Co-authored-by: Josh Stone <jistone@redhat.com>

…getters a bit

- rename mutating functions to be more scary
- add a new raw bytes getter

when it is the default value of a generic param

…d` ordering, which breaks incremental compilation.

Arrays, surprisingly, are not sized to u64 on all platforms.

Fixes rust-lang#110696

Fixes rust-lang#121472

Fixes rust-lang#112823

Fixes rust-lang#112824

…of.rs

Fixes rust-lang#113017

…tes_of.rs

fixes rust-lang#119275

Some of the marker statements used by coverage are added during MIR building
for use by the InstrumentCoverage pass (during analysis), and are not needed
afterwards.

Experimental feature postfix match

This has a basic experimental implementation for the RFC postfix match (rust-lang/rfcs#3295, rust-lang#121618). [Liaison is](https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/Postfix.20Match.20Liaison/near/423301844) ```@scottmcm``` with the lang team's [experimental feature gate process](https://github.com/rust-lang/lang-team/blob/master/src/how_to/experiment.md).

This feature has had an RFC for a while, and there has been discussion on it for a while. It would probably be valuable to see it out in the field rather than continue discussing it. This feature also allows to see how popular postfix expressions like this are for the postfix macros RFC, as those will take more time to implement.

It is entirely implemented in the parser, so it should be relatively easy to remove if needed.

This PR is split in to 5 commits to ease review.

1. The implementation of the feature & gating.
2. Add a MatchKind field, fix uses, fix pretty.
3. Basic rustfmt impl, as rustfmt crashes upon seeing this syntax without a fix.
4. Add new MatchSource to HIR for Clippy & other HIR consumers

…r=davidtwco

Gracefully handle `AnonConst` in `diagnostic_hir_wf_check()`

Instead of running the WF check on the `AnonConst` itself we run it on the `ty` of the generic param of which the `AnonConst` is the default value.

Fixes rust-lang#122199

…li-obk

interpret/allocation: fix aliasing issue in interpreter and refactor getters a bit

That new raw getter will be needed to let Miri pass pointers to natively executed FFI code ("extern-so" mode).

While doing that I realized our get_bytes_mut are named less scary than get_bytes_unchecked so I rectified that. Also I realized `mem_copy_repeatedly` would break if we called it for multiple overlapping copies so I made sure this does not happen.

And I realized that we are actually [violating Stacked Borrows in the interpreter](https://rust-lang.zulipchat.com/#narrow/stream/136281-t-opsem/topic/I.20think.20Miri.20violates.20Stacked.20Borrows.20.F0.9F.99.88).^^ That was introduced in rust-lang#87777.

r? ```@oli-obk```

coverage: Clean up marker statements that aren't needed later

Some of the marker statements used by coverage are added during MIR building for use by the InstrumentCoverage pass (during analysis), and are not needed afterwards.

```@rustbot``` label +A-code-coverage

…Amanieu

Add `NonNull::<[T]>::is_empty`.

As per rust-lang#71146 (comment)

I figured this should be fine to be insta-stable (with an FCP), but I can edit if that is not desired.

r? ```@Amanieu```

Stop using `<DefId as Ord>` in various diagnostic situations

work towards rust-lang#90317

Reverts part of rust-lang#106281, as it sorts constants and that's problematic since it can contain `ParamConst`, which contains `DefId`s

…ack-workaround-on-overflow, r=TaKO8Ki

Suggest `RUST_MIN_STACK` workaround on overflow

For some Rust crates, like p384, we can't do a whole lot about it even if the stack overflow is reported like in rust-lang#122357 because the problem may be inside LLVM or another codegen backend. We can, however, suggest people set a new `RUST_MIN_STACK` value while handling the SIGSEGV, as that stack-setting will carry forward into the dylib.

As a bonus, this also leads to cleaning up the stack-setting code a bit.

…inism, r=compiler-errors

Fix Itanium mangling usizes

Arrays, surprisingly, are not sized to u64 on all platforms.

Fixes rust-lang#122851.

r? ```@compiler-errors```

cc ```@maurer```

add more ice tests

fixes rust-lang#119275
fixes rust-lang#113017
fixes rust-lang#112824
fixes rust-lang#112823
fixes rust-lang#121472
fixes rust-lang#110696