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Commit | Line | Data |
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a1dfa0c6 | 1 | use super::archive; |
dfeec247 XL |
2 | use super::command::Command; |
3 | use super::symbol_export; | |
f035d41b | 4 | use rustc_span::symbol::sym; |
a1dfa0c6 | 5 | |
cc61c64b | 6 | use std::ffi::{OsStr, OsString}; |
e9174d1e | 7 | use std::fs::{self, File}; |
e9174d1e | 8 | use std::io::prelude::*; |
9e0c209e | 9 | use std::io::{self, BufWriter}; |
ba9703b0 | 10 | use std::mem; |
62682a34 | 11 | use std::path::{Path, PathBuf}; |
3157f602 | 12 | |
ba9703b0 | 13 | use rustc_data_structures::fx::FxHashMap; |
dfeec247 | 14 | use rustc_hir::def_id::{CrateNum, LOCAL_CRATE}; |
ba9703b0 XL |
15 | use rustc_middle::middle::dependency_format::Linkage; |
16 | use rustc_middle::ty::TyCtxt; | |
416331ca | 17 | use rustc_serialize::{json, Encoder}; |
f9f354fc | 18 | use rustc_session::config::{self, CrateType, DebugInfo, LinkerPluginLto, Lto, OptLevel, Strip}; |
ba9703b0 | 19 | use rustc_session::Session; |
dfeec247 | 20 | use rustc_span::symbol::Symbol; |
f9f354fc XL |
21 | use rustc_target::spec::{LinkOutputKind, LinkerFlavor, LldFlavor}; |
22 | ||
23 | /// Disables non-English messages from localized linkers. | |
24 | /// Such messages may cause issues with text encoding on Windows (#35785) | |
25 | /// and prevent inspection of linker output in case of errors, which we occasionally do. | |
26 | /// This should be acceptable because other messages from rustc are in English anyway, | |
27 | /// and may also be desirable to improve searchability of the linker diagnostics. | |
28 | pub fn disable_localization(linker: &mut Command) { | |
29 | // No harm in setting both env vars simultaneously. | |
30 | // Unix-style linkers. | |
31 | linker.env("LC_ALL", "C"); | |
32 | // MSVC's `link.exe`. | |
33 | linker.env("VSLANG", "1033"); | |
34 | } | |
3157f602 XL |
35 | |
36 | /// For all the linkers we support, and information they might | |
37 | /// need out of the shared crate context before we get rid of it. | |
3dfed10e | 38 | #[derive(Encodable, Decodable)] |
3157f602 | 39 | pub struct LinkerInfo { |
b7449926 | 40 | exports: FxHashMap<CrateType, Vec<String>>, |
3157f602 XL |
41 | } |
42 | ||
ea8adc8c | 43 | impl LinkerInfo { |
dc9dc135 | 44 | pub fn new(tcx: TyCtxt<'_>) -> LinkerInfo { |
3157f602 | 45 | LinkerInfo { |
dfeec247 XL |
46 | exports: tcx |
47 | .sess | |
f9f354fc | 48 | .crate_types() |
dfeec247 XL |
49 | .iter() |
50 | .map(|&c| (c, exported_symbols(tcx, c))) | |
51 | .collect(), | |
3157f602 XL |
52 | } |
53 | } | |
54 | ||
a1dfa0c6 XL |
55 | pub fn to_linker<'a>( |
56 | &'a self, | |
57 | cmd: Command, | |
58 | sess: &'a Session, | |
59 | flavor: LinkerFlavor, | |
60 | target_cpu: &'a str, | |
dfeec247 | 61 | ) -> Box<dyn Linker + 'a> { |
b7449926 | 62 | match flavor { |
dfeec247 XL |
63 | LinkerFlavor::Lld(LldFlavor::Link) | LinkerFlavor::Msvc => { |
64 | Box::new(MsvcLinker { cmd, sess, info: self }) as Box<dyn Linker> | |
cc61c64b | 65 | } |
dfeec247 XL |
66 | LinkerFlavor::Em => Box::new(EmLinker { cmd, sess, info: self }) as Box<dyn Linker>, |
67 | LinkerFlavor::Gcc => Box::new(GccLinker { | |
68 | cmd, | |
69 | sess, | |
70 | info: self, | |
71 | hinted_static: false, | |
72 | is_ld: false, | |
73 | target_cpu, | |
74 | }) as Box<dyn Linker>, | |
75 | ||
76 | LinkerFlavor::Lld(LldFlavor::Ld) | |
77 | | LinkerFlavor::Lld(LldFlavor::Ld64) | |
78 | | LinkerFlavor::Ld => Box::new(GccLinker { | |
79 | cmd, | |
80 | sess, | |
81 | info: self, | |
82 | hinted_static: false, | |
83 | is_ld: true, | |
84 | target_cpu, | |
85 | }) as Box<dyn Linker>, | |
0531ce1d XL |
86 | |
87 | LinkerFlavor::Lld(LldFlavor::Wasm) => { | |
0731742a | 88 | Box::new(WasmLd::new(cmd, sess, self)) as Box<dyn Linker> |
abe05a73 | 89 | } |
9fa01778 | 90 | |
dfeec247 | 91 | LinkerFlavor::PtxLinker => Box::new(PtxLinker { cmd, sess }) as Box<dyn Linker>, |
3157f602 XL |
92 | } |
93 | } | |
94 | } | |
62682a34 | 95 | |
9fa01778 | 96 | /// Linker abstraction used by `back::link` to build up the command to invoke a |
62682a34 SL |
97 | /// linker. |
98 | /// | |
99 | /// This trait is the total list of requirements needed by `back::link` and | |
100 | /// represents the meaning of each option being passed down. This trait is then | |
101 | /// used to dispatch on whether a GNU-like linker (generally `ld.exe`) or an | |
0731742a | 102 | /// MSVC linker (e.g., `link.exe`) is being used. |
62682a34 | 103 | pub trait Linker { |
ba9703b0 | 104 | fn cmd(&mut self) -> &mut Command; |
f9f354fc | 105 | fn set_output_kind(&mut self, output_kind: LinkOutputKind, out_filename: &Path); |
e1599b0c XL |
106 | fn link_dylib(&mut self, lib: Symbol); |
107 | fn link_rust_dylib(&mut self, lib: Symbol, path: &Path); | |
108 | fn link_framework(&mut self, framework: Symbol); | |
109 | fn link_staticlib(&mut self, lib: Symbol); | |
62682a34 | 110 | fn link_rlib(&mut self, lib: &Path); |
c1a9b12d | 111 | fn link_whole_rlib(&mut self, lib: &Path); |
e1599b0c | 112 | fn link_whole_staticlib(&mut self, lib: Symbol, search_path: &[PathBuf]); |
62682a34 SL |
113 | fn include_path(&mut self, path: &Path); |
114 | fn framework_path(&mut self, path: &Path); | |
115 | fn output_filename(&mut self, path: &Path); | |
116 | fn add_object(&mut self, path: &Path); | |
a7813a04 | 117 | fn gc_sections(&mut self, keep_metadata: bool); |
3b2f2976 | 118 | fn full_relro(&mut self); |
0531ce1d XL |
119 | fn partial_relro(&mut self); |
120 | fn no_relro(&mut self); | |
62682a34 | 121 | fn optimize(&mut self); |
0531ce1d | 122 | fn pgo_gen(&mut self); |
74b04a01 | 123 | fn control_flow_guard(&mut self); |
f9f354fc XL |
124 | fn debuginfo(&mut self, strip: Strip); |
125 | fn no_crt_objects(&mut self); | |
62682a34 | 126 | fn no_default_libraries(&mut self); |
3157f602 | 127 | fn export_symbols(&mut self, tmpdir: &Path, crate_type: CrateType); |
c30ab7b3 | 128 | fn subsystem(&mut self, subsystem: &str); |
0531ce1d XL |
129 | fn group_start(&mut self); |
130 | fn group_end(&mut self); | |
9fa01778 | 131 | fn linker_plugin_lto(&mut self); |
f035d41b | 132 | fn add_eh_frame_header(&mut self) {} |
ba9703b0 XL |
133 | fn finalize(&mut self); |
134 | } | |
135 | ||
136 | impl dyn Linker + '_ { | |
137 | pub fn arg(&mut self, arg: impl AsRef<OsStr>) { | |
138 | self.cmd().arg(arg); | |
139 | } | |
140 | ||
141 | pub fn args(&mut self, args: impl IntoIterator<Item: AsRef<OsStr>>) { | |
142 | self.cmd().args(args); | |
143 | } | |
144 | ||
145 | pub fn take_cmd(&mut self) -> Command { | |
146 | mem::replace(self.cmd(), Command::new("")) | |
147 | } | |
62682a34 SL |
148 | } |
149 | ||
cc61c64b XL |
150 | pub struct GccLinker<'a> { |
151 | cmd: Command, | |
3157f602 | 152 | sess: &'a Session, |
cc61c64b XL |
153 | info: &'a LinkerInfo, |
154 | hinted_static: bool, // Keeps track of the current hinting mode. | |
155 | // Link as ld | |
156 | is_ld: bool, | |
a1dfa0c6 | 157 | target_cpu: &'a str, |
62682a34 SL |
158 | } |
159 | ||
cc61c64b XL |
160 | impl<'a> GccLinker<'a> { |
161 | /// Argument that must be passed *directly* to the linker | |
162 | /// | |
9fa01778 | 163 | /// These arguments need to be prepended with `-Wl`, when a GCC-style linker is used. |
cc61c64b | 164 | fn linker_arg<S>(&mut self, arg: S) -> &mut Self |
dfeec247 XL |
165 | where |
166 | S: AsRef<OsStr>, | |
cc61c64b XL |
167 | { |
168 | if !self.is_ld { | |
169 | let mut os = OsString::from("-Wl,"); | |
170 | os.push(arg.as_ref()); | |
171 | self.cmd.arg(os); | |
172 | } else { | |
173 | self.cmd.arg(arg); | |
174 | } | |
175 | self | |
176 | } | |
177 | ||
62682a34 | 178 | fn takes_hints(&self) -> bool { |
532ac7d7 XL |
179 | // Really this function only returns true if the underlying linker |
180 | // configured for a compiler is binutils `ld.bfd` and `ld.gold`. We | |
181 | // don't really have a foolproof way to detect that, so rule out some | |
182 | // platforms where currently this is guaranteed to *not* be the case: | |
183 | // | |
184 | // * On OSX they have their own linker, not binutils' | |
185 | // * For WebAssembly the only functional linker is LLD, which doesn't | |
186 | // support hint flags | |
dfeec247 | 187 | !self.sess.target.target.options.is_like_osx && self.sess.target.target.arch != "wasm32" |
62682a34 | 188 | } |
cc61c64b XL |
189 | |
190 | // Some platforms take hints about whether a library is static or dynamic. | |
191 | // For those that support this, we ensure we pass the option if the library | |
192 | // was flagged "static" (most defaults are dynamic) to ensure that if | |
193 | // libfoo.a and libfoo.so both exist that the right one is chosen. | |
194 | fn hint_static(&mut self) { | |
dfeec247 XL |
195 | if !self.takes_hints() { |
196 | return; | |
197 | } | |
cc61c64b XL |
198 | if !self.hinted_static { |
199 | self.linker_arg("-Bstatic"); | |
200 | self.hinted_static = true; | |
201 | } | |
202 | } | |
203 | ||
204 | fn hint_dynamic(&mut self) { | |
dfeec247 XL |
205 | if !self.takes_hints() { |
206 | return; | |
207 | } | |
cc61c64b XL |
208 | if self.hinted_static { |
209 | self.linker_arg("-Bdynamic"); | |
210 | self.hinted_static = false; | |
211 | } | |
212 | } | |
8faf50e0 | 213 | |
9fa01778 | 214 | fn push_linker_plugin_lto_args(&mut self, plugin_path: Option<&OsStr>) { |
8faf50e0 XL |
215 | if let Some(plugin_path) = plugin_path { |
216 | let mut arg = OsString::from("-plugin="); | |
217 | arg.push(plugin_path); | |
218 | self.linker_arg(&arg); | |
219 | } | |
220 | ||
221 | let opt_level = match self.sess.opts.optimize { | |
222 | config::OptLevel::No => "O0", | |
223 | config::OptLevel::Less => "O1", | |
224 | config::OptLevel::Default => "O2", | |
225 | config::OptLevel::Aggressive => "O3", | |
226 | config::OptLevel::Size => "Os", | |
227 | config::OptLevel::SizeMin => "Oz", | |
228 | }; | |
229 | ||
230 | self.linker_arg(&format!("-plugin-opt={}", opt_level)); | |
a1dfa0c6 XL |
231 | let target_cpu = self.target_cpu; |
232 | self.linker_arg(&format!("-plugin-opt=mcpu={}", target_cpu)); | |
8faf50e0 | 233 | } |
f9f354fc XL |
234 | |
235 | fn build_dylib(&mut self, out_filename: &Path) { | |
236 | // On mac we need to tell the linker to let this library be rpathed | |
237 | if self.sess.target.target.options.is_like_osx { | |
238 | self.cmd.arg("-dynamiclib"); | |
239 | self.linker_arg("-dylib"); | |
240 | ||
241 | // Note that the `osx_rpath_install_name` option here is a hack | |
242 | // purely to support rustbuild right now, we should get a more | |
243 | // principled solution at some point to force the compiler to pass | |
244 | // the right `-Wl,-install_name` with an `@rpath` in it. | |
245 | if self.sess.opts.cg.rpath || self.sess.opts.debugging_opts.osx_rpath_install_name { | |
246 | self.linker_arg("-install_name"); | |
247 | let mut v = OsString::from("@rpath/"); | |
248 | v.push(out_filename.file_name().unwrap()); | |
249 | self.linker_arg(&v); | |
250 | } | |
251 | } else { | |
252 | self.cmd.arg("-shared"); | |
253 | if self.sess.target.target.options.is_like_windows { | |
254 | // The output filename already contains `dll_suffix` so | |
255 | // the resulting import library will have a name in the | |
256 | // form of libfoo.dll.a | |
257 | let implib_name = | |
258 | out_filename.file_name().and_then(|file| file.to_str()).map(|file| { | |
259 | format!( | |
260 | "{}{}{}", | |
261 | self.sess.target.target.options.staticlib_prefix, | |
262 | file, | |
263 | self.sess.target.target.options.staticlib_suffix | |
264 | ) | |
265 | }); | |
266 | if let Some(implib_name) = implib_name { | |
267 | let implib = out_filename.parent().map(|dir| dir.join(&implib_name)); | |
268 | if let Some(implib) = implib { | |
3dfed10e | 269 | self.linker_arg(&format!("--out-implib={}", (*implib).to_str().unwrap())); |
f9f354fc XL |
270 | } |
271 | } | |
272 | } | |
273 | } | |
274 | } | |
62682a34 SL |
275 | } |
276 | ||
cc61c64b | 277 | impl<'a> Linker for GccLinker<'a> { |
ba9703b0 XL |
278 | fn cmd(&mut self) -> &mut Command { |
279 | &mut self.cmd | |
280 | } | |
f9f354fc XL |
281 | |
282 | fn set_output_kind(&mut self, output_kind: LinkOutputKind, out_filename: &Path) { | |
283 | match output_kind { | |
284 | LinkOutputKind::DynamicNoPicExe => { | |
285 | if !self.is_ld && self.sess.target.target.options.linker_is_gnu { | |
286 | self.cmd.arg("-no-pie"); | |
287 | } | |
288 | } | |
289 | LinkOutputKind::DynamicPicExe => { | |
290 | // `-pie` works for both gcc wrapper and ld. | |
291 | self.cmd.arg("-pie"); | |
292 | } | |
293 | LinkOutputKind::StaticNoPicExe => { | |
294 | // `-static` works for both gcc wrapper and ld. | |
295 | self.cmd.arg("-static"); | |
296 | if !self.is_ld && self.sess.target.target.options.linker_is_gnu { | |
297 | self.cmd.arg("-no-pie"); | |
298 | } | |
299 | } | |
300 | LinkOutputKind::StaticPicExe => { | |
301 | if !self.is_ld { | |
302 | // Note that combination `-static -pie` doesn't work as expected | |
303 | // for the gcc wrapper, `-static` in that case suppresses `-pie`. | |
304 | self.cmd.arg("-static-pie"); | |
305 | } else { | |
306 | // `--no-dynamic-linker` and `-z text` are not strictly necessary for producing | |
307 | // a static pie, but currently passed because gcc and clang pass them. | |
308 | // The former suppresses the `INTERP` ELF header specifying dynamic linker, | |
309 | // which is otherwise implicitly injected by ld (but not lld). | |
310 | // The latter doesn't change anything, only ensures that everything is pic. | |
311 | self.cmd.args(&["-static", "-pie", "--no-dynamic-linker", "-z", "text"]); | |
312 | } | |
313 | } | |
314 | LinkOutputKind::DynamicDylib => self.build_dylib(out_filename), | |
315 | LinkOutputKind::StaticDylib => { | |
316 | self.cmd.arg("-static"); | |
317 | self.build_dylib(out_filename); | |
318 | } | |
319 | } | |
f035d41b XL |
320 | // VxWorks compiler driver introduced `--static-crt` flag specifically for rustc, |
321 | // it switches linking for libc and similar system libraries to static without using | |
322 | // any `#[link]` attributes in the `libc` crate, see #72782 for details. | |
323 | // FIXME: Switch to using `#[link]` attributes in the `libc` crate | |
324 | // similarly to other targets. | |
325 | if self.sess.target.target.target_os == "vxworks" | |
326 | && matches!( | |
327 | output_kind, | |
328 | LinkOutputKind::StaticNoPicExe | |
329 | | LinkOutputKind::StaticPicExe | |
330 | | LinkOutputKind::StaticDylib | |
331 | ) | |
332 | { | |
333 | self.cmd.arg("--static-crt"); | |
334 | } | |
f9f354fc XL |
335 | } |
336 | ||
e1599b0c XL |
337 | fn link_dylib(&mut self, lib: Symbol) { |
338 | self.hint_dynamic(); | |
339 | self.cmd.arg(format!("-l{}", lib)); | |
340 | } | |
341 | fn link_staticlib(&mut self, lib: Symbol) { | |
342 | self.hint_static(); | |
343 | self.cmd.arg(format!("-l{}", lib)); | |
8faf50e0 | 344 | } |
dfeec247 XL |
345 | fn link_rlib(&mut self, lib: &Path) { |
346 | self.hint_static(); | |
347 | self.cmd.arg(lib); | |
348 | } | |
349 | fn include_path(&mut self, path: &Path) { | |
350 | self.cmd.arg("-L").arg(path); | |
351 | } | |
352 | fn framework_path(&mut self, path: &Path) { | |
353 | self.cmd.arg("-F").arg(path); | |
354 | } | |
355 | fn output_filename(&mut self, path: &Path) { | |
356 | self.cmd.arg("-o").arg(path); | |
357 | } | |
358 | fn add_object(&mut self, path: &Path) { | |
359 | self.cmd.arg(path); | |
360 | } | |
dfeec247 XL |
361 | fn full_relro(&mut self) { |
362 | self.linker_arg("-zrelro"); | |
363 | self.linker_arg("-znow"); | |
364 | } | |
365 | fn partial_relro(&mut self) { | |
366 | self.linker_arg("-zrelro"); | |
367 | } | |
368 | fn no_relro(&mut self) { | |
369 | self.linker_arg("-znorelro"); | |
370 | } | |
62682a34 | 371 | |
e1599b0c | 372 | fn link_rust_dylib(&mut self, lib: Symbol, _path: &Path) { |
cc61c64b | 373 | self.hint_dynamic(); |
a1dfa0c6 | 374 | self.cmd.arg(format!("-l{}", lib)); |
c1a9b12d SL |
375 | } |
376 | ||
e1599b0c | 377 | fn link_framework(&mut self, framework: Symbol) { |
cc61c64b | 378 | self.hint_dynamic(); |
e1599b0c | 379 | self.cmd.arg("-framework").sym_arg(framework); |
62682a34 SL |
380 | } |
381 | ||
cc61c64b XL |
382 | // Here we explicitly ask that the entire archive is included into the |
383 | // result artifact. For more details see #15460, but the gist is that | |
384 | // the linker will strip away any unused objects in the archive if we | |
385 | // don't otherwise explicitly reference them. This can occur for | |
386 | // libraries which are just providing bindings, libraries with generic | |
387 | // functions, etc. | |
e1599b0c | 388 | fn link_whole_staticlib(&mut self, lib: Symbol, search_path: &[PathBuf]) { |
cc61c64b | 389 | self.hint_static(); |
62682a34 SL |
390 | let target = &self.sess.target.target; |
391 | if !target.options.is_like_osx { | |
a1dfa0c6 | 392 | self.linker_arg("--whole-archive").cmd.arg(format!("-l{}", lib)); |
cc61c64b | 393 | self.linker_arg("--no-whole-archive"); |
62682a34 | 394 | } else { |
cc61c64b | 395 | // -force_load is the macOS equivalent of --whole-archive, but it |
62682a34 | 396 | // involves passing the full path to the library to link. |
8faf50e0 XL |
397 | self.linker_arg("-force_load"); |
398 | let lib = archive::find_library(lib, search_path, &self.sess); | |
399 | self.linker_arg(&lib); | |
c1a9b12d SL |
400 | } |
401 | } | |
402 | ||
403 | fn link_whole_rlib(&mut self, lib: &Path) { | |
cc61c64b | 404 | self.hint_static(); |
c1a9b12d | 405 | if self.sess.target.target.options.is_like_osx { |
8faf50e0 XL |
406 | self.linker_arg("-force_load"); |
407 | self.linker_arg(&lib); | |
c1a9b12d | 408 | } else { |
cc61c64b XL |
409 | self.linker_arg("--whole-archive").cmd.arg(lib); |
410 | self.linker_arg("--no-whole-archive"); | |
62682a34 SL |
411 | } |
412 | } | |
413 | ||
a7813a04 | 414 | fn gc_sections(&mut self, keep_metadata: bool) { |
62682a34 SL |
415 | // The dead_strip option to the linker specifies that functions and data |
416 | // unreachable by the entry point will be removed. This is quite useful | |
417 | // with Rust's compilation model of compiling libraries at a time into | |
418 | // one object file. For example, this brings hello world from 1.7MB to | |
419 | // 458K. | |
420 | // | |
421 | // Note that this is done for both executables and dynamic libraries. We | |
422 | // won't get much benefit from dylibs because LLVM will have already | |
423 | // stripped away as much as it could. This has not been seen to impact | |
424 | // link times negatively. | |
425 | // | |
426 | // -dead_strip can't be part of the pre_link_args because it's also used | |
427 | // for partial linking when using multiple codegen units (-r). So we | |
428 | // insert it here. | |
429 | if self.sess.target.target.options.is_like_osx { | |
cc61c64b | 430 | self.linker_arg("-dead_strip"); |
7453a54e | 431 | } else if self.sess.target.target.options.is_like_solaris { |
8faf50e0 | 432 | self.linker_arg("-zignore"); |
62682a34 SL |
433 | |
434 | // If we're building a dylib, we don't use --gc-sections because LLVM | |
435 | // has already done the best it can do, and we also don't want to | |
436 | // eliminate the metadata. If we're building an executable, however, | |
437 | // --gc-sections drops the size of hello world from 1.8MB to 597K, a 67% | |
438 | // reduction. | |
a7813a04 | 439 | } else if !keep_metadata { |
cc61c64b | 440 | self.linker_arg("--gc-sections"); |
62682a34 SL |
441 | } |
442 | } | |
443 | ||
444 | fn optimize(&mut self) { | |
dfeec247 XL |
445 | if !self.sess.target.target.options.linker_is_gnu { |
446 | return; | |
447 | } | |
62682a34 SL |
448 | |
449 | // GNU-style linkers support optimization with -O. GNU ld doesn't | |
450 | // need a numeric argument, but other linkers do. | |
dfeec247 XL |
451 | if self.sess.opts.optimize == config::OptLevel::Default |
452 | || self.sess.opts.optimize == config::OptLevel::Aggressive | |
453 | { | |
cc61c64b | 454 | self.linker_arg("-O1"); |
62682a34 SL |
455 | } |
456 | } | |
457 | ||
0531ce1d | 458 | fn pgo_gen(&mut self) { |
dfeec247 XL |
459 | if !self.sess.target.target.options.linker_is_gnu { |
460 | return; | |
461 | } | |
0531ce1d XL |
462 | |
463 | // If we're doing PGO generation stuff and on a GNU-like linker, use the | |
464 | // "-u" flag to properly pull in the profiler runtime bits. | |
465 | // | |
466 | // This is because LLVM otherwise won't add the needed initialization | |
467 | // for us on Linux (though the extra flag should be harmless if it | |
468 | // does). | |
469 | // | |
470 | // See https://reviews.llvm.org/D14033 and https://reviews.llvm.org/D14030. | |
471 | // | |
472 | // Though it may be worth to try to revert those changes upstream, since | |
473 | // the overhead of the initialization should be minor. | |
474 | self.cmd.arg("-u"); | |
475 | self.cmd.arg("__llvm_profile_runtime"); | |
476 | } | |
477 | ||
f035d41b | 478 | fn control_flow_guard(&mut self) {} |
74b04a01 | 479 | |
f9f354fc XL |
480 | fn debuginfo(&mut self, strip: Strip) { |
481 | match strip { | |
482 | Strip::None => {} | |
483 | Strip::Debuginfo => { | |
f035d41b XL |
484 | // MacOS linker does not support longhand argument --strip-debug |
485 | self.linker_arg("-S"); | |
a1dfa0c6 | 486 | } |
f9f354fc | 487 | Strip::Symbols => { |
f035d41b XL |
488 | // MacOS linker does not support longhand argument --strip-all |
489 | self.linker_arg("-s"); | |
f9f354fc XL |
490 | } |
491 | } | |
c1a9b12d SL |
492 | } |
493 | ||
f9f354fc | 494 | fn no_crt_objects(&mut self) { |
cc61c64b | 495 | if !self.is_ld { |
f9f354fc | 496 | self.cmd.arg("-nostartfiles"); |
cc61c64b | 497 | } |
62682a34 SL |
498 | } |
499 | ||
f9f354fc XL |
500 | fn no_default_libraries(&mut self) { |
501 | if !self.is_ld { | |
502 | self.cmd.arg("-nodefaultlibs"); | |
62682a34 SL |
503 | } |
504 | } | |
505 | ||
3157f602 | 506 | fn export_symbols(&mut self, tmpdir: &Path, crate_type: CrateType) { |
48663c56 | 507 | // Symbol visibility in object files typically takes care of this. |
dfeec247 XL |
508 | if crate_type == CrateType::Executable |
509 | && self.sess.target.target.options.override_export_symbols.is_none() | |
510 | { | |
48663c56 XL |
511 | return; |
512 | } | |
513 | ||
dc9dc135 XL |
514 | // We manually create a list of exported symbols to ensure we don't expose any more. |
515 | // The object files have far more public symbols than we actually want to export, | |
516 | // so we hide them all here. | |
a7813a04 | 517 | |
dc9dc135 | 518 | if !self.sess.target.target.options.limit_rdylib_exports { |
532ac7d7 XL |
519 | return; |
520 | } | |
521 | ||
dc9dc135 | 522 | if crate_type == CrateType::ProcMacro { |
dfeec247 | 523 | return; |
dc9dc135 XL |
524 | } |
525 | ||
3dfed10e | 526 | let is_windows = self.sess.target.target.options.is_like_windows; |
9e0c209e | 527 | let mut arg = OsString::new(); |
3dfed10e | 528 | let path = tmpdir.join(if is_windows { "list.def" } else { "list" }); |
9e0c209e | 529 | |
476ff2be SL |
530 | debug!("EXPORTED SYMBOLS:"); |
531 | ||
532 | if self.sess.target.target.options.is_like_osx { | |
533 | // Write a plain, newline-separated list of symbols | |
532ac7d7 | 534 | let res: io::Result<()> = try { |
9e0c209e | 535 | let mut f = BufWriter::new(File::create(&path)?); |
9e0c209e | 536 | for sym in self.info.exports[&crate_type].iter() { |
476ff2be SL |
537 | debug!(" _{}", sym); |
538 | writeln!(f, "_{}", sym)?; | |
9e0c209e | 539 | } |
532ac7d7 | 540 | }; |
9e0c209e | 541 | if let Err(e) = res { |
476ff2be | 542 | self.sess.fatal(&format!("failed to write lib.def file: {}", e)); |
a7813a04 | 543 | } |
3dfed10e XL |
544 | } else if is_windows { |
545 | let res: io::Result<()> = try { | |
546 | let mut f = BufWriter::new(File::create(&path)?); | |
547 | ||
548 | // .def file similar to MSVC one but without LIBRARY section | |
549 | // because LD doesn't like when it's empty | |
550 | writeln!(f, "EXPORTS")?; | |
551 | for symbol in self.info.exports[&crate_type].iter() { | |
552 | debug!(" _{}", symbol); | |
553 | writeln!(f, " {}", symbol)?; | |
554 | } | |
555 | }; | |
556 | if let Err(e) = res { | |
557 | self.sess.fatal(&format!("failed to write list.def file: {}", e)); | |
558 | } | |
a7813a04 | 559 | } else { |
476ff2be | 560 | // Write an LD version script |
532ac7d7 | 561 | let res: io::Result<()> = try { |
9e0c209e | 562 | let mut f = BufWriter::new(File::create(&path)?); |
e1599b0c XL |
563 | writeln!(f, "{{")?; |
564 | if !self.info.exports[&crate_type].is_empty() { | |
565 | writeln!(f, " global:")?; | |
566 | for sym in self.info.exports[&crate_type].iter() { | |
567 | debug!(" {};", sym); | |
568 | writeln!(f, " {};", sym)?; | |
569 | } | |
9e0c209e | 570 | } |
476ff2be | 571 | writeln!(f, "\n local:\n *;\n}};")?; |
532ac7d7 | 572 | }; |
9e0c209e | 573 | if let Err(e) = res { |
476ff2be | 574 | self.sess.fatal(&format!("failed to write version script: {}", e)); |
9e0c209e | 575 | } |
a7813a04 | 576 | } |
9e0c209e | 577 | |
476ff2be | 578 | if self.sess.target.target.options.is_like_osx { |
cc61c64b XL |
579 | if !self.is_ld { |
580 | arg.push("-Wl,") | |
581 | } | |
582 | arg.push("-exported_symbols_list,"); | |
476ff2be | 583 | } else if self.sess.target.target.options.is_like_solaris { |
cc61c64b XL |
584 | if !self.is_ld { |
585 | arg.push("-Wl,") | |
586 | } | |
587 | arg.push("-M,"); | |
476ff2be | 588 | } else { |
cc61c64b XL |
589 | if !self.is_ld { |
590 | arg.push("-Wl,") | |
591 | } | |
3dfed10e XL |
592 | // Both LD and LLD accept export list in *.def file form, there are no flags required |
593 | if !is_windows { | |
594 | arg.push("--version-script=") | |
595 | } | |
476ff2be SL |
596 | } |
597 | ||
598 | arg.push(&path); | |
a7813a04 | 599 | self.cmd.arg(arg); |
e9174d1e | 600 | } |
c30ab7b3 SL |
601 | |
602 | fn subsystem(&mut self, subsystem: &str) { | |
8faf50e0 XL |
603 | self.linker_arg("--subsystem"); |
604 | self.linker_arg(&subsystem); | |
cc61c64b XL |
605 | } |
606 | ||
ba9703b0 | 607 | fn finalize(&mut self) { |
cc61c64b | 608 | self.hint_dynamic(); // Reset to default before returning the composed command line. |
c30ab7b3 | 609 | } |
0531ce1d XL |
610 | |
611 | fn group_start(&mut self) { | |
532ac7d7 | 612 | if self.takes_hints() { |
0531ce1d XL |
613 | self.linker_arg("--start-group"); |
614 | } | |
615 | } | |
616 | ||
617 | fn group_end(&mut self) { | |
532ac7d7 | 618 | if self.takes_hints() { |
0531ce1d XL |
619 | self.linker_arg("--end-group"); |
620 | } | |
621 | } | |
94b46f34 | 622 | |
9fa01778 XL |
623 | fn linker_plugin_lto(&mut self) { |
624 | match self.sess.opts.cg.linker_plugin_lto { | |
625 | LinkerPluginLto::Disabled => { | |
94b46f34 XL |
626 | // Nothing to do |
627 | } | |
9fa01778 XL |
628 | LinkerPluginLto::LinkerPluginAuto => { |
629 | self.push_linker_plugin_lto_args(None); | |
8faf50e0 | 630 | } |
9fa01778 XL |
631 | LinkerPluginLto::LinkerPlugin(ref path) => { |
632 | self.push_linker_plugin_lto_args(Some(path.as_os_str())); | |
94b46f34 XL |
633 | } |
634 | } | |
635 | } | |
f035d41b XL |
636 | |
637 | // Add the `GNU_EH_FRAME` program header which is required to locate unwinding information. | |
638 | // Some versions of `gcc` add it implicitly, some (e.g. `musl-gcc`) don't, | |
639 | // so we just always add it. | |
640 | fn add_eh_frame_header(&mut self) { | |
f9652781 | 641 | self.linker_arg("--eh-frame-hdr"); |
f035d41b | 642 | } |
62682a34 SL |
643 | } |
644 | ||
645 | pub struct MsvcLinker<'a> { | |
cc61c64b | 646 | cmd: Command, |
3157f602 | 647 | sess: &'a Session, |
dfeec247 | 648 | info: &'a LinkerInfo, |
62682a34 SL |
649 | } |
650 | ||
651 | impl<'a> Linker for MsvcLinker<'a> { | |
ba9703b0 XL |
652 | fn cmd(&mut self) -> &mut Command { |
653 | &mut self.cmd | |
654 | } | |
f9f354fc XL |
655 | |
656 | fn set_output_kind(&mut self, output_kind: LinkOutputKind, out_filename: &Path) { | |
657 | match output_kind { | |
658 | LinkOutputKind::DynamicNoPicExe | |
659 | | LinkOutputKind::DynamicPicExe | |
660 | | LinkOutputKind::StaticNoPicExe | |
661 | | LinkOutputKind::StaticPicExe => {} | |
662 | LinkOutputKind::DynamicDylib | LinkOutputKind::StaticDylib => { | |
663 | self.cmd.arg("/DLL"); | |
664 | let mut arg: OsString = "/IMPLIB:".into(); | |
665 | arg.push(out_filename.with_extension("dll.lib")); | |
666 | self.cmd.arg(arg); | |
667 | } | |
668 | } | |
669 | } | |
670 | ||
dfeec247 XL |
671 | fn link_rlib(&mut self, lib: &Path) { |
672 | self.cmd.arg(lib); | |
673 | } | |
674 | fn add_object(&mut self, path: &Path) { | |
675 | self.cmd.arg(path); | |
676 | } | |
7453a54e | 677 | |
a7813a04 | 678 | fn gc_sections(&mut self, _keep_metadata: bool) { |
476ff2be SL |
679 | // MSVC's ICF (Identical COMDAT Folding) link optimization is |
680 | // slow for Rust and thus we disable it by default when not in | |
681 | // optimization build. | |
682 | if self.sess.opts.optimize != config::OptLevel::No { | |
683 | self.cmd.arg("/OPT:REF,ICF"); | |
684 | } else { | |
685 | // It is necessary to specify NOICF here, because /OPT:REF | |
686 | // implies ICF by default. | |
687 | self.cmd.arg("/OPT:REF,NOICF"); | |
688 | } | |
a7813a04 | 689 | } |
62682a34 | 690 | |
e1599b0c | 691 | fn link_dylib(&mut self, lib: Symbol) { |
62682a34 SL |
692 | self.cmd.arg(&format!("{}.lib", lib)); |
693 | } | |
c1a9b12d | 694 | |
e1599b0c | 695 | fn link_rust_dylib(&mut self, lib: Symbol, path: &Path) { |
c1a9b12d SL |
696 | // When producing a dll, the MSVC linker may not actually emit a |
697 | // `foo.lib` file if the dll doesn't actually export any symbols, so we | |
698 | // check to see if the file is there and just omit linking to it if it's | |
699 | // not present. | |
7453a54e | 700 | let name = format!("{}.dll.lib", lib); |
c1a9b12d SL |
701 | if fs::metadata(&path.join(&name)).is_ok() { |
702 | self.cmd.arg(name); | |
703 | } | |
704 | } | |
705 | ||
e1599b0c | 706 | fn link_staticlib(&mut self, lib: Symbol) { |
62682a34 SL |
707 | self.cmd.arg(&format!("{}.lib", lib)); |
708 | } | |
709 | ||
3b2f2976 XL |
710 | fn full_relro(&mut self) { |
711 | // noop | |
712 | } | |
713 | ||
0531ce1d XL |
714 | fn partial_relro(&mut self) { |
715 | // noop | |
716 | } | |
717 | ||
718 | fn no_relro(&mut self) { | |
719 | // noop | |
720 | } | |
721 | ||
f9f354fc XL |
722 | fn no_crt_objects(&mut self) { |
723 | // noop | |
724 | } | |
725 | ||
62682a34 | 726 | fn no_default_libraries(&mut self) { |
ba9703b0 | 727 | self.cmd.arg("/NODEFAULTLIB"); |
62682a34 SL |
728 | } |
729 | ||
730 | fn include_path(&mut self, path: &Path) { | |
731 | let mut arg = OsString::from("/LIBPATH:"); | |
732 | arg.push(path); | |
733 | self.cmd.arg(&arg); | |
734 | } | |
735 | ||
736 | fn output_filename(&mut self, path: &Path) { | |
737 | let mut arg = OsString::from("/OUT:"); | |
738 | arg.push(path); | |
739 | self.cmd.arg(&arg); | |
740 | } | |
741 | ||
742 | fn framework_path(&mut self, _path: &Path) { | |
54a0048b | 743 | bug!("frameworks are not supported on windows") |
62682a34 | 744 | } |
e1599b0c | 745 | fn link_framework(&mut self, _framework: Symbol) { |
54a0048b | 746 | bug!("frameworks are not supported on windows") |
62682a34 SL |
747 | } |
748 | ||
e1599b0c | 749 | fn link_whole_staticlib(&mut self, lib: Symbol, _search_path: &[PathBuf]) { |
62682a34 | 750 | self.link_staticlib(lib); |
f035d41b | 751 | self.cmd.arg(format!("/WHOLEARCHIVE:{}.lib", lib)); |
62682a34 | 752 | } |
c1a9b12d | 753 | fn link_whole_rlib(&mut self, path: &Path) { |
c1a9b12d | 754 | self.link_rlib(path); |
f035d41b XL |
755 | let mut arg = OsString::from("/WHOLEARCHIVE:"); |
756 | arg.push(path); | |
757 | self.cmd.arg(arg); | |
c1a9b12d | 758 | } |
62682a34 SL |
759 | fn optimize(&mut self) { |
760 | // Needs more investigation of `/OPT` arguments | |
761 | } | |
c1a9b12d | 762 | |
0531ce1d XL |
763 | fn pgo_gen(&mut self) { |
764 | // Nothing needed here. | |
765 | } | |
766 | ||
74b04a01 XL |
767 | fn control_flow_guard(&mut self) { |
768 | self.cmd.arg("/guard:cf"); | |
769 | } | |
770 | ||
f9f354fc XL |
771 | fn debuginfo(&mut self, strip: Strip) { |
772 | match strip { | |
773 | Strip::None => { | |
774 | // This will cause the Microsoft linker to generate a PDB file | |
775 | // from the CodeView line tables in the object files. | |
776 | self.cmd.arg("/DEBUG"); | |
777 | ||
778 | // This will cause the Microsoft linker to embed .natvis info into the PDB file | |
779 | let natvis_dir_path = self.sess.sysroot.join("lib\\rustlib\\etc"); | |
780 | if let Ok(natvis_dir) = fs::read_dir(&natvis_dir_path) { | |
781 | for entry in natvis_dir { | |
782 | match entry { | |
783 | Ok(entry) => { | |
784 | let path = entry.path(); | |
785 | if path.extension() == Some("natvis".as_ref()) { | |
786 | let mut arg = OsString::from("/NATVIS:"); | |
787 | arg.push(path); | |
788 | self.cmd.arg(arg); | |
789 | } | |
790 | } | |
791 | Err(err) => { | |
792 | self.sess | |
793 | .warn(&format!("error enumerating natvis directory: {}", err)); | |
794 | } | |
3b2f2976 | 795 | } |
dfeec247 | 796 | } |
3b2f2976 XL |
797 | } |
798 | } | |
f9f354fc XL |
799 | Strip::Debuginfo | Strip::Symbols => { |
800 | self.cmd.arg("/DEBUG:NONE"); | |
801 | } | |
3b2f2976 | 802 | } |
c1a9b12d SL |
803 | } |
804 | ||
e9174d1e SL |
805 | // Currently the compiler doesn't use `dllexport` (an LLVM attribute) to |
806 | // export symbols from a dynamic library. When building a dynamic library, | |
807 | // however, we're going to want some symbols exported, so this function | |
808 | // generates a DEF file which lists all the symbols. | |
809 | // | |
810 | // The linker will read this `*.def` file and export all the symbols from | |
811 | // the dynamic library. Note that this is not as simple as just exporting | |
94b46f34 | 812 | // all the symbols in the current crate (as specified by `codegen.reachable`) |
e9174d1e SL |
813 | // but rather we also need to possibly export the symbols of upstream |
814 | // crates. Upstream rlibs may be linked statically to this dynamic library, | |
815 | // in which case they may continue to transitively be used and hence need | |
816 | // their symbols exported. | |
dfeec247 | 817 | fn export_symbols(&mut self, tmpdir: &Path, crate_type: CrateType) { |
48663c56 XL |
818 | // Symbol visibility takes care of this typically |
819 | if crate_type == CrateType::Executable { | |
820 | return; | |
821 | } | |
822 | ||
e9174d1e | 823 | let path = tmpdir.join("lib.def"); |
532ac7d7 | 824 | let res: io::Result<()> = try { |
54a0048b | 825 | let mut f = BufWriter::new(File::create(&path)?); |
e9174d1e SL |
826 | |
827 | // Start off with the standard module name header and then go | |
828 | // straight to exports. | |
54a0048b SL |
829 | writeln!(f, "LIBRARY")?; |
830 | writeln!(f, "EXPORTS")?; | |
9e0c209e | 831 | for symbol in self.info.exports[&crate_type].iter() { |
8bb4bdeb | 832 | debug!(" _{}", symbol); |
3157f602 | 833 | writeln!(f, " {}", symbol)?; |
e9174d1e | 834 | } |
532ac7d7 | 835 | }; |
e9174d1e | 836 | if let Err(e) = res { |
3157f602 | 837 | self.sess.fatal(&format!("failed to write lib.def file: {}", e)); |
e9174d1e SL |
838 | } |
839 | let mut arg = OsString::from("/DEF:"); | |
840 | arg.push(path); | |
841 | self.cmd.arg(&arg); | |
842 | } | |
c30ab7b3 SL |
843 | |
844 | fn subsystem(&mut self, subsystem: &str) { | |
845 | // Note that previous passes of the compiler validated this subsystem, | |
846 | // so we just blindly pass it to the linker. | |
847 | self.cmd.arg(&format!("/SUBSYSTEM:{}", subsystem)); | |
848 | ||
849 | // Windows has two subsystems we're interested in right now, the console | |
850 | // and windows subsystems. These both implicitly have different entry | |
851 | // points (starting symbols). The console entry point starts with | |
852 | // `mainCRTStartup` and the windows entry point starts with | |
853 | // `WinMainCRTStartup`. These entry points, defined in system libraries, | |
854 | // will then later probe for either `main` or `WinMain`, respectively to | |
855 | // start the application. | |
856 | // | |
857 | // In Rust we just always generate a `main` function so we want control | |
858 | // to always start there, so we force the entry point on the windows | |
859 | // subsystem to be `mainCRTStartup` to get everything booted up | |
860 | // correctly. | |
861 | // | |
862 | // For more information see RFC #1665 | |
863 | if subsystem == "windows" { | |
864 | self.cmd.arg("/ENTRY:mainCRTStartup"); | |
865 | } | |
866 | } | |
cc61c64b | 867 | |
ba9703b0 | 868 | fn finalize(&mut self) {} |
0531ce1d XL |
869 | |
870 | // MSVC doesn't need group indicators | |
871 | fn group_start(&mut self) {} | |
872 | fn group_end(&mut self) {} | |
94b46f34 | 873 | |
9fa01778 | 874 | fn linker_plugin_lto(&mut self) { |
94b46f34 XL |
875 | // Do nothing |
876 | } | |
62682a34 | 877 | } |
a7813a04 | 878 | |
8bb4bdeb | 879 | pub struct EmLinker<'a> { |
cc61c64b | 880 | cmd: Command, |
8bb4bdeb | 881 | sess: &'a Session, |
dfeec247 | 882 | info: &'a LinkerInfo, |
8bb4bdeb XL |
883 | } |
884 | ||
885 | impl<'a> Linker for EmLinker<'a> { | |
ba9703b0 XL |
886 | fn cmd(&mut self) -> &mut Command { |
887 | &mut self.cmd | |
888 | } | |
f9f354fc XL |
889 | |
890 | fn set_output_kind(&mut self, _output_kind: LinkOutputKind, _out_filename: &Path) {} | |
891 | ||
8bb4bdeb XL |
892 | fn include_path(&mut self, path: &Path) { |
893 | self.cmd.arg("-L").arg(path); | |
894 | } | |
895 | ||
e1599b0c XL |
896 | fn link_staticlib(&mut self, lib: Symbol) { |
897 | self.cmd.arg("-l").sym_arg(lib); | |
8bb4bdeb XL |
898 | } |
899 | ||
900 | fn output_filename(&mut self, path: &Path) { | |
901 | self.cmd.arg("-o").arg(path); | |
902 | } | |
903 | ||
904 | fn add_object(&mut self, path: &Path) { | |
905 | self.cmd.arg(path); | |
906 | } | |
907 | ||
e1599b0c | 908 | fn link_dylib(&mut self, lib: Symbol) { |
8bb4bdeb XL |
909 | // Emscripten always links statically |
910 | self.link_staticlib(lib); | |
911 | } | |
912 | ||
e1599b0c | 913 | fn link_whole_staticlib(&mut self, lib: Symbol, _search_path: &[PathBuf]) { |
8bb4bdeb XL |
914 | // not supported? |
915 | self.link_staticlib(lib); | |
916 | } | |
917 | ||
918 | fn link_whole_rlib(&mut self, lib: &Path) { | |
919 | // not supported? | |
920 | self.link_rlib(lib); | |
921 | } | |
922 | ||
e1599b0c | 923 | fn link_rust_dylib(&mut self, lib: Symbol, _path: &Path) { |
8bb4bdeb XL |
924 | self.link_dylib(lib); |
925 | } | |
926 | ||
927 | fn link_rlib(&mut self, lib: &Path) { | |
928 | self.add_object(lib); | |
929 | } | |
930 | ||
3b2f2976 XL |
931 | fn full_relro(&mut self) { |
932 | // noop | |
933 | } | |
934 | ||
0531ce1d XL |
935 | fn partial_relro(&mut self) { |
936 | // noop | |
937 | } | |
938 | ||
939 | fn no_relro(&mut self) { | |
940 | // noop | |
941 | } | |
942 | ||
8bb4bdeb XL |
943 | fn framework_path(&mut self, _path: &Path) { |
944 | bug!("frameworks are not supported on Emscripten") | |
945 | } | |
946 | ||
e1599b0c | 947 | fn link_framework(&mut self, _framework: Symbol) { |
8bb4bdeb XL |
948 | bug!("frameworks are not supported on Emscripten") |
949 | } | |
950 | ||
951 | fn gc_sections(&mut self, _keep_metadata: bool) { | |
952 | // noop | |
953 | } | |
954 | ||
955 | fn optimize(&mut self) { | |
956 | // Emscripten performs own optimizations | |
957 | self.cmd.arg(match self.sess.opts.optimize { | |
958 | OptLevel::No => "-O0", | |
959 | OptLevel::Less => "-O1", | |
960 | OptLevel::Default => "-O2", | |
961 | OptLevel::Aggressive => "-O3", | |
962 | OptLevel::Size => "-Os", | |
dfeec247 | 963 | OptLevel::SizeMin => "-Oz", |
8bb4bdeb XL |
964 | }); |
965 | // Unusable until https://github.com/rust-lang/rust/issues/38454 is resolved | |
966 | self.cmd.args(&["--memory-init-file", "0"]); | |
967 | } | |
968 | ||
0531ce1d XL |
969 | fn pgo_gen(&mut self) { |
970 | // noop, but maybe we need something like the gnu linker? | |
971 | } | |
972 | ||
f035d41b | 973 | fn control_flow_guard(&mut self) {} |
74b04a01 | 974 | |
f9f354fc | 975 | fn debuginfo(&mut self, _strip: Strip) { |
8bb4bdeb XL |
976 | // Preserve names or generate source maps depending on debug info |
977 | self.cmd.arg(match self.sess.opts.debuginfo { | |
b7449926 XL |
978 | DebugInfo::None => "-g0", |
979 | DebugInfo::Limited => "-g3", | |
dfeec247 | 980 | DebugInfo::Full => "-g4", |
8bb4bdeb XL |
981 | }); |
982 | } | |
983 | ||
f9f354fc XL |
984 | fn no_crt_objects(&mut self) {} |
985 | ||
8bb4bdeb XL |
986 | fn no_default_libraries(&mut self) { |
987 | self.cmd.args(&["-s", "DEFAULT_LIBRARY_FUNCS_TO_INCLUDE=[]"]); | |
988 | } | |
989 | ||
8bb4bdeb XL |
990 | fn export_symbols(&mut self, _tmpdir: &Path, crate_type: CrateType) { |
991 | let symbols = &self.info.exports[&crate_type]; | |
992 | ||
993 | debug!("EXPORTED SYMBOLS:"); | |
994 | ||
995 | self.cmd.arg("-s"); | |
996 | ||
997 | let mut arg = OsString::from("EXPORTED_FUNCTIONS="); | |
998 | let mut encoded = String::new(); | |
999 | ||
1000 | { | |
1001 | let mut encoder = json::Encoder::new(&mut encoded); | |
1002 | let res = encoder.emit_seq(symbols.len(), |encoder| { | |
1003 | for (i, sym) in symbols.iter().enumerate() { | |
dfeec247 | 1004 | encoder.emit_seq_elt(i, |encoder| encoder.emit_str(&("_".to_owned() + sym)))?; |
8bb4bdeb XL |
1005 | } |
1006 | Ok(()) | |
1007 | }); | |
1008 | if let Err(e) = res { | |
1009 | self.sess.fatal(&format!("failed to encode exported symbols: {}", e)); | |
1010 | } | |
1011 | } | |
1012 | debug!("{}", encoded); | |
1013 | arg.push(encoded); | |
1014 | ||
1015 | self.cmd.arg(arg); | |
1016 | } | |
1017 | ||
1018 | fn subsystem(&mut self, _subsystem: &str) { | |
1019 | // noop | |
1020 | } | |
cc61c64b | 1021 | |
ba9703b0 | 1022 | fn finalize(&mut self) {} |
0531ce1d XL |
1023 | |
1024 | // Appears not necessary on Emscripten | |
1025 | fn group_start(&mut self) {} | |
1026 | fn group_end(&mut self) {} | |
94b46f34 | 1027 | |
9fa01778 | 1028 | fn linker_plugin_lto(&mut self) { |
94b46f34 XL |
1029 | // Do nothing |
1030 | } | |
8bb4bdeb XL |
1031 | } |
1032 | ||
8faf50e0 | 1033 | pub struct WasmLd<'a> { |
0531ce1d | 1034 | cmd: Command, |
8faf50e0 | 1035 | sess: &'a Session, |
0bf4aa26 | 1036 | info: &'a LinkerInfo, |
0531ce1d XL |
1037 | } |
1038 | ||
0731742a | 1039 | impl<'a> WasmLd<'a> { |
416331ca XL |
1040 | fn new(mut cmd: Command, sess: &'a Session, info: &'a LinkerInfo) -> WasmLd<'a> { |
1041 | // If the atomics feature is enabled for wasm then we need a whole bunch | |
1042 | // of flags: | |
1043 | // | |
1044 | // * `--shared-memory` - the link won't even succeed without this, flags | |
1045 | // the one linear memory as `shared` | |
1046 | // | |
1047 | // * `--max-memory=1G` - when specifying a shared memory this must also | |
1048 | // be specified. We conservatively choose 1GB but users should be able | |
1049 | // to override this with `-C link-arg`. | |
1050 | // | |
1051 | // * `--import-memory` - it doesn't make much sense for memory to be | |
1052 | // exported in a threaded module because typically you're | |
1053 | // sharing memory and instantiating the module multiple times. As a | |
1054 | // result if it were exported then we'd just have no sharing. | |
1055 | // | |
416331ca XL |
1056 | // * `--export=__wasm_init_memory` - when using `--passive-segments` the |
1057 | // linker will synthesize this function, and so we need to make sure | |
1058 | // that our usage of `--export` below won't accidentally cause this | |
1059 | // function to get deleted. | |
1060 | // | |
1061 | // * `--export=*tls*` - when `#[thread_local]` symbols are used these | |
1062 | // symbols are how the TLS segments are initialized and configured. | |
f035d41b | 1063 | if sess.target_features.contains(&sym::atomics) { |
416331ca XL |
1064 | cmd.arg("--shared-memory"); |
1065 | cmd.arg("--max-memory=1073741824"); | |
1066 | cmd.arg("--import-memory"); | |
416331ca XL |
1067 | cmd.arg("--export=__wasm_init_memory"); |
1068 | cmd.arg("--export=__wasm_init_tls"); | |
1069 | cmd.arg("--export=__tls_size"); | |
1070 | cmd.arg("--export=__tls_align"); | |
1071 | cmd.arg("--export=__tls_base"); | |
1072 | } | |
0731742a XL |
1073 | WasmLd { cmd, sess, info } |
1074 | } | |
1075 | } | |
1076 | ||
8faf50e0 | 1077 | impl<'a> Linker for WasmLd<'a> { |
ba9703b0 XL |
1078 | fn cmd(&mut self) -> &mut Command { |
1079 | &mut self.cmd | |
1080 | } | |
1081 | ||
f9f354fc XL |
1082 | fn set_output_kind(&mut self, output_kind: LinkOutputKind, _out_filename: &Path) { |
1083 | match output_kind { | |
1084 | LinkOutputKind::DynamicNoPicExe | |
1085 | | LinkOutputKind::DynamicPicExe | |
1086 | | LinkOutputKind::StaticNoPicExe | |
1087 | | LinkOutputKind::StaticPicExe => {} | |
1088 | LinkOutputKind::DynamicDylib | LinkOutputKind::StaticDylib => { | |
1089 | self.cmd.arg("--no-entry"); | |
1090 | } | |
1091 | } | |
1092 | } | |
1093 | ||
e1599b0c XL |
1094 | fn link_dylib(&mut self, lib: Symbol) { |
1095 | self.cmd.arg("-l").sym_arg(lib); | |
0531ce1d XL |
1096 | } |
1097 | ||
e1599b0c XL |
1098 | fn link_staticlib(&mut self, lib: Symbol) { |
1099 | self.cmd.arg("-l").sym_arg(lib); | |
0531ce1d XL |
1100 | } |
1101 | ||
1102 | fn link_rlib(&mut self, lib: &Path) { | |
1103 | self.cmd.arg(lib); | |
1104 | } | |
1105 | ||
1106 | fn include_path(&mut self, path: &Path) { | |
1107 | self.cmd.arg("-L").arg(path); | |
1108 | } | |
1109 | ||
1110 | fn framework_path(&mut self, _path: &Path) { | |
1111 | panic!("frameworks not supported") | |
1112 | } | |
1113 | ||
1114 | fn output_filename(&mut self, path: &Path) { | |
1115 | self.cmd.arg("-o").arg(path); | |
1116 | } | |
1117 | ||
1118 | fn add_object(&mut self, path: &Path) { | |
1119 | self.cmd.arg(path); | |
1120 | } | |
1121 | ||
dfeec247 | 1122 | fn full_relro(&mut self) {} |
0531ce1d | 1123 | |
dfeec247 | 1124 | fn partial_relro(&mut self) {} |
0531ce1d | 1125 | |
dfeec247 | 1126 | fn no_relro(&mut self) {} |
0531ce1d | 1127 | |
e1599b0c XL |
1128 | fn link_rust_dylib(&mut self, lib: Symbol, _path: &Path) { |
1129 | self.cmd.arg("-l").sym_arg(lib); | |
0531ce1d XL |
1130 | } |
1131 | ||
e1599b0c | 1132 | fn link_framework(&mut self, _framework: Symbol) { |
0531ce1d XL |
1133 | panic!("frameworks not supported") |
1134 | } | |
1135 | ||
e1599b0c XL |
1136 | fn link_whole_staticlib(&mut self, lib: Symbol, _search_path: &[PathBuf]) { |
1137 | self.cmd.arg("-l").sym_arg(lib); | |
0531ce1d XL |
1138 | } |
1139 | ||
1140 | fn link_whole_rlib(&mut self, lib: &Path) { | |
1141 | self.cmd.arg(lib); | |
1142 | } | |
1143 | ||
1144 | fn gc_sections(&mut self, _keep_metadata: bool) { | |
8faf50e0 | 1145 | self.cmd.arg("--gc-sections"); |
0531ce1d XL |
1146 | } |
1147 | ||
1148 | fn optimize(&mut self) { | |
8faf50e0 XL |
1149 | self.cmd.arg(match self.sess.opts.optimize { |
1150 | OptLevel::No => "-O0", | |
1151 | OptLevel::Less => "-O1", | |
1152 | OptLevel::Default => "-O2", | |
1153 | OptLevel::Aggressive => "-O3", | |
1154 | // Currently LLD doesn't support `Os` and `Oz`, so pass through `O2` | |
1155 | // instead. | |
1156 | OptLevel::Size => "-O2", | |
dfeec247 | 1157 | OptLevel::SizeMin => "-O2", |
8faf50e0 | 1158 | }); |
0531ce1d XL |
1159 | } |
1160 | ||
dfeec247 | 1161 | fn pgo_gen(&mut self) {} |
0531ce1d | 1162 | |
f9f354fc XL |
1163 | fn debuginfo(&mut self, strip: Strip) { |
1164 | match strip { | |
1165 | Strip::None => {} | |
1166 | Strip::Debuginfo => { | |
1167 | self.cmd.arg("--strip-debug"); | |
1168 | } | |
1169 | Strip::Symbols => { | |
1170 | self.cmd.arg("--strip-all"); | |
1171 | } | |
1172 | } | |
1173 | } | |
0531ce1d | 1174 | |
f035d41b | 1175 | fn control_flow_guard(&mut self) {} |
74b04a01 | 1176 | |
f9f354fc | 1177 | fn no_crt_objects(&mut self) {} |
0531ce1d | 1178 | |
f9f354fc | 1179 | fn no_default_libraries(&mut self) {} |
0531ce1d | 1180 | |
0bf4aa26 XL |
1181 | fn export_symbols(&mut self, _tmpdir: &Path, crate_type: CrateType) { |
1182 | for sym in self.info.exports[&crate_type].iter() { | |
1183 | self.cmd.arg("--export").arg(&sym); | |
1184 | } | |
416331ca | 1185 | |
f035d41b XL |
1186 | // LLD will hide these otherwise-internal symbols since it only exports |
1187 | // symbols explicity passed via the `--export` flags above and hides all | |
1188 | // others. Various bits and pieces of tooling use this, so be sure these | |
1189 | // symbols make their way out of the linker as well. | |
416331ca XL |
1190 | self.cmd.arg("--export=__heap_base"); |
1191 | self.cmd.arg("--export=__data_end"); | |
0531ce1d XL |
1192 | } |
1193 | ||
dfeec247 | 1194 | fn subsystem(&mut self, _subsystem: &str) {} |
0531ce1d | 1195 | |
ba9703b0 | 1196 | fn finalize(&mut self) {} |
0531ce1d XL |
1197 | |
1198 | // Not needed for now with LLD | |
1199 | fn group_start(&mut self) {} | |
1200 | fn group_end(&mut self) {} | |
94b46f34 | 1201 | |
9fa01778 | 1202 | fn linker_plugin_lto(&mut self) { |
94b46f34 XL |
1203 | // Do nothing for now |
1204 | } | |
0531ce1d | 1205 | } |
a1dfa0c6 | 1206 | |
dc9dc135 | 1207 | fn exported_symbols(tcx: TyCtxt<'_>, crate_type: CrateType) -> Vec<String> { |
a1dfa0c6 | 1208 | if let Some(ref exports) = tcx.sess.target.target.options.override_export_symbols { |
dfeec247 | 1209 | return exports.clone(); |
a1dfa0c6 XL |
1210 | } |
1211 | ||
1212 | let mut symbols = Vec::new(); | |
1213 | ||
1214 | let export_threshold = symbol_export::crates_export_threshold(&[crate_type]); | |
1215 | for &(symbol, level) in tcx.exported_symbols(LOCAL_CRATE).iter() { | |
1216 | if level.is_below_threshold(export_threshold) { | |
dfeec247 XL |
1217 | symbols.push(symbol_export::symbol_name_for_instance_in_crate( |
1218 | tcx, | |
1219 | symbol, | |
1220 | LOCAL_CRATE, | |
1221 | )); | |
a1dfa0c6 XL |
1222 | } |
1223 | } | |
1224 | ||
e74abb32 | 1225 | let formats = tcx.dependency_formats(LOCAL_CRATE); |
f9f354fc | 1226 | let deps = formats.iter().find_map(|(t, list)| (*t == crate_type).then_some(list)).unwrap(); |
a1dfa0c6 | 1227 | |
e74abb32 | 1228 | for (index, dep_format) in deps.iter().enumerate() { |
a1dfa0c6 XL |
1229 | let cnum = CrateNum::new(index + 1); |
1230 | // For each dependency that we are linking to statically ... | |
1231 | if *dep_format == Linkage::Static { | |
1232 | // ... we add its symbol list to our export list. | |
1233 | for &(symbol, level) in tcx.exported_symbols(cnum).iter() { | |
e74abb32 XL |
1234 | if !level.is_below_threshold(export_threshold) { |
1235 | continue; | |
a1dfa0c6 | 1236 | } |
e74abb32 | 1237 | |
dfeec247 | 1238 | symbols.push(symbol_export::symbol_name_for_instance_in_crate(tcx, symbol, cnum)); |
a1dfa0c6 XL |
1239 | } |
1240 | } | |
1241 | } | |
1242 | ||
1243 | symbols | |
1244 | } | |
9fa01778 XL |
1245 | |
1246 | /// Much simplified and explicit CLI for the NVPTX linker. The linker operates | |
1247 | /// with bitcode and uses LLVM backend to generate a PTX assembly. | |
1248 | pub struct PtxLinker<'a> { | |
1249 | cmd: Command, | |
1250 | sess: &'a Session, | |
1251 | } | |
1252 | ||
1253 | impl<'a> Linker for PtxLinker<'a> { | |
ba9703b0 XL |
1254 | fn cmd(&mut self) -> &mut Command { |
1255 | &mut self.cmd | |
1256 | } | |
1257 | ||
f9f354fc XL |
1258 | fn set_output_kind(&mut self, _output_kind: LinkOutputKind, _out_filename: &Path) {} |
1259 | ||
9fa01778 XL |
1260 | fn link_rlib(&mut self, path: &Path) { |
1261 | self.cmd.arg("--rlib").arg(path); | |
1262 | } | |
1263 | ||
1264 | fn link_whole_rlib(&mut self, path: &Path) { | |
1265 | self.cmd.arg("--rlib").arg(path); | |
1266 | } | |
1267 | ||
1268 | fn include_path(&mut self, path: &Path) { | |
1269 | self.cmd.arg("-L").arg(path); | |
1270 | } | |
1271 | ||
f9f354fc | 1272 | fn debuginfo(&mut self, _strip: Strip) { |
9fa01778 XL |
1273 | self.cmd.arg("--debug"); |
1274 | } | |
1275 | ||
1276 | fn add_object(&mut self, path: &Path) { | |
1277 | self.cmd.arg("--bitcode").arg(path); | |
1278 | } | |
1279 | ||
9fa01778 XL |
1280 | fn optimize(&mut self) { |
1281 | match self.sess.lto() { | |
1282 | Lto::Thin | Lto::Fat | Lto::ThinLocal => { | |
1283 | self.cmd.arg("-Olto"); | |
dfeec247 | 1284 | } |
9fa01778 | 1285 | |
dfeec247 | 1286 | Lto::No => {} |
9fa01778 XL |
1287 | }; |
1288 | } | |
1289 | ||
1290 | fn output_filename(&mut self, path: &Path) { | |
1291 | self.cmd.arg("-o").arg(path); | |
1292 | } | |
1293 | ||
ba9703b0 | 1294 | fn finalize(&mut self) { |
9fa01778 XL |
1295 | // Provide the linker with fallback to internal `target-cpu`. |
1296 | self.cmd.arg("--fallback-arch").arg(match self.sess.opts.cg.target_cpu { | |
1297 | Some(ref s) => s, | |
dfeec247 | 1298 | None => &self.sess.target.target.options.cpu, |
9fa01778 | 1299 | }); |
9fa01778 XL |
1300 | } |
1301 | ||
e1599b0c | 1302 | fn link_dylib(&mut self, _lib: Symbol) { |
9fa01778 XL |
1303 | panic!("external dylibs not supported") |
1304 | } | |
1305 | ||
e1599b0c | 1306 | fn link_rust_dylib(&mut self, _lib: Symbol, _path: &Path) { |
9fa01778 XL |
1307 | panic!("external dylibs not supported") |
1308 | } | |
1309 | ||
e1599b0c | 1310 | fn link_staticlib(&mut self, _lib: Symbol) { |
9fa01778 XL |
1311 | panic!("staticlibs not supported") |
1312 | } | |
1313 | ||
e1599b0c | 1314 | fn link_whole_staticlib(&mut self, _lib: Symbol, _search_path: &[PathBuf]) { |
9fa01778 XL |
1315 | panic!("staticlibs not supported") |
1316 | } | |
1317 | ||
1318 | fn framework_path(&mut self, _path: &Path) { | |
1319 | panic!("frameworks not supported") | |
1320 | } | |
1321 | ||
e1599b0c | 1322 | fn link_framework(&mut self, _framework: Symbol) { |
9fa01778 XL |
1323 | panic!("frameworks not supported") |
1324 | } | |
1325 | ||
dfeec247 | 1326 | fn full_relro(&mut self) {} |
9fa01778 | 1327 | |
dfeec247 | 1328 | fn partial_relro(&mut self) {} |
9fa01778 | 1329 | |
dfeec247 | 1330 | fn no_relro(&mut self) {} |
9fa01778 | 1331 | |
dfeec247 | 1332 | fn gc_sections(&mut self, _keep_metadata: bool) {} |
9fa01778 | 1333 | |
dfeec247 | 1334 | fn pgo_gen(&mut self) {} |
9fa01778 | 1335 | |
f9f354fc XL |
1336 | fn no_crt_objects(&mut self) {} |
1337 | ||
dfeec247 | 1338 | fn no_default_libraries(&mut self) {} |
9fa01778 | 1339 | |
f035d41b | 1340 | fn control_flow_guard(&mut self) {} |
74b04a01 | 1341 | |
dfeec247 | 1342 | fn export_symbols(&mut self, _tmpdir: &Path, _crate_type: CrateType) {} |
9fa01778 | 1343 | |
dfeec247 | 1344 | fn subsystem(&mut self, _subsystem: &str) {} |
9fa01778 | 1345 | |
dfeec247 | 1346 | fn group_start(&mut self) {} |
9fa01778 | 1347 | |
dfeec247 | 1348 | fn group_end(&mut self) {} |
9fa01778 | 1349 | |
dfeec247 | 1350 | fn linker_plugin_lto(&mut self) {} |
9fa01778 | 1351 | } |