…onCtxt API

Before, the lint did the checking for `must_use` and pretty printing the
types in a special format in one pass, causing quite complex and
untranslatable code.
Now the collection and printing is split in two. That should also make
it easier to translate or extract the type pretty printing in the
future.

Also fixes an integer overflow in the array length pluralization
calculation.

…ect unsound cases

…ence

…lally allow trait resolution to prove false things during coherence

Do not suggest `.clone()` as we already suggest borrowing the iterated
value.

Forbid inlining `thread_local!`'s `__getit` function on Windows

Sadly, this will make things slower to avoid UB in an edge case, but it seems hard to avoid... and really whenever I look at this code I can't help but think we're asking for trouble.

It's pretty dodgy for us to leave this as a normal function rather than `#[inline(never)]`, given that if it *does* get inlined into a dynamically linked component, it's extremely unsafe (you get some other thread local, or if you're lucky, crash). Given that it's pretty rare for people to use dylibs on Windows, the fact that we haven't gotten bug reports about it isn't really that convincing. Ideally we'd come up with some kind of compiler solution (that avoids paying for this cost when static linking, or *at least* for use within the same crate...), but it's not clear what that looks like.

Oh, and because all this is only needed when we're implementing `thread_local!` with `#[thread_local]`, this patch adjusts the `cfg_attr` to be `all(windows, target_thread_local)` as well.

r? `@ChrisDenton`

See also rust-lang#84933, which is about improving the situation.

Add powerpc64-ibm-aix as Tier-3 target

This is part of the effort mentioned in rust-lang/compiler-team#553.

A reference to these options are definitions from [clang](https://github.com/llvm/llvm-project/blob/ad6fe32032a6229e0c40510e9bed419a01c695b3/clang/lib/Basic/Targets/PPC.h#L414-L448) and [llvm](https://github.com/llvm/llvm-project/blob/main/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp).

AIX has a system `ld` but [its options and behaviors](https://www.ibm.com/docs/en/aix/7.3?topic=l-ld-command) are different from GNU ld. Thanks to `@bzEq` for contributing the linking args.

Allow opaque types in trait impl headers and rely on coherence to reject unsound cases

r? `@lcnr`

fixes rust-lang#99840

…ler-errors

Suggest `.clone()` or `ref binding` on E0382

Refactor must_use lint into two parts

Before, the lint did the checking for `must_use` and pretty printing the types in a special format in one pass, causing quite complex and untranslatable code.
Now the collection and printing is split in two. That should also make it easier to translate or extract the type pretty printing in the future.

Also fixes an integer overflow in the array length pluralization
calculation.

fixes rust-lang#104352

…lcnr

Use obligation ctxt instead of dyn TraitEngine

r? `@lcnr`

…r=thomcc

enable fuzzy_provenance_casts lint in liballoc and libstd

r? `@thomcc`

…d-as-const-generic, r=oli-obk

Add failing test for projections used as const generic

Based on the experiment done in rust-lang#104443, we realized it's currently not possible to support projections in const generics. More information about it in rust-lang#104443 (comment).

This PR adds the UI test in any case so we can gather data in order to work towards adding `TyAlias` into the ABI in the future.

r? `@oli-obk`

Speed up mpsc_stress test

See https://rust-lang.zulipchat.com/#narrow/stream/122651-general/topic/mpsc_stress for context

r? windows

…ler-errors

Fix `ClosureKind::to_def_id`

`Fn` and `FnOnce` were mixed up in rust-lang#99131.

…litely, r=compiler-errors

Use `tcx.require_lang_item` instead of unwrapping lang items

I clearly remember esteban telling me that there is `require_lang_item` but he was from a phone atm and I couldn't find it, so I didn't use it. Stumbled on it today, so here we are :)