rustdoc: Rename `set_back_info` to `restore_module_data`.
Follow-up to #133345, r? `@GuillaumeGomez`
Most of the references to `info` got removed as it was clear that `module_data` makes more sense here. Makes it clearer that `save_module_data` and `restore_module_data` are a pair.
rustdoc-json: Include safety of `static`s
`static`s in an `extern` block can have an associated safety annotation ["because there is nothing guaranteeing that the bit pattern at the static’s memory is valid for the type it is declared with"](https://doc.rust-lang.org/reference/items/external-blocks.html#statics). Rustdoc already knows this and displays in for HTML. This PR also includes it in JSON.
Inspired by https://github.com/obi1kenobi/cargo-semver-checks/issues/975 which needs this, but it's probably useful in other places.
r? `@GuillaumeGomez.` Possibly easier to review commit-by-commit.
rustc_target reexports a lot of things that are in rustc_abi, but
that will be over soon and now is probably a good time to switch.
Uses of rustc_target remain where they inquire about the target tuple.
rustdoc: use strategic boxing to shrink `clean::Item`
* `inline_stmt_id` is never a cross-crate DefId, so save space by not storing it.
* Instead of two inner boxes for `Item`, use one.
Rustdoc often has to special-case `Self` because it is, well, a special
type of generic parameter (although it also behaves as an alias in
concrete impls). Instead of spreading this special-casing throughout the
code base, create a new variant of the `clean::Type` enum that is for
`Self` types.
This is a refactoring that has almost no impact on rustdoc's behavior,
except that `&Self`, `(Self,)`, `&[Self]`, and other similar occurrences
of `Self` no longer link to the wrapping type (reference primitive,
tuple primitive, etc.) as regular generics do. I felt this made more
sense since users would expect `Self` to link to the containing trait or
aliased type (though those are usually expanded), not the primitive that
is wrapping it. For an example of the change, see the docs for
`std::alloc::Allocator::by_ref`.
Rename HIR `TypeBinding` to `AssocItemConstraint` and related cleanup
Rename `hir::TypeBinding` and `ast::AssocConstraint` to `AssocItemConstraint` and update all items and locals using the old terminology.
Motivation: The terminology *type binding* is extremely outdated. "Type bindings" not only include constraints on associated *types* but also on associated *constants* (feature `associated_const_equality`) and on RPITITs of associated *functions* (feature `return_type_notation`). Hence the word *item* in the new name. Furthermore, the word *binding* commonly refers to a mapping from a binder/identifier to a "value" for some definition of "value". Its use in "type binding" made sense when equality constraints (e.g., `AssocTy = Ty`) were the only kind of associated item constraint. Nowadays however, we also have *associated type bounds* (e.g., `AssocTy: Bound`) for which the term *binding* doesn't make sense.
---
Old terminology (HIR, rustdoc):
```
`TypeBinding`: (associated) type binding
├── `Constraint`: associated type bound
└── `Equality`: (associated) equality constraint (?)
├── `Ty`: (associated) type binding
└── `Const`: associated const equality (constraint)
```
Old terminology (AST, abbrev.):
```
`AssocConstraint`
├── `Bound`
└── `Equality`
├── `Ty`
└── `Const`
```
New terminology (AST, HIR, rustdoc):
```
`AssocItemConstraint`: associated item constraint
├── `Bound`: associated type bound
└── `Equality`: associated item equality constraint OR associated item binding (for short)
├── `Ty`: associated type equality constraint OR associated type binding (for short)
└── `Const`: associated const equality constraint OR associated const binding (for short)
```
r? compiler-errors
