ignore higher-ranked object bound conditions created by WF
In the `issue-53548` test added in this PR, the `Box<dyn Trait>` type is expanded to `Box<dyn Trait + 'static>`, but the generator "witness" that results is `for<'r> { Box<dyn Trait + 'r> }`. The WF code was encountering an ICE (when debug-assertions were enabled) and an unexpected compilation error (without debug-asserions) when trying to process this `'r` region bound. In particular, to be WF, the region bound must meet the requirements of the trait, and hence we got `for<'r> { 'r: 'static }`. This would ICE because the `Binder` constructor we were using was assering that no higher-ranked regions were involved (because the WF code is supposed to skip those). The error (if debug-asserions were disabled) came because we obviously cannot prove that `'r: 'static` for any region `'r`. Pursuant with
our "lazy WF" strategy for higher-ranked regions, the fix is not to require that `for<'r> { 'r: 'static }` holds (this is also analogous to what we would do for higher-ranked regions appearing within the trait in other positions).
Fixes#53548
r? @pnkfelix
Fix#54822 and associated faulty tests
Type checking associated constants can require trait bounds, but an empty
parameter environment was provided to the trait solver. Providing an
appropriate parameter environment seems to fix#54822 and also make one of the
cases in src/test/ui/nll/trait-associated-constant.rs that should compile
successfully do so. It also (slightly) improves the error message in
src/test/ui/associated-const/associated-const-generic-obligations.rs
In the `issue-53548` test added in this commit, the `Box<dyn Trait>`
type is expanded to `Box<dyn Trait + 'static>`, but the generator
"witness" that results is `for<'r> { Box<dyn Trait + 'r> }`. The WF
code was encountering an ICE (when debug-assertions were enabled) and
an unexpected compilation error (without debug-asserions) when trying
to process this `'r` region bound. In particular, to be WF, the region
bound must meet the requirements of the trait, and hence we got
`for<'r> { 'r: 'static }`. This would ICE because the `Binder`
constructor we were using was assering that no higher-ranked regions
were involved (because the WF code is supposed to skip those). The
error (if debug-asserions were disabled) came because we obviously
cannot prove that `'r: 'static` for any region `'r`. Pursuant with
our "lazy WF" strategy for higher-ranked regions, the fix is not to
require that `for<'r> { 'r: 'static }` holds (this is also analogous
to what we would do for higher-ranked regions appearing within the
trait in other positions).
Warning period for detecting nested impl trait
Here is some proposed code for making a warning period for the new checking of nested impl trait.
It undoes some of the corrective effects of PR #57730, by using boolean flags to track parts of the analysis that were previously skipped prior to PRs #57730 and #57981 landing.
Cc #57979
Make migrate mode work at item level granularity
Migrate mode now works entirely at the item level rather than the body level,
ensuring that we don't lose any errors in contained closures.
Closes#58776
r? @pnkfelix
Type checking associated constants can require trait bounds, but an empty
parameter environment was provided to the trait solver. Providing an
appropriate parameter environment seems to fix#54822 and also make one of the
cases in src/test/ui/nll/trait-associated-constant.rs that should compile
successfully do so. It also (slightly) improves the error message in
src/test/ui/associated-const/associated-const-generic-obligations.rs
Refactor passes and pass execution to be more parallel
For `syntex_syntax` (with 16 threads and 8 cores):
- Cuts `misc checking 1` from `0.096s` to `0.08325s`.
- Cuts `misc checking 2` from `0.3575s` to `0.2545s`.
- Cuts `misc checking 3` from `0.34625s` to `0.21375s`.
- Cuts `wf checking` from `0.3085s` to `0.05025s`.
Reduces overall execution time for `syntex_syntax` (with 8 threads and cores) from `4.92s` to `4.34s`.
Subsumes https://github.com/rust-lang/rust/pull/58494
Blocked on https://github.com/rust-lang/rust/pull/58250
r? @michaelwoerister
rust-lldb: fix crash when printing empty string
Fixes#52185.
~Re-enables the pretty-std debuginfo test and tweaks the test as necessary to get it to pass again. This reveals that lldb's formatting of enums is broken (#58492). I also removed the emoji from the test because I couldn't get the docker image's gdb to print the emoji, just octal escapes (https://github.com/rust-lang/rust/pull/53154/files#r208263904).~
rustdoc: add option to calculate "documentation coverage"
This PR adds a new flag to rustdoc, `--show-coverage`. When passed, this flag will make rustdoc count the number of items in a crate with documentation instead of generating docs. This count will be output as a table of each file in the crate, like this (when run on my crate `egg-mode`):
```
+-------------------------------------+------------+------------+------------+
| File | Documented | Total | Percentage |
+-------------------------------------+------------+------------+------------+
| src/auth.rs | 16 | 16 | 100.0% |
| src/common/mod.rs | 1 | 1 | 100.0% |
| src/common/response.rs | 9 | 9 | 100.0% |
| src/cursor.rs | 24 | 24 | 100.0% |
| src/direct/fun.rs | 6 | 6 | 100.0% |
| src/direct/mod.rs | 41 | 41 | 100.0% |
| src/entities.rs | 50 | 50 | 100.0% |
| src/error.rs | 27 | 27 | 100.0% |
| src/lib.rs | 1 | 1 | 100.0% |
| src/list/fun.rs | 19 | 19 | 100.0% |
| src/list/mod.rs | 22 | 22 | 100.0% |
| src/media/mod.rs | 27 | 27 | 100.0% |
| src/place/fun.rs | 8 | 8 | 100.0% |
| src/place/mod.rs | 35 | 35 | 100.0% |
| src/search.rs | 26 | 26 | 100.0% |
| src/service.rs | 74 | 74 | 100.0% |
| src/stream/mod.rs | 49 | 49 | 100.0% |
| src/tweet/fun.rs | 15 | 15 | 100.0% |
| src/tweet/mod.rs | 73 | 73 | 100.0% |
| src/user/fun.rs | 24 | 24 | 100.0% |
| src/user/mod.rs | 87 | 87 | 100.0% |
+-------------------------------------+------------+------------+------------+
| Total | 634 | 634 | 100.0% |
+-------------------------------------+------------+------------+------------+
```
Trait implementations are not counted because by default they "inherit" the docs from the trait, even though an impl can override those docs. Similarly, inherent impl blocks are not counted at all, because for the majority of cases such docs are not useful. (The usual pattern for inherent impl blocks is to throw all the methods on a type into a single impl block. Any docs you would put on that block would be better served on the type itself.)
In addition, `--show-coverage` can be combined with `--document-private-items` to get the coverage counts for everything in the crate, not just public items.
The coverage calculation is implemented as a late pass and two new sets of passes which strip out most of the work that rustdoc otherwise does when generating docs. The is because after the new pass is executed, rustdoc immediately closes instead of going on to generate documentation.
Many examples of coverage calculations have been included as `rustdoc-ui` tests.
r? @rust-lang/rustdoc
overhaul unused doc comments lint
This PR contains a number of improvements to the `unused_doc_comments` lint.
- Extends the span to cover the entire comment when using sugared doc comments.
- Triggers the lint for all unused doc comments on a node, instead of just the first one.
- Triggers the lint on macro expansions, and provides a help note explaining that doc comments must be expanded by the macro.
- Adds a label pointing at the node that cannot be documented.
Furthermore, this PR fixes any instances in rustc where a macro expansion was erroneously documented.
Rollup of 24 pull requests
Successful merges:
- #58080 (Add FreeBSD armv6 and armv7 targets)
- #58204 (On return type `impl Trait` for block with no expr point at last semi)
- #58269 (Add librustc and libsyntax to rust-src distribution.)
- #58369 (Make the Entry API of HashMap<K, V> Sync and Send)
- #58861 (Expand where negative supertrait specific error is shown)
- #58877 (Suggest removal of `&` when borrowing macro and appropriate)
- #58883 (Suggest appropriate code for unused field when destructuring pattern)
- #58891 (Remove stray ` in the docs for the FromIterator implementation for Option)
- #58893 (race condition in thread local storage example)
- #58906 (Monomorphize generator field types for debuginfo)
- #58911 (Regression test for #58435.)
- #58912 (Regression test for #58813)
- #58916 (Fix release note problems noticed after merging.)
- #58918 (Regression test added for an async ICE.)
- #58921 (Add an explicit test for issue #50582)
- #58926 (Make the lifetime parameters of tcx consistent.)
- #58931 (Elide invalid method receiver error when it contains TyErr)
- #58940 (Remove JSBackend from config.toml)
- #58950 (Add self to mailmap)
- #58961 (On incorrect cfg literal/identifier, point at the right span)
- #58963 (libstd: implement Error::source for io::Error)
- #58970 (delay_span_bug in wfcheck's ty.lift_to_tcx unwrap)
- #58984 (Teach `-Z treat-err-as-bug` to take a number of errors to emit)
- #59007 (Add a test for invalid const arguments)
Failed merges:
- #58959 (Add release notes for PR #56243)
r? @ghost
Fix segfaults in release build C-variadic fns
`va_start` and `va_end` must be called to initialize/cleanup the
"spoofed" `VaList` in a Rust defined C-variadic function even if
the `VaList` is not used.
r? @alexreg
Fixes: #58980
