From 6b68921ca0d25690e9d7d3b5d6f442fb1bda1fcc Mon Sep 17 00:00:00 2001 From: Vadim Petrochenkov Date: Sat, 6 Aug 2022 18:04:52 +0300 Subject: [PATCH] Change implementation of `-Z gcc-ld` and `lld-wrapper` again --- compiler/rustc_codegen_ssa/src/back/link.rs | 32 ++++++++++--------- src/bootstrap/compile.rs | 4 ++- src/bootstrap/dist.rs | 7 +++-- src/bootstrap/lib.rs | 3 ++ src/tools/lld-wrapper/src/main.rs | 35 +++++++++++---------- 5 files changed, 48 insertions(+), 33 deletions(-) diff --git a/compiler/rustc_codegen_ssa/src/back/link.rs b/compiler/rustc_codegen_ssa/src/back/link.rs index 63207803e327f..085057c3bf3fa 100644 --- a/compiler/rustc_codegen_ssa/src/back/link.rs +++ b/compiler/rustc_codegen_ssa/src/back/link.rs @@ -2777,20 +2777,24 @@ fn add_gcc_ld_path(cmd: &mut dyn Linker, sess: &Session, flavor: LinkerFlavor) { if let LinkerFlavor::Gcc = flavor { match ld_impl { LdImpl::Lld => { - let tools_path = sess.get_tools_search_paths(false); - let gcc_ld_dir = tools_path - .into_iter() - .map(|p| p.join("gcc-ld")) - .find(|p| { - p.join(if sess.host.is_like_windows { "ld.exe" } else { "ld" }).exists() - }) - .unwrap_or_else(|| sess.fatal("rust-lld (as ld) not found")); - cmd.arg({ - let mut arg = OsString::from("-B"); - arg.push(gcc_ld_dir); - arg - }); - cmd.arg(format!("-Wl,-rustc-lld-flavor={}", sess.target.lld_flavor.as_str())); + // Implement the "self-contained" part of -Zgcc-ld + // by adding rustc distribution directories to the tool search path. + for path in sess.get_tools_search_paths(false) { + cmd.arg({ + let mut arg = OsString::from("-B"); + arg.push(path.join("gcc-ld")); + arg + }); + } + // Implement the "linker flavor" part of -Zgcc-ld + // by asking cc to use some kind of lld. + cmd.arg("-fuse-ld=lld"); + if sess.target.lld_flavor != LldFlavor::Ld { + // Tell clang to use a non-default LLD flavor. + // Gcc doesn't understand the target option, but we currently assume + // that gcc is not used for Apple and Wasm targets (#97402). + cmd.arg(format!("--target={}", sess.target.llvm_target)); + } } } } else { diff --git a/src/bootstrap/compile.rs b/src/bootstrap/compile.rs index dd2b9d59366ea..0d89e0a4f25c9 100644 --- a/src/bootstrap/compile.rs +++ b/src/bootstrap/compile.rs @@ -1276,7 +1276,9 @@ impl Step for Assemble { compiler: build_compiler, target: target_compiler.host, }); - builder.copy(&lld_wrapper_exe, &gcc_ld_dir.join(exe("ld", target_compiler.host))); + for name in crate::LLD_FILE_NAMES { + builder.copy(&lld_wrapper_exe, &gcc_ld_dir.join(exe(name, target_compiler.host))); + } } if builder.config.rust_codegen_backends.contains(&INTERNER.intern_str("llvm")) { diff --git a/src/bootstrap/dist.rs b/src/bootstrap/dist.rs index 6291b204e485f..31f71759e249e 100644 --- a/src/bootstrap/dist.rs +++ b/src/bootstrap/dist.rs @@ -423,8 +423,11 @@ impl Step for Rustc { let gcc_lld_src_dir = src_dir.join("gcc-ld"); let gcc_lld_dst_dir = dst_dir.join("gcc-ld"); t!(fs::create_dir(&gcc_lld_dst_dir)); - let exe_name = exe("ld", compiler.host); - builder.copy(&gcc_lld_src_dir.join(&exe_name), &gcc_lld_dst_dir.join(&exe_name)); + for name in crate::LLD_FILE_NAMES { + let exe_name = exe(name, compiler.host); + builder + .copy(&gcc_lld_src_dir.join(&exe_name), &gcc_lld_dst_dir.join(&exe_name)); + } } // Man pages diff --git a/src/bootstrap/lib.rs b/src/bootstrap/lib.rs index f84de73297acb..797e846733176 100644 --- a/src/bootstrap/lib.rs +++ b/src/bootstrap/lib.rs @@ -186,6 +186,9 @@ const LLVM_TOOLS: &[&str] = &[ "opt", // used to optimize LLVM bytecode ]; +/// LLD file names for all flavors. +const LLD_FILE_NAMES: &[&str] = &["ld.lld", "ld64.lld", "lld-link", "wasm-ld"]; + pub const VERSION: usize = 2; /// Extra --check-cfg to add when building diff --git a/src/tools/lld-wrapper/src/main.rs b/src/tools/lld-wrapper/src/main.rs index 90bd24a75e064..1795f3d7fe5bc 100644 --- a/src/tools/lld-wrapper/src/main.rs +++ b/src/tools/lld-wrapper/src/main.rs @@ -8,8 +8,8 @@ //! make gcc/clang pass `-flavor ` as the first two arguments in the linker invocation //! and since Windows does not support symbolic links for files this wrapper is used in place of a //! symbolic link. It execs `../rust-lld -flavor ` by propagating the flavor argument -//! passed to the wrapper as the first two arguments. On Windows it spawns a `..\rust-lld.exe` -//! child process. +//! obtained from the wrapper's name as the first two arguments. +//! On Windows it spawns a `..\rust-lld.exe` child process. use std::fmt::Display; use std::path::{Path, PathBuf}; @@ -53,29 +53,32 @@ fn get_rust_lld_path(current_exe_path: &Path) -> PathBuf { rust_lld_path } +/// Extract LLD flavor name from the lld-wrapper executable name. +fn get_lld_flavor(current_exe_path: &Path) -> Result<&'static str, String> { + let stem = current_exe_path.file_stem(); + Ok(match stem.and_then(|s| s.to_str()) { + Some("ld.lld") => "gnu", + Some("ld64.lld") => "darwin", + Some("lld-link") => "link", + Some("wasm-ld") => "wasm", + _ => return Err(format!("{:?}", stem)), + }) +} + /// Returns the command for invoking rust-lld with the correct flavor. -/// LLD only accepts the flavor argument at the first two arguments, so move it there. +/// LLD only accepts the flavor argument at the first two arguments, so pass it there. /// /// Exits on error. fn get_rust_lld_command(current_exe_path: &Path) -> process::Command { let rust_lld_path = get_rust_lld_path(current_exe_path); let mut command = process::Command::new(rust_lld_path); - let mut flavor = None; - let args = env::args_os() - .skip(1) - .filter(|arg| match arg.to_str().and_then(|s| s.strip_prefix("-rustc-lld-flavor=")) { - Some(suffix) => { - flavor = Some(suffix.to_string()); - false - } - None => true, - }) - .collect::>(); + let flavor = + get_lld_flavor(current_exe_path).unwrap_or_exit_with("executable has unexpected name"); command.arg("-flavor"); - command.arg(flavor.unwrap_or_exit_with("-rustc-lld-flavor= is not passed")); - command.args(args); + command.arg(flavor); + command.args(env::args_os().skip(1)); command }