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 #![cfg_attr(feature = "nightly", feature(assert_matches))]
12 #![cfg_attr(feature = "nightly", feature(associated_type_bounds))]
13 #![cfg_attr(feature = "nightly", feature(exhaustive_patterns))]
14 #![cfg_attr(feature = "nightly", feature(min_specialization))]
15 #![cfg_attr(feature = "nightly", feature(never_type))]
16 #![cfg_attr(feature = "nightly", feature(rustc_attrs))]
17 #![cfg_attr(feature = "nightly", feature(step_trait))]
18 #![deny(rustc::untranslatable_diagnostic)]
19 #![deny(rustc::diagnostic_outside_of_impl)]
21 use std::iter::FromIterator;
22 use std::path::{Path, PathBuf};
25 #[cfg(feature = "nightly")]
26 extern crate rustc_macros;
29 #[cfg(feature = "nightly")]
33 #[cfg(feature = "nightly")]
36 #[cfg(feature = "nightly")]
42 /// Requirements for a `StableHashingContext` to be used in this crate.
43 /// This is a hack to allow using the `HashStable_Generic` derive macro
44 /// instead of implementing everything in `rustc_middle`.
45 pub trait HashStableContext {}
47 /// The name of rustc's own place to organize libraries.
49 /// Used to be `rustc`, now the default is `rustlib`.
50 const RUST_LIB_DIR: &str = "rustlib";
52 /// Returns a `rustlib` path for this particular target, relative to the provided sysroot.
54 /// For example: `target_sysroot_path("/usr", "x86_64-unknown-linux-gnu")` =>
55 /// `"lib*/rustlib/x86_64-unknown-linux-gnu"`.
56 pub fn target_rustlib_path(sysroot: &Path, target_triple: &str) -> PathBuf {
57 let libdir = find_libdir(sysroot);
59 Path::new(libdir.as_ref()),
60 Path::new(RUST_LIB_DIR),
61 Path::new(target_triple),
65 /// The name of the directory rustc expects libraries to be located.
66 fn find_libdir(sysroot: &Path) -> std::borrow::Cow<'static, str> {
67 // FIXME: This is a quick hack to make the rustc binary able to locate
68 // Rust libraries in Linux environments where libraries might be installed
69 // to lib64/lib32. This would be more foolproof by basing the sysroot off
70 // of the directory where `librustc_driver` is located, rather than
71 // where the rustc binary is.
72 // If --libdir is set during configuration to the value other than
73 // "lib" (i.e., non-default), this value is used (see issue #16552).
75 #[cfg(target_pointer_width = "64")]
76 const PRIMARY_LIB_DIR: &str = "lib64";
78 #[cfg(target_pointer_width = "32")]
79 const PRIMARY_LIB_DIR: &str = "lib32";
81 const SECONDARY_LIB_DIR: &str = "lib";
83 match option_env!("CFG_LIBDIR_RELATIVE") {
84 None | Some("lib") => {
85 if sysroot.join(PRIMARY_LIB_DIR).join(RUST_LIB_DIR).exists() {
86 PRIMARY_LIB_DIR.into()
88 SECONDARY_LIB_DIR.into()
91 Some(libdir) => libdir.into(),