Rollup of 15 pull requests
Successful merges:
- #116791 (Allow codegen backends to opt-out of parallel codegen)
- #116793 (Allow targets to override default codegen backend)
- #117458 (LLVM Bitcode Linker: A self contained linker for nvptx and other targets)
- #119385 (Fix type resolution of associated const equality bounds (take 2))
- #121438 (std support for wasm32 panic=unwind)
- #121893 (Add tests (and a bit of cleanup) for interior mut handling in promotion and const-checking)
- #122080 (Clarity improvements to `DropTree`)
- #122152 (Improve diagnostics for parenthesized type arguments)
- #122166 (Remove the unused `field_remapping` field from `TypeLowering`)
- #122249 (interpret: do not call machine read hooks during validation)
- #122299 (Store backtrace for `must_produce_diag`)
- #122318 (Revision-related tweaks for next-solver tests)
- #122320 (Use ptradd for vtable indexing)
- #122328 (unix_sigpipe: Replace `inherit` with `sig_dfl` in syntax tests)
- #122330 (bootstrap readme: fix, improve, update)
r? `@ghost`
`@rustbot` modify labels: rollup
unix_sigpipe: Replace `inherit` with `sig_dfl` in syntax tests
The `sig_dfl` variant of the attribute is the most likely variant to be stabilized first, and thus to become the "most allowed" variant of the attribute. Because of this, it is the most appropriate variant to use in syntax tests, because even if the most allowed variant is used, the compiler shall still emit errors if it e.g. is used in the wrong places.
r? ``@davidtwco`` who already [approved ](https://github.com/rust-lang/rust/pull/120832#pullrequestreview-1875075341) this commit in https://github.com/rust-lang/rust/pull/120832.
It would be nice to land the last preparatory commit of that PR before we begin to [rename ](https://github.com/rust-lang/rust/pull/120832#issuecomment-1987023484) things which will of course create a lot of code conflicts.
Revision-related tweaks for next-solver tests
1. Add `ignore-compare-mode-next-solver` to any test that already has explicit `current next` revisions, since the test failures when testing with `--compare-mode=next-solver` will be false positives.
2. Explicitly add revisions to a handful of tests where we expect behavior to diverge.
r? lcnr
Add tests (and a bit of cleanup) for interior mut handling in promotion and const-checking
Basically these are the parts of https://github.com/rust-lang/rust/pull/121786 that can be salvaged.
r? ``@oli-obk``
Fix type resolution of associated const equality bounds (take 2)
Instead of trying to re-resolve the type of assoc const bindings inside the `type_of` query impl in an incomplete manner, transfer the already (correctly) resolved type from `add_predicates_for_ast_type_binding` to `type_of`/`anon_type_of` through query feeding.
---
Together with #118668 (merged) and #121258, this supersedes #118360.
Fixes#118040.
r? ``@ghost``
Run a single huge par_body_owners instead of many small ones after each other.
This improves parallel rustc parallelism by avoiding the bottleneck after each individual `par_body_owners` (because it needs to wait for queries to finish, so if there is one long running one, a lot of cores will be idle while waiting for the single query).
This improves parallel rustc parallelism by avoiding the bottleneck after each individual `par_body_owners` (because it needs to wait for queries to finish, so if there is one long running one, a lot of cores will be idle while waiting for the single query).
Expose the Freeze trait again (unstably) and forbid implementing it manually
non-emoji version of https://github.com/rust-lang/rust/pull/121501
cc #60715
This trait is useful for generic constants (associated consts of generic traits). See the test (`tests/ui/associated-consts/freeze.rs`) added in this PR for a usage example. The builtin `Freeze` trait is the only way to do it, users cannot work around this issue.
It's also a useful trait for building some very specific abstrations, as shown by the usage by the `zerocopy` crate: https://github.com/google/zerocopy/issues/941
cc ```@RalfJung```
T-lang signed off on reexposing this unstably: https://github.com/rust-lang/rust/pull/121501#issuecomment-1969827742
The `sig_dfl` variant of the attribute is the most likely variant to be
stabilized first, and thus to become the "most allowed" variant of the
attribute. Because of this, it is the most appropriate variant to use in
syntax tests, because even if the most allowed variant is used, the
compiler shall still emit errors if it e.g. is used in the wrong places.
diagnostics: Do not suggest using `#[unix_sigpipe]` without a value
Remove `Word` from the `unix_sigpipe` attribute template so that plain `#[unix_sigpipe]` is not included in suggestions of valid forms of the attribute. Also re-arrange diagnostics code slightly to avoid duplicate diagnostics.
Tracking issue is https://github.com/rust-lang/rust/issues/97889.
Detect typos for compiletest test directives
Checks directives against a known list of compiletest directives collected during migration from legacy-style compiletest directives. A suggestion for the best matching known directive will be made if an invalid directive is found.
This PR does not attempt to implement checks for Makefile directives because they still have the problem of regular comments and directives sharing the same comment prefix `#`.
Closes#83551.
Remove `Word` from the `unix_sigpipe` attribute template so that plain
`#[unix_sigpipe]` is not included in suggestions of valid forms of the
attribute. Also re-arrange diagnostics code slightly to avoid duplicate
diagnostics.
Vec::try_with_capacity
Related to #91913
Implements try_with_capacity for `Vec`, `VecDeque`, and `String`. I can follow it up with more collections if desired.
`Vec::try_with_capacity()` is functionally equivalent to the current stable:
```rust
let mut v = Vec::new();
v.try_reserve_exact(n)?
```
However, `try_reserve` calls non-inlined `finish_grow`, which requires old and new `Layout`, and is designed to reallocate memory. There is benefit to using `try_with_capacity`, besides syntax convenience, because it generates much smaller code at the call site with a direct call to the allocator. There's codegen test included.
It's also a very desirable functionality for users of `no_global_oom_handling` (Rust-for-Linux), since it makes a very commonly used function available in that environment (`with_capacity` is used much more frequently than all `(try_)reserve(_exact)`).
Eagerly translate `HelpUseLatestEdition` in parser diagnostics
Fixes#122130.
This makes me suspicious of these other two usage of `add_to_diagnostic()`. Would they *also* crash? I haven't attempted to construct test cases for them.
```
compiler/rustc_parse/src/parser/expr.rs
3453: errors::HelpUseLatestEdition::new().add_to_diagnostic(e);
compiler/rustc_hir_typeck/src/expr.rs
2603: HelpUseLatestEdition::new().add_to_diagnostic(&mut err);
```
This also seems like a footgun?
Misc improvements to non local defs lint implementation
This PR is a collection of small improvements I found when I [needlessly tried](https://www.github.com/rust-lang/rust/pull/120393#issuecomment-1971787475) to fix a "perf-regression" in the lint implementation.
I recommend looking at each commit individually.
Lint singleton gaps after exclusive ranges
In the discussion to stabilize exclusive range patterns (https://github.com/rust-lang/rust/issues/37854), it has often come up that they're likely to cause off-by-one mistakes. We already have the `overlapping_range_endpoints` lint, so I [proposed](https://github.com/rust-lang/rust/issues/37854#issuecomment-1845580712) a lint to catch the complementary mistake.
This PR adds a new `non_contiguous_range_endpoints` lint that catches likely off-by-one errors with exclusive range patterns. Here's the idea (see the test file for more examples):
```rust
match x {
0..10 => ..., // WARN: this range doesn't match `10_u8` because `..` is an exclusive range
11..20 => ..., // this could appear to continue range `0_u8..10_u8`, but `10_u8` isn't matched by either of them
_ => ...,
}
// help: use an inclusive range instead: `0_u8..=10_u8`
```
More precisely: for any exclusive range `lo..hi`, if `hi+1` is matched by another range but `hi` isn't, we suggest writing an inclusive range `lo..=hi` instead. We also catch `lo..T::MAX`.
Don't ICE if we collect no RPITITs unless there are no unification errors
Move an assertion in `collect_return_position_impl_trait_in_trait_tys` to after the `ObligationCtxt::eq` calls, so that we only assert and ICE if we have unification errors.
Fixes#121468
Merge `collect_mod_item_types` query into `check_well_formed`
follow-up to https://github.com/rust-lang/rust/pull/121154
this removes more potential parallel-compiler bottlenecks and moves diagnostics for the same items next to each other, instead of grouping diagnostics by analysis kind
Use `ControlFlow` in visitors.
Follow up to #121256
This does have a few small behaviour changes in some diagnostic output where the visitor will now find the first match rather than the last match. The change in `find_anon_types.rs` has the only affected test. I don't see this being an issue as the last occurrence isn't any better of a choice than the first.
