Upgrade bootstrap compiler to 1.12

r? @alexcrichton

Rollup of 20 pull requests

- Successful merges: #35360, #35526, #35809, #35817, #35820, #35824, #35835, #35841, #35842, #35858, #35860, #35861, #35864, #35878, #35879, #35881, #35882, #35889, #35891, #35901
- Failed merges: #35395

Add sublime-rust to CONFIGS.md.

Just noticed it was missing!

r? @steveklabnik

Add reference to `Self` in traits chapter (book)

Addresses #31891

"r? @steveklabnik

Minor type in CONTRIBUTING.md

A single missing article

rustc: Fix outdated comment

cc https://github.com/rust-lang/rust/issues/35870#issuecomment-241282692

r? @EddyB

add example for `Rc::would_unwrap`

Part of #29372

r? @steveklabnik

Fix "Furthermore" Typo in String Docs

It used to say "Furtheremore" instead of "Furthermore".

replace `println!` statements with `assert!`ions in `std::ptr` examples

r? @steveklabnik

replace `Index` example with something more evocative of indexing

r? @steveklabnik

replace `Rem` example with something more evocative

r? @steveklabnik

replace `Mul` example with something more evocative of multiplication

I may have gone a bit overboard on this one. Numbers are fun.

E0435, E0437 & E0438 New Error Format

Part of #35801 , #35802 and #35803
r? @GuillaumeGomez

Hi! Please review the changes.

Fix typos in unix/rwlock.rs

r? @steveklabnik

Update E0424 to the new error format

Fixes #35797.
Part of #35233.

r? @GuillaumeGomez

New format for E0426

Issue #35799 as a part of issue #35233
r? jonathandturner

Err codes

r? @jonathandturner

Updated E0054, E0423 & E0432 to new error format

Fixes #35791, #35796 and #35344, as part of #35233

r? @jonathandturner

Update E0503 to the new format

Fixes #35703
Part of #35233

r? @jonathandturner

replace `BitAnd` example with something more evocative of bitwise AND

Update E0033 to the new error format

Part of #35233

Addresses #35498
"r? @jonathandturner

Updated error message E0388

Fixes #35339 as part of #35233.

r? @GuillaumeGomez

reformat method chain according to ubsan Rustic Style Guide

https://ubsan.github.io/style/

I may have gone a bit overboard on this one. Numbers are fun.

tone down the error message

cstring: avoid excessive growth just to 0-terminate

Based on following what happens in CString::new("string literal"):

1. Using `Into<Vec<u8>>`, a Vec is allocated with capacity exactly equal
   to the string's input length.
2. By `v.push(0)`, the Vec is grown to twice capacity, since it was full.
3. By `v.into_boxed_slice()`, the Vec capacity is shrunk to fit the length again.

If we use `.reserve_exact(1)` just before the push, then we avoid the
capacity doubling that we're going to have to shrink anyway.

Growing by just 1 byte means that the step (2) is less likely to have to
move the memory to a larger allocation chunk, and that the step (3) does
not have to reallocate.

Addresses part of #35838

Check that executable file is in-tree before failing tidy check

I silenced stdout and stderr for ls-files, not sure if that's appropriate (is `make tidy` intended to give debugging information)? Otherwise it prints each file it find to stdout/stderr, which currently prints nothing (only executable files are checked).

I have not done major testing regarding the behavior of ls-files when the file is ignored, but judging by the man page everything should be fine.

I've duplicated the code which makes the path git-friendly from the `Cargo.lock` checking code; I can extract that into a common helper if wanted (it's only two lines).

Fixes #35689.

Fix linker on Solaris/Illumos

This patch provides a fix for the `GnuLinker::export_symbols` function that currently relies on a `--retain-symbols-file` option which is not supported by the Solaris & Illumos linker.

Instead, a [version script](https://www.gnu.org/software/gnulib/manual/html_node/LD-Version-Scripts.html) is used on this platform to achieve the same goal. Here's an example of a similar approach in LLVM's CMake script: https://github.com/llvm-mirror/llvm/blob/master/cmake/modules/AddLLVM.cmake#L88-L94.

Perhaps other platforms like OpenBSD could benefit from this as well. /cc @semarie

A single missing article

Carrier trait (third attempt)

This adds a `Carrier` trait to operate with `?`. The only public implementation is for `Result`, so effectively the trait does not exist, however, it ensures future compatibility for the `?` operator. This is not intended to be used, nor is it intended to be a long-term solution.

Although this exact PR has not been through Crater, I do not expect it to be a breaking change based on putting numerous similar PRs though Crater in the past.

cc:
* [? tracking issue](https://github.com/rust-lang/rust/issues/31436)
* [previous PR](https://github.com/rust-lang/rust/pull/35056)
* [RFC issue](https://github.com/rust-lang/rfcs/issues/1718) for discussion of long-term Carrier trait solutions.

r? @nikomatsakis