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;
51 use std::path::{Path, PathBuf};
52 use std::str::FromStr;
53 use spec::abi::{Abi, lookup as lookup_abi};
72 mod windows_msvc_base;
78 #[derive(Clone, Copy, Debug, Eq, Ord, PartialEq, PartialOrd, Hash,
79 RustcEncodable, RustcDecodable)]
80 pub enum LinkerFlavor {
88 #[derive(Clone, Copy, Debug, Eq, Ord, PartialEq, PartialOrd, Hash,
89 RustcEncodable, RustcDecodable)]
97 impl ToJson for LinkerFlavor {
98 fn to_json(&self) -> Json {
102 macro_rules! flavor_mappings {
103 ($((($($flavor:tt)*), $string:expr),)*) => (
105 pub const fn one_of() -> &'static str {
106 concat!("one of: ", $($string, " ",)+)
109 pub fn from_str(s: &str) -> Option<Self> {
111 $($string => $($flavor)*,)+
116 pub fn desc(&self) -> &str {
118 $($($flavor)* => $string,)+
127 ((LinkerFlavor::Em), "em"),
128 ((LinkerFlavor::Gcc), "gcc"),
129 ((LinkerFlavor::Ld), "ld"),
130 ((LinkerFlavor::Msvc), "msvc"),
131 ((LinkerFlavor::Lld(LldFlavor::Wasm)), "wasm-ld"),
132 ((LinkerFlavor::Lld(LldFlavor::Ld64)), "ld64.lld"),
133 ((LinkerFlavor::Lld(LldFlavor::Ld)), "ld.lld"),
134 ((LinkerFlavor::Lld(LldFlavor::Link)), "lld-link"),
137 #[derive(Clone, Copy, Debug, PartialEq, Hash, RustcEncodable, RustcDecodable)]
138 pub enum PanicStrategy {
144 pub fn desc(&self) -> &str {
146 PanicStrategy::Unwind => "unwind",
147 PanicStrategy::Abort => "abort",
152 impl ToJson for PanicStrategy {
153 fn to_json(&self) -> Json {
155 PanicStrategy::Abort => "abort".to_json(),
156 PanicStrategy::Unwind => "unwind".to_json(),
161 #[derive(Clone, Copy, Debug, PartialEq, Hash, RustcEncodable, RustcDecodable)]
162 pub enum RelroLevel {
170 pub fn desc(&self) -> &str {
172 RelroLevel::Full => "full",
173 RelroLevel::Partial => "partial",
174 RelroLevel::Off => "off",
175 RelroLevel::None => "none",
180 impl FromStr for RelroLevel {
183 fn from_str(s: &str) -> Result<RelroLevel, ()> {
185 "full" => Ok(RelroLevel::Full),
186 "partial" => Ok(RelroLevel::Partial),
187 "off" => Ok(RelroLevel::Off),
188 "none" => Ok(RelroLevel::None),
194 impl ToJson for RelroLevel {
195 fn to_json(&self) -> Json {
197 RelroLevel::Full => "full".to_json(),
198 RelroLevel::Partial => "partial".to_json(),
199 RelroLevel::Off => "off".to_json(),
200 RelroLevel::None => "None".to_json(),
205 pub type LinkArgs = BTreeMap<LinkerFlavor, Vec<String>>;
206 pub type TargetResult = Result<Target, String>;
208 macro_rules! supported_targets {
209 ( $(($triple:expr, $module:ident),)+ ) => (
212 /// List of supported targets
213 const TARGETS: &'static [&'static str] = &[$($triple),*];
215 fn load_specific(target: &str) -> TargetResult {
219 let mut t = $module::target()?;
220 t.options.is_builtin = true;
222 // round-trip through the JSON parser to ensure at
223 // run-time that the parser works correctly
224 t = Target::from_json(t.to_json())?;
225 debug!("Got builtin target: {:?}", t);
229 _ => Err(format!("Unable to find target: {}", target))
233 pub fn get_targets() -> Box<dyn Iterator<Item=String>> {
234 Box::new(TARGETS.iter().filter_map(|t| -> Option<String> {
236 .and(Ok(t.to_string()))
242 mod test_json_encode_decode {
243 use serialize::json::ToJson;
245 $(use super::$module;)*
250 // Grab the TargetResult struct. If we successfully retrieved
251 // a Target, then the test JSON encoding/decoding can run for this
252 // Target on this testing platform (i.e., checking the iOS targets
253 // only on a Mac test platform).
254 let _ = $module::target().map(|original| {
255 let as_json = original.to_json();
256 let parsed = Target::from_json(as_json).unwrap();
257 assert_eq!(original, parsed);
266 ("x86_64-unknown-linux-gnu", x86_64_unknown_linux_gnu),
267 ("x86_64-unknown-linux-gnux32", x86_64_unknown_linux_gnux32),
268 ("i686-unknown-linux-gnu", i686_unknown_linux_gnu),
269 ("i586-unknown-linux-gnu", i586_unknown_linux_gnu),
270 ("mips-unknown-linux-gnu", mips_unknown_linux_gnu),
271 ("mips64-unknown-linux-gnuabi64", mips64_unknown_linux_gnuabi64),
272 ("mips64el-unknown-linux-gnuabi64", mips64el_unknown_linux_gnuabi64),
273 ("mipsel-unknown-linux-gnu", mipsel_unknown_linux_gnu),
274 ("powerpc-unknown-linux-gnu", powerpc_unknown_linux_gnu),
275 ("powerpc-unknown-linux-gnuspe", powerpc_unknown_linux_gnuspe),
276 ("powerpc64-unknown-linux-gnu", powerpc64_unknown_linux_gnu),
277 ("powerpc64le-unknown-linux-gnu", powerpc64le_unknown_linux_gnu),
278 ("powerpc64le-unknown-linux-musl", powerpc64le_unknown_linux_musl),
279 ("s390x-unknown-linux-gnu", s390x_unknown_linux_gnu),
280 ("sparc-unknown-linux-gnu", sparc_unknown_linux_gnu),
281 ("sparc64-unknown-linux-gnu", sparc64_unknown_linux_gnu),
282 ("arm-unknown-linux-gnueabi", arm_unknown_linux_gnueabi),
283 ("arm-unknown-linux-gnueabihf", arm_unknown_linux_gnueabihf),
284 ("arm-unknown-linux-musleabi", arm_unknown_linux_musleabi),
285 ("arm-unknown-linux-musleabihf", arm_unknown_linux_musleabihf),
286 ("armv4t-unknown-linux-gnueabi", armv4t_unknown_linux_gnueabi),
287 ("armv5te-unknown-linux-gnueabi", armv5te_unknown_linux_gnueabi),
288 ("armv5te-unknown-linux-musleabi", armv5te_unknown_linux_musleabi),
289 ("armv7-unknown-linux-gnueabihf", armv7_unknown_linux_gnueabihf),
290 ("armv7-unknown-linux-musleabihf", armv7_unknown_linux_musleabihf),
291 ("aarch64-unknown-linux-gnu", aarch64_unknown_linux_gnu),
293 ("aarch64-unknown-linux-musl", aarch64_unknown_linux_musl),
294 ("x86_64-unknown-linux-musl", x86_64_unknown_linux_musl),
295 ("i686-unknown-linux-musl", i686_unknown_linux_musl),
296 ("i586-unknown-linux-musl", i586_unknown_linux_musl),
297 ("mips-unknown-linux-musl", mips_unknown_linux_musl),
298 ("mipsel-unknown-linux-musl", mipsel_unknown_linux_musl),
300 ("mips-unknown-linux-uclibc", mips_unknown_linux_uclibc),
301 ("mipsel-unknown-linux-uclibc", mipsel_unknown_linux_uclibc),
303 ("i686-linux-android", i686_linux_android),
304 ("x86_64-linux-android", x86_64_linux_android),
305 ("arm-linux-androideabi", arm_linux_androideabi),
306 ("armv7-linux-androideabi", armv7_linux_androideabi),
307 ("aarch64-linux-android", aarch64_linux_android),
309 ("aarch64-unknown-freebsd", aarch64_unknown_freebsd),
310 ("i686-unknown-freebsd", i686_unknown_freebsd),
311 ("x86_64-unknown-freebsd", x86_64_unknown_freebsd),
313 ("i686-unknown-dragonfly", i686_unknown_dragonfly),
314 ("x86_64-unknown-dragonfly", x86_64_unknown_dragonfly),
316 ("x86_64-unknown-bitrig", x86_64_unknown_bitrig),
318 ("aarch64-unknown-openbsd", aarch64_unknown_openbsd),
319 ("i686-unknown-openbsd", i686_unknown_openbsd),
320 ("x86_64-unknown-openbsd", x86_64_unknown_openbsd),
322 ("aarch64-unknown-netbsd", aarch64_unknown_netbsd),
323 ("armv6-unknown-netbsd-eabihf", armv6_unknown_netbsd_eabihf),
324 ("armv7-unknown-netbsd-eabihf", armv7_unknown_netbsd_eabihf),
325 ("i686-unknown-netbsd", i686_unknown_netbsd),
326 ("powerpc-unknown-netbsd", powerpc_unknown_netbsd),
327 ("sparc64-unknown-netbsd", sparc64_unknown_netbsd),
328 ("x86_64-unknown-netbsd", x86_64_unknown_netbsd),
329 ("x86_64-rumprun-netbsd", x86_64_rumprun_netbsd),
331 ("i686-unknown-haiku", i686_unknown_haiku),
332 ("x86_64-unknown-haiku", x86_64_unknown_haiku),
334 ("x86_64-apple-darwin", x86_64_apple_darwin),
335 ("i686-apple-darwin", i686_apple_darwin),
337 ("aarch64-fuchsia", aarch64_fuchsia),
338 ("x86_64-fuchsia", x86_64_fuchsia),
340 ("x86_64-unknown-l4re-uclibc", x86_64_unknown_l4re_uclibc),
342 ("x86_64-unknown-redox", x86_64_unknown_redox),
344 ("i386-apple-ios", i386_apple_ios),
345 ("x86_64-apple-ios", x86_64_apple_ios),
346 ("aarch64-apple-ios", aarch64_apple_ios),
347 ("armv7-apple-ios", armv7_apple_ios),
348 ("armv7s-apple-ios", armv7s_apple_ios),
350 ("armebv7r-none-eabihf", armebv7r_none_eabihf),
352 ("x86_64-sun-solaris", x86_64_sun_solaris),
353 ("sparcv9-sun-solaris", sparcv9_sun_solaris),
355 ("x86_64-pc-windows-gnu", x86_64_pc_windows_gnu),
356 ("i686-pc-windows-gnu", i686_pc_windows_gnu),
358 ("aarch64-pc-windows-msvc", aarch64_pc_windows_msvc),
359 ("x86_64-pc-windows-msvc", x86_64_pc_windows_msvc),
360 ("i686-pc-windows-msvc", i686_pc_windows_msvc),
361 ("i586-pc-windows-msvc", i586_pc_windows_msvc),
363 ("asmjs-unknown-emscripten", asmjs_unknown_emscripten),
364 ("wasm32-unknown-emscripten", wasm32_unknown_emscripten),
365 ("wasm32-unknown-unknown", wasm32_unknown_unknown),
366 ("wasm32-experimental-emscripten", wasm32_experimental_emscripten),
368 ("thumbv6m-none-eabi", thumbv6m_none_eabi),
369 ("thumbv7m-none-eabi", thumbv7m_none_eabi),
370 ("thumbv7em-none-eabi", thumbv7em_none_eabi),
371 ("thumbv7em-none-eabihf", thumbv7em_none_eabihf),
373 ("msp430-none-elf", msp430_none_elf),
375 ("aarch64-unknown-cloudabi", aarch64_unknown_cloudabi),
376 ("armv7-unknown-cloudabi-eabihf", armv7_unknown_cloudabi_eabihf),
377 ("i686-unknown-cloudabi", i686_unknown_cloudabi),
378 ("x86_64-unknown-cloudabi", x86_64_unknown_cloudabi),
380 ("aarch64-unknown-hermit", aarch64_unknown_hermit),
381 ("x86_64-unknown-hermit", x86_64_unknown_hermit),
383 ("riscv32imac-unknown-none-elf", riscv32imac_unknown_none_elf),
385 ("aarch64-unknown-none", aarch64_unknown_none),
388 /// Everything `rustc` knows about how to compile for a specific target.
390 /// Every field here must be specified, and has no default value.
391 #[derive(PartialEq, Clone, Debug)]
393 /// Target triple to pass to LLVM.
394 pub llvm_target: String,
395 /// String to use as the `target_endian` `cfg` variable.
396 pub target_endian: String,
397 /// String to use as the `target_pointer_width` `cfg` variable.
398 pub target_pointer_width: String,
399 /// Width of c_int type
400 pub target_c_int_width: String,
401 /// OS name to use for conditional compilation.
402 pub target_os: String,
403 /// Environment name to use for conditional compilation.
404 pub target_env: String,
405 /// Vendor name to use for conditional compilation.
406 pub target_vendor: String,
407 /// Architecture to use for ABI considerations. Valid options: "x86",
408 /// "x86_64", "arm", "aarch64", "mips", "powerpc", and "powerpc64".
410 /// [Data layout](http://llvm.org/docs/LangRef.html#data-layout) to pass to LLVM.
411 pub data_layout: String,
413 pub linker_flavor: LinkerFlavor,
414 /// Optional settings with defaults.
415 pub options: TargetOptions,
418 pub trait HasTargetSpec: Copy {
419 fn target_spec(&self) -> &Target;
422 impl<'a> HasTargetSpec for &'a Target {
423 fn target_spec(&self) -> &Target {
428 /// Optional aspects of a target specification.
430 /// This has an implementation of `Default`, see each field for what the default is. In general,
431 /// these try to take "minimal defaults" that don't assume anything about the runtime they run in.
432 #[derive(PartialEq, Clone, Debug)]
433 pub struct TargetOptions {
434 /// Whether the target is built-in or loaded from a custom target specification.
435 pub is_builtin: bool,
438 pub linker: Option<String>,
440 /// Linker arguments that are passed *before* any user-defined libraries.
441 pub pre_link_args: LinkArgs, // ... unconditionally
442 pub pre_link_args_crt: LinkArgs, // ... when linking with a bundled crt
443 /// Objects to link before all others, always found within the
445 pub pre_link_objects_exe: Vec<String>, // ... when linking an executable, unconditionally
446 pub pre_link_objects_exe_crt: Vec<String>, // ... when linking an executable with a bundled crt
447 pub pre_link_objects_dll: Vec<String>, // ... when linking a dylib
448 /// Linker arguments that are unconditionally passed after any
449 /// user-defined but before post_link_objects. Standard platform
450 /// libraries that should be always be linked to, usually go here.
451 pub late_link_args: LinkArgs,
452 /// Objects to link after all others, always found within the
454 pub post_link_objects: Vec<String>, // ... unconditionally
455 pub post_link_objects_crt: Vec<String>, // ... when linking with a bundled crt
456 /// Linker arguments that are unconditionally passed *after* any
457 /// user-defined libraries.
458 pub post_link_args: LinkArgs,
460 /// Environment variables to be set before invoking the linker.
461 pub link_env: Vec<(String, String)>,
463 /// Extra arguments to pass to the external assembler (when used)
464 pub asm_args: Vec<String>,
466 /// Default CPU to pass to LLVM. Corresponds to `llc -mcpu=$cpu`. Defaults
469 /// Default target features to pass to LLVM. These features will *always* be
470 /// passed, and cannot be disabled even via `-C`. Corresponds to `llc
471 /// -mattr=$features`.
472 pub features: String,
473 /// Whether dynamic linking is available on this target. Defaults to false.
474 pub dynamic_linking: bool,
475 /// If dynamic linking is available, whether only cdylibs are supported.
476 pub only_cdylib: bool,
477 /// Whether executables are available on this target. iOS, for example, only allows static
478 /// libraries. Defaults to false.
479 pub executables: bool,
480 /// Relocation model to use in object file. Corresponds to `llc
481 /// -relocation-model=$relocation_model`. Defaults to "pic".
482 pub relocation_model: String,
483 /// Code model to use. Corresponds to `llc -code-model=$code_model`.
484 pub code_model: Option<String>,
485 /// TLS model to use. Options are "global-dynamic" (default), "local-dynamic", "initial-exec"
486 /// and "local-exec". This is similar to the -ftls-model option in GCC/Clang.
487 pub tls_model: String,
488 /// Do not emit code that uses the "red zone", if the ABI has one. Defaults to false.
489 pub disable_redzone: bool,
490 /// Eliminate frame pointers from stack frames if possible. Defaults to true.
491 pub eliminate_frame_pointer: bool,
492 /// Emit each function in its own section. Defaults to true.
493 pub function_sections: bool,
494 /// String to prepend to the name of every dynamic library. Defaults to "lib".
495 pub dll_prefix: String,
496 /// String to append to the name of every dynamic library. Defaults to ".so".
497 pub dll_suffix: String,
498 /// String to append to the name of every executable.
499 pub exe_suffix: String,
500 /// String to prepend to the name of every static library. Defaults to "lib".
501 pub staticlib_prefix: String,
502 /// String to append to the name of every static library. Defaults to ".a".
503 pub staticlib_suffix: String,
504 /// OS family to use for conditional compilation. Valid options: "unix", "windows".
505 pub target_family: Option<String>,
506 /// Whether the target toolchain's ABI supports returning small structs as an integer.
507 pub abi_return_struct_as_int: bool,
508 /// Whether the target toolchain is like macOS's. Only useful for compiling against iOS/macOS,
509 /// in particular running dsymutil and some other stuff like `-dead_strip`. Defaults to false.
510 pub is_like_osx: bool,
511 /// Whether the target toolchain is like Solaris's.
512 /// Only useful for compiling against Illumos/Solaris,
513 /// as they have a different set of linker flags. Defaults to false.
514 pub is_like_solaris: bool,
515 /// Whether the target toolchain is like Windows'. Only useful for compiling against Windows,
516 /// only really used for figuring out how to find libraries, since Windows uses its own
517 /// library naming convention. Defaults to false.
518 pub is_like_windows: bool,
519 pub is_like_msvc: bool,
520 /// Whether the target toolchain is like Android's. Only useful for compiling against Android.
521 /// Defaults to false.
522 pub is_like_android: bool,
523 /// Whether the target toolchain is like Emscripten's. Only useful for compiling with
524 /// Emscripten toolchain.
525 /// Defaults to false.
526 pub is_like_emscripten: bool,
527 /// Whether the linker support GNU-like arguments such as -O. Defaults to false.
528 pub linker_is_gnu: bool,
529 /// The MinGW toolchain has a known issue that prevents it from correctly
530 /// handling COFF object files with more than 2<sup>15</sup> sections. Since each weak
531 /// symbol needs its own COMDAT section, weak linkage implies a large
532 /// number sections that easily exceeds the given limit for larger
533 /// codebases. Consequently we want a way to disallow weak linkage on some
535 pub allows_weak_linkage: bool,
536 /// Whether the linker support rpaths or not. Defaults to false.
538 /// Whether to disable linking to the default libraries, typically corresponds
539 /// to `-nodefaultlibs`. Defaults to true.
540 pub no_default_libraries: bool,
541 /// Dynamically linked executables can be compiled as position independent
542 /// if the default relocation model of position independent code is not
543 /// changed. This is a requirement to take advantage of ASLR, as otherwise
544 /// the functions in the executable are not randomized and can be used
545 /// during an exploit of a vulnerability in any code.
546 pub position_independent_executables: bool,
547 /// Either partial, full, or off. Full RELRO makes the dynamic linker
548 /// resolve all symbols at startup and marks the GOT read-only before
549 /// starting the program, preventing overwriting the GOT.
550 pub relro_level: RelroLevel,
551 /// Format that archives should be emitted in. This affects whether we use
552 /// LLVM to assemble an archive or fall back to the system linker, and
553 /// currently only "gnu" is used to fall into LLVM. Unknown strings cause
554 /// the system linker to be used.
555 pub archive_format: String,
556 /// Is asm!() allowed? Defaults to true.
558 /// Whether the target uses a custom unwind resumption routine.
559 /// By default LLVM lowers `resume` instructions into calls to `_Unwind_Resume`
560 /// defined in libgcc. If this option is enabled, the target must provide
561 /// `eh_unwind_resume` lang item.
562 pub custom_unwind_resume: bool,
564 /// If necessary, a different crate to link exe allocators by default
565 pub exe_allocation_crate: Option<String>,
567 /// Flag indicating whether ELF TLS (e.g. #[thread_local]) is available for
569 pub has_elf_tls: bool,
570 // This is mainly for easy compatibility with emscripten.
571 // If we give emcc .o files that are actually .bc files it
573 pub obj_is_bitcode: bool,
575 // LLVM can't produce object files for this target. Instead, we'll make LLVM
576 // emit assembly and then use `gcc` to turn that assembly into an object
578 pub no_integrated_as: bool,
580 /// Don't use this field; instead use the `.min_atomic_width()` method.
581 pub min_atomic_width: Option<u64>,
583 /// Don't use this field; instead use the `.max_atomic_width()` method.
584 pub max_atomic_width: Option<u64>,
586 /// Whether the target supports atomic CAS operations natively
587 pub atomic_cas: bool,
589 /// Panic strategy: "unwind" or "abort"
590 pub panic_strategy: PanicStrategy,
592 /// A blacklist of ABIs unsupported by the current target. Note that generic
593 /// ABIs are considered to be supported on all platforms and cannot be blacklisted.
594 pub abi_blacklist: Vec<Abi>,
596 /// Whether or not linking dylibs to a static CRT is allowed.
597 pub crt_static_allows_dylibs: bool,
598 /// Whether or not the CRT is statically linked by default.
599 pub crt_static_default: bool,
600 /// Whether or not crt-static is respected by the compiler (or is a no-op).
601 pub crt_static_respected: bool,
603 /// Whether or not stack probes (__rust_probestack) are enabled
604 pub stack_probes: bool,
606 /// The minimum alignment for global symbols.
607 pub min_global_align: Option<u64>,
609 /// Default number of codegen units to use in debug mode
610 pub default_codegen_units: Option<u64>,
612 /// Whether to generate trap instructions in places where optimization would
613 /// otherwise produce control flow that falls through into unrelated memory.
614 pub trap_unreachable: bool,
616 /// This target requires everything to be compiled with LTO to emit a final
617 /// executable, aka there is no native linker for this target.
618 pub requires_lto: bool,
620 /// This target has no support for threads.
621 pub singlethread: bool,
623 /// Whether library functions call lowering/optimization is disabled in LLVM
624 /// for this target unconditionally.
625 pub no_builtins: bool,
627 /// Whether to lower 128-bit operations to compiler_builtins calls. Use if
628 /// your backend only supports 64-bit and smaller math.
629 pub i128_lowering: bool,
631 /// The codegen backend to use for this target, typically "llvm"
632 pub codegen_backend: String,
634 /// The default visibility for symbols in this target should be "hidden"
635 /// rather than "default"
636 pub default_hidden_visibility: bool,
638 /// Whether or not bitcode is embedded in object files
639 pub embed_bitcode: bool,
641 /// Whether a .debug_gdb_scripts section will be added to the output object file
642 pub emit_debug_gdb_scripts: bool,
644 /// Whether or not to unconditionally `uwtable` attributes on functions,
645 /// typically because the platform needs to unwind for things like stack
647 pub requires_uwtable: bool,
650 impl Default for TargetOptions {
651 /// Create a set of "sane defaults" for any target. This is still
652 /// incomplete, and if used for compilation, will certainly not work.
653 fn default() -> TargetOptions {
656 linker: option_env!("CFG_DEFAULT_LINKER").map(|s| s.to_string()),
657 pre_link_args: LinkArgs::new(),
658 pre_link_args_crt: LinkArgs::new(),
659 post_link_args: LinkArgs::new(),
660 asm_args: Vec::new(),
661 cpu: "generic".to_string(),
662 features: "".to_string(),
663 dynamic_linking: false,
666 relocation_model: "pic".to_string(),
668 tls_model: "global-dynamic".to_string(),
669 disable_redzone: false,
670 eliminate_frame_pointer: true,
671 function_sections: true,
672 dll_prefix: "lib".to_string(),
673 dll_suffix: ".so".to_string(),
674 exe_suffix: "".to_string(),
675 staticlib_prefix: "lib".to_string(),
676 staticlib_suffix: ".a".to_string(),
678 abi_return_struct_as_int: false,
680 is_like_solaris: false,
681 is_like_windows: false,
682 is_like_android: false,
683 is_like_emscripten: false,
685 linker_is_gnu: false,
686 allows_weak_linkage: true,
688 no_default_libraries: true,
689 position_independent_executables: false,
690 relro_level: RelroLevel::None,
691 pre_link_objects_exe: Vec::new(),
692 pre_link_objects_exe_crt: Vec::new(),
693 pre_link_objects_dll: Vec::new(),
694 post_link_objects: Vec::new(),
695 post_link_objects_crt: Vec::new(),
696 late_link_args: LinkArgs::new(),
697 link_env: Vec::new(),
698 archive_format: "gnu".to_string(),
699 custom_unwind_resume: false,
700 exe_allocation_crate: None,
703 obj_is_bitcode: false,
704 no_integrated_as: false,
705 min_atomic_width: None,
706 max_atomic_width: None,
708 panic_strategy: PanicStrategy::Unwind,
709 abi_blacklist: vec![],
710 crt_static_allows_dylibs: false,
711 crt_static_default: false,
712 crt_static_respected: false,
714 min_global_align: None,
715 default_codegen_units: None,
716 trap_unreachable: true,
720 i128_lowering: false,
721 codegen_backend: "llvm".to_string(),
722 default_hidden_visibility: false,
723 embed_bitcode: false,
724 emit_debug_gdb_scripts: true,
725 requires_uwtable: false,
731 /// Given a function ABI, turn "System" into the correct ABI for this target.
732 pub fn adjust_abi(&self, abi: Abi) -> Abi {
735 if self.options.is_like_windows && self.arch == "x86" {
745 /// Minimum integer size in bits that this target can perform atomic
747 pub fn min_atomic_width(&self) -> u64 {
748 self.options.min_atomic_width.unwrap_or(8)
751 /// Maximum integer size in bits that this target can perform atomic
753 pub fn max_atomic_width(&self) -> u64 {
754 self.options.max_atomic_width.unwrap_or_else(|| self.target_pointer_width.parse().unwrap())
757 pub fn is_abi_supported(&self, abi: Abi) -> bool {
758 abi.generic() || !self.options.abi_blacklist.contains(&abi)
761 /// Load a target descriptor from a JSON object.
762 pub fn from_json(obj: Json) -> TargetResult {
763 // While ugly, this code must remain this way to retain
764 // compatibility with existing JSON fields and the internal
765 // expected naming of the Target and TargetOptions structs.
766 // To ensure compatibility is retained, the built-in targets
767 // are round-tripped through this code to catch cases where
768 // the JSON parser is not updated to match the structs.
770 let get_req_field = |name: &str| {
772 .map(|s| s.as_string())
773 .and_then(|os| os.map(|s| s.to_string()))
774 .ok_or_else(|| format!("Field {} in target specification is required", name))
777 let get_opt_field = |name: &str, default: &str| {
778 obj.find(name).and_then(|s| s.as_string())
779 .map(|s| s.to_string())
780 .unwrap_or_else(|| default.to_string())
783 let mut base = Target {
784 llvm_target: get_req_field("llvm-target")?,
785 target_endian: get_req_field("target-endian")?,
786 target_pointer_width: get_req_field("target-pointer-width")?,
787 target_c_int_width: get_req_field("target-c-int-width")?,
788 data_layout: get_req_field("data-layout")?,
789 arch: get_req_field("arch")?,
790 target_os: get_req_field("os")?,
791 target_env: get_opt_field("env", ""),
792 target_vendor: get_opt_field("vendor", "unknown"),
793 linker_flavor: LinkerFlavor::from_str(&*get_req_field("linker-flavor")?)
795 format!("linker flavor must be {}", LinkerFlavor::one_of())
797 options: Default::default(),
801 ($key_name:ident) => ( {
802 let name = (stringify!($key_name)).replace("_", "-");
803 obj.find(&name[..]).map(|o| o.as_string()
804 .map(|s| base.options.$key_name = s.to_string()));
806 ($key_name:ident, bool) => ( {
807 let name = (stringify!($key_name)).replace("_", "-");
809 .map(|o| o.as_boolean()
810 .map(|s| base.options.$key_name = s));
812 ($key_name:ident, Option<u64>) => ( {
813 let name = (stringify!($key_name)).replace("_", "-");
816 .map(|s| base.options.$key_name = Some(s)));
818 ($key_name:ident, PanicStrategy) => ( {
819 let name = (stringify!($key_name)).replace("_", "-");
820 obj.find(&name[..]).and_then(|o| o.as_string().and_then(|s| {
822 "unwind" => base.options.$key_name = PanicStrategy::Unwind,
823 "abort" => base.options.$key_name = PanicStrategy::Abort,
824 _ => return Some(Err(format!("'{}' is not a valid value for \
825 panic-strategy. Use 'unwind' or 'abort'.",
829 })).unwrap_or(Ok(()))
831 ($key_name:ident, RelroLevel) => ( {
832 let name = (stringify!($key_name)).replace("_", "-");
833 obj.find(&name[..]).and_then(|o| o.as_string().and_then(|s| {
834 match s.parse::<RelroLevel>() {
835 Ok(level) => base.options.$key_name = level,
836 _ => return Some(Err(format!("'{}' is not a valid value for \
837 relro-level. Use 'full', 'partial, or 'off'.",
841 })).unwrap_or(Ok(()))
843 ($key_name:ident, list) => ( {
844 let name = (stringify!($key_name)).replace("_", "-");
845 obj.find(&name[..]).map(|o| o.as_array()
846 .map(|v| base.options.$key_name = v.iter()
847 .map(|a| a.as_string().unwrap().to_string()).collect()
851 ($key_name:ident, optional) => ( {
852 let name = (stringify!($key_name)).replace("_", "-");
853 if let Some(o) = obj.find(&name[..]) {
854 base.options.$key_name = o
856 .map(|s| s.to_string() );
859 ($key_name:ident, LinkerFlavor) => ( {
860 let name = (stringify!($key_name)).replace("_", "-");
861 obj.find(&name[..]).and_then(|o| o.as_string().map(|s| {
862 LinkerFlavor::from_str(&s).ok_or_else(|| {
863 Err(format!("'{}' is not a valid value for linker-flavor. \
864 Use 'em', 'gcc', 'ld' or 'msvc.", s))
866 })).unwrap_or(Ok(()))
868 ($key_name:ident, link_args) => ( {
869 let name = (stringify!($key_name)).replace("_", "-");
870 if let Some(val) = obj.find(&name[..]) {
871 let obj = val.as_object().ok_or_else(|| format!("{}: expected a \
872 JSON object with fields per linker-flavor.", name))?;
873 let mut args = LinkArgs::new();
875 let flavor = LinkerFlavor::from_str(&k).ok_or_else(|| {
876 format!("{}: '{}' is not a valid value for linker-flavor. \
877 Use 'em', 'gcc', 'ld' or 'msvc'", name, k)
880 let v = v.as_array().ok_or_else(||
881 format!("{}.{}: expected a JSON array", name, k)
882 )?.iter().enumerate()
884 let s = s.as_string().ok_or_else(||
885 format!("{}.{}[{}]: expected a JSON string", name, k, i))?;
888 .collect::<Result<Vec<_>, String>>()?;
890 args.insert(flavor, v);
892 base.options.$key_name = args;
895 ($key_name:ident, env) => ( {
896 let name = (stringify!($key_name)).replace("_", "-");
897 if let Some(a) = obj.find(&name[..]).and_then(|o| o.as_array()) {
899 if let Some(s) = o.as_string() {
900 let p = s.split('=').collect::<Vec<_>>();
902 let k = p[0].to_string();
903 let v = p[1].to_string();
904 base.options.$key_name.push((k, v));
912 key!(is_builtin, bool);
913 key!(linker, optional);
914 key!(pre_link_args, link_args);
915 key!(pre_link_args_crt, link_args);
916 key!(pre_link_objects_exe, list);
917 key!(pre_link_objects_exe_crt, list);
918 key!(pre_link_objects_dll, list);
919 key!(late_link_args, link_args);
920 key!(post_link_objects, list);
921 key!(post_link_objects_crt, list);
922 key!(post_link_args, link_args);
924 key!(asm_args, list);
927 key!(dynamic_linking, bool);
928 key!(only_cdylib, bool);
929 key!(executables, bool);
930 key!(relocation_model);
931 key!(code_model, optional);
933 key!(disable_redzone, bool);
934 key!(eliminate_frame_pointer, bool);
935 key!(function_sections, bool);
939 key!(staticlib_prefix);
940 key!(staticlib_suffix);
941 key!(target_family, optional);
942 key!(abi_return_struct_as_int, bool);
943 key!(is_like_osx, bool);
944 key!(is_like_solaris, bool);
945 key!(is_like_windows, bool);
946 key!(is_like_msvc, bool);
947 key!(is_like_emscripten, bool);
948 key!(is_like_android, bool);
949 key!(linker_is_gnu, bool);
950 key!(allows_weak_linkage, bool);
951 key!(has_rpath, bool);
952 key!(no_default_libraries, bool);
953 key!(position_independent_executables, bool);
954 try!(key!(relro_level, RelroLevel));
955 key!(archive_format);
956 key!(allow_asm, bool);
957 key!(custom_unwind_resume, bool);
958 key!(exe_allocation_crate, optional);
959 key!(has_elf_tls, bool);
960 key!(obj_is_bitcode, bool);
961 key!(no_integrated_as, bool);
962 key!(max_atomic_width, Option<u64>);
963 key!(min_atomic_width, Option<u64>);
964 key!(atomic_cas, bool);
965 try!(key!(panic_strategy, PanicStrategy));
966 key!(crt_static_allows_dylibs, bool);
967 key!(crt_static_default, bool);
968 key!(crt_static_respected, bool);
969 key!(stack_probes, bool);
970 key!(min_global_align, Option<u64>);
971 key!(default_codegen_units, Option<u64>);
972 key!(trap_unreachable, bool);
973 key!(requires_lto, bool);
974 key!(singlethread, bool);
975 key!(no_builtins, bool);
976 key!(codegen_backend);
977 key!(default_hidden_visibility, bool);
978 key!(embed_bitcode, bool);
979 key!(emit_debug_gdb_scripts, bool);
980 key!(requires_uwtable, bool);
982 if let Some(array) = obj.find("abi-blacklist").and_then(Json::as_array) {
983 for name in array.iter().filter_map(|abi| abi.as_string()) {
984 match lookup_abi(name) {
987 return Err(format!("The ABI \"{}\" is considered to be supported on \
988 all targets and cannot be blacklisted", abi))
991 base.options.abi_blacklist.push(abi)
993 None => return Err(format!("Unknown ABI \"{}\" in target specification", name))
1001 /// Search RUST_TARGET_PATH for a JSON file specifying the given target
1002 /// triple. Note that it could also just be a bare filename already, so also
1003 /// check for that. If one of the hardcoded targets we know about, just
1004 /// return it directly.
1006 /// The error string could come from any of the APIs called, including
1007 /// filesystem access and JSON decoding.
1008 pub fn search(target_triple: &TargetTriple) -> Result<Target, String> {
1011 use serialize::json;
1013 fn load_file(path: &Path) -> Result<Target, String> {
1014 let contents = fs::read(path).map_err(|e| e.to_string())?;
1015 let obj = json::from_reader(&mut &contents[..])
1016 .map_err(|e| e.to_string())?;
1017 Target::from_json(obj)
1020 match *target_triple {
1021 TargetTriple::TargetTriple(ref target_triple) => {
1022 // check if triple is in list of supported targets
1023 if let Ok(t) = load_specific(target_triple) {
1027 // search for a file named `target_triple`.json in RUST_TARGET_PATH
1029 let mut target = target_triple.to_string();
1030 target.push_str(".json");
1031 PathBuf::from(target)
1034 let target_path = env::var_os("RUST_TARGET_PATH").unwrap_or_default();
1036 // FIXME 16351: add a sane default search path?
1038 for dir in env::split_paths(&target_path) {
1039 let p = dir.join(&path);
1041 return load_file(&p);
1044 Err(format!("Could not find specification for target {:?}", target_triple))
1046 TargetTriple::TargetPath(ref target_path) => {
1047 if target_path.is_file() {
1048 return load_file(&target_path);
1050 Err(format!("Target path {:?} is not a valid file", target_path))
1056 impl ToJson for Target {
1057 fn to_json(&self) -> Json {
1058 let mut d = BTreeMap::new();
1059 let default: TargetOptions = Default::default();
1061 macro_rules! target_val {
1062 ($attr:ident) => ( {
1063 let name = (stringify!($attr)).replace("_", "-");
1064 d.insert(name.to_string(), self.$attr.to_json());
1066 ($attr:ident, $key_name:expr) => ( {
1067 let name = $key_name;
1068 d.insert(name.to_string(), self.$attr.to_json());
1072 macro_rules! target_option_val {
1073 ($attr:ident) => ( {
1074 let name = (stringify!($attr)).replace("_", "-");
1075 if default.$attr != self.options.$attr {
1076 d.insert(name.to_string(), self.options.$attr.to_json());
1079 ($attr:ident, $key_name:expr) => ( {
1080 let name = $key_name;
1081 if default.$attr != self.options.$attr {
1082 d.insert(name.to_string(), self.options.$attr.to_json());
1085 (link_args - $attr:ident) => ( {
1086 let name = (stringify!($attr)).replace("_", "-");
1087 if default.$attr != self.options.$attr {
1088 let obj = self.options.$attr
1090 .map(|(k, v)| (k.desc().to_owned(), v.clone()))
1091 .collect::<BTreeMap<_, _>>();
1092 d.insert(name.to_string(), obj.to_json());
1095 (env - $attr:ident) => ( {
1096 let name = (stringify!($attr)).replace("_", "-");
1097 if default.$attr != self.options.$attr {
1098 let obj = self.options.$attr
1100 .map(|&(ref k, ref v)| k.clone() + "=" + &v)
1101 .collect::<Vec<_>>();
1102 d.insert(name.to_string(), obj.to_json());
1108 target_val!(llvm_target);
1109 target_val!(target_endian);
1110 target_val!(target_pointer_width);
1111 target_val!(target_c_int_width);
1113 target_val!(target_os, "os");
1114 target_val!(target_env, "env");
1115 target_val!(target_vendor, "vendor");
1116 target_val!(data_layout);
1117 target_val!(linker_flavor);
1119 target_option_val!(is_builtin);
1120 target_option_val!(linker);
1121 target_option_val!(link_args - pre_link_args);
1122 target_option_val!(link_args - pre_link_args_crt);
1123 target_option_val!(pre_link_objects_exe);
1124 target_option_val!(pre_link_objects_exe_crt);
1125 target_option_val!(pre_link_objects_dll);
1126 target_option_val!(link_args - late_link_args);
1127 target_option_val!(post_link_objects);
1128 target_option_val!(post_link_objects_crt);
1129 target_option_val!(link_args - post_link_args);
1130 target_option_val!(env - link_env);
1131 target_option_val!(asm_args);
1132 target_option_val!(cpu);
1133 target_option_val!(features);
1134 target_option_val!(dynamic_linking);
1135 target_option_val!(only_cdylib);
1136 target_option_val!(executables);
1137 target_option_val!(relocation_model);
1138 target_option_val!(code_model);
1139 target_option_val!(tls_model);
1140 target_option_val!(disable_redzone);
1141 target_option_val!(eliminate_frame_pointer);
1142 target_option_val!(function_sections);
1143 target_option_val!(dll_prefix);
1144 target_option_val!(dll_suffix);
1145 target_option_val!(exe_suffix);
1146 target_option_val!(staticlib_prefix);
1147 target_option_val!(staticlib_suffix);
1148 target_option_val!(target_family);
1149 target_option_val!(abi_return_struct_as_int);
1150 target_option_val!(is_like_osx);
1151 target_option_val!(is_like_solaris);
1152 target_option_val!(is_like_windows);
1153 target_option_val!(is_like_msvc);
1154 target_option_val!(is_like_emscripten);
1155 target_option_val!(is_like_android);
1156 target_option_val!(linker_is_gnu);
1157 target_option_val!(allows_weak_linkage);
1158 target_option_val!(has_rpath);
1159 target_option_val!(no_default_libraries);
1160 target_option_val!(position_independent_executables);
1161 target_option_val!(relro_level);
1162 target_option_val!(archive_format);
1163 target_option_val!(allow_asm);
1164 target_option_val!(custom_unwind_resume);
1165 target_option_val!(exe_allocation_crate);
1166 target_option_val!(has_elf_tls);
1167 target_option_val!(obj_is_bitcode);
1168 target_option_val!(no_integrated_as);
1169 target_option_val!(min_atomic_width);
1170 target_option_val!(max_atomic_width);
1171 target_option_val!(atomic_cas);
1172 target_option_val!(panic_strategy);
1173 target_option_val!(crt_static_allows_dylibs);
1174 target_option_val!(crt_static_default);
1175 target_option_val!(crt_static_respected);
1176 target_option_val!(stack_probes);
1177 target_option_val!(min_global_align);
1178 target_option_val!(default_codegen_units);
1179 target_option_val!(trap_unreachable);
1180 target_option_val!(requires_lto);
1181 target_option_val!(singlethread);
1182 target_option_val!(no_builtins);
1183 target_option_val!(codegen_backend);
1184 target_option_val!(default_hidden_visibility);
1185 target_option_val!(embed_bitcode);
1186 target_option_val!(emit_debug_gdb_scripts);
1187 target_option_val!(requires_uwtable);
1189 if default.abi_blacklist != self.options.abi_blacklist {
1190 d.insert("abi-blacklist".to_string(), self.options.abi_blacklist.iter()
1191 .map(|&name| Abi::name(name).to_json())
1192 .collect::<Vec<_>>().to_json());
1199 fn maybe_jemalloc() -> Option<String> {
1200 if cfg!(feature = "jemalloc") {
1201 Some("alloc_jemalloc".to_string())
1207 /// Either a target triple string or a path to a JSON file.
1208 #[derive(PartialEq, Clone, Debug, Hash, RustcEncodable, RustcDecodable)]
1209 pub enum TargetTriple {
1210 TargetTriple(String),
1211 TargetPath(PathBuf),
1215 /// Creates a target triple from the passed target triple string.
1216 pub fn from_triple(triple: &str) -> Self {
1217 TargetTriple::TargetTriple(triple.to_string())
1220 /// Creates a target triple from the passed target path.
1221 pub fn from_path(path: &Path) -> Result<Self, io::Error> {
1222 let canonicalized_path = path.canonicalize()?;
1223 Ok(TargetTriple::TargetPath(canonicalized_path))
1226 /// Returns a string triple for this target.
1228 /// If this target is a path, the file name (without extension) is returned.
1229 pub fn triple(&self) -> &str {
1231 TargetTriple::TargetTriple(ref triple) => triple,
1232 TargetTriple::TargetPath(ref path) => {
1233 path.file_stem().expect("target path must not be empty").to_str()
1234 .expect("target path must be valid unicode")
1239 /// Returns an extended string triple for this target.
1241 /// If this target is a path, a hash of the path is appended to the triple returned
1243 pub fn debug_triple(&self) -> String {
1244 use std::hash::{Hash, Hasher};
1245 use std::collections::hash_map::DefaultHasher;
1247 let triple = self.triple();
1248 if let TargetTriple::TargetPath(ref path) = *self {
1249 let mut hasher = DefaultHasher::new();
1250 path.hash(&mut hasher);
1251 let hash = hasher.finish();
1252 format!("{}-{}", triple, hash)
1259 impl fmt::Display for TargetTriple {
1260 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1261 write!(f, "{}", self.debug_triple())