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2020-07-20trait_sel: only test predicates w/ no substsDavid Wood-15/+15
This commit modifies the `substitute_normalize_and_test_predicates` query, renaming it to `impossible_predicates` and only checking predicates which do not require substs. By making this change, polymorphization doesn't have to explicitly support vtables. Signed-off-by: David Wood <david@davidtw.co>
2020-07-17refactor ty_is_non_localBastian Kauschke-15/+18
2020-07-17cleanup ty_is_~non~_local_constructorBastian Kauschke-38/+21
2020-07-17Rename TypeckTables to TypeckResults.Valentin Lazureanu-27/+27
2020-07-17Remove some `Symbol:as_str()` calls.Nicholas Nethercote-2/+2
2020-07-16Rename `sym::item_context` as `sym::ItemContext`.Nicholas Nethercote-4/+4
Because it represents the symbol `ItemContext`, and `sym` identifiers are supposed to match the actual symbol whenever possible.
2020-07-15Rollup merge of #74344 - estebank:stringly-wobbly, r=eddybManish Goregaokar-7/+11
Remove string comparison and use diagnostic item instead r? @eddyb
2020-07-15Rollup merge of #74276 - lcnr:discriminant-kind-what, r=nagisaManish Goregaokar-15/+5
improve DiscriminantKind handling Adds a lang item `discriminant_type` for the associated type `DiscriminantKind::Discriminant`. Changes the discriminant of generators from `i32` to `u32`, which should not be observable to fix an oversight where MIR was using `u32` and codegen and typeck used `i32`.
2020-07-15const_eval_resolveBastian Kauschke-5/+5
2020-07-15ConstKind::UnevaluatedBastian Kauschke-7/+7
2020-07-15improve DiscriminantKind handlingBastian Kauschke-15/+5
This now reuses `fn discriminant_ty` in project, removing some code duplication. Doing so made me realize that we previously had a disagreement about the discriminant type of generators, with MIR using `u32` and codegen and trait selection using `i32`. We now always use `u32`.
2020-07-15Auto merge of #74175 - nnethercote:more-static-symbols, r=oli-obkbors-2/+6
More static symbols These commits add some more static symbols and convert lots of places to use them. r? @oli-obk
2020-07-14Remove string comparison and use diagnostic item insteadEsteban Küber-7/+11
2020-07-15Add and use more static symbols.Nicholas Nethercote-2/+6
Note that the output of `unpretty-debug.stdout` has changed. In that test the hash values are normalized from a symbol numbers to small numbers like "0#0" and "0#1". The increase in the number of static symbols must have caused the original numbers to contain more digits, resulting in different pretty-printing prior to normalization.
2020-07-14Reword messageEsteban Küber-1/+2
2020-07-14Remove redundant explanatory `note` for type parametersEsteban Küber-1/+6
2020-07-14Suggest borrowing in more unsized fn param casesEsteban Küber-35/+31
2020-07-14Suggest boxing or borrowing unsized fieldsEsteban Küber-18/+35
2020-07-14Suggest borrowing unsized argument typesEsteban Küber-3/+15
2020-07-10Avoid "whitelist"Tamir Duberstein-1/+1
Other terms are more inclusive and precise.
2020-07-09Rollup merge of #74070 - eddyb:forall-tcx-providers, r=nikomatsakisManish Goregaokar-3/+3
Use for<'tcx> fn pointers in Providers, instead of having Providers<'tcx>. In order to work around normalization-under-HRTB (for `provide!` in `rustc_metadata`), we ended up with this: ```rust struct Providers<'tcx> { type_of: fn(TyCtxt<'tcx>, DefId) -> Ty<'tcx>, // ... } ``` But what I initially wanted to do, IIRC, was this: ```rust struct Providers { type_of: for<'tcx> fn(TyCtxt<'tcx>, DefId) -> Ty<'tcx>, // ... } ``` This PR moves to the latter, for the simple reason that only the latter allows keeping a `Providers` value, or a subset of its `fn` pointer fields, around in a `static` or `thread_local!`, which can be really useful for custom drivers that override queries. (@jyn514 and I came across a concrete usecase of that in `rustdoc`) The `provide!` macro in `rustc_metadata` is fixed by making the query key/value types available as type aliases under `ty::query::query_{keys,values}`, not just associated types (this is the first commit). r? @nikomatsakis
2020-07-06Auto merge of #73978 - Mark-Simulacrum:shrink-paramenv, r=nnethercotebors-22/+27
Shrink ParamEnv to 16 bytes r? @nnethercote x.py check passes but I haven't tried running perf or tests
2020-07-05Use for<'tcx> fn pointers in Providers, instead of having Providers<'tcx>.Eduard-Mihai Burtescu-3/+3
2020-07-05Shrink ParamEnv to 16 bytesMark Rousskov-22/+27
2020-07-04instantiate_opaque_types LocalDefIdBastian Kauschke-11/+6
2020-07-02Auto merge of #73751 - eddyb:no-empty-tables, r=nikomatsakisbors-1/+1
Remove `TypeckTables::empty(None)` and make hir_owner non-optional. Each commit before the last one removes uses of `TypeckTables::empty(None)`, replacing the empty tables with having `Option` around the `&'tcx TypeckTables<'tcx>` that HIR visitors kept track of. The last commit removes the concept of "empty `TypeckTables`" altogether, guaranteeing that every `TypeckTables` corresponds to a HIR body owner. r? @nikomatsakis
2020-07-02Remove `TypeckTables::empty(None)` and make hir_owner non-optional.Eduard-Mihai Burtescu-1/+1
2020-07-01Rollup merge of #73306 - calebzulawski:target-feature-11-fn-trait-soundness, ↵Manish Goregaokar-1/+33
r=nikomatsakis Don't implement Fn* traits for #[target_feature] functions Closes #72012.
2020-06-30Make #[target_feature] Fn trait error message less confusingCaleb Zulawski-16/+15
2020-06-30change `skip_binder` to use T by valueBastian Kauschke-15/+15
2020-06-30stop taking references in RelateBastian Kauschke-4/+4
2020-06-27Don't implement Fn* for unsafe #[target_feature] functionsCaleb Zulawski-5/+3
2020-06-26Rollup merge of #73681 - jackh726:chalk-0.14, r=nikomatsakisManish Goregaokar-7/+8
Update Chalk to 0.14 Not a ton here. Notable changes: - Update to `0.14.0` - New dependency on `tracing`, in `librustc_traits` only - `FnAbi` from Chalk is `rustc_target::spec::abi::Abi` - `Dynamic` actually lowers region - Actually lower closures, with some tests. This doesn't 100% work, but can't confirm that's *only* because of closure lowering. - Use `FxIndexSet` instead of `FxHashSet` in `chalk_fulfill`, which seems to have fixed the non-deterministic test error ordering. Guess we'll see on CI - Actually implement `opaque_ty_data`, though I don't think this is sufficient for tests for them (I haven't added any) - Uncomment some of the chalk tests that now work r? @nikomatsakis
2020-06-24Implement associated lang itemsAaron Hill-8/+7
Fixes #70718 This commit allows making associated items (e.g. associated functions and types) into lang items via the `#[lang]` attribute. This allows such items to be accessed directly, rather than by iterating over the parent item's associated items. I've added `FnOnce::Output` as a lang item, and updated one old usage to use the new lang item. The remaining uses can be updated separately.
2020-06-24Update ChalkJack Huey-7/+8
2020-06-23Auto merge of #73643 - Manishearth:rollup-68dr8fz, r=Manishearthbors-60/+34
Rollup of 9 pull requests Successful merges: - #72271 (Improve compiler error message for wrong generic parameter order) - #72493 ( move leak-check to during coherence, candidate eval) - #73398 (A way forward for pointer equality in const eval) - #73472 (Clean up E0689 explanation) - #73496 (Account for multiple impl/dyn Trait in return type when suggesting `'_`) - #73515 (Add second message for LiveDrop errors) - #73567 (Clarify --extern documentation.) - #73572 (Fix typos in doc comments) - #73590 (bootstrap: no `config.toml` exists regression) Failed merges: r? @ghost
2020-06-23Rollup merge of #73578 - RalfJung:ty-ctxt-at, r=jonas-schievinkDylan DPC-1/+1
Make is_freeze and is_copy_modulo_regions take TyCtxtAt Make is_freeze and is_copy_modulo_regions take TyCtxtAt instead of separately taking TyCtxt and Span. This is consistent with is_sized.
2020-06-22remove leak-check from projectNiko Matsakis-2/+1
2020-06-22remove snapshot calls from "match" operations during selectNiko Matsakis-34/+14
Motivation: - we want to use leak-check sparingly, first off - these calls were essentially the same as doing the check during subtyping
2020-06-22upcasting traits requires only that things become more generalNiko Matsakis-15/+1
Revert the code that states that upcasting traits requires full equality and change to require that the source type is a subtype of the target type, as one would expect. As the comment states, this was an old bug that we didn't want to fix yet as it interacted poorly with the old leak-check. This fixes the old-lub-glb-object test, which was previously reporting too many errors (i.e., in the previous commit).
2020-06-22move leak-check to during coherence, candidate evalNiko Matsakis-11/+17
In particular, it no longer occurs during the subtyping check. This is important for enabling lazy normalization, because the subtyping check will be producing sub-obligations that could affect its results. Consider an example like for<'a> fn(<&'a as Mirror>::Item) = fn(&'b u8) where `<T as Mirror>::Item = T` for all `T`. We will wish to produce a new subobligation like <'!1 as Mirror>::Item = &'b u8 This will, after being solved, ultimately yield a constraint that `'!1 = 'b` which will fail. But with the leak-check being performed on subtyping, there is no opportunity to normalize `<'!1 as Mirror>::Item` (unless we invoke that normalization directly from within subtyping, and I would prefer that subtyping and unification are distinct operations rather than part of the trait solving stack). The reason to keep the leak check during coherence and trait evaluation is partly for backwards compatibility. The coherence change permits impls for `fn(T)` and `fn(&T)` to co-exist, and the trait evaluation change means that we can distinguish those two cases without ambiguity errors. It also avoids recreating #57639, where we were incorrectly choosing a where clause that would have failed the leak check over the impl which succeeds. The other reason to keep the leak check in those places is that I think it is actually close to the model we want. To the point, I think the trait solver ought to have the job of "breaking down" higher-ranked region obligation like ``!1: '2` into into region obligations that operate on things in the root universe, at which point they should be handed off to polonius. The leak check isn't *really* doing that -- these obligations are still handed to the region solver to process -- but if/when we do adopt that model, the decision to pass/fail would be happening in roughly this part of the code. This change had somewhat more side-effects than I anticipated. It seems like there are cases where the leak-check was not being enforced during method proving and trait selection. I haven't quite tracked this down but I think it ought to be documented, so that we know what precisely we are committing to. One surprising test was `issue-30786.rs`. The behavior there seems a bit "fishy" to me, but the problem is not related to the leak check change as far as I can tell, but more to do with the closure signature inference code and perhaps the associated type projection, which together seem to be conspiring to produce an unexpected signature. Nonetheless, it is an example of where changing the leak-check can have some unexpected consequences: we're now failing to resolve a method earlier than we were, which suggests we might change some method resolutions that would have been ambiguous to be successful. TODO: * figure out remainig test failures * add new coherence tests for the patterns we ARE disallowing
2020-06-22rewrite leak check to be based on universesNiko Matsakis-14/+17
In the new leak check, instead of getting a list of placeholders to track, we look for any placeholder that is part of a universe which was created during the snapshot. We are looking for the following error patterns: * P1: P2, where P1 != P2 * P1: R, where R is in some universe that cannot name P1 This new leak check is more precise than before, in that it accepts this patterns: * R: P1, even if R cannot name P1, because R = 'static is a valid sol'n * R: P1, R: P2, as above Note that this leak check, when running during subtyping, is less efficient than before in some sense because it is going to check and re-check all the universes created since the snapshot. We're going to move when the leak check runs to try and correct that.
2020-06-21Auto merge of #73180 - matthewjasper:predicate-cache, r=nikomatsakisbors-1/+1
Cache flags and escaping vars for predicates With predicates becoming interned (rust-lang/compiler-team#285) this is now possible and could be a perf win. It would become an even larger win once we have recursive predicates. cc @lcnr @nikomatsakis r? @ghost
2020-06-21Auto merge of #72936 - jackh726:chalk-more, r=nikomatsakisbors-1/+5
Upgrade Chalk Things done in this PR: - Upgrade Chalk to `0.11.0` - Added compare-mode=chalk - Bump rustc-hash in `librustc_data_structures` to `1.1.0` to match Chalk - Removed `RustDefId` since the builtin type support is there - Add a few more `FIXME(chalk)`s for problem spots I hit when running all tests with chalk - Added some more implementation code for some newer builtin Chalk types (e.g. `FnDef`, `Array`) - Lower `RegionOutlives` and `ObjectSafe` predicates - Lower `Dyn` without the region - Handle `Int`/`Float` `CanonicalVarKind`s - Uncomment some Chalk tests that actually work now - Remove the revisions in `src/test/ui/coherence/coherence-subtyping.rs` since they aren't doing anything different r? @nikomatsakis
2020-06-21Make is_freeze and is_copy_modulo_regions take TyCtxtAtRalf Jung-1/+1
2020-06-21Replace `is_global` call on data with call on predicateMatthew Jasper-1/+1
2020-06-20Auto merge of #73563 - Manishearth:rollup-oowgwwm, r=Manishearthbors-37/+332
Rollup of 9 pull requests Successful merges: - #72456 (Try to suggest dereferences on trait selection failed) - #72788 (Projection bound validation) - #72790 (core/time: Add Duration methods for zero) - #73227 (Allow multiple `asm!` options groups and report an error on duplicate options) - #73287 (lint: normalize projections using opaque types) - #73291 (Pre-compute `LocalDefId` <-> `HirId` mappings and remove `NodeId` <-> `HirId` conversion APIs) - #73378 (Remove use of specialization from librustc_arena) - #73411 (Update bootstrap to rustc 1.45.0-beta.2 (1dc0f6d8e 2020-06-15)) - #73443 (ci: allow gating GHA on everything but macOS) Failed merges: r? @ghost
2020-06-20Rollup merge of #72788 - matthewjasper:projection-bound-validation, ↵Manish Goregaokar-36/+35
r=nikomatsakis Projection bound validation During selection we use bounds declared on associated types (e.g. `type X: Copy`) to satisfy trait/projection bounds. This would be fine so long as those bounds are checked on any impls/trait objects. For simple cases they are because the bound `Self::X: Copy` gets normalized when we check the impl. However, for default values with specialization and higher-ranked bounds from GATs or otherwise, we can't normalize when checking the impl, and so we use the bound from the trait to prove that the bound applies to the impl, which is clearly unsound. This PR makes 2 fixes for this: 1. Requiring that the bounds on the trait apply to a projection type with the corresponding substs, so a bound `for<'a> <Self as X<'a>>::U: Copy` on the trait cannot be used to prove `<T as X<'_>>::U: Copy`. 2. Actually checking that the bounds that we still allow apply to generic/default associated types. Opening for a crater run. Closes #68641 Closes #68642 Closes #68643 Closes #68644 Closes #68645 Closes #68656 r? @ghost
2020-06-20Rollup merge of #72456 - ldm0:dereftrait, r=estebankManish Goregaokar-1/+297
Try to suggest dereferences on trait selection failed Fixes #39029 Fixes #62530 This PR consists of two parts: 1. Decouple `Autoderef` with `FnCtxt` and move `Autoderef` to `librustc_trait_selection`. 2. Try to suggest dereferences when trait selection failed. The first is needed because: 1. For suggesting dereferences, the struct `Autoderef` should be used. But before this PR, it is placed in `librustc_typeck`, which depends on `librustc_trait_selection`. But trait selection error emitting happens in `librustc_trait_selection`, if we want to use `Autoderef` in it, dependency loop is inevitable. So I moved the `Autoderef` to `librustc_trait_selection`. 2. Before this PR, `FnCtxt` is coupled to `Autoderef`, and `FnCtxt` only exists in `librustc_typeck`. So decoupling is needed. After this PR, we can get suggestion like this: ``` error[E0277]: the trait bound `&Baz: Happy` is not satisfied --> $DIR/trait-suggest-deferences-multiple.rs:34:9 | LL | fn foo<T>(_: T) where T: Happy {} | ----- required by this bound in `foo` ... LL | foo(&baz); | ^^^^ | | | the trait `Happy` is not implemented for `&Baz` | help: consider adding dereference here: `&***baz` error: aborting due to previous error For more information about this error, try `rustc --explain E0277`. ``` r? @estebank
2020-06-20Prevent incorrect help message for dereference suggestionDonough Liu-1/+1
generated by cgit-pink 1.4.1-3-g733a5 (git 2.37.1) at 2026-07-04 06:02:00 +0000