Auto merge of #31243 - Manishearth:rollup, r=Manishearth

- Successful merges: #30689, #31186, #31219, #31222, #31226
- Failed merges:

CONTRIBUTING.md

@@ -6,6 +6,7 @@ links to the major sections:
 
 * [Feature Requests](#feature-requests)
 * [Bug Reports](#bug-reports)
+* [The Build System](#the-build-system)
 * [Pull Requests](#pull-requests)
 * [Writing Documentation](#writing-documentation)
 * [Issue Triage](#issue-triage)
@@ -77,6 +78,66 @@ to do this is to invoke `rustc` like this:
 $ RUST_BACKTRACE=1 rustc ...
 ```
 
+## The Build System
+
+Rust's build system allows you to bootstrap the compiler, run tests &
+benchmarks, generate documentation, install a fresh build of Rust, and more.
+It's your best friend when working on Rust, allowing you to compile & test
+your contributions before submission.
+
+All the configuration for the build system lives in [the `mk` directory][mkdir]
+in the project root. It can be hard to follow in places, as it uses some
+advanced Make features which make for some challenging reading. If you have
+questions on the build system internals, try asking in
+[`#rust-internals`][pound-rust-internals].
+
+[mkdir]: https://github.com/rust-lang/rust/tree/master/mk/
+
+### Configuration
+
+Before you can start building the compiler you need to configure the build for
+your system. In most cases, that will just mean using the defaults provided
+for Rust. Configuring involves invoking the `configure` script in the project
+root.
+
+```
+./configure
+```
+
+There are large number of options accepted by this script to alter the
+configuration used later in the build process. Some options to note:
+
+- `--enable-debug` - Build a debug version of the compiler (disables optimizations)
+- `--enable-optimize` - Enable optimizations (can be used with `--enable-debug`
+    to make a debug build with optimizations)
+- `--disable-valgrind-rpass` - Don't run tests with valgrind
+- `--enable-clang` - Prefer clang to gcc for building dependencies (e.g., LLVM)
+- `--enable-ccache` - Invoke clang/gcc with ccache to re-use object files between builds
+- `--enable-compiler-docs` - Build compiler documentation
+
+To see a full list of options, run `./configure --help`.
+
+### Useful Targets
+
+Some common make targets are:
+
+- `make rustc-stage1` - build up to (and including) the first stage. For most
+  cases we don't need to build the stage2 compiler, so we can save time by not
+  building it. The stage1 compiler is a fully functioning compiler and
+  (probably) will be enough to determine if your change works as expected.
+- `make check` - build the full compiler & run all tests (takes a while). This
+  is what gets run by the continuous integration system against your pull
+  request. You should run this before submitting to make sure your tests pass
+  & everything builds in the correct manner.
+- `make check-stage1-std NO_REBUILD=1` - test the standard library without
+  rebuilding the entire compiler
+- `make check TESTNAME=<path-to-test-file>.rs` - Run a single test file
+- `make check-stage1-rpass TESTNAME=<path-to-test-file>.rs` - Run a single
+  rpass test with the stage1 compiler (this will be quicker than running the
+  command above as we only build the stage1 compiler, not the entire thing).
+  You can also leave off the `-rpass` to run all stage1 test types.
+- `make check-stage1-coretest` - Run stage1 tests in `libcore`.
+
 ## Pull Requests
 
 Pull requests are the primary mechanism we use to change Rust. GitHub itself

src/doc/book/crates-and-modules.md

@@ -567,10 +567,11 @@ to it as "sayings". Similarly, the first `use` statement pulls in the
 `ja_greetings` as opposed to simply `greetings`. This can help to avoid
 ambiguity when importing similarly-named items from different places.
 
-The second `use` statement uses a star glob to bring in _all_ symbols from the
-`sayings::japanese::farewells` module. As you can see we can later refer to
+The second `use` statement uses a star glob to bring in all public symbols from
+the `sayings::japanese::farewells` module. As you can see we can later refer to
 the Japanese `goodbye` function with no module qualifiers. This kind of glob
-should be used sparingly.
+should be used sparingly. It’s worth noting that it only imports the public
+symbols, even if the code doing the globbing is in the same module.
 
 The third `use` statement bears more explanation. It's using "brace expansion"
 globbing to compress three `use` statements into one (this sort of syntax

src/doc/book/syntax-index.md

@@ -2,7 +2,7 @@
 
 ## Keywords
 
-* `as`: primitive casting.  See [Casting Between Types (`as`)].
+* `as`: primitive casting, or disambiguating the specific trait containing an item.  See [Casting Between Types (`as`)], [Universal Function Call Syntax (Angle-bracket Form)], [Associated Types].
 * `break`: break out of loop.  See [Loops (Ending Iteration Early)].
 * `const`: constant items and constant raw pointers.  See [`const` and `static`], [Raw Pointers].
 * `continue`: continue to next loop iteration.  See [Loops (Ending Iteration Early)].
@@ -115,8 +115,11 @@
 * `::path`: path relative to the crate root (*i.e.* an explicitly absolute path).  See [Crates and Modules (Re-exporting with `pub use`)].
 * `self::path`: path relative to the current module (*i.e.* an explicitly relative path).  See [Crates and Modules (Re-exporting with `pub use`)].
 * `super::path`: path relative to the parent of the current module.  See [Crates and Modules (Re-exporting with `pub use`)].
-* `type::ident`: associated constants, functions, and types.  See [Associated Types].
+* `type::ident`, `<type as trait>::ident`: associated constants, functions, and types.  See [Associated Types].
 * `<type>::…`: associated item for a type which cannot be directly named (*e.g.* `<&T>::…`, `<[T]>::…`, *etc.*).  See [Associated Types].
+* `trait::method(…)`: disambiguating a method call by naming the trait which defines it. See [Universal Function Call Syntax].
+* `type::method(…)`: disambiguating a method call by naming the type for which it's defined. See [Universal Function Call Syntax].
+* `<type as trait>::method(…)`: disambiguating a method call by naming the trait _and_ type. See [Universal Function Call Syntax (Angle-bracket Form)].
 
 <!-- Generics -->
 
@@ -132,7 +135,8 @@
 <!-- Constraints -->
 
 * `T: U`: generic parameter `T` constrained to types that implement `U`.  See [Traits].
-* `T: 'a`: generic type `T` must outlive lifetime `'a`.
+* `T: 'a`: generic type `T` must outlive lifetime `'a`. When we say that a type 'outlives' the lifetime, we mean that it cannot transitively contain any references with lifetimes shorter than `'a`.
+* `T : 'static`: The generic type `T` contains no borrowed references other than `'static` ones.
 * `'b: 'a`: generic lifetime `'b` must outlive lifetime `'a`.
 * `T: ?Sized`: allow generic type parameter to be a dynamically-sized type.  See [Unsized Types (`?Sized`)].
 * `'a + trait`, `trait + trait`: compound type constraint.  See [Traits (Multiple Trait Bounds)].
@@ -234,6 +238,8 @@
 [Traits (`where` clause)]: traits.html#where-clause
 [Traits (Multiple Trait Bounds)]: traits.html#multiple-trait-bounds
 [Traits]: traits.html
+[Universal Function Call Syntax]: ufcs.html
+[Universal Function Call Syntax (Angle-bracket Form)]: ufcs.html#angle-bracket-form
 [Unsafe]: unsafe.html
 [Unsized Types (`?Sized`)]: unsized-types.html#sized
 [Variable Bindings]: variable-bindings.html

src/doc/reference.md

@@ -2095,7 +2095,7 @@ along with their default settings.  [Compiler
 plugins](book/compiler-plugins.html#lint-plugins) can provide additional lint checks.
 
 ```{.ignore}
-mod m1 {
+pub mod m1 {
     // Missing documentation is ignored here
     #[allow(missing_docs)]
     pub fn undocumented_one() -> i32 { 1 }
@@ -2115,9 +2115,9 @@ check on and off:
 
 ```{.ignore}
 #[warn(missing_docs)]
-mod m2{
+pub mod m2{
     #[allow(missing_docs)]
-    mod nested {
+    pub mod nested {
         // Missing documentation is ignored here
         pub fn undocumented_one() -> i32 { 1 }
 
@@ -2137,7 +2137,7 @@ that lint check:
 
 ```{.ignore}
 #[forbid(missing_docs)]
-mod m3 {
+pub mod m3 {
     // Attempting to toggle warning signals an error here
     #[allow(missing_docs)]
     /// Returns 2.