| // Copyright 2014-2015 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| //! [Flexible target specification.](https://github.com/rust-lang/rfcs/pull/131) |
| //! |
| //! Rust targets a wide variety of usecases, and in the interest of flexibility, |
| //! allows new target triples to be defined in configuration files. Most users |
| //! will not need to care about these, but this is invaluable when porting Rust |
| //! to a new platform, and allows for an unprecedented level of control over how |
| //! the compiler works. |
| //! |
| //! # Using custom targets |
| //! |
| //! A target triple, as passed via `rustc --target=TRIPLE`, will first be |
| //! compared against the list of built-in targets. This is to ease distributing |
| //! rustc (no need for configuration files) and also to hold these built-in |
| //! targets as immutable and sacred. If `TRIPLE` is not one of the built-in |
| //! targets, rustc will check if a file named `TRIPLE` exists. If it does, it |
| //! will be loaded as the target configuration. If the file does not exist, |
| //! rustc will search each directory in the environment variable |
| //! `RUST_TARGET_PATH` for a file named `TRIPLE.json`. The first one found will |
| //! be loaded. If no file is found in any of those directories, a fatal error |
| //! will be given. `RUST_TARGET_PATH` includes `/etc/rustc` as its last entry, |
| //! to be searched by default. |
| //! |
| //! Projects defining their own targets should use |
| //! `--target=path/to/my-awesome-platform.json` instead of adding to |
| //! `RUST_TARGET_PATH`. |
| //! |
| //! # Defining a new target |
| //! |
| //! Targets are defined using [JSON](http://json.org/). The `Target` struct in |
| //! this module defines the format the JSON file should take, though each |
| //! underscore in the field names should be replaced with a hyphen (`-`) in the |
| //! JSON file. Some fields are required in every target specification, such as |
| //! `data-layout`, `llvm-target`, `target-endian`, `target-pointer-width`, and |
| //! `arch`. In general, options passed to rustc with `-C` override the target's |
| //! settings, though `target-feature` and `link-args` will *add* to the list |
| //! specified by the target, rather than replace. |
| |
| use serialize::json::Json; |
| use std::default::Default; |
| use std::io::prelude::*; |
| use syntax::abi; |
| |
| mod android_base; |
| mod apple_base; |
| mod apple_ios_base; |
| mod bitrig_base; |
| mod dragonfly_base; |
| mod freebsd_base; |
| mod linux_base; |
| mod openbsd_base; |
| mod netbsd_base; |
| mod windows_base; |
| mod windows_msvc_base; |
| |
| /// Everything `rustc` knows about how to compile for a specific target. |
| /// |
| /// Every field here must be specified, and has no default value. |
| #[derive(Clone, Debug)] |
| pub struct Target { |
| /// Target triple to pass to LLVM. |
| pub llvm_target: String, |
| /// String to use as the `target_endian` `cfg` variable. |
| pub target_endian: String, |
| /// String to use as the `target_pointer_width` `cfg` variable. |
| pub target_pointer_width: String, |
| /// OS name to use for conditional compilation. |
| pub target_os: String, |
| /// Environment name to use for conditional compilation. |
| pub target_env: String, |
| /// Vendor name to use for conditional compilation. |
| pub target_vendor: String, |
| /// Architecture to use for ABI considerations. Valid options: "x86", "x86_64", "arm", |
| /// "aarch64", "mips", "powerpc", "powerpc64" and "powerpc64le". "mips" includes "mipsel". |
| pub arch: String, |
| /// Optional settings with defaults. |
| pub options: TargetOptions, |
| } |
| |
| /// Optional aspects of a target specification. |
| /// |
| /// This has an implementation of `Default`, see each field for what the default is. In general, |
| /// these try to take "minimal defaults" that don't assume anything about the runtime they run in. |
| #[derive(Clone, Debug)] |
| pub struct TargetOptions { |
| /// [Data layout](http://llvm.org/docs/LangRef.html#data-layout) to pass to LLVM. |
| pub data_layout: Option<String>, |
| /// Linker to invoke. Defaults to "cc". |
| pub linker: String, |
| /// Archive utility to use when managing archives. Defaults to "ar". |
| pub ar: String, |
| |
| /// Linker arguments that are unconditionally passed *before* any |
| /// user-defined libraries. |
| pub pre_link_args: Vec<String>, |
| /// Objects to link before all others, always found within the |
| /// sysroot folder. |
| pub pre_link_objects_exe: Vec<String>, // ... when linking an executable |
| pub pre_link_objects_dll: Vec<String>, // ... when linking a dylib |
| /// Linker arguments that are unconditionally passed after any |
| /// user-defined but before post_link_objects. Standard platform |
| /// libraries that should be always be linked to, usually go here. |
| pub late_link_args: Vec<String>, |
| /// Objects to link after all others, always found within the |
| /// sysroot folder. |
| pub post_link_objects: Vec<String>, |
| /// Linker arguments that are unconditionally passed *after* any |
| /// user-defined libraries. |
| pub post_link_args: Vec<String>, |
| |
| /// Default CPU to pass to LLVM. Corresponds to `llc -mcpu=$cpu`. Defaults |
| /// to "default". |
| pub cpu: String, |
| /// Default target features to pass to LLVM. These features will *always* be |
| /// passed, and cannot be disabled even via `-C`. Corresponds to `llc |
| /// -mattr=$features`. |
| pub features: String, |
| /// Whether dynamic linking is available on this target. Defaults to false. |
| pub dynamic_linking: bool, |
| /// Whether executables are available on this target. iOS, for example, only allows static |
| /// libraries. Defaults to false. |
| pub executables: bool, |
| /// Relocation model to use in object file. Corresponds to `llc |
| /// -relocation-model=$relocation_model`. Defaults to "pic". |
| pub relocation_model: String, |
| /// Code model to use. Corresponds to `llc -code-model=$code_model`. Defaults to "default". |
| pub code_model: String, |
| /// Do not emit code that uses the "red zone", if the ABI has one. Defaults to false. |
| pub disable_redzone: bool, |
| /// Eliminate frame pointers from stack frames if possible. Defaults to true. |
| pub eliminate_frame_pointer: bool, |
| /// Emit each function in its own section. Defaults to true. |
| pub function_sections: bool, |
| /// String to prepend to the name of every dynamic library. Defaults to "lib". |
| pub dll_prefix: String, |
| /// String to append to the name of every dynamic library. Defaults to ".so". |
| pub dll_suffix: String, |
| /// String to append to the name of every executable. |
| pub exe_suffix: String, |
| /// String to prepend to the name of every static library. Defaults to "lib". |
| pub staticlib_prefix: String, |
| /// String to append to the name of every static library. Defaults to ".a". |
| pub staticlib_suffix: String, |
| /// OS family to use for conditional compilation. Valid options: "unix", "windows". |
| pub target_family: Option<String>, |
| /// Whether the target toolchain is like OSX's. Only useful for compiling against iOS/OS X, in |
| /// particular running dsymutil and some other stuff like `-dead_strip`. Defaults to false. |
| pub is_like_osx: bool, |
| /// Whether the target toolchain is like Windows'. Only useful for compiling against Windows, |
| /// only really used for figuring out how to find libraries, since Windows uses its own |
| /// library naming convention. Defaults to false. |
| pub is_like_windows: bool, |
| pub is_like_msvc: bool, |
| /// Whether the target toolchain is like Android's. Only useful for compiling against Android. |
| /// Defaults to false. |
| pub is_like_android: bool, |
| /// Whether the linker support GNU-like arguments such as -O. Defaults to false. |
| pub linker_is_gnu: bool, |
| /// Whether the linker support rpaths or not. Defaults to false. |
| pub has_rpath: bool, |
| /// Whether to disable linking to compiler-rt. Defaults to false, as LLVM |
| /// will emit references to the functions that compiler-rt provides. |
| pub no_compiler_rt: bool, |
| /// Whether to disable linking to the default libraries, typically corresponds |
| /// to `-nodefaultlibs`. Defaults to true. |
| pub no_default_libraries: bool, |
| /// Dynamically linked executables can be compiled as position independent |
| /// if the default relocation model of position independent code is not |
| /// changed. This is a requirement to take advantage of ASLR, as otherwise |
| /// the functions in the executable are not randomized and can be used |
| /// during an exploit of a vulnerability in any code. |
| pub position_independent_executables: bool, |
| /// Format that archives should be emitted in. This affects whether we use |
| /// LLVM to assemble an archive or fall back to the system linker, and |
| /// currently only "gnu" is used to fall into LLVM. Unknown strings cause |
| /// the system linker to be used. |
| pub archive_format: String, |
| /// Is asm!() allowed? Defaults to true. |
| pub allow_asm: bool, |
| /// Whether the target uses a custom unwind resumption routine. |
| /// By default LLVM lowers `resume` instructions into calls to `_Unwind_Resume` |
| /// defined in libgcc. If this option is enabled, the target must provide |
| /// `eh_unwind_resume` lang item. |
| pub custom_unwind_resume: bool, |
| |
| /// Default crate for allocation symbols to link against |
| pub lib_allocation_crate: String, |
| pub exe_allocation_crate: String, |
| |
| /// Flag indicating whether ELF TLS (e.g. #[thread_local]) is available for |
| /// this target. |
| pub has_elf_tls: bool, |
| } |
| |
| impl Default for TargetOptions { |
| /// Create a set of "sane defaults" for any target. This is still |
| /// incomplete, and if used for compilation, will certainly not work. |
| fn default() -> TargetOptions { |
| TargetOptions { |
| data_layout: None, |
| linker: option_env!("CFG_DEFAULT_LINKER").unwrap_or("cc").to_string(), |
| ar: option_env!("CFG_DEFAULT_AR").unwrap_or("ar").to_string(), |
| pre_link_args: Vec::new(), |
| post_link_args: Vec::new(), |
| cpu: "generic".to_string(), |
| features: "".to_string(), |
| dynamic_linking: false, |
| executables: false, |
| relocation_model: "pic".to_string(), |
| code_model: "default".to_string(), |
| disable_redzone: false, |
| eliminate_frame_pointer: true, |
| function_sections: true, |
| dll_prefix: "lib".to_string(), |
| dll_suffix: ".so".to_string(), |
| exe_suffix: "".to_string(), |
| staticlib_prefix: "lib".to_string(), |
| staticlib_suffix: ".a".to_string(), |
| target_family: None, |
| is_like_osx: false, |
| is_like_windows: false, |
| is_like_android: false, |
| is_like_msvc: false, |
| linker_is_gnu: false, |
| has_rpath: false, |
| no_compiler_rt: false, |
| no_default_libraries: true, |
| position_independent_executables: false, |
| pre_link_objects_exe: Vec::new(), |
| pre_link_objects_dll: Vec::new(), |
| post_link_objects: Vec::new(), |
| late_link_args: Vec::new(), |
| archive_format: String::new(), |
| custom_unwind_resume: false, |
| lib_allocation_crate: "alloc_system".to_string(), |
| exe_allocation_crate: "alloc_system".to_string(), |
| allow_asm: true, |
| has_elf_tls: false, |
| } |
| } |
| } |
| |
| impl Target { |
| /// Given a function ABI, turn "System" into the correct ABI for this target. |
| pub fn adjust_abi(&self, abi: abi::Abi) -> abi::Abi { |
| match abi { |
| abi::System => { |
| if self.options.is_like_windows && self.arch == "x86" { |
| abi::Stdcall |
| } else { |
| abi::C |
| } |
| }, |
| abi => abi |
| } |
| } |
| |
| /// Load a target descriptor from a JSON object. |
| pub fn from_json(obj: Json) -> Target { |
| // this is 1. ugly, 2. error prone. |
| |
| let get_req_field = |name: &str| { |
| match obj.find(name) |
| .map(|s| s.as_string()) |
| .and_then(|os| os.map(|s| s.to_string())) { |
| Some(val) => val, |
| None => { |
| panic!("Field {} in target specification is required", name) |
| } |
| } |
| }; |
| |
| let get_opt_field = |name: &str, default: &str| { |
| obj.find(name).and_then(|s| s.as_string()) |
| .map(|s| s.to_string()) |
| .unwrap_or(default.to_string()) |
| }; |
| |
| let mut base = Target { |
| llvm_target: get_req_field("llvm-target"), |
| target_endian: get_req_field("target-endian"), |
| target_pointer_width: get_req_field("target-pointer-width"), |
| arch: get_req_field("arch"), |
| target_os: get_req_field("os"), |
| target_env: get_opt_field("env", ""), |
| target_vendor: get_opt_field("vendor", "unknown"), |
| options: Default::default(), |
| }; |
| |
| macro_rules! key { |
| ($key_name:ident) => ( { |
| let name = (stringify!($key_name)).replace("_", "-"); |
| obj.find(&name[..]).map(|o| o.as_string() |
| .map(|s| base.options.$key_name = s.to_string())); |
| } ); |
| ($key_name:ident, bool) => ( { |
| let name = (stringify!($key_name)).replace("_", "-"); |
| obj.find(&name[..]) |
| .map(|o| o.as_boolean() |
| .map(|s| base.options.$key_name = s)); |
| } ); |
| ($key_name:ident, list) => ( { |
| let name = (stringify!($key_name)).replace("_", "-"); |
| obj.find(&name[..]).map(|o| o.as_array() |
| .map(|v| base.options.$key_name = v.iter() |
| .map(|a| a.as_string().unwrap().to_string()).collect() |
| ) |
| ); |
| } ); |
| ($key_name:ident, optional) => ( { |
| let name = (stringify!($key_name)).replace("_", "-"); |
| if let Some(o) = obj.find(&name[..]) { |
| base.options.$key_name = o |
| .as_string() |
| .map(|s| s.to_string() ); |
| } |
| } ); |
| } |
| |
| key!(cpu); |
| key!(ar); |
| key!(linker); |
| key!(relocation_model); |
| key!(code_model); |
| key!(dll_prefix); |
| key!(dll_suffix); |
| key!(exe_suffix); |
| key!(staticlib_prefix); |
| key!(staticlib_suffix); |
| key!(features); |
| key!(data_layout, optional); |
| key!(dynamic_linking, bool); |
| key!(executables, bool); |
| key!(disable_redzone, bool); |
| key!(eliminate_frame_pointer, bool); |
| key!(function_sections, bool); |
| key!(target_family, optional); |
| key!(is_like_osx, bool); |
| key!(is_like_windows, bool); |
| key!(linker_is_gnu, bool); |
| key!(has_rpath, bool); |
| key!(no_compiler_rt, bool); |
| key!(no_default_libraries, bool); |
| key!(pre_link_args, list); |
| key!(post_link_args, list); |
| key!(archive_format); |
| key!(allow_asm, bool); |
| key!(custom_unwind_resume, bool); |
| |
| base |
| } |
| |
| /// Search RUST_TARGET_PATH for a JSON file specifying the given target |
| /// triple. Note that it could also just be a bare filename already, so also |
| /// check for that. If one of the hardcoded targets we know about, just |
| /// return it directly. |
| /// |
| /// The error string could come from any of the APIs called, including |
| /// filesystem access and JSON decoding. |
| pub fn search(target: &str) -> Result<Target, String> { |
| use std::env; |
| use std::ffi::OsString; |
| use std::fs::File; |
| use std::path::{Path, PathBuf}; |
| use serialize::json; |
| |
| fn load_file(path: &Path) -> Result<Target, String> { |
| let mut f = try!(File::open(path).map_err(|e| e.to_string())); |
| let mut contents = Vec::new(); |
| try!(f.read_to_end(&mut contents).map_err(|e| e.to_string())); |
| let obj = try!(json::from_reader(&mut &contents[..]) |
| .map_err(|e| e.to_string())); |
| Ok(Target::from_json(obj)) |
| } |
| |
| // this would use a match if stringify! were allowed in pattern position |
| macro_rules! load_specific { |
| ( $($name:ident),+ ) => ( |
| { |
| $(mod $name;)* |
| let target = target.replace("-", "_"); |
| if false { } |
| $( |
| else if target == stringify!($name) { |
| let t = $name::target(); |
| debug!("Got builtin target: {:?}", t); |
| return Ok(t); |
| } |
| )* |
| else if target == "x86_64-w64-mingw32" { |
| let t = x86_64_pc_windows_gnu::target(); |
| return Ok(t); |
| } else if target == "i686-w64-mingw32" { |
| let t = i686_pc_windows_gnu::target(); |
| return Ok(t); |
| } |
| } |
| ) |
| } |
| |
| load_specific!( |
| x86_64_unknown_linux_gnu, |
| i686_unknown_linux_gnu, |
| mips_unknown_linux_gnu, |
| mipsel_unknown_linux_gnu, |
| powerpc_unknown_linux_gnu, |
| powerpc64_unknown_linux_gnu, |
| powerpc64le_unknown_linux_gnu, |
| arm_unknown_linux_gnueabi, |
| arm_unknown_linux_gnueabihf, |
| aarch64_unknown_linux_gnu, |
| x86_64_unknown_linux_musl, |
| |
| i686_linux_android, |
| arm_linux_androideabi, |
| aarch64_linux_android, |
| |
| i686_unknown_freebsd, |
| x86_64_unknown_freebsd, |
| |
| i686_unknown_dragonfly, |
| x86_64_unknown_dragonfly, |
| |
| x86_64_unknown_bitrig, |
| x86_64_unknown_openbsd, |
| x86_64_unknown_netbsd, |
| x86_64_rumprun_netbsd, |
| |
| x86_64_apple_darwin, |
| i686_apple_darwin, |
| |
| i386_apple_ios, |
| x86_64_apple_ios, |
| aarch64_apple_ios, |
| armv7_apple_ios, |
| armv7s_apple_ios, |
| |
| x86_64_pc_windows_gnu, |
| i686_pc_windows_gnu, |
| |
| x86_64_pc_windows_msvc, |
| i686_pc_windows_msvc, |
| |
| le32_unknown_nacl |
| ); |
| |
| |
| let path = Path::new(target); |
| |
| if path.is_file() { |
| return load_file(&path); |
| } |
| |
| let path = { |
| let mut target = target.to_string(); |
| target.push_str(".json"); |
| PathBuf::from(target) |
| }; |
| |
| let target_path = env::var_os("RUST_TARGET_PATH") |
| .unwrap_or(OsString::new()); |
| |
| // FIXME 16351: add a sane default search path? |
| |
| for dir in env::split_paths(&target_path) { |
| let p = dir.join(&path); |
| if p.is_file() { |
| return load_file(&p); |
| } |
| } |
| |
| Err(format!("Could not find specification for target {:?}", target)) |
| } |
| } |
| |
| fn maybe_jemalloc() -> String { |
| if cfg!(disable_jemalloc) { |
| "alloc_system".to_string() |
| } else { |
| "alloc_jemalloc".to_string() |
| } |
| } |