This was left as a TODO in rust-lang#92268, and brings the trait more in
line with what was defined in MCP411.

`Assume::visibility` has been renamed to `Assume::safety`, as
library safety is what's actually being assumed; visibility is
just the mechanism by which it is currently checked (this may
change).

ref: rust-lang/compiler-team#411
ref: rust-lang#99571

resolves query instability issues, and probably better for performance

revealed by tests, manually add a panic to test for dead code

…ossible...

- ... when creating diagnostics in rustc_metadata
-  use the error_code! macro
- pass macro output to diag.code()
- use fluent from within manual implementation of SessionDiagnostic
- emit the untested errors in case they occur in the wild
- stop panicking in the probably-not-dead code, add fixme to write test

ref: rust-lang#100726 (comment)

This corrects the `span_with_body` in the case of closures, which was
incorrectly shortened to the `def_span`.

Also briefly document the history of `sys/windows/rand.rs` as they may be relevant to any future changes.

Fuchsia .manifest files do not support a `#` comment syntax. Because of this, if you copy and paste the current example code for this file, and then remove the line you don't need, you still see an error. To make this a bit easier to follow, split this into two code blocks, one for rustc, and one for cargo.

It was added with e08a84a
(actually, it was called `.methods > .stability` at the time) and was
directly nested that way.

But with the switch to `<details>`, the code has changed drastically out from
under it, to the point where you have to go out of your way to actually get
it to render this way, and the result looks overly-tight and weird alongside
the normal version where this code is not reachable.

safe transmute: use `Assume` struct to provide analysis options

This task was left as a TODO in rust-lang#92268; resolving it brings [`BikeshedIntrinsicFrom`](https://doc.rust-lang.org/nightly/core/mem/trait.BikeshedIntrinsicFrom.html) more in line with the API defined in [MCP411](rust-lang/compiler-team#411).

**Before:**
```rust
pub unsafe trait BikeshedIntrinsicFrom<
    Src,
    Context,
    const ASSUME_ALIGNMENT: bool,
    const ASSUME_LIFETIMES: bool,
    const ASSUME_VALIDITY: bool,
    const ASSUME_VISIBILITY: bool,
> where
    Src: ?Sized,
{}
```
**After:**
```rust
pub unsafe trait BikeshedIntrinsicFrom<Src, Context, const ASSUME: Assume = { Assume::NOTHING }>
where
    Src: ?Sized,
{}
```

`Assume::visibility` has also been renamed to `Assume::safety`, as library safety invariants are what's actually being assumed; visibility is just the mechanism by which it is currently checked (and that may change).

r? `@oli-obk`

---

Related:
- rust-lang/compiler-team#411
- rust-lang#99571

…s, r=davidtwco

Migrate rustc_metadata to SessionDiagnostics

Migrate rustc_metadata to SessionDiagnostics.

Part of rust-lang#100717

Compute information about function parameters on THIR

This avoids some manipulation of typeck results while building MIR.

… r=thomcc

Windows RNG: Use `BCRYPT_RNG_ALG_HANDLE` by default

This only changes a small amount of actual code, the rest is documentation outlining the history of this module as I feel it will be relevant to any future issues that might crop up.

The code change is to use the `BCRYPT_RNG_ALG_HANDLE` [pseudo-handle](https://docs.microsoft.com/en-us/windows/win32/seccng/cng-algorithm-pseudo-handles) by default, which simply uses the default RNG. Previously we used `BCRYPT_USE_SYSTEM_PREFERRED_RNG` which has to load the system configuration and then find and load that RNG. I suspect this was the cause of failures on some systems (e.g. due to corrupted config). However, this is admittedly speculation as I can't reproduce the issue myself (and it does seem quite rare even in the wild). Still, removing a possible point of failure is likely worthwhile in any case.

r? libs

…n514

Fix `std::collections::HashSet::drain` documentation

Hi!

`std::collections::HashSet::drain` contains small typo in the docstring.

I didn't read too much about the model of contributing to Rust, so merge this PR or close and fix the typo the right way :)

Thanks for Rust!

…ity, r=notriddle

rustdoc: remove old CSS selector that causes weird spacing

It was added with e08a84a (actually, it was called `.methods > .stability` at the time) and was directly nested that way.

**EDIT**: It is technically reachable code still, but it seems wrong.

## With the old CSS rule still present

https://notriddle.com/notriddle-rustdoc-test/weird-spacing/lib/struct.Foo.html

![image](https://user-images.githubusercontent.com/1593513/188216226-c667c560-d33d-494f-a492-4e0ec3ac0009.png)

## Version 2 (an older version of this PR)

https://notriddle.com/notriddle-rustdoc-test/normal-spacing-2/lib/struct.Foo.html

![image](https://user-images.githubusercontent.com/1593513/188216418-9fcd3109-f1b2-425d-b4fc-0c6b3b54e48e.png)

## Version 3 (with alignment fix for mobile)

https://notriddle.com/notriddle-rustdoc-test/normal-spacing-3/lib/struct.Foo.html

![image](https://user-images.githubusercontent.com/1593513/188223161-0e1ebce7-842f-41cb-8a0c-ae43aedcfccc.png)

Fix unsupported syntax in .manifest file

Fuchsia .manifest files do not support a `#` comment syntax. Because of this, if you copy and paste the current example code for this file, and then remove the line you don't need, you still see an error. To make this a bit easier to follow, split this into two code blocks, one for rustc, and one for cargo.