…share some code

Follow up to e3f2edc

The comment explains it's for `unstable_offset_of`, but `offset_of` is
now stable.

- Sort dependencies and features sections.
- Add `tidy` markers to the sorted sections so they stay sorted.
- Remove empty `[lib`] sections.
- Remove "See more keys..." comments.

Excluded files:
- rustc_codegen_{cranelift,gcc}, because they're external.
- rustc_lexer, because it has external use.
- stable_mir, because it has external use.

When we encounter a `dyn Trait` that isn't object safe, look for its
implementors. If there's one, mention using it directly If there are
less than 9, mention the possibility of creating a new enum and using
that instead.

Account for object unsafe `impl Trait on dyn Trait {}`.  Make a
distinction between public and sealed traits.

Fix rust-lang#80194.

By storing the unparsed values in `Config` and then parsing them within
`run_compiler`, the parsing functions can use the main symbol interner,
and not create their own short-lived interners.

This change also eliminates the need for one `EarlyErrorHandler` in
rustdoc, because parsing errors can be reported by another, slightly
later `EarlyErrorHandler`.

They now only ever contains symbols.

It was added in 51938c6, a commit with
a 7,720 line diff and a one line commit message. Even then the comment
was incorrect; there was a removed a `build_output_filenames` call with
a `&[]` argument in rustdoc, but the commit removed that call. In such a
large commit, it's easy for small errors to occur.

Using `find` and `any` from `std` makes the code shorter and clearer.

Fix: Write access check of `prefix` and `sysconfdir`
when DESTDIR is present.

Improvement: Instead of repeatedly reading `DESTDIR` within
each `fn prepare_dir` usage, read it once and pass it to
the `fn prepare_dir`.

Signed-off-by: onur-ozkan <work@onurozkan.dev>

- The early return can be right at the top.
- The control flow is simplified with `if let`.
- The `collect` isn't necessary.
- The "Unconditionally" comment is erroneously duplicated from
  `check_attr_crate_type`, and can be removed.

For a local pattern with no space between `let` and `(` e.g.:

  let(_a) = 3;

we were previously suggesting this illegal code:

  let_a =3;

After this change the suggestion will instead be:

  let _a =3;

(Note the space after `let`)

If a function incorrectly contains multiple `...` args, and is also not
foreign or `unsafe extern "C"`, only emit the latter error once.

Trying to use C-variadics in a const function would previously fail with
an error like "destructor of `VaListImpl<'_>` cannot be evaluated at
compile-time".

Add an explicit check for const C-variadics to provide a clearer error:
"functions cannot be both `const` and C-variadic".

…en-args, r=GuillaumeGomez

rustdoc: elide cross-crate default generic arguments

Elide cross-crate generic arguments if they coincide with their default.
TL;DR: Most notably, no more `Box<…, Global>` in `std`'s docs, just `Box<…>` from now on.
Fixes rust-lang#80379.

Also helps with rust-lang#44306. Follow-up to rust-lang#103885, rust-lang#107637.

r? `@ghost`

…=wesleywiser

Clean up `compiler/rustc*/Cargo.toml`

Mostly by sorting dependencies, plus some other minor things.

r? `@wesleywiser`

On object safety error, mention new enum as alternative

When we encounter a `dyn Trait` that isn't object safe, look for its implementors. If there's one, mention using it directly If there are less than 9, mention the possibility of creating a new enum and using that instead.

Fix rust-lang#80194.

share some track_caller logic between interpret and codegen

Also move the code that implements the track_caller intrinsics out of the core interpreter engine -- it's just a helper creating a const-allocation, doesn't need to be part of the interpreter core.

Add support for mipsel-unknown-netbsd, 32-bit LE mips.

Rename a few remaining references to abort terminator

Follow up to e3f2edc

…iadic-errors, r=oli-obk

C-variadic error improvements

A couple improvements for c-variadic errors:

1. Fix the bad-c-variadic error being emitted multiple times. If a function incorrectly contains multiple `...` args, and is also not foreign or `unsafe extern "C"`, only emit the latter error once rather than once per `...`.

2. Explicitly reject `const` C-variadic functions. Trying to use C-variadics in a const function would previously fail with an error like "destructor of `VaListImpl<'_>` cannot be evaluated at compile-time". Add an explicit check for const C-variadics to provide a clearer error: "functions cannot be both `const` and C-variadic". This also addresses one of the concerns in rust-lang#44930: "Ensure that even when this gets stabilized for regular functions, it is still rejected on const fn."

…r=oli-obk

More `rustc_interface` cleanups

In particular, following up rust-lang#117268 with more improvement to `--cfg`/`--check-cfg` handling.

r? `@oli-obk`

…larsan68

improve and fix `x install`

Fix: Write access check of `prefix` and `sysconfdir` when DESTDIR is present.

Improvement: Instead of repeatedly reading `DESTDIR` within each `fn prepare_dir` usage, read it once and pass it to the `fn prepare_dir`.

Fixes rust-lang#117203

Some diagnostics improvements of `gen` blocks

These are leftovers from rust-lang#116447

…d-macro, r=estebank

Fix unused variables lint issue for args in macro

Fixes rust-lang#117284
r? ```@estebank```

…Nilstrieb

Fix missing leading space in suggestion

For a local pattern with no space between `let` and `(` e.g.:
```rust
  let(_a) = 3;
```
we were previously suggesting this illegal code:
```rust
  let_a = 3;
```
After this change the suggestion will instead be:
```rust
  let _a = 3;
```
Fixes rust-lang#117380