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Diffstat (limited to 'vendor/cc/src/lib.rs')
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diff --git a/vendor/cc/src/lib.rs b/vendor/cc/src/lib.rs new file mode 100644 index 00000000..78e12f87 --- /dev/null +++ b/vendor/cc/src/lib.rs @@ -0,0 +1,4335 @@ +//! 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. `<var>_<target>` - for example, `CC_x86_64-unknown-linux-gnu` +//! 2. `<var>_<target_with_underscores>` - for example, `CC_x86_64_unknown_linux_gnu` +//! 3. `<build-kind>_<var>` - for example, `HOST_CC` or `TARGET_CFLAGS` +//! 4. `<var>` - 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 name 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 name 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, Stdio}; +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::{CompilerFamilyLookupCache, ToolFamily}; + +mod tempfile; + +mod utilities; +use utilities::*; + +mod flags; +use flags::*; + +#[derive(Debug, Eq, PartialEq, Hash)] +struct CompilerFlag { + compiler: Box<Path>, + flag: Box<OsStr>, +} + +type Env = Option<Arc<OsStr>>; + +#[derive(Debug, Default)] +struct BuildCache { + env_cache: RwLock<HashMap<Box<str>, Env>>, + apple_sdk_root_cache: RwLock<HashMap<Box<str>, Arc<OsStr>>>, + apple_versions_cache: RwLock<HashMap<Box<str>, Arc<str>>>, + cached_compiler_family: RwLock<CompilerFamilyLookupCache>, + known_flag_support_status_cache: RwLock<HashMap<CompilerFlag, bool>>, + 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<Arc<Path>>, + definitions: Vec<(Arc<str>, Option<Arc<str>>)>, + objects: Vec<Arc<Path>>, + flags: Vec<Arc<OsStr>>, + flags_supported: Vec<Arc<OsStr>>, + ar_flags: Vec<Arc<OsStr>>, + asm_flags: Vec<Arc<OsStr>>, + no_default_flags: bool, + files: Vec<Arc<Path>>, + cpp: bool, + cpp_link_stdlib: Option<Option<Arc<str>>>, + cpp_set_stdlib: Option<Arc<str>>, + cuda: bool, + cudart: Option<Arc<str>>, + ccbin: bool, + std: Option<Arc<str>>, + target: Option<Arc<str>>, + /// The host compiler. + /// + /// Try to not access this directly, and instead prefer `cfg!(...)`. + host: Option<Arc<str>>, + out_dir: Option<Arc<Path>>, + opt_level: Option<Arc<str>>, + debug: Option<bool>, + force_frame_pointer: Option<bool>, + env: Vec<(Arc<OsStr>, Arc<OsStr>)>, + compiler: Option<Arc<Path>>, + archiver: Option<Arc<Path>>, + ranlib: Option<Arc<Path>>, + cargo_output: CargoOutput, + link_lib_modifiers: Vec<Arc<OsStr>>, + pic: Option<bool>, + use_plt: Option<bool>, + static_crt: Option<bool>, + shared_flag: Option<bool>, + static_flag: Option<bool>, + warnings_into_errors: bool, + warnings: Option<bool>, + extra_warnings: Option<bool>, + emit_rerun_if_env_changed: bool, + shell_escaped_flags: Option<bool>, + build_cache: Arc<BuildCache>, + 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<Cow<'static, str>>) -> Error { + Error { + kind, + message: message.into(), + } + } +} + +impl From<io::Error> 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 } + } +} + +/// Configure the builder. +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<P: AsRef<Path>>(&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<P>(&mut self, dirs: P) -> &mut Build + where + P: IntoIterator, + P::Item: AsRef<Path>, + { + 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<Option<&'a str>>>(&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<P: AsRef<Path>>(&mut self, obj: P) -> &mut Build { + self.objects.push(obj.as_ref().into()); + self + } + + /// Add arbitrary object files to link in + pub fn objects<P>(&mut self, objs: P) -> &mut Build + where + P: IntoIterator, + P::Item: AsRef<Path>, + { + 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<OsStr>) -> &mut Build { + self.flags.push(flag.as_ref().into()); + self + } + + /// Add multiple flags to the invocation of the compiler. + /// This is equivalent to calling [`flag`](Self::flag) for each item in the iterator. + /// + /// # Example + /// ```no_run + /// cc::Build::new() + /// .file("src/foo.c") + /// .flags(["-Wall", "-Wextra"]) + /// .compile("foo"); + /// ``` + pub fn flags<Iter>(&mut self, flags: Iter) -> &mut Build + where + Iter: IntoIterator, + Iter::Item: AsRef<OsStr>, + { + for flag in flags { + self.flag(flag); + } + 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<OsStr>) -> &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<OsStr>) -> &mut Build { + self.asm_flags.push(flag.as_ref().into()); + self + } + + /// 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<OsStr>) -> &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)?.ok_or_else(|| { + Error::new( + ErrorKind::EnvVarNotFound, + format!("could not find environment variable {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<P: AsRef<Path>>(&mut self, p: P) -> &mut Build { + self.files.push(p.as_ref().into()); + self + } + + /// Add files which will be compiled + pub fn files<P>(&mut self, p: P) -> &mut Build + where + P: IntoIterator, + P::Item: AsRef<Path>, + { + for file in p.into_iter() { + self.file(file); + } + self + } + + /// Get the files which will be compiled + pub fn get_files(&self) -> impl Iterator<Item = &Path> { + 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 <https://docs.nvidia.com/cuda/cuda-compiler-driver-nvcc/> + /// 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<Option<&'a str>>>( + &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<Option<&'a str>>>( + &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<P: AsRef<Path>>(&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<P: AsRef<Path>>(&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<P: AsRef<Path>>(&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<P: AsRef<Path>>(&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 <https://doc.rust-lang.org/rustc/command-line-arguments.html#-l-link-the-generated-crate-to-a-native-library> + /// for the list of modifiers accepted by rustc. + pub fn link_lib_modifier(&mut self, link_lib_modifier: impl AsRef<OsStr>) -> &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<A, B>(&mut self, a: A, b: B) -> &mut Build + where + A: AsRef<OsStr>, + B: AsRef<OsStr>, + { + self.env.push((a.as_ref().into(), b.as_ref().into())); + self + } +} + +/// Invoke or fetch the compiler or archiver. +impl Build { + /// 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<OsStr>) -> Result<bool, Error> { + self.is_flag_supported_inner( + flag.as_ref(), + &self.get_base_compiler()?, + &self.get_target()?, + ) + } + + fn ensure_check_file(&self) -> Result<PathBuf, Error> { + 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) + } + + fn is_flag_supported_inner( + &self, + flag: &OsStr, + tool: &Tool, + target: &TargetInfo<'_>, + ) -> Result<bool, Error> { + 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"); + command_add_output_file( + &mut cmd, + &obj, + CmdAddOutputFileArgs { + cuda: self.cuda, + is_assembler_msvc: false, + msvc: compiler.is_like_msvc(), + clang: compiler.is_like_clang(), + gnu: compiler.is_like_gnu(), + is_asm: false, + is_arm, + }, + ); + + // Checking for compiler flags does not require linking (and we _must_ + // avoid making it do so, since it breaks cross-compilation when the C + // compiler isn't configured to be able to link). + // https://github.com/rust-lang/cc-rs/issues/1423 + cmd.arg("-c"); + + if compiler.supports_path_delimiter() { + cmd.arg("--"); + } + + cmd.arg(&src); + + if compiler.is_like_msvc() { + // On MSVC we need to make sure the LIB directory is included + // so the CRT can be found. + for (key, value) in &tool.env { + if key == "LIB" { + cmd.env("LIB", value); + break; + } + } + } + + let output = cmd.current_dir(out_dir).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) + } + + /// 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.arch == "wasm32" { + 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()? + )); + } + } else if target.os == "linux" { + let musl_sysroot = self.wasm_musl_sysroot().unwrap(); + self.cargo_output.print_metadata(&format_args!( + "cargo:rustc-flags=-L {}/lib -lstatic=c++ -lstatic=c++abi", + Path::new(&musl_sysroot).display(), + )); + } + } + } + + 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<PathBuf> { + 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<Vec<PathBuf>, 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 = self.create_compile_object_cmd(obj)?; + run(&mut cmd, &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, 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, child, _token)| { + match try_wait_on_child(cmd, &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 = self.create_compile_object_cmd(obj)?; + let token = tokens.acquire().await?; + let mut child = spawn(&mut cmd, &self.cargo_output)?; + let mut stderr_forwarder = StderrForwarder::new(&mut child); + stderr_forwarder.set_non_blocking()?; + + cell_update(&pendings, |mut pendings| { + pendings.push((cmd, 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<T, F>(cell: &Cell<T>, 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 = self.create_compile_object_cmd(obj)?; + run(&mut cmd, &self.cargo_output)?; + } + + Ok(()) + } + + fn create_compile_object_cmd(&self, obj: &Object) -> Result<Command, 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 is_assembler_msvc = msvc && asm_ext == Some(AsmFileExt::DotAsm); + let mut cmd = if is_assembler_msvc { + self.msvc_macro_assembler()? + } else { + let mut cmd = compiler.to_command(); + for (a, b) in self.env.iter() { + cmd.env(a, b); + } + cmd + }; + 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: compiler.is_like_clang(), + gnu: compiler.is_like_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) + } + + /// This will return a result instead of panicking; see [`Self::expand()`] for + /// the complete description. + pub fn try_expand(&self) -> Result<Vec<u8>, 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)); + + run_output(&mut cmd, &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<u8> { + 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<Tool, Error> { + let opt_level = self.get_opt_level()?; + let target = self.get_target()?; + + let mut cmd = self.get_base_compiler()?; + + // The flags below are added in roughly the following order: + // 1. Default flags + // - Controlled by `cc-rs`. + // 2. `rustc`-inherited flags + // - Controlled by `rustc`. + // 3. Builder flags + // - Controlled by the developer using `cc-rs` in e.g. their `build.rs`. + // 4. Environment flags + // - Controlled by the end user. + // + // This is important to allow later flags to override previous ones. + + // Copied from <https://github.com/rust-lang/rust/blob/5db81020006d2920fc9c62ffc0f4322f90bffa04/compiler/rustc_codegen_ssa/src/back/linker.rs#L27-L38> + // + // 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())); + } + + // 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)?; + } + + // Specify various flags that are not considered part of the default flags above. + // FIXME(madsmtm): Should these be considered part of the defaults? If no, why not? + 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 self.warnings_into_errors { + let warnings_to_errors_flag = cmd.family.warnings_to_errors_flag().into(); + cmd.push_cc_arg(warnings_to_errors_flag); + } + + // 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. + let envflags = self.envflags(if self.cpp { "CXXFLAGS" } else { "CFLAGS" })?; + if self.warnings.unwrap_or(envflags.is_none()) { + let wflags = cmd.family.warnings_flags().into(); + cmd.push_cc_arg(wflags); + } + if self.extra_warnings.unwrap_or(envflags.is_none()) { + if let Some(wflags) = cmd.family.extra_warnings_flags() { + cmd.push_cc_arg(wflags.into()); + } + } + + // Add cc flags inherited from matching rustc flags. + if self.inherit_rustflags { + self.add_inherited_rustflags(&mut cmd, &target)?; + } + + // Set flags configured in the builder (do this second-to-last, to allow these to override + // everything above). + for flag in self.flags.iter() { + cmd.args.push((**flag).into()); + } + 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()); + } + } + + // Set flags from the environment (do this last, to allow these to override everything else). + if let Some(flags) = &envflags { + for arg in flags { + cmd.push_cc_arg(arg.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: + // <https://github.com/rust-lang/rust/blob/1.82.0/compiler/rustc_target/src/spec/base/wasm.rs#L101-L108> + 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: + // <https://github.com/rust-lang/rust/blob/1.82.0/compiler/rustc_target/src/spec/base/wasm.rs#L72-L77> + 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.full_arch { + "x86" | "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 target 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 name + // 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()); + } + } else if target.arch == "wasm32" && target.os == "linux" { + for x in &[ + "atomics", + "bulk-memory", + "mutable-globals", + "sign-ext", + "exception-handling", + ] { + cmd.push_cc_arg(format!("-m{x}").into()); + } + for x in &["wasm-exceptions", "declspec"] { + cmd.push_cc_arg(format!("-f{x}").into()); + } + let musl_sysroot = self.wasm_musl_sysroot().unwrap(); + cmd.push_cc_arg( + format!("--sysroot={}", Path::new(&musl_sysroot).display()).into(), + ); + cmd.push_cc_arg("-pthread".into()); + } + // Pass `--target` with the LLVM target to configure Clang for cross-compiling. + // + // This is **required** for cross-compilation, as it's the only flag that + // consistently forces Clang to change the "toolchain" that is responsible for + // parsing target-specific flags: + // https://github.com/rust-lang/cc-rs/issues/1388 + // https://github.com/llvm/llvm-project/blob/llvmorg-19.1.7/clang/lib/Driver/Driver.cpp#L1359-L1360 + // https://github.com/llvm/llvm-project/blob/llvmorg-19.1.7/clang/lib/Driver/Driver.cpp#L6347-L6532 + // + // This can be confusing, because on e.g. host macOS, you can usually get by + // with `-arch` and `-mtargetos=`. But that only works because the _default_ + // toolchain is `Darwin`, which enables parsing of darwin-specific options. + // + // NOTE: In the past, we passed the deployment version in here on all Apple + // targets, but versioned targets were found to have poor compatibility with + // older versions of Clang, especially when it comes to configuration files: + // https://github.com/rust-lang/cc-rs/issues/1278 + // + // So instead, we pass the deployment target with `-m*-version-min=`, and only + // pass it here on visionOS and Mac Catalyst where that option does not exist: + // https://github.com/rust-lang/cc-rs/issues/1383 + let version = if target.os == "visionos" || target.abi == "macabi" { + Some(self.apple_deployment_target(target)) + } else { + None + }; + + let clang_target = + target.llvm_target(&self.get_raw_target()?, version.as_deref()); + cmd.push_cc_arg(format!("--target={clang_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()); + // See + // <https://learn.microsoft.com/en-us/cpp/build/reference/arch-x86?view=msvc-170>. + // + // NOTE: Rust officially supported Windows targets all require SSE2 as part + // of baseline target features. + // + // NOTE: The same applies for STL. See: - + // <https://github.com/microsoft/STL/issues/3922>, and - + // <https://github.com/microsoft/STL/pull/4741>. + cmd.push_cc_arg("-arch:SSE2".into()); + } else { + cmd.push_cc_arg( + format!( + "--target={}", + target.llvm_target(&self.get_raw_target()?, None) + ) + .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 == "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 msvc_macro_assembler(&self) -> Result<Command, 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::<i32>() { + 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) + } + + 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, &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 = self.try_get_archiver()?; + + // 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), &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.try_get_archiver_and_flags()?; + 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, &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), &self.cargo_output)?; + } + + Ok(()) + } + + fn apple_flags(&self, cmd: &mut Tool) -> Result<(), Error> { + let target = self.get_target()?; + + // This is a Darwin/Apple-specific flag that works both on GCC and Clang, but it is only + // necessary on GCC since we specify `-target` on Clang. + // https://gcc.gnu.org/onlinedocs/gcc/Darwin-Options.html#:~:text=arch + // https://clang.llvm.org/docs/CommandGuide/clang.html#cmdoption-arch + if cmd.is_like_gnu() { + let arch = map_darwin_target_from_rust_to_compiler_architecture(&target); + cmd.args.push("-arch".into()); + cmd.args.push(arch.into()); + } + + // Pass the deployment target via `-mmacosx-version-min=`, `-miphoneos-version-min=` and + // similar. Also necessary on GCC, as it forces a compilation error if the compiler is not + // configured for Darwin: https://gcc.gnu.org/onlinedocs/gcc/Darwin-Options.html + // + // On visionOS and Mac Catalyst, there is no -m*-version-min= flag: + // https://github.com/llvm/llvm-project/issues/88271 + // And the workaround to use `-mtargetos=` cannot be used with the `--target` flag that we + // otherwise specify. So we avoid emitting that, and put the version in `--target` instead. + if cmd.is_like_gnu() || !(target.os == "visionos" || target.abi == "macabi") { + 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()); + cmd.env + .push(("SDKROOT".into(), 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<P: AsRef<OsStr>>(&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<Tool, Error> { + 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<Tool> = self + .env_tool(env) + .map(|(tool, wrapper, args)| { + // 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_args( + tool, + args.clone(), + &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, + vec![], + 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::<u32>() { + 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<Arc<OsStr>> { + // 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<Arc<OsStr>>, Vec<String>)> { + 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::<OsStr>::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<Option<Cow<'_, Path>>, 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++")))) + } + } + } + } + } + + /// 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<Command, Error> { + 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 Some(flags) = self.envflags("ARFLAGS")? { + any_flags = true; + 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<Command, Error> { + let mut cmd = self.get_base_ranlib()?; + if let Some(flags) = self.envflags("RANLIBFLAGS")? { + cmd.args(flags); + } + Ok(cmd) + } + + fn get_base_ranlib(&self) -> Result<Command, Error> { + 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<Command> = 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 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 target.os == "vxworks" { + name = format!("wr-{}", tool).into(); + self.cmd(&name) + } else if target.os == "nto" { + // Ref: https://www.qnx.com/developers/docs/8.0/com.qnx.doc.neutrino.utilities/topic/a/ar.html + name = match target.full_arch { + "i586" => format!("ntox86-{}", tool).into(), + "x86" | "aarch64" | "x86_64" => { + format!("nto{}-{}", target.arch, tool).into() + } + _ => { + return Err(Error::new( + ErrorKind::InvalidTarget, + format!("Unknown architecture for Neutrino QNX: {}", target.arch), + )) + } + }; + self.cmd(&name) + } else if self.get_is_cross_compile()? { + match self.prefix_for_target(&self.get_raw_target()?) { + Some(prefix) => { + // 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 chosen = ["", "-gcc"] + .iter() + .filter_map(|infix| { + let target_p = format!("{prefix}{infix}-{tool}"); + let status = Command::new(&target_p) + .arg("--version") + .stdin(Stdio::null()) + .stdout(Stdio::null()) + .stderr(Stdio::null()) + .status() + .ok()?; + status.success().then_some(target_p) + }) + .next() + .unwrap_or_else(|| tool.to_string()); + name = chosen.into(); + self.cmd(&name) + } + None => { + name = tool.into(); + self.cmd(&name) + } + } + } else { + name = tool.into(); + self.cmd(&name) + } + } + }; + + Ok((tool, name)) + } + + // FIXME: Use parsed target instead of raw target. + fn prefix_for_target(&self, target: &str) -> Option<Cow<'static, str>> { + // 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("powerpc64-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" => { + self.find_working_gnu_prefix(&["x86_64-linux-musl", "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<TargetInfo<'_>, Error> { + match &self.target { + Some(t) if Some(&**t) != self.getenv_unwrap_str("TARGET").ok().as_deref() => { + TargetInfo::from_rustc_target(t) + } + // 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<Cow<'_, str>, 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<bool, Error> { + 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<Cow<'_, str>, 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<u32> { + // 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<Cow<'_, Path>, 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<Arc<OsStr>> { + // 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 + // <https://github.com/rust-lang/cc-rs/pull/1215> 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<Arc<OsStr>, 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<String, Error> { + 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), + ) + }) + } + + /// The list of environment variables to check for a given env, in order of priority. + fn target_envs(&self, env: &str) -> Result<[String; 4], Error> { + let target = self.get_raw_target()?; + let kind = if self.get_is_cross_compile()? { + "TARGET" + } else { + "HOST" + }; + let target_u = target.replace('-', "_"); + + Ok([ + format!("{env}_{target}"), + format!("{env}_{target_u}"), + format!("{kind}_{env}"), + env.to_string(), + ]) + } + + /// Get a single-valued environment variable with target variants. + fn getenv_with_target_prefixes(&self, env: &str) -> Result<Arc<OsStr>, Error> { + // Take from first environment variable in the environment. + let res = self + .target_envs(env)? + .iter() + .filter_map(|env| self.getenv(env)) + .next(); + + match res { + Some(res) => Ok(res), + None => Err(Error::new( + ErrorKind::EnvVarNotFound, + format!("could not find environment variable {env}"), + )), + } + } + + /// Get values from CFLAGS-style environment variable. + fn envflags(&self, env: &str) -> Result<Option<Vec<String>>, Error> { + // Collect from all environment variables, in reverse order as in + // `getenv_with_target_prefixes` precedence (so that `CFLAGS_$TARGET` + // can override flags in `TARGET_CFLAGS`, which overrides those in + // `CFLAGS`). + let mut any_set = false; + let mut res = vec![]; + for env in self.target_envs(env)?.iter().rev() { + if let Some(var) = self.getenv(env) { + any_set = true; + + let var = var.to_string_lossy(); + if self.get_shell_escaped_flags() { + res.extend(Shlex::new(&var)); + } else { + res.extend(var.split_ascii_whitespace().map(ToString::to_string)); + } + } + } + + Ok(if any_set { Some(res) } else { None }) + } + + 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<Arc<OsStr>, 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), + &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<Arc<OsStr>, 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<str> { + 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<Arc<str>> { + let version = run_output( + self.cmd("xcrun") + .arg("--show-sdk-version") + .arg("--sdk") + .arg(sdk), + &self.cargo_output, + ) + .ok()?; + + Some(Arc::from(std::str::from_utf8(&version).ok()?.trim())) + }; + + let deployment_from_env = |name: &str| -> Option<Arc<str>> { + // 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<str>| -> Option<Arc<str>> { + if !self.cpp { + return Some(deployment_target_ver); + } + + let mut deployment_target = deployment_target_ver + .split('.') + .map(|v| v.parse::<u32>().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<str> = 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<str> = 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 wasm_musl_sysroot(&self) -> Result<Arc<OsStr>, Error> { + if let Some(musl_sysroot_path) = self.getenv("WASM_MUSL_SYSROOT") { + Ok(musl_sysroot_path) + } else { + Err(Error::new( + ErrorKind::EnvVarNotFound, + "Environment variable WASM_MUSL_SYSROOT not defined for wasm32. Download sysroot from GitHub & setup environment variable MUSL_SYSROOT targeting the folder.", + )) + } + } + + fn wasi_sysroot(&self) -> Result<Arc<OsStr>, 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<PathBuf> { + fn check_exe(mut exe: PathBuf) -> Option<PathBuf> { + 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<PathBuf> { + 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<PathBuf> { + let search_dirs = run_output( + cc.arg("-print-search-dirs"), + // 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<Command> { + self.windows_registry_find_tool(target, tool) + .map(|c| c.to_command()) + } + + fn windows_registry_find_tool(&self, target: &TargetInfo<'_>, tool: &str) -> Option<Tool> { + struct BuildEnvGetter<'s>(&'s Build); + + impl windows_registry::EnvGetter for BuildEnvGetter<'_> { + fn get_env(&self, name: &str) -> Option<windows_registry::Env> { + 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<Self> { + 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++") + )); + } +} |