…ochenkov

Make privacy visitor use types more (instead of HIR)

r? `@petrochenkov`

This is a prerequisite to normalizing projections, as otherwise we have too many invalid bound vars (hir_ty_to_ty is creating types that have bound vars, but no binder).

The commits are still chaotic, I'm gonna clean them up, but I just wanted to let you know about the general direction and wondering if we could land this before adding normalization, as normalization is where behavioral changes happen, and I'd like to keep that part as minimal as possible.

[context can be found on zulip](https://rust-lang.zulipchat.com/#narrow/stream/315482-t-compiler.2Fetc.2Fopaque-types/topic/weak.20type.20aliases.20and.20privacy)

…iaskrgr

Rollup of 9 pull requests

Successful merges:

 - rust-lang#113026 (Introduce `run-make` V2 infrastructure, a `run_make_support` library and port over 2 tests as example)
 - rust-lang#113671 (Make privacy visitor use types more (instead of HIR))
 - rust-lang#120308 (core/time: avoid divisions in Duration::new)
 - rust-lang#120693 (Invert diagnostic lints.)
 - rust-lang#120704 (A drive-by rewrite of `give_region_a_name()`)
 - rust-lang#120809 (Use `transmute_unchecked` in `NonZero::new`.)
 - rust-lang#120817 (Fix more `ty::Error` ICEs in MIR passes)
 - rust-lang#120828 (Fix `ErrorGuaranteed` unsoundness with stash/steal.)
 - rust-lang#120831 (Startup objects disappearing from sysroot)

r? `@ghost`
`@rustbot` modify labels: rollup

Rollup merge of rust-lang#113671 - oli-obk:normalize_weak_tys, r=petrochenkov

Make privacy visitor use types more (instead of HIR)

r? ``@petrochenkov``

This is a prerequisite to normalizing projections, as otherwise we have too many invalid bound vars (hir_ty_to_ty is creating types that have bound vars, but no binder).

The commits are still chaotic, I'm gonna clean them up, but I just wanted to let you know about the general direction and wondering if we could land this before adding normalization, as normalization is where behavioral changes happen, and I'd like to keep that part as minimal as possible.

[context can be found on zulip](https://rust-lang.zulipchat.com/#narrow/stream/315482-t-compiler.2Fetc.2Fopaque-types/topic/weak.20type.20aliases.20and.20privacy)

…=compiler-errors

Clean up AstConv

Split off from rust-lang#120926 to make it only contain the renaming & (doc) comment updates.
Any changes other than that which have accumulated over time are now part of this PR.
Let's be disciplined ;) Inspired by rust-lang#120926 (comment).

---

* Remove `hir_trait_to_predicates`
  * Unused since rust-lang#113671
* Inline `create_args_for_ast_trait_ref`
  * Only had a single call site
  * Having it as a separate method didn't gain us anything
* Use an if-let guard somewhere to avoid unwrapping
* Avoid explicit trait object lifetimes
  * More legible, stylistic-only (the updated code is 100% semantically identical)
  * Use explicitly elided lifetimes in impl headers, they get elaborated to distinct lifetimes
  * Make use of [object lifetime defaulting](https://doc.rust-lang.org/reference/lifetime-elision.html#default-trait-object-lifetimes) for a trait object type inside of a reference type somewhere
* Use preexisting dedicated method `ItemCtxt::to_ty` over `<dyn AstConv<'_>>::ast_ty_to_ty`
* Use preexisting dedicated method `AstConv::astconv` over explicit coercions
* Simplify the function signature of `create_args_for_ast_path` and of `check_generic_arg_count`
  * In both cases redundant information was passed rendering the call sites verbose and confusing
  * No perf impact (tested in [rust-lang#120926](rust-lang#120926))
* Move diagnostic method `report_ambiguous_associated_type` from `astconv` to `astconv::errors`
  * The submodule `errors` exists specifically for that purpose
  * Use it to keep the main module clean & short

…=compiler-errors

Clean up AstConv

Split off from rust-lang#120926 to make it only contain the renaming & (doc) comment updates.
Any changes other than that which have accumulated over time are now part of this PR.
Let's be disciplined ;) Inspired by rust-lang#120926 (comment).

---

* Remove `hir_trait_to_predicates`
  * Unused since rust-lang#113671
* Inline `create_args_for_ast_trait_ref`
  * Only had a single call site
  * Having it as a separate method didn't gain us anything
* Use an if-let guard somewhere to avoid unwrapping
* Avoid explicit trait object lifetimes
  * More legible, stylistic-only (the updated code is 100% semantically identical)
  * Use explicitly elided lifetimes in impl headers, they get elaborated to distinct lifetimes
  * Make use of [object lifetime defaulting](https://doc.rust-lang.org/reference/lifetime-elision.html#default-trait-object-lifetimes) for a trait object type inside of a reference type somewhere
* Use preexisting dedicated method `ItemCtxt::to_ty` over `<dyn AstConv<'_>>::ast_ty_to_ty`
* Use preexisting dedicated method `AstConv::astconv` over explicit coercions
* Simplify the function signature of `create_args_for_ast_path` and of `check_generic_arg_count`
  * In both cases redundant information was passed rendering the call sites verbose and confusing
  * No perf impact (tested in [rust-lang#120926](rust-lang#120926))
* Move diagnostic method `report_ambiguous_associated_type` from `astconv` to `astconv::errors`
  * The submodule `errors` exists specifically for that purpose
  * Use it to keep the main module clean & short

Rollup merge of rust-lang#122527 - fmease:clean-up-hir-ty-lowering, r=compiler-errors

Clean up AstConv

Split off from rust-lang#120926 to make it only contain the renaming & (doc) comment updates.
Any changes other than that which have accumulated over time are now part of this PR.
Let's be disciplined ;) Inspired by rust-lang#120926 (comment).

---

* Remove `hir_trait_to_predicates`
  * Unused since rust-lang#113671
* Inline `create_args_for_ast_trait_ref`
  * Only had a single call site
  * Having it as a separate method didn't gain us anything
* Use an if-let guard somewhere to avoid unwrapping
* Avoid explicit trait object lifetimes
  * More legible, stylistic-only (the updated code is 100% semantically identical)
  * Use explicitly elided lifetimes in impl headers, they get elaborated to distinct lifetimes
  * Make use of [object lifetime defaulting](https://doc.rust-lang.org/reference/lifetime-elision.html#default-trait-object-lifetimes) for a trait object type inside of a reference type somewhere
* Use preexisting dedicated method `ItemCtxt::to_ty` over `<dyn AstConv<'_>>::ast_ty_to_ty`
* Use preexisting dedicated method `AstConv::astconv` over explicit coercions
* Simplify the function signature of `create_args_for_ast_path` and of `check_generic_arg_count`
  * In both cases redundant information was passed rendering the call sites verbose and confusing
  * No perf impact (tested in [rust-lang#120926](rust-lang#120926))
* Move diagnostic method `report_ambiguous_associated_type` from `astconv` to `astconv::errors`
  * The submodule `errors` exists specifically for that purpose
  * Use it to keep the main module clean & short

…piler-errors

Remove obsolete parameter `speculative` from `instantiate_poly_trait_ref`

In rust-lang#122527 I totally missed that `speculative` has become obsolete with the removal of `hir_trait_to_predicates` / due to rust-lang#113671.

Fixes rust-lang#114635.

r? `@compiler-errors`

Rollup merge of rust-lang#122577 - fmease:speculative-say-what, r=compiler-errors

Remove obsolete parameter `speculative` from `instantiate_poly_trait_ref`

In rust-lang#122527 I totally missed that `speculative` has become obsolete with the removal of `hir_trait_to_predicates` / due to rust-lang#113671.

Fixes rust-lang#114635.

r? `@compiler-errors`

Refactor type visitor walking

r? `@petrochenkov`

pulling out the uncontroversial parts of rust-lang/rust#113671

Refactor type visitor walking

r? `@petrochenkov`

pulling out the uncontroversial parts of rust-lang/rust#113671

Fix validation when lowering `?` trait bounds

Pass the unlowered (`rustc_hir`) polarity to `lower_poly_trait_ref`.

This allows us to actually *validate* that generic args are actually valid on `?Trait` paths. This actually regressed in rust-lang#113671 because that PR changed the behavior where we were inadvertently re-lowering paths as `BoundPolarity::Positive`, which was also coincidentally the only place we were enforcing the generics on `?Trait` paths were correct.

Fix validation when lowering `?` trait bounds

Pass the unlowered (`rustc_hir`) polarity to `lower_poly_trait_ref`.

This allows us to actually *validate* that generic args are actually valid on `?Trait` paths. This actually regressed in rust-lang#113671 because that PR changed the behavior where we were inadvertently re-lowering paths as `BoundPolarity::Positive`, which was also coincidentally the only place we were enforcing the generics on `?Trait` paths were correct.

Rollup merge of rust-lang#132209 - compiler-errors:modifiers, r=fmease

Fix validation when lowering `?` trait bounds

Pass the unlowered (`rustc_hir`) polarity to `lower_poly_trait_ref`.

This allows us to actually *validate* that generic args are actually valid on `?Trait` paths. This actually regressed in rust-lang#113671 because that PR changed the behavior where we were inadvertently re-lowering paths as `BoundPolarity::Positive`, which was also coincidentally the only place we were enforcing the generics on `?Trait` paths were correct.

Refactor type visitor walking

r? `@petrochenkov`

pulling out the uncontroversial parts of rust-lang/rust#113671