The AST part of https://github.com/rust-lang/rust/pull/31937
Unlike HIR, AST still uses `Option` for field names because parser can't know field indexes reliably due to constructions like
```
struct S(#[cfg(false)] u8, u8); // The index of the second field changes from 1 during parsing to 0 after expansion.
```
and I wouldn't like to put the burden of renaming fields on expansion passes and syntax extensions.
plugin-[breaking-change] cc https://github.com/rust-lang/rust/issues/31645
r? @Manishearth
[breaking-batch] Add support for `pub(restricted)` syntax in the AST
This PR allows the AST to represent the `pub(restricted)` syntax from RFC 1422 (cc #32409).
More specifically, it makes `ast::Visibility` non-`Copy` and adds two new variants, `Visibility::Crate` for `pub(crate)` and `Visitibility::Restricted { path: P<Path>, id: NodeId }` for `pub(path)`.
plugin-[breaking-change] cc #31645
r? @pnkfelix
1. In the English/Japanese phrases example in the "Multiple File
Crates" section of the "Crates and Modules" chapter, there are a total
of 8 module files that Rust looks for, while only four were
listed. This commit lists all 8 explicitly.
2. Title case fix.
The initial implementation of specialization did not use the
`fast_reject` mechanism when checking for overlap, which caused a
serious performance regression in some cases.
This commit modifies the specialization graph to use simplified types
for fast rejection when possible, and along the way refactors the logic
for building the specialization graph.
Closes#32499
trans: don't declare symbols that were already imported.
Fixes#32740 by checking for a declaration before attempting a new one.
Before, `LLVMGetOrInsertFunction` was called for a existing import, but with a different type.
The returned value was a cast function pointer instead of a declaration, and we gave this
value to `llvm::SetFunctionCallConv` & friends , which triggered an LLVM assertion.
Where T is a type that can be compared for equality bytewise, we can use
memcmp. We can also use memcmp for PartialOrd, Ord for [u8] and by
extension &str.
This is an improvement for example for the comparison [u8] == [u8] that
used to emit a loop that compared the slices byte by byte.
One worry here could be that this introduces function calls to memcmp
in contexts where it should really inline the comparison or even
optimize it out, but llvm takes care of recognizing memcmp specifically.
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.
rustdoc: make rustdoc less pass-aware
Instead of hardcoding knowledge about the strip-private pass into the
rendering process we represent (some) stripped items as `ItemEnum::StrippedItem`.
Rustdoc will, for example, generate redirect pages for public items
contained in private modules which have been re-exported to somewhere
externally reachable - this will now not only work for the `strip-private`
pass, but for other passes as well, such as the `strip-hidden` pass.
r? @alexcrichton
Plumb obligations through librustc/infer
Like #32542, but more like #31867.
TODO before merge: make an issue for the propagation of obligations through... uh, everywhere... then replace the `#????`s with the actual issue number.
cc @jroesch
r? @nikomatsakis
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.
Remove implicit binder from `FnSpace` in `VecPerParamSpace` (fixes#20526)
This removes the implicit binder from `FnSpace` in `VecPerParamSpace` so that `Binder<T>` is the only region binder (as described in issue #20526), and refactors away `enter_region_binder` and `exit_region_binder` from `TypeFolder`.
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
