Given `'hello world'` and `'1 str', provide a structured suggestion for a valid string literal:

```
error[E0762]: unterminated character literal
  --> $DIR/lex-bad-str-literal-as-char-3.rs:2:26
   |
LL |     println!('hello world');
   |                          ^^^^
   |
help: if you meant to write a `str` literal, use double quotes
   |
LL |     println!("hello world");
   |              ~           ~
```
```
error[E0762]: unterminated character literal
  --> $DIR/lex-bad-str-literal-as-char-1.rs:2:20
   |
LL |     println!('1 + 1');
   |                    ^^^^
   |
help: if you meant to write a `str` literal, use double quotes
   |
LL |     println!("1 + 1");
   |              ~     ~
```

Fix rust-lang#119685.

… in 2021 edition

Fixes rust-lang#99945

…01852

Fixes rust-lang#101852

…E: IndexMap: key not found

Fixes rust-lang#104779

…trait system" rust-lang#105047

Fixes rust-lang#105047

Fixes rust-lang#106423

Fixes rust-lang#106444

Fixes rust-lang#106874

Fixes rust-lang#107228

…olnay

Soft-destabilize `RustcEncodable` & `RustcDecodable`, remove from prelude in next edition

cc rust-lang/libs-team#272

Any use of `RustcEncodable` and `RustcDecodable` now triggers a deny-by-default lint. The derives have been removed from the 2024 prelude. I specifically chose **not** to document this in the module-level documentation, as the presence in existing preludes is not documented (which I presume is intentional).

This does not implement the proposed change for `rustfix`, which I will be looking into shortly.

With regard to the items in the preludes being stable, this should not be an issue because rust-lang#15702 has been resolved.

r? libs-api

regression test for rust-lang#103626

I don't know what a descriptive filename for this would be.

Fixes rust-lang#103626

…ody-validation, r=cjgillot

Fix validation on substituted callee bodies in MIR inliner

When inlining a coroutine, we will substitute the MIR body with the args of the call. There is code in the MIR validator that attempts to prevent query cycles, and will use the coroutine body directly when it detects that's the body that's being validated. That means that when inlining a coroutine body that has been substituted, it may no longer be parameterized over the original args of the coroutine, which will lead to substitution ICEs.

Fixes rust-lang#119064

Handle str literals written with `'` lexed as lifetime

Given `'hello world'` and `'1 str', provide a structured suggestion for a valid string literal:

```
error[E0762]: unterminated character literal
  --> $DIR/lex-bad-str-literal-as-char-3.rs:2:26
   |
LL |     println!('hello world');
   |                          ^^^^
   |
help: if you meant to write a `str` literal, use double quotes
   |
LL |     println!("hello world");
   |              ~           ~
```
```
error[E0762]: unterminated character literal
  --> $DIR/lex-bad-str-literal-as-char-1.rs:2:20
   |
LL |     println!('1 + 1');
   |                    ^^^^
   |
help: if you meant to write a `str` literal, use double quotes
   |
LL |     println!("1 + 1");
   |              ~     ~
```

Fix rust-lang#119685.

transmute: caution against int2ptr transmutation

This came up in rust-lang#121282.
Cc ``@saethlin`` ``@scottmcm``

Eventually we'll add a proper description of provenance that we can reference, but that's a bunch of work and it's unclear who will have the time to do that when. Meanwhile, let's at least do what we can without mentioning provenance explicitly.

…r=lcnr

Uniquify `ReError` on input mode in canonicalizer

See test descr

Fixes rust-lang#122861

r? lcnr

Add test in higher ranked subtype

I'm a beginner in this repository, and there are some things I'm not sure about:

- Is it okay that there is a warning:
```
rustc_infer::infer::relate::generalize may incompletely handle alias type: AliasTy { args: [?1t, '^0.Named(DefId(0:15 ~ structually_relate_aliases[de75]::{impl#1}::'a), "'a")], def_id: DefId(0:5 ~ structually_relate_aliases[de75]::ToUnit::Unit) }
```
- Is it okay that there are two duplicate errors in the same line?
- Did I put the test in the right place?

Any suggestions would be appreciated.

Fixes rust-lang#121649

…xxxx, r=fmease

add a couple more ice tests

Fixes rust-lang#104779
Fixes rust-lang#106423
Fixes rust-lang#106444
Fixes rust-lang#101852
Fixes rust-lang#106874
Fixes rust-lang#105047
Fixes rust-lang#107228
Fixes rust-lang#99945