Rollup of 18 pull requests

.gitmodules

@@ -18,6 +18,9 @@
 [submodule "src/liblibc"]
 	path = src/liblibc
 	url = https://github.com/rust-lang/libc.git
+[submodule "src/doc/nomicon"]
+	path = src/doc/nomicon
+	url = https://github.com/rust-lang-nursery/nomicon
 [submodule "src/tools/cargo"]
 	path = src/tools/cargo
 	url = https://github.com/rust-lang/cargo

CONTRIBUTING.md

@@ -406,5 +406,5 @@ are:
 [rr]: https://doc.rust-lang.org/book/README.html
 [tlgba]: http://tomlee.co/2014/04/a-more-detailed-tour-of-the-rust-compiler/
 [ro]: http://www.rustaceans.org/
-[rctd]: ./COMPILER_TESTS.md
+[rctd]: ./src/test/COMPILER_TESTS.md
 [cheatsheet]: https://buildbot.rust-lang.org/homu/

README.md

@@ -149,7 +149,7 @@ $ ./configure
 $ make && sudo make install
 ```
 
-When using the configure script, the generated config.mk` file may override the
+When using the configure script, the generated `config.mk` file may override the
 `config.toml` file. To go back to the `config.toml` file, delete the generated
 `config.mk` file.
 

src/bootstrap/bin/rustc.rs

@@ -207,9 +207,15 @@ fn main() {
             }
         }
 
-        if target.contains("pc-windows-msvc") {
-            cmd.arg("-Z").arg("unstable-options");
-            cmd.arg("-C").arg("target-feature=+crt-static");
+        if let Ok(s) = env::var("RUST_CRT_STATIC") {
+            if s == "true" {
+                cmd.arg("-Z").arg("unstable-options");
+                cmd.arg("-C").arg("target-feature=+crt-static");
+            }
+            if s == "false" {
+                cmd.arg("-Z").arg("unstable-options");
+                cmd.arg("-C").arg("target-feature=-crt-static");
+            }
         }
     }
 

src/bootstrap/compile.rs

@@ -106,14 +106,17 @@ pub fn std_link(build: &Build,
     t!(fs::create_dir_all(&libdir));
     add_to_sysroot(&out_dir, &libdir);
 
-    if target.contains("musl") && !target.contains("mips") {
+    if target.contains("musl") {
         copy_musl_third_party_objects(build, target, &libdir);
     }
 }
 
 /// Copies the crt(1,i,n).o startup objects
 ///
-/// Only required for musl targets that statically link to libc
+/// Since musl supports fully static linking, we can cross link for it even
+/// with a glibc-targeting toolchain, given we have the appropriate startup
+/// files. As those shipped with glibc won't work, copy the ones provided by
+/// musl so we have them on linux-gnu hosts.
 fn copy_musl_third_party_objects(build: &Build, target: &str, into: &Path) {
     for &obj in &["crt1.o", "crti.o", "crtn.o"] {
         copy(&build.musl_root(target).unwrap().join("lib").join(obj), &into.join(obj));

src/bootstrap/config.rs

@@ -59,6 +59,7 @@ pub struct Config {
     pub llvm_static_stdcpp: bool,
     pub llvm_link_shared: bool,
     pub llvm_targets: Option<String>,
+    pub llvm_link_jobs: Option<u32>,
 
     // rust codegen options
     pub rust_optimize: bool,
@@ -117,6 +118,7 @@ pub struct Target {
     pub cc: Option<PathBuf>,
     pub cxx: Option<PathBuf>,
     pub ndk: Option<PathBuf>,
+    pub crt_static: Option<bool>,
     pub musl_root: Option<PathBuf>,
     pub qemu_rootfs: Option<PathBuf>,
 }
@@ -179,6 +181,7 @@ struct Llvm {
     version_check: Option<bool>,
     static_libstdcpp: Option<bool>,
     targets: Option<String>,
+    link_jobs: Option<u32>,
 }
 
 #[derive(RustcDecodable, Default, Clone)]
@@ -231,6 +234,7 @@ struct TomlTarget {
     cc: Option<String>,
     cxx: Option<String>,
     android_ndk: Option<String>,
+    crt_static: Option<bool>,
     musl_root: Option<String>,
     qemu_rootfs: Option<String>,
 }
@@ -333,6 +337,7 @@ impl Config {
             set(&mut config.llvm_version_check, llvm.version_check);
             set(&mut config.llvm_static_stdcpp, llvm.static_libstdcpp);
             config.llvm_targets = llvm.targets.clone();
+            config.llvm_link_jobs = llvm.link_jobs;
         }
 
         if let Some(ref rust) = toml.rust {
@@ -375,6 +380,7 @@ impl Config {
                 }
                 target.cxx = cfg.cxx.clone().map(PathBuf::from);
                 target.cc = cfg.cc.clone().map(PathBuf::from);
+                target.crt_static = cfg.crt_static.clone();
                 target.musl_root = cfg.musl_root.clone().map(PathBuf::from);
                 target.qemu_rootfs = cfg.qemu_rootfs.clone().map(PathBuf::from);
 

src/bootstrap/config.toml.example

@@ -53,6 +53,14 @@
 # Rust team and file an issue if you need assistance in porting!
 #targets = "X86;ARM;AArch64;Mips;PowerPC;SystemZ;JSBackend;MSP430;Sparc;NVPTX"
 
+# Cap the number of parallel linker invocations when compiling LLVM.
+# This can be useful when building LLVM with debug info, which significantly
+# increases the size of binaries and consequently the memory required by
+# each linker process.
+# If absent or 0, linker invocations are treated like any other job and
+# controlled by rustbuild's -j parameter.
+#link-jobs = 0
+
 # =============================================================================
 # General build configuration options
 # =============================================================================

src/bootstrap/lib.rs

@@ -473,6 +473,10 @@ impl Build {
              .env("RUSTDOC_REAL", self.rustdoc(compiler))
              .env("RUSTC_FLAGS", self.rustc_flags(target).join(" "));
 
+        if let Some(x) = self.crt_static(target) {
+             cargo.env("RUST_CRT_STATIC", x.to_string());
+        }
+
         // Enable usage of unstable features
         cargo.env("RUSTC_BOOTSTRAP", "1");
         self.add_rust_test_threads(&mut cargo);
@@ -880,6 +884,16 @@ impl Build {
         return base
     }
 
+    /// Returns if this target should statically link the C runtime, if specified
+    fn crt_static(&self, target: &str) -> Option<bool> {
+        if target.contains("pc-windows-msvc") {
+            Some(true)
+        } else {
+            self.config.target_config.get(target)
+                .and_then(|t| t.crt_static)
+        }
+    }
+
     /// Returns the "musl root" for this `target`, if defined
     fn musl_root(&self, target: &str) -> Option<&Path> {
         self.config.target_config.get(target)

src/bootstrap/native.rs

@@ -115,6 +115,12 @@ pub fn llvm(build: &Build, target: &str) {
         cfg.define("LLVM_BUILD_32_BITS", "ON");
     }
 
+    if let Some(num_linkers) = build.config.llvm_link_jobs {
+        if num_linkers > 0 {
+            cfg.define("LLVM_PARALLEL_LINK_JOBS", num_linkers.to_string());
+        }
+    }
+
     // http://llvm.org/docs/HowToCrossCompileLLVM.html
     if target != build.config.build {
         // FIXME: if the llvm root for the build triple is overridden then we

src/bootstrap/sanity.rs

@@ -157,8 +157,15 @@ pub fn check(build: &mut Build) {
             panic!("the iOS target is only supported on OSX");
         }
 
-        // Make sure musl-root is valid if specified
-        if target.contains("musl") && !target.contains("mips") {
+        // Make sure musl-root is valid
+        if target.contains("musl") {
+            // If this is a native target (host is also musl) and no musl-root is given,
+            // fall back to the system toolchain in /usr before giving up
+            if build.musl_root(target).is_none() && build.config.build == *target {
+                let target = build.config.target_config.entry(target.clone())
+                                 .or_insert(Default::default());
+                target.musl_root = Some("/usr".into());
+            }
             match build.musl_root(target) {
                 Some(root) => {
                     if fs::metadata(root.join("lib/libc.a")).is_err() {

src/build_helper/lib.rs

@@ -12,10 +12,11 @@
 
 extern crate filetime;
 
-use std::{fs, env};
 use std::fs::File;
-use std::process::{Command, Stdio};
+use std::io;
 use std::path::{Path, PathBuf};
+use std::process::{Command, Stdio};
+use std::{fs, env};
 
 use filetime::FileTime;
 
@@ -196,7 +197,7 @@ pub fn native_lib_boilerplate(src_name: &str,
 
     let out_dir = env::var_os("RUSTBUILD_NATIVE_DIR").unwrap_or(env::var_os("OUT_DIR").unwrap());
     let out_dir = PathBuf::from(out_dir).join(out_name);
-    let _ = fs::create_dir_all(&out_dir);
+    t!(create_dir_racy(&out_dir));
     println!("cargo:rustc-link-lib=static={}", link_name);
     println!("cargo:rustc-link-search=native={}", out_dir.join(search_subdir).display());
 
@@ -223,3 +224,21 @@ fn fail(s: &str) -> ! {
     println!("\n\n{}\n\n", s);
     std::process::exit(1);
 }
+
+fn create_dir_racy(path: &Path) -> io::Result<()> {
+    match fs::create_dir(path) {
+        Ok(()) => return Ok(()),
+        Err(ref e) if e.kind() == io::ErrorKind::AlreadyExists => return Ok(()),
+        Err(ref e) if e.kind() == io::ErrorKind::NotFound => {}
+        Err(e) => return Err(e),
+    }
+    match path.parent() {
+        Some(p) => try!(create_dir_racy(p)),
+        None => return Err(io::Error::new(io::ErrorKind::Other, "failed to create whole tree")),
+    }
+    match fs::create_dir(path) {
+        Ok(()) => Ok(()),
+        Err(ref e) if e.kind() == io::ErrorKind::AlreadyExists => Ok(()),
+        Err(e) => Err(e),
+    }
+}

src/doc/index.md

@@ -28,6 +28,7 @@ Rust provides a number of book-length sets of documentation, collectively
 nicknamed 'The Rust Bookshelf.'
 
 * [The Rust Programming Language][book] teaches you how to program in Rust.
+* [The Unstable Book][unstable-book] has documentation for unstable features.
 * [The Rustonomicon][nomicon] is your guidebook to the dark arts of unsafe Rust.
 * [The Reference][ref] is not a formal spec, but is more detailed and comprehensive than the book.
 
@@ -44,4 +45,5 @@ landed before then. That work is being tracked [here][38643].
 [err]: error-index.html
 [book]: book/index.html
 [nomicon]: nomicon/index.html
+[unstable-book]: unstable-book/index.html