mGCA: Make trait object types with type-level associated consts dyn compatible
Under feature `min_generic_const_args` (mGCA) (rust-lang/rust#132980), render traits with non-parametrized type-level associated constants (i.e., `#[type_const]` ones) dyn compatible but force the user to specify all type-level associated consts in the trait object type via bindings (either directly, via supertrait bounds and/or behind trait aliases) just like associated types, their sibling.
Fixesrust-lang/rust#130300 (feature request).
Fixesrust-lang/rust#136063 (bug).
Fixesrust-lang/rust#137260 (bug).
Fixesrust-lang/rust#137514 (bug).
While I'm accounting for most illegal `Self` references via const projections & params, I'm intentionally ignoring RUST-123140 (and duplicates) in this PR which is to be tackled some other time.
Additional context: Crate `rustc-demangle` had to be updated to fix v0 demangling. I've patched it in PR https://github.com/rust-lang/rustc-demangle/pull/87 which was was released in version 0.1.27 via PR https://github.com/rust-lang/rustc-demangle/pull/88.
compiler: upgrade to hashbrown 0.16.1
See also rust-lang/rust#135634, rust-lang/rust#149159, and rust-lang/hashbrown#662.
This includes an in-tree upgrade of `indexmap` as well, which uses the
new `HashTable` buckets API internally, hopefully impacting performance
for the better.
And finally, we can remove `#[rustc_unsafe_specialization_marker]` on `Copy`!
cc @joboet
r? @Amanieu
rustc_errors: Add (heuristic) Syntax Highlighting for `rustc --explain`
This PR adds a feature that enables `rustc --explain <error>` to have syntax highlighted code blocks. Due to performance, size and complexity constraints, the highlighter is very heuristc, relying on conventions for capitalizations and such to infer what an identifier represents. The details for the implementation are specified below.
# Changes
1. Change `term::entrypoint` to `term::entrypoint_with_formatter`, which takes an optional third argument, which is a function pointer to a formatter. ([compiler/rustc_errors/src/markdown/mod.rs](https://github.com/rust-lang/rust/compare/main...JayanAXHF:rust:rustc_colored_explain?expand=1#diff-a6e139cadbc2e6922d816eb08f9e2c7b48304d09e6588227e2b70215c4f0725c))
2. Change `MdStream::write_anstream_buf` to be a wrapper around a new function, `MdStream::write_anstream_buf_with_formatter`, which takes a function pointer to a formatter. ([compiler/rustc_errors/src/markdown/mod.rs](https://github.com/rust-lang/rust/compare/main...JayanAXHF:rust:rustc_colored_explain?expand=1#diff-a6e139cadbc2e6922d816eb08f9e2c7b48304d09e6588227e2b70215c4f0725c))
3. Change [`compiler/rustc_driver_impl/src/lib.rs`](https://github.com/rust-lang/rust/compare/main...JayanAXHF:rust:rustc_colored_explain?expand=1#diff-39877a2556ea309c89384956740d5892a59cef024aa9473cce16bbdd99287937) to call `MdStream::write_anstream_buf_with_formatter` instead of `MdStream::write_anstream_buf`.
4. Add a `compiler/rustc_driver_impl/src/highlighter.rs` file, which contains the actual syntax highlighter.
# Implementation Details
1. The highlighter starts from the `highlight` function defined in `compiler/rustc_driver_impl/src/highlighter.rs`. It creates a new instance of the `Highlighter` struct, and calls its `highlight_rustc_lexer` function to start highlighting.
2. The `highlight_rustc_lexer` function uses `rustc_lexer` to lex the code into `Token`s. `rustc_lexer` was chosen since it preserves the newlines after scanning.
3. Based on the kind of token (`TokenKind`), we color the corresponding lexeme.
## Highlighter Implementation
### Identifiers
1. All identifiers that match a (non-exhaustive and minimal) list of keywords are coloured magenta.
2. An identifier that begins with a capital letter is assumed as a type. There is no distinction between a `Trait` and a type, since that would involve name resolution, and the parts of `rustc` that perform name resolution on code do not preserve the original formatting. (An attempt to use `rustc_parse`'s lexer and `TokenStream` was made, which was then printed with the pretty printer, but failed to preserve the formatting and was generally more complex to work with)
3. An identifier that is immediately followed by a parenthesis is recognized as a function identifier, and coloured blue.
## Literals
5. A `String` literal (or its corresponding `Raw`, `C` and `Byte` versions) is colored green.
6. All other literals are colored bright red (orange-esque)
## Everything Else
Everything else is colored bright white and dimmed, to create a grayish colour.
---
# Demo
<img width="1864" height="2136" alt="image" src="https://github.com/user-attachments/assets/b17d3a71-e641-4457-be85-5e5b1cea2954" />
<caption> Command: <code>rustc --explain E0520</code> </caption>
---
This description was not generated by an LLM (:p)
cc: @bjorn3
This commit adds a heuristics-based syntax highlighter for the `rustc
--explain` command. It uses `rsutc_lexer`'s lexer to parse input in
tokens, and matches on them to determine their color.
See also #135634, #149159, and rust-lang/hashbrown#662.
This includes an in-tree upgrade of `indexmap` as well, which uses the
new `HashTable` buckets API internally, hopefully impacting performance
for the better!
Update `literal-escaper` version to `0.0.7`
It removes the `std` dependency for this crate (which doesn't change anything for rustc 😄 ).
cc @bjorn3
r? @Urgau
Ensure that static initializers are acyclic for NVPTX
NVPTX does not support cycles in static initializers (see rust-lang/rust#146787). LLVM produces an error when attempting to generate code for such constructs, like self-referential structs.
To avoid LLVM UB, we emit a post-monomorphization error on the Rust side before reaching codegen.
This is achieved by analyzing a subgraph of the "mono item graph" that only contains statics.
1. Calculate the strongly connected components (SCCs) of the graph.
2. Check for cycles (more than one node in an SCC or one node that references itself).
NVPTX does not support cycles in static initializers. LLVM produces an error when attempting to codegen such constructs (like self referential structs).
To not produce LLVM UB we instead emit a post-monomorphization error on
Rust side before reaching codegen.
This is achieved by analysing a subgraph of the "mono item graph" that
only contains statics:
1. Calculate the strongly connected components (SCCs) of the graph
2. Check for cycles (more than one node in a SCC or exactly one node
which references itself)
resolve: Preserve binding scopes in ambiguity errors
It allows to get rid of `AmbiguityErrorMisc`, `Flags` and `extern_prelude_flag_binding`.
Also keep all encountered bindings in `resolve_ident_in_scope_set`, it allows to get rid of `extern_prelude_item_binding`.
This also unblocks https://github.com/rust-lang/rust/pull/149681 because the newly preserved data will help to fix the regressions in https://github.com/rust-lang/rust/pull/149681#issuecomment-3679059703 in a reasonable way.
parser/lexer: bump to Unicode 17, use faster unicode-ident
Hello,
Bump the unicode version used by lexer/parser to 17.0.0 by updating:
- `unicode-normalization` to 0.1.25
- `unicode-properties` to 0.1.4
- `unicode-width` to 0.2.2
and by replacing `unicode-xid` with `unicode-ident` which is also 6 times faster.
I think it might be worth to run the benchmarks to double check.
(`unicode-ident` is already in `src/tools/tidy/src/deps.rs`)
Thanks!
Overhaul filename handling for cross-compiler consistency
This PR overhauls the way we handle filenames in the compiler and `rmeta` in order to achieve achieve cross-compiler consistency (ie. having the same path no matter if the filename was created in the current compiler session or is coming from `rmeta`).
This is required as some parts of the compiler rely on consistent paths for the soundness of generated code (see rust-lang/rust#148328).
In order to achieved consistency multiple steps are being taken by this PR:
- by making `RealFileName` immutable
- by only having `SourceMap::to_real_filename` create `RealFileName`
- currently `RealFileName` can be created from any `Path` and are remapped afterwards, which creates consistency issue
- by also making `RealFileName` holds it's working directory, embeddable name and the remapped scopes
- this removes the need for a `Session`, to know the current(!) scopes and cwd, which is invalid as they may not be equal to the scopes used when creating the filename
In order for `SourceMap::to_real_filename` to know which scopes to apply `FilePathMapping` now takes the current remapping scopes to apply, which makes `FileNameDisplayPreference` and company useless and are removed.
This PR is split-up in multiple commits (unfortunately not atomic), but should help review the changes.
Unblocks https://github.com/rust-lang/rust/pull/147611
Fixes https://github.com/rust-lang/rust/issues/148328
This commit refactors `SourceMap` and most importantly `RealFileName` to
make it self-contained in order to achieve cross-compiler consistency.
This is achieved:
- by making `RealFileName` immutable
- by only having `SourceMap::to_real_filename` create `RealFileName`
- by also making `RealFileName` holds it's working directory,
it's embeddable name and the remapped scopes
- by making most `FileName` and `RealFileName` methods take a scope as
an argument
In order for `SourceMap::to_real_filename` to know which scopes to apply
`FilePathMapping` now takes the current remapping scopes to apply, which
makes `FileNameDisplayPreference` and company useless and are removed.
The scopes type `RemapPathScopeComponents` was moved from
`rustc_session::config` to `rustc_span`.
The previous system for scoping the local/remapped filenames
`RemapFileNameExt::for_scope` is no longer useful as it's replaced by
methods on `FileName` and `RealFileName`.
This allows LTO to work when compiling jemalloc, which should yield a
small performance boost, and makes miri's behaviour here match clippy
and rustdoc.
feat: Enable annotate-snippets' simd feature
`annotate-snippets` `simd` feature enables the use of `memchr` when searching for `char`/`str`. This should hopefully improve performance when [`annotate-snippets` is passed large `source`](https://github.com/rust-lang/rust/pull/148188#issuecomment-3550280300).
Bump compiler dependencies
https://github.com/rust-lang/rust/pull/145849#issuecomment-3394832713
This manually downgrades the `wasip`/`wit-bindgen`/`getrandom` deps to avoid pulling in a binary blob, but it would be good to pin this automatically in a way which doesn't cause these blobs to be pulled in.
rustdoc-json: add rlib path to ExternalCrate to enable robust crate resolution
Historically, it's not been possible to robustly resolve a cross-crate item in rustdoc-json. If you had a `Id` that wasn't in `Crate::index` (because it was defined in a different crate), you could only look it up it `Crate::paths`. But there, you don't get the full information, only an `ItemSummary`. This tells you the `path` and the `crate_id`.
But knowing the `crate_id` isn't enough to be able to build/find the rustdoc-json output with this item. It's only use is to get a `ExternalCrate` (via `Crate::external_crates`). But that only tells you the `name` (as a string). This isn't enough to uniquely identify a crate, as there could be multiple versions/features [^1] [^2].
This was originally proposed to be solved via `@LukeMathWalker's` `--orchestrator-id` proposal (https://github.com/rust-lang/compiler-team/issues/635). But that requires invasive changes to cargo/rustc. This PR instead implements `@Urgau's` proposal to re-use the path to a crate's rmeta/rlib as a unique identifer. Callers can use that to determine which package it corresponds to in the language of the build-system above rustc. E.g. for cargo, `cargo rustdoc --message-format=json --output-format=json -Zunstable-options`).
(Once you've found the right external crate's rustdoc-json output, you still need to resolve the path->id in that crate. But that's """just""" a matter of walking the module tree. We should probably still make that nicer (by, for example, allowing sharing `Id`s between rustdoc-json document), but that's a future concern)
For some notes from RustWeek 2025, where this was designed, see https://hackmd.io/0jkdguobTnW7nXoGKAxfEQ
CC `@obi1kenobi` (who wants this for cargo-semver-checks [^3]), `@epage` (who's conversations on what and wasn't possible with cargo informed taking this approach to solve this problem)
r? `@GuillaumeGomez`
## TODO:
- [x] Docs: [Done](e4cdd0c24a..457ed4edb1)
- [x] Tests: [Done](2e1b954dc5..4d00c1a7ee)
[^1]: https://github.com/rust-lang/compiler-team/issues/635#issue-1714254865 § Problem
[^2]: https://rust-lang.zulipchat.com/#narrow/channel/266220-t-rustdoc/topic/Identifying.20external.20crates.20in.20Rustdoc.20JSON/with/352701211
[^3]: https://github.com/obi1kenobi/cargo-semver-checks/issues/638
