Merge remote-tracking branch 'origin/master' into gen

Author: alexcrichton

README.md

@@ -135,7 +135,7 @@ Windows build triples are:
     - `i686-pc-windows-msvc`
     - `x86_64-pc-windows-msvc`
 
-The build triple can be specified by either specifying `--build=ABI` when
+The build triple can be specified by either specifying `--build=<triple>` when
 invoking `x.py` commands, or by copying the `config.toml` file (as described
 in Building From Source), and modifying the `build` option under the `[build]`
 section.

RELEASES.md

@@ -92,7 +92,7 @@ Stabilized APIs
 Cargo
 -----
 - [Cargo API token location moved from `~/.cargo/config` to
-  `~/cargo/credentials`.][cargo/3978]
+  `~/.cargo/credentials`.][cargo/3978]
 - [Cargo will now build `main.rs` binaries that are in sub-directories of
   `src/bin`.][cargo/4214] ie. Having `src/bin/server/main.rs` and
   `src/bin/client/main.rs` generates `target/debug/server` and `target/debug/client`
@@ -172,7 +172,6 @@ Compatibility Notes
 [`slice::sort_unstable`]: https://doc.rust-lang.org/std/primitive.slice.html#method.sort_unstable
 [`ste::from_boxed_utf8_unchecked`]: https://doc.rust-lang.org/std/str/fn.from_boxed_utf8_unchecked.html
 [`str::as_bytes_mut`]: https://doc.rust-lang.org/std/primitive.str.html#method.as_bytes_mut
-[`str::as_bytes_mut`]: https://doc.rust-lang.org/std/primitive.str.html#method.as_bytes_mut
 [`str::from_utf8_mut`]: https://doc.rust-lang.org/std/str/fn.from_utf8_mut.html
 [`str::from_utf8_unchecked_mut`]: https://doc.rust-lang.org/std/str/fn.from_utf8_unchecked_mut.html
 [`str::get_mut`]: https://doc.rust-lang.org/std/primitive.str.html#method.get_mut
@@ -898,6 +897,9 @@ Compatibility Notes
 * [Ctrl-Z returns from `Stdin.read()` when reading from the console on
   Windows][38274]
 * [Clean up semantics of `self` in an import list][38313]
+* Reimplemented lifetime elision. This change was almost entirely compatible
+  with existing code, but it did close a number of small bugs and loopholes,
+  as well as being more accepting in some other [cases][41105].
 
 [37057]: https://github.com/rust-lang/rust/pull/37057
 [37761]: https://github.com/rust-lang/rust/pull/37761
@@ -932,6 +934,7 @@ Compatibility Notes
 [39048]: https://github.com/rust-lang/rust/pull/39048
 [39282]: https://github.com/rust-lang/rust/pull/39282
 [39379]: https://github.com/rust-lang/rust/pull/39379
+[41105]: https://github.com/rust-lang/rust/issues/41105
 [`<*const T>::wrapping_offset`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.wrapping_offset
 [`<*mut T>::wrapping_offset`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.wrapping_offset
 [`Duration::checked_add`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.checked_add

config.toml.example

@@ -292,6 +292,12 @@
 # build native code.
 #android-ndk = "/path/to/ndk"
 
+# Force static or dynamic linkage of the standard library for this target. If
+# this target is a host for rustc, this will also affect the linkage of the
+# compiler itself. This is useful for building rustc on targets that normally
+# only use static libraries. If unset, the target's default linkage is used.
+#crt-static = false
+
 # The root location of the MUSL installation directory. The library directory
 # will also need to contain libunwind.a for an unwinding implementation. Note
 # that this option only makes sense for MUSL targets that produce statically

src/bootstrap/README.md

@@ -73,16 +73,19 @@ The script accepts commands, flags, and arguments to determine what to do:
 
 ## Configuring rustbuild
 
-There are currently two primary methods for configuring the rustbuild build
-system. First, the `./configure` options serialized in `config.mk` will be
-parsed and read. That is, if any `./configure` options are passed, they'll be
-handled naturally.
+There are currently two methods for configuring the rustbuild build system.
 
-Next, rustbuild offers a TOML-based configuration system with a `config.toml`
+First, rustbuild offers a TOML-based configuration system with a `config.toml`
 file in the same location as `config.mk`. An example of this configuration can
-be found at `config.toml.example`, and the configuration file
-can also be passed as `--config path/to/config.toml` if the build system is
-being invoked manually (via the python script).
+be found at `config.toml.example`, and the configuration file can also be passed
+as `--config path/to/config.toml` if the build system is being invoked manually
+(via the python script).
+
+Next, the `./configure` options serialized in `config.mk` will be
+parsed and read. That is, if any `./configure` options are passed, they'll be
+handled naturally. `./configure` should almost never be used for local
+installations, and is primarily useful for CI. Prefer to customize behavior
+using `config.toml`.
 
 Finally, rustbuild makes use of the [gcc-rs crate] which has [its own
 method][env-vars] of configuring C compilers and C flags via environment
@@ -310,17 +313,18 @@ After that, each module in rustbuild should have enough documentation to keep
 you up and running. Some general areas that you may be interested in modifying
 are:
 
-* Adding a new build tool? Take a look at `bootstrap/step.rs` for examples of
+* Adding a new build tool? Take a look at `bootstrap/tool.rs` for examples of
   other tools.
 * Adding a new compiler crate? Look no further! Adding crates can be done by
   adding a new directory with `Cargo.toml` followed by configuring all
   `Cargo.toml` files accordingly.
-* Adding a new dependency from crates.io? We're still working on that, so hold
-  off on that for now.
-* Adding a new configuration option? Take a look at `bootstrap/config.rs` or
-  perhaps `bootstrap/flags.rs` and then modify the build elsewhere to read that
-  option.
+* Adding a new dependency from crates.io? This should just work inside the
+  compiler artifacts stage (everything other than libtest and libstd).
+* Adding a new configuration option? You'll want to modify `bootstrap/flags.rs`
+  for command line flags and then `bootstrap/config.rs` to copy the flags to the
+  `Config` struct.
 * Adding a sanity check? Take a look at `bootstrap/sanity.rs`.
 
-If you have any questions feel free to reach out on `#rust-internals` on IRC or
-open an issue in the bug tracker!
+If you have any questions feel free to reach out on `#rust-infra` on IRC or ask on
+internals.rust-lang.org. When you encounter bugs, please file issues on the
+rust-lang/rust issue tracker.

src/bootstrap/bin/rustc.rs

@@ -237,9 +237,13 @@ 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("RUSTC_CRT_STATIC") {
+            if s == "true" {
+                cmd.arg("-C").arg("target-feature=+crt-static");
+            }
+            if s == "false" {
+                cmd.arg("-C").arg("target-feature=-crt-static");
+            }
         }
 
         // Force all crates compiled by this compiler to (a) be unstable and (b)

src/bootstrap/builder.rs

@@ -503,6 +503,10 @@ impl<'a> Builder<'a> {
             cargo.env("RUSTC_METADATA_SUFFIX", "rustc");
         }
 
+        if let Some(x) = self.crt_static(target) {
+            cargo.env("RUSTC_CRT_STATIC", x.to_string());
+        }
+
         // Enable usage of unstable features
         cargo.env("RUSTC_BOOTSTRAP", "1");
         self.add_rust_test_threads(&mut cargo);

src/bootstrap/compile.rs

@@ -77,6 +77,14 @@ impl Step for Std {
                 target,
             });
             println!("Uplifting stage1 std ({} -> {})", from.host, target);
+
+            // Even if we're not building std this stage, the new sysroot must
+            // still contain the musl startup objects.
+            if target.contains("musl") && !target.contains("mips") {
+                let libdir = builder.sysroot_libdir(compiler, target);
+                copy_musl_third_party_objects(build, target, &libdir);
+            }
+
             builder.ensure(StdLink {
                 compiler: from,
                 target_compiler: compiler,
@@ -89,6 +97,11 @@ impl Step for Std {
         println!("Building stage{} std artifacts ({} -> {})", compiler.stage,
                 &compiler.host, target);
 
+        if target.contains("musl") && !target.contains("mips") {
+            let libdir = builder.sysroot_libdir(compiler, target);
+            copy_musl_third_party_objects(build, target, &libdir);
+        }
+
         let out_dir = build.cargo_out(compiler, Mode::Libstd, target);
         build.clear_if_dirty(&out_dir, &builder.rustc(compiler));
         let mut cargo = builder.cargo(compiler, Mode::Libstd, target, "build");
@@ -105,6 +118,20 @@ impl Step for Std {
     }
 }
 
+/// Copies the crt(1,i,n).o startup objects
+///
+/// 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: Interned<String>,
+                                 into: &Path) {
+    for &obj in &["crt1.o", "crti.o", "crtn.o"] {
+        copy(&build.musl_root(target).unwrap().join("lib").join(obj), &into.join(obj));
+    }
+}
+
 /// Configure cargo to compile the standard library, adding appropriate env vars
 /// and such.
 pub fn std_cargo(build: &Build,
@@ -189,10 +216,6 @@ impl Step for StdLink {
         let libdir = builder.sysroot_libdir(target_compiler, target);
         add_to_sysroot(&libdir, &libstd_stamp(build, compiler, target));
 
-        if target.contains("musl") && !target.contains("mips") {
-            copy_musl_third_party_objects(build, target, &libdir);
-        }
-
         if build.config.sanitizers && compiler.stage != 0 && target == "x86_64-apple-darwin" {
             // The sanitizers are only built in stage1 or above, so the dylibs will
             // be missing in stage0 and causes panic. See the `std()` function above
@@ -208,15 +231,6 @@ impl Step for StdLink {
     }
 }
 
-/// Copies the crt(1,i,n).o startup objects
-///
-/// Only required for musl targets that statically link to libc
-fn copy_musl_third_party_objects(build: &Build, target: Interned<String>, into: &Path) {
-    for &obj in &["crt1.o", "crti.o", "crtn.o"] {
-        copy(&build.musl_root(target).unwrap().join("lib").join(obj), &into.join(obj));
-    }
-}
-
 fn copy_apple_sanitizer_dylibs(native_dir: &Path, platform: &str, into: &Path) {
     for &sanitizer in &["asan", "tsan"] {
         let filename = format!("libclang_rt.{}_{}_dynamic.dylib", sanitizer, platform);

src/bootstrap/config.rs

@@ -143,6 +143,7 @@ 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>,
 }
@@ -275,6 +276,7 @@ struct TomlTarget {
     cc: Option<String>,
     cxx: Option<String>,
     android_ndk: Option<String>,
+    crt_static: Option<bool>,
     musl_root: Option<String>,
     qemu_rootfs: Option<String>,
 }
@@ -446,6 +448,7 @@ 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/lib.rs

@@ -656,6 +656,16 @@ impl Build {
         base
     }
 
+    /// Returns if this target should statically link the C runtime, if specified
+    fn crt_static(&self, target: Interned<String>) -> 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: Interned<String>) -> Option<&Path> {
         self.config.target_config.get(&target)

src/bootstrap/sanity.rs

@@ -151,8 +151,15 @@ pub fn check(build: &mut Build) {
             panic!("the iOS target is only supported on macOS");
         }
 
-        // Make sure musl-root is valid if specified
+        // Make sure musl-root is valid
         if target.contains("musl") && !target.contains("mips") {
+            // 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() {