--wip-- [skip ci]

get the generic text and put it int he suggestion, but suggestion not working on derive subdiagnostic

refactor away from derives and use span_suggestion() instead. Show's the correct(?) generic contents, but overwrites the fn name :(

x fmt

drop commented code and s/todo/fixme

get the correct diagnostic for functions, at least

x fmt

remove some debugs

remove format

remove debugs

remove useless change

remove useless change

remove legacy approach

correct lookahead + error message contains the ident name

fmt

refactor code

tests

add tests

remoev debug

remove comment

Co-authored-by: Takayuki Maeda <takoyaki0316@gmail.com>

Co-authored-by: Jakub Beránek <berykubik@gmail.com>

…66_fix, r=TaKO8Ki

 Suggest fix for misplaced generic params on fn item rust-lang#103366

fixes rust-lang#103366

This still has some work to go, but works for 2/3 of the initial base cases described in #1033366

simple fn:
```
error: expected identifier, found `<`
 --> shreys/test_1.rs:1:3
  |
1 | fn<T> id(x: T) -> T { x }
  |   ^ expected identifier
  |
help: help: place the generic parameter list after the function name:
  |
1 | fn id<T>(x: T) -> T { x }
  |    ~~~~

```

Complicated bounds
```
error: expected identifier, found `<`
 --> spanishpear/test_2.rs:1:3
  |
1 | fn<'a, B: 'a + std::ops::Add<Output = u32>> f(_x: B) { }
  |   ^ expected identifier
  |
help: help: place the generic parameter list after the function name:
  |
1 | fn f<'a, B: 'a + std::ops::Add<Output = u32>>(_x: B) { }
  |    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
```

Opening a draft PR for comments on approach, particularly I have the following questions:
 -  [x]  Is it okay to be using `err.span_suggestion` over struct derives? I struggled to get the initial implementation (particularly the correct suggestion message) on struct derives, although I think given what I've learned since starting, I could attempt re-doing it with that approach.
  -  [x] in the case where the snippet cannot be obtained from a span, is the `help` but no suggestion okay? I think yes (also, when does this case occur?)
  -  [x] are there any red flags for the generalisation of this work for relevant item kinds (i.e. `struct`, `enum`, `trait`, and `union`). My basic testing indicates it does work for those types except the help tip is currently hardcoded to `after the function name` - which should change dependent on the item.
  - [x] I am planning to not show the suggestion if there is already a `<` after the item identifier, (i.e. if there are already generics, as after a function name per the original issue). Any major objections?
  - [x] Is the style of error okay? I wasn't sure if there was a way to make it display nicer, or if thats handled by span_suggestion

These aren't blocking questions, and I will keep working on:
  - check if there is a `<` after the ident (and if so, not showing the suggestion)
  - generalize the help message
  - figuring out how to write/run/etc ui tests (including reading the docs for them)
  - logic cleanups

…compiler-errors

Suggest the correct array length on mismatch

Fixes rust-lang#107156

I wasn't able to find a way to get the `Span` for the actual array size unfortunately, so this suggestion can't be applied automatically.

`@rustbot` label +A-diagnostics

Update the minimum external LLVM to 14

With this change, we'll have stable support for LLVM 14 through 16 (pending release).
For reference, the previous increase to LLVM 13 was rust-lang#100460.

Fix `x fix` on the standard library itself

Fixes rust-lang#107501

…imulacrum

Store metrics from `metrics.json` to CI PGO timer

With this change, we'll be able to easily see how long does it take to compile LLVM vs `rustc`.

r? `@Mark-Simulacrum`

…rister

Fix unintentional UB in ui tests

``@matthiaskrgr`` found UB in a bunch of the ui tests. This PR fixes a batch of miscellaneous tests I didn't think needed reviewers from a particular part of the project.

…mpiler-errors

Avoid ICE when the generic_span is empty

Fixes rust-lang#107998
r? ``@TaKO8Ki``

…orkingjubilee

Shrink size of array benchmarks

Might've overdone it with the size of these benchmarks, as there's no need for them to be quite as large.

Fixes rust-lang#108011