1 //! Some stuff used by rustc that doesn't have many dependencies
3 //! Originally extracted from rustc::back, which was nominally the
4 //! compiler 'backend', though LLVM is rustc's backend, so rustc_target
5 //! is really just odds-and-ends relating to code gen and linking.
6 //! This crate mostly exists to make rustc smaller, so we might put
7 //! more 'stuff' here in the future. It does not have a dependency on
10 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
11 #![feature(assert_matches)]
12 #![feature(associated_type_bounds)]
13 #![feature(exhaustive_patterns)]
15 #![feature(min_specialization)]
16 #![feature(never_type)]
17 #![feature(rustc_attrs)]
18 #![feature(step_trait)]
20 use std::iter::FromIterator;
21 use std::path::{Path, PathBuf};
24 extern crate rustc_macros;
37 /// Requirements for a `StableHashingContext` to be used in this crate.
38 /// This is a hack to allow using the `HashStable_Generic` derive macro
39 /// instead of implementing everything in `rustc_middle`.
40 pub trait HashStableContext {}
42 /// The name of rustc's own place to organize libraries.
44 /// Used to be `rustc`, now the default is `rustlib`.
45 const RUST_LIB_DIR: &str = "rustlib";
47 /// Returns a `rustlib` path for this particular target, relative to the provided sysroot.
49 /// For example: `target_sysroot_path("/usr", "x86_64-unknown-linux-gnu")` =>
50 /// `"lib*/rustlib/x86_64-unknown-linux-gnu"`.
51 pub fn target_rustlib_path(sysroot: &Path, target_triple: &str) -> PathBuf {
52 let libdir = find_libdir(sysroot);
54 Path::new(libdir.as_ref()),
55 Path::new(RUST_LIB_DIR),
56 Path::new(target_triple),
60 /// The name of the directory rustc expects libraries to be located.
61 fn find_libdir(sysroot: &Path) -> std::borrow::Cow<'static, str> {
62 // FIXME: This is a quick hack to make the rustc binary able to locate
63 // Rust libraries in Linux environments where libraries might be installed
64 // to lib64/lib32. This would be more foolproof by basing the sysroot off
65 // of the directory where `librustc_driver` is located, rather than
66 // where the rustc binary is.
67 // If --libdir is set during configuration to the value other than
68 // "lib" (i.e., non-default), this value is used (see issue #16552).
70 #[cfg(target_pointer_width = "64")]
71 const PRIMARY_LIB_DIR: &str = "lib64";
73 #[cfg(target_pointer_width = "32")]
74 const PRIMARY_LIB_DIR: &str = "lib32";
76 const SECONDARY_LIB_DIR: &str = "lib";
78 match option_env!("CFG_LIBDIR_RELATIVE") {
79 None | Some("lib") => {
80 if sysroot.join(PRIMARY_LIB_DIR).join(RUST_LIB_DIR).exists() {
81 PRIMARY_LIB_DIR.into()
83 SECONDARY_LIB_DIR.into()
86 Some(libdir) => libdir.into(),