For the following code:

```rustc
struct Bar;
struct Bar;

fn main () {
}
```

show

```nocode
error[E0428]: a type named `Bar` has already been defined in this module
  --> src/test/compile-fail/E0428.rs:12:1
   |
11 | struct Bar;
   | ----------- previous definition of `Bar` here
12 | struct Bar;
   | ^^^^^^^^^^^

error: aborting due to previous error
```

instead of

```nocode
error[E0428]: a type named `Bar` has already been defined in this module
  --> src/test/compile-fail/E0428.rs:12:1
   |
11 | struct Bar;
   | ----------- previous definition of `Bar` here
12 | struct Bar;
   | ^^^^^^^^^^^

error[E0428]: a value named `Bar` has already been defined in this module
  --> src/test/compile-fail/E0428.rs:12:1
   |
11 | struct Bar;
   | ----------- previous definition of `Bar` here
12 | struct Bar;
   | ^^^^^^^^^^^

error: aborting due to 2 previous errors
```

Rollup of 15 pull requests

- Successful merges: #36868, #37134, #37229, #37250, #37370, #37428, #37432, #37472, #37524, #37614, #37622, #37627, #37636, #37644, #37654
- Failed merges: #37463, #37542, #37645

ICH: Add tests for let- and match-expressions.

r? @nikomatsakis

save-analysis: don't choke on stripped doc attributes

Marking the 'no-stack-check' codegen option as deprecated (Issue #34915)

Attempts to finish resolving issue #34915. Based on pull request #35156, which was closed due to inactivity.

Add missing urls and few local rewrites

r? @steveklabnik

Slightly optimise CString

Avoid a reallocation in CString::from and CStr::to_owned.

macros 1.1: Allow proc_macro functions to declare attributes to be mark as used

This PR allows proc macro functions to declare attribute names that should be marked as used when attached to the deriving item. There are a few questions for this PR.

- Currently this uses a separate attribute named `#[proc_macro_attributes(..)]`, is this the best choice?
- In order to make this work, the `check_attribute` function had to be modified to not error on attributes marked as used. This is a pretty large change in semantics, is there a better way to do this?
- I've got a few clones where I don't know if I need them (like turning `item` into a `TokenStream`), can these be avoided?
- Is switching to `MultiItemDecorator` the right thing here?

Also fixes https://github.com/rust-lang/rust/issues/37563.

Vendor all rustbuild dependencies in this repo

This commit vendors all crates.io dependencies into the rust-lang/rust repository using the `cargo-vendor` tool. This is done in an effort to make rustbuild distro-ready by ensuring that our source tarballs are self-contained units which don't need extraneous network downloads.

A new `src/vendor` directory is created with all vendored crates, and Cargo, when using rustbuild, is configured to use this directory. Over time we can deduplicate this directory with the actual src tree (e.g. src/librustc_serialize, src/liblibc, src/libgetopts, ...). For now though that's left to a separate commit.

Document convention for using both fmt::Write and io::Write

Using a trait's methods (like `Write::write_fmt` as used in `writeln!` and other macros) requires importing that trait directly (not just the module containing it).  Both `fmt::Write` and `io::Write` provide compatible `Write::write_fmt` methods, and code can use `writeln!` and other macros on both an object implementing `fmt::Write` (such as a `String`) and an object implementing `io::Write` (such as `Stderr`).  However, importing both `Write` traits produces an error due to the name conflict.

The convention I've seen renames both of them on import, to `FmtWrite` and `IoWrite` respectively.  Document that convention in the Rust documentation for `write!` and `writeln!`, with examples.

Clarify that send_to might panic in certain cases

Closes #34202

r? @alexcrichton

Point to type argument span when used as trait

Given the following code:

``` rust
struct Foo<T: Clone>(T);

use std::ops::Add;

impl<T: Clone, Add> Add for Foo<T> {
  type Output = usize;

  fn add(self, rhs: Self) -> Self::Output {
    unimplemented!();
  }
}
```

present the following output:

``` nocode
error[E0404]: `Add` is not a trait
 --> file3.rs:5:21
  |
5 | impl<T: Clone, Add> Add for Okok<T> {
  |                ---  ^^^ expected trait, found type parameter
  |                |
  |                type parameter defined here
```

Fixes #35987.

Include type of missing trait methods in error

Provide either a span pointing to the original definition of missing
trait items, or a message with the inferred definitions.

Fixes #24626. Follow up to PR #36371.

If PR #37369 lands, missing trait items that present a multiline span will be able to show the entirety of the item definition on the error itself, instead of just the first line.

rustdoc: mark unsafe fns in module page with superscript icons

Note: I'v changed the mark style. Now use superscript ⚠(U+26A0) (the old one is '[Unsafe]' literal).
Basically per https://botbot.me/mozilla/rust-docs/2016-10-19/?msg=75112017&page=1

![unsafe-fn-icon](https://cloud.githubusercontent.com/assets/346530/19633650/7f6e1eea-99e6-11e6-8d09-31aec83e46a5.png)

![unsafe-fn](https://cloud.githubusercontent.com/assets/346530/19472050/39daded2-9558-11e6-9148-3cb12afd1c9a.png)

Replace FNV with a faster hash function.

Hash table lookups are very hot in rustc profiles and the time taken within `FnvHash` itself is a big part of that. Although FNV is a simple hash, it processes its input one byte at a time. In contrast, Firefox has a homespun hash function that is also simple but works on multiple bytes at a time. So I tried it out and the results are compelling:

```
futures-rs-test  4.326s vs  4.212s --> 1.027x faster (variance: 1.001x, 1.007x)
helloworld       0.233s vs  0.232s --> 1.004x faster (variance: 1.037x, 1.016x)
html5ever-2016-  5.397s vs  5.210s --> 1.036x faster (variance: 1.009x, 1.006x)
hyper.0.5.0      5.018s vs  4.905s --> 1.023x faster (variance: 1.007x, 1.006x)
inflate-0.1.0    4.889s vs  4.872s --> 1.004x faster (variance: 1.012x, 1.007x)
issue-32062-equ  0.347s vs  0.335s --> 1.035x faster (variance: 1.033x, 1.019x)
issue-32278-big  1.717s vs  1.622s --> 1.059x faster (variance: 1.027x, 1.028x)
jld-day15-parse  1.537s vs  1.459s --> 1.054x faster (variance: 1.005x, 1.003x)
piston-image-0. 11.863s vs 11.482s --> 1.033x faster (variance: 1.060x, 1.002x)
regex.0.1.30     2.517s vs  2.453s --> 1.026x faster (variance: 1.011x, 1.013x)
rust-encoding-0  2.080s vs  2.047s --> 1.016x faster (variance: 1.005x, 1.005x)
syntex-0.42.2   32.268s vs 31.275s --> 1.032x faster (variance: 1.014x, 1.022x)
syntex-0.42.2-i 17.629s vs 16.559s --> 1.065x faster (variance: 1.013x, 1.021x)
```

(That's a stage1 compiler doing debug builds. Results for a stage2 compiler are similar.)

The attached commit is not in a state suitable for landing because I changed the implementation of FnvHasher without changing its name (because that would have required touching many lines in the compiler). Nonetheless, it is a good place to start discussions.

Profiles show very clearly that this new hash function is a lot faster to compute than FNV. The quality of the new hash function is less clear -- it seems to do better in some cases and worse in others (judging by the number of instructions executed in `Hash{Map,Set}::get`).

CC @brson, @arthurprs

Print more tags in rustdoc

r? @steveklabnik

cc @frewsxcv

A little screenshot:

<img width="1440" alt="screen shot 2016-10-13 at 01 41 53" src="https://cloud.githubusercontent.com/assets/3050060/19331745/873cd71e-90e6-11e6-88f8-715668366a3f.png">

Partially stabilize RFC 1506 "Clarify relationships between ADTs"

Lifted restrictions on tuple structs/variants are stabilized, i.e. `S{..}` can be used with any structs and empty tuple structs are permitted without feature gate.
Numeric fields in struct expressions/patterns `S { 0: a, 1: b }` are **NOT** stabilized.
This was implemented 1.5 months ago in Rust 1.12, but this is a tiny technical change that could probably go even without RFC/stabilization period.

cc https://github.com/rust-lang/rust/issues/35626 https://github.com/rust-lang/rust/pull/36871
r? @nikomatsakis

Reword error when data-less enum variant called as function

Given a file like:

``` rust
enum Test {
    Variant,
    Variant2 {a: u32},
}

fn main(){
    let x = Test::Variant("Hello");
    let y = Test::Variant2("World");
}
```

Both errors now look similar:

``` bash
error[E0423]: `Test::Variant2` is the name of a struct or struct variant, but this expression uses it like a function name
  --> file3.rs:10:13
   |
10 |     let y = Test::Variant2("Hello");
   |             ^^^^^^^^^^^^^^ struct called like a function
   |
   = help: did you mean to write: `Test::Variant2 { /* fields */ }`?

error: `Test::Variant` is the name of a data-less enum, but this expression uses it like a function name
 --> file3.rs:9:13
  |
9 |     let x = Test::Variant("World");
  |             ^^^^^^^^^^^^^^^^^^^^^^ data-less enum called like a function
  |
  = help: did you mean to write: `Test::Variant`?
note: defined here
 --> file3.rs:2:5
  |
2 |     Variant,
  |     ^^^^^^^

error: aborting due to previous error
```

Re: #28533

Rollup of 8 pull requests

- Successful merges: #35102, #37425, #37483, #37588, #37601, #37610, #37650, #37652
- Failed merges:

rustbuild: Fix dependencies of check-error-index

This depends on the error index actually existing rather than just the tool to
generate the error index.

Closes #34202

Given the following code:

```rust
struct Foo<T: Clone>(T);

use std::ops::Add;

impl<T: Clone, Add> Add for Foo<T> {
    type Output = usize;

    fn add(self, rhs: Self) -> Self::Output {
      unimplemented!();
    }
}
```

present the following output:

```nocode
error[E0404]: `Add` is not a trait
 --> file3.rs:5:21
  |
5 | impl<T: Clone, Add> Add for Okok<T> {
  |                ---  ^^^ expected trait, found type parameter
  |                |
  |                type parameter defined here
```

If it ran too soon there wasn't a `test` directory lying around but we'll need
one!

More proeminent warning in Arc::{strong,weak}_count docs.

CC https://github.com/rust-lang/rust/issues/28356#issuecomment-259212258

Add missing urls for Sum and Product traits

r? @steveklabnik

Add unary and binary tests for incr-comp

This is my draft of tests for unary and binary expressions as desired by #37520 for use in the test suite for hashes in incremental compilation. Feedback would be wonderful, if there's any changes I need to make I would appreciate the code review.

?r @michaelwoerister

book: Removed platform compatibility table, link to the forge

The content is duplicated, and it doesn't need to be in this location.
It's mostly trivia that doesn't apply to most of the audience.

The forge is up to date.

r? @steveklabnik cc @alexcrichton

Add missing urls on io structs

r? @steveklabnik

Match guessing game output to newest language version

Cargo now informs that it has finished, and there is new error format.

Add error note to illegal code snippet

Mark intentionally invalid code snippet in documentation as such with a comment. Similar comments used elsewhere in this file.

r? @steveklabnik

Make it clear that the reference isn't normative

Any time someone edits the reference, it has to be taken very seriously,
since it's the closest thing we have to a specification. This commit
adds language which indicates that this is not a normative document,
which makes it easier to make tweaks without worrying about forever
harming the future of Rust by painting ourselves in a corner.

r? @aturon

Add `{into,from}_raw` to Rc and Arc

These methods convert to and from a `*const T` for `Rc` and `Arc` similar to the way they work on `Box`. The only slight complication is that `from_raw` needs to offset the pointer back to find the beginning of the `RcBox`/`ArcInner`.

I felt this is a fairly small addition, filling in a gap (when compared to `Box`) so it wouldn't need an RFC. The motivation is primarily for FFI.

(I'll create an issue and update a PR with the issue number if reviewers agree with the change in principle **Edit: done #37197**)

~~Edit: This was initially `{into,from}_raw` but concerns were raised about the possible footgun if mixed with the methods of the same name of `Box`.~~

Edit: This was went from `{into,from}_raw` to `{into,from}_inner_raw` then back to `{into,from}_raw` during review.

Avoid a reallocation in CString::from and CStr::to_owned.

A few changes are included here:

* The `winapi` and `url` dependencies were dropped. The source code for these
  projects is pretty weighty, and we're about to vendor them, so let's not
  commit to that intake just yet. If necessary we can vendor them later but for
  now it shouldn't be necessary.

* The `--frozen` flag is now always passed to Cargo, obviating the need for
  tidy's `cargo_lock` check.

* Tidy was updated to not check the vendor directory

Closes #34687