ensure all packages in Cargo.lock will be vendored, and fail if the
source packages isn't whitelisted.

Reach the body of functions returning `impl Trait` but don't treat it as public

fixes #52128

r? @pnkfelix

cc @EddyB

Update clippy and rls

r? @Manishearth

cc @kennytm @nrc

Removed the promotable field from CheckCrateVisitor...

and replaced it with the custom enum Promotability.

r? @oli-obk

Removed the promotable field from CheckCrateVisitor and replaced it with the structs Promotable and NotPromotable.

rustc: Tweak expansion of #[proc_macro] for 2018

The syntactical expansion of `#[proc_macro]` and related attributes currently
contains absolute paths which conflicts with a lint for the 2018 edition,
causing issues like #52214. This commit puts a band-aid on the issue by ensuring
that procedural macros can also migrate to the 2018 edition for now by tweaking
the expansion based on what features are activated. A more long-term solution
would probably tweak the edition hygiene of spans, but this should do the trick
for now.

Closes #52214

Revert #52212 (revert set opt-level = 3)

Setting -O3 causes LLVM to spuriously segfault at least on Linux. This PR reverts to -O2.

cc #52378

Remove most of `PartialEq` and `Hash` impls from AST and HIR structures

Continuation of https://github.com/rust-lang/rust/pull/49326, prerequisite for removing `PartialEq` for `Ident`.

This reverts commit 1731f0af, reversing
changes made to 0a8275f8.

Set opt-level = 3 the third time.

This PR reverts #51165 (set -O2 for fixing #50867),
which reverted #50329 (set -O3),
which was second attempt of #48204 (set -O3, closed due to Windows segfault that is fixed now),
which reverted #42123 (set -O2 to fix spurious Windows segfaults),
which reverted #41967 (set -O3).

Since we have found the root cause of #50867, this optimization could be tried again.

Last time we've found that setting -O3 regressed the wall time of NLL (https://github.com/rust-lang/rust/pull/50329#issuecomment-388084894), so we may need another perf run to confirm. I'd like to check this *after* the LLVM 7 upgrade #51966 has been merged, so marking this as <kbd>S-blocked</kbd> for now.

Don't display default generic parameters in diagnostics that compare types

In errors like:
```
   expected type: `RawVec<foo, Global>`
      found type: `foo`
```

`RawVec` being defined as `RawVec<T, A: Alloc = Global>`, the error is better written as
```
   expected type: `RawVec<foo>`
      found type: `foo`
```

In fact, that is already what happens when `foo` is not an ADT, because in that case, the diagnostic handler doesn't try to highlight something, and just uses the `Display` trait instead of its own logic.

e.g.
```
   expected type: `RawVec<usize>`
      found type: `usize`
```

proc_macro: Fix crate root detection

Fixes https://github.com/rust-lang/rust/issues/52270

Fix ICE when using a pointer cast as array size

Fixes #52023. I'm not sure if the comment https://github.com/rust-lang/rust/issues/52023#issuecomment-402402392 suggested we also emit `E0080`, but just emitting `E0018` seems reasonable for now.

r? @oli-obk

Add the `amdgpu-kernel` ABI.

Technically, there are requirements imposed by the LLVM
`AMDGPUTargetMachine` on functions with this ABI (eg, the return type
must be void), but I'm unsure exactly where this should be enforced.

Technically, there are requirements imposed by the LLVM
`AMDGPUTargetMachine` on functions with this ABI (eg, the return type
must be void), but I'm unsure exactly where this should be enforced.

Preliminary work for incremental ThinLTO.

Since implementing incremental ThinLTO is a bit more involved than I initially thought, I'm splitting out some of the things that already work. This PR (1) adds a way accessing some ThinLTO information in `rustc` and (2) does some cleanup around CGU/object file naming (which makes things quite a bit nicer).

This is probably best reviewed one commit at a time.

Rollup of 17 pull requests

Successful merges:

 - #51962 (Provide llvm-strip in llvm-tools component)
 - #52003 (Implement `Option::replace` in the core library)
 - #52156 (Update std::ascii::ASCIIExt deprecation notes)
 - #52280 (llvm-tools-preview: fix build-manifest)
 - #52290 (Deny bare trait objects in src/librustc_save_analysis)
 - #52293 (Deny bare trait objects in librustc_typeck)
 - #52299 (Deny bare trait objects in src/libserialize)
 - #52300 (Deny bare trait objects in librustc_target and libtest)
 - #52302 (Deny bare trait objects in the rest of rust)
 - #52310 (Backport 1.27.1 release notes to master)
 - #52315 (Resolve FIXME(#27942))
 - #52316 (task: remove wrong comments about non-existent LocalWake trait)
 - #52322 (Update llvm-rebuild-trigger in light of LLVM 7 upgrade)
 - #52330 (Don't silently ignore invalid data in target spec)
 - #52333 (CI: Enable core dump on Linux, and print their stack trace on segfault. )
 - #52346 (Fix typo in improper_ctypes suggestion)
 - #52350 (Bump bootstrap compiler to 1.28.0-beta.10)

Failed merges:

r? @ghost

Bump bootstrap compiler to 1.28.0-beta.10

r? @Mark-Simulacrum

Fix typo in improper_ctypes suggestion

closes #52345

CI: Enable core dump on Linux, and print their stack trace on segfault.

Don't silently ignore invalid data in target spec

This is technically a breaking change, but only because invalid data was previously silently being ignored.

Update llvm-rebuild-trigger in light of LLVM 7 upgrade

Not triggering a LLVM rebuild [since the LLVM 7 upgrade](https://github.com/rust-lang/rust/pull/51966#issuecomment-404624633) causes builds of rustc to fail.

r? @alexcrichton

task: remove wrong comments about non-existent LocalWake trait

~~A `LocalWaker` is specifically `!Send `, and the unsafety comment around
`LocalWaker::new` only specifies that it be safe to call `wake_local`.
One could then accidentally promote a `LocalWaker` into a `Waker`, which
is universally `Send`, simply via `Waker::from(local_waker)`. A
`LocalWaker` the was built expecting to not be `Send`, such as using
`Rc`, could be sent to other threads safely.~~

~~Separately, though somewhat related, `Context` holds a `&LocalWaker`
internally, and exposes a `waker() -> &Waker` method. This simply
transmutes the `&LocalWaker` to `&Waker`, which would be unsound, except
that you can't "send" a `&Waker`, you'd need to clone it first. Since
`UnsafeWake::clone_raw` requires that it return a `Waker`, the transmute
is not unsound. The transmuted `LocalWaker` will be promoted to a
`Waker` correctly.~~

~~That would mean that if `UnsafeWake::clone_raw` were to be changed, such
as returning `Self` instead of `Waker`, this would no longer be sound.
Thus, this also adds a comment to `clone_raw` to remember this.~~

r? @cramertj

Resolve FIXME(#27942)

[related issue](https://github.com/rust-lang/rust/issues/27942)

cc [#44366](https://github.com/rust-lang/rust/issues/44366)

Backport 1.27.1 release notes to master

r? @pietroalbini

Deny bare trait objects in the rest of rust

Add `#![deny(bare_trait_objects)]` to all the modules not covered before (those did not require code changes) that I consider applicable (I left out shims) in order to futureproof them.

Deny bare trait objects in librustc_target and libtest

Enforce `#![deny(bare_trait_objects)]` in `src/librustc_target` and `src/libtest`.

Deny bare trait objects in src/libserialize

Enforce `#![deny(bare_trait_objects)]` in `src/libserialize`.

Deny bare trait objects in librustc_typeck

Enforce `#![deny(bare_trait_objects)]` in `src/librustc_typeck`.

Deny bare trait objects in src/librustc_save_analysis

Enforce `#![deny(bare_trait_objects)]` in `src/librustc_save_analysis`.

llvm-tools-preview: fix build-manifest

r? @alexcrichton

Update std::ascii::ASCIIExt deprecation notes

Fixes #52085

Implement `Option::replace` in the core library

Here is the implementation of the `Option::replace` method. The first step of [the tracking issue #51998](https://github.com/rust-lang/rust/issues/51998).

Provide llvm-strip in llvm-tools component

Shipping this tool gives people reliable way to reduce the generated executable size.

I'm not sure if this strip tool is available from the llvm version current rust is built on. But let's take a look. @japaric