borrowck=migrate must look at parents of closures
This fixes the NLL migration mode (which is the default with edition=2018) to inspect all parents of a closure in addition to the closure itself when looking to see if AST-borrowck issues an error for the given code.
This should be a candidate for beta backport.
Fix#55492
back out bogus `Ok`-wrapping suggestion on `?` arm type mismatch
This suggestion was introduced in #51938 / 6cc78bf8d7 (while introducing different language for type errors coming from `?` rather than a `match`), but it has a lot of false-positives, and incorrect suggestions carry more badness than marginal good suggestions do goodness. I regret not doing this earlier. 😞Resolves#52537, resolves#54578.
r? @estebank
Rollup of 11 pull requests
Successful merges:
- #55148 (Implement FromStr for PathBuf)
- #55185 (path suggestions in Rust 2018 should point out the change in semantics)
- #55191 (Fix sub-variant doc display)
- #55199 (Impl items have generics)
- #55244 (Don't rerun MIR passes when inlining)
- #55252 (Add MaybeUninit::new)
- #55257 (Allow extern statics with an extern type)
- #55389 (Remove unnecessary mut in iterator.find_map documentation example, R…)
- #55406 (Update string.rs)
- #55412 (Fix an ICE in the min_const_fn analysis)
- #55421 (Add ManuallyDrop::take)
path suggestions in Rust 2018 should point out the change in semantics
Fixes#55130.
This commit extends existing path suggestions to link to documentation
on the changed semantics of `use` in Rust 2018.
Fix ordering of nested modules in non-mod.rs mods
Flatten relative offset into directory path before adding inline
(mod x { ... }) module names to the current directory path.
Fix#55094
Don't rerun MIR passes when inlining
Fixes#50411
r? @nikomatsakis
I updated your commit message with additional details. Let me know if any of that is incorrect. I also added the appropriate `compile-flags` directive to the test.
Thanks for you help on this!
cc @RalfJung related to your PR #55086
Partial implementation of uniform paths 2.0 to land before beta
Reimplementation of uniform paths using in-scope resolution rather than canaries is a minor breaking change due to stricter future-proofing, so it needs to be landed before beta or backported later.
I hope to implement at least something until beta so we have less to backport.
r? @Mark-Simulacrum
This suggestion was introduced in #51938 / 6cc78bf8d7 (while
introducing different language for type errors coming from `?` rather
than a `match`), but it has a lot of false-positives (as repeatedly
reported in Issues #52537, #52598, #54578, #55336), and incorrect
suggestions carry more badness than marginal good suggestions do
goodness. Just get rid of it (unless and until someone figures out how
to do it correctly).
Resolves#52537, resolves#54578.
We avoid an ICE by checking for an empty meta-item list before we
index into the meta-items, and leave commentary about where we'd like
to issue unused-attributes lints in the future. Note that empty lint
attributes are already accepted by the stable compiler; generalizing
this to weird reason-only lint attributes seems like the
conservative/consilient generalization.
Vadim Petrochenkov suggested this in review ("an error? just to be
conservative"), and it turns out to be convenient from the
implementer's perspective: in the initial proposed implementation (or
`HEAD~2`, as some might prefer to call it), we were doing an entire
whole iteration over the meta items just to find the reason (before
iterating over them to set the actual lint levels). This way, we can
just peek at the end rather than adding that extra loop (or
restructuring the existing code). The RFC doesn't seem to take a
position on this, and there's some precedent for restricting things to
be at the end of a sequence (we only allow `..` at the end of a struct
pattern, even if it would be possible to let it appear anywhere in the
sequence).
Implement by-value object safety
This PR implements **by-value object safety**, which is part of unsized rvalues #48055. That means, with `#![feature(unsized_locals)]`, you can call a method `fn foo(self, ...)` on trait objects. One aim of this is to enable `Box<FnOnce>` in the near future.
The difficulty here is this: when constructing a vtable for a trait `Foo`, we can't just put the function `<T as Foo>::foo` into the table. If `T` is no larger than `usize`, `self` is usually passed directly. However, as the caller of the vtable doesn't know the concrete `Self` type, we want a variant of `<T as Foo>::foo` where `self` is always passed by reference.
Therefore, when the compiler encounters such a method to be generated as a vtable entry, it produces a newly introduced instance called `InstanceDef::VtableShim(def_id)` (that wraps the original instance). the shim just derefs the receiver and calls the original method. We give different symbol names for the shims by appending `::{{vtable-shim}}` to the symbol path (and also adding vtable-shimness as an ingredient to the symbol hash).
r? @eddyb
This is just for the `reason =` name-value meta-item; the
`#[expect(lint)]` attribute also described in the RFC is a problem for
another day.
The place where we were directly calling `emit()` on a match block
(whose arms returned a mutable reference to a diagnostic-builder) was
admittedly cute, but no longer plausibly natural after adding the
if-let to the end of the `LintSource::Node` arm.
This regards #54503.
NLL: cast causes failure to promote to static
Fixes#55288. See commit messages for more details.
r? @oli-obk
cc @nikomatsakis
cc @pnkfelix
cc @RalfJung
Do not allow moving out of thread local under ast borrowck
AST borrowck failed to prevent moving out of a thread-local static.
This was broken. And it also (sometimes?) caused an ICE during drop elaboration.
Fix#47215Fix#54797
Handle bindings in substructure of patterns with type ascriptions
This attempts to follow the outline described by @nikomatsakis [here](https://github.com/rust-lang/rust/issues/47184#issuecomment-420041056). Its a bit more complicated than expected for two reasons:
1. In general it handles sets of type ascriptions, because such ascriptions can be nested within patterns
2. It has a separate types in the HAIR, `PatternTypeProjections` and `PatternTypeProjection`, which are analogues to the corresponding types in the MIR.
The main reason I added the new HAIR types was because I am worried that the current implementation is inefficent, and asymptotically so: It makes copies of vectors as it descends the patterns, even when those accumulated vectors are never used.
Longer term, I would like to used a linked tree structure for the `PatternTypeProjections` and `PatternTypeProjection`, and save the construction of standalone vectors for the MIR types. I didn't want to block landing this on that hypoethetical revision; but I figured I could at least make the future change easier by differentiating between the two types now.
Oh, one more thing: This doesn't attempt to handle `ref x` (in terms of ensuring that any necessary types are ascribed to `x` in that scenario as well). We should open an issue to investigate supporting that as well. But I didn't want to block this PR on that future work.
Fix#54570
Update the existing NLL `patterns.rs` test accordingly.
includes changes addressing review feedback:
* Added example to docs for `UserTypeProjections` illustrating how we
build up multiple projections when descending into a pattern with
type ascriptions.
* Adapted niko's suggested docs for `UserTypeProjection`.
* Factored out `projection_ty` from more general `projection_ty_core`
(as a drive-by, made its callback an `FnMut`, as I discovered later
that I need that).
* Add note to docs that `PlaceTy.field_ty(..)` does not normalize its result.
* Normalize as we project out `field_ty`.
Rollup of 21 pull requests
Successful merges:
- #54816 (Don't try to promote already promoted out temporaries)
- #54824 (Cleanup rustdoc tests with `@!has` and `@!matches`)
- #54921 (Add line numbers option to rustdoc)
- #55167 (Add a "cheap" mode for `compute_missing_ctors`.)
- #55258 (Fix Rustdoc ICE when checking blanket impls)
- #55264 (Compile the libstd we distribute with -Ccodegen-unit=1)
- #55271 (Unimplement ExactSizeIterator for MIR traversing iterators)
- #55292 (Macro diagnostics tweaks)
- #55298 (Point at macro definition when no rules expect token)
- #55301 (List allowed tokens after macro fragments)
- #55302 (Extend the impl_stable_hash_for! macro for miri.)
- #55325 (Fix link to macros chapter)
- #55343 (rustbuild: fix remap-debuginfo when building a release)
- #55346 (Shrink `Statement`.)
- #55358 (Remove redundant clone (2))
- #55370 (Update mailmap for estebank)
- #55375 (Typo fixes in configure_cmake comments)
- #55378 (rustbuild: use configured linker to build boostrap)
- #55379 (validity: assert that unions are non-empty)
- #55383 (Use `SmallVec` for the queue in `coerce_unsized`.)
- #55391 (bootstrap: clean up a few clippy findings)
Report const eval error inside the query
Functional changes: We no longer warn about bad constants embedded in unused types. This relied on being able to report just a warning, not a hard error on that case, which we cannot do any more now that error reporting is consistently centralized.
r? @RalfJung
fixes#53561
