Emit the enum discriminant separately for the Encodable macro
This changes the `Encodable` proc macro to first emit the discriminant with a separate `match` statement, then emit the fields. LLVM can optimize down the first `match` to just a read of the enum discriminant. This avoids generating a `emit_usize` call per variant and enums with no fields now optimize down to just a single `emit_usize` call.
The no variant case is special cased to avoid warnings about unreachable code.
<table><tr><td rowspan="2">Benchmark</td><td colspan="1"><b>Before</b></th><td colspan="2"><b>After</b></th></tr><tr><td align="right">Time</td><td align="right">Time</td><td align="right">%</th></tr><tr><td>🟣 <b>clap</b>:check:unchanged</td><td align="right">0.4676s</td><td align="right">0.4640s</td><td align="right"> -0.78%</td></tr><tr><td>🟣 <b>hyper</b>:check:unchanged</td><td align="right">0.1348s</td><td align="right">0.1338s</td><td align="right"> -0.75%</td></tr><tr><td>🟣 <b>regex</b>:check:unchanged</td><td align="right">0.3370s</td><td align="right">0.3352s</td><td align="right"> -0.54%</td></tr><tr><td>🟣 <b>syn</b>:check:unchanged</td><td align="right">0.6326s</td><td align="right">0.6281s</td><td align="right"> -0.71%</td></tr><tr><td>🟣 <b>syntex_syntax</b>:check:unchanged</td><td align="right">1.8561s</td><td align="right">1.8589s</td><td align="right"> 0.15%</td></tr><tr><td>Total</td><td align="right">3.4282s</td><td align="right">3.4200s</td><td align="right"> -0.24%</td></tr><tr><td>Summary</td><td align="right">1.0000s</td><td align="right">0.9947s</td><td align="right"> -0.53%</td></tr></table>
Upgrade to ena-0.14.1.
It avoids some inlining within its `inlined_probe_value` function, which seems to result in better codegen for the very large `process_obligations` function within rustc. It might also help with reducing the bimodal perf results we see for the `keccak` and `cranelift-codegen-0.82.1` benchmarks.
r? `@ghost`
Remove `from` lang item
It was probably a leftover from the old `?` desugaring but anyways, it's unused now except for clippy, which can just use a diagnostics item.
statically guarantee that current error codes are documented
Closes#61137 (that's right!)
Pretty simple refactor (often just a change from `Result<Option<&str>>` to `Result<&str>`)
r? `@GuillaumeGomez` (could you specially look at 53044158eff0d64673a6100f701c57b484232aca? I believe you wrote that in the first place, just want to make sure you're happy with the change)
Fix `VecDeque::shrink_to` and add tests.
Fixes#108453.
Also adds both a specific test with the code from #108453 and an exhaustive test that checks all possible head positions, lengths and target capacities for deques with capacity 16.
cc `@trinity-1686a` `@scottmcm`
rustc_infer: Consolidate obligation elaboration de-duplication
# Explanation
The obligations `Elaborator` is doing de-duplication of obligations in 3 different locations. 1 off which has a comment.
This PR consolidates the functionality and comment to a single function.
Replace parse_[sth]_expr with parse_expr_[sth] function names
This resolves an inconsistency in naming style for functions on the parser, where:
* functions parsing specific kinds of items are named `parse_item_[sth]` and
* functions parsing specific kinds of *expressions* are named `parse_[sth]_expr`
favoring the style used by functions for items. There are multiple advantages of that style:
* functions of both categories are collected in the same place in the [rustdoc output](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_parse/parser/struct.Parser.html).
* it helps with autocompletion, as you can narrow down your search for a function to those about expressions.
* it mirrors rust's path syntax where less specific things come first, then it gets more specific, i.e. `std::collections::hash_map::Entry`.
The disadvantage is that it doesn't "read like a sentence" any more. But I think the advantages weigh more greatly.
This change was mostly application of this command:
```
sed -i -E 's/(fn |\.)parse_([[:alnum:]_]+)_expr/\1parse_expr_\2/' compiler/rustc_parse/src/parser/*.rs
```
Plus very minor fixes outside of `rustc_parse`, and an invocation of `x fmt`.
Add `ErrorGuaranteed` to `hir::{Expr,Ty}Kind::Err` variants
First step in making the `Err` variants of `ExprKind` and `TyKind` require an `ErrorGuaranteed` during parsing. Making the corresponding AST versions require `ErrorGuaranteed` is a bit harder, whereas it was pretty easy to do this for HIR, so let's do that first.
The only weird thing about this PR is that `ErrorGuaranteed` is moved to `rustc_span`. This is *certainly* not the right place to put it, but `rustc_hir` cannot depend on `rustc_error` because the latter already depends on the former. Should I just pull out some of the error machinery from `rustc_error` into an even more minimal crate that `rustc_hir` can depend on? Advice would be appreciated.
Require `literal`s for some `(u)int_impl!` parameters
The point of these is to be seen *lexically* in the docs, so they should always be passed as the correct literal, not as an expression.
(Otherwise we could just compute `Min`/`Max` from `BITS`, for example.)
r? Nilstrieb
Treat `str` as containing `[u8]` for auto trait purposes
Wanted to gauge ``@rust-lang/lang`` and ``@rust-lang/types`` teams' thoughts on treating `str` as "containing" a `[u8]` slice for auto-trait purposes.
``@dtolnay`` brought this up in https://github.com/rust-lang/rust/issues/13231#issuecomment-1399386472 as a blocker for future `str` type librarification, and I think it's both a valid concern and very easy to fix. I'm interested in actually doing that `str` type librarification (#107939), but this probably should be considered in the mean time regardless of that PR.
r? types for the impl, though this definitely needs an FCP.
This adds both a test specific to #108453 as well as an exhaustive test
that goes through all possible combinations of head index, length and target capacity
for a deque with capacity 16.
Rollup of 8 pull requests
Successful merges:
- #107062 (Do some cleanup of doc/index.md)
- #107890 (Lint against `Iterator::map` receiving a callable that returns `()`)
- #108431 (Add regression test for #107918)
- #108432 (test: drop unused deps)
- #108436 (make "proc macro panicked" translatable)
- #108444 (docs/test: add UI test and docs for `E0476`)
- #108449 (Do not lint ineffective unstable trait impl for unresolved trait)
- #108456 (Complete migrating `ast_passes` to derive diagnostics)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
docs/test: add UI test and docs for `E0476`
Final undocumented error code. Not entirely sure about wording in the docs.
Part of https://github.com/rust-lang/rust/issues/61137.
r? ```@compiler-errors```
cc ```@compiler-errors```
Do some cleanup of doc/index.md
I think a lot of people get to this landing page from `rustup doc`, and it's a bit tricky to find some useful information. I attempted to clean it up here a bit, from the commit message:
- Add quick link to API docs
- Add marker for external links, to help offline users
- Add information about using 'cargo doc' and the playground
- Clean up some of the wording
- Update body & header style to match rustdoc defaults
- Bump heading levels so main page header is 1, others are 2 (all were level 1 before)
Do not panic when analyzing the malformed origin of a format string
Fixes#10148. This will trigger only when generating format strings while accepting weird things in a procedural macro and setting the span to something which is not a string.
changelog: none
Split `x setup` sub-actions to CLI arguments
Closes#107846
This adds a new `none` profile option which simply skips the `config.toml` step. It also adds `hook` and `vscode` subcommands, for installing the pre-push hook and getting `settings.json` respectively.
Implement -Zlink-directives=yes/no
`-Zlink-directives=no` will ignored `#[link]` directives while compiling a crate, so nothing is emitted into the crate's metadata. The assumption is that the build system already knows about the crate's native dependencies and can provide them at link time without these directives.
This is another way to address issue # #70093, which is currently addressed by `-Zlink-native-libraries` (implemented in #70095). The latter is implemented at link time, which has the effect of ignoring `#[link]` in *every* crate. This makes it a very large hammer as it requires all native dependencies to be known to the build system to be at all usable, including those in sysroot libraries. I think this means its effectively unused, and definitely under-used.
Being able to control this on a crate-by-crate basis should make it much easier to apply when needed.
I'm not sure if we need both mechanisms, but we can decide that later.
cc `@pcwalton` `@cramertj`
[breaking change] Remove a rustdoc back compat warning
This warning was introduced in https://github.com/rust-lang/rust/pull/62855 for users who use `rustdoc` directly on proc macro crates (instead of using `cargo doc`) without passing `--crate-type proc-macro` (which `cargo doc` passed automatically).
Benoît du Garreau