small refactor to new projection code
extract `eq_term_and_make_canonical_response` into a helper function which also is another guarantee that the expected term does not influence candidate selection for projections.
also change `evaluate_all(vec![single_goal])` to use `evaluate_goal`.
the second commit now also adds a `debug_assert!` to `evaluate_goal`.
Modify primary span label for E0308
Looking at the reactions to https://hachyderm.io/`@ekuber/109622160673605438,` a lot of people seem to have trouble understanding the current output, where the primary span label on type errors talks about the specific types that diverged, but these can be deeply nested type parameters. Because of that we could see "expected i32, found u32" in the label while the note said "expected Vec<i32>, found Vec<u32>". This understandably confuses people. I believe that once people learn to read these errors it starts to make more sense, but this PR changes the output to be more in line with what people might expect, without sacrificing terseness.
Fix#68220.
Use `ObligationCtxt::new_in_snapshot` in `satisfied_from_param_env`
We can evaluate nested `ConstEvaluatable` obligations in an evaluation probe, which will ICE if we use `ObligationCtxt::new`.
Fixes#107474Fixes#106666
r? `@BoxyUwU` but feel free to reassign
cc `@JulianKnodt` who i think added this assertion code
Not sure if the rustdoc test is needed, but can't hurt. They're the same root cause, though.
Skip possible where_clause_object_safety lints when checking `multiple_supertrait_upcastable`
Fix#106247
To achieve this, I lifted the `WhereClauseReferencesSelf` out from `object_safety_violations` and move it into `is_object_safe` (which is changed to a new query).
cc `@dtolnay`
r? `@compiler-errors`
Remove HirId -> LocalDefId map from HIR.
Having this map in HIR prevents the creating of new definitions after HIR has been built.
Thankfully, we do not need it.
Based on https://github.com/rust-lang/rust/pull/103902
Remove `ControlFlow::{BREAK, CONTINUE}`
Libs-API decided to remove these in #102697.
Follow-up to #107023, which removed them from `compiler/`, but a couple new ones showed up since that was merged.
r? libs
Minor tweaks in the new solver
1. `InferCtxt::probe` is not needed in `compute_subtype_goal` and `compute_well_formed_goal`.
2. Add a handful of comments.
3. Add a micro-optimization in `consider_assumption` where we check the def-ids of the assumption and goal match before instantiating any binders.
r? ``@lcnr``
Correct suggestions for closure arguments that need a borrow
Fixes#107301 by dealing with binders correctly
Fixes another issue where we were suggesting adding just `&` when we expected `&mut _` in a closure arg
Use new solver in `evaluate_obligation` query (when new solver is enabled)
(only when `-Ztrait-solver=next`, of course)
... Does this make sense? It seems to me like it should be reasonable, but maybe there's some reason why this is a bad idea.
r? ``@lcnr``
Needs a perf run because I guess this `solver == TraitSolver::Next` check is on a hot path.
Libs-API decided to remove these in #102697.
Follow-up to #107023, which removed them from `compiler/`, but a couple new ones showed up since that was merged.
Compute generator saved locals on MIR
Generators are currently type-checked by introducing a `witness` type variable, which is unified with a `GeneratorWitness(captured types)` whose purpose is to ensure that the auto traits correctly migrate from the captured types to the `witness` type. This requires computing the captured types on HIR during type-checking, only to re-do it on MIR later.
This PR proposes to drop the HIR-based computation, and only keep the MIR one. This is done in 3 steps.
1. During type-checking, the `witness` type variable is never unified. This allows to stall all the obligations that depend on it until the end of type-checking. Then, the stalled obligations are marked as successful, and saved into the typeck results for later verification.
2. At type-checking writeback, `witness` is replaced by `GeneratorWitnessMIR(def_id, substs)`. From this point on, all trait selection involving `GeneratorWitnessMIR` will fetch the MIR-computed locals, similar to what opaque types do. There is no lifetime to be preserved here: we consider all the lifetimes appearing in this witness type to be higher-ranked.
3. After borrowck, the stashed obligations are verified against the actually computed types, in the `check_generator_obligations` query. If any obligation was wrongly marked as fulfilled in step 1, it should be reported here.
There are still many issues:
- ~I am not too happy having to filter out some locals from the checked bounds, I think this is MIR building that introduces raw pointers polluting the analysis;~ solved by a check specific to static variables.
- the diagnostics for captured types don't show where they are used/dropped;
- I do not attempt to support chalk.
cc `@eholk` `@jyn514` for the drop-tracking work
r? `@oli-obk` as you warned me of potential unsoundness
solver comments + remove `TyCtxt::evaluate_goal`
from the `RustcContributor::explore` session yesterday.
This also removes `TyCtxt::evaluate_goal` because to canonicalize you have to use an `InferCtxt` anyways at which point we should just always get people to use `evaluate_root_goal`.
r? ``@spastorino``
ICE in new solver if we see an inference variable
By construction, we do not expect to see any `ty::Infer(ty::TyVar(_))` inference types in the solver (we treat this as ambiguous, since we need to be able to structurally resolve the self type at least one layer to assemble candidates for it). Additionally, since we're doing no freshening, we also don't expect to see any fresh vars of any kind in the solver.
Let's make that an ICE so we can catch any mistakes.
When #107282 lands, we should also ICE there too if we see a non-int/float infer.
r? `@lcnr`
use `LocalDefId` instead of `HirId` in trait resolution to simplify the obligation clause resolution
This commit introduces a refactoring suggested by `@lcnr` to simplify the obligation clause resolution.
This is just the first PR that introduces a type of refactoring, but others PRs will follow this to introduce name changing to change from the variable name from `body_id` to something else.
Fixes https://github.com/rust-lang/rust/issues/104827
Signed-off-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
`@rustbot` r? `@lcnr`
use LocalDefId instead of HirId in trait resolution to simplify
the obligation clause resolution
Signed-off-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Implement some more new solver candidates and fix some bugs
First, fix some bugs:
1. `IndexVec::drain_enumerated(a..b)` does not give us an iterator of index keys + items enumerated from `a..b`, but from `0..(b-a)`... That caused a bug. See first commit for the fix.
2. Implement the `_: Trait` ambiguity hack. I put it in assemble, let me know if it should live elsewhere. This is important, since we otherwise consider `_: Sized` to have no solutions, and nothing passes!
3. Swap `Ambiguity` and `Unimplemented` cases for the new solver. Sorry for accidentally swapping them 😄
4. Check GATs' own predicates during projection confirmation.
Then implement a few builtin traits:
5. Implement `PointerSized`. Pretty independent.
6. Implement `Fn` family of traits for fnptr, fndef, and closures. Closures are currently broken because `FulfillCtxt::relationships` is intentionally left unimplemented. See comment in the test.
r? ```@lcnr```
Rollup of 8 pull requests
Successful merges:
- #106783 (Recover labels written as identifiers)
- #106973 (Don't treat closures from other crates as local)
- #106979 (Document how to get the type of a default associated type)
- #107053 (signal update string representation for haiku.)
- #107058 (Recognise double-equals homoglyph)
- #107067 (Custom MIR: Support storage statements)
- #107076 (Added const-generic ui test case for issue #106419)
- #107091 (Fix broken format strings in `infer.ftl`)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Don't treat closures from other crates as local
fixes#104817
r? `@lcnr`
Specialization can prefer an impl for an opaque type over a blanket impls that also matches. If the blanket impl only applies if an auto-trait applies, we look at the hidden type of the opaque type to see if that implements the auto trait. The hidden type can be a closure or generator, and thus we will end up seeing these types in coherence and have to handle them properly.
Stop using `BREAK` & `CONTINUE` in compiler
Switching them to `Break(())` and `Continue(())` instead.
Entirely search-and-replace, though there's one spot where rustfmt insisted on a reformatting too.
libs-api would like to remove these constants (https://github.com/rust-lang/rust/pull/102697#issuecomment-1385705202), so stop using them in compiler to make the removal PR later smaller.
Switching them to `Break(())` and `Continue(())` instead.
libs-api would like to remove these constants, so stop using them in compiler to make the removal PR later smaller.
Switch to `EarlyBinder` for `item_bounds` query
Part of the work to finish #105779 (also see https://github.com/rust-lang/types-team/issues/78).
Several queries `X` have a `bound_X` variant that wraps the output in `EarlyBinder`. This adds `EarlyBinder` to the return type of the `item_bounds` query and removes `bound_item_bounds`.
r? `@lcnr`
new trait solver: rebase impl substs for gats correctly
you might've caught this while working on projection code, if so then you can close this pr
r? `@lcnr`
Rework some `predicates_of`/`{Generic,Instantiated}Predicates` code
1. Make `instantiate_own` return an iterator, since it's a bit more efficient and easier to work with
2. Remove `bound_{explicit,}_predicates_of` -- these `bound_` methods in particular were a bit awkward to work with since `ty::GenericPredicates` *already* acts kinda like an `EarlyBinder` with its own `instantiate_*` methods, and had only a few call sites anyways.
3. Implement `IntoIterator` for `InstantiatedPredicates`, since it's *very* commonly being `zip`'d together.
Implement some FIXME methods in the new trait solver
Implement just enough of the solver's response logic to make it not ICE.
Also, fix a bug with `no_bound_vars` call failing due to canonical bound vars.
r? `@lcnr`
Consolidate two almost duplicated fn info extraction routines
Moves `extract_callable_info` up to trait selection, because it was being (almost) duplicated fully there for similar diagnostic purposes. This also generalizes the diagnostics we can give slightly (see UI test).
Rollup of 8 pull requests
Successful merges:
- #105526 (libcore: make result of iter::from_generator Clone)
- #106563 (Fix `unused_braces` on generic const expr macro call)
- #106661 (Stop probing for statx unless necessary)
- #106820 (Deprioritize fulfillment errors that come from expansions.)
- #106828 (rustdoc: remove `docblock` class from notable trait popover)
- #106849 (Allocate one less vec while parsing arrays)
- #106855 (rustdoc: few small cleanups)
- #106860 (Remove various double spaces in the libraries.)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Switch to `EarlyBinder` for `const_param_default` and `impl_trait_ref` queries
Part of the work to close#105779 and implement https://github.com/rust-lang/types-team/issues/78.
Several queries `X` have a `bound_X` variant that wraps the output in `EarlyBinder`. This PR adds `EarlyBinder` to the return type of `const_param_default` and `impl_trait_ref`, and removes their `bound_X` variants.
r? `@lcnr`
I encountered an instance where an `FnPtr` implemented a trait, but I was passing an `FnDef`. To
the end user, there is really no way to differentiate each of them, but it is necessary to cast
to the generic function in order to compile. It is thus useful to suggest `as` in the help note,
(even if the Fn output implements the trait).
Rename `Ty::is_ty_infer` -> `Ty::is_ty_or_numeric_infer`
Makes sure people are aware that they may have a type variable *or* an int/float variable.
r? `@oli-obk` https://github.com/rust-lang/rust/pull/106322#issuecomment-1376913539 but I could instead implement your solution, let me know.
(This will conflict with #106322 for now, ignore that 😄)
