The value in `MacArgs::Eq` is currently represented as a `Token`.
Because of `TokenKind::Interpolated`, `Token` can be either a token or
an arbitrary AST fragment. In practice, a `MacArgs::Eq` starts out as a
literal or macro call AST fragment, and then is later lowered to a
literal token. But this is very non-obvious. `Token` is a much more
general type than what is needed.
This commit restricts things, by introducing a new type `MacArgsEqKind`
that is either an AST expression (pre-lowering) or an AST literal
(post-lowering). The downside is that the code is a bit more verbose in
a few places. The benefit is that makes it much clearer what the
possibilities are (though also shorter in some other places). Also, it
removes one use of `TokenKind::Interpolated`, taking us a step closer to
removing that variant, which will let us make `Token` impl `Copy` and
remove many "handle Interpolated" code paths in the parser.
Things to note:
- Error messages have improved. Messages like this:
```
unexpected token: `"bug" + "found"`
```
now say "unexpected expression", which makes more sense. Although
arbitrary expressions can exist within tokens thanks to
`TokenKind::Interpolated`, that's not obvious to anyone who doesn't
know compiler internals.
- In `parse_mac_args_common`, we no longer need to collect tokens for
the value expression.
std: directly use pthread in UNIX parker implementation
`Mutex` and `Condvar` are being replaced by more efficient implementations, which need thread parking themselves (see #93740). Therefore we should use the `pthread` synchronization primitives directly. Also, we can avoid allocating the mutex and condition variable because the `Parker` struct is being placed in an `Arc` anyways.
This basically is just a copy of the current `Mutex` and `Condvar` code, which will however be removed (again, see #93740). An alternative implementation could be to use dedicated private `OsMutex` and `OsCondvar` types, but all the other platforms supported by std actually have their own thread parking primitives.
I used `Pin` to guarantee a stable address for the `Parker` struct, while the current implementation does not, rather using extra unsafe declaration. Since the thread struct is shared anyways, I assumed this would not add too much clutter while being clearer.
Rollup of 5 pull requests
Successful merges:
- #95312 (Ensure that `'_` and GAT yields errors)
- #96405 (Migrate ambiguous plus diagnostic to the new derive macro)
- #96409 (Recover suggestions to introduce named lifetime under NLL)
- #96433 (rustc_ast: Harmonize delimiter naming with `proc_macro::Delimiter`)
- #96480 (Fixed grammatical error in example comment)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
rustc_ast: Harmonize delimiter naming with `proc_macro::Delimiter`
Compiler cannot reuse `proc_macro::Delimiter` directly due to extra impls, but can at least use the same naming.
After this PR the only difference between these two enums is that `proc_macro::Delimiter::None` is turned into `token::Delimiter::Invisible`.
It's my mistake that the invisible delimiter is called `None` on stable, during the stabilization I audited the naming and wrote the docs, but missed the fact that the `None` naming gives a wrong and confusing impression about what this thing is.
cc https://github.com/rust-lang/rust/pull/96421
r? ``@nnethercote``
Make sure `-Dunused-crate-dependencies --json unused-externs` makes rustc exit with error status
This PR:
- fixes compiletest to understand unused extern notifications
- adds tests for `--json unused-externs`
- makes sure that deny-level unused externs notifications are treated as compile errors
- refactors the `emit_unused_externs` callstack to plumb through the level as an enum as a string, and adds `Level::is_error`
Update: adds `--json unused-externs-silent` with the original behaviour since Cargo needs it. Should address `@est31's` concerns.
Fixes: https://github.com/rust-lang/rust/issues/96068
Less `NoDelim`
Currently there are several places where `NoDelim` (which really means "implicit delimiter" or "invisible delimiter") is used to mean "no delimiter". The name `NoDelim` is a bit misleading, and may be a cause.
This PR changes these places, e.g. by changing a `DelimToken` to `Option<DelimToken>` and then using `None` to mean "no delimiter". As a result, the *only* place where `NoDelim` values are now produced is within:
- `Delimiter::to_internal()`, when converting from `Delimiter::None`.
- `FlattenNonterminals::process_token()`, when converting `TokenKind::Interpolated`.
r? ````@petrochenkov````
Perform lifetime resolution on the AST for lowering
Lifetime resolution is currently implemented several times. Once during lowering in order to introduce in-band lifetimes, and once in the resolve_lifetimes query. However, due to the global nature of lifetime resolution and how it interferes with hygiene, it is better suited on the AST.
This PR implements a first draft of lifetime resolution on the AST. For now, we specifically target named lifetimes and everything we need to remove lifetime resolution from lowering. Some diagnostics have already been ported, and sometimes made more precise using available hygiene information. Follow-up PRs will address in particular the resolution of anonymous lifetimes on the AST.
We reuse the rib design of the current resolution framework. Specific `LifetimeRib` and `LifetimeRibKind` types are introduced. The most important variant is `LifetimeRibKind::Generics`, which happens each time we encounter something which may introduce generic lifetime parameters. It can be an item or a `for<...>` binder. The `LifetimeBinderKind` specifies how this rib behaves with respect to in-band lifetimes.
r? `@petrochenkov`
Since Cargo wants to do its own fatal error handling for unused
dependencies, add the option `--json unused-externs-silent` which
has the original behaviour of not indicating non-zero exit status for
`deny`/`forbid`-level unused dependencies.
There were none at all. These test for original functionality,
but this also adds a test that `-Dunused-crate-dependencies`
causes a compilation failure, which currently fails
(https://github.com/rust-lang/rust/issues/96068). This is fixed in
subsequent changes.
Move `download-ci-llvm` out of bootstrap.py
This is ready for review. It has been tested on Windows, Linux, and NixOS.
The second commit ports the changes from https://github.com/rust-lang/rust/pull/95234 to Rust; I can remove it if desired.
Helps with https://github.com/rust-lang/rust/issues/94829.
As a follow-up, this makes it possible to avoid downloading llvm until it's needed for building `rustc_llvm`; it would be nice to do that, but it shouldn't go in the first draft. It might also be possible to avoid requiring python until tests run (currently there's a check in `sanity.rs`), but I haven't looked too much into that.
`@rustbot` label +A-rustbuild
Define a dedicated error type for `HandleOrNull` and `HandleOrInvalid`.
Define `NullHandleError` and `InvalidHandleError` types, that implement std::error::Error, and use them as the error types in `HandleOrNull` and `HandleOrInvalid`,
This addresses [this concern](https://github.com/rust-lang/rust/issues/87074#issuecomment-1080031167).
This is the same as #95387.
r? `@joshtriplett`
Rollup of 6 pull requests
Successful merges:
- #92569 (Improve Error Messaging for Unconstructed Structs and Enum Variants in Generic Contexts)
- #96370 (Cleanup `report_method_error` a bit)
- #96383 (Fix erased region escaping into wfcheck due to #95395)
- #96385 (Recover most `impl Trait` and `dyn Trait` lifetime bound suggestions under NLL)
- #96410 (rustdoc: do not write `{{root}}` in `pub use ::foo` docs)
- #96430 (Fix handling of `!` in rustdoc search)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Recover most `impl Trait` and `dyn Trait` lifetime bound suggestions under NLL
This is done by replacing the duplicated (and very partial) implementation from borrowck with one inspsired from `NiceRegionError::try_report_static_impl_trait` and by re-using `suggest_new_region_bound`.
Fixes#96277
r? ```@jackh726```
Fix erased region escaping into wfcheck due to #95395
We can just use `liberate_late_bound_regions` instead of `erase_late_bound_regions`... This gives us `ReEarlyBound` instead of `ReErased`, the former being something typeck actually knows how to deal with...
Fixes#96381
Side-note: We only actually get far enough in the compiler pipeline to cause this ICE when we're invoking rustdoc. We actually abort rustc right before wfcheck because of the error that we emit (having `_` in the type signature). Why does rustdoc keep going even though we raise an error?
Fix incremental perf regression unsafety checking
Perf regression introduced in #96294
We will simply avoid emitting the name of the unsafe function in MIR unsafeck, since we're moving to THIR unsafeck anyway.
Suggest calling method on nested field when struct is missing method
Similar to the suggestion to change `x.field` to `x.nested.field`, implement a similar suggestion for when `x.method()` should be replaced with `x.nested.method()`.
