about summary refs log tree commit diff
path: root/compiler/rustc_middle/src/ty
AgeCommit message (Collapse)AuthorLines
2025-04-13Initial `UnsafePinned`/`UnsafeUnpin` impl [Part 1: Libs]Sky-0/+13
2025-04-12store the kind of pattern adjustments in `pat_adjustments`dianne-3/+35
This allows us to better distinguish builtin and overloaded implicit dereferences.
2025-04-12Move FlagComputation, PatternKind, and TypeWalker to rustc_type_irjackh726-595/+93
2025-04-12don't store opaque info during encodingbohan-1/+1
2025-04-11Rollup merge of #139662 - nnethercote:tweak-DefPathData, r=compiler-errorsJacob Pratt-3/+3
Tweak `DefPathData` Some improvements in and around `DefPathData`, following on from #137977. r? `@spastorino`
2025-04-11Auto merge of #139453 - compiler-errors:incr, r=jieyouxubors-2/+2
Prepend temp files with per-invocation random string to avoid temp filename conflicts https://github.com/rust-lang/rust/issues/139407 uncovered a very subtle unsoundness with incremental codegen, failing compilation sessions (due to assembler errors), and the "prefer hard linking over copying files" strategy we use in the compiler for file management. Specifically, imagine we're building a single file 3 times, all with `-Csave-temps -Cincremental=...`. Let's call the object file we're building for the codegen unit for `main` "`XXX.o`" just for clarity since it's probably some gigantic hash name: ``` #[inline(never)] #[cfg(any(rpass1, rpass3))] fn a() -> i32 { 0 } #[cfg(any(cfail2))] fn a() -> i32 { 1 } fn main() { evil::evil(); assert_eq!(a(), 0); } mod evil { #[cfg(any(rpass1, rpass3))] pub fn evil() { unsafe { std::arch::asm!("/* */"); } } #[cfg(any(cfail2))] pub fn evil() { unsafe { std::arch::asm!("missing"); } } } ``` Session 1 (`rpass1`): * Type-check, borrow-check, etc. * Serialize the dep graph to the incremental working directory `.../s-...-working/`. * Codegen object file to a temp file `XXX.rcgu.o` which is spit out in the cwd. * Hard-link[^1] `XXX.rcgu.o` to the incremental working directory `.../s-...-working/XXX.o`. * Save-temps option means we don't delete `XXX.rgcu.o`. * Link the binary and stuff. * Finalize[^2] the working incremental session by renaming `.../s-...-working` to ` s-...-asjkdhsjakd` (some other finalized incr comp session dir name). Session 2 (`cfail2`): * Load artifacts from the previous *finalized* incremental session, namely the dep graph. * Type-check, borrow-check, etc. since the file has changed, so most dep graph nodes are red. * Serialize the dep graph to the incremental working directory `.../s-...-working/`. * Codegen object file to a temp file `XXX.rcgu.o`. **HERE IS THE PROBLEM**: The hard-link is still set up to point to the inode from `XXX.o` from the first session, so this also modifies the `XXX.o` in the previous finalized session directory. * Codegen emits an error b/c `missing` is not an instruction, so we abort before finalizing the incremental session. Specifically, this means that the *previous* session is the last finalized session. Session 3 (`rpass3`): * Load artifacts from the previous *finalized* incremental session, namely the dep graph. NOTE that this is from session 1. * All the dep graph nodes are green since we are basically replaying session 1. * codegen object file `XXX.o`, which is detected as *reused* from session 1 since dep nodes were green. That means we **reuse** `XXX.o` which had been dirtied from session 2. * Link the binary and stuff. This results in a binary which reuses some of the build artifacts from session 2, but thinks it's from session 1. At this point, I hope it's clear to see that the incremental results from session 1 were dirtied from session 2, but we reuse them as if session 1 was the previous (finalized) incremental session we ran. This is at best really buggy, and at worst **unsound**. This isn't limited to `-C save-temps`, since there are other combinations of flags that may keep around temporary files (hard linked) in the working directory (like `-C debuginfo=1 -C split-debuginfo=unpacked` on darwin, for example). --- This PR implements a fix which is to prepend temp filenames with a random string that is generated per invocation of rustc. This string is not *deterministic*, but temporary files are transient anyways, so I don't believe this is a problem. That means that temp files are now something like... `{crate-name}.{cgu}.{invocation_temp}.rcgu.o`, where `{invocation_temp}` is the new temporary string we generate per invocation of rustc. Fixes https://github.com/rust-lang/rust/issues/139407 [^1]: https://github.com/rust-lang/rust/blob/175dcc7773d65c1b1542c351392080f48c05799f/compiler/rustc_fs_util/src/lib.rs#L60 [^2]: https://github.com/rust-lang/rust/blob/175dcc7773d65c1b1542c351392080f48c05799f/compiler/rustc_incremental/src/persist/fs.rs#L1-L40
2025-04-11Introduce `DefPathData::AnonAssocTy`.Nicholas Nethercote-3/+3
PR #137977 changed `DefPathData::TypeNs` to contain `Option<Symbol>` to account for RPITIT assoc types being anonymous. This commit changes it back to `Symbol` and gives anonymous assoc types their own variant. It makes things a bit nicer overall.
2025-04-11Improve `AssocItem::descr`.Nicholas Nethercote-2/+4
The commit adds "associated" to the description of associated types and associated consts, to match the description of associated functions. This increases error message precision and consistency with `AssocKind::fmt`. The commit also notes an imperfection in `AssocKind::fmt`; fixing this imperfection is possible but beyond the scope of this PR.
2025-04-10Rollup merge of #139510 - nnethercote:name-to-ident, r=fee1-deadMatthias Krüger-12/+15
Rename some `name` variables as `ident`. It bugs me when variables of type `Ident` are called `name`. It leads to silly things like `name.name`. `Ident` variables should be called `ident`, and `name` should be used for variables of type `Symbol`. This commit improves things by by doing `s/name/ident/` on a bunch of `Ident` variables. Not all of them, but a decent chunk. r? `@fee1-dead`
2025-04-10Address review comments.Nicholas Nethercote-4/+7
2025-04-10Rename some `name` variables as `ident`.Nicholas Nethercote-12/+12
It bugs me when variables of type `Ident` are called `name`. It leads to silly things like `name.name`. `Ident` variables should be called `ident`, and `name` should be used for variables of type `Symbol`. This commit improves things by by doing `s/name/ident/` on a bunch of `Ident` variables. Not all of them, but a decent chunk.
2025-04-09Use a query rather than recomputing the tail repeatedlyMichael Goulet-37/+4
2025-04-09Rigidly project missing item due to guaranteed impossible sized predicateMichael Goulet-0/+37
2025-04-09Rollup merge of #139364 - Kohei316:feat/doc-hidden-suggestion, r=nnethercoteMatthias Krüger-0/+7
Make the compiler suggest actual paths instead of visible paths if the visible paths are through any doc hidden path. close #127011 Currently, when emitting a diagnostic about a valid trait, the compiler suggestes using visible paths of the trait even if they are through a doc hidden path. This PR updates the compiler to suggest actual paths in these cases.
2025-04-09re-use sized fast pathDavid Wood-7/+7
There's an existing fast path for the `type_op_prove_predicate` predicate, checking for trivially `Sized` types, which can be re-used when evaluating obligations within queries. This should improve performance, particularly in anticipation of new sizedness traits being added which can take advantage of this.
2025-04-08Auto merge of #139536 - matthiaskrgr:rollup-j6goald, r=matthiaskrgrbors-37/+26
Rollup of 7 pull requests Successful merges: - #139476 (rm `RegionInferenceContext::var_infos`) - #139485 (compiletest: Stricter parsing for diagnostic kinds) - #139491 (Update books) - #139500 (document panic behavior of Vec::resize and Vec::resize_with) - #139501 (Fix stack overflow in exhaustiveness due to recursive HIR opaque hidden types) - #139504 (add missing word in doc comment) - #139509 (clean: remove Deref<Target=RegionKind> impl for Region and use `.kind()`) r? `@ghost` `@rustbot` modify labels: rollup
2025-04-08clean code: remove Deref<Target=RegionKind> impl for Region and use `.kind()`xizheyin-37/+26
Signed-off-by: xizheyin <xizheyin@smail.nju.edu.cn>
2025-04-08borrowck typeck children together with their parentlcnr-1/+1
2025-04-07Simplify temp path creation a bitMichael Goulet-2/+2
2025-04-07Rollup merge of #139461 - compiler-errors:significant-drop-span, r=oli-obkStuart Cook-18/+4
Stop calling `source_span` query in significant drop order code `source_span` is only meant for incremental tracking. I don't really think we need to highlight the whole drop impl span anyways; it can be quite large. r? oli-obk
2025-04-07Rollup merge of #139455 - Skgland:remove_rust-intrinsic_ABI, r=oli-obkStuart Cook-9/+4
Remove support for `extern "rust-intrinsic"` blocks Part of rust-lang/rust#132735 Looked manageable and there didn't appear to have been progress in the last two weeks, so decided to give it a try.
2025-04-06Stop calling source_span query in significant drop order codeMichael Goulet-18/+4
2025-04-06remove compiler support for `extern "rust-intrinsic"` blocksSkgland-9/+4
2025-04-06Rollup merge of #139414 - Adamkob12:fix_typo_raw_list, r=NadrierilGuillaume Gomez-3/+3
Fix typo in `RawList`'s documentation
2025-04-05formatAdam Kobzan-3/+3
2025-04-05Fix TypoAdam Kobzan-2/+2
2025-04-05Auto merge of #139292 - compiler-errors:folder-experiment-7, r=lqdbors-1/+23
Folder experiment: Micro-optimize RegionEraserVisitor **NOTE:** This is one of a series of perf experiments that I've come up with while sick in bed. I'm assigning them to lqd b/c you're a good reviewer and you'll hopefully be awake when these experiments finish, lol. r? lqd The region eraser is very hot, so let's see if we can avoid erasing types (and visiting consts and preds that don't have region-ful types) unnecessarily.
2025-04-05Auto merge of #139281 - petrochenkov:ctxtdecod6, r=wesleywiserbors-1/+1
hygiene: Avoid recursion in syntax context decoding #139241 has two components - Avoiding recursion during syntax context decoding - Encoding/decoding only the non-redundant data, and recalculating the redundant data again during decoding Both of these parts may influence compilation times, possibly in opposite directions. So this PR contains only the first part to evaluate its effect in isolation.
2025-04-05Rollup merge of #138950 - yaahc:svh-metrics-name, r=bjorn3Stuart Cook-0/+5
replace extra_filename with strict version hash in metrics file names Should resolve the potential issue of overwriting metrics from the same crate when compiled with different features or flags. r? `````@estebank````` try-job: test-various
2025-04-04Auto merge of #139390 - matthiaskrgr:rollup-l64euwx, r=matthiaskrgrbors-70/+10
Rollup of 9 pull requests Successful merges: - #139041 (Remove `rustc_middle::ty::util::ExplicitSelf`.) - #139328 (Fix 2024 edition doctest panic output) - #139339 (unstable book: document tait) - #139348 (AsyncDestructor: replace fields with impl_did) - #139353 (Fix `Debug` impl for `LateParamRegionKind`.) - #139366 (ToSocketAddrs: fix typo) - #139374 (Use the span of the whole bound when the diagnostic talks about a bound) - #139378 (Use target-agnostic LLD flags in bootstrap for `use-lld`) - #139384 (Add `compiletest` adhoc_group for `r? compiletest`) r? `@ghost` `@rustbot` modify labels: rollup
2025-04-04Rollup merge of #139353 - nnethercote:LateAnon, r=compiler-errorsMatthias Krüger-4/+4
Fix `Debug` impl for `LateParamRegionKind`. It uses `Br` prefixes which are inappropriate and appear to have been incorrectly copy/pasted from the `Debug` impl for `BoundRegionKind`. r? `@BoxyUwU`
2025-04-04Rollup merge of #139348 - meithecatte:async-destructor-minify, r=petrochenkovMatthias Krüger-17/+6
AsyncDestructor: replace fields with impl_did The future and ctor fields aren't actually used, and the way they are extracted is obviously wrong – swapping the order of the items in the source code will give wrong results. Instead, store just the LocalDefId of the impl, which is enough for the only use of this data.
2025-04-04Rollup merge of #139041 - nnethercote:rm-rustc_middle-ty-util-ExplicitSelf, ↵Matthias Krüger-49/+0
r=BoxyUwU Remove `rustc_middle::ty::util::ExplicitSelf`. It's an old (2017 or earlier) type that describes a `self` receiver. It's only used in `rustc_hir_analysis` for two error messages, and much of the complexity isn't used. I suspect it used to be used for more things. This commit removes it, and moves a greatly simplified version of the `determine` method into `rustc_hir_analysis`, renamed as `get_self_string`. The big comment on the method is removed because it no longer seems relevant. r? `@BoxyUwU`
2025-04-04Auto merge of #138785 - lcnr:typing-mode-borrowck, r=compiler-errors,oli-obkbors-31/+52
add `TypingMode::Borrowck` Shares the first commit with #138499, doesn't really matter which PR to land first :blush: :grin: Introduces `TypingMode::Borrowck` which unlike `TypingMode::Analysis`, uses the hidden type computed by HIR typeck as the initial value of opaques instead of an unconstrained infer var. This is a part of https://github.com/rust-lang/types-team/issues/129. Using this new `TypingMode` is unfortunately a breaking change for now, see tests/ui/impl-trait/non-defining-uses/as-projection-term.rs. Using an inference variable as the initial value results in non-defining uses in the defining scope. We therefore only enable it if with `-Znext-solver=globally` or `-Ztyping-mode-borrowck` To do that the PR contains the following changes: - `TypeckResults::concrete_opaque_type` are already mapped to the definition of the opaque type - writeback now checks that the non-lifetime parameters of the opaque are universal - for this, `fn check_opaque_type_parameter_valid` is moved from `rustc_borrowck` to `rustc_trait_selection` - we add a new `query type_of_opaque_hir_typeck` which, using the same visitors as MIR typeck, attempts to merge the hidden types from HIR typeck from all defining scopes - done by adding a `DefiningScopeKind` flag to toggle between using borrowck and HIR typeck - the visitors stop checking that the MIR type matches the HIR type. This is trivial as the HIR type are now used as the initial hidden types of the opaque. This check is useful as a safeguard when not using `TypingMode::Borrowck`, but adding it to the new structure is annoying and it's not soundness critical, so I intend to not add it back. - add a `TypingMode::Borrowck` which behaves just like `TypingMode::Analysis` except when normalizing opaque types - it uses `type_of_opaque_hir_typeck(opaque)` as the initial value after replacing its regions with new inference vars - it uses structural lookup in the new solver fixes #112201, fixes #132335, fixes #137751 r? `@compiler-errors` `@oli-obk`
2025-04-04Make the compiler suggest actual paths instead of visible paths if the ↵morine0122-0/+7
visible paths are through any doc hidden path.
2025-04-04Rollup merge of #139349 - meithecatte:destructor-constness, r=compiler-errorsMatthias Krüger-0/+5
adt_destructor: sanity-check returned item Fixes #139278
2025-04-04Rollup merge of #139313 - oli-obk:push-uzvmpxqyvrzp, r=compiler-errorsMatthias Krüger-44/+3
Deduplicate some `rustc_middle` function bodies by calling the `rustc_type_ir` equivalent Maybe in the future we can use method delegation, but I'd rather avoid that for now (I don't even know if it can do that already)
2025-04-04Fix `Debug` impl for `LateParamRegionKind`.Nicholas Nethercote-4/+4
It uses `Br` prefixes which are inappropriate and appear to have been incorrectly copy/pasted from the `Debug` impl for `BoundRegionKind`.
2025-04-04adt_destructor: sanity-check returned itemMaja Kądziołka-0/+5
Fixes #139278
2025-04-04AsyncDestructor: replace fields with impl_didMaja Kądziołka-17/+6
The future and ctor fields aren't actually used, and the way they are extracted is obviously wrong – swapping the order of the items in the source code will give wrong results. Instead, store just the LocalDefId of the impl, which is enough for the only use of this data.
2025-04-04Auto merge of #120706 - Bryanskiy:leak, r=lcnrbors-0/+23
Initial support for auto traits with default bounds This PR is part of ["MCP: Low level components for async drop"](https://github.com/rust-lang/compiler-team/issues/727) Tracking issue: #138781 Summary: https://github.com/rust-lang/rust/pull/120706#issuecomment-1934006762 ### Intro Sometimes we want to use type system to express specific behavior and provide safety guarantees. This behavior can be specified by various "marker" traits. For example, we use `Send` and `Sync` to keep track of which types are thread safe. As the language develops, there are more problems that could be solved by adding new marker traits: - to forbid types with an async destructor to be dropped in a synchronous context a trait like `SyncDrop` could be used [Async destructors, async genericity and completion futures](https://sabrinajewson.org/blog/async-drop). - to support [scoped tasks](https://without.boats/blog/the-scoped-task-trilemma/) or in a more general sense to provide a [destruction guarantee](https://zetanumbers.github.io/book/myosotis.html) there is a desire among some users to see a `Leak` (or `Forget`) trait. - Withoutboats in his [post](https://without.boats/blog/changing-the-rules-of-rust/) reflected on the use of `Move` trait instead of a `Pin`. All the traits proposed above are supposed to be auto traits implemented for most types, and usually implemented automatically by compiler. For backward compatibility these traits have to be added implicitly to all bound lists in old code (see below). Adding new default bounds involves many difficulties: many standard library interfaces may need to opt out of those default bounds, and therefore be infected with confusing `?Trait` syntax, migration to a new edition may contain backward compatibility holes, supporting new traits in the compiler can be quite difficult and so forth. Anyway, it's hard to evaluate the complexity until we try the system on a practice. In this PR we introduce new optional lang items for traits that are added to all bound lists by default, similarly to existing `Sized`. The examples of such traits could be `Leak`, `Move`, `SyncDrop` or something else, it doesn't matter much right now (further I will call them `DefaultAutoTrait`'s). We want to land this change into rustc under an option, so it becomes available in bootstrap compiler. Then we'll be able to do standard library experiments with the aforementioned traits without adding hundreds of `#[cfg(not(bootstrap))]`s. Based on the experiments, we can come up with some scheme for the next edition, in which such bounds are added in a more targeted way, and not just everywhere. Most of the implementation is basically a refactoring that replaces hardcoded uses of `Sized` with iterating over a list of traits including both `Sized` and the new traits when `-Zexperimental-default-bounds` is enabled (or just `Sized` as before, if the option is not enabled). ### Default bounds for old editions All existing types, including generic parameters, are considered `Leak`/`Move`/`SyncDrop` and can be forgotten, moved or destroyed in generic contexts without specifying any bounds. New types that cannot be, for example, forgotten and do not implement `Leak` can be added at some point, and they should not be usable in such generic contexts in existing code. To both maintain this property and keep backward compatibility with existing code, the new traits should be added as default bounds _everywhere_ in previous editions. Besides the implicit `Sized` bound contexts that includes supertrait lists and trait lists in trait objects (`dyn Trait1 + ... + TraitN`). Compiler should also generate implicit `DefaultAutoTrait` implementations for foreign types (`extern { type Foo; }`) because they are also currently usable in generic contexts without any bounds. #### Supertraits Adding the new traits as supertraits to all existing traits is potentially necessary, because, for example, using a `Self` param in a trait's associated item may be a breaking change otherwise: ```rust trait Foo: Sized { fn new() -> Option<Self>; // ERROR: `Option` requires `DefaultAutoTrait`, but `Self` is not `DefaultAutoTrait` } // desugared `Option` enum Option<T: DefaultAutoTrait + Sized> { Some(T), None, } ``` However, default supertraits can significantly affect compiler performance. For example, if we know that `T: Trait`, the compiler would deduce that `T: DefaultAutoTrait`. It also implies proving `F: DefaultAutoTrait` for each field `F` of type `T` until an explicit impl is be provided. If the standard library is not modified, then even traits like `Copy` or `Send` would get these supertraits. In this PR for optimization purposes instead of adding default supertraits, bounds are added to the associated items: ```rust // Default bounds are generated in the following way: trait Trait { fn foo(&self) where Self: DefaultAutoTrait {} } // instead of this: trait Trait: DefaultAutoTrait { fn foo(&self) {} } ``` It is not always possible to do this optimization because of backward compatibility: ```rust pub trait Trait<Rhs = Self> {} pub trait Trait1 : Trait {} // ERROR: `Rhs` requires `DefaultAutoTrait`, but `Self` is not `DefaultAutoTrait` ``` or ```rust trait Trait { type Type where Self: Sized; } trait Trait2<T> : Trait<Type = T> {} // ERROR: `???` requires `DefaultAutoTrait`, but `Self` is not `DefaultAutoTrait` ``` Therefore, `DefaultAutoTrait`'s are still being added to supertraits if the `Self` params or type bindings were found in the trait header. #### Trait objects Trait objects requires explicit `+ Trait` bound to implement corresponding trait which is not backward compatible: ```rust fn use_trait_object(x: Box<dyn Trait>) { foo(x) // ERROR: `foo` requires `DefaultAutoTrait`, but `dyn Trait` is not `DefaultAutoTrait` } // implicit T: DefaultAutoTrait here fn foo<T>(_: T) {} ``` So, for a trait object `dyn Trait` we should add an implicit bound `dyn Trait + DefaultAutoTrait` to make it usable, and allow relaxing it with a question mark syntax `dyn Trait + ?DefaultAutoTrait` when it's not necessary. #### Foreign types If compiler doesn't generate auto trait implementations for a foreign type, then it's a breaking change if the default bounds are added everywhere else: ```rust // implicit T: DefaultAutoTrait here fn foo<T: ?Sized>(_: &T) {} extern "C" { type ExternTy; } fn forward_extern_ty(x: &ExternTy) { foo(x); // ERROR: `foo` requires `DefaultAutoTrait`, but `ExternTy` is not `DefaultAutoTrait` } ``` We'll have to enable implicit `DefaultAutoTrait` implementations for foreign types at least for previous editions: ```rust // implicit T: DefaultAutoTrait here fn foo<T: ?Sized>(_: &T) {} extern "C" { type ExternTy; } impl DefaultAutoTrait for ExternTy {} // implicit impl fn forward_extern_ty(x: &ExternTy) { foo(x); // OK } ``` ### Unresolved questions New default bounds affect all existing Rust code complicating an already complex type system. - Proving an auto trait predicate requires recursively traversing the type and proving the predicate for it's fields. This leads to a significant performance regression. Measurements for the stage 2 compiler build show up to 3x regression. - We hope that fast path optimizations for well known traits could mitigate such regressions at least partially. - New default bounds trigger some compiler bugs in both old and new trait solver. - With new default bounds we encounter some trait solver cycle errors that break existing code. - We hope that these cases are bugs that can be addressed in the new trait solver. Also migration to a new edition could be quite ugly and enormous, but that's actually what we want to solve. For other issues there's a chance that they could be solved by a new solver.
2025-04-03Deduplicate some `rustc_middle` function bodies by calling the ↵Oli Scherer-44/+3
`rustc_type_ir` equivalent
2025-04-03Initial support for auto traits with default boundsBryanskiy-0/+23
2025-04-03Make LevelAndSource a structOli Scherer-6/+6
2025-04-03add `TypingMode::Borrowck`lcnr-31/+52
2025-04-03Micro-optimize RegionEraserVisitorMichael Goulet-1/+23
2025-04-03hygiene: Avoid recursion in syntax context decodingVadim Petrochenkov-1/+1
2025-04-02Auto merge of #139269 - matthiaskrgr:rollup-pk78gig, r=matthiaskrgrbors-7/+0
Rollup of 6 pull requests Successful merges: - #138992 (literal pattern lowering: use the pattern's type instead of the literal's in `const_to_pat`) - #139211 (interpret: add a version of run_for_validation for &self) - #139235 (`AstValidator` tweaks) - #139237 (Add a dep kind for use of the anon node with zero dependencies) - #139260 (Add dianqk to codegen reviewers) - #139264 (Fix two incorrect turbofish suggestions) r? `@ghost` `@rustbot` modify labels: rollup
2025-04-02Rollup merge of #138992 - dianne:simplify-byte-string-to-pat, r=oli-obkMatthias Krüger-7/+0
literal pattern lowering: use the pattern's type instead of the literal's in `const_to_pat` This has two purposes: - First, it enables removing the `treat_byte_string_as_slice` fields from `TypeckResults` and `ConstToPat`. A byte string pattern's type will be `&[u8]` when matching on a slice reference, so `const_to_pat` will lower it to a slice ref pattern. I believe this is tested by `tests/ui/match/pattern-deref-miscompile.rs`. - Second, it will simplify the implementation of byte string literals in deref patterns. If byte string patterns can be given the type `[u8; N]` or `[u8]` during HIR typeck, then nothing needs to be changed in `const_to_pat` in order to lower the patterns `deref!(b"..."): Vec<u8>` and `deref!(b"..."): Box<[u8; 3]>`. Implementation-wise, this uses `lit_to_const` to make a const with the pattern's type and the literal's valtree; that feels to me like the best way to make sure that the valtree representations of the pattern type and literal are the same. Though it may necessitate later changes to `lit_to_const` to accommodate giving byte string literal patterns non-reference types—would that be reasonable? This unfortunately doesn't work for the `string_deref_patterns` feature (since that gives string literal patterns the `String` type), so I added a workaround for that. However, once `deref_patterns` supports string literals, it may be able to replace `string_deref_patterns`; the special case for `String` can removed at that point. r? ``@oli-obk``
2025-04-02Rollup merge of #139232 - nnethercote:remove-Map-5, r=ZalatharTakayuki Maeda-6/+6
Move methods from `Map` to `TyCtxt`, part 5. This eliminates all methods on `Map`. Actually removing `Map` will occur in a follow-up PR. A follow-up to #137504. r? `@Zalathar`