diff options
Diffstat (limited to 'compiler/rustc_codegen_ssa/src/back/link.rs')
| -rw-r--r-- | compiler/rustc_codegen_ssa/src/back/link.rs | 260 |
1 files changed, 127 insertions, 133 deletions
diff --git a/compiler/rustc_codegen_ssa/src/back/link.rs b/compiler/rustc_codegen_ssa/src/back/link.rs index e7a67bc64e3..071c221a188 100644 --- a/compiler/rustc_codegen_ssa/src/back/link.rs +++ b/compiler/rustc_codegen_ssa/src/back/link.rs @@ -24,7 +24,7 @@ use rustc_span::symbol::Symbol; use rustc_span::DebuggerVisualizerFile; use rustc_target::spec::crt_objects::{CrtObjects, LinkSelfContainedDefault}; use rustc_target::spec::{Cc, LinkOutputKind, LinkerFlavor, LinkerFlavorCli, Lld, PanicStrategy}; -use rustc_target::spec::{RelocModel, RelroLevel, SanitizerSet, SplitDebuginfo, Target}; +use rustc_target::spec::{RelocModel, RelroLevel, SanitizerSet, SplitDebuginfo}; use super::archive::{ArchiveBuilder, ArchiveBuilderBuilder}; use super::command::Command; @@ -2512,138 +2512,6 @@ fn add_upstream_rust_crates<'a>( link_dynamic, ); } - - // Converts a library file-stem into a cc -l argument - fn unlib<'a>(target: &Target, stem: &'a str) -> &'a str { - if stem.starts_with("lib") && !target.is_like_windows { &stem[3..] } else { stem } - } - - // Adds the static "rlib" versions of all crates to the command line. - // There's a bit of magic which happens here specifically related to LTO, - // namely that we remove upstream object files. - // - // When performing LTO, almost(*) all of the bytecode from the upstream - // libraries has already been included in our object file output. As a - // result we need to remove the object files in the upstream libraries so - // the linker doesn't try to include them twice (or whine about duplicate - // symbols). We must continue to include the rest of the rlib, however, as - // it may contain static native libraries which must be linked in. - // - // (*) Crates marked with `#![no_builtins]` don't participate in LTO and - // their bytecode wasn't included. The object files in those libraries must - // still be passed to the linker. - // - // Note, however, that if we're not doing LTO we can just pass the rlib - // blindly to the linker (fast) because it's fine if it's not actually - // included as we're at the end of the dependency chain. - fn add_static_crate<'a>( - cmd: &mut dyn Linker, - sess: &'a Session, - archive_builder_builder: &dyn ArchiveBuilderBuilder, - codegen_results: &CodegenResults, - tmpdir: &Path, - cnum: CrateNum, - bundled_lib_file_names: &FxHashSet<Symbol>, - ) { - let src = &codegen_results.crate_info.used_crate_source[&cnum]; - let cratepath = &src.rlib.as_ref().unwrap().0; - - let mut link_upstream = |path: &Path| { - cmd.link_rlib(&fix_windows_verbatim_for_gcc(path)); - }; - - // See the comment above in `link_staticlib` and `link_rlib` for why if - // there's a static library that's not relevant we skip all object - // files. - let native_libs = &codegen_results.crate_info.native_libraries[&cnum]; - let skip_native = native_libs.iter().any(|lib| { - matches!(lib.kind, NativeLibKind::Static { bundle: None | Some(true), .. }) - && !relevant_lib(sess, lib) - }); - - if (!are_upstream_rust_objects_already_included(sess) - || ignored_for_lto(sess, &codegen_results.crate_info, cnum)) - && !skip_native - { - link_upstream(cratepath); - return; - } - - let dst = tmpdir.join(cratepath.file_name().unwrap()); - let name = cratepath.file_name().unwrap().to_str().unwrap(); - let name = &name[3..name.len() - 5]; // chop off lib/.rlib - let bundled_lib_file_names = bundled_lib_file_names.clone(); - - sess.prof.generic_activity_with_arg("link_altering_rlib", name).run(|| { - let canonical_name = name.replace('-', "_"); - let upstream_rust_objects_already_included = - are_upstream_rust_objects_already_included(sess); - let is_builtins = sess.target.no_builtins - || !codegen_results.crate_info.is_no_builtins.contains(&cnum); - - let mut archive = archive_builder_builder.new_archive_builder(sess); - if let Err(error) = archive.add_archive( - cratepath, - Box::new(move |f| { - if f == METADATA_FILENAME { - return true; - } - - let canonical = f.replace('-', "_"); - - let is_rust_object = - canonical.starts_with(&canonical_name) && looks_like_rust_object_file(&f); - - // If we've been requested to skip all native object files - // (those not generated by the rust compiler) then we can skip - // this file. See above for why we may want to do this. - let skip_because_cfg_say_so = skip_native && !is_rust_object; - - // If we're performing LTO and this is a rust-generated object - // file, then we don't need the object file as it's part of the - // LTO module. Note that `#![no_builtins]` is excluded from LTO, - // though, so we let that object file slide. - let skip_because_lto = - upstream_rust_objects_already_included && is_rust_object && is_builtins; - - // We skip native libraries because: - // 1. This native libraries won't be used from the generated rlib, - // so we can throw them away to avoid the copying work. - // 2. We can't allow it to be a single remaining entry in archive - // as some linkers may complain on that. - if bundled_lib_file_names.contains(&Symbol::intern(f)) { - return true; - } - - if skip_because_cfg_say_so || skip_because_lto { - return true; - } - - false - }), - ) { - sess.emit_fatal(errors::RlibArchiveBuildFailure { error }); - } - if archive.build(&dst) { - link_upstream(&dst); - } - }); - } - - // Same thing as above, but for dynamic crates instead of static crates. - fn add_dynamic_crate(cmd: &mut dyn Linker, sess: &Session, cratepath: &Path) { - // Just need to tell the linker about where the library lives and - // what its name is - let parent = cratepath.parent(); - if let Some(dir) = parent { - cmd.include_path(&fix_windows_verbatim_for_gcc(dir)); - } - let filestem = cratepath.file_stem().unwrap().to_str().unwrap(); - cmd.link_rust_dylib( - &unlib(&sess.target, filestem), - parent.unwrap_or_else(|| Path::new("")), - ); - } } fn add_upstream_native_libraries( @@ -2684,6 +2552,132 @@ fn add_upstream_native_libraries( } } +// Adds the static "rlib" versions of all crates to the command line. +// There's a bit of magic which happens here specifically related to LTO, +// namely that we remove upstream object files. +// +// When performing LTO, almost(*) all of the bytecode from the upstream +// libraries has already been included in our object file output. As a +// result we need to remove the object files in the upstream libraries so +// the linker doesn't try to include them twice (or whine about duplicate +// symbols). We must continue to include the rest of the rlib, however, as +// it may contain static native libraries which must be linked in. +// +// (*) Crates marked with `#![no_builtins]` don't participate in LTO and +// their bytecode wasn't included. The object files in those libraries must +// still be passed to the linker. +// +// Note, however, that if we're not doing LTO we can just pass the rlib +// blindly to the linker (fast) because it's fine if it's not actually +// included as we're at the end of the dependency chain. +fn add_static_crate<'a>( + cmd: &mut dyn Linker, + sess: &'a Session, + archive_builder_builder: &dyn ArchiveBuilderBuilder, + codegen_results: &CodegenResults, + tmpdir: &Path, + cnum: CrateNum, + bundled_lib_file_names: &FxHashSet<Symbol>, +) { + let src = &codegen_results.crate_info.used_crate_source[&cnum]; + let cratepath = &src.rlib.as_ref().unwrap().0; + + let mut link_upstream = |path: &Path| { + cmd.link_rlib(&fix_windows_verbatim_for_gcc(path)); + }; + + // See the comment above in `link_staticlib` and `link_rlib` for why if + // there's a static library that's not relevant we skip all object + // files. + let native_libs = &codegen_results.crate_info.native_libraries[&cnum]; + let skip_native = native_libs.iter().any(|lib| { + matches!(lib.kind, NativeLibKind::Static { bundle: None | Some(true), .. }) + && !relevant_lib(sess, lib) + }); + + if (!are_upstream_rust_objects_already_included(sess) + || ignored_for_lto(sess, &codegen_results.crate_info, cnum)) + && !skip_native + { + link_upstream(cratepath); + return; + } + + let dst = tmpdir.join(cratepath.file_name().unwrap()); + let name = cratepath.file_name().unwrap().to_str().unwrap(); + let name = &name[3..name.len() - 5]; // chop off lib/.rlib + let bundled_lib_file_names = bundled_lib_file_names.clone(); + + sess.prof.generic_activity_with_arg("link_altering_rlib", name).run(|| { + let canonical_name = name.replace('-', "_"); + let upstream_rust_objects_already_included = + are_upstream_rust_objects_already_included(sess); + let is_builtins = + sess.target.no_builtins || !codegen_results.crate_info.is_no_builtins.contains(&cnum); + + let mut archive = archive_builder_builder.new_archive_builder(sess); + if let Err(e) = archive.add_archive( + cratepath, + Box::new(move |f| { + if f == METADATA_FILENAME { + return true; + } + + let canonical = f.replace('-', "_"); + + let is_rust_object = + canonical.starts_with(&canonical_name) && looks_like_rust_object_file(&f); + + // If we've been requested to skip all native object files + // (those not generated by the rust compiler) then we can skip + // this file. See above for why we may want to do this. + let skip_because_cfg_say_so = skip_native && !is_rust_object; + + // If we're performing LTO and this is a rust-generated object + // file, then we don't need the object file as it's part of the + // LTO module. Note that `#![no_builtins]` is excluded from LTO, + // though, so we let that object file slide. + let skip_because_lto = + upstream_rust_objects_already_included && is_rust_object && is_builtins; + + // We skip native libraries because: + // 1. This native libraries won't be used from the generated rlib, + // so we can throw them away to avoid the copying work. + // 2. We can't allow it to be a single remaining entry in archive + // as some linkers may complain on that. + if bundled_lib_file_names.contains(&Symbol::intern(f)) { + return true; + } + + if skip_because_cfg_say_so || skip_because_lto { + return true; + } + + false + }), + ) { + sess.fatal(&format!("failed to build archive from rlib: {}", e)); + } + if archive.build(&dst) { + link_upstream(&dst); + } + }); +} + +// Same thing as above, but for dynamic crates instead of static crates. +fn add_dynamic_crate(cmd: &mut dyn Linker, sess: &Session, cratepath: &Path) { + // Just need to tell the linker about where the library lives and + // what its name is + let parent = cratepath.parent(); + if let Some(dir) = parent { + cmd.include_path(&fix_windows_verbatim_for_gcc(dir)); + } + let stem = cratepath.file_stem().unwrap().to_str().unwrap(); + // Convert library file-stem into a cc -l argument. + let prefix = if stem.starts_with("lib") && !sess.target.is_like_windows { 3 } else { 0 }; + cmd.link_rust_dylib(&stem[prefix..], parent.unwrap_or_else(|| Path::new(""))); +} + fn relevant_lib(sess: &Session, lib: &NativeLib) -> bool { match lib.cfg { Some(ref cfg) => rustc_attr::cfg_matches(cfg, &sess.parse_sess, CRATE_NODE_ID, None), |