librustdoc: instead of skipping ignored tests, pass them to libtest
so it can report them as such.  If a test is marked as `notrust`,
however, it will not show up in the final report.

Fix #12939

`RefCell::get` can be a bit surprising, because it actually clones the wrapped value. This removes `RefCell::get` and replaces all the users with `RefCell::borrow()` when it can, and `RefCell::borrow().clone()` when it can't. It removes `RefCell::set` for consistency. This closes #13182.

It also fixes an infinite loop in a test when debugging is on.

Work on #13287 

This is not ready for a merge yet, but I wanted to get some eyes on what I have done so far.

As of right now, all references in the text to managed boxes or pointers are removed. Code associated with those specific sections of text have likewise been altered. I also removed all references to managed closures.

There is a small change I would like to add to the work done in 3137cd5a, on the new lines 1495 and 1496, I would like to change those values to 10 and 20. I did the same in a later change on lines 1596 and 1508.

There are still bits of sample code that use managed pointers and the sigil @. Those are next on my list to remove, but I wanted to have the outstanding changes reviewed first. The uses of @ in the code samples are a bit more embedded, and I will need to be more careful changing them as to not change the purpose of the code examples.

I ensured that make check still passes, although I'm not sure if that actually tests the code in tutorial.md.

One issues I ran into, and tried to avoid, was that `tutorial.md` is formatted with a nice column limit. I was unsure how this was enforced, so wherever I edited a line, I did my best to keep edits on the line they previously existed on. As such, the plain text of `tutorial.md` looks a bit strange as I've left it, and I will clean that up as suggested. The rendered markdown output should not be affected.

rustc: feature-gate `concat_idents!`.

concat_idents! is not as useful as it could be, due to macros only being
allowed in limited places, and hygiene, so lets feature gate it until we
make a decision about it.

cc #13294

This was missed when dropping the null-termination from our string
types. An explicit null byte can still be placed anywhere in a string if
desired, but there's no reason to stick one at the end of every string
constant.

concat_idents! is not as useful as it could be, due to macros only being
allowed in limited places, and hygiene, so lets feature gate it until we
make a decision about it.

cc #13294

These syntax extensions need a place to be documented, and this starts passing a
`--cfg dox` parameter to `rustdoc` when building and testing documentation in
order to document macros so that they have no effect on the compiled crate, but
only documentation.

Closes #5605

- Sort attributes lexicographically
- Use new attribute syntax consistently
- Fix wording describing new attribute syntax
- Expand section on `repr`

librustdoc: instead of skipping ignored tests, pass them to libtest
so it can report them as such.  If a test is marked as `notrust`,
however, it will not show up in the final report.

Fixes #12949.

Mostly around attributes and language items.

This fixes #13238. It avoids an infinite loop when compiling
the tests with `-g`. Without this change, the debuginfo on
`black_box` prevents the method from being inlined, which
allows llvm to convert `silent_recurse` into a tail-call. This
then loops forever instead of consuming all the stack like it
is supposed to. This patch forces inlining `black_box`, which
triggers the right error.

It's surprising that `RefCell::get()` is implicitly doing a clone
on a value. This patch removes it and replaces all users with
either `.borrow()` when we can autoderef, or `.borrow().clone()`
when we cannot.

This also changes some of the download links in the documentation
to 'nightly'.

This is the final commit need to implement [RFC #4](https://github.com/rust-lang/rfcs/blob/master/active/0004-private-fields.md), it makes all tuple struct fields private by default, overridable with the `pub` keyword.

I'll note one divergence from the original RFC which is outlined in the first commit.

This was missed when dropping the null-termination from our string
types. An explicit null byte can still be placed anywhere in a string if
desired, but there's no reason to stick one at the end of every string
constant.

Closes #13285 (rustc: Stop using LLVMGetSectionName)
Closes #13280 (std: override clone_from for Vec.)
Closes #13277 (serialize: add a few missing pubs to base64)
Closes #13275 (Add and remove some ignore-win32 flags)
Closes #13273 (Removed managed boxes from libarena.)
Closes #13270 (Minor copy-editing for the tutorial)
Closes #13267 (fix Option<~ZeroSizeType>)
Closes #13265 (Update emacs mode to support new `#![inner(attribute)]` syntax.)
Closes #13263 (syntax: Remove AbiSet, use one Abi)

This also changes some of the download links in the documentation
to 'nightly'.

These syntax extensions need a place to be documented, and this starts passing a
`--cfg dox` parameter to `rustdoc` when building and testing documentation in
order to document macros so that they have no effect on the compiled crate, but
only documentation.

Closes #5605

examples in relevant sections were similarly altered.

Merging the 0.10 release into the master branch.

This change removes the AbiSet from the AST, converting all usage to have just
one Abi value. The current scheme selects a relevant ABI given a list of ABIs
based on the target architecture and how relevant each ABI is to that
architecture.

Instead of this mildly complicated scheme, only one ABI will be allowed in abi
strings, and pseudo-abis will be created for special cases as necessary. For
example the "system" abi exists for stdcall on win32 and C on win64.

Closes #10049

1778b636 provided the guarantee of no
`exchange_free` calls for ~ZeroSizeType, so a sentinel can now be used
without overhead.

Closes #11998

Note: "different to" is not exactly incorrect, but "different from" is more
commonly accepted in both US and Commonwealth English, and also more
consistent with other usage within this tutorial.

There are actually three traits listed.