Map invalid Spans to DUMMY_SP during crate metadata encoding.
This mirrors what we do for stabilizing the incr. comp. cache and is necessary for reproducible builds. For the incr. comp. cache, we *have* to do this because the encoding there cannot represent broken Spans. Metadata encoding has to be in sync with that as not to get unexpected interactions when compiling incrementally.
This should help with fixing issue https://github.com/rust-lang/rust/issues/47066.
r? @alexcrichton
Bump to 1.25.0
* Bump the release version to 1.25
* Bump the bootstrap compiler to the recent beta
* Allow using unstable rustdoc features on beta - this fix has been applied to
the beta branch but needed to go to the master branch as well.
Update `rand` crate to `0.3.19`.
Update `log` crate to `0.3.9` and `0.4.1`.
Update `parking_lot_core` crate to `0.2.9`.
Upgrade all flate2 dependencies to `1.0.1`.
- Update `rust-installer` submodule.
incr.comp.: Use an array instead of a hashmap for storing result hashes.
Doing so should result in some of the core tracking components being faster.
r? @nikomatsakis
Followup for #46112.
Sorting by crate-num should ensure that we favor `std::foo::bar` over
`any_other_crate::foo::bar`.
Interestingly, *this* change had a much larger impact on our internal
test suite than PR #46708 (which was my original fix to #46112).
The Generics now contain one Vec of an enum for the generic parameters,
rather than two separate Vec's for lifetime and type parameters.
Additionally, places that previously used Vec<LifetimeDef> now use
Vec<GenericParam> instead.
Sorting by crate-num should ensure that we favor `std::foo::bar` over
`any_other_crate::foo::bar`.
Interestingly, *this* change had a much larger impact on our internal
test suite than PR #46708 (which was my original fix to #46112).
trait alias infrastructure
This will be an implementation of trait aliases (RFC 1733, #41517).
Progress so far:
- [x] Feature gate
- [x] Add to parser
- [x] `where` clauses
- [x] prohibit LHS type parameter bounds via AST validation https://github.com/rust-lang/rust/pull/45047#discussion_r143575575
- [x] Add to AST and HIR
- [x] make a separate PathSource for trait alias contexts https://github.com/rust-lang/rust/pull/45047#discussion_r143353932
- [x] Stub out enough of typeck and resolve to just barely not ICE
Postponed:
- [ ] Actually implement the alias part
- [ ] #21903
- [ ] #24010
I need some pointers on where to start with that last one. The test currently does this:
```
error[E0283]: type annotations required: cannot resolve `_: CD`
--> src/test/run-pass/trait-alias.rs:34:16
|
34 | let both = foo();
| ^^^
|
= note: required by `foo`
```
Fix visible_parent_map to choose globally minimal paths
Fix#46112: visible_parent_map construction needs a BFS over whole crate forest to get globally minimal paths.
(There are other latent bugs that were e.g. causing this test case to have weirdness like `<unnamed>` in the diagnostic output. Those bugs are not fixed here, since they are issues long-standing in the stable channel.)
Record all imports (`use`, `extern crate`) in the crate metadata
This PR adds non-`pub` `use` and `extern crate` imports in the crate metadata since hygienic macros invoked in other crates may use them. We already include all other non-`pub` items in the crate metadata. This improves import suggestions in some cases.
Fixes#42337.
r? @nrc
incr.comp.: Remove ability to produce incr. comp. hashes during metadata export.
This functionality has been superseded by on-import hashing, which can be less conservative and does not require extra infrastructure.
r? @nikomatsakis
move closure kind, signature into `ClosureSubsts`
Instead of using side-tables, store the closure-kind and signature in the substitutions themselves. This has two key effects:
- It means that the closure's type changes as inference finds out more things, which is very nice.
- As a result, it avoids the need for the `freshen_closure_like` code (though we still use it for generators).
- It avoids cyclic closures calls.
- These were never meant to be supported, precisely because they make a lot of the fancy inference that we do much more complicated. However, due to an oversight, it was previously possible -- if challenging -- to create a setup where a closure *directly* called itself (see e.g. #21410).
We have to see what the effect of this change is, though. Needs a crater run. Marking as [WIP] until that has been assessed.
r? @arielb1
impl Trait Lifetime Handling
This PR implements the updated strategy for handling `impl Trait` lifetimes, as described in [RFC 1951](https://github.com/rust-lang/rfcs/blob/master/text/1951-expand-impl-trait.md) (cc #42183).
With this PR, the `impl Trait` desugaring works as follows:
```rust
fn foo<T, 'a, 'b, 'c>(...) -> impl Foo<'a, 'b> { ... }
// desugars to
exists type MyFoo<ParentT, 'parent_a, 'parent_b, 'parent_c, 'a, 'b>: Foo<'a, 'b>;
fn foo<T, 'a, 'b, 'c>(...) -> MyFoo<T, 'static, 'static, 'static, 'a, 'b> { ... }
```
All of the in-scope (parent) generics are listed as parent generics of the anonymous type, with parent regions being replaced by `'static`. Parent regions referenced in the `impl Trait` return type are duplicated into the anonymous type's generics and mapped appropriately.
One case came up that wasn't specified in the RFC: it's possible to write a return type that contains multiple regions, neither of which outlives the other. In that case, it's not clear what the required lifetime of the output type should be, so we generate an error.
There's one remaining FIXME in one of the tests: `-> impl Foo<'a, 'b> + 'c` should be able to outlive both `'a` and `'b`, but not `'c`. Currently, it can't outlive any of them. @nikomatsakis and I have discussed this, and there are some complex interactions here if we ever allow `impl<'a, 'b> SomeTrait for AnonType<'a, 'b> { ... }`, so the plan is to hold off on this until we've got a better idea of what the interactions are here.
cc #34511.
Fixes#44727.
After this change, impl Trait existentials are
desugared to a new `abstract type` definition
paired with a set of lifetimes to apply.
In-scope generics are included as parents of the
`abstract type` generics. Parent regions are
replaced with static, and parent regions
referenced in the `impl Trait` type are duplicated
at the end of the `abstract type`'s generics.
incr.comp.: Implement query result cache and use it to cache type checking tables.
This is a spike implementation of caching more than LLVM IR and object files when doing incremental compilation. At the moment, only the `typeck_tables_of` query is cached but MIR and borrow-check will follow shortly. The feature is activated by running with `-Zincremental-queries` in addition to `-Zincremental`, it is not yet active by default.
r? @nikomatsakis
Replace hir::TyImplTrait with TyImplTraitUniversal and
TyImplTraitExistential.
Add an ImplTraitContext enum to rustc::hir::lowering to track the kind
and allowedness of an impl Trait.
Significantly alter lowering to thread ImplTraitContext and one other
boolean parameter described below throughought much of lowering.
The other parameter is for tracking if lowering a function is in a trait
impl, as there is not enough information to otherwise know this
information during lowering otherwise.
This change also removes the checks from ast_ty_to_ty for impl trait
allowedness as they are now all taking place in HIR lowering.
