//! A library for [Cargo build scripts](https://doc.rust-lang.org/cargo/reference/build-scripts.html) //! to compile a set of C/C++/assembly/CUDA files into a static archive for Cargo //! to link into the crate being built. This crate does not compile code itself; //! it calls out to the default compiler for the platform. This crate will //! automatically detect situations such as cross compilation and //! [various environment variables](#external-configuration-via-environment-variables) and will build code appropriately. //! //! # Example //! //! First, you'll want to both add a build script for your crate (`build.rs`) and //! also add this crate to your `Cargo.toml` via: //! //! ```toml //! [build-dependencies] //! cc = "1.0" //! ``` //! //! Next up, you'll want to write a build script like so: //! //! ```rust,no_run //! // build.rs //! cc::Build::new() //! .file("foo.c") //! .file("bar.c") //! .compile("foo"); //! ``` //! //! And that's it! Running `cargo build` should take care of the rest and your Rust //! application will now have the C files `foo.c` and `bar.c` compiled into a file //! named `libfoo.a`. If the C files contain //! //! ```c //! void foo_function(void) { ... } //! ``` //! //! and //! //! ```c //! int32_t bar_function(int32_t x) { ... } //! ``` //! //! you can call them from Rust by declaring them in //! your Rust code like so: //! //! ```rust,no_run //! extern "C" { //! fn foo_function(); //! fn bar_function(x: i32) -> i32; //! } //! //! pub fn call() { //! unsafe { //! foo_function(); //! bar_function(42); //! } //! } //! //! fn main() { //! call(); //! } //! ``` //! //! See [the Rustonomicon](https://doc.rust-lang.org/nomicon/ffi.html) for more details. //! //! # External configuration via environment variables //! //! To control the programs and flags used for building, the builder can set a //! number of different environment variables. //! //! * `CFLAGS` - a series of space separated flags passed to compilers. Note that //! individual flags cannot currently contain spaces, so doing //! something like: `-L=foo\ bar` is not possible. //! * `CC` - the actual C compiler used. Note that this is used as an exact //! executable name, so (for example) no extra flags can be passed inside //! this variable, and the builder must ensure that there aren't any //! trailing spaces. This compiler must understand the `-c` flag. For //! certain `TARGET`s, it also is assumed to know about other flags (most //! common is `-fPIC`). //! * `AR` - the `ar` (archiver) executable to use to build the static library. //! * `CRATE_CC_NO_DEFAULTS` - the default compiler flags may cause conflicts in //! some cross compiling scenarios. Setting this variable //! will disable the generation of default compiler //! flags. //! * `CC_ENABLE_DEBUG_OUTPUT` - if set, compiler command invocations and exit codes will //! be logged to stdout. This is useful for debugging build script issues, but can be //! overly verbose for normal use. //! * `CC_SHELL_ESCAPED_FLAGS` - if set, `*FLAGS` will be parsed as if they were shell //! arguments (similar to `make` and `cmake`) rather than splitting them on each space. //! For example, with `CFLAGS='a "b c"'`, the compiler will be invoked with 2 arguments - //! `a` and `b c` - rather than 3: `a`, `"b` and `c"`. //! * `CXX...` - see [C++ Support](#c-support). //! * `CC_FORCE_DISABLE` - If set, `cc` will never run any [`Command`]s, and methods that //! would return an [`Error`]. This is intended for use by third-party build systems //! which want to be absolutely sure that they are in control of building all //! dependencies. Note that operations that return [`Tool`]s such as //! [`Build::get_compiler`] may produce less accurate results as in some cases `cc` runs //! commands in order to locate compilers. Additionally, this does nothing to prevent //! users from running [`Tool::to_command`] and executing the [`Command`] themselves.//! //! //! Furthermore, projects using this crate may specify custom environment variables //! to be inspected, for example via the `Build::try_flags_from_environment` //! function. Consult the project’s own documentation or its use of the `cc` crate //! for any additional variables it may use. //! //! Each of these variables can also be supplied with certain prefixes and suffixes, //! in the following prioritized order: //! //! 1. `_` - for example, `CC_x86_64-unknown-linux-gnu` //! 2. `_` - for example, `CC_x86_64_unknown_linux_gnu` //! 3. `_` - for example, `HOST_CC` or `TARGET_CFLAGS` //! 4. `` - a plain `CC`, `AR` as above. //! //! If none of these variables exist, cc-rs uses built-in defaults. //! //! In addition to the above optional environment variables, `cc-rs` has some //! functions with hard requirements on some variables supplied by [cargo's //! build-script driver][cargo] that it has the `TARGET`, `OUT_DIR`, `OPT_LEVEL`, //! and `HOST` variables. //! //! [cargo]: https://doc.rust-lang.org/cargo/reference/build-scripts.html#inputs-to-the-build-script //! //! # Optional features //! //! ## Parallel //! //! Currently cc-rs supports parallel compilation (think `make -jN`) but this //! feature is turned off by default. To enable cc-rs to compile C/C++ in parallel, //! you can change your dependency to: //! //! ```toml //! [build-dependencies] //! cc = { version = "1.0", features = ["parallel"] } //! ``` //! //! By default cc-rs will limit parallelism to `$NUM_JOBS`, or if not present it //! will limit it to the number of cpus on the machine. If you are using cargo, //! use `-jN` option of `build`, `test` and `run` commands as `$NUM_JOBS` //! is supplied by cargo. //! //! # Compile-time Requirements //! //! To work properly this crate needs access to a C compiler when the build script //! is being run. This crate does not ship a C compiler with it. The compiler //! required varies per platform, but there are three broad categories: //! //! * Unix platforms require `cc` to be the C compiler. This can be found by //! installing cc/clang on Linux distributions and Xcode on macOS, for example. //! * Windows platforms targeting MSVC (e.g. your target triple ends in `-msvc`) //! require Visual Studio to be installed. `cc-rs` attempts to locate it, and //! if it fails, `cl.exe` is expected to be available in `PATH`. This can be //! set up by running the appropriate developer tools shell. //! * Windows platforms targeting MinGW (e.g. your target triple ends in `-gnu`) //! require `cc` to be available in `PATH`. We recommend the //! [MinGW-w64](https://www.mingw-w64.org/) distribution. //! You may also acquire it via //! [MSYS2](https://www.msys2.org/), as explained [here][msys2-help]. Make sure //! to install the appropriate architecture corresponding to your installation of //! rustc. GCC from older [MinGW](http://www.mingw.org/) project is compatible //! only with 32-bit rust compiler. //! //! [msys2-help]: https://github.com/rust-lang/rust/blob/master/INSTALL.md#building-on-windows //! //! # C++ support //! //! `cc-rs` supports C++ libraries compilation by using the `cpp` method on //! `Build`: //! //! ```rust,no_run //! cc::Build::new() //! .cpp(true) // Switch to C++ library compilation. //! .file("foo.cpp") //! .compile("foo"); //! ``` //! //! For C++ libraries, the `CXX` and `CXXFLAGS` environment variables are used instead of `CC` and `CFLAGS`. //! //! The C++ standard library may be linked to the crate target. By default it's `libc++` for macOS, FreeBSD, and OpenBSD, `libc++_shared` for Android, nothing for MSVC, and `libstdc++` for anything else. It can be changed in one of two ways: //! //! 1. by using the `cpp_link_stdlib` method on `Build`: //! ```rust,no_run //! cc::Build::new() //! .cpp(true) //! .file("foo.cpp") //! .cpp_link_stdlib("stdc++") // use libstdc++ //! .compile("foo"); //! ``` //! 2. by setting the `CXXSTDLIB` environment variable. //! //! In particular, for Android you may want to [use `c++_static` if you have at most one shared library](https://developer.android.com/ndk/guides/cpp-support). //! //! Remember that C++ does name mangling so `extern "C"` might be required to enable Rust linker to find your functions. //! //! # CUDA C++ support //! //! `cc-rs` also supports compiling CUDA C++ libraries by using the `cuda` method //! on `Build`: //! //! ```rust,no_run //! cc::Build::new() //! // Switch to CUDA C++ library compilation using NVCC. //! .cuda(true) //! .cudart("static") //! // Generate code for Maxwell (GTX 970, 980, 980 Ti, Titan X). //! .flag("-gencode").flag("arch=compute_52,code=sm_52") //! // Generate code for Maxwell (Jetson TX1). //! .flag("-gencode").flag("arch=compute_53,code=sm_53") //! // Generate code for Pascal (GTX 1070, 1080, 1080 Ti, Titan Xp). //! .flag("-gencode").flag("arch=compute_61,code=sm_61") //! // Generate code for Pascal (Tesla P100). //! .flag("-gencode").flag("arch=compute_60,code=sm_60") //! // Generate code for Pascal (Jetson TX2). //! .flag("-gencode").flag("arch=compute_62,code=sm_62") //! // Generate code in parallel //! .flag("-t0") //! .file("bar.cu") //! .compile("bar"); //! ``` #![doc(html_root_url = "https://docs.rs/cc/1.0")] #![deny(warnings)] #![deny(missing_docs)] #![deny(clippy::disallowed_methods)] #![warn(clippy::doc_markdown)] use std::borrow::Cow; use std::collections::HashMap; use std::env; use std::ffi::{OsStr, OsString}; use std::fmt::{self, Display}; use std::fs; use std::io::{self, Write}; use std::path::{Component, Path, PathBuf}; #[cfg(feature = "parallel")] use std::process::Child; use std::process::Command; use std::sync::{ atomic::{AtomicU8, Ordering::Relaxed}, Arc, RwLock, }; use shlex::Shlex; #[cfg(feature = "parallel")] mod parallel; mod target; mod windows; use self::target::TargetInfo; // Regardless of whether this should be in this crate's public API, // it has been since 2015, so don't break it. pub use windows::find_tools as windows_registry; mod command_helpers; use command_helpers::*; mod tool; pub use tool::Tool; use tool::ToolFamily; mod tempfile; mod utilities; use utilities::*; mod flags; use flags::*; #[derive(Debug, Eq, PartialEq, Hash)] struct CompilerFlag { compiler: Box, flag: Box, } type Env = Option>; #[derive(Debug, Default)] struct BuildCache { env_cache: RwLock, Env>>, apple_sdk_root_cache: RwLock, Arc>>, apple_versions_cache: RwLock, Arc>>, cached_compiler_family: RwLock, ToolFamily>>, known_flag_support_status_cache: RwLock>, target_info_parser: target::TargetInfoParser, } /// A builder for compilation of a native library. /// /// A `Build` is the main type of the `cc` crate and is used to control all the /// various configuration options and such of a compile. You'll find more /// documentation on each method itself. #[derive(Clone, Debug)] pub struct Build { include_directories: Vec>, definitions: Vec<(Arc, Option>)>, objects: Vec>, flags: Vec>, flags_supported: Vec>, ar_flags: Vec>, asm_flags: Vec>, no_default_flags: bool, files: Vec>, cpp: bool, cpp_link_stdlib: Option>>, cpp_set_stdlib: Option>, cuda: bool, cudart: Option>, ccbin: bool, std: Option>, target: Option>, /// The host compiler. /// /// Try to not access this directly, and instead prefer `cfg!(...)`. host: Option>, out_dir: Option>, opt_level: Option>, debug: Option, force_frame_pointer: Option, env: Vec<(Arc, Arc)>, compiler: Option>, archiver: Option>, ranlib: Option>, cargo_output: CargoOutput, link_lib_modifiers: Vec>, pic: Option, use_plt: Option, static_crt: Option, shared_flag: Option, static_flag: Option, warnings_into_errors: bool, warnings: Option, extra_warnings: Option, emit_rerun_if_env_changed: bool, shell_escaped_flags: Option, build_cache: Arc, inherit_rustflags: bool, } /// Represents the types of errors that may occur while using cc-rs. #[derive(Clone, Debug)] enum ErrorKind { /// Error occurred while performing I/O. IOError, /// Environment variable not found, with the var in question as extra info. EnvVarNotFound, /// Error occurred while using external tools (ie: invocation of compiler). ToolExecError, /// Error occurred due to missing external tools. ToolNotFound, /// One of the function arguments failed validation. InvalidArgument, /// No known macro is defined for the compiler when discovering tool family. ToolFamilyMacroNotFound, /// Invalid target. InvalidTarget, /// Unknown target. UnknownTarget, /// Invalid rustc flag. InvalidFlag, #[cfg(feature = "parallel")] /// jobserver helpthread failure JobserverHelpThreadError, /// `cc` has been disabled by an environment variable. Disabled, } /// Represents an internal error that occurred, with an explanation. #[derive(Clone, Debug)] pub struct Error { /// Describes the kind of error that occurred. kind: ErrorKind, /// More explanation of error that occurred. message: Cow<'static, str>, } impl Error { fn new(kind: ErrorKind, message: impl Into>) -> Error { Error { kind, message: message.into(), } } } impl From for Error { fn from(e: io::Error) -> Error { Error::new(ErrorKind::IOError, format!("{}", e)) } } impl Display for Error { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { write!(f, "{:?}: {}", self.kind, self.message) } } impl std::error::Error for Error {} /// Represents an object. /// /// This is a source file -> object file pair. #[derive(Clone, Debug)] struct Object { src: PathBuf, dst: PathBuf, } impl Object { /// Create a new source file -> object file pair. fn new(src: PathBuf, dst: PathBuf) -> Object { Object { src, dst } } } impl Build { /// Construct a new instance of a blank set of configuration. /// /// This builder is finished with the [`compile`] function. /// /// [`compile`]: struct.Build.html#method.compile pub fn new() -> Build { Build { include_directories: Vec::new(), definitions: Vec::new(), objects: Vec::new(), flags: Vec::new(), flags_supported: Vec::new(), ar_flags: Vec::new(), asm_flags: Vec::new(), no_default_flags: false, files: Vec::new(), shared_flag: None, static_flag: None, cpp: false, cpp_link_stdlib: None, cpp_set_stdlib: None, cuda: false, cudart: None, ccbin: true, std: None, target: None, host: None, out_dir: None, opt_level: None, debug: None, force_frame_pointer: None, env: Vec::new(), compiler: None, archiver: None, ranlib: None, cargo_output: CargoOutput::new(), link_lib_modifiers: Vec::new(), pic: None, use_plt: None, static_crt: None, warnings: None, extra_warnings: None, warnings_into_errors: false, emit_rerun_if_env_changed: true, shell_escaped_flags: None, build_cache: Arc::default(), inherit_rustflags: true, } } /// Add a directory to the `-I` or include path for headers /// /// # Example /// /// ```no_run /// use std::path::Path; /// /// let library_path = Path::new("/path/to/library"); /// /// cc::Build::new() /// .file("src/foo.c") /// .include(library_path) /// .include("src") /// .compile("foo"); /// ``` pub fn include>(&mut self, dir: P) -> &mut Build { self.include_directories.push(dir.as_ref().into()); self } /// Add multiple directories to the `-I` include path. /// /// # Example /// /// ```no_run /// # use std::path::Path; /// # let condition = true; /// # /// let mut extra_dir = None; /// if condition { /// extra_dir = Some(Path::new("/path/to")); /// } /// /// cc::Build::new() /// .file("src/foo.c") /// .includes(extra_dir) /// .compile("foo"); /// ``` pub fn includes

(&mut self, dirs: P) -> &mut Build where P: IntoIterator, P::Item: AsRef, { for dir in dirs { self.include(dir); } self } /// Specify a `-D` variable with an optional value. /// /// # Example /// /// ```no_run /// cc::Build::new() /// .file("src/foo.c") /// .define("FOO", "BAR") /// .define("BAZ", None) /// .compile("foo"); /// ``` pub fn define<'a, V: Into>>(&mut self, var: &str, val: V) -> &mut Build { self.definitions .push((var.into(), val.into().map(Into::into))); self } /// Add an arbitrary object file to link in pub fn object>(&mut self, obj: P) -> &mut Build { self.objects.push(obj.as_ref().into()); self } /// Add arbitrary object files to link in pub fn objects

(&mut self, objs: P) -> &mut Build where P: IntoIterator, P::Item: AsRef, { for obj in objs { self.object(obj); } self } /// Add an arbitrary flag to the invocation of the compiler /// /// # Example /// /// ```no_run /// cc::Build::new() /// .file("src/foo.c") /// .flag("-ffunction-sections") /// .compile("foo"); /// ``` pub fn flag(&mut self, flag: impl AsRef) -> &mut Build { self.flags.push(flag.as_ref().into()); self } /// Removes a compiler flag that was added by [`Build::flag`]. /// /// Will not remove flags added by other means (default flags, /// flags from env, and so on). /// /// # Example /// ``` /// cc::Build::new() /// .file("src/foo.c") /// .flag("unwanted_flag") /// .remove_flag("unwanted_flag"); /// ``` pub fn remove_flag(&mut self, flag: &str) -> &mut Build { self.flags.retain(|other_flag| &**other_flag != flag); self } /// Add a flag to the invocation of the ar /// /// # Example /// /// ```no_run /// cc::Build::new() /// .file("src/foo.c") /// .file("src/bar.c") /// .ar_flag("/NODEFAULTLIB:libc.dll") /// .compile("foo"); /// ``` pub fn ar_flag(&mut self, flag: impl AsRef) -> &mut Build { self.ar_flags.push(flag.as_ref().into()); self } /// Add a flag that will only be used with assembly files. /// /// The flag will be applied to input files with either a `.s` or /// `.asm` extension (case insensitive). /// /// # Example /// /// ```no_run /// cc::Build::new() /// .asm_flag("-Wa,-defsym,abc=1") /// .file("src/foo.S") // The asm flag will be applied here /// .file("src/bar.c") // The asm flag will not be applied here /// .compile("foo"); /// ``` pub fn asm_flag(&mut self, flag: impl AsRef) -> &mut Build { self.asm_flags.push(flag.as_ref().into()); self } fn ensure_check_file(&self) -> Result { let out_dir = self.get_out_dir()?; let src = if self.cuda { assert!(self.cpp); out_dir.join("flag_check.cu") } else if self.cpp { out_dir.join("flag_check.cpp") } else { out_dir.join("flag_check.c") }; if !src.exists() { let mut f = fs::File::create(&src)?; write!(f, "int main(void) {{ return 0; }}")?; } Ok(src) } /// Run the compiler to test if it accepts the given flag. /// /// For a convenience method for setting flags conditionally, /// see `flag_if_supported()`. /// /// It may return error if it's unable to run the compiler with a test file /// (e.g. the compiler is missing or a write to the `out_dir` failed). /// /// Note: Once computed, the result of this call is stored in the /// `known_flag_support` field. If `is_flag_supported(flag)` /// is called again, the result will be read from the hash table. pub fn is_flag_supported(&self, flag: impl AsRef) -> Result { self.is_flag_supported_inner( flag.as_ref(), &self.get_base_compiler()?, &self.get_target()?, ) } fn is_flag_supported_inner( &self, flag: &OsStr, tool: &Tool, target: &TargetInfo<'_>, ) -> Result { let compiler_flag = CompilerFlag { compiler: tool.path().into(), flag: flag.into(), }; if let Some(is_supported) = self .build_cache .known_flag_support_status_cache .read() .unwrap() .get(&compiler_flag) .cloned() { return Ok(is_supported); } let out_dir = self.get_out_dir()?; let src = self.ensure_check_file()?; let obj = out_dir.join("flag_check"); let mut compiler = { let mut cfg = Build::new(); cfg.flag(flag) .compiler(tool.path()) .cargo_metadata(self.cargo_output.metadata) .opt_level(0) .debug(false) .cpp(self.cpp) .cuda(self.cuda) .inherit_rustflags(false) .emit_rerun_if_env_changed(self.emit_rerun_if_env_changed); if let Some(target) = &self.target { cfg.target(target); } if let Some(host) = &self.host { cfg.host(host); } cfg.try_get_compiler()? }; // Clang uses stderr for verbose output, which yields a false positive // result if the CFLAGS/CXXFLAGS include -v to aid in debugging. if compiler.family.verbose_stderr() { compiler.remove_arg("-v".into()); } if compiler.is_like_clang() { // Avoid reporting that the arg is unsupported just because the // compiler complains that it wasn't used. compiler.push_cc_arg("-Wno-unused-command-line-argument".into()); } let mut cmd = compiler.to_command(); let is_arm = matches!(target.arch, "aarch64" | "arm"); let clang = compiler.is_like_clang(); let gnu = compiler.family == ToolFamily::Gnu; command_add_output_file( &mut cmd, &obj, CmdAddOutputFileArgs { cuda: self.cuda, is_assembler_msvc: false, msvc: compiler.is_like_msvc(), clang, gnu, is_asm: false, is_arm, }, ); if compiler.supports_path_delimiter() { cmd.arg("--"); } cmd.arg(&src); // On MSVC skip the CRT by setting the entry point to `main`. // This way we don't need to add the default library paths. if compiler.is_like_msvc() { // Flags from _LINK_ are appended to the linker arguments. cmd.env("_LINK_", "-entry:main"); } let output = cmd.output()?; let is_supported = output.status.success() && output.stderr.is_empty(); self.build_cache .known_flag_support_status_cache .write() .unwrap() .insert(compiler_flag, is_supported); Ok(is_supported) } /// Add an arbitrary flag to the invocation of the compiler if it supports it /// /// # Example /// /// ```no_run /// cc::Build::new() /// .file("src/foo.c") /// .flag_if_supported("-Wlogical-op") // only supported by GCC /// .flag_if_supported("-Wunreachable-code") // only supported by clang /// .compile("foo"); /// ``` pub fn flag_if_supported(&mut self, flag: impl AsRef) -> &mut Build { self.flags_supported.push(flag.as_ref().into()); self } /// Add flags from the specified environment variable. /// /// Normally the `cc` crate will consult with the standard set of environment /// variables (such as `CFLAGS` and `CXXFLAGS`) to construct the compiler invocation. Use of /// this method provides additional levers for the end user to use when configuring the build /// process. /// /// Just like the standard variables, this method will search for an environment variable with /// appropriate target prefixes, when appropriate. /// /// # Examples /// /// This method is particularly beneficial in introducing the ability to specify crate-specific /// flags. /// /// ```no_run /// cc::Build::new() /// .file("src/foo.c") /// .try_flags_from_environment(concat!(env!("CARGO_PKG_NAME"), "_CFLAGS")) /// .expect("the environment variable must be specified and UTF-8") /// .compile("foo"); /// ``` /// pub fn try_flags_from_environment(&mut self, environ_key: &str) -> Result<&mut Build, Error> { let flags = self.envflags(environ_key)?; self.flags.extend( flags .into_iter() .map(|flag| Arc::from(OsString::from(flag).as_os_str())), ); Ok(self) } /// Set the `-shared` flag. /// /// When enabled, the compiler will produce a shared object which can /// then be linked with other objects to form an executable. /// /// # Example /// /// ```no_run /// cc::Build::new() /// .file("src/foo.c") /// .shared_flag(true) /// .compile("libfoo.so"); /// ``` pub fn shared_flag(&mut self, shared_flag: bool) -> &mut Build { self.shared_flag = Some(shared_flag); self } /// Set the `-static` flag. /// /// When enabled on systems that support dynamic linking, this prevents /// linking with the shared libraries. /// /// # Example /// /// ```no_run /// cc::Build::new() /// .file("src/foo.c") /// .shared_flag(true) /// .static_flag(true) /// .compile("foo"); /// ``` pub fn static_flag(&mut self, static_flag: bool) -> &mut Build { self.static_flag = Some(static_flag); self } /// Disables the generation of default compiler flags. The default compiler /// flags may cause conflicts in some cross compiling scenarios. /// /// Setting the `CRATE_CC_NO_DEFAULTS` environment variable has the same /// effect as setting this to `true`. The presence of the environment /// variable and the value of `no_default_flags` will be OR'd together. pub fn no_default_flags(&mut self, no_default_flags: bool) -> &mut Build { self.no_default_flags = no_default_flags; self } /// Add a file which will be compiled pub fn file>(&mut self, p: P) -> &mut Build { self.files.push(p.as_ref().into()); self } /// Add files which will be compiled pub fn files

(&mut self, p: P) -> &mut Build where P: IntoIterator, P::Item: AsRef, { for file in p.into_iter() { self.file(file); } self } /// Get the files which will be compiled pub fn get_files(&self) -> impl Iterator { self.files.iter().map(AsRef::as_ref) } /// Set C++ support. /// /// The other `cpp_*` options will only become active if this is set to /// `true`. /// /// The name of the C++ standard library to link is decided by: /// 1. If [`cpp_link_stdlib`](Build::cpp_link_stdlib) is set, use its value. /// 2. Else if the `CXXSTDLIB` environment variable is set, use its value. /// 3. Else the default is `c++` for OS X and BSDs, `c++_shared` for Android, /// `None` for MSVC and `stdc++` for anything else. pub fn cpp(&mut self, cpp: bool) -> &mut Build { self.cpp = cpp; self } /// Set CUDA C++ support. /// /// Enabling CUDA will invoke the CUDA compiler, NVCC. While NVCC accepts /// the most common compiler flags, e.g. `-std=c++17`, some project-specific /// flags might have to be prefixed with "-Xcompiler" flag, for example as /// `.flag("-Xcompiler").flag("-fpermissive")`. See the documentation for /// `nvcc`, the CUDA compiler driver, at /// for more information. /// /// If enabled, this also implicitly enables C++ support. pub fn cuda(&mut self, cuda: bool) -> &mut Build { self.cuda = cuda; if cuda { self.cpp = true; self.cudart = Some("static".into()); } self } /// Link CUDA run-time. /// /// This option mimics the `--cudart` NVCC command-line option. Just like /// the original it accepts `{none|shared|static}`, with default being /// `static`. The method has to be invoked after `.cuda(true)`, or not /// at all, if the default is right for the project. pub fn cudart(&mut self, cudart: &str) -> &mut Build { if self.cuda { self.cudart = Some(cudart.into()); } self } /// Set CUDA host compiler. /// /// By default, a `-ccbin` flag will be passed to NVCC to specify the /// underlying host compiler. The value of `-ccbin` is the same as the /// chosen C++ compiler. This is not always desired, because NVCC might /// not support that compiler. In this case, you can remove the `-ccbin` /// flag so that NVCC will choose the host compiler by itself. pub fn ccbin(&mut self, ccbin: bool) -> &mut Build { self.ccbin = ccbin; self } /// Specify the C or C++ language standard version. /// /// These values are common to modern versions of GCC, Clang and MSVC: /// - `c11` for ISO/IEC 9899:2011 /// - `c17` for ISO/IEC 9899:2018 /// - `c++14` for ISO/IEC 14882:2014 /// - `c++17` for ISO/IEC 14882:2017 /// - `c++20` for ISO/IEC 14882:2020 /// /// Other values have less broad support, e.g. MSVC does not support `c++11` /// (`c++14` is the minimum), `c89` (omit the flag instead) or `c99`. /// /// For compiling C++ code, you should also set `.cpp(true)`. /// /// The default is that no standard flag is passed to the compiler, so the /// language version will be the compiler's default. /// /// # Example /// /// ```no_run /// cc::Build::new() /// .file("src/modern.cpp") /// .cpp(true) /// .std("c++17") /// .compile("modern"); /// ``` pub fn std(&mut self, std: &str) -> &mut Build { self.std = Some(std.into()); self } /// Set warnings into errors flag. /// /// Disabled by default. /// /// Warning: turning warnings into errors only make sense /// if you are a developer of the crate using cc-rs. /// Some warnings only appear on some architecture or /// specific version of the compiler. Any user of this crate, /// or any other crate depending on it, could fail during /// compile time. /// /// # Example /// /// ```no_run /// cc::Build::new() /// .file("src/foo.c") /// .warnings_into_errors(true) /// .compile("libfoo.a"); /// ``` pub fn warnings_into_errors(&mut self, warnings_into_errors: bool) -> &mut Build { self.warnings_into_errors = warnings_into_errors; self } /// Set warnings flags. /// /// Adds some flags: /// - "-Wall" for MSVC. /// - "-Wall", "-Wextra" for GNU and Clang. /// /// Enabled by default. /// /// # Example /// /// ```no_run /// cc::Build::new() /// .file("src/foo.c") /// .warnings(false) /// .compile("libfoo.a"); /// ``` pub fn warnings(&mut self, warnings: bool) -> &mut Build { self.warnings = Some(warnings); self.extra_warnings = Some(warnings); self } /// Set extra warnings flags. /// /// Adds some flags: /// - nothing for MSVC. /// - "-Wextra" for GNU and Clang. /// /// Enabled by default. /// /// # Example /// /// ```no_run /// // Disables -Wextra, -Wall remains enabled: /// cc::Build::new() /// .file("src/foo.c") /// .extra_warnings(false) /// .compile("libfoo.a"); /// ``` pub fn extra_warnings(&mut self, warnings: bool) -> &mut Build { self.extra_warnings = Some(warnings); self } /// Set the standard library to link against when compiling with C++ /// support. /// /// If the `CXXSTDLIB` environment variable is set, its value will /// override the default value, but not the value explicitly set by calling /// this function. /// /// A value of `None` indicates that no automatic linking should happen, /// otherwise cargo will link against the specified library. /// /// The given library name must not contain the `lib` prefix. /// /// Common values: /// - `stdc++` for GNU /// - `c++` for Clang /// - `c++_shared` or `c++_static` for Android /// /// # Example /// /// ```no_run /// cc::Build::new() /// .file("src/foo.c") /// .shared_flag(true) /// .cpp_link_stdlib("stdc++") /// .compile("libfoo.so"); /// ``` pub fn cpp_link_stdlib<'a, V: Into>>( &mut self, cpp_link_stdlib: V, ) -> &mut Build { self.cpp_link_stdlib = Some(cpp_link_stdlib.into().map(Arc::from)); self } /// Force the C++ compiler to use the specified standard library. /// /// Setting this option will automatically set `cpp_link_stdlib` to the same /// value. /// /// The default value of this option is always `None`. /// /// This option has no effect when compiling for a Visual Studio based /// target. /// /// This option sets the `-stdlib` flag, which is only supported by some /// compilers (clang, icc) but not by others (gcc). The library will not /// detect which compiler is used, as such it is the responsibility of the /// caller to ensure that this option is only used in conjunction with a /// compiler which supports the `-stdlib` flag. /// /// A value of `None` indicates that no specific C++ standard library should /// be used, otherwise `-stdlib` is added to the compile invocation. /// /// The given library name must not contain the `lib` prefix. /// /// Common values: /// - `stdc++` for GNU /// - `c++` for Clang /// /// # Example /// /// ```no_run /// cc::Build::new() /// .file("src/foo.c") /// .cpp_set_stdlib("c++") /// .compile("libfoo.a"); /// ``` pub fn cpp_set_stdlib<'a, V: Into>>( &mut self, cpp_set_stdlib: V, ) -> &mut Build { let cpp_set_stdlib = cpp_set_stdlib.into().map(Arc::from); self.cpp_set_stdlib.clone_from(&cpp_set_stdlib); self.cpp_link_stdlib = Some(cpp_set_stdlib); self } /// Configures the `rustc` target this configuration will be compiling /// for. /// /// This will fail if using a target not in a pre-compiled list taken from /// `rustc +nightly --print target-list`. The list will be updated /// periodically. /// /// You should avoid setting this in build scripts, target information /// will instead be retrieved from the environment variables `TARGET` and /// `CARGO_CFG_TARGET_*` that Cargo sets. /// /// # Example /// /// ```no_run /// cc::Build::new() /// .file("src/foo.c") /// .target("aarch64-linux-android") /// .compile("foo"); /// ``` pub fn target(&mut self, target: &str) -> &mut Build { self.target = Some(target.into()); self } /// Configures the host assumed by this configuration. /// /// This option is automatically scraped from the `HOST` environment /// variable by build scripts, so it's not required to call this function. /// /// # Example /// /// ```no_run /// cc::Build::new() /// .file("src/foo.c") /// .host("arm-linux-gnueabihf") /// .compile("foo"); /// ``` pub fn host(&mut self, host: &str) -> &mut Build { self.host = Some(host.into()); self } /// Configures the optimization level of the generated object files. /// /// This option is automatically scraped from the `OPT_LEVEL` environment /// variable by build scripts, so it's not required to call this function. pub fn opt_level(&mut self, opt_level: u32) -> &mut Build { self.opt_level = Some(opt_level.to_string().into()); self } /// Configures the optimization level of the generated object files. /// /// This option is automatically scraped from the `OPT_LEVEL` environment /// variable by build scripts, so it's not required to call this function. pub fn opt_level_str(&mut self, opt_level: &str) -> &mut Build { self.opt_level = Some(opt_level.into()); self } /// Configures whether the compiler will emit debug information when /// generating object files. /// /// This option is automatically scraped from the `DEBUG` environment /// variable by build scripts, so it's not required to call this function. pub fn debug(&mut self, debug: bool) -> &mut Build { self.debug = Some(debug); self } /// Configures whether the compiler will emit instructions to store /// frame pointers during codegen. /// /// This option is automatically enabled when debug information is emitted. /// Otherwise the target platform compiler's default will be used. /// You can use this option to force a specific setting. pub fn force_frame_pointer(&mut self, force: bool) -> &mut Build { self.force_frame_pointer = Some(force); self } /// Configures the output directory where all object files and static /// libraries will be located. /// /// This option is automatically scraped from the `OUT_DIR` environment /// variable by build scripts, so it's not required to call this function. pub fn out_dir>(&mut self, out_dir: P) -> &mut Build { self.out_dir = Some(out_dir.as_ref().into()); self } /// Configures the compiler to be used to produce output. /// /// This option is automatically determined from the target platform or a /// number of environment variables, so it's not required to call this /// function. pub fn compiler>(&mut self, compiler: P) -> &mut Build { self.compiler = Some(compiler.as_ref().into()); self } /// Configures the tool used to assemble archives. /// /// This option is automatically determined from the target platform or a /// number of environment variables, so it's not required to call this /// function. pub fn archiver>(&mut self, archiver: P) -> &mut Build { self.archiver = Some(archiver.as_ref().into()); self } /// Configures the tool used to index archives. /// /// This option is automatically determined from the target platform or a /// number of environment variables, so it's not required to call this /// function. pub fn ranlib>(&mut self, ranlib: P) -> &mut Build { self.ranlib = Some(ranlib.as_ref().into()); self } /// Define whether metadata should be emitted for cargo allowing it to /// automatically link the binary. Defaults to `true`. /// /// The emitted metadata is: /// /// - `rustc-link-lib=static=`*compiled lib* /// - `rustc-link-search=native=`*target folder* /// - When target is MSVC, the ATL-MFC libs are added via `rustc-link-search=native=` /// - When C++ is enabled, the C++ stdlib is added via `rustc-link-lib` /// - If `emit_rerun_if_env_changed` is not `false`, `rerun-if-env-changed=`*env* /// pub fn cargo_metadata(&mut self, cargo_metadata: bool) -> &mut Build { self.cargo_output.metadata = cargo_metadata; self } /// Define whether compile warnings should be emitted for cargo. Defaults to /// `true`. /// /// If disabled, compiler messages will not be printed. /// Issues unrelated to the compilation will always produce cargo warnings regardless of this setting. pub fn cargo_warnings(&mut self, cargo_warnings: bool) -> &mut Build { self.cargo_output.warnings = cargo_warnings; self } /// Define whether debug information should be emitted for cargo. Defaults to whether /// or not the environment variable `CC_ENABLE_DEBUG_OUTPUT` is set. /// /// If enabled, the compiler will emit debug information when generating object files, /// such as the command invoked and the exit status. pub fn cargo_debug(&mut self, cargo_debug: bool) -> &mut Build { self.cargo_output.debug = cargo_debug; self } /// Define whether compiler output (to stdout) should be emitted. Defaults to `true` /// (forward compiler stdout to this process' stdout) /// /// Some compilers emit errors to stdout, so if you *really* need stdout to be clean /// you should also set this to `false`. pub fn cargo_output(&mut self, cargo_output: bool) -> &mut Build { self.cargo_output.output = if cargo_output { OutputKind::Forward } else { OutputKind::Discard }; self } /// Adds a native library modifier that will be added to the /// `rustc-link-lib=static:MODIFIERS=LIBRARY_NAME` metadata line /// emitted for cargo if `cargo_metadata` is enabled. /// See /// for the list of modifiers accepted by rustc. pub fn link_lib_modifier(&mut self, link_lib_modifier: impl AsRef) -> &mut Build { self.link_lib_modifiers .push(link_lib_modifier.as_ref().into()); self } /// Configures whether the compiler will emit position independent code. /// /// This option defaults to `false` for `windows-gnu` and bare metal targets and /// to `true` for all other targets. pub fn pic(&mut self, pic: bool) -> &mut Build { self.pic = Some(pic); self } /// Configures whether the Procedure Linkage Table is used for indirect /// calls into shared libraries. /// /// The PLT is used to provide features like lazy binding, but introduces /// a small performance loss due to extra pointer indirection. Setting /// `use_plt` to `false` can provide a small performance increase. /// /// Note that skipping the PLT requires a recent version of GCC/Clang. /// /// This only applies to ELF targets. It has no effect on other platforms. pub fn use_plt(&mut self, use_plt: bool) -> &mut Build { self.use_plt = Some(use_plt); self } /// Define whether metadata should be emitted for cargo to detect environment /// changes that should trigger a rebuild. /// /// NOTE that cc does not emit metadata to detect changes for `PATH`, since it could /// be changed every comilation yet does not affect the result of compilation /// (i.e. rust-analyzer adds temporary directory to `PATH`). /// /// cc in general, has no way detecting changes to compiler, as there are so many ways to /// change it and sidestep the detection, for example the compiler might be wrapped in a script /// so detecting change of the file, or using checksum won't work. /// /// We recommend users to decide for themselves, if they want rebuild if the compiler has been upgraded /// or changed, and how to detect that. /// /// This has no effect if the `cargo_metadata` option is `false`. /// /// This option defaults to `true`. pub fn emit_rerun_if_env_changed(&mut self, emit_rerun_if_env_changed: bool) -> &mut Build { self.emit_rerun_if_env_changed = emit_rerun_if_env_changed; self } /// Configures whether the /MT flag or the /MD flag will be passed to msvc build tools. /// /// This option defaults to `false`, and affect only msvc targets. pub fn static_crt(&mut self, static_crt: bool) -> &mut Build { self.static_crt = Some(static_crt); self } /// Configure whether *FLAGS variables are parsed using `shlex`, similarly to `make` and /// `cmake`. /// /// This option defaults to `false`. pub fn shell_escaped_flags(&mut self, shell_escaped_flags: bool) -> &mut Build { self.shell_escaped_flags = Some(shell_escaped_flags); self } /// Configure whether cc should automatically inherit compatible flags passed to rustc /// from `CARGO_ENCODED_RUSTFLAGS`. /// /// This option defaults to `true`. pub fn inherit_rustflags(&mut self, inherit_rustflags: bool) -> &mut Build { self.inherit_rustflags = inherit_rustflags; self } #[doc(hidden)] pub fn __set_env(&mut self, a: A, b: B) -> &mut Build where A: AsRef, B: AsRef, { self.env.push((a.as_ref().into(), b.as_ref().into())); self } /// Run the compiler, generating the file `output` /// /// This will return a result instead of panicking; see [`Self::compile()`] for /// the complete description. pub fn try_compile(&self, output: &str) -> Result<(), Error> { let mut output_components = Path::new(output).components(); match (output_components.next(), output_components.next()) { (Some(Component::Normal(_)), None) => {} _ => { return Err(Error::new( ErrorKind::InvalidArgument, "argument of `compile` must be a single normal path component", )); } } let (lib_name, gnu_lib_name) = if output.starts_with("lib") && output.ends_with(".a") { (&output[3..output.len() - 2], output.to_owned()) } else { let mut gnu = String::with_capacity(5 + output.len()); gnu.push_str("lib"); gnu.push_str(output); gnu.push_str(".a"); (output, gnu) }; let dst = self.get_out_dir()?; let objects = objects_from_files(&self.files, &dst)?; self.compile_objects(&objects)?; self.assemble(lib_name, &dst.join(gnu_lib_name), &objects)?; let target = self.get_target()?; if target.env == "msvc" { let compiler = self.get_base_compiler()?; let atlmfc_lib = compiler .env() .iter() .find(|&(var, _)| var.as_os_str() == OsStr::new("LIB")) .and_then(|(_, lib_paths)| { env::split_paths(lib_paths).find(|path| { let sub = Path::new("atlmfc/lib"); path.ends_with(sub) || path.parent().map_or(false, |p| p.ends_with(sub)) }) }); if let Some(atlmfc_lib) = atlmfc_lib { self.cargo_output.print_metadata(&format_args!( "cargo:rustc-link-search=native={}", atlmfc_lib.display() )); } } if self.link_lib_modifiers.is_empty() { self.cargo_output .print_metadata(&format_args!("cargo:rustc-link-lib=static={}", lib_name)); } else { self.cargo_output.print_metadata(&format_args!( "cargo:rustc-link-lib=static:{}={}", JoinOsStrs { slice: &self.link_lib_modifiers, delimiter: ',' }, lib_name )); } self.cargo_output.print_metadata(&format_args!( "cargo:rustc-link-search=native={}", dst.display() )); // Add specific C++ libraries, if enabled. if self.cpp { if let Some(stdlib) = self.get_cpp_link_stdlib()? { self.cargo_output .print_metadata(&format_args!("cargo:rustc-link-lib={}", stdlib.display())); } // Link c++ lib from WASI sysroot if target.os == "wasi" { if let Ok(wasi_sysroot) = self.wasi_sysroot() { self.cargo_output.print_metadata(&format_args!( "cargo:rustc-flags=-L {}/lib/{} -lstatic=c++ -lstatic=c++abi", Path::new(&wasi_sysroot).display(), self.get_raw_target()? )); } } } let cudart = match &self.cudart { Some(opt) => opt, // {none|shared|static} None => "none", }; if cudart != "none" { if let Some(nvcc) = self.which(&self.get_compiler().path, None) { // Try to figure out the -L search path. If it fails, // it's on user to specify one by passing it through // RUSTFLAGS environment variable. let mut libtst = false; let mut libdir = nvcc; libdir.pop(); // remove 'nvcc' libdir.push(".."); if cfg!(target_os = "linux") { libdir.push("targets"); libdir.push(format!("{}-linux", target.arch)); libdir.push("lib"); libtst = true; } else if cfg!(target_env = "msvc") { libdir.push("lib"); match target.arch { "x86_64" => { libdir.push("x64"); libtst = true; } "x86" => { libdir.push("Win32"); libtst = true; } _ => libtst = false, } } if libtst && libdir.is_dir() { self.cargo_output.print_metadata(&format_args!( "cargo:rustc-link-search=native={}", libdir.to_str().unwrap() )); } // And now the -l flag. let lib = match cudart { "shared" => "cudart", "static" => "cudart_static", bad => panic!("unsupported cudart option: {}", bad), }; self.cargo_output .print_metadata(&format_args!("cargo:rustc-link-lib={}", lib)); } } Ok(()) } /// Run the compiler, generating the file `output` /// /// # Library name /// /// The `output` string argument determines the file name for the compiled /// library. The Rust compiler will create an assembly named "lib"+output+".a". /// MSVC will create a file named output+".lib". /// /// The choice of `output` is close to arbitrary, but: /// /// - must be nonempty, /// - must not contain a path separator (`/`), /// - must be unique across all `compile` invocations made by the same build /// script. /// /// If your build script compiles a single source file, the base name of /// that source file would usually be reasonable: /// /// ```no_run /// cc::Build::new().file("blobstore.c").compile("blobstore"); /// ``` /// /// Compiling multiple source files, some people use their crate's name, or /// their crate's name + "-cc". /// /// Otherwise, please use your imagination. /// /// For backwards compatibility, if `output` starts with "lib" *and* ends /// with ".a", a second "lib" prefix and ".a" suffix do not get added on, /// but this usage is deprecated; please omit `lib` and `.a` in the argument /// that you pass. /// /// # Panics /// /// Panics if `output` is not formatted correctly or if one of the underlying /// compiler commands fails. It can also panic if it fails reading file names /// or creating directories. pub fn compile(&self, output: &str) { if let Err(e) = self.try_compile(output) { fail(&e.message); } } /// Run the compiler, generating intermediate files, but without linking /// them into an archive file. /// /// This will return a list of compiled object files, in the same order /// as they were passed in as `file`/`files` methods. pub fn compile_intermediates(&self) -> Vec { match self.try_compile_intermediates() { Ok(v) => v, Err(e) => fail(&e.message), } } /// Run the compiler, generating intermediate files, but without linking /// them into an archive file. /// /// This will return a result instead of panicking; see `compile_intermediates()` for the complete description. pub fn try_compile_intermediates(&self) -> Result, Error> { let dst = self.get_out_dir()?; let objects = objects_from_files(&self.files, &dst)?; self.compile_objects(&objects)?; Ok(objects.into_iter().map(|v| v.dst).collect()) } #[cfg(feature = "parallel")] fn compile_objects(&self, objs: &[Object]) -> Result<(), Error> { use std::cell::Cell; use parallel::async_executor::{block_on, YieldOnce}; check_disabled()?; if objs.len() <= 1 { for obj in objs { let (mut cmd, name) = self.create_compile_object_cmd(obj)?; run(&mut cmd, &name, &self.cargo_output)?; } return Ok(()); } // Limit our parallelism globally with a jobserver. let mut tokens = parallel::job_token::ActiveJobTokenServer::new(); // When compiling objects in parallel we do a few dirty tricks to speed // things up: // // * First is that we use the `jobserver` crate to limit the parallelism // of this build script. The `jobserver` crate will use a jobserver // configured by Cargo for build scripts to ensure that parallelism is // coordinated across C compilations and Rust compilations. Before we // compile anything we make sure to wait until we acquire a token. // // Note that this jobserver is cached globally so we only used one per // process and only worry about creating it once. // // * Next we use spawn the process to actually compile objects in // parallel after we've acquired a token to perform some work // // With all that in mind we compile all objects in a loop here, after we // acquire the appropriate tokens, Once all objects have been compiled // we wait on all the processes and propagate the results of compilation. let pendings = Cell::new(Vec::<( Command, Cow<'static, Path>, KillOnDrop, parallel::job_token::JobToken, )>::new()); let is_disconnected = Cell::new(false); let has_made_progress = Cell::new(false); let wait_future = async { let mut error = None; // Buffer the stdout let mut stdout = io::BufWriter::with_capacity(128, io::stdout()); loop { // If the other end of the pipe is already disconnected, then we're not gonna get any new jobs, // so it doesn't make sense to reuse the tokens; in fact, // releasing them as soon as possible (once we know that the other end is disconnected) is beneficial. // Imagine that the last file built takes an hour to finish; in this scenario, // by not releasing the tokens before that last file is done we would effectively block other processes from // starting sooner - even though we only need one token for that last file, not N others that were acquired. let mut pendings_is_empty = false; cell_update(&pendings, |mut pendings| { // Try waiting on them. pendings.retain_mut(|(cmd, program, child, _token)| { match try_wait_on_child( cmd, program, &mut child.0, &mut stdout, &mut child.1, ) { Ok(Some(())) => { // Task done, remove the entry has_made_progress.set(true); false } Ok(None) => true, // Task still not finished, keep the entry Err(err) => { // Task fail, remove the entry. // Since we can only return one error, log the error to make // sure users always see all the compilation failures. has_made_progress.set(true); if self.cargo_output.warnings { let _ = writeln!(stdout, "cargo:warning={}", err); } error = Some(err); false } } }); pendings_is_empty = pendings.is_empty(); pendings }); if pendings_is_empty && is_disconnected.get() { break if let Some(err) = error { Err(err) } else { Ok(()) }; } YieldOnce::default().await; } }; let spawn_future = async { for obj in objs { let (mut cmd, program) = self.create_compile_object_cmd(obj)?; let token = tokens.acquire().await?; let mut child = spawn(&mut cmd, &program, &self.cargo_output)?; let mut stderr_forwarder = StderrForwarder::new(&mut child); stderr_forwarder.set_non_blocking()?; cell_update(&pendings, |mut pendings| { pendings.push((cmd, program, KillOnDrop(child, stderr_forwarder), token)); pendings }); has_made_progress.set(true); } is_disconnected.set(true); Ok::<_, Error>(()) }; return block_on(wait_future, spawn_future, &has_made_progress); struct KillOnDrop(Child, StderrForwarder); impl Drop for KillOnDrop { fn drop(&mut self) { let child = &mut self.0; child.kill().ok(); } } fn cell_update(cell: &Cell, f: F) where T: Default, F: FnOnce(T) -> T, { let old = cell.take(); let new = f(old); cell.set(new); } } #[cfg(not(feature = "parallel"))] fn compile_objects(&self, objs: &[Object]) -> Result<(), Error> { check_disabled()?; for obj in objs { let (mut cmd, name) = self.create_compile_object_cmd(obj)?; run(&mut cmd, &name, &self.cargo_output)?; } Ok(()) } fn create_compile_object_cmd( &self, obj: &Object, ) -> Result<(Command, Cow<'static, Path>), Error> { let asm_ext = AsmFileExt::from_path(&obj.src); let is_asm = asm_ext.is_some(); let target = self.get_target()?; let msvc = target.env == "msvc"; let compiler = self.try_get_compiler()?; let clang = compiler.is_like_clang(); let gnu = compiler.family == ToolFamily::Gnu; let is_assembler_msvc = msvc && asm_ext == Some(AsmFileExt::DotAsm); let (mut cmd, name) = if is_assembler_msvc { let (cmd, name) = self.msvc_macro_assembler()?; (cmd, Cow::Borrowed(Path::new(name))) } else { let mut cmd = compiler.to_command(); for (a, b) in self.env.iter() { cmd.env(a, b); } ( cmd, compiler .path .file_name() .ok_or_else(|| Error::new(ErrorKind::IOError, "Failed to get compiler path.")) .map(PathBuf::from) .map(Cow::Owned)?, ) }; let is_arm = matches!(target.arch, "aarch64" | "arm"); command_add_output_file( &mut cmd, &obj.dst, CmdAddOutputFileArgs { cuda: self.cuda, is_assembler_msvc, msvc: compiler.is_like_msvc(), clang, gnu, is_asm, is_arm, }, ); // armasm and armasm64 don't requrie -c option if !is_assembler_msvc || !is_arm { cmd.arg("-c"); } if self.cuda && self.cuda_file_count() > 1 { cmd.arg("--device-c"); } if is_asm { cmd.args(self.asm_flags.iter().map(std::ops::Deref::deref)); } if compiler.supports_path_delimiter() && !is_assembler_msvc { // #513: For `clang-cl`, separate flags/options from the input file. // When cross-compiling macOS -> Windows, this avoids interpreting // common `/Users/...` paths as the `/U` flag and triggering // `-Wslash-u-filename` warning. cmd.arg("--"); } cmd.arg(&obj.src); if cfg!(target_os = "macos") { self.fix_env_for_apple_os(&mut cmd)?; } Ok((cmd, name)) } /// This will return a result instead of panicking; see [`Self::expand()`] for /// the complete description. pub fn try_expand(&self) -> Result, Error> { let compiler = self.try_get_compiler()?; let mut cmd = compiler.to_command(); for (a, b) in self.env.iter() { cmd.env(a, b); } cmd.arg("-E"); assert!( self.files.len() <= 1, "Expand may only be called for a single file" ); let is_asm = self .files .iter() .map(std::ops::Deref::deref) .find_map(AsmFileExt::from_path) .is_some(); if compiler.family == (ToolFamily::Msvc { clang_cl: true }) && !is_asm { // #513: For `clang-cl`, separate flags/options from the input file. // When cross-compiling macOS -> Windows, this avoids interpreting // common `/Users/...` paths as the `/U` flag and triggering // `-Wslash-u-filename` warning. cmd.arg("--"); } cmd.args(self.files.iter().map(std::ops::Deref::deref)); let name = compiler .path .file_name() .ok_or_else(|| Error::new(ErrorKind::IOError, "Failed to get compiler path."))?; run_output(&mut cmd, name, &self.cargo_output) } /// Run the compiler, returning the macro-expanded version of the input files. /// /// This is only relevant for C and C++ files. /// /// # Panics /// Panics if more than one file is present in the config, or if compiler /// path has an invalid file name. /// /// # Example /// ```no_run /// let out = cc::Build::new().file("src/foo.c").expand(); /// ``` pub fn expand(&self) -> Vec { match self.try_expand() { Err(e) => fail(&e.message), Ok(v) => v, } } /// Get the compiler that's in use for this configuration. /// /// This function will return a `Tool` which represents the culmination /// of this configuration at a snapshot in time. The returned compiler can /// be inspected (e.g. the path, arguments, environment) to forward along to /// other tools, or the `to_command` method can be used to invoke the /// compiler itself. /// /// This method will take into account all configuration such as debug /// information, optimization level, include directories, defines, etc. /// Additionally, the compiler binary in use follows the standard /// conventions for this path, e.g. looking at the explicitly set compiler, /// environment variables (a number of which are inspected here), and then /// falling back to the default configuration. /// /// # Panics /// /// Panics if an error occurred while determining the architecture. pub fn get_compiler(&self) -> Tool { match self.try_get_compiler() { Ok(tool) => tool, Err(e) => fail(&e.message), } } /// Get the compiler that's in use for this configuration. /// /// This will return a result instead of panicking; see /// [`get_compiler()`](Self::get_compiler) for the complete description. pub fn try_get_compiler(&self) -> Result { let opt_level = self.get_opt_level()?; let target = self.get_target()?; let mut cmd = self.get_base_compiler()?; // Disable default flag generation via `no_default_flags` or environment variable let no_defaults = self.no_default_flags || self.getenv_boolean("CRATE_CC_NO_DEFAULTS"); if !no_defaults { self.add_default_flags(&mut cmd, &target, &opt_level)?; } if let Some(ref std) = self.std { let separator = match cmd.family { ToolFamily::Msvc { .. } => ':', ToolFamily::Gnu | ToolFamily::Clang { .. } => '=', }; cmd.push_cc_arg(format!("-std{}{}", separator, std).into()); } for directory in self.include_directories.iter() { cmd.args.push("-I".into()); cmd.args.push(directory.as_os_str().into()); } if let Ok(flags) = self.envflags(if self.cpp { "CXXFLAGS" } else { "CFLAGS" }) { for arg in flags { cmd.push_cc_arg(arg.into()); } } // If warnings and/or extra_warnings haven't been explicitly set, // then we set them only if the environment doesn't already have // CFLAGS/CXXFLAGS, since those variables presumably already contain // the desired set of warnings flags. if self.warnings.unwrap_or(!self.has_flags()) { let wflags = cmd.family.warnings_flags().into(); cmd.push_cc_arg(wflags); } if self.extra_warnings.unwrap_or(!self.has_flags()) { if let Some(wflags) = cmd.family.extra_warnings_flags() { cmd.push_cc_arg(wflags.into()); } } for flag in self.flags.iter() { cmd.args.push((**flag).into()); } // Add cc flags inherited from matching rustc flags if self.inherit_rustflags { self.add_inherited_rustflags(&mut cmd, &target)?; } for flag in self.flags_supported.iter() { if self .is_flag_supported_inner(flag, &cmd, &target) .unwrap_or(false) { cmd.push_cc_arg((**flag).into()); } } for (key, value) in self.definitions.iter() { if let Some(ref value) = *value { cmd.args.push(format!("-D{}={}", key, value).into()); } else { cmd.args.push(format!("-D{}", key).into()); } } if self.warnings_into_errors { let warnings_to_errors_flag = cmd.family.warnings_to_errors_flag().into(); cmd.push_cc_arg(warnings_to_errors_flag); } // Copied from // // Disables non-English messages from localized linkers. // Such messages may cause issues with text encoding on Windows // and prevent inspection of msvc output in case of errors, which we occasionally do. // This should be acceptable because other messages from rustc are in English anyway, // and may also be desirable to improve searchability of the compiler diagnostics. if matches!(cmd.family, ToolFamily::Msvc { clang_cl: false }) { cmd.env.push(("VSLANG".into(), "1033".into())); } else { cmd.env.push(("LC_ALL".into(), "C".into())); } Ok(cmd) } fn add_default_flags( &self, cmd: &mut Tool, target: &TargetInfo<'_>, opt_level: &str, ) -> Result<(), Error> { let raw_target = self.get_raw_target()?; // Non-target flags // If the flag is not conditioned on target variable, it belongs here :) match cmd.family { ToolFamily::Msvc { .. } => { cmd.push_cc_arg("-nologo".into()); let crt_flag = match self.static_crt { Some(true) => "-MT", Some(false) => "-MD", None => { let features = self.getenv("CARGO_CFG_TARGET_FEATURE"); let features = features.as_deref().unwrap_or_default(); if features.to_string_lossy().contains("crt-static") { "-MT" } else { "-MD" } } }; cmd.push_cc_arg(crt_flag.into()); match opt_level { // Msvc uses /O1 to enable all optimizations that minimize code size. "z" | "s" | "1" => cmd.push_opt_unless_duplicate("-O1".into()), // -O3 is a valid value for gcc and clang compilers, but not msvc. Cap to /O2. "2" | "3" => cmd.push_opt_unless_duplicate("-O2".into()), _ => {} } } ToolFamily::Gnu | ToolFamily::Clang { .. } => { // arm-linux-androideabi-gcc 4.8 shipped with Android NDK does // not support '-Oz' if opt_level == "z" && !cmd.is_like_clang() { cmd.push_opt_unless_duplicate("-Os".into()); } else { cmd.push_opt_unless_duplicate(format!("-O{}", opt_level).into()); } if cmd.is_like_clang() && target.os == "android" { // For compatibility with code that doesn't use pre-defined `__ANDROID__` macro. // If compiler used via ndk-build or cmake (officially supported build methods) // this macros is defined. // See https://android.googlesource.com/platform/ndk/+/refs/heads/ndk-release-r21/build/cmake/android.toolchain.cmake#456 // https://android.googlesource.com/platform/ndk/+/refs/heads/ndk-release-r21/build/core/build-binary.mk#141 cmd.push_opt_unless_duplicate("-DANDROID".into()); } if target.os != "ios" && target.os != "watchos" && target.os != "tvos" && target.os != "visionos" { cmd.push_cc_arg("-ffunction-sections".into()); cmd.push_cc_arg("-fdata-sections".into()); } // Disable generation of PIC on bare-metal for now: rust-lld doesn't support this yet // // `rustc` also defaults to disable PIC on WASM: // if self.pic.unwrap_or( target.os != "windows" && target.os != "none" && target.os != "uefi" && target.arch != "wasm32" && target.arch != "wasm64", ) { cmd.push_cc_arg("-fPIC".into()); // PLT only applies if code is compiled with PIC support, // and only for ELF targets. if (target.os == "linux" || target.os == "android") && !self.use_plt.unwrap_or(true) { cmd.push_cc_arg("-fno-plt".into()); } } if target.arch == "wasm32" || target.arch == "wasm64" { // WASI does not support exceptions yet. // https://github.com/WebAssembly/exception-handling // // `rustc` also defaults to (currently) disable exceptions // on all WASM targets: // cmd.push_cc_arg("-fno-exceptions".into()); } if target.os == "wasi" { // Link clang sysroot if let Ok(wasi_sysroot) = self.wasi_sysroot() { cmd.push_cc_arg( format!("--sysroot={}", Path::new(&wasi_sysroot).display()).into(), ); } // FIXME(madsmtm): Read from `target_features` instead? if raw_target.contains("threads") { cmd.push_cc_arg("-pthread".into()); } } if target.os == "nto" { // Select the target with `-V`, see qcc documentation: // QNX 7.1: https://www.qnx.com/developers/docs/7.1/index.html#com.qnx.doc.neutrino.utilities/topic/q/qcc.html // QNX 8.0: https://www.qnx.com/developers/docs/8.0/com.qnx.doc.neutrino.utilities/topic/q/qcc.html // This assumes qcc/q++ as compiler, which is currently the only supported compiler for QNX. // See for details: https://github.com/rust-lang/cc-rs/pull/1319 let arg = match target.arch { "i586" => "-Vgcc_ntox86_cxx", "aarch64" => "-Vgcc_ntoaarch64le_cxx", "x86_64" => "-Vgcc_ntox86_64_cxx", _ => { return Err(Error::new( ErrorKind::InvalidTarget, format!("Unknown architecture for Neutrino QNX: {}", target.arch), )) } }; cmd.push_cc_arg(arg.into()); } } } if self.get_debug() { if self.cuda { // NVCC debug flag cmd.args.push("-G".into()); } let family = cmd.family; family.add_debug_flags(cmd, self.get_dwarf_version()); } if self.get_force_frame_pointer() { let family = cmd.family; family.add_force_frame_pointer(cmd); } if !cmd.is_like_msvc() { if target.arch == "x86" { cmd.args.push("-m32".into()); } else if target.abi == "x32" { cmd.args.push("-mx32".into()); } else if target.os == "aix" { if cmd.family == ToolFamily::Gnu { cmd.args.push("-maix64".into()); } else { cmd.args.push("-m64".into()); } } else if target.arch == "x86_64" || target.arch == "powerpc64" { cmd.args.push("-m64".into()); } } // Target flags match cmd.family { ToolFamily::Clang { .. } => { if !(cmd.has_internal_target_arg || (target.os == "android" && android_clang_compiler_uses_target_arg_internally(&cmd.path))) { if target.os == "freebsd" { // FreeBSD only supports C++11 and above when compiling against libc++ // (available from FreeBSD 10 onwards). Under FreeBSD, clang uses libc++ by // default on FreeBSD 10 and newer unless `--target` is manually passed to // the compiler, in which case its default behavior differs: // * If --target=xxx-unknown-freebsdX(.Y) is specified and X is greater than // or equal to 10, clang++ uses libc++ // * If --target=xxx-unknown-freebsd is specified (without a version), // clang++ cannot assume libc++ is available and reverts to a default of // libstdc++ (this behavior was changed in llvm 14). // // This breaks C++11 (or greater) builds if targeting FreeBSD with the // generic xxx-unknown-freebsd triple on clang 13 or below *without* // explicitly specifying that libc++ should be used. // When cross-compiling, we can't infer from the rust/cargo target triple // which major version of FreeBSD we are targeting, so we need to make sure // that libc++ is used (unless the user has explicitly specified otherwise). // There's no compelling reason to use a different approach when compiling // natively. if self.cpp && self.cpp_set_stdlib.is_none() { cmd.push_cc_arg("-stdlib=libc++".into()); } } // Add version information to the target. let llvm_target = if target.vendor == "apple" { let deployment_target = self.apple_deployment_target(target); target.versioned_llvm_target(Some(&deployment_target)) } else { target.versioned_llvm_target(None) }; // Pass `--target` with the LLVM target to properly // configure Clang even when cross-compiling. cmd.push_cc_arg(format!("--target={llvm_target}").into()); } } ToolFamily::Msvc { clang_cl } => { // This is an undocumented flag from MSVC but helps with making // builds more reproducible by avoiding putting timestamps into // files. cmd.push_cc_arg("-Brepro".into()); if clang_cl { if target.arch == "x86_64" { cmd.push_cc_arg("-m64".into()); } else if target.arch == "x86" { cmd.push_cc_arg("-m32".into()); cmd.push_cc_arg("-arch:IA32".into()); } else { let llvm_target = target.versioned_llvm_target(None); cmd.push_cc_arg(format!("--target={llvm_target}").into()); } } else if target.full_arch == "i586" { cmd.push_cc_arg("-arch:IA32".into()); } else if target.full_arch == "arm64ec" { cmd.push_cc_arg("-arm64EC".into()); } // There is a check in corecrt.h that will generate a // compilation error if // _ARM_WINAPI_PARTITION_DESKTOP_SDK_AVAILABLE is // not defined to 1. The check was added in Windows // 8 days because only store apps were allowed on ARM. // This changed with the release of Windows 10 IoT Core. // The check will be going away in future versions of // the SDK, but for all released versions of the // Windows SDK it is required. if target.arch == "arm" { cmd.args .push("-D_ARM_WINAPI_PARTITION_DESKTOP_SDK_AVAILABLE=1".into()); } } ToolFamily::Gnu => { if target.vendor == "apple" { let arch = map_darwin_target_from_rust_to_compiler_architecture(target); cmd.args.push("-arch".into()); cmd.args.push(arch.into()); } if target.vendor == "kmc" { cmd.args.push("-finput-charset=utf-8".into()); } if self.static_flag.is_none() { let features = self.getenv("CARGO_CFG_TARGET_FEATURE"); let features = features.as_deref().unwrap_or_default(); if features.to_string_lossy().contains("crt-static") { cmd.args.push("-static".into()); } } // armv7 targets get to use armv7 instructions if (target.full_arch.starts_with("armv7") || target.full_arch.starts_with("thumbv7")) && (target.os == "linux" || target.vendor == "kmc") { cmd.args.push("-march=armv7-a".into()); if target.abi == "eabihf" { // lowest common denominator FPU cmd.args.push("-mfpu=vfpv3-d16".into()); cmd.args.push("-mfloat-abi=hard".into()); } } // (x86 Android doesn't say "eabi") if target.os == "android" && target.full_arch.contains("v7") { cmd.args.push("-march=armv7-a".into()); cmd.args.push("-mthumb".into()); if !target.full_arch.contains("neon") { // On android we can guarantee some extra float instructions // (specified in the android spec online) // NEON guarantees even more; see below. cmd.args.push("-mfpu=vfpv3-d16".into()); } cmd.args.push("-mfloat-abi=softfp".into()); } if target.full_arch.contains("neon") { cmd.args.push("-mfpu=neon-vfpv4".into()); } if target.full_arch == "armv4t" && target.os == "linux" { cmd.args.push("-march=armv4t".into()); cmd.args.push("-marm".into()); cmd.args.push("-mfloat-abi=soft".into()); } if target.full_arch == "armv5te" && target.os == "linux" { cmd.args.push("-march=armv5te".into()); cmd.args.push("-marm".into()); cmd.args.push("-mfloat-abi=soft".into()); } // For us arm == armv6 by default if target.full_arch == "arm" && target.os == "linux" { cmd.args.push("-march=armv6".into()); cmd.args.push("-marm".into()); if target.abi == "eabihf" { cmd.args.push("-mfpu=vfp".into()); } else { cmd.args.push("-mfloat-abi=soft".into()); } } // Turn codegen down on i586 to avoid some instructions. if target.full_arch == "i586" && target.os == "linux" { cmd.args.push("-march=pentium".into()); } // Set codegen level for i686 correctly if target.full_arch == "i686" && target.os == "linux" { cmd.args.push("-march=i686".into()); } // Looks like `musl-gcc` makes it hard for `-m32` to make its way // all the way to the linker, so we need to actually instruct the // linker that we're generating 32-bit executables as well. This'll // typically only be used for build scripts which transitively use // these flags that try to compile executables. if target.arch == "x86" && target.env == "musl" { cmd.args.push("-Wl,-melf_i386".into()); } if target.arch == "arm" && target.os == "none" && target.abi == "eabihf" { cmd.args.push("-mfloat-abi=hard".into()) } if target.full_arch.starts_with("thumb") { cmd.args.push("-mthumb".into()); } if target.full_arch.starts_with("thumbv6m") { cmd.args.push("-march=armv6s-m".into()); } if target.full_arch.starts_with("thumbv7em") { cmd.args.push("-march=armv7e-m".into()); if target.abi == "eabihf" { cmd.args.push("-mfpu=fpv4-sp-d16".into()) } } if target.full_arch.starts_with("thumbv7m") { cmd.args.push("-march=armv7-m".into()); } if target.full_arch.starts_with("thumbv8m.base") { cmd.args.push("-march=armv8-m.base".into()); } if target.full_arch.starts_with("thumbv8m.main") { cmd.args.push("-march=armv8-m.main".into()); if target.abi == "eabihf" { cmd.args.push("-mfpu=fpv5-sp-d16".into()) } } if target.full_arch.starts_with("armebv7r") | target.full_arch.starts_with("armv7r") { if target.full_arch.starts_with("armeb") { cmd.args.push("-mbig-endian".into()); } else { cmd.args.push("-mlittle-endian".into()); } // ARM mode cmd.args.push("-marm".into()); // R Profile cmd.args.push("-march=armv7-r".into()); if target.abi == "eabihf" { // lowest common denominator FPU // (see Cortex-R4 technical reference manual) cmd.args.push("-mfpu=vfpv3-d16".into()) } } if target.full_arch.starts_with("armv7a") { cmd.args.push("-march=armv7-a".into()); if target.abi == "eabihf" { // lowest common denominator FPU cmd.args.push("-mfpu=vfpv3-d16".into()); } } if target.arch == "riscv32" || target.arch == "riscv64" { // get the 32i/32imac/32imc/64gc/64imac/... part let arch = &target.full_arch[5..]; if arch.starts_with("64") { if matches!(target.os, "linux" | "freebsd" | "netbsd") { cmd.args.push(("-march=rv64gc").into()); cmd.args.push("-mabi=lp64d".into()); } else { cmd.args.push(("-march=rv".to_owned() + arch).into()); cmd.args.push("-mabi=lp64".into()); } } else if arch.starts_with("32") { if target.os == "linux" { cmd.args.push(("-march=rv32gc").into()); cmd.args.push("-mabi=ilp32d".into()); } else { cmd.args.push(("-march=rv".to_owned() + arch).into()); cmd.args.push("-mabi=ilp32".into()); } } else { cmd.args.push("-mcmodel=medany".into()); } } } } if target.vendor == "apple" { self.apple_flags(cmd)?; } if self.static_flag.unwrap_or(false) { cmd.args.push("-static".into()); } if self.shared_flag.unwrap_or(false) { cmd.args.push("-shared".into()); } if self.cpp { match (self.cpp_set_stdlib.as_ref(), cmd.family) { (None, _) => {} (Some(stdlib), ToolFamily::Gnu) | (Some(stdlib), ToolFamily::Clang { .. }) => { cmd.push_cc_arg(format!("-stdlib=lib{}", stdlib).into()); } _ => { self.cargo_output.print_warning(&format_args!("cpp_set_stdlib is specified, but the {:?} compiler does not support this option, ignored", cmd.family)); } } } Ok(()) } fn add_inherited_rustflags( &self, cmd: &mut Tool, target: &TargetInfo<'_>, ) -> Result<(), Error> { let env_os = match self.getenv("CARGO_ENCODED_RUSTFLAGS") { Some(env) => env, // No encoded RUSTFLAGS -> nothing to do None => return Ok(()), }; let env = env_os.to_string_lossy(); let codegen_flags = RustcCodegenFlags::parse(&env)?; codegen_flags.cc_flags(self, cmd, target); Ok(()) } fn has_flags(&self) -> bool { let flags_env_var_name = if self.cpp { "CXXFLAGS" } else { "CFLAGS" }; let flags_env_var_value = self.getenv_with_target_prefixes(flags_env_var_name); flags_env_var_value.is_ok() } fn msvc_macro_assembler(&self) -> Result<(Command, &'static str), Error> { let target = self.get_target()?; let tool = if target.arch == "x86_64" { "ml64.exe" } else if target.arch == "arm" { "armasm.exe" } else if target.arch == "aarch64" { "armasm64.exe" } else { "ml.exe" }; let mut cmd = self .windows_registry_find(&target, tool) .unwrap_or_else(|| self.cmd(tool)); cmd.arg("-nologo"); // undocumented, yet working with armasm[64] for directory in self.include_directories.iter() { cmd.arg("-I").arg(&**directory); } if target.arch == "aarch64" || target.arch == "arm" { if self.get_debug() { cmd.arg("-g"); } for (key, value) in self.definitions.iter() { cmd.arg("-PreDefine"); if let Some(ref value) = *value { if let Ok(i) = value.parse::() { cmd.arg(format!("{} SETA {}", key, i)); } else if value.starts_with('"') && value.ends_with('"') { cmd.arg(format!("{} SETS {}", key, value)); } else { cmd.arg(format!("{} SETS \"{}\"", key, value)); } } else { cmd.arg(format!("{} SETL {}", key, "{TRUE}")); } } } else { if self.get_debug() { cmd.arg("-Zi"); } for (key, value) in self.definitions.iter() { if let Some(ref value) = *value { cmd.arg(format!("-D{}={}", key, value)); } else { cmd.arg(format!("-D{}", key)); } } } if target.arch == "x86" { cmd.arg("-safeseh"); } Ok((cmd, tool)) } fn assemble(&self, lib_name: &str, dst: &Path, objs: &[Object]) -> Result<(), Error> { // Delete the destination if it exists as we want to // create on the first iteration instead of appending. let _ = fs::remove_file(dst); // Add objects to the archive in limited-length batches. This helps keep // the length of the command line within a reasonable length to avoid // blowing system limits on limiting platforms like Windows. let objs: Vec<_> = objs .iter() .map(|o| o.dst.as_path()) .chain(self.objects.iter().map(std::ops::Deref::deref)) .collect(); for chunk in objs.chunks(100) { self.assemble_progressive(dst, chunk)?; } if self.cuda && self.cuda_file_count() > 0 { // Link the device-side code and add it to the target library, // so that non-CUDA linker can link the final binary. let out_dir = self.get_out_dir()?; let dlink = out_dir.join(lib_name.to_owned() + "_dlink.o"); let mut nvcc = self.get_compiler().to_command(); nvcc.arg("--device-link").arg("-o").arg(&dlink).arg(dst); run(&mut nvcc, "nvcc", &self.cargo_output)?; self.assemble_progressive(dst, &[dlink.as_path()])?; } let target = self.get_target()?; if target.env == "msvc" { // The Rust compiler will look for libfoo.a and foo.lib, but the // MSVC linker will also be passed foo.lib, so be sure that both // exist for now. let lib_dst = dst.with_file_name(format!("{}.lib", lib_name)); let _ = fs::remove_file(&lib_dst); match fs::hard_link(dst, &lib_dst).or_else(|_| { // if hard-link fails, just copy (ignoring the number of bytes written) fs::copy(dst, &lib_dst).map(|_| ()) }) { Ok(_) => (), Err(_) => { return Err(Error::new( ErrorKind::IOError, "Could not copy or create a hard-link to the generated lib file.", )); } }; } else { // Non-msvc targets (those using `ar`) need a separate step to add // the symbol table to archives since our construction command of // `cq` doesn't add it for us. let (mut ar, cmd, _any_flags) = self.get_ar()?; // NOTE: We add `s` even if flags were passed using $ARFLAGS/ar_flag, because `s` // here represents a _mode_, not an arbitrary flag. Further discussion of this choice // can be seen in https://github.com/rust-lang/cc-rs/pull/763. run(ar.arg("s").arg(dst), &cmd, &self.cargo_output)?; } Ok(()) } fn assemble_progressive(&self, dst: &Path, objs: &[&Path]) -> Result<(), Error> { let target = self.get_target()?; let (mut cmd, program, any_flags) = self.get_ar()?; if target.env == "msvc" && !program.to_string_lossy().contains("llvm-ar") { // NOTE: -out: here is an I/O flag, and so must be included even if $ARFLAGS/ar_flag is // in use. -nologo on the other hand is just a regular flag, and one that we'll skip if // the caller has explicitly dictated the flags they want. See // https://github.com/rust-lang/cc-rs/pull/763 for further discussion. let mut out = OsString::from("-out:"); out.push(dst); cmd.arg(out); if !any_flags { cmd.arg("-nologo"); } // If the library file already exists, add the library name // as an argument to let lib.exe know we are appending the objs. if dst.exists() { cmd.arg(dst); } cmd.args(objs); run(&mut cmd, &program, &self.cargo_output)?; } else { // Set an environment variable to tell the OSX archiver to ensure // that all dates listed in the archive are zero, improving // determinism of builds. AFAIK there's not really official // documentation of this but there's a lot of references to it if // you search google. // // You can reproduce this locally on a mac with: // // $ touch foo.c // $ cc -c foo.c -o foo.o // // # Notice that these two checksums are different // $ ar crus libfoo1.a foo.o && sleep 2 && ar crus libfoo2.a foo.o // $ md5sum libfoo*.a // // # Notice that these two checksums are the same // $ export ZERO_AR_DATE=1 // $ ar crus libfoo1.a foo.o && sleep 2 && touch foo.o && ar crus libfoo2.a foo.o // $ md5sum libfoo*.a // // In any case if this doesn't end up getting read, it shouldn't // cause that many issues! cmd.env("ZERO_AR_DATE", "1"); // NOTE: We add cq here regardless of whether $ARFLAGS/ar_flag have been used because // it dictates the _mode_ ar runs in, which the setter of $ARFLAGS/ar_flag can't // dictate. See https://github.com/rust-lang/cc-rs/pull/763 for further discussion. run( cmd.arg("cq").arg(dst).args(objs), &program, &self.cargo_output, )?; } Ok(()) } fn apple_flags(&self, cmd: &mut Tool) -> Result<(), Error> { let target = self.get_target()?; // If the compiler is Clang, then we've already specifed the target // information (including the deployment target) with the `--target` // option, so we don't need to do anything further here. // // If the compiler is GCC, then we need to specify // `-mmacosx-version-min` to set the deployment target, as well // as to say that the target OS is macOS. // // NOTE: GCC does not support `-miphoneos-version-min=` etc. (because // it does not support iOS in general), but we specify them anyhow in // case we actually have a Clang-like compiler disguised as a GNU-like // compiler, or in case GCC adds support for these in the future. if !cmd.is_like_clang() { let min_version = self.apple_deployment_target(&target); cmd.args .push(target.apple_version_flag(&min_version).into()); } // AppleClang sometimes requires sysroot even on macOS if cmd.is_xctoolchain_clang() || target.os != "macos" { self.cargo_output.print_metadata(&format_args!( "Detecting {:?} SDK path for {}", target.os, target.apple_sdk_name(), )); let sdk_path = self.apple_sdk_root(&target)?; cmd.args.push("-isysroot".into()); cmd.args.push(OsStr::new(&sdk_path).to_owned()); if target.abi == "macabi" { // Mac Catalyst uses the macOS SDK, but to compile against and // link to iOS-specific frameworks, we should have the support // library stubs in the include and library search path. let ios_support = Path::new(&sdk_path).join("System/iOSSupport"); cmd.args.extend([ // Header search path OsString::from("-isystem"), ios_support.join("usr/include").into(), // Framework header search path OsString::from("-iframework"), ios_support.join("System/Library/Frameworks").into(), // Library search path { let mut s = OsString::from("-L"); s.push(ios_support.join("usr/lib")); s }, // Framework linker search path { // Technically, we _could_ avoid emitting `-F`, as // `-iframework` implies it, but let's keep it in for // clarity. let mut s = OsString::from("-F"); s.push(ios_support.join("System/Library/Frameworks")); s }, ]); } } Ok(()) } fn cmd>(&self, prog: P) -> Command { let mut cmd = Command::new(prog); for (a, b) in self.env.iter() { cmd.env(a, b); } cmd } fn get_base_compiler(&self) -> Result { let out_dir = self.get_out_dir().ok(); let out_dir = out_dir.as_deref(); if let Some(c) = &self.compiler { return Ok(Tool::new( (**c).to_owned(), &self.build_cache.cached_compiler_family, &self.cargo_output, out_dir, )); } let target = self.get_target()?; let raw_target = self.get_raw_target()?; let (env, msvc, gnu, traditional, clang) = if self.cpp { ("CXX", "cl.exe", "g++", "c++", "clang++") } else { ("CC", "cl.exe", "gcc", "cc", "clang") }; // On historical Solaris systems, "cc" may have been Sun Studio, which // is not flag-compatible with "gcc". This history casts a long shadow, // and many modern illumos distributions today ship GCC as "gcc" without // also making it available as "cc". let default = if cfg!(target_os = "solaris") || cfg!(target_os = "illumos") { gnu } else { traditional }; let cl_exe = self.windows_registry_find_tool(&target, "cl.exe"); let tool_opt: Option = self .env_tool(env) .map(|(tool, wrapper, args)| { // find the driver mode, if any const DRIVER_MODE: &str = "--driver-mode="; let driver_mode = args .iter() .find(|a| a.starts_with(DRIVER_MODE)) .map(|a| &a[DRIVER_MODE.len()..]); // Chop off leading/trailing whitespace to work around // semi-buggy build scripts which are shared in // makefiles/configure scripts (where spaces are far more // lenient) let mut t = Tool::with_clang_driver( tool, driver_mode, &self.build_cache.cached_compiler_family, &self.cargo_output, out_dir, ); if let Some(cc_wrapper) = wrapper { t.cc_wrapper_path = Some(Path::new(&cc_wrapper).to_owned()); } for arg in args { t.cc_wrapper_args.push(arg.into()); } t }) .or_else(|| { if target.os == "emscripten" { let tool = if self.cpp { "em++" } else { "emcc" }; // Windows uses bat file so we have to be a bit more specific if cfg!(windows) { let mut t = Tool::with_family( PathBuf::from("cmd"), ToolFamily::Clang { zig_cc: false }, ); t.args.push("/c".into()); t.args.push(format!("{}.bat", tool).into()); Some(t) } else { Some(Tool::new( PathBuf::from(tool), &self.build_cache.cached_compiler_family, &self.cargo_output, out_dir, )) } } else { None } }) .or_else(|| cl_exe.clone()); let tool = match tool_opt { Some(t) => t, None => { let compiler = if cfg!(windows) && target.os == "windows" { if target.env == "msvc" { msvc.to_string() } else { let cc = if target.abi == "llvm" { clang } else { gnu }; format!("{}.exe", cc) } } else if target.os == "ios" || target.os == "watchos" || target.os == "tvos" || target.os == "visionos" { clang.to_string() } else if target.os == "android" { autodetect_android_compiler(&raw_target, gnu, clang) } else if target.os == "cloudabi" { format!( "{}-{}-{}-{}", target.full_arch, target.vendor, target.os, traditional ) } else if target.arch == "wasm32" || target.arch == "wasm64" { // Compiling WASM is not currently supported by GCC, so // let's default to Clang. clang.to_string() } else if target.os == "vxworks" { if self.cpp { "wr-c++".to_string() } else { "wr-cc".to_string() } } else if target.arch == "arm" && target.vendor == "kmc" { format!("arm-kmc-eabi-{}", gnu) } else if target.arch == "aarch64" && target.vendor == "kmc" { format!("aarch64-kmc-elf-{}", gnu) } else if target.os == "nto" { // See for details: https://github.com/rust-lang/cc-rs/pull/1319 if self.cpp { "q++".to_string() } else { "qcc".to_string() } } else if self.get_is_cross_compile()? { let prefix = self.prefix_for_target(&raw_target); match prefix { Some(prefix) => { let cc = if target.abi == "llvm" { clang } else { gnu }; format!("{}-{}", prefix, cc) } None => default.to_string(), } } else { default.to_string() }; let mut t = Tool::new( PathBuf::from(compiler), &self.build_cache.cached_compiler_family, &self.cargo_output, out_dir, ); if let Some(cc_wrapper) = self.rustc_wrapper_fallback() { t.cc_wrapper_path = Some(Path::new(&cc_wrapper).to_owned()); } t } }; let mut tool = if self.cuda { assert!( tool.args.is_empty(), "CUDA compilation currently assumes empty pre-existing args" ); let nvcc = match self.getenv_with_target_prefixes("NVCC") { Err(_) => PathBuf::from("nvcc"), Ok(nvcc) => PathBuf::from(&*nvcc), }; let mut nvcc_tool = Tool::with_features( nvcc, None, self.cuda, &self.build_cache.cached_compiler_family, &self.cargo_output, out_dir, ); if self.ccbin { nvcc_tool .args .push(format!("-ccbin={}", tool.path.display()).into()); } if let Some(cc_wrapper) = self.rustc_wrapper_fallback() { nvcc_tool.cc_wrapper_path = Some(Path::new(&cc_wrapper).to_owned()); } nvcc_tool.family = tool.family; nvcc_tool } else { tool }; // New "standalone" C/C++ cross-compiler executables from recent Android NDK // are just shell scripts that call main clang binary (from Android NDK) with // proper `--target` argument. // // For example, armv7a-linux-androideabi16-clang passes // `--target=armv7a-linux-androideabi16` to clang. // // As the shell script calls the main clang binary, the command line limit length // on Windows is restricted to around 8k characters instead of around 32k characters. // To remove this limit, we call the main clang binary directly and construct the // `--target=` ourselves. if cfg!(windows) && android_clang_compiler_uses_target_arg_internally(&tool.path) { if let Some(path) = tool.path.file_name() { let file_name = path.to_str().unwrap().to_owned(); let (target, clang) = file_name.split_at(file_name.rfind('-').unwrap()); tool.has_internal_target_arg = true; tool.path.set_file_name(clang.trim_start_matches('-')); tool.path.set_extension("exe"); tool.args.push(format!("--target={}", target).into()); // Additionally, shell scripts for target i686-linux-android versions 16 to 24 // pass the `mstackrealign` option so we do that here as well. if target.contains("i686-linux-android") { let (_, version) = target.split_at(target.rfind('d').unwrap() + 1); if let Ok(version) = version.parse::() { if version > 15 && version < 25 { tool.args.push("-mstackrealign".into()); } } } }; } // If we found `cl.exe` in our environment, the tool we're returning is // an MSVC-like tool, *and* no env vars were set then set env vars for // the tool that we're returning. // // Env vars are needed for things like `link.exe` being put into PATH as // well as header include paths sometimes. These paths are automatically // included by default but if the `CC` or `CXX` env vars are set these // won't be used. This'll ensure that when the env vars are used to // configure for invocations like `clang-cl` we still get a "works out // of the box" experience. if let Some(cl_exe) = cl_exe { if tool.family == (ToolFamily::Msvc { clang_cl: true }) && tool.env.is_empty() && target.env == "msvc" { for (k, v) in cl_exe.env.iter() { tool.env.push((k.to_owned(), v.to_owned())); } } } if target.env == "msvc" && tool.family == ToolFamily::Gnu { self.cargo_output .print_warning(&"GNU compiler is not supported for this target"); } Ok(tool) } /// Returns a fallback `cc_compiler_wrapper` by introspecting `RUSTC_WRAPPER` fn rustc_wrapper_fallback(&self) -> Option> { // No explicit CC wrapper was detected, but check if RUSTC_WRAPPER // is defined and is a build accelerator that is compatible with // C/C++ compilers (e.g. sccache) const VALID_WRAPPERS: &[&str] = &["sccache", "cachepot", "buildcache"]; let rustc_wrapper = self.getenv("RUSTC_WRAPPER")?; let wrapper_path = Path::new(&rustc_wrapper); let wrapper_stem = wrapper_path.file_stem()?; if VALID_WRAPPERS.contains(&wrapper_stem.to_str()?) { Some(rustc_wrapper) } else { None } } /// Returns compiler path, optional modifier name from whitelist, and arguments vec fn env_tool(&self, name: &str) -> Option<(PathBuf, Option>, Vec)> { let tool = self.getenv_with_target_prefixes(name).ok()?; let tool = tool.to_string_lossy(); let tool = tool.trim(); if tool.is_empty() { return None; } // If this is an exact path on the filesystem we don't want to do any // interpretation at all, just pass it on through. This'll hopefully get // us to support spaces-in-paths. if Path::new(tool).exists() { return Some(( PathBuf::from(tool), self.rustc_wrapper_fallback(), Vec::new(), )); } // Ok now we want to handle a couple of scenarios. We'll assume from // here on out that spaces are splitting separate arguments. Two major // features we want to support are: // // CC='sccache cc' // // aka using `sccache` or any other wrapper/caching-like-thing for // compilations. We want to know what the actual compiler is still, // though, because our `Tool` API support introspection of it to see // what compiler is in use. // // additionally we want to support // // CC='cc -flag' // // where the CC env var is used to also pass default flags to the C // compiler. // // It's true that everything here is a bit of a pain, but apparently if // you're not literally make or bash then you get a lot of bug reports. let mut known_wrappers = vec![ "ccache", "distcc", "sccache", "icecc", "cachepot", "buildcache", ]; let custom_wrapper = self.getenv("CC_KNOWN_WRAPPER_CUSTOM"); if custom_wrapper.is_some() { known_wrappers.push(custom_wrapper.as_deref().unwrap().to_str().unwrap()); } let mut parts = tool.split_whitespace(); let maybe_wrapper = parts.next()?; let file_stem = Path::new(maybe_wrapper).file_stem()?.to_str()?; if known_wrappers.contains(&file_stem) { if let Some(compiler) = parts.next() { return Some(( compiler.into(), Some(Arc::::from(OsStr::new(&maybe_wrapper))), parts.map(|s| s.to_string()).collect(), )); } } Some(( maybe_wrapper.into(), self.rustc_wrapper_fallback(), parts.map(|s| s.to_string()).collect(), )) } /// Returns the C++ standard library: /// 1. If [`cpp_link_stdlib`](cc::Build::cpp_link_stdlib) is set, uses its value. /// 2. Else if the `CXXSTDLIB` environment variable is set, uses its value. /// 3. Else the default is `c++` for OS X and BSDs, `c++_shared` for Android, /// `None` for MSVC and `stdc++` for anything else. fn get_cpp_link_stdlib(&self) -> Result>, Error> { match &self.cpp_link_stdlib { Some(s) => Ok(s.as_deref().map(Path::new).map(Cow::Borrowed)), None => { if let Ok(stdlib) = self.getenv_with_target_prefixes("CXXSTDLIB") { if stdlib.is_empty() { Ok(None) } else { Ok(Some(Cow::Owned(Path::new(&stdlib).to_owned()))) } } else { let target = self.get_target()?; if target.env == "msvc" { Ok(None) } else if target.vendor == "apple" || target.os == "freebsd" || target.os == "openbsd" || target.os == "aix" || (target.os == "linux" && target.env == "ohos") || target.os == "wasi" { Ok(Some(Cow::Borrowed(Path::new("c++")))) } else if target.os == "android" { Ok(Some(Cow::Borrowed(Path::new("c++_shared")))) } else { Ok(Some(Cow::Borrowed(Path::new("stdc++")))) } } } } } fn get_ar(&self) -> Result<(Command, PathBuf, bool), Error> { self.try_get_archiver_and_flags() } /// Get the archiver (ar) that's in use for this configuration. /// /// You can use [`Command::get_program`] to get just the path to the command. /// /// This method will take into account all configuration such as debug /// information, optimization level, include directories, defines, etc. /// Additionally, the compiler binary in use follows the standard /// conventions for this path, e.g. looking at the explicitly set compiler, /// environment variables (a number of which are inspected here), and then /// falling back to the default configuration. /// /// # Panics /// /// Panics if an error occurred while determining the architecture. pub fn get_archiver(&self) -> Command { match self.try_get_archiver() { Ok(tool) => tool, Err(e) => fail(&e.message), } } /// Get the archiver that's in use for this configuration. /// /// This will return a result instead of panicking; /// see [`Self::get_archiver`] for the complete description. pub fn try_get_archiver(&self) -> Result { Ok(self.try_get_archiver_and_flags()?.0) } fn try_get_archiver_and_flags(&self) -> Result<(Command, PathBuf, bool), Error> { let (mut cmd, name) = self.get_base_archiver()?; let mut any_flags = false; if let Ok(flags) = self.envflags("ARFLAGS") { any_flags |= !flags.is_empty(); cmd.args(flags); } for flag in &self.ar_flags { any_flags = true; cmd.arg(&**flag); } Ok((cmd, name, any_flags)) } fn get_base_archiver(&self) -> Result<(Command, PathBuf), Error> { if let Some(ref a) = self.archiver { let archiver = &**a; return Ok((self.cmd(archiver), archiver.into())); } self.get_base_archiver_variant("AR", "ar") } /// Get the ranlib that's in use for this configuration. /// /// You can use [`Command::get_program`] to get just the path to the command. /// /// This method will take into account all configuration such as debug /// information, optimization level, include directories, defines, etc. /// Additionally, the compiler binary in use follows the standard /// conventions for this path, e.g. looking at the explicitly set compiler, /// environment variables (a number of which are inspected here), and then /// falling back to the default configuration. /// /// # Panics /// /// Panics if an error occurred while determining the architecture. pub fn get_ranlib(&self) -> Command { match self.try_get_ranlib() { Ok(tool) => tool, Err(e) => fail(&e.message), } } /// Get the ranlib that's in use for this configuration. /// /// This will return a result instead of panicking; /// see [`Self::get_ranlib`] for the complete description. pub fn try_get_ranlib(&self) -> Result { let mut cmd = self.get_base_ranlib()?; if let Ok(flags) = self.envflags("RANLIBFLAGS") { cmd.args(flags); } Ok(cmd) } fn get_base_ranlib(&self) -> Result { if let Some(ref r) = self.ranlib { return Ok(self.cmd(&**r)); } Ok(self.get_base_archiver_variant("RANLIB", "ranlib")?.0) } fn get_base_archiver_variant( &self, env: &str, tool: &str, ) -> Result<(Command, PathBuf), Error> { let target = self.get_target()?; let mut name = PathBuf::new(); let tool_opt: Option = self .env_tool(env) .map(|(tool, _wrapper, args)| { name.clone_from(&tool); let mut cmd = self.cmd(tool); cmd.args(args); cmd }) .or_else(|| { if target.os == "emscripten" { // Windows use bat files so we have to be a bit more specific if cfg!(windows) { let mut cmd = self.cmd("cmd"); name = format!("em{}.bat", tool).into(); cmd.arg("/c").arg(&name); Some(cmd) } else { name = format!("em{}", tool).into(); Some(self.cmd(&name)) } } else if target.arch == "wasm32" || target.arch == "wasm64" { // Formally speaking one should be able to use this approach, // parsing -print-search-dirs output, to cover all clang targets, // including Android SDKs and other cross-compilation scenarios... // And even extend it to gcc targets by searching for "ar" instead // of "llvm-ar"... let compiler = self.get_base_compiler().ok()?; if compiler.is_like_clang() { name = format!("llvm-{}", tool).into(); self.search_programs( &mut self.cmd(&compiler.path), &name, &self.cargo_output, ) .map(|name| self.cmd(name)) } else { None } } else { None } }); let default = tool.to_string(); let tool = match tool_opt { Some(t) => t, None => { if target.os == "android" { name = format!("llvm-{}", tool).into(); match Command::new(&name).arg("--version").status() { Ok(status) if status.success() => (), _ => { // FIXME: Use parsed target. let raw_target = self.get_raw_target()?; name = format!("{}-{}", raw_target.replace("armv7", "arm"), tool).into() } } self.cmd(&name) } else if target.env == "msvc" { // NOTE: There isn't really a ranlib on msvc, so arguably we should return // `None` somehow here. But in general, callers will already have to be aware // of not running ranlib on Windows anyway, so it feels okay to return lib.exe // here. let compiler = self.get_base_compiler()?; let mut lib = String::new(); if compiler.family == (ToolFamily::Msvc { clang_cl: true }) { // See if there is 'llvm-lib' next to 'clang-cl' // Another possibility could be to see if there is 'clang' // next to 'clang-cl' and use 'search_programs()' to locate // 'llvm-lib'. This is because 'clang-cl' doesn't support // the -print-search-dirs option. if let Some(mut cmd) = self.which(&compiler.path, None) { cmd.pop(); cmd.push("llvm-lib.exe"); if let Some(llvm_lib) = self.which(&cmd, None) { llvm_lib.to_str().unwrap().clone_into(&mut lib); } } } if lib.is_empty() { name = PathBuf::from("lib.exe"); let mut cmd = match self.windows_registry_find(&target, "lib.exe") { Some(t) => t, None => self.cmd("lib.exe"), }; if target.full_arch == "arm64ec" { cmd.arg("/machine:arm64ec"); } cmd } else { name = lib.into(); self.cmd(&name) } } else if target.os == "illumos" { // The default 'ar' on illumos uses a non-standard flags, // but the OS comes bundled with a GNU-compatible variant. // // Use the GNU-variant to match other Unix systems. name = format!("g{}", tool).into(); self.cmd(&name) } else if self.get_is_cross_compile()? { match self.prefix_for_target(&self.get_raw_target()?) { Some(p) => { // GCC uses $target-gcc-ar, whereas binutils uses $target-ar -- try both. // Prefer -ar if it exists, as builds of `-gcc-ar` have been observed to be // outright broken (such as when targeting freebsd with `--disable-lto` // toolchain where the archiver attempts to load the LTO plugin anyway but // fails to find one). // // The same applies to ranlib. let mut chosen = default; for &infix in &["", "-gcc"] { let target_p = format!("{}{}-{}", p, infix, tool); if Command::new(&target_p).output().is_ok() { chosen = target_p; break; } } name = chosen.into(); self.cmd(&name) } None => { name = default.into(); self.cmd(&name) } } } else { name = default.into(); self.cmd(&name) } } }; Ok((tool, name)) } // FIXME: Use parsed target instead of raw target. fn prefix_for_target(&self, target: &str) -> Option> { // CROSS_COMPILE is of the form: "arm-linux-gnueabi-" self.getenv("CROSS_COMPILE") .as_deref() .map(|s| s.to_string_lossy().trim_end_matches('-').to_owned()) .map(Cow::Owned) .or_else(|| { // Put aside RUSTC_LINKER's prefix to be used as second choice, after CROSS_COMPILE self.getenv("RUSTC_LINKER").and_then(|var| { var.to_string_lossy() .strip_suffix("-gcc") .map(str::to_string) .map(Cow::Owned) }) }) .or_else(|| { match target { // Note: there is no `aarch64-pc-windows-gnu` target, only `-gnullvm` "aarch64-pc-windows-gnullvm" => Some("aarch64-w64-mingw32"), "aarch64-uwp-windows-gnu" => Some("aarch64-w64-mingw32"), "aarch64-unknown-linux-gnu" => Some("aarch64-linux-gnu"), "aarch64-unknown-linux-musl" => Some("aarch64-linux-musl"), "aarch64-unknown-netbsd" => Some("aarch64--netbsd"), "arm-unknown-linux-gnueabi" => Some("arm-linux-gnueabi"), "armv4t-unknown-linux-gnueabi" => Some("arm-linux-gnueabi"), "armv5te-unknown-linux-gnueabi" => Some("arm-linux-gnueabi"), "armv5te-unknown-linux-musleabi" => Some("arm-linux-gnueabi"), "arm-unknown-linux-gnueabihf" => Some("arm-linux-gnueabihf"), "arm-unknown-linux-musleabi" => Some("arm-linux-musleabi"), "arm-unknown-linux-musleabihf" => Some("arm-linux-musleabihf"), "arm-unknown-netbsd-eabi" => Some("arm--netbsdelf-eabi"), "armv6-unknown-netbsd-eabihf" => Some("armv6--netbsdelf-eabihf"), "armv7-unknown-linux-gnueabi" => Some("arm-linux-gnueabi"), "armv7-unknown-linux-gnueabihf" => Some("arm-linux-gnueabihf"), "armv7-unknown-linux-musleabihf" => Some("arm-linux-musleabihf"), "armv7neon-unknown-linux-gnueabihf" => Some("arm-linux-gnueabihf"), "armv7neon-unknown-linux-musleabihf" => Some("arm-linux-musleabihf"), "thumbv7-unknown-linux-gnueabihf" => Some("arm-linux-gnueabihf"), "thumbv7-unknown-linux-musleabihf" => Some("arm-linux-musleabihf"), "thumbv7neon-unknown-linux-gnueabihf" => Some("arm-linux-gnueabihf"), "thumbv7neon-unknown-linux-musleabihf" => Some("arm-linux-musleabihf"), "armv7-unknown-netbsd-eabihf" => Some("armv7--netbsdelf-eabihf"), "hexagon-unknown-linux-musl" => Some("hexagon-linux-musl"), "i586-unknown-linux-musl" => Some("musl"), "i686-pc-windows-gnu" => Some("i686-w64-mingw32"), "i686-pc-windows-gnullvm" => Some("i686-w64-mingw32"), "i686-uwp-windows-gnu" => Some("i686-w64-mingw32"), "i686-unknown-linux-gnu" => self.find_working_gnu_prefix(&[ "i686-linux-gnu", "x86_64-linux-gnu", // transparently support gcc-multilib ]), // explicit None if not found, so caller knows to fall back "i686-unknown-linux-musl" => Some("musl"), "i686-unknown-netbsd" => Some("i486--netbsdelf"), "loongarch64-unknown-linux-gnu" => Some("loongarch64-linux-gnu"), "mips-unknown-linux-gnu" => Some("mips-linux-gnu"), "mips-unknown-linux-musl" => Some("mips-linux-musl"), "mipsel-unknown-linux-gnu" => Some("mipsel-linux-gnu"), "mipsel-unknown-linux-musl" => Some("mipsel-linux-musl"), "mips64-unknown-linux-gnuabi64" => Some("mips64-linux-gnuabi64"), "mips64el-unknown-linux-gnuabi64" => Some("mips64el-linux-gnuabi64"), "mipsisa32r6-unknown-linux-gnu" => Some("mipsisa32r6-linux-gnu"), "mipsisa32r6el-unknown-linux-gnu" => Some("mipsisa32r6el-linux-gnu"), "mipsisa64r6-unknown-linux-gnuabi64" => Some("mipsisa64r6-linux-gnuabi64"), "mipsisa64r6el-unknown-linux-gnuabi64" => Some("mipsisa64r6el-linux-gnuabi64"), "powerpc-unknown-linux-gnu" => Some("powerpc-linux-gnu"), "powerpc-unknown-linux-gnuspe" => Some("powerpc-linux-gnuspe"), "powerpc-unknown-netbsd" => Some("powerpc--netbsd"), "powerpc64-unknown-linux-gnu" => Some("powerpc-linux-gnu"), "powerpc64le-unknown-linux-gnu" => Some("powerpc64le-linux-gnu"), "riscv32i-unknown-none-elf" => self.find_working_gnu_prefix(&[ "riscv32-unknown-elf", "riscv64-unknown-elf", "riscv-none-embed", ]), "riscv32imac-esp-espidf" => Some("riscv32-esp-elf"), "riscv32imac-unknown-none-elf" => self.find_working_gnu_prefix(&[ "riscv32-unknown-elf", "riscv64-unknown-elf", "riscv-none-embed", ]), "riscv32imac-unknown-xous-elf" => self.find_working_gnu_prefix(&[ "riscv32-unknown-elf", "riscv64-unknown-elf", "riscv-none-embed", ]), "riscv32imc-esp-espidf" => Some("riscv32-esp-elf"), "riscv32imc-unknown-none-elf" => self.find_working_gnu_prefix(&[ "riscv32-unknown-elf", "riscv64-unknown-elf", "riscv-none-embed", ]), "riscv64gc-unknown-none-elf" => self.find_working_gnu_prefix(&[ "riscv64-unknown-elf", "riscv32-unknown-elf", "riscv-none-embed", ]), "riscv64imac-unknown-none-elf" => self.find_working_gnu_prefix(&[ "riscv64-unknown-elf", "riscv32-unknown-elf", "riscv-none-embed", ]), "riscv64gc-unknown-linux-gnu" => Some("riscv64-linux-gnu"), "riscv32gc-unknown-linux-gnu" => Some("riscv32-linux-gnu"), "riscv64gc-unknown-linux-musl" => Some("riscv64-linux-musl"), "riscv32gc-unknown-linux-musl" => Some("riscv32-linux-musl"), "riscv64gc-unknown-netbsd" => Some("riscv64--netbsd"), "s390x-unknown-linux-gnu" => Some("s390x-linux-gnu"), "sparc-unknown-linux-gnu" => Some("sparc-linux-gnu"), "sparc64-unknown-linux-gnu" => Some("sparc64-linux-gnu"), "sparc64-unknown-netbsd" => Some("sparc64--netbsd"), "sparcv9-sun-solaris" => Some("sparcv9-sun-solaris"), "armv7a-none-eabi" => Some("arm-none-eabi"), "armv7a-none-eabihf" => Some("arm-none-eabi"), "armebv7r-none-eabi" => Some("arm-none-eabi"), "armebv7r-none-eabihf" => Some("arm-none-eabi"), "armv7r-none-eabi" => Some("arm-none-eabi"), "armv7r-none-eabihf" => Some("arm-none-eabi"), "armv8r-none-eabihf" => Some("arm-none-eabi"), "thumbv6m-none-eabi" => Some("arm-none-eabi"), "thumbv7em-none-eabi" => Some("arm-none-eabi"), "thumbv7em-none-eabihf" => Some("arm-none-eabi"), "thumbv7m-none-eabi" => Some("arm-none-eabi"), "thumbv8m.base-none-eabi" => Some("arm-none-eabi"), "thumbv8m.main-none-eabi" => Some("arm-none-eabi"), "thumbv8m.main-none-eabihf" => Some("arm-none-eabi"), "x86_64-pc-windows-gnu" => Some("x86_64-w64-mingw32"), "x86_64-pc-windows-gnullvm" => Some("x86_64-w64-mingw32"), "x86_64-uwp-windows-gnu" => Some("x86_64-w64-mingw32"), "x86_64-rumprun-netbsd" => Some("x86_64-rumprun-netbsd"), "x86_64-unknown-linux-gnu" => self.find_working_gnu_prefix(&[ "x86_64-linux-gnu", // rustfmt wrap ]), // explicit None if not found, so caller knows to fall back "x86_64-unknown-linux-musl" => Some("musl"), "x86_64-unknown-netbsd" => Some("x86_64--netbsd"), _ => None, } .map(Cow::Borrowed) }) } /// Some platforms have multiple, compatible, canonical prefixes. Look through /// each possible prefix for a compiler that exists and return it. The prefixes /// should be ordered from most-likely to least-likely. fn find_working_gnu_prefix(&self, prefixes: &[&'static str]) -> Option<&'static str> { let suffix = if self.cpp { "-g++" } else { "-gcc" }; let extension = std::env::consts::EXE_SUFFIX; // Loop through PATH entries searching for each toolchain. This ensures that we // are more likely to discover the toolchain early on, because chances are good // that the desired toolchain is in one of the higher-priority paths. self.getenv("PATH") .as_ref() .and_then(|path_entries| { env::split_paths(path_entries).find_map(|path_entry| { for prefix in prefixes { let target_compiler = format!("{}{}{}", prefix, suffix, extension); if path_entry.join(&target_compiler).exists() { return Some(prefix); } } None }) }) .copied() // If no toolchain was found, provide the first toolchain that was passed in. // This toolchain has been shown not to exist, however it will appear in the // error that is shown to the user which should make it easier to search for // where it should be obtained. .or_else(|| prefixes.first().copied()) } fn get_target(&self) -> Result, Error> { match &self.target { Some(t) if Some(&**t) != self.getenv_unwrap_str("TARGET").ok().as_deref() => t.parse(), // Fetch target information from environment if not set, or if the // target was the same as the TARGET environment variable, in // case the user did `build.target(&env::var("TARGET").unwrap())`. _ => self .build_cache .target_info_parser .parse_from_cargo_environment_variables(), } } fn get_raw_target(&self) -> Result, Error> { match &self.target { Some(t) => Ok(Cow::Borrowed(t)), None => self.getenv_unwrap_str("TARGET").map(Cow::Owned), } } fn get_is_cross_compile(&self) -> Result { let target = self.get_raw_target()?; let host: Cow<'_, str> = match &self.host { Some(h) => Cow::Borrowed(h), None => Cow::Owned(self.getenv_unwrap_str("HOST")?), }; Ok(host != target) } fn get_opt_level(&self) -> Result, Error> { match &self.opt_level { Some(ol) => Ok(Cow::Borrowed(ol)), None => self.getenv_unwrap_str("OPT_LEVEL").map(Cow::Owned), } } fn get_debug(&self) -> bool { self.debug.unwrap_or_else(|| self.getenv_boolean("DEBUG")) } fn get_shell_escaped_flags(&self) -> bool { self.shell_escaped_flags .unwrap_or_else(|| self.getenv_boolean("CC_SHELL_ESCAPED_FLAGS")) } fn get_dwarf_version(&self) -> Option { // Tentatively matches the DWARF version defaults as of rustc 1.62. let target = self.get_target().ok()?; if matches!( target.os, "android" | "dragonfly" | "freebsd" | "netbsd" | "openbsd" ) || target.vendor == "apple" || (target.os == "windows" && target.env == "gnu") { Some(2) } else if target.os == "linux" { Some(4) } else { None } } fn get_force_frame_pointer(&self) -> bool { self.force_frame_pointer.unwrap_or_else(|| self.get_debug()) } fn get_out_dir(&self) -> Result, Error> { match &self.out_dir { Some(p) => Ok(Cow::Borrowed(&**p)), None => self .getenv("OUT_DIR") .as_deref() .map(PathBuf::from) .map(Cow::Owned) .ok_or_else(|| { Error::new( ErrorKind::EnvVarNotFound, "Environment variable OUT_DIR not defined.", ) }), } } #[allow(clippy::disallowed_methods)] fn getenv(&self, v: &str) -> Option> { // Returns true for environment variables cargo sets for build scripts: // https://doc.rust-lang.org/cargo/reference/environment-variables.html#environment-variables-cargo-sets-for-build-scripts // // This handles more of the vars than we actually use (it tries to check // complete-ish set), just to avoid needing maintenance if/when new // calls to `getenv`/`getenv_unwrap` are added. fn provided_by_cargo(envvar: &str) -> bool { match envvar { v if v.starts_with("CARGO") || v.starts_with("RUSTC") => true, "HOST" | "TARGET" | "RUSTDOC" | "OUT_DIR" | "OPT_LEVEL" | "DEBUG" | "PROFILE" | "NUM_JOBS" | "RUSTFLAGS" => true, _ => false, } } if let Some(val) = self.build_cache.env_cache.read().unwrap().get(v).cloned() { return val; } // Excluding `PATH` prevents spurious rebuilds on Windows, see // for details. if self.emit_rerun_if_env_changed && !provided_by_cargo(v) && v != "PATH" { self.cargo_output .print_metadata(&format_args!("cargo:rerun-if-env-changed={}", v)); } let r = env::var_os(v).map(Arc::from); self.cargo_output.print_metadata(&format_args!( "{} = {}", v, OptionOsStrDisplay(r.as_deref()) )); self.build_cache .env_cache .write() .unwrap() .insert(v.into(), r.clone()); r } /// get boolean flag that is either true or false fn getenv_boolean(&self, v: &str) -> bool { match self.getenv(v) { Some(s) => &*s != "0" && &*s != "false" && !s.is_empty(), None => false, } } fn getenv_unwrap(&self, v: &str) -> Result, Error> { match self.getenv(v) { Some(s) => Ok(s), None => Err(Error::new( ErrorKind::EnvVarNotFound, format!("Environment variable {} not defined.", v), )), } } fn getenv_unwrap_str(&self, v: &str) -> Result { let env = self.getenv_unwrap(v)?; env.to_str().map(String::from).ok_or_else(|| { Error::new( ErrorKind::EnvVarNotFound, format!("Environment variable {} is not valid utf-8.", v), ) }) } fn getenv_with_target_prefixes(&self, var_base: &str) -> Result, Error> { let target = self.get_raw_target()?; let kind = if self.get_is_cross_compile()? { "TARGET" } else { "HOST" }; let target_u = target.replace('-', "_"); let res = self .getenv(&format!("{}_{}", var_base, target)) .or_else(|| self.getenv(&format!("{}_{}", var_base, target_u))) .or_else(|| self.getenv(&format!("{}_{}", kind, var_base))) .or_else(|| self.getenv(var_base)); match res { Some(res) => Ok(res), None => Err(Error::new( ErrorKind::EnvVarNotFound, format!("Could not find environment variable {}.", var_base), )), } } fn envflags(&self, name: &str) -> Result, Error> { let env_os = self.getenv_with_target_prefixes(name)?; let env = env_os.to_string_lossy(); if self.get_shell_escaped_flags() { Ok(Shlex::new(&env).collect()) } else { Ok(env .split_ascii_whitespace() .map(ToString::to_string) .collect()) } } fn fix_env_for_apple_os(&self, cmd: &mut Command) -> Result<(), Error> { let target = self.get_target()?; if cfg!(target_os = "macos") && target.os == "macos" { // Additionally, `IPHONEOS_DEPLOYMENT_TARGET` must not be set when using the Xcode linker at // "/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld", // although this is apparently ignored when using the linker at "/usr/bin/ld". cmd.env_remove("IPHONEOS_DEPLOYMENT_TARGET"); } Ok(()) } fn apple_sdk_root_inner(&self, sdk: &str) -> Result, Error> { // Code copied from rustc's compiler/rustc_codegen_ssa/src/back/link.rs. if let Some(sdkroot) = self.getenv("SDKROOT") { let p = Path::new(&sdkroot); let does_sdkroot_contain = |strings: &[&str]| { let sdkroot_str = p.to_string_lossy(); strings.iter().any(|s| sdkroot_str.contains(s)) }; match sdk { // Ignore `SDKROOT` if it's clearly set for the wrong platform. "appletvos" if does_sdkroot_contain(&["TVSimulator.platform", "MacOSX.platform"]) => {} "appletvsimulator" if does_sdkroot_contain(&["TVOS.platform", "MacOSX.platform"]) => {} "iphoneos" if does_sdkroot_contain(&["iPhoneSimulator.platform", "MacOSX.platform"]) => {} "iphonesimulator" if does_sdkroot_contain(&["iPhoneOS.platform", "MacOSX.platform"]) => {} "macosx10.15" if does_sdkroot_contain(&["iPhoneOS.platform", "iPhoneSimulator.platform"]) => { } "watchos" if does_sdkroot_contain(&["WatchSimulator.platform", "MacOSX.platform"]) => {} "watchsimulator" if does_sdkroot_contain(&["WatchOS.platform", "MacOSX.platform"]) => {} "xros" if does_sdkroot_contain(&["XRSimulator.platform", "MacOSX.platform"]) => {} "xrsimulator" if does_sdkroot_contain(&["XROS.platform", "MacOSX.platform"]) => {} // Ignore `SDKROOT` if it's not a valid path. _ if !p.is_absolute() || p == Path::new("/") || !p.exists() => {} _ => return Ok(sdkroot), } } let sdk_path = run_output( self.cmd("xcrun") .arg("--show-sdk-path") .arg("--sdk") .arg(sdk), "xcrun", &self.cargo_output, )?; let sdk_path = match String::from_utf8(sdk_path) { Ok(p) => p, Err(_) => { return Err(Error::new( ErrorKind::IOError, "Unable to determine Apple SDK path.", )); } }; Ok(Arc::from(OsStr::new(sdk_path.trim()))) } fn apple_sdk_root(&self, target: &TargetInfo<'_>) -> Result, Error> { let sdk = target.apple_sdk_name(); if let Some(ret) = self .build_cache .apple_sdk_root_cache .read() .expect("apple_sdk_root_cache lock failed") .get(sdk) .cloned() { return Ok(ret); } let sdk_path = self.apple_sdk_root_inner(sdk)?; self.build_cache .apple_sdk_root_cache .write() .expect("apple_sdk_root_cache lock failed") .insert(sdk.into(), sdk_path.clone()); Ok(sdk_path) } fn apple_deployment_target(&self, target: &TargetInfo<'_>) -> Arc { let sdk = target.apple_sdk_name(); if let Some(ret) = self .build_cache .apple_versions_cache .read() .expect("apple_versions_cache lock failed") .get(sdk) .cloned() { return ret; } let default_deployment_from_sdk = || -> Option> { let version = run_output( self.cmd("xcrun") .arg("--show-sdk-version") .arg("--sdk") .arg(sdk), "xcrun", &self.cargo_output, ) .ok()?; Some(Arc::from(std::str::from_utf8(&version).ok()?.trim())) }; let deployment_from_env = |name: &str| -> Option> { // note that self.env isn't hit in production codepaths, its mostly just for tests which don't // set the real env self.env .iter() .find(|(k, _)| &**k == OsStr::new(name)) .map(|(_, v)| v) .cloned() .or_else(|| self.getenv(name))? .to_str() .map(Arc::from) }; // Determines if the acquired deployment target is too low to support modern C++ on some Apple platform. // // A long time ago they used libstdc++, but since macOS 10.9 and iOS 7 libc++ has been the library the SDKs provide to link against. // If a `cc`` config wants to use C++, we round up to these versions as the baseline. let maybe_cpp_version_baseline = |deployment_target_ver: Arc| -> Option> { if !self.cpp { return Some(deployment_target_ver); } let mut deployment_target = deployment_target_ver .split('.') .map(|v| v.parse::().expect("integer version")); match target.os { "macos" => { let major = deployment_target.next().unwrap_or(0); let minor = deployment_target.next().unwrap_or(0); // If below 10.9, we ignore it and let the SDK's target definitions handle it. if major == 10 && minor < 9 { self.cargo_output.print_warning(&format_args!( "macOS deployment target ({}) too low, it will be increased", deployment_target_ver )); return None; } } "ios" => { let major = deployment_target.next().unwrap_or(0); // If below 10.7, we ignore it and let the SDK's target definitions handle it. if major < 7 { self.cargo_output.print_warning(&format_args!( "iOS deployment target ({}) too low, it will be increased", deployment_target_ver )); return None; } } // watchOS, tvOS, visionOS, and others are all new enough that libc++ is their baseline. _ => {} } // If the deployment target met or exceeded the C++ baseline Some(deployment_target_ver) }; // The hardcoded minimums here are subject to change in a future compiler release, // and only exist as last resort fallbacks. Don't consider them stable. // `cc` doesn't use rustc's `--print deployment-target`` because the compiler's defaults // don't align well with Apple's SDKs and other third-party libraries that require ~generally~ higher // deployment targets. rustc isn't interested in those by default though so its fine to be different here. // // If no explicit target is passed, `cc` defaults to the current Xcode SDK's `DefaultDeploymentTarget` for better // compatibility. This is also the crate's historical behavior and what has become a relied-on value. // // The ordering of env -> XCode SDK -> old rustc defaults is intentional for performance when using // an explicit target. let version: Arc = match target.os { "macos" => deployment_from_env("MACOSX_DEPLOYMENT_TARGET") .and_then(maybe_cpp_version_baseline) .or_else(default_deployment_from_sdk) .unwrap_or_else(|| { if target.arch == "aarch64" { "11.0".into() } else { let default: Arc = Arc::from("10.7"); maybe_cpp_version_baseline(default.clone()).unwrap_or(default) } }), "ios" => deployment_from_env("IPHONEOS_DEPLOYMENT_TARGET") .and_then(maybe_cpp_version_baseline) .or_else(default_deployment_from_sdk) .unwrap_or_else(|| "7.0".into()), "watchos" => deployment_from_env("WATCHOS_DEPLOYMENT_TARGET") .or_else(default_deployment_from_sdk) .unwrap_or_else(|| "5.0".into()), "tvos" => deployment_from_env("TVOS_DEPLOYMENT_TARGET") .or_else(default_deployment_from_sdk) .unwrap_or_else(|| "9.0".into()), "visionos" => deployment_from_env("XROS_DEPLOYMENT_TARGET") .or_else(default_deployment_from_sdk) .unwrap_or_else(|| "1.0".into()), os => unreachable!("unknown Apple OS: {}", os), }; self.build_cache .apple_versions_cache .write() .expect("apple_versions_cache lock failed") .insert(sdk.into(), version.clone()); version } fn wasi_sysroot(&self) -> Result, Error> { if let Some(wasi_sysroot_path) = self.getenv("WASI_SYSROOT") { Ok(wasi_sysroot_path) } else { Err(Error::new( ErrorKind::EnvVarNotFound, "Environment variable WASI_SYSROOT not defined. Download sysroot from GitHub & setup environment variable WASI_SYSROOT targeting the folder.", )) } } fn cuda_file_count(&self) -> usize { self.files .iter() .filter(|file| file.extension() == Some(OsStr::new("cu"))) .count() } fn which(&self, tool: &Path, path_entries: Option<&OsStr>) -> Option { fn check_exe(mut exe: PathBuf) -> Option { let exe_ext = std::env::consts::EXE_EXTENSION; let check = exe.exists() || (!exe_ext.is_empty() && exe.set_extension(exe_ext) && exe.exists()); check.then_some(exe) } // Loop through PATH entries searching for the |tool|. let find_exe_in_path = |path_entries: &OsStr| -> Option { env::split_paths(path_entries).find_map(|path_entry| check_exe(path_entry.join(tool))) }; // If |tool| is not just one "word," assume it's an actual path... if tool.components().count() > 1 { check_exe(PathBuf::from(tool)) } else { path_entries .and_then(find_exe_in_path) .or_else(|| find_exe_in_path(&self.getenv("PATH")?)) } } /// search for |prog| on 'programs' path in '|cc| -print-search-dirs' output fn search_programs( &self, cc: &mut Command, prog: &Path, cargo_output: &CargoOutput, ) -> Option { let search_dirs = run_output( cc.arg("-print-search-dirs"), "cc", // this doesn't concern the compilation so we always want to show warnings. cargo_output, ) .ok()?; // clang driver appears to be forcing UTF-8 output even on Windows, // hence from_utf8 is assumed to be usable in all cases. let search_dirs = std::str::from_utf8(&search_dirs).ok()?; for dirs in search_dirs.split(['\r', '\n']) { if let Some(path) = dirs.strip_prefix("programs: =") { return self.which(prog, Some(OsStr::new(path))); } } None } fn windows_registry_find(&self, target: &TargetInfo<'_>, tool: &str) -> Option { self.windows_registry_find_tool(target, tool) .map(|c| c.to_command()) } fn windows_registry_find_tool(&self, target: &TargetInfo<'_>, tool: &str) -> Option { struct BuildEnvGetter<'s>(&'s Build); impl windows_registry::EnvGetter for BuildEnvGetter<'_> { fn get_env(&self, name: &str) -> Option { self.0.getenv(name).map(windows_registry::Env::Arced) } } if target.env != "msvc" { return None; } windows_registry::find_tool_inner(target.full_arch, tool, &BuildEnvGetter(self)) } } impl Default for Build { fn default() -> Build { Build::new() } } fn fail(s: &str) -> ! { eprintln!("\n\nerror occurred in cc-rs: {}\n\n", s); std::process::exit(1); } // Use by default minimum available API level // See note about naming here // https://android.googlesource.com/platform/ndk/+/refs/heads/ndk-release-r21/docs/BuildSystemMaintainers.md#Clang static NEW_STANDALONE_ANDROID_COMPILERS: [&str; 4] = [ "aarch64-linux-android21-clang", "armv7a-linux-androideabi16-clang", "i686-linux-android16-clang", "x86_64-linux-android21-clang", ]; // New "standalone" C/C++ cross-compiler executables from recent Android NDK // are just shell scripts that call main clang binary (from Android NDK) with // proper `--target` argument. // // For example, armv7a-linux-androideabi16-clang passes // `--target=armv7a-linux-androideabi16` to clang. // So to construct proper command line check if // `--target` argument would be passed or not to clang fn android_clang_compiler_uses_target_arg_internally(clang_path: &Path) -> bool { if let Some(filename) = clang_path.file_name() { if let Some(filename_str) = filename.to_str() { if let Some(idx) = filename_str.rfind('-') { return filename_str.split_at(idx).0.contains("android"); } } } false } // FIXME: Use parsed target. fn autodetect_android_compiler(raw_target: &str, gnu: &str, clang: &str) -> String { let new_clang_key = match raw_target { "aarch64-linux-android" => Some("aarch64"), "armv7-linux-androideabi" => Some("armv7a"), "i686-linux-android" => Some("i686"), "x86_64-linux-android" => Some("x86_64"), _ => None, }; let new_clang = new_clang_key .map(|key| { NEW_STANDALONE_ANDROID_COMPILERS .iter() .find(|x| x.starts_with(key)) }) .unwrap_or(None); if let Some(new_clang) = new_clang { if Command::new(new_clang).output().is_ok() { return (*new_clang).into(); } } let target = raw_target .replace("armv7neon", "arm") .replace("armv7", "arm") .replace("thumbv7neon", "arm") .replace("thumbv7", "arm"); let gnu_compiler = format!("{}-{}", target, gnu); let clang_compiler = format!("{}-{}", target, clang); // On Windows, the Android clang compiler is provided as a `.cmd` file instead // of a `.exe` file. `std::process::Command` won't run `.cmd` files unless the // `.cmd` is explicitly appended to the command name, so we do that here. let clang_compiler_cmd = format!("{}-{}.cmd", target, clang); // Check if gnu compiler is present // if not, use clang if Command::new(&gnu_compiler).output().is_ok() { gnu_compiler } else if cfg!(windows) && Command::new(&clang_compiler_cmd).output().is_ok() { clang_compiler_cmd } else { clang_compiler } } // Rust and clang/cc don't agree on how to name the target. fn map_darwin_target_from_rust_to_compiler_architecture<'a>(target: &TargetInfo<'a>) -> &'a str { match target.full_arch { "aarch64" => "arm64", "arm64_32" => "arm64_32", "arm64e" => "arm64e", "armv7k" => "armv7k", "armv7s" => "armv7s", "i386" => "i386", "i686" => "i386", "powerpc" => "ppc", "powerpc64" => "ppc64", "x86_64" => "x86_64", "x86_64h" => "x86_64h", arch => arch, } } #[derive(Clone, Copy, PartialEq)] enum AsmFileExt { /// `.asm` files. On MSVC targets, we assume these should be passed to MASM /// (`ml{,64}.exe`). DotAsm, /// `.s` or `.S` files, which do not have the special handling on MSVC targets. DotS, } impl AsmFileExt { fn from_path(file: &Path) -> Option { if let Some(ext) = file.extension() { if let Some(ext) = ext.to_str() { let ext = ext.to_lowercase(); match &*ext { "asm" => return Some(AsmFileExt::DotAsm), "s" => return Some(AsmFileExt::DotS), _ => return None, } } } None } } /// Returns true if `cc` has been disabled by `CC_FORCE_DISABLE`. fn is_disabled() -> bool { static CACHE: AtomicU8 = AtomicU8::new(0); let val = CACHE.load(Relaxed); // We manually cache the environment var, since we need it in some places // where we don't have access to a `Build` instance. #[allow(clippy::disallowed_methods)] fn compute_is_disabled() -> bool { match std::env::var_os("CC_FORCE_DISABLE") { // Not set? Not disabled. None => false, // Respect `CC_FORCE_DISABLE=0` and some simple synonyms, otherwise // we're disabled. This intentionally includes `CC_FORCE_DISABLE=""` Some(v) => &*v != "0" && &*v != "false" && &*v != "no", } } match val { 2 => true, 1 => false, 0 => { let truth = compute_is_disabled(); let encoded_truth = if truth { 2u8 } else { 1 }; // Might race against another thread, but we'd both be setting the // same value so it should be fine. CACHE.store(encoded_truth, Relaxed); truth } _ => unreachable!(), } } /// Automates the `if is_disabled() { return error }` check and ensures /// we produce a consistent error message for it. fn check_disabled() -> Result<(), Error> { if is_disabled() { return Err(Error::new( ErrorKind::Disabled, "the `cc` crate's functionality has been disabled by the `CC_FORCE_DISABLE` environment variable." )); } Ok(()) } #[cfg(test)] mod tests { use super::*; #[test] fn test_android_clang_compiler_uses_target_arg_internally() { for version in 16..21 { assert!(android_clang_compiler_uses_target_arg_internally( &PathBuf::from(format!("armv7a-linux-androideabi{}-clang", version)) )); assert!(android_clang_compiler_uses_target_arg_internally( &PathBuf::from(format!("armv7a-linux-androideabi{}-clang++", version)) )); } assert!(!android_clang_compiler_uses_target_arg_internally( &PathBuf::from("clang-i686-linux-android") )); assert!(!android_clang_compiler_uses_target_arg_internally( &PathBuf::from("clang") )); assert!(!android_clang_compiler_uses_target_arg_internally( &PathBuf::from("clang++") )); } }