implement the skeleton of the updated trait solver
cc ```@rust-lang/initiative-trait-system-refactor```
This is mostly following the architecture discussed in the types team meetup.
After discussing the desired changes for the trait solver, we encountered cyclic dependencies between them. Most notably between changing evaluate to be canonical and returning inference constraints. We cannot canonicalize evaluate without returning inference constraints due to coinductive cycles. However, caching inference constraints also relies on canonicalization. Implementing both of these changes at once in-place is not feasible.
This somewhat closely mirrors the current `evaluate` implementation with the following notable differences:
- it moves `project` into the core solver, allowing us to correctly deal with coinductive projections (will be required for implied bounds, perfect derive)
- it changes trait solver overflow to be non-fatal (required to backcompat breakage from changes to the iteration order of nested goals, deferred projection equality, generally very useful)
- it returns inference constraints and canonicalizes inputs and outputs (required for a lot things, most notably merging fulfill and evaluate, and deferred projection equality)
- it is implemented to work with lazy normalization
A lot of things aren't yet implemented, but the remaining FIXMEs should all be fairly self-contained and parallelizable. If the architecture looks correct and is what we want here, I would like to quickly merge this and then split the work.
r? ```@compiler-errors``` / ```@rust-lang/types``` :3
Mark `proc_macro_decls_static` as always used
This would have avoided a bug in https://github.com/rust-lang/rust/pull/104860.
In practice this shouldn't matter since nothing uses the query other than the `dead_code` lint, but this isn't documented as an internal-only query so it seems nice for it to be accurate. I think for `dead_code` it doesn't matter because the relevant code is generated by `rustc_builtin_macros` and isn't linted.
I think `@tmiasko` or `@bjorn3` would be a good reviewer?
r? `@tmiasko`
Rollup of 6 pull requests
Successful merges:
- #105567 (KCFI test: Also support LLVM 16 output)
- #105847 (Ensure param-env is const before calling `eval_to_valtree`)
- #105983 (Add a missing early return in drop tracking `handle_uninhabited_return`)
- #106027 (rustdoc: simplify CSS and DOM for more-scraped-examples)
- #106035 (Migrate search tab title color to CSS variable)
- #106037 (Add regression test for #94293)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
rustdoc: simplify CSS and DOM for more-scraped-examples
This gets rid of the more-scraped-examples-inner wrapper, instead nesting the children directly and using absolute positioning for the toggle line.
Add a missing early return in drop tracking `handle_uninhabited_return`
This return is needed so we don't call `Ty::is_inhabited_from` from a type with ty/ct vars in it.
Fixes#105981
Ensure param-env is const before calling `eval_to_valtree`
Other queries call `ParamEnv::with_const` *inside* of the query itself (e.g. `const_eval_global_id_for_typeck`), so this could alternatively be moved into the provider of `eval_to_valtree` instead. I don't have a particularly strong opinion, though *theoretically* caching is better if we make the query keys more constrained.
I'm not exactly sure how this is an effect of the `-Zmir-opt-level=3` flag. Maybe something about the inliner causes us to inline an unevaluated const into a body where it can be evaluated, but where it has not yet been normalized.
This seems likely, since we're inlining `from_fn_1::<{ N / 2 }, _>` in `from_fn_2`, which means that we will need to evaluate that constant during the const prop pass after inlining.
Fixes#104396
This would have avoided a bug in https://github.com/rust-lang/rust/pull/104860.
In practice this shouldn't matter since nothing uses the query other than the `dead_code` lint,
but this isn't documented as an internal-only query so it seems nice for it to be accurate.
I think for `dead_code` it doesn't matter because the relevant code is generated by `rustc_builtin_macros` and isn't linted.
Retag as FnEntry on `drop_in_place`
This commit changes the mir drop shim to always retag its argument as if it were a `&mut`.
cc rust-lang/unsafe-code-guidelines#373
Rollup of 8 pull requests
Successful merges:
- #104741 (Switch `#[track_caller]` back to a no-op unless feature gate is enabled)
- #105769 (add function to tell the identical errors for ambiguity_errors)
- #105843 (Suggest associated const on possible capitalization mistake)
- #105966 (Re-enable `Fn` trait call notation error for non-tuple argument)
- #106002 (codegen tests: adapt patterns to also work with v0 symbol mangling)
- #106010 (Give opaque types a better coherence error)
- #106016 (rustdoc: simplify link anchor to section expand JS)
- #106024 (Fix ICE due to `todo!()` in `rustdoc` for `Term`s)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Fix ICE due to `todo!()` in `rustdoc` for `Term`s
Left a todo awhile ago (I think), so fill it in to print a const for `Term`s.
Fixes#105952.
Should I add some annotations to the rustdoc test?
Re-enable `Fn` trait call notation error for non-tuple argument
I have no idea why I delayed this bug... but also there doesn't seem to be a UI test that actually shows a change, so maybe that's why.
Fixes#105936
add function to tell the identical errors for ambiguity_errors
if 2 errors of the kind and ident and span of the ident, b1, b2 and misc1 misc2 are the same we call these 2 ambiguity errors identical
prevent identical ambiguity error from pushing into vector of ambiguity_errors this will fix#105177
Switch `#[track_caller]` back to a no-op unless feature gate is enabled
This patch fixes a regression, in which `#[track_caller]`, which was previously a no-op, was changed to actually turn on the behavior. This should instead only happen behind the `closure_track_caller` feature gate.
Also, add a warning for the user to understand how their code will compile depending on the feature gate being turned on or not.
Fixes#104588
Fix impl block in const expr
Fixes#83026.
The problem was that we didn't visit block expressions. Considering how big the [walk_expr](https://doc.rust-lang.org/nightly/nightly-rustc/src/rustc_hir/intravisit.rs.html#678) function is, I decided to instead implement the `hir` visitor on the struct. It also answers the question which was in a comment for `RustdocVisitor`: we should have used a visitor instead of our ad-hoc implementation.
Adding this visitor also added some extra checks that weren't present before (check changes in `rustdoc-ui` tests).
r? `@notriddle`
Rollup of 8 pull requests
Successful merges:
- #105584 (add assert messages if chunks/windows are length 0)
- #105602 (interpret: add read_machine_[ui]size convenience methods)
- #105824 (str.lines() docstring: clarify that line endings are not returned)
- #105980 (Refer to "Waker" rather than "RawWaker" in `drop` comment)
- #105986 (Fix typo in reading_half_a_pointer.rs)
- #105995 (Add regression test for #96530)
- #106008 (Sort lint_groups in no_lint_suggestion)
- #106014 (Add comment explaining what the scrape-examples-toggle.goml GUI test is about)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Clarify that raw retags are not permitted in Mir
Not sure when this changed, but documentation and the validator needed to be updated. This also removes raw retags from custom mir.
cc rust-lang/miri#2735
r? `@RalfJung`
Don't ICE in `check_must_not_suspend_ty` for mismatched tuple arity
These expressions are just used for their spans, so make it best-effort here.
Fixes#105728
Rename `assert_uninit_valid` intrinsic
It's not about "uninit" anymore but about "filling with 0x01 bytes" so the name should at least try to reflect that.
This is actually not fully correct though, as it does still panic for all uninit with `-Zstrict-init-checks`. I'm not sure what the best way is to deal with that not causing confusion. I guess we could just remove the flag? I don't think having it makes a lot of sense anymore with the direction that we have chose to go. It could be relevant again if #100423 lands so removing it may be a bit over eager.
r? `@RalfJung`
Rollup of 8 pull requests
Successful merges:
- #105791 (docs: add long error explanation for error E0472)
- #105897 (Fix an opaque type ICE)
- #105904 (Fix arch flag on i686-apple-darwin)
- #105949 (Bump `cfg-if` to `1.0` in rustc crates)
- #105964 (rustdoc: prevent CSS layout of line numbers shrinking into nothing)
- #105972 (rustdoc: simplify section anchor CSS)
- #105973 (Avoid going through the happy path in case of non-fn builtin calls)
- #105976 (Remove unused `check-stage2-T-arm-linux-androideabi-H-x86_64-unknown-linux-gnu` make rule)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
