Save/load incremental compilation dep graph
Contains the code to serialize/deserialize the dep graph to disk between executions. We also hash the item contents and compare to the new hashes. Also includes a unit test harness. There are definitely some known limitations, such as https://github.com/rust-lang/rust/issues/32014 and https://github.com/rust-lang/rust/issues/32015, but I am leaving those for follow-up work.
Note that this PR builds on https://github.com/rust-lang/rust/pull/32007, so the overlapping commits can be excluded from review.
r? @michaelwoerister
Lay groundwork for RFC 1422 and improve `PrivateItemsInPublicInterfacesVisitor`
This PR lays groundwork for RFC 1422 (cc #32409) and improves `PrivateItemsInPublicInterfacesVisitor`. More specifically, it
- Refactors away `hir::Visibility::inherit_from`, the semantics of which are obsolete.
- Makes `hir::Visibility` non-`Copy` so that we will be able to add new variants to represent `pub(restricted)` (for example, `Visibility::Restricted(Path)`).
- Adds a new `Copy` type `ty::Visibility` that represents a visibility value, i.e. a characterization of where an item is accessible. This is able to represent `pub(restricted)` visibilities.
- Improves `PrivateItemsInPublicInterfacesVisitor` so that it checks for items in an interface that are less visible than the interface. This fixes#30079 but doesn't change any other behavior.
r? @nikomatsakis
Suggest adding a where-clause when that can help
Suggest adding a where-clause when there is an unmet trait-bound that can be satisfied if some type can implement it.
r? @nikomatsakis
Fix LLVM assert when handling bad intrinsic monomorphizations
Passing an invalid type to certain intrinsics would trigger an LLVM assert even though the invalid type was caught by the compiler.
r? @eddyb
You can now pass `-Z incremental=dir` as well as saying `-Z
query-dep-graph` if you want to enable queries for some other
purpose. Accessor functions take the place of computed boolean flags.
Fix "consider removing this semicolon" help
Check last statement in a block, not the first.
Example of current weirdness: http://is.gd/w80J9h
The help was only rarely emitted, and if so, often incorrectly (see above playpen). It was basically only useful with single-statement functions.
Fix issue: Global paths in `use` directives can begin with `super` or `self` #32225
This PR fixes#32225 by warning on `use ::super::...` and `use ::self::...` on `resolve`.
Current changes is the most minimal and ad-hoc.
resolve: Improve import failure detection and lay groundwork for RFC 1422
This PR improves import failure detection and lays some groundwork for RFC 1422.
More specifically, it
- Avoids recomputing the resolution of an import directive's module path.
- Refactors code in `resolve_imports` that does not scale to the arbitrarily many levels of visibility that will be required by RFC 1422.
- Replaces `ModuleS`'s fields `public_glob_count`, `private_glob_count`, and `resolved_globs` with a list of glob import directives `globs`.
- Replaces `NameResolution`'s fields `pub_outstanding_references` and `outstanding_references` with a field `single_imports` of a newly defined type `SingleImports`.
- Improves import failure detection by detecting cycles that include single imports (currently, only cycles of globs are detected). This fixes#32119.
r? @nikomatsakis
Only allow using the atomic intrinsics on integer types
Using these with non-integer types results in LLVM asserts. Atomic operations on non-integer types will require values be transmuted into an integer type of suitable size.
This doesn't affect the standard library since `AtomicBool` and `AtomicPtr` currently use `usize` for atomic operations.
r? @eddyb
When deciding on a coinductive match, we were examining the new
obligation and the backtrace, but not the *current* obligation that goes
in between the two. Refactoring the code to just have the cycle given
as input also made things a lot simpler.
Integrate privacy into field and method selection
This PR integrates privacy checking into field and method selection so that an inaccessible field/method can not stop an accessible field/method from being used (fixes#12808 and fixes#22684).
r? @eddyb
diagnostics: make paths to external items more visible
This PR changes the reported path for an external item so that it is visible from at least one local module (i.e. it does not use any inaccessible external modules) if possible. If the external item's crate was declared with an `extern crate`, the path is guarenteed to use the `extern crate`.
Fixes#23224, fixes#23355, fixes#26635, fixes#27165.
r? @nrc
Gate parser recovery via debugflag
Gate parser recovery via debugflag
Put in `-Z continue_parse_after_error`
This works by adding a method, `fn abort_if_no_parse_recovery`, to the
diagnostic handler in `syntax::errors`, and calling it after each
error is emitted in the parser.
(We might consider adding a debugflag to do such aborts in other
places where we are currently attempting recovery, such as resolve,
but I think the parser is the really important case to handle in the
face of #31994 and the parser bugs of varying degrees that were
injected by parse error recovery.)
r? @nikomatsakis
parser recovery (so that expected errors match up)
I'm opting into parser recovery in all these cases out of expediency,
not because the error messages you get with recovery enabled are
actually all that usable in all cases listed.
Prevent bumping the parser past the EOF.
Makes `Parser::bump` after EOF into an ICE, forcing callers to avoid repeated EOF bumps.
This ICE is intended to break infinite loops where EOF wasn't stopping the loop.
For example, the handling of EOF in `parse_trait_items`' recovery loop fixes#32446.
But even without this specific fix, the ICE is triggered, which helps diagnosis and UX.
This is a `[breaking-change]` for plugins authors who eagerly eat multiple EOFs.
See https://github.com/docopt/docopt.rs/pull/171 for such an example and the necessary fix.
melt the ICE when lowering an impossible range
Emit a fatal error instead of panicking when HIR lowering encounters a range with no `end` point.
This involved adding a method to wire up `LoweringContext::span_fatal`.
Fixes#32245 (cc @nodakai).
r? @nrc
