| use std::ffi::{OsStr, OsString}; |
| use std::fs::{self, File}; |
| use std::io::prelude::*; |
| use std::path::{Path, PathBuf}; |
| use std::{env, io, iter, mem, str}; |
| |
| use cc::windows_registry; |
| use rustc_hir::def_id::{CrateNum, LOCAL_CRATE}; |
| use rustc_metadata::{ |
| find_native_static_library, try_find_native_dynamic_library, try_find_native_static_library, |
| }; |
| use rustc_middle::bug; |
| use rustc_middle::middle::dependency_format::Linkage; |
| use rustc_middle::middle::exported_symbols; |
| use rustc_middle::middle::exported_symbols::{ExportedSymbol, SymbolExportInfo, SymbolExportKind}; |
| use rustc_middle::ty::TyCtxt; |
| use rustc_session::Session; |
| use rustc_session::config::{self, CrateType, DebugInfo, LinkerPluginLto, Lto, OptLevel, Strip}; |
| use rustc_span::symbol::sym; |
| use rustc_target::spec::{Cc, LinkOutputKind, LinkerFlavor, Lld}; |
| use tracing::{debug, warn}; |
| |
| use super::command::Command; |
| use super::symbol_export; |
| use crate::errors; |
| |
| /// Disables non-English messages from localized linkers. |
| /// Such messages may cause issues with text encoding on Windows (#35785) |
| /// and prevent inspection of linker output in case of errors, which we occasionally do. |
| /// This should be acceptable because other messages from rustc are in English anyway, |
| /// and may also be desirable to improve searchability of the linker diagnostics. |
| pub(crate) fn disable_localization(linker: &mut Command) { |
| // No harm in setting both env vars simultaneously. |
| // Unix-style linkers. |
| linker.env("LC_ALL", "C"); |
| // MSVC's `link.exe`. |
| linker.env("VSLANG", "1033"); |
| } |
| |
| /// The third parameter is for env vars, used on windows to set up the |
| /// path for MSVC to find its DLLs, and gcc to find its bundled |
| /// toolchain |
| pub(crate) fn get_linker<'a>( |
| sess: &'a Session, |
| linker: &Path, |
| flavor: LinkerFlavor, |
| self_contained: bool, |
| target_cpu: &'a str, |
| ) -> Box<dyn Linker + 'a> { |
| let msvc_tool = windows_registry::find_tool(sess.opts.target_triple.triple(), "link.exe"); |
| |
| // If our linker looks like a batch script on Windows then to execute this |
| // we'll need to spawn `cmd` explicitly. This is primarily done to handle |
| // emscripten where the linker is `emcc.bat` and needs to be spawned as |
| // `cmd /c emcc.bat ...`. |
| // |
| // This worked historically but is needed manually since #42436 (regression |
| // was tagged as #42791) and some more info can be found on #44443 for |
| // emscripten itself. |
| let mut cmd = match linker.to_str() { |
| Some(linker) if cfg!(windows) && linker.ends_with(".bat") => Command::bat_script(linker), |
| _ => match flavor { |
| LinkerFlavor::Gnu(Cc::No, Lld::Yes) |
| | LinkerFlavor::Darwin(Cc::No, Lld::Yes) |
| | LinkerFlavor::WasmLld(Cc::No) |
| | LinkerFlavor::Msvc(Lld::Yes) => Command::lld(linker, flavor.lld_flavor()), |
| LinkerFlavor::Msvc(Lld::No) |
| if sess.opts.cg.linker.is_none() && sess.target.linker.is_none() => |
| { |
| Command::new(msvc_tool.as_ref().map_or(linker, |t| t.path())) |
| } |
| _ => Command::new(linker), |
| }, |
| }; |
| |
| // UWP apps have API restrictions enforced during Store submissions. |
| // To comply with the Windows App Certification Kit, |
| // MSVC needs to link with the Store versions of the runtime libraries (vcruntime, msvcrt, etc). |
| let t = &sess.target; |
| if matches!(flavor, LinkerFlavor::Msvc(..)) && t.vendor == "uwp" { |
| if let Some(ref tool) = msvc_tool { |
| let original_path = tool.path(); |
| if let Some(root_lib_path) = original_path.ancestors().nth(4) { |
| let arch = match t.arch.as_ref() { |
| "x86_64" => Some("x64"), |
| "x86" => Some("x86"), |
| "aarch64" => Some("arm64"), |
| "arm" => Some("arm"), |
| _ => None, |
| }; |
| if let Some(ref a) = arch { |
| // FIXME: Move this to `fn linker_with_args`. |
| let mut arg = OsString::from("/LIBPATH:"); |
| arg.push(format!("{}\\lib\\{}\\store", root_lib_path.display(), a)); |
| cmd.arg(&arg); |
| } else { |
| warn!("arch is not supported"); |
| } |
| } else { |
| warn!("MSVC root path lib location not found"); |
| } |
| } else { |
| warn!("link.exe not found"); |
| } |
| } |
| |
| // The compiler's sysroot often has some bundled tools, so add it to the |
| // PATH for the child. |
| let mut new_path = sess.get_tools_search_paths(self_contained); |
| let mut msvc_changed_path = false; |
| if sess.target.is_like_msvc { |
| if let Some(ref tool) = msvc_tool { |
| cmd.args(tool.args()); |
| for (k, v) in tool.env() { |
| if k == "PATH" { |
| new_path.extend(env::split_paths(v)); |
| msvc_changed_path = true; |
| } else { |
| cmd.env(k, v); |
| } |
| } |
| } |
| } |
| |
| if !msvc_changed_path { |
| if let Some(path) = env::var_os("PATH") { |
| new_path.extend(env::split_paths(&path)); |
| } |
| } |
| cmd.env("PATH", env::join_paths(new_path).unwrap()); |
| |
| // FIXME: Move `/LIBPATH` addition for uwp targets from the linker construction |
| // to the linker args construction. |
| assert!(cmd.get_args().is_empty() || sess.target.vendor == "uwp"); |
| match flavor { |
| LinkerFlavor::Unix(Cc::No) if sess.target.os == "l4re" => { |
| Box::new(L4Bender::new(cmd, sess)) as Box<dyn Linker> |
| } |
| LinkerFlavor::Unix(Cc::No) if sess.target.os == "aix" => { |
| Box::new(AixLinker::new(cmd, sess)) as Box<dyn Linker> |
| } |
| LinkerFlavor::WasmLld(Cc::No) => Box::new(WasmLd::new(cmd, sess)) as Box<dyn Linker>, |
| LinkerFlavor::Gnu(cc, _) |
| | LinkerFlavor::Darwin(cc, _) |
| | LinkerFlavor::WasmLld(cc) |
| | LinkerFlavor::Unix(cc) => Box::new(GccLinker { |
| cmd, |
| sess, |
| target_cpu, |
| hinted_static: None, |
| is_ld: cc == Cc::No, |
| is_gnu: flavor.is_gnu(), |
| }) as Box<dyn Linker>, |
| LinkerFlavor::Msvc(..) => Box::new(MsvcLinker { cmd, sess }) as Box<dyn Linker>, |
| LinkerFlavor::EmCc => Box::new(EmLinker { cmd, sess }) as Box<dyn Linker>, |
| LinkerFlavor::Bpf => Box::new(BpfLinker { cmd, sess }) as Box<dyn Linker>, |
| LinkerFlavor::Llbc => Box::new(LlbcLinker { cmd, sess }) as Box<dyn Linker>, |
| LinkerFlavor::Ptx => Box::new(PtxLinker { cmd, sess }) as Box<dyn Linker>, |
| } |
| } |
| |
| // Note: Ideally neither these helper function, nor the macro-generated inherent methods below |
| // would exist, and these functions would live in `trait Linker`. |
| // Unfortunately, adding these functions to `trait Linker` make it `dyn`-incompatible. |
| // If the methods are added to the trait with `where Self: Sized` bounds, then even a separate |
| // implementation of them for `dyn Linker {}` wouldn't work due to a conflict with those |
| // uncallable methods in the trait. |
| |
| /// Just pass the arguments to the linker as is. |
| /// It is assumed that they are correctly prepared in advance. |
| fn verbatim_args<L: Linker + ?Sized>( |
| l: &mut L, |
| args: impl IntoIterator<Item: AsRef<OsStr>>, |
| ) -> &mut L { |
| for arg in args { |
| l.cmd().arg(arg); |
| } |
| l |
| } |
| /// Arguments for the underlying linker. |
| /// Add options to pass them through cc wrapper if `Linker` is a cc wrapper. |
| fn link_args<L: Linker + ?Sized>( |
| l: &mut L, |
| args: impl IntoIterator<Item: AsRef<OsStr>, IntoIter: ExactSizeIterator>, |
| ) -> &mut L { |
| let args = args.into_iter(); |
| if !l.is_cc() { |
| verbatim_args(l, args); |
| } else if args.len() != 0 { |
| // FIXME: Support arguments with commas, see `rpaths_to_flags` for the example. |
| let mut combined_arg = OsString::from("-Wl"); |
| for arg in args { |
| combined_arg.push(","); |
| combined_arg.push(arg); |
| } |
| l.cmd().arg(combined_arg); |
| } |
| l |
| } |
| /// Arguments for the cc wrapper specifically. |
| /// Check that it's indeed a cc wrapper and pass verbatim. |
| fn cc_args<L: Linker + ?Sized>(l: &mut L, args: impl IntoIterator<Item: AsRef<OsStr>>) -> &mut L { |
| assert!(l.is_cc()); |
| verbatim_args(l, args) |
| } |
| /// Arguments supported by both underlying linker and cc wrapper, pass verbatim. |
| fn link_or_cc_args<L: Linker + ?Sized>( |
| l: &mut L, |
| args: impl IntoIterator<Item: AsRef<OsStr>>, |
| ) -> &mut L { |
| verbatim_args(l, args) |
| } |
| |
| macro_rules! generate_arg_methods { |
| ($($ty:ty)*) => { $( |
| impl $ty { |
| #[allow(unused)] |
| pub(crate) fn verbatim_args(&mut self, args: impl IntoIterator<Item: AsRef<OsStr>>) -> &mut Self { |
| verbatim_args(self, args) |
| } |
| #[allow(unused)] |
| pub(crate) fn verbatim_arg(&mut self, arg: impl AsRef<OsStr>) -> &mut Self { |
| verbatim_args(self, iter::once(arg)) |
| } |
| #[allow(unused)] |
| pub(crate) fn link_args(&mut self, args: impl IntoIterator<Item: AsRef<OsStr>, IntoIter: ExactSizeIterator>) -> &mut Self { |
| link_args(self, args) |
| } |
| #[allow(unused)] |
| pub(crate) fn link_arg(&mut self, arg: impl AsRef<OsStr>) -> &mut Self { |
| link_args(self, iter::once(arg)) |
| } |
| #[allow(unused)] |
| pub(crate) fn cc_args(&mut self, args: impl IntoIterator<Item: AsRef<OsStr>>) -> &mut Self { |
| cc_args(self, args) |
| } |
| #[allow(unused)] |
| pub(crate) fn cc_arg(&mut self, arg: impl AsRef<OsStr>) -> &mut Self { |
| cc_args(self, iter::once(arg)) |
| } |
| #[allow(unused)] |
| pub(crate) fn link_or_cc_args(&mut self, args: impl IntoIterator<Item: AsRef<OsStr>>) -> &mut Self { |
| link_or_cc_args(self, args) |
| } |
| #[allow(unused)] |
| pub(crate) fn link_or_cc_arg(&mut self, arg: impl AsRef<OsStr>) -> &mut Self { |
| link_or_cc_args(self, iter::once(arg)) |
| } |
| } |
| )* } |
| } |
| |
| generate_arg_methods! { |
| GccLinker<'_> |
| MsvcLinker<'_> |
| EmLinker<'_> |
| WasmLd<'_> |
| L4Bender<'_> |
| AixLinker<'_> |
| LlbcLinker<'_> |
| PtxLinker<'_> |
| BpfLinker<'_> |
| dyn Linker + '_ |
| } |
| |
| /// Linker abstraction used by `back::link` to build up the command to invoke a |
| /// linker. |
| /// |
| /// This trait is the total list of requirements needed by `back::link` and |
| /// represents the meaning of each option being passed down. This trait is then |
| /// used to dispatch on whether a GNU-like linker (generally `ld.exe`) or an |
| /// MSVC linker (e.g., `link.exe`) is being used. |
| pub(crate) trait Linker { |
| fn cmd(&mut self) -> &mut Command; |
| fn is_cc(&self) -> bool { |
| false |
| } |
| fn set_output_kind( |
| &mut self, |
| output_kind: LinkOutputKind, |
| crate_type: CrateType, |
| out_filename: &Path, |
| ); |
| fn link_dylib_by_name(&mut self, _name: &str, _verbatim: bool, _as_needed: bool) { |
| bug!("dylib linked with unsupported linker") |
| } |
| fn link_dylib_by_path(&mut self, _path: &Path, _as_needed: bool) { |
| bug!("dylib linked with unsupported linker") |
| } |
| fn link_framework_by_name(&mut self, _name: &str, _verbatim: bool, _as_needed: bool) { |
| bug!("framework linked with unsupported linker") |
| } |
| fn link_staticlib_by_name(&mut self, name: &str, verbatim: bool, whole_archive: bool); |
| fn link_staticlib_by_path(&mut self, path: &Path, whole_archive: bool); |
| fn include_path(&mut self, path: &Path) { |
| link_or_cc_args(link_or_cc_args(self, &["-L"]), &[path]); |
| } |
| fn framework_path(&mut self, _path: &Path) { |
| bug!("framework path set with unsupported linker") |
| } |
| fn output_filename(&mut self, path: &Path) { |
| link_or_cc_args(link_or_cc_args(self, &["-o"]), &[path]); |
| } |
| fn add_object(&mut self, path: &Path) { |
| link_or_cc_args(self, &[path]); |
| } |
| fn gc_sections(&mut self, keep_metadata: bool); |
| fn no_gc_sections(&mut self); |
| fn full_relro(&mut self); |
| fn partial_relro(&mut self); |
| fn no_relro(&mut self); |
| fn optimize(&mut self); |
| fn pgo_gen(&mut self); |
| fn control_flow_guard(&mut self); |
| fn ehcont_guard(&mut self); |
| fn debuginfo(&mut self, strip: Strip, natvis_debugger_visualizers: &[PathBuf]); |
| fn no_crt_objects(&mut self); |
| fn no_default_libraries(&mut self); |
| fn export_symbols(&mut self, tmpdir: &Path, crate_type: CrateType, symbols: &[String]); |
| fn subsystem(&mut self, subsystem: &str); |
| fn linker_plugin_lto(&mut self); |
| fn add_eh_frame_header(&mut self) {} |
| fn add_no_exec(&mut self) {} |
| fn add_as_needed(&mut self) {} |
| fn reset_per_library_state(&mut self) {} |
| } |
| |
| impl dyn Linker + '_ { |
| pub(crate) fn take_cmd(&mut self) -> Command { |
| mem::replace(self.cmd(), Command::new("")) |
| } |
| } |
| |
| struct GccLinker<'a> { |
| cmd: Command, |
| sess: &'a Session, |
| target_cpu: &'a str, |
| hinted_static: Option<bool>, // Keeps track of the current hinting mode. |
| // Link as ld |
| is_ld: bool, |
| is_gnu: bool, |
| } |
| |
| impl<'a> GccLinker<'a> { |
| fn takes_hints(&self) -> bool { |
| // Really this function only returns true if the underlying linker |
| // configured for a compiler is binutils `ld.bfd` and `ld.gold`. We |
| // don't really have a foolproof way to detect that, so rule out some |
| // platforms where currently this is guaranteed to *not* be the case: |
| // |
| // * On OSX they have their own linker, not binutils' |
| // * For WebAssembly the only functional linker is LLD, which doesn't |
| // support hint flags |
| !self.sess.target.is_like_osx && !self.sess.target.is_like_wasm |
| } |
| |
| // Some platforms take hints about whether a library is static or dynamic. |
| // For those that support this, we ensure we pass the option if the library |
| // was flagged "static" (most defaults are dynamic) to ensure that if |
| // libfoo.a and libfoo.so both exist that the right one is chosen. |
| fn hint_static(&mut self) { |
| if !self.takes_hints() { |
| return; |
| } |
| if self.hinted_static != Some(true) { |
| self.link_arg("-Bstatic"); |
| self.hinted_static = Some(true); |
| } |
| } |
| |
| fn hint_dynamic(&mut self) { |
| if !self.takes_hints() { |
| return; |
| } |
| if self.hinted_static != Some(false) { |
| self.link_arg("-Bdynamic"); |
| self.hinted_static = Some(false); |
| } |
| } |
| |
| fn push_linker_plugin_lto_args(&mut self, plugin_path: Option<&OsStr>) { |
| if let Some(plugin_path) = plugin_path { |
| let mut arg = OsString::from("-plugin="); |
| arg.push(plugin_path); |
| self.link_arg(&arg); |
| } |
| |
| let opt_level = match self.sess.opts.optimize { |
| config::OptLevel::No => "O0", |
| config::OptLevel::Less => "O1", |
| config::OptLevel::Default | config::OptLevel::Size | config::OptLevel::SizeMin => "O2", |
| config::OptLevel::Aggressive => "O3", |
| }; |
| |
| if let Some(path) = &self.sess.opts.unstable_opts.profile_sample_use { |
| self.link_arg(&format!("-plugin-opt=sample-profile={}", path.display())); |
| }; |
| self.link_args(&[ |
| &format!("-plugin-opt={opt_level}"), |
| &format!("-plugin-opt=mcpu={}", self.target_cpu), |
| ]); |
| } |
| |
| fn build_dylib(&mut self, crate_type: CrateType, out_filename: &Path) { |
| // On mac we need to tell the linker to let this library be rpathed |
| if self.sess.target.is_like_osx { |
| if self.is_cc() { |
| // `-dynamiclib` makes `cc` pass `-dylib` to the linker. |
| self.cc_arg("-dynamiclib"); |
| } else { |
| self.link_arg("-dylib"); |
| // Clang also sets `-dynamic`, but that's implied by `-dylib`, so unnecessary. |
| } |
| |
| // Note that the `osx_rpath_install_name` option here is a hack |
| // purely to support bootstrap right now, we should get a more |
| // principled solution at some point to force the compiler to pass |
| // the right `-Wl,-install_name` with an `@rpath` in it. |
| if self.sess.opts.cg.rpath || self.sess.opts.unstable_opts.osx_rpath_install_name { |
| let mut rpath = OsString::from("@rpath/"); |
| rpath.push(out_filename.file_name().unwrap()); |
| self.link_arg("-install_name").link_arg(rpath); |
| } |
| } else { |
| self.link_or_cc_arg("-shared"); |
| if let Some(name) = out_filename.file_name() { |
| if self.sess.target.is_like_windows { |
| // The output filename already contains `dll_suffix` so |
| // the resulting import library will have a name in the |
| // form of libfoo.dll.a |
| let mut implib_name = OsString::from(&*self.sess.target.staticlib_prefix); |
| implib_name.push(name); |
| implib_name.push(&*self.sess.target.staticlib_suffix); |
| let mut out_implib = OsString::from("--out-implib="); |
| out_implib.push(out_filename.with_file_name(implib_name)); |
| self.link_arg(out_implib); |
| } else if crate_type == CrateType::Dylib { |
| // When dylibs are linked by a full path this value will get into `DT_NEEDED` |
| // instead of the full path, so the library can be later found in some other |
| // location than that specific path. |
| let mut soname = OsString::from("-soname="); |
| soname.push(name); |
| self.link_arg(soname); |
| } |
| } |
| } |
| } |
| |
| fn with_as_needed(&mut self, as_needed: bool, f: impl FnOnce(&mut Self)) { |
| if !as_needed { |
| if self.sess.target.is_like_osx { |
| // FIXME(81490): ld64 doesn't support these flags but macOS 11 |
| // has -needed-l{} / -needed_library {} |
| // but we have no way to detect that here. |
| self.sess.dcx().emit_warn(errors::Ld64UnimplementedModifier); |
| } else if self.is_gnu && !self.sess.target.is_like_windows { |
| self.link_arg("--no-as-needed"); |
| } else { |
| self.sess.dcx().emit_warn(errors::LinkerUnsupportedModifier); |
| } |
| } |
| |
| f(self); |
| |
| if !as_needed { |
| if self.sess.target.is_like_osx { |
| // See above FIXME comment |
| } else if self.is_gnu && !self.sess.target.is_like_windows { |
| self.link_arg("--as-needed"); |
| } |
| } |
| } |
| } |
| |
| impl<'a> Linker for GccLinker<'a> { |
| fn cmd(&mut self) -> &mut Command { |
| &mut self.cmd |
| } |
| |
| fn is_cc(&self) -> bool { |
| !self.is_ld |
| } |
| |
| fn set_output_kind( |
| &mut self, |
| output_kind: LinkOutputKind, |
| crate_type: CrateType, |
| out_filename: &Path, |
| ) { |
| match output_kind { |
| LinkOutputKind::DynamicNoPicExe => { |
| if !self.is_ld && self.is_gnu { |
| self.cc_arg("-no-pie"); |
| } |
| } |
| LinkOutputKind::DynamicPicExe => { |
| // noop on windows w/ gcc & ld, error w/ lld |
| if !self.sess.target.is_like_windows { |
| // `-pie` works for both gcc wrapper and ld. |
| self.link_or_cc_arg("-pie"); |
| } |
| } |
| LinkOutputKind::StaticNoPicExe => { |
| // `-static` works for both gcc wrapper and ld. |
| self.link_or_cc_arg("-static"); |
| if !self.is_ld && self.is_gnu { |
| self.cc_arg("-no-pie"); |
| } |
| } |
| LinkOutputKind::StaticPicExe => { |
| if !self.is_ld { |
| // Note that combination `-static -pie` doesn't work as expected |
| // for the gcc wrapper, `-static` in that case suppresses `-pie`. |
| self.cc_arg("-static-pie"); |
| } else { |
| // `--no-dynamic-linker` and `-z text` are not strictly necessary for producing |
| // a static pie, but currently passed because gcc and clang pass them. |
| // The former suppresses the `INTERP` ELF header specifying dynamic linker, |
| // which is otherwise implicitly injected by ld (but not lld). |
| // The latter doesn't change anything, only ensures that everything is pic. |
| self.link_args(&["-static", "-pie", "--no-dynamic-linker", "-z", "text"]); |
| } |
| } |
| LinkOutputKind::DynamicDylib => self.build_dylib(crate_type, out_filename), |
| LinkOutputKind::StaticDylib => { |
| self.link_or_cc_arg("-static"); |
| self.build_dylib(crate_type, out_filename); |
| } |
| LinkOutputKind::WasiReactorExe => { |
| self.link_args(&["--entry", "_initialize"]); |
| } |
| } |
| // VxWorks compiler driver introduced `--static-crt` flag specifically for rustc, |
| // it switches linking for libc and similar system libraries to static without using |
| // any `#[link]` attributes in the `libc` crate, see #72782 for details. |
| // FIXME: Switch to using `#[link]` attributes in the `libc` crate |
| // similarly to other targets. |
| if self.sess.target.os == "vxworks" |
| && matches!( |
| output_kind, |
| LinkOutputKind::StaticNoPicExe |
| | LinkOutputKind::StaticPicExe |
| | LinkOutputKind::StaticDylib |
| ) |
| { |
| self.cc_arg("--static-crt"); |
| } |
| } |
| |
| fn link_dylib_by_name(&mut self, name: &str, verbatim: bool, as_needed: bool) { |
| if self.sess.target.os == "illumos" && name == "c" { |
| // libc will be added via late_link_args on illumos so that it will |
| // appear last in the library search order. |
| // FIXME: This should be replaced by a more complete and generic |
| // mechanism for controlling the order of library arguments passed |
| // to the linker. |
| return; |
| } |
| self.hint_dynamic(); |
| self.with_as_needed(as_needed, |this| { |
| let colon = if verbatim && this.is_gnu { ":" } else { "" }; |
| this.link_or_cc_arg(format!("-l{colon}{name}")); |
| }); |
| } |
| |
| fn link_dylib_by_path(&mut self, path: &Path, as_needed: bool) { |
| self.hint_dynamic(); |
| self.with_as_needed(as_needed, |this| { |
| this.link_or_cc_arg(path); |
| }) |
| } |
| |
| fn link_framework_by_name(&mut self, name: &str, _verbatim: bool, as_needed: bool) { |
| self.hint_dynamic(); |
| if !as_needed { |
| // FIXME(81490): ld64 as of macOS 11 supports the -needed_framework |
| // flag but we have no way to detect that here. |
| // self.link_or_cc_arg("-needed_framework").link_or_cc_arg(name); |
| self.sess.dcx().emit_warn(errors::Ld64UnimplementedModifier); |
| } |
| self.link_or_cc_args(&["-framework", name]); |
| } |
| |
| fn link_staticlib_by_name(&mut self, name: &str, verbatim: bool, whole_archive: bool) { |
| self.hint_static(); |
| let colon = if verbatim && self.is_gnu { ":" } else { "" }; |
| if !whole_archive { |
| self.link_or_cc_arg(format!("-l{colon}{name}")); |
| } else if self.sess.target.is_like_osx { |
| // -force_load is the macOS equivalent of --whole-archive, but it |
| // involves passing the full path to the library to link. |
| self.link_arg("-force_load"); |
| self.link_arg(find_native_static_library(name, verbatim, self.sess)); |
| } else { |
| self.link_arg("--whole-archive") |
| .link_or_cc_arg(format!("-l{colon}{name}")) |
| .link_arg("--no-whole-archive"); |
| } |
| } |
| |
| fn link_staticlib_by_path(&mut self, path: &Path, whole_archive: bool) { |
| self.hint_static(); |
| if !whole_archive { |
| self.link_or_cc_arg(path); |
| } else if self.sess.target.is_like_osx { |
| self.link_arg("-force_load").link_arg(path); |
| } else { |
| self.link_arg("--whole-archive").link_arg(path).link_arg("--no-whole-archive"); |
| } |
| } |
| |
| fn framework_path(&mut self, path: &Path) { |
| self.link_or_cc_arg("-F").link_or_cc_arg(path); |
| } |
| fn full_relro(&mut self) { |
| self.link_args(&["-z", "relro", "-z", "now"]); |
| } |
| fn partial_relro(&mut self) { |
| self.link_args(&["-z", "relro"]); |
| } |
| fn no_relro(&mut self) { |
| self.link_args(&["-z", "norelro"]); |
| } |
| |
| fn gc_sections(&mut self, keep_metadata: bool) { |
| // The dead_strip option to the linker specifies that functions and data |
| // unreachable by the entry point will be removed. This is quite useful |
| // with Rust's compilation model of compiling libraries at a time into |
| // one object file. For example, this brings hello world from 1.7MB to |
| // 458K. |
| // |
| // Note that this is done for both executables and dynamic libraries. We |
| // won't get much benefit from dylibs because LLVM will have already |
| // stripped away as much as it could. This has not been seen to impact |
| // link times negatively. |
| // |
| // -dead_strip can't be part of the pre_link_args because it's also used |
| // for partial linking when using multiple codegen units (-r). So we |
| // insert it here. |
| if self.sess.target.is_like_osx { |
| self.link_arg("-dead_strip"); |
| |
| // If we're building a dylib, we don't use --gc-sections because LLVM |
| // has already done the best it can do, and we also don't want to |
| // eliminate the metadata. If we're building an executable, however, |
| // --gc-sections drops the size of hello world from 1.8MB to 597K, a 67% |
| // reduction. |
| } else if (self.is_gnu || self.sess.target.is_like_wasm) && !keep_metadata { |
| self.link_arg("--gc-sections"); |
| } |
| } |
| |
| fn no_gc_sections(&mut self) { |
| if self.is_gnu || self.sess.target.is_like_wasm { |
| self.link_arg("--no-gc-sections"); |
| } |
| } |
| |
| fn optimize(&mut self) { |
| if !self.is_gnu && !self.sess.target.is_like_wasm { |
| return; |
| } |
| |
| // GNU-style linkers support optimization with -O. GNU ld doesn't |
| // need a numeric argument, but other linkers do. |
| if self.sess.opts.optimize == config::OptLevel::Default |
| || self.sess.opts.optimize == config::OptLevel::Aggressive |
| { |
| self.link_arg("-O1"); |
| } |
| } |
| |
| fn pgo_gen(&mut self) { |
| if !self.is_gnu { |
| return; |
| } |
| |
| // If we're doing PGO generation stuff and on a GNU-like linker, use the |
| // "-u" flag to properly pull in the profiler runtime bits. |
| // |
| // This is because LLVM otherwise won't add the needed initialization |
| // for us on Linux (though the extra flag should be harmless if it |
| // does). |
| // |
| // See https://reviews.llvm.org/D14033 and https://reviews.llvm.org/D14030. |
| // |
| // Though it may be worth to try to revert those changes upstream, since |
| // the overhead of the initialization should be minor. |
| self.link_or_cc_args(&["-u", "__llvm_profile_runtime"]); |
| } |
| |
| fn control_flow_guard(&mut self) {} |
| |
| fn ehcont_guard(&mut self) {} |
| |
| fn debuginfo(&mut self, strip: Strip, _: &[PathBuf]) { |
| // MacOS linker doesn't support stripping symbols directly anymore. |
| if self.sess.target.is_like_osx { |
| return; |
| } |
| |
| match strip { |
| Strip::None => {} |
| Strip::Debuginfo => { |
| // The illumos linker does not support --strip-debug although |
| // it does support --strip-all as a compatibility alias for -s. |
| // The --strip-debug case is handled by running an external |
| // `strip` utility as a separate step after linking. |
| if !self.sess.target.is_like_solaris { |
| self.link_arg("--strip-debug"); |
| } |
| } |
| Strip::Symbols => { |
| self.link_arg("--strip-all"); |
| } |
| } |
| match self.sess.opts.unstable_opts.debuginfo_compression { |
| config::DebugInfoCompression::None => {} |
| config::DebugInfoCompression::Zlib => { |
| self.link_arg("--compress-debug-sections=zlib"); |
| } |
| config::DebugInfoCompression::Zstd => { |
| self.link_arg("--compress-debug-sections=zstd"); |
| } |
| } |
| } |
| |
| fn no_crt_objects(&mut self) { |
| if !self.is_ld { |
| self.cc_arg("-nostartfiles"); |
| } |
| } |
| |
| fn no_default_libraries(&mut self) { |
| if !self.is_ld { |
| self.cc_arg("-nodefaultlibs"); |
| } |
| } |
| |
| fn export_symbols(&mut self, tmpdir: &Path, crate_type: CrateType, symbols: &[String]) { |
| // Symbol visibility in object files typically takes care of this. |
| if crate_type == CrateType::Executable { |
| let should_export_executable_symbols = |
| self.sess.opts.unstable_opts.export_executable_symbols; |
| if self.sess.target.override_export_symbols.is_none() |
| && !should_export_executable_symbols |
| { |
| return; |
| } |
| } |
| |
| // We manually create a list of exported symbols to ensure we don't expose any more. |
| // The object files have far more public symbols than we actually want to export, |
| // so we hide them all here. |
| |
| if !self.sess.target.limit_rdylib_exports { |
| return; |
| } |
| |
| let is_windows = self.sess.target.is_like_windows; |
| let path = tmpdir.join(if is_windows { "list.def" } else { "list" }); |
| |
| debug!("EXPORTED SYMBOLS:"); |
| |
| if self.sess.target.is_like_osx { |
| // Write a plain, newline-separated list of symbols |
| let res: io::Result<()> = try { |
| let mut f = File::create_buffered(&path)?; |
| for sym in symbols { |
| debug!(" _{sym}"); |
| writeln!(f, "_{sym}")?; |
| } |
| }; |
| if let Err(error) = res { |
| self.sess.dcx().emit_fatal(errors::LibDefWriteFailure { error }); |
| } |
| } else if is_windows { |
| let res: io::Result<()> = try { |
| let mut f = File::create_buffered(&path)?; |
| |
| // .def file similar to MSVC one but without LIBRARY section |
| // because LD doesn't like when it's empty |
| writeln!(f, "EXPORTS")?; |
| for symbol in symbols { |
| debug!(" _{symbol}"); |
| writeln!(f, " {symbol}")?; |
| } |
| }; |
| if let Err(error) = res { |
| self.sess.dcx().emit_fatal(errors::LibDefWriteFailure { error }); |
| } |
| } else { |
| // Write an LD version script |
| let res: io::Result<()> = try { |
| let mut f = File::create_buffered(&path)?; |
| writeln!(f, "{{")?; |
| if !symbols.is_empty() { |
| writeln!(f, " global:")?; |
| for sym in symbols { |
| debug!(" {sym};"); |
| writeln!(f, " {sym};")?; |
| } |
| } |
| writeln!(f, "\n local:\n *;\n}};")?; |
| }; |
| if let Err(error) = res { |
| self.sess.dcx().emit_fatal(errors::VersionScriptWriteFailure { error }); |
| } |
| } |
| |
| if self.sess.target.is_like_osx { |
| self.link_arg("-exported_symbols_list").link_arg(path); |
| } else if self.sess.target.is_like_solaris { |
| self.link_arg("-M").link_arg(path); |
| } else if is_windows { |
| self.link_arg(path); |
| } else { |
| let mut arg = OsString::from("--version-script="); |
| arg.push(path); |
| self.link_arg(arg).link_arg("--no-undefined-version"); |
| } |
| } |
| |
| fn subsystem(&mut self, subsystem: &str) { |
| self.link_args(&["--subsystem", subsystem]); |
| } |
| |
| fn reset_per_library_state(&mut self) { |
| self.hint_dynamic(); // Reset to default before returning the composed command line. |
| } |
| |
| fn linker_plugin_lto(&mut self) { |
| match self.sess.opts.cg.linker_plugin_lto { |
| LinkerPluginLto::Disabled => { |
| // Nothing to do |
| } |
| LinkerPluginLto::LinkerPluginAuto => { |
| self.push_linker_plugin_lto_args(None); |
| } |
| LinkerPluginLto::LinkerPlugin(ref path) => { |
| self.push_linker_plugin_lto_args(Some(path.as_os_str())); |
| } |
| } |
| } |
| |
| // Add the `GNU_EH_FRAME` program header which is required to locate unwinding information. |
| // Some versions of `gcc` add it implicitly, some (e.g. `musl-gcc`) don't, |
| // so we just always add it. |
| fn add_eh_frame_header(&mut self) { |
| self.link_arg("--eh-frame-hdr"); |
| } |
| |
| fn add_no_exec(&mut self) { |
| if self.sess.target.is_like_windows { |
| self.link_arg("--nxcompat"); |
| } else if self.is_gnu { |
| self.link_args(&["-z", "noexecstack"]); |
| } |
| } |
| |
| fn add_as_needed(&mut self) { |
| if self.is_gnu && !self.sess.target.is_like_windows { |
| self.link_arg("--as-needed"); |
| } else if self.sess.target.is_like_solaris { |
| // -z ignore is the Solaris equivalent to the GNU ld --as-needed option |
| self.link_args(&["-z", "ignore"]); |
| } |
| } |
| } |
| |
| struct MsvcLinker<'a> { |
| cmd: Command, |
| sess: &'a Session, |
| } |
| |
| impl<'a> Linker for MsvcLinker<'a> { |
| fn cmd(&mut self) -> &mut Command { |
| &mut self.cmd |
| } |
| |
| fn set_output_kind( |
| &mut self, |
| output_kind: LinkOutputKind, |
| _crate_type: CrateType, |
| out_filename: &Path, |
| ) { |
| match output_kind { |
| LinkOutputKind::DynamicNoPicExe |
| | LinkOutputKind::DynamicPicExe |
| | LinkOutputKind::StaticNoPicExe |
| | LinkOutputKind::StaticPicExe => {} |
| LinkOutputKind::DynamicDylib | LinkOutputKind::StaticDylib => { |
| self.link_arg("/DLL"); |
| let mut arg: OsString = "/IMPLIB:".into(); |
| arg.push(out_filename.with_extension("dll.lib")); |
| self.link_arg(arg); |
| } |
| LinkOutputKind::WasiReactorExe => { |
| panic!("can't link as reactor on non-wasi target"); |
| } |
| } |
| } |
| |
| fn link_dylib_by_name(&mut self, name: &str, verbatim: bool, _as_needed: bool) { |
| // On MSVC-like targets rustc supports import libraries using alternative naming |
| // scheme (`libfoo.a`) unsupported by linker, search for such libraries manually. |
| if let Some(path) = try_find_native_dynamic_library(self.sess, name, verbatim) { |
| self.link_arg(path); |
| } else { |
| self.link_arg(format!("{}{}", name, if verbatim { "" } else { ".lib" })); |
| } |
| } |
| |
| fn link_dylib_by_path(&mut self, path: &Path, _as_needed: bool) { |
| // When producing a dll, MSVC linker may not emit an implib file if the dll doesn't export |
| // any symbols, so we skip linking if the implib file is not present. |
| let implib_path = path.with_extension("dll.lib"); |
| if implib_path.exists() { |
| self.link_or_cc_arg(implib_path); |
| } |
| } |
| |
| fn link_staticlib_by_name(&mut self, name: &str, verbatim: bool, whole_archive: bool) { |
| // On MSVC-like targets rustc supports static libraries using alternative naming |
| // scheme (`libfoo.a`) unsupported by linker, search for such libraries manually. |
| if let Some(path) = try_find_native_static_library(self.sess, name, verbatim) { |
| self.link_staticlib_by_path(&path, whole_archive); |
| } else { |
| let prefix = if whole_archive { "/WHOLEARCHIVE:" } else { "" }; |
| let suffix = if verbatim { "" } else { ".lib" }; |
| self.link_arg(format!("{prefix}{name}{suffix}")); |
| } |
| } |
| |
| fn link_staticlib_by_path(&mut self, path: &Path, whole_archive: bool) { |
| if !whole_archive { |
| self.link_arg(path); |
| } else { |
| let mut arg = OsString::from("/WHOLEARCHIVE:"); |
| arg.push(path); |
| self.link_arg(arg); |
| } |
| } |
| |
| fn gc_sections(&mut self, _keep_metadata: bool) { |
| // MSVC's ICF (Identical COMDAT Folding) link optimization is |
| // slow for Rust and thus we disable it by default when not in |
| // optimization build. |
| if self.sess.opts.optimize != config::OptLevel::No { |
| self.link_arg("/OPT:REF,ICF"); |
| } else { |
| // It is necessary to specify NOICF here, because /OPT:REF |
| // implies ICF by default. |
| self.link_arg("/OPT:REF,NOICF"); |
| } |
| } |
| |
| fn no_gc_sections(&mut self) { |
| self.link_arg("/OPT:NOREF,NOICF"); |
| } |
| |
| fn full_relro(&mut self) { |
| // noop |
| } |
| |
| fn partial_relro(&mut self) { |
| // noop |
| } |
| |
| fn no_relro(&mut self) { |
| // noop |
| } |
| |
| fn no_crt_objects(&mut self) { |
| // noop |
| } |
| |
| fn no_default_libraries(&mut self) { |
| self.link_arg("/NODEFAULTLIB"); |
| } |
| |
| fn include_path(&mut self, path: &Path) { |
| let mut arg = OsString::from("/LIBPATH:"); |
| arg.push(path); |
| self.link_arg(&arg); |
| } |
| |
| fn output_filename(&mut self, path: &Path) { |
| let mut arg = OsString::from("/OUT:"); |
| arg.push(path); |
| self.link_arg(&arg); |
| } |
| |
| fn optimize(&mut self) { |
| // Needs more investigation of `/OPT` arguments |
| } |
| |
| fn pgo_gen(&mut self) { |
| // Nothing needed here. |
| } |
| |
| fn control_flow_guard(&mut self) { |
| self.link_arg("/guard:cf"); |
| } |
| |
| fn ehcont_guard(&mut self) { |
| if self.sess.target.pointer_width == 64 { |
| self.link_arg("/guard:ehcont"); |
| } |
| } |
| |
| fn debuginfo(&mut self, _strip: Strip, natvis_debugger_visualizers: &[PathBuf]) { |
| // This will cause the Microsoft linker to generate a PDB file |
| // from the CodeView line tables in the object files. |
| self.link_arg("/DEBUG"); |
| |
| // Default to emitting only the file name of the PDB file into |
| // the binary instead of the full path. Emitting the full path |
| // may leak private information (such as user names). |
| // See https://github.com/rust-lang/rust/issues/87825. |
| // |
| // This default behavior can be overridden by explicitly passing |
| // `-Clink-arg=/PDBALTPATH:...` to rustc. |
| self.link_arg("/PDBALTPATH:%_PDB%"); |
| |
| // This will cause the Microsoft linker to embed .natvis info into the PDB file |
| let natvis_dir_path = self.sess.sysroot.join("lib\\rustlib\\etc"); |
| if let Ok(natvis_dir) = fs::read_dir(&natvis_dir_path) { |
| for entry in natvis_dir { |
| match entry { |
| Ok(entry) => { |
| let path = entry.path(); |
| if path.extension() == Some("natvis".as_ref()) { |
| let mut arg = OsString::from("/NATVIS:"); |
| arg.push(path); |
| self.link_arg(arg); |
| } |
| } |
| Err(error) => { |
| self.sess.dcx().emit_warn(errors::NoNatvisDirectory { error }); |
| } |
| } |
| } |
| } |
| |
| // This will cause the Microsoft linker to embed .natvis info for all crates into the PDB file |
| for path in natvis_debugger_visualizers { |
| let mut arg = OsString::from("/NATVIS:"); |
| arg.push(path); |
| self.link_arg(arg); |
| } |
| } |
| |
| // Currently the compiler doesn't use `dllexport` (an LLVM attribute) to |
| // export symbols from a dynamic library. When building a dynamic library, |
| // however, we're going to want some symbols exported, so this function |
| // generates a DEF file which lists all the symbols. |
| // |
| // The linker will read this `*.def` file and export all the symbols from |
| // the dynamic library. Note that this is not as simple as just exporting |
| // all the symbols in the current crate (as specified by `codegen.reachable`) |
| // but rather we also need to possibly export the symbols of upstream |
| // crates. Upstream rlibs may be linked statically to this dynamic library, |
| // in which case they may continue to transitively be used and hence need |
| // their symbols exported. |
| fn export_symbols(&mut self, tmpdir: &Path, crate_type: CrateType, symbols: &[String]) { |
| // Symbol visibility takes care of this typically |
| if crate_type == CrateType::Executable { |
| let should_export_executable_symbols = |
| self.sess.opts.unstable_opts.export_executable_symbols; |
| if !should_export_executable_symbols { |
| return; |
| } |
| } |
| |
| let path = tmpdir.join("lib.def"); |
| let res: io::Result<()> = try { |
| let mut f = File::create_buffered(&path)?; |
| |
| // Start off with the standard module name header and then go |
| // straight to exports. |
| writeln!(f, "LIBRARY")?; |
| writeln!(f, "EXPORTS")?; |
| for symbol in symbols { |
| debug!(" _{symbol}"); |
| writeln!(f, " {symbol}")?; |
| } |
| }; |
| if let Err(error) = res { |
| self.sess.dcx().emit_fatal(errors::LibDefWriteFailure { error }); |
| } |
| let mut arg = OsString::from("/DEF:"); |
| arg.push(path); |
| self.link_arg(&arg); |
| } |
| |
| fn subsystem(&mut self, subsystem: &str) { |
| // Note that previous passes of the compiler validated this subsystem, |
| // so we just blindly pass it to the linker. |
| self.link_arg(&format!("/SUBSYSTEM:{subsystem}")); |
| |
| // Windows has two subsystems we're interested in right now, the console |
| // and windows subsystems. These both implicitly have different entry |
| // points (starting symbols). The console entry point starts with |
| // `mainCRTStartup` and the windows entry point starts with |
| // `WinMainCRTStartup`. These entry points, defined in system libraries, |
| // will then later probe for either `main` or `WinMain`, respectively to |
| // start the application. |
| // |
| // In Rust we just always generate a `main` function so we want control |
| // to always start there, so we force the entry point on the windows |
| // subsystem to be `mainCRTStartup` to get everything booted up |
| // correctly. |
| // |
| // For more information see RFC #1665 |
| if subsystem == "windows" { |
| self.link_arg("/ENTRY:mainCRTStartup"); |
| } |
| } |
| |
| fn linker_plugin_lto(&mut self) { |
| // Do nothing |
| } |
| |
| fn add_no_exec(&mut self) { |
| self.link_arg("/NXCOMPAT"); |
| } |
| } |
| |
| struct EmLinker<'a> { |
| cmd: Command, |
| sess: &'a Session, |
| } |
| |
| impl<'a> Linker for EmLinker<'a> { |
| fn cmd(&mut self) -> &mut Command { |
| &mut self.cmd |
| } |
| |
| fn is_cc(&self) -> bool { |
| true |
| } |
| |
| fn set_output_kind( |
| &mut self, |
| _output_kind: LinkOutputKind, |
| _crate_type: CrateType, |
| _out_filename: &Path, |
| ) { |
| } |
| |
| fn link_dylib_by_name(&mut self, name: &str, _verbatim: bool, _as_needed: bool) { |
| // Emscripten always links statically |
| self.link_or_cc_args(&["-l", name]); |
| } |
| |
| fn link_dylib_by_path(&mut self, path: &Path, _as_needed: bool) { |
| self.link_or_cc_arg(path); |
| } |
| |
| fn link_staticlib_by_name(&mut self, name: &str, _verbatim: bool, _whole_archive: bool) { |
| self.link_or_cc_args(&["-l", name]); |
| } |
| |
| fn link_staticlib_by_path(&mut self, path: &Path, _whole_archive: bool) { |
| self.link_or_cc_arg(path); |
| } |
| |
| fn full_relro(&mut self) { |
| // noop |
| } |
| |
| fn partial_relro(&mut self) { |
| // noop |
| } |
| |
| fn no_relro(&mut self) { |
| // noop |
| } |
| |
| fn gc_sections(&mut self, _keep_metadata: bool) { |
| // noop |
| } |
| |
| fn no_gc_sections(&mut self) { |
| // noop |
| } |
| |
| fn optimize(&mut self) { |
| // Emscripten performs own optimizations |
| self.cc_arg(match self.sess.opts.optimize { |
| OptLevel::No => "-O0", |
| OptLevel::Less => "-O1", |
| OptLevel::Default => "-O2", |
| OptLevel::Aggressive => "-O3", |
| OptLevel::Size => "-Os", |
| OptLevel::SizeMin => "-Oz", |
| }); |
| } |
| |
| fn pgo_gen(&mut self) { |
| // noop, but maybe we need something like the gnu linker? |
| } |
| |
| fn control_flow_guard(&mut self) {} |
| |
| fn ehcont_guard(&mut self) {} |
| |
| fn debuginfo(&mut self, _strip: Strip, _: &[PathBuf]) { |
| // Preserve names or generate source maps depending on debug info |
| // For more information see https://emscripten.org/docs/tools_reference/emcc.html#emcc-g |
| self.cc_arg(match self.sess.opts.debuginfo { |
| DebugInfo::None => "-g0", |
| DebugInfo::Limited | DebugInfo::LineTablesOnly | DebugInfo::LineDirectivesOnly => { |
| "--profiling-funcs" |
| } |
| DebugInfo::Full => "-g", |
| }); |
| } |
| |
| fn no_crt_objects(&mut self) {} |
| |
| fn no_default_libraries(&mut self) { |
| self.cc_arg("-nodefaultlibs"); |
| } |
| |
| fn export_symbols(&mut self, _tmpdir: &Path, _crate_type: CrateType, symbols: &[String]) { |
| debug!("EXPORTED SYMBOLS:"); |
| |
| self.cc_arg("-s"); |
| |
| let mut arg = OsString::from("EXPORTED_FUNCTIONS="); |
| let encoded = serde_json::to_string( |
| &symbols.iter().map(|sym| "_".to_owned() + sym).collect::<Vec<_>>(), |
| ) |
| .unwrap(); |
| debug!("{encoded}"); |
| |
| arg.push(encoded); |
| |
| self.cc_arg(arg); |
| } |
| |
| fn subsystem(&mut self, _subsystem: &str) { |
| // noop |
| } |
| |
| fn linker_plugin_lto(&mut self) { |
| // Do nothing |
| } |
| } |
| |
| struct WasmLd<'a> { |
| cmd: Command, |
| sess: &'a Session, |
| } |
| |
| impl<'a> WasmLd<'a> { |
| fn new(cmd: Command, sess: &'a Session) -> WasmLd<'a> { |
| // If the atomics feature is enabled for wasm then we need a whole bunch |
| // of flags: |
| // |
| // * `--shared-memory` - the link won't even succeed without this, flags |
| // the one linear memory as `shared` |
| // |
| // * `--max-memory=1G` - when specifying a shared memory this must also |
| // be specified. We conservatively choose 1GB but users should be able |
| // to override this with `-C link-arg`. |
| // |
| // * `--import-memory` - it doesn't make much sense for memory to be |
| // exported in a threaded module because typically you're |
| // sharing memory and instantiating the module multiple times. As a |
| // result if it were exported then we'd just have no sharing. |
| // |
| // On wasm32-unknown-unknown, we also export symbols for glue code to use: |
| // * `--export=*tls*` - when `#[thread_local]` symbols are used these |
| // symbols are how the TLS segments are initialized and configured. |
| let mut wasm_ld = WasmLd { cmd, sess }; |
| if sess.target_features.contains(&sym::atomics) { |
| wasm_ld.link_args(&["--shared-memory", "--max-memory=1073741824", "--import-memory"]); |
| if sess.target.os == "unknown" { |
| wasm_ld.link_args(&[ |
| "--export=__wasm_init_tls", |
| "--export=__tls_size", |
| "--export=__tls_align", |
| "--export=__tls_base", |
| ]); |
| } |
| } |
| wasm_ld |
| } |
| } |
| |
| impl<'a> Linker for WasmLd<'a> { |
| fn cmd(&mut self) -> &mut Command { |
| &mut self.cmd |
| } |
| |
| fn set_output_kind( |
| &mut self, |
| output_kind: LinkOutputKind, |
| _crate_type: CrateType, |
| _out_filename: &Path, |
| ) { |
| match output_kind { |
| LinkOutputKind::DynamicNoPicExe |
| | LinkOutputKind::DynamicPicExe |
| | LinkOutputKind::StaticNoPicExe |
| | LinkOutputKind::StaticPicExe => {} |
| LinkOutputKind::DynamicDylib | LinkOutputKind::StaticDylib => { |
| self.link_arg("--no-entry"); |
| } |
| LinkOutputKind::WasiReactorExe => { |
| self.link_args(&["--entry", "_initialize"]); |
| } |
| } |
| } |
| |
| fn link_dylib_by_name(&mut self, name: &str, _verbatim: bool, _as_needed: bool) { |
| self.link_or_cc_args(&["-l", name]); |
| } |
| |
| fn link_dylib_by_path(&mut self, path: &Path, _as_needed: bool) { |
| self.link_or_cc_arg(path); |
| } |
| |
| fn link_staticlib_by_name(&mut self, name: &str, _verbatim: bool, whole_archive: bool) { |
| if !whole_archive { |
| self.link_or_cc_args(&["-l", name]); |
| } else { |
| self.link_arg("--whole-archive") |
| .link_or_cc_args(&["-l", name]) |
| .link_arg("--no-whole-archive"); |
| } |
| } |
| |
| fn link_staticlib_by_path(&mut self, path: &Path, whole_archive: bool) { |
| if !whole_archive { |
| self.link_or_cc_arg(path); |
| } else { |
| self.link_arg("--whole-archive").link_or_cc_arg(path).link_arg("--no-whole-archive"); |
| } |
| } |
| |
| fn full_relro(&mut self) {} |
| |
| fn partial_relro(&mut self) {} |
| |
| fn no_relro(&mut self) {} |
| |
| fn gc_sections(&mut self, _keep_metadata: bool) { |
| self.link_arg("--gc-sections"); |
| } |
| |
| fn no_gc_sections(&mut self) { |
| self.link_arg("--no-gc-sections"); |
| } |
| |
| fn optimize(&mut self) { |
| // The -O flag is, as of late 2023, only used for merging of strings and debuginfo, and |
| // only differentiates -O0 and -O1. It does not apply to LTO. |
| self.link_arg(match self.sess.opts.optimize { |
| OptLevel::No => "-O0", |
| OptLevel::Less => "-O1", |
| OptLevel::Default => "-O2", |
| OptLevel::Aggressive => "-O3", |
| // Currently LLD doesn't support `Os` and `Oz`, so pass through `O2` |
| // instead. |
| OptLevel::Size => "-O2", |
| OptLevel::SizeMin => "-O2", |
| }); |
| } |
| |
| fn pgo_gen(&mut self) {} |
| |
| fn debuginfo(&mut self, strip: Strip, _: &[PathBuf]) { |
| match strip { |
| Strip::None => {} |
| Strip::Debuginfo => { |
| self.link_arg("--strip-debug"); |
| } |
| Strip::Symbols => { |
| self.link_arg("--strip-all"); |
| } |
| } |
| } |
| |
| fn control_flow_guard(&mut self) {} |
| |
| fn ehcont_guard(&mut self) {} |
| |
| fn no_crt_objects(&mut self) {} |
| |
| fn no_default_libraries(&mut self) {} |
| |
| fn export_symbols(&mut self, _tmpdir: &Path, _crate_type: CrateType, symbols: &[String]) { |
| for sym in symbols { |
| self.link_args(&["--export", sym]); |
| } |
| |
| // LLD will hide these otherwise-internal symbols since it only exports |
| // symbols explicitly passed via the `--export` flags above and hides all |
| // others. Various bits and pieces of wasm32-unknown-unknown tooling use |
| // this, so be sure these symbols make their way out of the linker as well. |
| if self.sess.target.os == "unknown" { |
| self.link_args(&["--export=__heap_base", "--export=__data_end"]); |
| } |
| } |
| |
| fn subsystem(&mut self, _subsystem: &str) {} |
| |
| fn linker_plugin_lto(&mut self) { |
| match self.sess.opts.cg.linker_plugin_lto { |
| LinkerPluginLto::Disabled => { |
| // Nothing to do |
| } |
| LinkerPluginLto::LinkerPluginAuto => { |
| self.push_linker_plugin_lto_args(); |
| } |
| LinkerPluginLto::LinkerPlugin(_) => { |
| self.push_linker_plugin_lto_args(); |
| } |
| } |
| } |
| } |
| |
| impl<'a> WasmLd<'a> { |
| fn push_linker_plugin_lto_args(&mut self) { |
| let opt_level = match self.sess.opts.optimize { |
| config::OptLevel::No => "O0", |
| config::OptLevel::Less => "O1", |
| config::OptLevel::Default => "O2", |
| config::OptLevel::Aggressive => "O3", |
| // wasm-ld only handles integer LTO opt levels. Use O2 |
| config::OptLevel::Size | config::OptLevel::SizeMin => "O2", |
| }; |
| self.link_arg(&format!("--lto-{opt_level}")); |
| } |
| } |
| |
| /// Linker shepherd script for L4Re (Fiasco) |
| struct L4Bender<'a> { |
| cmd: Command, |
| sess: &'a Session, |
| hinted_static: bool, |
| } |
| |
| impl<'a> Linker for L4Bender<'a> { |
| fn cmd(&mut self) -> &mut Command { |
| &mut self.cmd |
| } |
| |
| fn set_output_kind( |
| &mut self, |
| _output_kind: LinkOutputKind, |
| _crate_type: CrateType, |
| _out_filename: &Path, |
| ) { |
| } |
| |
| fn link_staticlib_by_name(&mut self, name: &str, _verbatim: bool, whole_archive: bool) { |
| self.hint_static(); |
| if !whole_archive { |
| self.link_arg(format!("-PC{name}")); |
| } else { |
| self.link_arg("--whole-archive") |
| .link_or_cc_arg(format!("-l{name}")) |
| .link_arg("--no-whole-archive"); |
| } |
| } |
| |
| fn link_staticlib_by_path(&mut self, path: &Path, whole_archive: bool) { |
| self.hint_static(); |
| if !whole_archive { |
| self.link_or_cc_arg(path); |
| } else { |
| self.link_arg("--whole-archive").link_or_cc_arg(path).link_arg("--no-whole-archive"); |
| } |
| } |
| |
| fn full_relro(&mut self) { |
| self.link_args(&["-z", "relro", "-z", "now"]); |
| } |
| |
| fn partial_relro(&mut self) { |
| self.link_args(&["-z", "relro"]); |
| } |
| |
| fn no_relro(&mut self) { |
| self.link_args(&["-z", "norelro"]); |
| } |
| |
| fn gc_sections(&mut self, keep_metadata: bool) { |
| if !keep_metadata { |
| self.link_arg("--gc-sections"); |
| } |
| } |
| |
| fn no_gc_sections(&mut self) { |
| self.link_arg("--no-gc-sections"); |
| } |
| |
| fn optimize(&mut self) { |
| // GNU-style linkers support optimization with -O. GNU ld doesn't |
| // need a numeric argument, but other linkers do. |
| if self.sess.opts.optimize == config::OptLevel::Default |
| || self.sess.opts.optimize == config::OptLevel::Aggressive |
| { |
| self.link_arg("-O1"); |
| } |
| } |
| |
| fn pgo_gen(&mut self) {} |
| |
| fn debuginfo(&mut self, strip: Strip, _: &[PathBuf]) { |
| match strip { |
| Strip::None => {} |
| Strip::Debuginfo => { |
| self.link_arg("--strip-debug"); |
| } |
| Strip::Symbols => { |
| self.link_arg("--strip-all"); |
| } |
| } |
| } |
| |
| fn no_default_libraries(&mut self) { |
| self.cc_arg("-nostdlib"); |
| } |
| |
| fn export_symbols(&mut self, _: &Path, _: CrateType, _: &[String]) { |
| // ToDo, not implemented, copy from GCC |
| self.sess.dcx().emit_warn(errors::L4BenderExportingSymbolsUnimplemented); |
| } |
| |
| fn subsystem(&mut self, subsystem: &str) { |
| self.link_arg(&format!("--subsystem {subsystem}")); |
| } |
| |
| fn reset_per_library_state(&mut self) { |
| self.hint_static(); // Reset to default before returning the composed command line. |
| } |
| |
| fn linker_plugin_lto(&mut self) {} |
| |
| fn control_flow_guard(&mut self) {} |
| |
| fn ehcont_guard(&mut self) {} |
| |
| fn no_crt_objects(&mut self) {} |
| } |
| |
| impl<'a> L4Bender<'a> { |
| fn new(cmd: Command, sess: &'a Session) -> L4Bender<'a> { |
| L4Bender { cmd, sess, hinted_static: false } |
| } |
| |
| fn hint_static(&mut self) { |
| if !self.hinted_static { |
| self.link_or_cc_arg("-static"); |
| self.hinted_static = true; |
| } |
| } |
| } |
| |
| /// Linker for AIX. |
| struct AixLinker<'a> { |
| cmd: Command, |
| sess: &'a Session, |
| hinted_static: Option<bool>, |
| } |
| |
| impl<'a> AixLinker<'a> { |
| fn new(cmd: Command, sess: &'a Session) -> AixLinker<'a> { |
| AixLinker { cmd, sess, hinted_static: None } |
| } |
| |
| fn hint_static(&mut self) { |
| if self.hinted_static != Some(true) { |
| self.link_arg("-bstatic"); |
| self.hinted_static = Some(true); |
| } |
| } |
| |
| fn hint_dynamic(&mut self) { |
| if self.hinted_static != Some(false) { |
| self.link_arg("-bdynamic"); |
| self.hinted_static = Some(false); |
| } |
| } |
| |
| fn build_dylib(&mut self, _out_filename: &Path) { |
| self.link_args(&["-bM:SRE", "-bnoentry"]); |
| // FIXME: Use CreateExportList utility to create export list |
| // and remove -bexpfull. |
| self.link_arg("-bexpfull"); |
| } |
| } |
| |
| impl<'a> Linker for AixLinker<'a> { |
| fn cmd(&mut self) -> &mut Command { |
| &mut self.cmd |
| } |
| |
| fn set_output_kind( |
| &mut self, |
| output_kind: LinkOutputKind, |
| _crate_type: CrateType, |
| out_filename: &Path, |
| ) { |
| match output_kind { |
| LinkOutputKind::DynamicDylib => { |
| self.hint_dynamic(); |
| self.build_dylib(out_filename); |
| } |
| LinkOutputKind::StaticDylib => { |
| self.hint_static(); |
| self.build_dylib(out_filename); |
| } |
| _ => {} |
| } |
| } |
| |
| fn link_dylib_by_name(&mut self, name: &str, _verbatim: bool, _as_needed: bool) { |
| self.hint_dynamic(); |
| self.link_or_cc_arg(format!("-l{name}")); |
| } |
| |
| fn link_dylib_by_path(&mut self, path: &Path, _as_needed: bool) { |
| self.hint_dynamic(); |
| self.link_or_cc_arg(path); |
| } |
| |
| fn link_staticlib_by_name(&mut self, name: &str, verbatim: bool, whole_archive: bool) { |
| self.hint_static(); |
| if !whole_archive { |
| self.link_or_cc_arg(format!("-l{name}")); |
| } else { |
| let mut arg = OsString::from("-bkeepfile:"); |
| arg.push(find_native_static_library(name, verbatim, self.sess)); |
| self.link_or_cc_arg(arg); |
| } |
| } |
| |
| fn link_staticlib_by_path(&mut self, path: &Path, whole_archive: bool) { |
| self.hint_static(); |
| if !whole_archive { |
| self.link_or_cc_arg(path); |
| } else { |
| let mut arg = OsString::from("-bkeepfile:"); |
| arg.push(path); |
| self.link_arg(arg); |
| } |
| } |
| |
| fn full_relro(&mut self) {} |
| |
| fn partial_relro(&mut self) {} |
| |
| fn no_relro(&mut self) {} |
| |
| fn gc_sections(&mut self, _keep_metadata: bool) { |
| self.link_arg("-bgc"); |
| } |
| |
| fn no_gc_sections(&mut self) { |
| self.link_arg("-bnogc"); |
| } |
| |
| fn optimize(&mut self) {} |
| |
| fn pgo_gen(&mut self) { |
| self.link_arg("-bdbg:namedsects:ss"); |
| } |
| |
| fn control_flow_guard(&mut self) {} |
| |
| fn ehcont_guard(&mut self) {} |
| |
| fn debuginfo(&mut self, _: Strip, _: &[PathBuf]) {} |
| |
| fn no_crt_objects(&mut self) {} |
| |
| fn no_default_libraries(&mut self) {} |
| |
| fn export_symbols(&mut self, tmpdir: &Path, _crate_type: CrateType, symbols: &[String]) { |
| let path = tmpdir.join("list.exp"); |
| let res: io::Result<()> = try { |
| let mut f = File::create_buffered(&path)?; |
| // FIXME: use llvm-nm to generate export list. |
| for symbol in symbols { |
| debug!(" _{symbol}"); |
| writeln!(f, " {symbol}")?; |
| } |
| }; |
| if let Err(e) = res { |
| self.sess.dcx().fatal(format!("failed to write export file: {e}")); |
| } |
| self.link_arg(format!("-bE:{}", path.to_str().unwrap())); |
| } |
| |
| fn subsystem(&mut self, _subsystem: &str) {} |
| |
| fn reset_per_library_state(&mut self) { |
| self.hint_dynamic(); |
| } |
| |
| fn linker_plugin_lto(&mut self) {} |
| |
| fn add_eh_frame_header(&mut self) {} |
| |
| fn add_no_exec(&mut self) {} |
| |
| fn add_as_needed(&mut self) {} |
| } |
| |
| fn for_each_exported_symbols_include_dep<'tcx>( |
| tcx: TyCtxt<'tcx>, |
| crate_type: CrateType, |
| mut callback: impl FnMut(ExportedSymbol<'tcx>, SymbolExportInfo, CrateNum), |
| ) { |
| for &(symbol, info) in tcx.exported_symbols(LOCAL_CRATE).iter() { |
| callback(symbol, info, LOCAL_CRATE); |
| } |
| |
| let formats = tcx.dependency_formats(()); |
| let deps = formats.iter().find_map(|(t, list)| (*t == crate_type).then_some(list)).unwrap(); |
| |
| for (index, dep_format) in deps.iter().enumerate() { |
| let cnum = CrateNum::new(index + 1); |
| // For each dependency that we are linking to statically ... |
| if *dep_format == Linkage::Static { |
| for &(symbol, info) in tcx.exported_symbols(cnum).iter() { |
| callback(symbol, info, cnum); |
| } |
| } |
| } |
| } |
| |
| pub(crate) fn exported_symbols(tcx: TyCtxt<'_>, crate_type: CrateType) -> Vec<String> { |
| if let Some(ref exports) = tcx.sess.target.override_export_symbols { |
| return exports.iter().map(ToString::to_string).collect(); |
| } |
| |
| if let CrateType::ProcMacro = crate_type { |
| exported_symbols_for_proc_macro_crate(tcx) |
| } else { |
| exported_symbols_for_non_proc_macro(tcx, crate_type) |
| } |
| } |
| |
| fn exported_symbols_for_non_proc_macro(tcx: TyCtxt<'_>, crate_type: CrateType) -> Vec<String> { |
| let mut symbols = Vec::new(); |
| let export_threshold = symbol_export::crates_export_threshold(&[crate_type]); |
| for_each_exported_symbols_include_dep(tcx, crate_type, |symbol, info, cnum| { |
| if info.level.is_below_threshold(export_threshold) { |
| symbols.push(symbol_export::exporting_symbol_name_for_instance_in_crate( |
| tcx, symbol, cnum, |
| )); |
| } |
| }); |
| |
| symbols |
| } |
| |
| fn exported_symbols_for_proc_macro_crate(tcx: TyCtxt<'_>) -> Vec<String> { |
| // `exported_symbols` will be empty when !should_codegen. |
| if !tcx.sess.opts.output_types.should_codegen() { |
| return Vec::new(); |
| } |
| |
| let stable_crate_id = tcx.stable_crate_id(LOCAL_CRATE); |
| let proc_macro_decls_name = tcx.sess.generate_proc_macro_decls_symbol(stable_crate_id); |
| let metadata_symbol_name = exported_symbols::metadata_symbol_name(tcx); |
| |
| vec![proc_macro_decls_name, metadata_symbol_name] |
| } |
| |
| pub(crate) fn linked_symbols( |
| tcx: TyCtxt<'_>, |
| crate_type: CrateType, |
| ) -> Vec<(String, SymbolExportKind)> { |
| match crate_type { |
| CrateType::Executable | CrateType::Cdylib | CrateType::Dylib => (), |
| CrateType::Staticlib | CrateType::ProcMacro | CrateType::Rlib => { |
| return Vec::new(); |
| } |
| } |
| |
| let mut symbols = Vec::new(); |
| |
| let export_threshold = symbol_export::crates_export_threshold(&[crate_type]); |
| for_each_exported_symbols_include_dep(tcx, crate_type, |symbol, info, cnum| { |
| if info.level.is_below_threshold(export_threshold) || info.used { |
| symbols.push(( |
| symbol_export::linking_symbol_name_for_instance_in_crate(tcx, symbol, cnum), |
| info.kind, |
| )); |
| } |
| }); |
| |
| symbols |
| } |
| |
| /// Much simplified and explicit CLI for the NVPTX linker. The linker operates |
| /// with bitcode and uses LLVM backend to generate a PTX assembly. |
| struct PtxLinker<'a> { |
| cmd: Command, |
| sess: &'a Session, |
| } |
| |
| impl<'a> Linker for PtxLinker<'a> { |
| fn cmd(&mut self) -> &mut Command { |
| &mut self.cmd |
| } |
| |
| fn set_output_kind( |
| &mut self, |
| _output_kind: LinkOutputKind, |
| _crate_type: CrateType, |
| _out_filename: &Path, |
| ) { |
| } |
| |
| fn link_staticlib_by_name(&mut self, _name: &str, _verbatim: bool, _whole_archive: bool) { |
| panic!("staticlibs not supported") |
| } |
| |
| fn link_staticlib_by_path(&mut self, path: &Path, _whole_archive: bool) { |
| self.link_arg("--rlib").link_arg(path); |
| } |
| |
| fn debuginfo(&mut self, _strip: Strip, _: &[PathBuf]) { |
| self.link_arg("--debug"); |
| } |
| |
| fn add_object(&mut self, path: &Path) { |
| self.link_arg("--bitcode").link_arg(path); |
| } |
| |
| fn optimize(&mut self) { |
| match self.sess.lto() { |
| Lto::Thin | Lto::Fat | Lto::ThinLocal => { |
| self.link_arg("-Olto"); |
| } |
| |
| Lto::No => {} |
| } |
| } |
| |
| fn full_relro(&mut self) {} |
| |
| fn partial_relro(&mut self) {} |
| |
| fn no_relro(&mut self) {} |
| |
| fn gc_sections(&mut self, _keep_metadata: bool) {} |
| |
| fn no_gc_sections(&mut self) {} |
| |
| fn pgo_gen(&mut self) {} |
| |
| fn no_crt_objects(&mut self) {} |
| |
| fn no_default_libraries(&mut self) {} |
| |
| fn control_flow_guard(&mut self) {} |
| |
| fn ehcont_guard(&mut self) {} |
| |
| fn export_symbols(&mut self, _tmpdir: &Path, _crate_type: CrateType, _symbols: &[String]) {} |
| |
| fn subsystem(&mut self, _subsystem: &str) {} |
| |
| fn linker_plugin_lto(&mut self) {} |
| } |
| |
| /// The `self-contained` LLVM bitcode linker |
| struct LlbcLinker<'a> { |
| cmd: Command, |
| sess: &'a Session, |
| } |
| |
| impl<'a> Linker for LlbcLinker<'a> { |
| fn cmd(&mut self) -> &mut Command { |
| &mut self.cmd |
| } |
| |
| fn set_output_kind( |
| &mut self, |
| _output_kind: LinkOutputKind, |
| _crate_type: CrateType, |
| _out_filename: &Path, |
| ) { |
| } |
| |
| fn link_staticlib_by_name(&mut self, _name: &str, _verbatim: bool, _whole_archive: bool) { |
| panic!("staticlibs not supported") |
| } |
| |
| fn link_staticlib_by_path(&mut self, path: &Path, _whole_archive: bool) { |
| self.link_or_cc_arg(path); |
| } |
| |
| fn debuginfo(&mut self, _strip: Strip, _: &[PathBuf]) { |
| self.link_arg("--debug"); |
| } |
| |
| fn optimize(&mut self) { |
| match self.sess.opts.optimize { |
| OptLevel::No => "-O0", |
| OptLevel::Less => "-O1", |
| OptLevel::Default => "-O2", |
| OptLevel::Aggressive => "-O3", |
| OptLevel::Size => "-Os", |
| OptLevel::SizeMin => "-Oz", |
| }; |
| } |
| |
| fn full_relro(&mut self) {} |
| |
| fn partial_relro(&mut self) {} |
| |
| fn no_relro(&mut self) {} |
| |
| fn gc_sections(&mut self, _keep_metadata: bool) {} |
| |
| fn no_gc_sections(&mut self) {} |
| |
| fn pgo_gen(&mut self) {} |
| |
| fn no_crt_objects(&mut self) {} |
| |
| fn no_default_libraries(&mut self) {} |
| |
| fn control_flow_guard(&mut self) {} |
| |
| fn ehcont_guard(&mut self) {} |
| |
| fn export_symbols(&mut self, _tmpdir: &Path, _crate_type: CrateType, symbols: &[String]) { |
| match _crate_type { |
| CrateType::Cdylib => { |
| for sym in symbols { |
| self.link_args(&["--export-symbol", sym]); |
| } |
| } |
| _ => (), |
| } |
| } |
| |
| fn subsystem(&mut self, _subsystem: &str) {} |
| |
| fn linker_plugin_lto(&mut self) {} |
| } |
| |
| struct BpfLinker<'a> { |
| cmd: Command, |
| sess: &'a Session, |
| } |
| |
| impl<'a> Linker for BpfLinker<'a> { |
| fn cmd(&mut self) -> &mut Command { |
| &mut self.cmd |
| } |
| |
| fn set_output_kind( |
| &mut self, |
| _output_kind: LinkOutputKind, |
| _crate_type: CrateType, |
| _out_filename: &Path, |
| ) { |
| } |
| |
| fn link_staticlib_by_name(&mut self, _name: &str, _verbatim: bool, _whole_archive: bool) { |
| panic!("staticlibs not supported") |
| } |
| |
| fn link_staticlib_by_path(&mut self, path: &Path, _whole_archive: bool) { |
| self.link_or_cc_arg(path); |
| } |
| |
| fn debuginfo(&mut self, _strip: Strip, _: &[PathBuf]) { |
| self.link_arg("--debug"); |
| } |
| |
| fn optimize(&mut self) { |
| self.link_arg(match self.sess.opts.optimize { |
| OptLevel::No => "-O0", |
| OptLevel::Less => "-O1", |
| OptLevel::Default => "-O2", |
| OptLevel::Aggressive => "-O3", |
| OptLevel::Size => "-Os", |
| OptLevel::SizeMin => "-Oz", |
| }); |
| } |
| |
| fn full_relro(&mut self) {} |
| |
| fn partial_relro(&mut self) {} |
| |
| fn no_relro(&mut self) {} |
| |
| fn gc_sections(&mut self, _keep_metadata: bool) {} |
| |
| fn no_gc_sections(&mut self) {} |
| |
| fn pgo_gen(&mut self) {} |
| |
| fn no_crt_objects(&mut self) {} |
| |
| fn no_default_libraries(&mut self) {} |
| |
| fn control_flow_guard(&mut self) {} |
| |
| fn ehcont_guard(&mut self) {} |
| |
| fn export_symbols(&mut self, tmpdir: &Path, _crate_type: CrateType, symbols: &[String]) { |
| let path = tmpdir.join("symbols"); |
| let res: io::Result<()> = try { |
| let mut f = File::create_buffered(&path)?; |
| for sym in symbols { |
| writeln!(f, "{sym}")?; |
| } |
| }; |
| if let Err(error) = res { |
| self.sess.dcx().emit_fatal(errors::SymbolFileWriteFailure { error }); |
| } else { |
| self.link_arg("--export-symbols").link_arg(&path); |
| } |
| } |
| |
| fn subsystem(&mut self, _subsystem: &str) {} |
| |
| fn linker_plugin_lto(&mut self) {} |
| } |
