1 // Copyright 2014-2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 //! [Flexible target specification.](https://github.com/rust-lang/rfcs/pull/131)
13 //! Rust targets a wide variety of usecases, and in the interest of flexibility,
14 //! allows new target triples to be defined in configuration files. Most users
15 //! will not need to care about these, but this is invaluable when porting Rust
16 //! to a new platform, and allows for an unprecedented level of control over how
17 //! the compiler works.
19 //! # Using custom targets
21 //! A target triple, as passed via `rustc --target=TRIPLE`, will first be
22 //! compared against the list of built-in targets. This is to ease distributing
23 //! rustc (no need for configuration files) and also to hold these built-in
24 //! targets as immutable and sacred. If `TRIPLE` is not one of the built-in
25 //! targets, rustc will check if a file named `TRIPLE` exists. If it does, it
26 //! will be loaded as the target configuration. If the file does not exist,
27 //! rustc will search each directory in the environment variable
28 //! `RUST_TARGET_PATH` for a file named `TRIPLE.json`. The first one found will
29 //! be loaded. If no file is found in any of those directories, a fatal error
32 //! Projects defining their own targets should use
33 //! `--target=path/to/my-awesome-platform.json` instead of adding to
34 //! `RUST_TARGET_PATH`.
36 //! # Defining a new target
38 //! Targets are defined using [JSON](http://json.org/). The `Target` struct in
39 //! this module defines the format the JSON file should take, though each
40 //! underscore in the field names should be replaced with a hyphen (`-`) in the
41 //! JSON file. Some fields are required in every target specification, such as
42 //! `llvm-target`, `target-endian`, `target-pointer-width`, `data-layout`,
43 //! `arch`, and `os`. In general, options passed to rustc with `-C` override
44 //! the target's settings, though `target-feature` and `link-args` will *add*
45 //! to the list specified by the target, rather than replace.
47 use serialize::json::{Json, ToJson};
48 use std::collections::BTreeMap;
49 use std::default::Default;
50 use std::io::prelude::*;
51 use syntax::abi::{Abi, lookup as lookup_abi};
53 use {LinkerFlavor, PanicStrategy};
70 mod windows_msvc_base;
75 pub type LinkArgs = BTreeMap<LinkerFlavor, Vec<String>>;
76 pub type TargetResult = Result<Target, String>;
78 macro_rules! supported_targets {
79 ( $(($triple:expr, $module:ident),)+ ) => (
82 /// List of supported targets
83 const TARGETS: &'static [&'static str] = &[$($triple),*];
85 fn load_specific(target: &str) -> TargetResult {
89 let mut t = $module::target()?;
90 t.options.is_builtin = true;
92 // round-trip through the JSON parser to ensure at
93 // run-time that the parser works correctly
94 t = Target::from_json(t.to_json())?;
95 debug!("Got builtin target: {:?}", t);
99 _ => Err(format!("Unable to find target: {}", target))
103 pub fn get_targets() -> Box<Iterator<Item=String>> {
104 Box::new(TARGETS.iter().filter_map(|t| -> Option<String> {
106 .and(Ok(t.to_string()))
112 mod test_json_encode_decode {
113 use serialize::json::ToJson;
115 $(use super::$module;)*
120 // Grab the TargetResult struct. If we successfully retrieved
121 // a Target, then the test JSON encoding/decoding can run for this
122 // Target on this testing platform (i.e., checking the iOS targets
123 // only on a Mac test platform).
124 let _ = $module::target().map(|original| {
125 let as_json = original.to_json();
126 let parsed = Target::from_json(as_json).unwrap();
127 assert_eq!(original, parsed);
136 ("x86_64-unknown-linux-gnu", x86_64_unknown_linux_gnu),
137 ("i686-unknown-linux-gnu", i686_unknown_linux_gnu),
138 ("i586-unknown-linux-gnu", i586_unknown_linux_gnu),
139 ("mips-unknown-linux-gnu", mips_unknown_linux_gnu),
140 ("mips64-unknown-linux-gnuabi64", mips64_unknown_linux_gnuabi64),
141 ("mips64el-unknown-linux-gnuabi64", mips64el_unknown_linux_gnuabi64),
142 ("mipsel-unknown-linux-gnu", mipsel_unknown_linux_gnu),
143 ("powerpc-unknown-linux-gnu", powerpc_unknown_linux_gnu),
144 ("powerpc64-unknown-linux-gnu", powerpc64_unknown_linux_gnu),
145 ("powerpc64le-unknown-linux-gnu", powerpc64le_unknown_linux_gnu),
146 ("s390x-unknown-linux-gnu", s390x_unknown_linux_gnu),
147 ("arm-unknown-linux-gnueabi", arm_unknown_linux_gnueabi),
148 ("arm-unknown-linux-gnueabihf", arm_unknown_linux_gnueabihf),
149 ("arm-unknown-linux-musleabi", arm_unknown_linux_musleabi),
150 ("arm-unknown-linux-musleabihf", arm_unknown_linux_musleabihf),
151 ("armv5te-unknown-linux-gnueabi", armv5te_unknown_linux_gnueabi),
152 ("armv7-unknown-linux-gnueabihf", armv7_unknown_linux_gnueabihf),
153 ("armv7-unknown-linux-musleabihf", armv7_unknown_linux_musleabihf),
154 ("aarch64-unknown-linux-gnu", aarch64_unknown_linux_gnu),
155 ("x86_64-unknown-linux-musl", x86_64_unknown_linux_musl),
156 ("i686-unknown-linux-musl", i686_unknown_linux_musl),
157 ("mips-unknown-linux-musl", mips_unknown_linux_musl),
158 ("mipsel-unknown-linux-musl", mipsel_unknown_linux_musl),
159 ("mips-unknown-linux-uclibc", mips_unknown_linux_uclibc),
160 ("mipsel-unknown-linux-uclibc", mipsel_unknown_linux_uclibc),
162 ("sparc64-unknown-linux-gnu", sparc64_unknown_linux_gnu),
164 ("i686-linux-android", i686_linux_android),
165 ("arm-linux-androideabi", arm_linux_androideabi),
166 ("armv7-linux-androideabi", armv7_linux_androideabi),
167 ("aarch64-linux-android", aarch64_linux_android),
169 ("aarch64-unknown-freebsd", aarch64_unknown_freebsd),
170 ("i686-unknown-freebsd", i686_unknown_freebsd),
171 ("x86_64-unknown-freebsd", x86_64_unknown_freebsd),
173 ("i686-unknown-dragonfly", i686_unknown_dragonfly),
174 ("x86_64-unknown-dragonfly", x86_64_unknown_dragonfly),
176 ("x86_64-unknown-bitrig", x86_64_unknown_bitrig),
178 ("i686-unknown-openbsd", i686_unknown_openbsd),
179 ("x86_64-unknown-openbsd", x86_64_unknown_openbsd),
181 ("i686-unknown-netbsd", i686_unknown_netbsd),
182 ("sparc64-unknown-netbsd", sparc64_unknown_netbsd),
183 ("x86_64-unknown-netbsd", x86_64_unknown_netbsd),
184 ("x86_64-rumprun-netbsd", x86_64_rumprun_netbsd),
186 ("i686-unknown-haiku", i686_unknown_haiku),
187 ("x86_64-unknown-haiku", x86_64_unknown_haiku),
189 ("x86_64-apple-darwin", x86_64_apple_darwin),
190 ("i686-apple-darwin", i686_apple_darwin),
192 ("aarch64-unknown-fuchsia", aarch64_unknown_fuchsia),
193 ("x86_64-unknown-fuchsia", x86_64_unknown_fuchsia),
195 ("x86_64-unknown-redox", x86_64_unknown_redox),
197 ("i386-apple-ios", i386_apple_ios),
198 ("x86_64-apple-ios", x86_64_apple_ios),
199 ("aarch64-apple-ios", aarch64_apple_ios),
200 ("armv7-apple-ios", armv7_apple_ios),
201 ("armv7s-apple-ios", armv7s_apple_ios),
203 ("x86_64-sun-solaris", x86_64_sun_solaris),
204 ("sparcv9-sun-solaris", sparcv9_sun_solaris),
206 ("x86_64-pc-windows-gnu", x86_64_pc_windows_gnu),
207 ("i686-pc-windows-gnu", i686_pc_windows_gnu),
209 ("x86_64-pc-windows-msvc", x86_64_pc_windows_msvc),
210 ("i686-pc-windows-msvc", i686_pc_windows_msvc),
211 ("i586-pc-windows-msvc", i586_pc_windows_msvc),
213 ("le32-unknown-nacl", le32_unknown_nacl),
214 ("asmjs-unknown-emscripten", asmjs_unknown_emscripten),
215 ("wasm32-unknown-emscripten", wasm32_unknown_emscripten),
217 ("thumbv6m-none-eabi", thumbv6m_none_eabi),
218 ("thumbv7m-none-eabi", thumbv7m_none_eabi),
219 ("thumbv7em-none-eabi", thumbv7em_none_eabi),
220 ("thumbv7em-none-eabihf", thumbv7em_none_eabihf),
223 /// Everything `rustc` knows about how to compile for a specific target.
225 /// Every field here must be specified, and has no default value.
226 #[derive(PartialEq, Clone, Debug)]
228 /// Target triple to pass to LLVM.
229 pub llvm_target: String,
230 /// String to use as the `target_endian` `cfg` variable.
231 pub target_endian: String,
232 /// String to use as the `target_pointer_width` `cfg` variable.
233 pub target_pointer_width: String,
234 /// OS name to use for conditional compilation.
235 pub target_os: String,
236 /// Environment name to use for conditional compilation.
237 pub target_env: String,
238 /// Vendor name to use for conditional compilation.
239 pub target_vendor: String,
240 /// Architecture to use for ABI considerations. Valid options: "x86",
241 /// "x86_64", "arm", "aarch64", "mips", "powerpc", and "powerpc64".
243 /// [Data layout](http://llvm.org/docs/LangRef.html#data-layout) to pass to LLVM.
244 pub data_layout: String,
246 pub linker_flavor: LinkerFlavor,
247 /// Optional settings with defaults.
248 pub options: TargetOptions,
251 /// Optional aspects of a target specification.
253 /// This has an implementation of `Default`, see each field for what the default is. In general,
254 /// these try to take "minimal defaults" that don't assume anything about the runtime they run in.
255 #[derive(PartialEq, Clone, Debug)]
256 pub struct TargetOptions {
257 /// Whether the target is built-in or loaded from a custom target specification.
258 pub is_builtin: bool,
260 /// Linker to invoke. Defaults to "cc".
262 /// Archive utility to use when managing archives. Defaults to "ar".
265 /// Linker arguments that are unconditionally passed *before* any
266 /// user-defined libraries.
267 pub pre_link_args: LinkArgs,
268 /// Objects to link before all others, always found within the
270 pub pre_link_objects_exe: Vec<String>, // ... when linking an executable
271 pub pre_link_objects_dll: Vec<String>, // ... when linking a dylib
272 /// Linker arguments that are unconditionally passed after any
273 /// user-defined but before post_link_objects. Standard platform
274 /// libraries that should be always be linked to, usually go here.
275 pub late_link_args: LinkArgs,
276 /// Objects to link after all others, always found within the
278 pub post_link_objects: Vec<String>,
279 /// Linker arguments that are unconditionally passed *after* any
280 /// user-defined libraries.
281 pub post_link_args: LinkArgs,
283 /// Extra arguments to pass to the external assembler (when used)
284 pub asm_args: Vec<String>,
286 /// Default CPU to pass to LLVM. Corresponds to `llc -mcpu=$cpu`. Defaults
289 /// Default target features to pass to LLVM. These features will *always* be
290 /// passed, and cannot be disabled even via `-C`. Corresponds to `llc
291 /// -mattr=$features`.
292 pub features: String,
293 /// Whether dynamic linking is available on this target. Defaults to false.
294 pub dynamic_linking: bool,
295 /// Whether executables are available on this target. iOS, for example, only allows static
296 /// libraries. Defaults to false.
297 pub executables: bool,
298 /// Relocation model to use in object file. Corresponds to `llc
299 /// -relocation-model=$relocation_model`. Defaults to "pic".
300 pub relocation_model: String,
301 /// Code model to use. Corresponds to `llc -code-model=$code_model`. Defaults to "default".
302 pub code_model: String,
303 /// Do not emit code that uses the "red zone", if the ABI has one. Defaults to false.
304 pub disable_redzone: bool,
305 /// Eliminate frame pointers from stack frames if possible. Defaults to true.
306 pub eliminate_frame_pointer: bool,
307 /// Emit each function in its own section. Defaults to true.
308 pub function_sections: bool,
309 /// String to prepend to the name of every dynamic library. Defaults to "lib".
310 pub dll_prefix: String,
311 /// String to append to the name of every dynamic library. Defaults to ".so".
312 pub dll_suffix: String,
313 /// String to append to the name of every executable.
314 pub exe_suffix: String,
315 /// String to prepend to the name of every static library. Defaults to "lib".
316 pub staticlib_prefix: String,
317 /// String to append to the name of every static library. Defaults to ".a".
318 pub staticlib_suffix: String,
319 /// OS family to use for conditional compilation. Valid options: "unix", "windows".
320 pub target_family: Option<String>,
321 /// Whether the target toolchain is like OpenBSD's.
322 /// Only useful for compiling against OpenBSD, for configuring abi when returning a struct.
323 pub is_like_openbsd: bool,
324 /// Whether the target toolchain is like macOS's. Only useful for compiling against iOS/macOS,
325 /// in particular running dsymutil and some other stuff like `-dead_strip`. Defaults to false.
326 pub is_like_osx: bool,
327 /// Whether the target toolchain is like Solaris's.
328 /// Only useful for compiling against Illumos/Solaris,
329 /// as they have a different set of linker flags. Defaults to false.
330 pub is_like_solaris: bool,
331 /// Whether the target toolchain is like Windows'. Only useful for compiling against Windows,
332 /// only really used for figuring out how to find libraries, since Windows uses its own
333 /// library naming convention. Defaults to false.
334 pub is_like_windows: bool,
335 pub is_like_msvc: bool,
336 /// Whether the target toolchain is like Android's. Only useful for compiling against Android.
337 /// Defaults to false.
338 pub is_like_android: bool,
339 /// Whether the target toolchain is like Emscripten's. Only useful for compiling with
340 /// Emscripten toolchain.
341 /// Defaults to false.
342 pub is_like_emscripten: bool,
343 /// Whether the linker support GNU-like arguments such as -O. Defaults to false.
344 pub linker_is_gnu: bool,
345 /// The MinGW toolchain has a known issue that prevents it from correctly
346 /// handling COFF object files with more than 2^15 sections. Since each weak
347 /// symbol needs its own COMDAT section, weak linkage implies a large
348 /// number sections that easily exceeds the given limit for larger
349 /// codebases. Consequently we want a way to disallow weak linkage on some
351 pub allows_weak_linkage: bool,
352 /// Whether the linker support rpaths or not. Defaults to false.
354 /// Whether to disable linking to the default libraries, typically corresponds
355 /// to `-nodefaultlibs`. Defaults to true.
356 pub no_default_libraries: bool,
357 /// Dynamically linked executables can be compiled as position independent
358 /// if the default relocation model of position independent code is not
359 /// changed. This is a requirement to take advantage of ASLR, as otherwise
360 /// the functions in the executable are not randomized and can be used
361 /// during an exploit of a vulnerability in any code.
362 pub position_independent_executables: bool,
363 /// Format that archives should be emitted in. This affects whether we use
364 /// LLVM to assemble an archive or fall back to the system linker, and
365 /// currently only "gnu" is used to fall into LLVM. Unknown strings cause
366 /// the system linker to be used.
367 pub archive_format: String,
368 /// Is asm!() allowed? Defaults to true.
370 /// Whether the target uses a custom unwind resumption routine.
371 /// By default LLVM lowers `resume` instructions into calls to `_Unwind_Resume`
372 /// defined in libgcc. If this option is enabled, the target must provide
373 /// `eh_unwind_resume` lang item.
374 pub custom_unwind_resume: bool,
376 /// Default crate for allocation symbols to link against
377 pub lib_allocation_crate: String,
378 pub exe_allocation_crate: String,
380 /// Flag indicating whether ELF TLS (e.g. #[thread_local]) is available for
382 pub has_elf_tls: bool,
383 // This is mainly for easy compatibility with emscripten.
384 // If we give emcc .o files that are actually .bc files it
386 pub obj_is_bitcode: bool,
388 // LLVM can't produce object files for this target. Instead, we'll make LLVM
389 // emit assembly and then use `gcc` to turn that assembly into an object
391 pub no_integrated_as: bool,
393 /// Don't use this field; instead use the `.min_atomic_width()` method.
394 pub min_atomic_width: Option<u64>,
396 /// Don't use this field; instead use the `.max_atomic_width()` method.
397 pub max_atomic_width: Option<u64>,
399 /// Panic strategy: "unwind" or "abort"
400 pub panic_strategy: PanicStrategy,
402 /// A blacklist of ABIs unsupported by the current target. Note that generic
403 /// ABIs are considered to be supported on all platforms and cannot be blacklisted.
404 pub abi_blacklist: Vec<Abi>,
406 /// Whether or not the CRT is statically linked by default.
407 pub crt_static_default: bool,
410 impl Default for TargetOptions {
411 /// Create a set of "sane defaults" for any target. This is still
412 /// incomplete, and if used for compilation, will certainly not work.
413 fn default() -> TargetOptions {
416 linker: option_env!("CFG_DEFAULT_LINKER").unwrap_or("cc").to_string(),
417 ar: option_env!("CFG_DEFAULT_AR").unwrap_or("ar").to_string(),
418 pre_link_args: LinkArgs::new(),
419 post_link_args: LinkArgs::new(),
420 asm_args: Vec::new(),
421 cpu: "generic".to_string(),
422 features: "".to_string(),
423 dynamic_linking: false,
425 relocation_model: "pic".to_string(),
426 code_model: "default".to_string(),
427 disable_redzone: false,
428 eliminate_frame_pointer: true,
429 function_sections: true,
430 dll_prefix: "lib".to_string(),
431 dll_suffix: ".so".to_string(),
432 exe_suffix: "".to_string(),
433 staticlib_prefix: "lib".to_string(),
434 staticlib_suffix: ".a".to_string(),
436 is_like_openbsd: false,
438 is_like_solaris: false,
439 is_like_windows: false,
440 is_like_android: false,
441 is_like_emscripten: false,
443 linker_is_gnu: false,
444 allows_weak_linkage: true,
446 no_default_libraries: true,
447 position_independent_executables: false,
448 pre_link_objects_exe: Vec::new(),
449 pre_link_objects_dll: Vec::new(),
450 post_link_objects: Vec::new(),
451 late_link_args: LinkArgs::new(),
452 archive_format: "gnu".to_string(),
453 custom_unwind_resume: false,
454 lib_allocation_crate: "alloc_system".to_string(),
455 exe_allocation_crate: "alloc_system".to_string(),
458 obj_is_bitcode: false,
459 no_integrated_as: false,
460 min_atomic_width: None,
461 max_atomic_width: None,
462 panic_strategy: PanicStrategy::Unwind,
463 abi_blacklist: vec![],
464 crt_static_default: false,
470 /// Given a function ABI, turn "System" into the correct ABI for this target.
471 pub fn adjust_abi(&self, abi: Abi) -> Abi {
474 if self.options.is_like_windows && self.arch == "x86" {
484 /// Minimum integer size in bits that this target can perform atomic
486 pub fn min_atomic_width(&self) -> u64 {
487 self.options.min_atomic_width.unwrap_or(8)
490 /// Maximum integer size in bits that this target can perform atomic
492 pub fn max_atomic_width(&self) -> u64 {
493 self.options.max_atomic_width.unwrap_or(self.target_pointer_width.parse().unwrap())
496 pub fn is_abi_supported(&self, abi: Abi) -> bool {
497 abi.generic() || !self.options.abi_blacklist.contains(&abi)
500 /// Load a target descriptor from a JSON object.
501 pub fn from_json(obj: Json) -> TargetResult {
502 // While ugly, this code must remain this way to retain
503 // compatibility with existing JSON fields and the internal
504 // expected naming of the Target and TargetOptions structs.
505 // To ensure compatibility is retained, the built-in targets
506 // are round-tripped through this code to catch cases where
507 // the JSON parser is not updated to match the structs.
509 let get_req_field = |name: &str| {
511 .map(|s| s.as_string())
512 .and_then(|os| os.map(|s| s.to_string())) {
513 Some(val) => Ok(val),
515 return Err(format!("Field {} in target specification is required", name))
520 let get_opt_field = |name: &str, default: &str| {
521 obj.find(name).and_then(|s| s.as_string())
522 .map(|s| s.to_string())
523 .unwrap_or(default.to_string())
526 let mut base = Target {
527 llvm_target: get_req_field("llvm-target")?,
528 target_endian: get_req_field("target-endian")?,
529 target_pointer_width: get_req_field("target-pointer-width")?,
530 data_layout: get_req_field("data-layout")?,
531 arch: get_req_field("arch")?,
532 target_os: get_req_field("os")?,
533 target_env: get_opt_field("env", ""),
534 target_vendor: get_opt_field("vendor", "unknown"),
535 linker_flavor: LinkerFlavor::from_str(&*get_req_field("linker-flavor")?)
537 format!("linker flavor must be {}", LinkerFlavor::one_of())
539 options: Default::default(),
543 ($key_name:ident) => ( {
544 let name = (stringify!($key_name)).replace("_", "-");
545 obj.find(&name[..]).map(|o| o.as_string()
546 .map(|s| base.options.$key_name = s.to_string()));
548 ($key_name:ident, bool) => ( {
549 let name = (stringify!($key_name)).replace("_", "-");
551 .map(|o| o.as_boolean()
552 .map(|s| base.options.$key_name = s));
554 ($key_name:ident, Option<u64>) => ( {
555 let name = (stringify!($key_name)).replace("_", "-");
558 .map(|s| base.options.$key_name = Some(s)));
560 ($key_name:ident, PanicStrategy) => ( {
561 let name = (stringify!($key_name)).replace("_", "-");
562 obj.find(&name[..]).and_then(|o| o.as_string().and_then(|s| {
564 "unwind" => base.options.$key_name = PanicStrategy::Unwind,
565 "abort" => base.options.$key_name = PanicStrategy::Abort,
566 _ => return Some(Err(format!("'{}' is not a valid value for \
567 panic-strategy. Use 'unwind' or 'abort'.",
571 })).unwrap_or(Ok(()))
573 ($key_name:ident, list) => ( {
574 let name = (stringify!($key_name)).replace("_", "-");
575 obj.find(&name[..]).map(|o| o.as_array()
576 .map(|v| base.options.$key_name = v.iter()
577 .map(|a| a.as_string().unwrap().to_string()).collect()
581 ($key_name:ident, optional) => ( {
582 let name = (stringify!($key_name)).replace("_", "-");
583 if let Some(o) = obj.find(&name[..]) {
584 base.options.$key_name = o
586 .map(|s| s.to_string() );
589 ($key_name:ident, LinkerFlavor) => ( {
590 let name = (stringify!($key_name)).replace("_", "-");
591 obj.find(&name[..]).and_then(|o| o.as_string().map(|s| {
592 LinkerFlavor::from_str(&s).ok_or_else(|| {
593 Err(format!("'{}' is not a valid value for linker-flavor. \
594 Use 'em', 'gcc', 'ld' or 'msvc.", s))
596 })).unwrap_or(Ok(()))
598 ($key_name:ident, link_args) => ( {
599 let name = (stringify!($key_name)).replace("_", "-");
600 if let Some(obj) = obj.find(&name[..]).and_then(|o| o.as_object()) {
601 let mut args = LinkArgs::new();
603 let k = LinkerFlavor::from_str(&k).ok_or_else(|| {
604 format!("{}: '{}' is not a valid value for linker-flavor. \
605 Use 'em', 'gcc', 'ld' or 'msvc'", name, k)
608 let v = v.as_array().map(|a| {
611 .filter_map(|o| o.as_string())
612 .map(|s| s.to_owned())
614 }).unwrap_or(vec![]);
618 base.options.$key_name = args;
623 key!(is_builtin, bool);
626 key!(pre_link_args, link_args);
627 key!(pre_link_objects_exe, list);
628 key!(pre_link_objects_dll, list);
629 key!(late_link_args, link_args);
630 key!(post_link_objects, list);
631 key!(post_link_args, link_args);
632 key!(asm_args, list);
635 key!(dynamic_linking, bool);
636 key!(executables, bool);
637 key!(relocation_model);
639 key!(disable_redzone, bool);
640 key!(eliminate_frame_pointer, bool);
641 key!(function_sections, bool);
645 key!(staticlib_prefix);
646 key!(staticlib_suffix);
647 key!(target_family, optional);
648 key!(is_like_openbsd, bool);
649 key!(is_like_osx, bool);
650 key!(is_like_solaris, bool);
651 key!(is_like_windows, bool);
652 key!(is_like_msvc, bool);
653 key!(is_like_emscripten, bool);
654 key!(is_like_android, bool);
655 key!(linker_is_gnu, bool);
656 key!(allows_weak_linkage, bool);
657 key!(has_rpath, bool);
658 key!(no_default_libraries, bool);
659 key!(position_independent_executables, bool);
660 key!(archive_format);
661 key!(allow_asm, bool);
662 key!(custom_unwind_resume, bool);
663 key!(lib_allocation_crate);
664 key!(exe_allocation_crate);
665 key!(has_elf_tls, bool);
666 key!(obj_is_bitcode, bool);
667 key!(no_integrated_as, bool);
668 key!(max_atomic_width, Option<u64>);
669 key!(min_atomic_width, Option<u64>);
670 try!(key!(panic_strategy, PanicStrategy));
671 key!(crt_static_default, bool);
673 if let Some(array) = obj.find("abi-blacklist").and_then(Json::as_array) {
674 for name in array.iter().filter_map(|abi| abi.as_string()) {
675 match lookup_abi(name) {
678 return Err(format!("The ABI \"{}\" is considered to be supported on \
679 all targets and cannot be blacklisted", abi))
682 base.options.abi_blacklist.push(abi)
684 None => return Err(format!("Unknown ABI \"{}\" in target specification", name))
692 /// Search RUST_TARGET_PATH for a JSON file specifying the given target
693 /// triple. Note that it could also just be a bare filename already, so also
694 /// check for that. If one of the hardcoded targets we know about, just
695 /// return it directly.
697 /// The error string could come from any of the APIs called, including
698 /// filesystem access and JSON decoding.
699 pub fn search(target: &str) -> Result<Target, String> {
701 use std::ffi::OsString;
703 use std::path::{Path, PathBuf};
706 fn load_file(path: &Path) -> Result<Target, String> {
707 let mut f = File::open(path).map_err(|e| e.to_string())?;
708 let mut contents = Vec::new();
709 f.read_to_end(&mut contents).map_err(|e| e.to_string())?;
710 let obj = json::from_reader(&mut &contents[..])
711 .map_err(|e| e.to_string())?;
712 Target::from_json(obj)
715 if let Ok(t) = load_specific(target) {
719 let path = Path::new(target);
722 return load_file(&path);
726 let mut target = target.to_string();
727 target.push_str(".json");
728 PathBuf::from(target)
731 let target_path = env::var_os("RUST_TARGET_PATH")
732 .unwrap_or(OsString::new());
734 // FIXME 16351: add a sane default search path?
736 for dir in env::split_paths(&target_path) {
737 let p = dir.join(&path);
739 return load_file(&p);
743 Err(format!("Could not find specification for target {:?}", target))
747 impl ToJson for Target {
748 fn to_json(&self) -> Json {
749 let mut d = BTreeMap::new();
750 let default: TargetOptions = Default::default();
752 macro_rules! target_val {
754 let name = (stringify!($attr)).replace("_", "-");
755 d.insert(name.to_string(), self.$attr.to_json());
757 ($attr:ident, $key_name:expr) => ( {
758 let name = $key_name;
759 d.insert(name.to_string(), self.$attr.to_json());
763 macro_rules! target_option_val {
765 let name = (stringify!($attr)).replace("_", "-");
766 if default.$attr != self.options.$attr {
767 d.insert(name.to_string(), self.options.$attr.to_json());
770 ($attr:ident, $key_name:expr) => ( {
771 let name = $key_name;
772 if default.$attr != self.options.$attr {
773 d.insert(name.to_string(), self.options.$attr.to_json());
776 (link_args - $attr:ident) => ( {
777 let name = (stringify!($attr)).replace("_", "-");
778 if default.$attr != self.options.$attr {
779 let obj = self.options.$attr
781 .map(|(k, v)| (k.desc().to_owned(), v.clone()))
782 .collect::<BTreeMap<_, _>>();
783 d.insert(name.to_string(), obj.to_json());
788 target_val!(llvm_target);
789 target_val!(target_endian);
790 target_val!(target_pointer_width);
792 target_val!(target_os, "os");
793 target_val!(target_env, "env");
794 target_val!(target_vendor, "vendor");
795 target_val!(data_layout);
796 target_val!(linker_flavor);
798 target_option_val!(is_builtin);
799 target_option_val!(linker);
800 target_option_val!(ar);
801 target_option_val!(link_args - pre_link_args);
802 target_option_val!(pre_link_objects_exe);
803 target_option_val!(pre_link_objects_dll);
804 target_option_val!(link_args - late_link_args);
805 target_option_val!(post_link_objects);
806 target_option_val!(link_args - post_link_args);
807 target_option_val!(asm_args);
808 target_option_val!(cpu);
809 target_option_val!(features);
810 target_option_val!(dynamic_linking);
811 target_option_val!(executables);
812 target_option_val!(relocation_model);
813 target_option_val!(code_model);
814 target_option_val!(disable_redzone);
815 target_option_val!(eliminate_frame_pointer);
816 target_option_val!(function_sections);
817 target_option_val!(dll_prefix);
818 target_option_val!(dll_suffix);
819 target_option_val!(exe_suffix);
820 target_option_val!(staticlib_prefix);
821 target_option_val!(staticlib_suffix);
822 target_option_val!(target_family);
823 target_option_val!(is_like_openbsd);
824 target_option_val!(is_like_osx);
825 target_option_val!(is_like_solaris);
826 target_option_val!(is_like_windows);
827 target_option_val!(is_like_msvc);
828 target_option_val!(is_like_emscripten);
829 target_option_val!(is_like_android);
830 target_option_val!(linker_is_gnu);
831 target_option_val!(allows_weak_linkage);
832 target_option_val!(has_rpath);
833 target_option_val!(no_default_libraries);
834 target_option_val!(position_independent_executables);
835 target_option_val!(archive_format);
836 target_option_val!(allow_asm);
837 target_option_val!(custom_unwind_resume);
838 target_option_val!(lib_allocation_crate);
839 target_option_val!(exe_allocation_crate);
840 target_option_val!(has_elf_tls);
841 target_option_val!(obj_is_bitcode);
842 target_option_val!(no_integrated_as);
843 target_option_val!(min_atomic_width);
844 target_option_val!(max_atomic_width);
845 target_option_val!(panic_strategy);
846 target_option_val!(crt_static_default);
848 if default.abi_blacklist != self.options.abi_blacklist {
849 d.insert("abi-blacklist".to_string(), self.options.abi_blacklist.iter()
850 .map(Abi::name).map(|name| name.to_json())
851 .collect::<Vec<_>>().to_json());
858 fn maybe_jemalloc() -> String {
859 if cfg!(feature = "jemalloc") {
860 "alloc_jemalloc".to_string()
862 "alloc_system".to_string()