The Cargo.toml mentioned in book/getting-started
is missing the section called `[dependencies]`

For normal invocations, print a short error message and exit. When
the verbose option is enabled, also print the backtrace.

Add test to check this resolves rust-lang#24838 and rust-lang#26871.

Fixes rust-lang#32961

In `test/rustdoc/manual_impl.rs` there are now three structs:

* S1 implements and documents required method `a_method`.
* S2 implements and documents `a_method` as well as provided
  method `b_method`.
* S3 implements `a_method` and `b_method`, but only documents
  `b_method`.

For a struct, we want the rendered trait impls to include documentation
if and only if it appears on the trait implementation itself
(since users can just go to the trait definition for anything not
covered in the impl docs). This means we expect:

* S1, S2, and S3 to all include top-level trait impl docs.
* S1, S2, and S3 to exclude all trait definition docs.
* S1 to show impl docs for `a_method`.
* S2 to show impl docs for `a_method` and `b_method`.
* S3 to show impl docs for `b_method`.

These tests cover those cases.

We don't want to render default item docs but previously
`doctraititem` naively delegated to the trait definition in those
cases.

Updated tests to also check that this doesn't strip default item
docs from the trait definition.

The Unix implementation was incorrectly handling failure for reallocation of
over-aligned types by not checking for NULL.

Closes rust-lang#32993

Fix macro hygiene bug

This fixes rust-lang#32922 (EDIT: and fixes rust-lang#31856), macro hygiene bugs.
It is a [breaking-change]. For example, the following would break:
```rust
fn main() {
    let x = true;
    macro_rules! foo { () => {
        let x = 0;
        macro_rules! bar { () => {x} }
        let _: bool = bar!();
        //^ `bar!()` used to resolve the first `x` (a bool),
        //| but will now resolve to the second x (an i32).
    }}
    foo! {};
}
```

r? @nrc

…=alexcrichton

rustbuild: Verify sha256 of downloaded tarballs

Here's a quick first pass at this.

I don't use Python often enough to claim that this is totally Pythonic. I've left off some (almost certainly unnecessary) error handling regarding opening and processing files. The whole tarball is read into memory to calculate the hash, but the file isn't *so* large so that should be fine. I don't care for the output from `raise RuntimeError`, but that's how `run()` does it so I'm following precedent.

Tested by manually changing the value of `expected`, and by modifying the tarball then forcing `rustc_out_of_date()`. Both cases tripped the error.

Closes rust-lang#32902

…llaumeGomez

Update a comment to reflect changes in tidy checks.

…in-getting-started-doc, r=GuillaumeGomez

Doc fix: Update Cargo.toml in book/getting-started

The Cargo.toml mentioned in book/getting-started
is missing the section called `[dependencies]`

fixes rust-lang#32928

…s, r=alexcrichton

Restore trait impl docs

Currently, documentation on methods in trait implementations doesn't get rendered. This changes that;  trait implementations have all documentation associated with impl items displayed (documentation from the trait definition is ignored).

Fixes rust-lang#24838
Fixes rust-lang#26871

implement RFC amendment 1494

Adds `:block` to the follow set for `:ty` and `:path`. See rust-lang/rfcs#1494.

trans: always register an item's symbol, even if duplicated.

Fixes rust-lang#32783 which was introduced by not always registering item symbols in rust-lang#32742.

doc: add missing comma

Accommodate the case where dup lang items are entirely external.

Fixes rust-lang#32961

remove "#" symbols to make the code compile

…id-this-land, r=nagisa

alloc_system: Handle failure properly

The Unix implementation was incorrectly handling failure for reallocation of
over-aligned types by not checking for NULL.

Closes rust-lang#32993