https://github.com/rust-lang/rust/issues/60532

Use const generics for array impls [part 1]

Part 1 of #61415, following the plan in https://github.com/rust-lang/rust/issues/61415#issuecomment-497922482

Found a way that works 🙃

- uses a never-stable core::array::LengthAtMost32 to bound the impls
- includes a custom error message to avoid mentioning LengthAtMost32 too often
- doesn't use macros for the slice implementations to avoid #62433

Rollup of 4 pull requests

Successful merges:

 - #61883 (`non_ascii_idents` lint (part of RFC 2457))
 - #62042 (Support stability and deprecation checking for all macros)
 - #62213 (rustdoc: set cfg(doctest) when collecting doctests)
 - #62286 (Check if the archive has already been added to avoid duplicates)

Failed merges:

r? @ghost

Check if the archive has already been added to avoid duplicates

This avoids adding archives multiple times, which results in duplicate
objects in the resulting rlib, leading to symbol collision and link
failures. This could happen when crate contains multiple link attributes
that all reference the same archive.

rustdoc: set cfg(doctest) when collecting doctests

Note: This PR builds on top of https://github.com/rust-lang/rust/pull/61199; only the last commit is specific to this PR.

As discussed in https://github.com/rust-lang/rust/pull/61199, we want the ability to isolate items to only when rustdoc is collecting doctests, but we can't use `cfg(test)` because of libcore's `#![cfg(not(test))]`. This PR proposes a new cfg flag, `cfg(doctest)`, specific to this situation, rather than reusing an existing flag. I've isolated it behind a feature gate so that we can contain the effects to nightly only. (A stable workaround that can be used in lieu of `#[cfg(doctest)]` is `#[cfg(rustdoc)] #[doc(hidden)]`, at least once https://github.com/rust-lang/rust/pull/61351 lands.)

Tracking issue: https://github.com/rust-lang/rust/issues/62210

Support stability and deprecation checking for all macros

RELNOTES: Deprecation attributes on macros now have effect.

Fixes https://github.com/rust-lang/rust/issues/34079
Fixes https://github.com/rust-lang/rust/issues/49912
Unblocks https://github.com/rust-lang/rust/pull/62086
Unblocks https://github.com/rust-lang/rust/pull/61000

`non_ascii_idents` lint (part of RFC 2457)

RFC 2457 [declares](https://github.com/rust-lang/rfcs/blob/121bbeff500c3274cea22c7e0ca176274d592646/text/2457-non-ascii-idents.md): "A `non_ascii_idents` lint is added to the compiler. This lint is allow by default."

(Part of #55467.)

r? @Manishearth

rustc: Remove `dylib` crate type from most rustc crates

Revival of https://github.com/rust-lang/rust/pull/56987

cc @alexcrichton
r? @michaelwoerister

They always end up interned anyway

Update clippy

r? @ghost

Rollup of 4 pull requests

Successful merges:

 - #61990 (First question mark in doctest)
 - #62379 (Add missing links in Option documentation)
 - #62438 (rustbuild: Cleanup global lint settings)
 - #62455 (name the trait in ambiguous-associated-items fully qualified suggestion)

Failed merges:

r? @ghost

name the trait in ambiguous-associated-items fully qualified suggestion

We have the trait at this point, so we can name it in the error message, rather than using "Trait" as a (potentially confusing) placeholder.

Thanks to Yuki "@JohnTitor" Okushi for pointing out where to look (in the same file) for a closely related issue for ambiguous associated types (as opposed to items; that was #59225, except that one won't be
quite as easy to resolve, because we actually don't have the trait `DefId` at that point).

r? @petrochenkov

rustbuild: Cleanup global lint settings

Lint settings do not depend on `if let Some(target) = target` in any way, so they are moved out of that clause.

Internal lints now respect `RUSTC_DENY_WARNINGS`.

Crate name treatment is cleaned up a bit.

cc https://github.com/rust-lang/rust/pull/61545 @flip1995
r? @Mark-Simulacrum

Add missing links in Option documentation

r? @rust-lang/docs

First question mark in doctest

We have had `?` for `Result`s in doctests for some time, but so far haven't used them in doctests. With this PR, I want to start the de-`unwrap`ping of doctests – and the discussion on where to do so.

There is one downside, which is that the code can no longer be copied into a plain `main()` method, on the other hand, there should be a workable error if one does this.

Now that procedural macros no longer link transitively to libsyntax,
this shouldn't be needed any more! This commit is an experiment in
removing all dynamic libraries from rustc except for librustc_driver
itself. Let's see how far we can get with that!

Add support for pc-relative addressing on 64-bit RISC-V

These changes allow Rust to generate position-independent code on `riscv64` targets with code model `medium`.

Closes: https://github.com/rust-lang/rust/issues/59802
See also: https://github.com/rust-embedded/riscv-rt/issues/25, https://github.com/rust-embedded/wg/issues/218

RFC 2457 declares: "A `non_ascii_idents` lint is added to the
compiler. This lint is allow by default."

We have the trait at this point, so we can name it in the error
message, rather than using "Trait" as a (potentially confusing)
placeholder.

Thanks to Yuki "@JohnTitor" Okushi for pointing out where to look (in
the same file) for a closely related issue for ambiguous associated
types (as opposed to items; that was #59225, except that one won't be
quite as easy to resolve, because we actually don't have the trait
`DefId` at that point).

Rollup of 5 pull requests

Successful merges:

 - #60081 (Refactor unicode.py script)
 - #61862 (Make the Weak::{into,as}_raw methods)
 - #62243 (Improve documentation for built-in macros)
 - #62422 (Remove some uses of mem::uninitialized)
 - #62436 (normalize use of backticks/lowercase in compiler messages for librustc_mir)

Failed merges:

r? @ghost

normalize use of backticks/lowercase in compiler messages for librustc_mir

normalize use of backticks/lowercase in compiler messages for librustc_mir

https://github.com/rust-lang/rust/issues/60532

r? @alexreg

Remove some uses of mem::uninitialized

cc #62397
r? @RalfJung

Improve documentation for built-in macros

This is the `libcore` part of https://github.com/rust-lang/rust/pull/62086.
Right now the only effect is improved documentation.

The changes in the last few commits are required to make the `libcore` change compile successfully.