Warn when a `#[test]`-like built-in attribute macro is present multiple times.

Fixes #90979.

Rollup of 6 pull requests

Successful merges:

 - #91901 (Remove `in_band_lifetimes` from `rustc_symbol_mangling`)
 - #91904 (Remove `in_band_lifetimes` from `rustc_trait_selection`)
 - #91951 (update stdarch)
 - #91958 (Apply rust-logo class only on default logo)
 - #91972 (link to pref_align_of tracking issue)
 - #91986 (Bump compiler-builtins to 0.1.66)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Bump compiler-builtins to 0.1.66

Adds intrinsics for truncdfsf2 and truncdfsf2vsp on ARM.

r? `@Amanieu`

link to pref_align_of tracking issue

If we are not going to remove this intrinsic (https://github.com/rust-lang/rust/pull/90877), I think we should at least have a place to centralize discussion around it, so here we go. Intrinsics don't have their own separate features and usually we instead use the public method for tracking it, but this one does not have such a method... so the tracking issue is just a regular link. (And then we sue it for the const part as well.)

Apply rust-logo class only on default logo

Fixes #91653.

![image](https://user-images.githubusercontent.com/220205/146138145-a7a62ea6-3205-4bc7-8460-e985284d93ea.png)

Demo: https://rustdoc.crud.net/jsha/hashes/sha2/

r? ``@GuillaumeGomez``

update stdarch

2 commits in d219ad63c5075098fc224a57deb4852b9734327d..0716b22e902207efabe46879cbf28d0189ab7924
2021-12-9 23:50:37 +0000 to 2021-12-14 16:17:57 +0100
 * Fix a bunch of typos ([Fix a bunch of typos stdarch#1267](https://github.com/rust-lang/stdarch/pull/1267))
 * Stabilize armv8 neon instruction set on aarch64 ([Stabilize armv8 neon instruction set on aarch64 stdarch#1266](https://github.com/rust-lang/stdarch/pull/1266))

The update stabilizes armv8 neon instructions on aarch64. #90972

Remove `in_band_lifetimes` from `rustc_trait_selection`

Another one for #91867

Remove `in_band_lifetimes` from `rustc_symbol_mangling`

Helping out with  #91867

Optimize `vec::retain` performance

This simply moves the loops into the inner function which leads to better results.

```
old:

test vec::bench_retain_100000                            ... bench:     203,828 ns/iter (+/- 2,101)
test vec::bench_retain_iter_100000                       ... bench:      63,324 ns/iter (+/- 12,305)
test vec::bench_retain_whole_100000                      ... bench:      42,989 ns/iter (+/- 291)

new:

test vec::bench_retain_100000                            ... bench:      42,180 ns/iter (+/- 451)
test vec::bench_retain_iter_100000                       ... bench:      65,167 ns/iter (+/- 11,971)
test vec::bench_retain_whole_100000                      ... bench:      33,736 ns/iter (+/- 12,404)
```

Measured on x86_64-unknown-linux-gnu, Zen2

Fixes #91497

Include rustc version in `rustc_span::StableCrateId`

`rustc_span::def_id::StableCrateId` is a hash of various data about a crate during compilation. This PR includes the version of `rustc` in the input when computing this hash. From a cursory reading of [RFC 2603](https://rust-lang.github.io/rfcs/2603-rust-symbol-name-mangling-v0.html), this appears to be acceptable within that design.

In order to pass the `mir-opt` and `ui` test suites, this adds new [normalization for hashes and symbol names in `compiletest`](https://github.com/rust-lang/rust/pull/89836/files#diff-03a0567fa80ca04ed5a55f9ac5c711b4f84659be2d0ac4a984196d581c04f76b). These are enabled by default, but we might prefer it to be configurable.

In the UI tests, I had to truncate a significant amount of error annotations in v0 symbols (and maybe some legacy) in order to get the normalization to work correctly. (See https://github.com/rust-lang/rust/issues/90116.)

Closes #85142.

Adds intrinsics for truncdfsf2 and truncdfsf2vsp on ARM.

extend `simplify_type`

might cause a slight perf inprovement and imo more accurately represents what types there are.

considering that I was going to use this in #85048 it seems like we might need this in the future anyways 🤷

Also replace ' with " in rustdoc template

Rollup of 7 pull requests

Successful merges:

 - #91880 (fix clippy::single_char_pattern perf findings)
 - #91885 (Remove `in_band_lifetimes` from `rustc_codegen_ssa`)
 - #91898 (Make `TyS::is_suggestable` check for non-suggestable types structually)
 - #91915 (Add another regression test for unnormalized fn args with Self)
 - #91916 (Fix a bunch of typos)
 - #91918 (Constify `bool::then{,_some}`)
 - #91920 (Use `tcx.def_path_hash` in `ExistentialPredicate.stable_cmp`)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Use `tcx.def_path_hash` in `ExistentialPredicate.stable_cmp`

This avoids a needless query invocation

Constify `bool::then{,_some}`

Note on `~const Drop`: it has no effect when called from runtime functions, when called from const contexts, the trait system ensures that the type can be dropped in const contexts.

Fix a bunch of typos

I hope that none of these files is not supposed to be modified.

FYI, I opened separate PRs for typos in submodules, in the respective repositories
* https://github.com/rust-lang/stdarch/pull/1267
* https://github.com/rust-lang/backtrace-rs/pull/455

Add another regression test for unnormalized fn args with Self

Closes #91899

Make `TyS::is_suggestable` check for non-suggestable types structually

Not sure if I went overboard checking substs in dyn types, etc. Let me know if I should simplify this function.

Fixes #91832

Remove `in_band_lifetimes` from `rustc_codegen_ssa`

See #91867 for more information.

In `compiler/rustc_codegen_ssa/src/coverageinfo/map.rs`, there are several functions with an explicit `'a` lifetime but only a single `&'a self` parameter. These lifetimes should be redundant given lifetime elision, unless the existential `impl Iterator` has weird issues regarding that. Should the redundant lifetimes be removed?

fix clippy::single_char_pattern perf findings

Rollup of 7 pull requests

Successful merges:

 - #90521 (Stabilize `destructuring_assignment`)
 - #91479 (Add `[T]::as_simd(_mut)`)
 - #91584 (Improve code for rustdoc-gui tester)
 - #91886 (core: minor `Option` doc correction)
 - #91888 (Handle unordered const/ty generics for object lifetime defaults)
 - #91905 (Fix source code page sidebar on mobile)
 - #91906 (Removed `in_band_lifetimes` from `library\proc_macro`)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Removed `in_band_lifetimes` from `library\proc_macro`

Issue [#91867](https://github.com/rust-lang/rust/issues/91867)

This is my first try, I followed the instructions given. Fixed all the errors that were thrown while compiling.
Compiled with stage 0,1, and 2 all of them compiled successfully.

Fix source code page sidebar on mobile

Current broken behaviour:

https://user-images.githubusercontent.com/3050060/145984316-35c82353-5bab-4dc6-9ac6-63ea7e5c27d8.mp4

Fixed:

https://user-images.githubusercontent.com/3050060/145984329-8be1127b-d707-424d-ac3c-c1fb3c48a093.mp4

r? `@jsha`

Handle unordered const/ty generics for object lifetime defaults

*feel like I should have a PR description but cant think of what to put here*

r? ```@lcnr```

core: minor `Option` doc correction

Improve code for rustdoc-gui tester

Following advice given in #91391.

It nicely improves the code readability. :)

r? `@jsha`

Add `[T]::as_simd(_mut)`

SIMD-style optimizations are the most common use for `[T]::align_to(_mut)`, but that's `unsafe`.  So these are *safe* wrappers around it, now that we have the `Simd` type available, to make it easier to use.

```rust
impl [T] {
    pub fn as_simd<const LANES: usize>(&self) -> (&[T], &[Simd<T, LANES>], &[T]);
    pub fn as_simd_mut<const LANES: usize>(&mut self) -> (&mut [T], &mut [Simd<T, LANES>], &mut [T]);
}
```

They're `cfg`'d out for miri because the `simd` module as a whole is unavailable there.

Stabilize `destructuring_assignment`

Closes #71126

- [Stabilization report](https://github.com/rust-lang/rust/issues/71126#issuecomment-941148058)
- [Completed FCP](https://github.com/rust-lang/rust/issues/71126#issuecomment-954914819)

`@rustbot` label +F-destructuring-assignment +T-lang
Also needs +relnotes but I don't have permission to add that tag.

Readd track_caller to Result::from_residual

This is a followup on https://github.com/rust-lang/rust/issues/87401 in and an attempt to move the issue towards resolution.

As part of the overhaul of the Try trait we removed the ability for errors to grab location information during propagation via `?` with the builtin `std::result::Result`. The previously linked issue has a fair bit of discussion into the reasons for and against the usage of `#[track_caller]` on the `FromResidual` impl on `Result` that I will do my best to summarize.

---
### For

- https://github.com/rust-lang/rust/issues/87401#issuecomment-915053533: Difficulties with using non `std::result::Result` like types
- https://github.com/rust-lang/rust/issues/87401#issuecomment-978355102: Inconsistency with functionality provided for recoverable (Result) and non-recoverable errors (panic), where panic provides a location and Result does not, pushing some users towards using panic

### Against

- https://github.com/rust-lang/rust/issues/84277#issuecomment-885322833: concern that this will bloat callers that never use this data

---

Personally, I want to quantify the performance / bloat impact of re-adding this attribute, and fully evaluate the pros and cons before deciding if I need to switch `eyre` to have a custom `Result` type, which would also mean I need `try_trait_v2` to be stabilized, cc `@scottmcm.` If the performance impact is minor enough in the general case I think I would prefer that the default `Result` type has the ability to track location information for consistency with `panic` error reporting, and leave it to applications that need particularly high performance to handle the micro optimizations of introducing their own efficient custom Result type or matching manually.

Alternatively, I wonder if the performance penalty on code that doesn't use the location information on `FromResidual` could be mitigated via new optimizations.

See #91867 for more information.

Rollup of 7 pull requests

Successful merges:

 - #90939 (Tweak errors coming from `for`-loop, `?` and `.await` desugaring)
 - #91859 (Iterator::cycle() — document empty iterator special case)
 - #91868 (Use `OutputFilenames` to generate output file for `-Zllvm-time-trace`)
 - #91870 (Revert setting a default for the MACOSX_DEPLOYMENT_TARGET env var for linking)
 - #91881 (Stabilize `iter::zip`)
 - #91882 (Remove `in_band_lifetimes` from `rustc_typeck`)
 - #91940 (Update cargo)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Update cargo

14 commits in 40dc281755137ee804bc9b3b08e782773b726e44..a359ce16073401f28b84840da85b268aa3d37c88
2021-12-06 21:54:44 +0000 to 2021-12-14 18:40:22 +0000
- Support `term.quiet` configuration (rust-lang/cargo#10152)
- Display alias target on 'cargo help <alias>` (rust-lang/cargo#10193)
- delete --host command and message (rust-lang/cargo#10145)
- Improve I/O error message for fingerprint of build script (rust-lang/cargo#10191)
- Explicitly mark aliases in `cargo list`. (rust-lang/cargo#10177)
- Don't emit "executable" JSON field for non-executables. (rust-lang/cargo#10171)
- Move scrape-examples docs to correct section. (rust-lang/cargo#10166)
- Do not suggest source config if nothing to vendor (rust-lang/cargo#10161)
- Bump versions of local deps. (rust-lang/cargo#10155)
- Bump to 0.60.0, update changelog (rust-lang/cargo#10154)
- Fix some profile documentation. (rust-lang/cargo#10153)
- Document lib before bin. (rust-lang/cargo#10172)
- Sync cargo-the-cli version with rustc. (rust-lang/cargo#10178)
- Remove `-Z future-incompat-report` from message displayed to user (rust-lang/cargo#10185)