, |
| PEAK_WORKING_SET = peak_working_set, |
| PEAK_PAGE_FILE = peak_page_file, |
| PEAK_PAGED_POOL = peak_paged_pool, |
| PEAK_NONPAGED_POOL = peak_nonpaged_pool, |
| PAGE_FAULTS = memory_counters.PageFaultCount, |
| )) |
| } |
| |
| #[cfg(unix)] |
| /// Tries to build a string with human readable data for several of the rusage |
| /// fields. Note that we are focusing mainly on data that we believe to be |
| /// supplied on Linux (the `rusage` struct has other fields in it but they are |
| /// currently unsupported by Linux). |
| fn format_rusage_data(_child: Child) -> Option<String> { |
| let rusage: libc::rusage = unsafe { |
| let mut recv = std::mem::zeroed(); |
| // -1 is RUSAGE_CHILDREN, which means to get the rusage for all children |
| // (and grandchildren, etc) processes that have respectively terminated |
| // and been waited for. |
| let retval = libc::getrusage(-1, &mut recv); |
| if retval != 0 { |
| return None; |
| } |
| recv |
| }; |
| // Mac OS X reports the maxrss in bytes, not kb. |
| let divisor = if env::consts::OS == "macos" { 1024 } else { 1 }; |
| let maxrss = (rusage.ru_maxrss + (divisor - 1)) / divisor; |
| |
| let mut init_str = format!( |
| "user: {USER_SEC}.{USER_USEC:03} \ |
| sys: {SYS_SEC}.{SYS_USEC:03} \ |
| max rss (kb): {MAXRSS}", |
| USER_SEC = rusage.ru_utime.tv_sec, |
| USER_USEC = rusage.ru_utime.tv_usec, |
| SYS_SEC = rusage.ru_stime.tv_sec, |
| SYS_USEC = rusage.ru_stime.tv_usec, |
| MAXRSS = maxrss |
| ); |
| |
| // The remaining rusage stats vary in platform support. So we treat |
| // uniformly zero values in each category as "not worth printing", since it |
| // either means no events of that type occurred, or that the platform |
| // does not support it. |
| |
| let minflt = rusage.ru_minflt; |
| let majflt = rusage.ru_majflt; |
| if minflt != 0 || majflt != 0 { |
| init_str.push_str(&format!(" page reclaims: {minflt} page faults: {majflt}")); |
| } |
| |
| let inblock = rusage.ru_inblock; |
| let oublock = rusage.ru_oublock; |
| if inblock != 0 || oublock != 0 { |
| init_str.push_str(&format!(" fs block inputs: {inblock} fs block outputs: {oublock}")); |
| } |
| |
| let nvcsw = rusage.ru_nvcsw; |
| let nivcsw = rusage.ru_nivcsw; |
| if nvcsw != 0 || nivcsw != 0 { |
| init_str.push_str(&format!( |
| " voluntary ctxt switches: {nvcsw} involuntary ctxt switches: {nivcsw}" |
| )); |
| } |
| |
| return Some(init_str); |
| } |
