Fast path for stalled obligations on self ty
If we see that the `self` type of a goal is an infer var, then don't try to compute the goal at all, since we know that it'll be forced ambiguous.
This is currently only implemented when there are no opaques in the environment. We could extend it to check that the self type is not related to any already defined opaques via subtyping, but I'll leave that as a follow-up.
---
Also stall coerce and subtype predicates if both of their vars are not resolved to concrete types.
---
~~Also, we don't care if the goal is higher-ranked for the sized and copy/clone fast path.~~ pulling this out into another PR.
r? lcnr
doc: Fix inverted meaning in E0783.md
`...` (three dots) was the old way of saying `..=`, which both denote the *inclusive* range, not the *exclusive* one.
canon_abi: make to_erased_extern_abi just a detail in formatting
I think ideally we'd avoid ever printing `CanonAbi` to users, but that needs further changes. Personally I think it's fine for Miri to use the debug printing of `CanonAbi` until we figure that out, but I think others disagree. ;)
r? ``@workingjubilee``
Clean `rustc_attr_parsing/src/lib.rs` documentation
Improves the documentation clarity in `rustc_attr_parsing` by restructuring content with clearer section headers, simplifying explanations of attribute types, making technical descriptions more precise.
r? ``@oli-obk``
Ensure stack in two places that affect s390x
In our Fedora s390x test results, we found two tests that started hitting stack
overflows in the 1.87.0 update. It seems to be related in some part to our use
of PGO as well, probably inlining more into stack frames that were already
recursive. The main points of recursion that I identified were:
- `ui/parser/survive-peano-lesson-queue.rs` in `ThirBuildCx::mirror_exprs`
- `ui/associated-consts/issue-93775.rs` in `Parser::parse_ty`
A couple new `ensure_sufficient_stack` calls will solve these tests.
Replace some `Option<Span>` with `Span` and use DUMMY_SP instead of None
Turns out many locations actually have a span available that we could use, so I used it
Add a new `mismatched-lifetime-syntaxes` lint
The lang-team [discussed this](https://hackmd.io/nf4ZUYd7Rp6rq-1svJZSaQ) and I attempted to [summarize](https://github.com/rust-lang/rust/pull/120808#issuecomment-2701863833) their decision. The summary-of-the-summary is:
- Using two different kinds of syntax for elided lifetimes is confusing. In rare cases, it may even [lead to unsound code](https://github.com/rust-lang/rust/issues/48686)! Some examples:
```rust
// Lint will warn about these
fn(v: ContainsLifetime) -> ContainsLifetime<'_>;
fn(&'static u8) -> &u8;
```
- Matching up references with no lifetime syntax, references with anonymous lifetime syntax, and paths with anonymous lifetime syntax is an exception to the simplest possible rule:
```rust
// Lint will not warn about these
fn(&u8) -> &'_ u8;
fn(&'_ u8) -> &u8;
fn(&u8) -> ContainsLifetime<'_>;
```
- Having a lint for consistent syntax of elided lifetimes will make the [future goal](https://github.com/rust-lang/rust/issues/91639) of warning-by-default for paths participating in elision much simpler.
---
This new lint attempts to accomplish the goal of enforcing consistent syntax. In the process, it supersedes and replaces the existing `elided-named-lifetimes` lint, which means it starts out life as warn-by-default.
#[used] currently is an alias for #[used(linker)] on all platforms
except ELF based ones where it is an alias for #[used(compiler)]. The
latter has surprising behavior and the LLVM LangRef explicitly states
that it "should only be used in rare circumstances, and should not be
exposed to source languages."
The reason #[used] still was an alias to #[used(compiler)] on ELF is
because the gold linker has issues with it. Luckily gold has been
deprecated with GCC 15 and seems to be unable to bootstrap rustc anyway.
As such we shouldn't really care about supporting gold.
Move placeholder handling to a proper preprocessing step
This commit breaks out the logic of placheolder rewriting into its own preprocessing step. It's one of the more boring
parts of #130227.
The only functional change from this is that the preprocessing step (where extra `r: 'static` constraints are added) is performed upstream of Polonius legacy, finally affecting Polonius. That is mostly a by-product, though.
This should be reviewable by anyone in the compiler team, so
r? rust-lang/compiler
Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
`@rustbot` modify labels: rollup
This solve a stack overflow found on Fedora s390x when building
`tests/ui/parser/survive-peano-lesson-queue.rs`. Note that the singular
`mirror_expr` method already has this stack check, but in this case the
plural method was the one recursing too deeply.
x86 (32/64): go back to passing SIMD vectors by-ptr
Fixes https://github.com/rust-lang/rust/issues/139029 by partially reverting https://github.com/rust-lang/rust/pull/135408 and going back to passing SIMD vectors by-ptr on x86. Sadly, by-val confuses the LLVM inliner so much that it's not worth it...
Also fixes https://github.com/rust-lang/rust/issues/141848 by no longer actually using vector registers with the "Rust" ABI.
r? `@tgross35`
Cc `@nikic`
try-job: `test-various*`
try-job: dist-i586-gnu-i586-i686-musl
try-job: x86_64-gnu-nopt
try-job: `x86_64-msvc*`
try-job: `i686-msvc*`
Don't refer to 'local binding' in extern macro.
When it comes from a macro expansion, the user has no clue what 'local binding' the compiler is talking about, if they don't know the expansion of the macro. Better to just say 'temporary value'.
Don't refer to 'this tail expression' in expansion.
The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.
Change `tag_field` to `FieldIdx` in `Variants::Multiple`
It was already available as a generic parameter anyway, and it's not like we'll ever put a tag in the 5-billionth field.
This is a first part of pulling smaller pieces out of rust-lang/rust#138759, so
r? workingjubilee
Ensure query keys are printed with reduced queries
Using `-Z query-dep-graph` and debug assertions leads to an ICE that was originally discovered in rust-lang/rust#141700:
> This isn't an incremental bug per se, but instead a bug that has to do with debug printing query keys when debug assertions and `-Z query-dep-graph` is enabled. We end up printing a const (b/c we're using generic const args here) whose debug printing for -Z query-dep-graph requires invoking the same query cyclically 😃
>
> I've pushed a commit which should fix this.
This isn't related to the standard library changes, but instead b/c it seems to be the first usage of `feature(adt_const_params)` in the standard library that ends up being triggered in incremental tests.
r? oli-obk
Run wfcheck in one big loop instead of per module
Maybe we can merge this big loop in the future with the `par_hir_body_owners` call below and run typeck only on items that didn't fail wfcheck. For now let's just see if perf likes it, as it by itself should be beneficial to parallel rustc
Fix for async drop inside async gen fn
Return value (for yield) is corrected for async drop inside async gen function.
In CFG, when internal async drop future is polled and returned `Poll<()>::Pending`, then async gen resume function returns `Poll<(OptRet)>::Pending`.
Fixesrust-lang/rust#140530
Fix incorrect eq_unspanned in TokenStream
Fixesrust-lang/rust#141522
r? ``@workingjubilee``
should we remove this function?
since it's used in several places, i'd prefer to keep it.
The user has no clue what tail expression the compiler is talking
about: it is an implementation detail of the macro that it uses a block
with tail expression.
Rollup of 8 pull requests
Successful merges:
- rust-lang/rust#136687 (Improve the documentation of `Display` and `FromStr`, and their interactions)
- rust-lang/rust#137306 (Remove `i128` and `u128` from `improper_ctypes_definitions`)
- rust-lang/rust#138699 (build dist for x86_64-pc-solaris and sparcv9-sun-solaris)
- rust-lang/rust#141250 (add s390x z17 target features)
- rust-lang/rust#141467 (make `OsString::new` and `PathBuf::new` unstably const)
- rust-lang/rust#141871 (index: add method for checking range on DenseBitSet)
- rust-lang/rust#141888 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#142000 (bootstrap: don't symlink source dir into stage0 sysroot)
r? `@ghost`
`@rustbot` modify labels: rollup
index: add method for checking range on DenseBitSet
Micro-optimisation that Miri benefits from with the new isolated allocator for native-libs mode. Also possibly just a useful method to have on `DenseBitSet`
