HirIdification: kill off NodeId stragglers
The final stages of HirIdification (#57578).
This PR, along with https://github.com/rust-lang/rust/pull/59042, should finalize the HirIdification process (at least the more straightforward bits).
- replace `NodeId` with `HirId` in `trait_impls`
- remove all `NodeId`s from `borrowck`
- remove all `NodeId`s from `typeck`
- remove all `NodeId`s from `mir`
- remove `trait_auto_impl` (unused)
I would be cool to also remove `NodeId` from `hir::def::Def`, `middle::privacy::AccessLevel` and `hir::ItemId`, but I don't know if this is feasible.
I'll be happy to do more if I've missed anything.
disallow `#[repr(C)] and `#[repr(packed)]` on structs implementing DispatchFromDyn because they will change the ABI from Scalar/ScalarPair to Aggregrate, resulting in an ICE during object-safety checks or codegen
Rename `CoerceSized` to `DispatchFromDyn`, and reverse the direction so that, for example, you write
```
impl<T: Unsize<U>, U> DispatchFromDyn<*const U> for *const T {}
```
instead of
```
impl<T: Unsize<U>, U> DispatchFromDyn<*const T> for *const U {}
```
this way the trait is really just a subset of `CoerceUnsized`.
The checks in object_safety.rs are updated for the new trait, and some documentation and method names in there are updated for the new trait name — e.g. `receiver_is_coercible` is now called `receiver_is_dispatchable`. Since the trait now works in the opposite direction, some code had to updated here for that too.
I did not update the error messages for invalid `CoerceSized` (now `DispatchFromDyn`) implementations, except to find/replace `CoerceSized` with `DispatchFromDyn`. Will ask for suggestions in the PR thread.
For now, all of the receivers that we care about are just a newtyped
pointer — i.e. `Box<Self>`, `Rc<Self>`, `Pin<Box<Self>>`, `Pin<&mut
Self>`. This is much simpler to implement in codeine than the more
general case, because the ABI is the same as a pointer. So we add some
checks in typeck/coherence/builtin.rs to make sure that implementors of
CoerceSized are just newtyped pointers. In this commit, we also
implement the codegen bits.
Mazdak Farrokhzad
Camille GILLOT
Andy Russell
Mark Rousskov
Guillaume Gomez
varkor
ljedrz
Jeremy Stucki
Eduard-Mihai Burtescu
Tim Diekmann
bors
Alexander Regueiro
John Kåre Alsaker
scalexm
Michael Hewson
Matthias Krüger
Niko Matsakis
csmoe
Vadim Petrochenkov