Implement `for<>` lifetime binder for closures
This PR implements RFC 3216 ([TI](https://github.com/rust-lang/rust/issues/97362)) and allows code like the following:
```rust
let _f = for<'a, 'b> |a: &'a A, b: &'b B| -> &'b C { b.c(a) };
// ^^^^^^^^^^^--- new!
```
cc ``@Aaron1011`` ``@cjgillot``
Always create elided lifetime parameters for functions
Anonymous and elided lifetimes in functions are sometimes (async fns) --and sometimes not (regular fns)-- desugared to implicit generic parameters.
This difference of treatment makes it some downstream analyses more complicated to handle. This step is a pre-requisite to perform lifetime elision resolution on AST.
There is currently an inconsistency in the treatment of argument-position impl-trait for functions and async fns:
```rust
trait Foo<'a> {}
fn foo(t: impl Foo<'_>) {} //~ ERROR missing lifetime specifier
async fn async_foo(t: impl Foo<'_>) {} //~ OK
fn bar(t: impl Iterator<Item = &'_ u8>) {} //~ ERROR missing lifetime specifier
async fn async_bar(t: impl Iterator<Item = &'_ u8>) {} //~ OK
```
The current implementation reports "missing lifetime specifier" on `foo`, but **accepts it** in `async_foo`.
This PR **proposes to accept** the anonymous lifetime in both cases as an extra generic lifetime parameter.
This change would be insta-stable, so let's ping t-lang.
Anonymous lifetimes in GAT bindings keep being forbidden:
```rust
fn foo(t: impl Foo<Assoc<'_> = Bar<'_>>) {}
^^ ^^
forbidden ok
```
I started a discussion here: https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/Anonymous.20lifetimes.20in.20universal.20impl-trait/near/284968606
r? ``@petrochenkov``
Use less string interning
This removes string interning in a couple of places where doing so won't result in perf improvements. I also switched one place to use pre-interned symbols.
This commit adds new methods that combine sequences of existing
formatting methods.
- `Formatter::debug_{tuple,struct}_field[12345]_finish`, equivalent to a
`Formatter::debug_{tuple,struct}` + N x `Debug{Tuple,Struct}::field` +
`Debug{Tuple,Struct}::finish` call sequence.
- `Formatter::debug_{tuple,struct}_fields_finish` is similar, but can
handle any number of fields by using arrays.
These new methods are all marked as `doc(hidden)` and unstable. They are
intended for the compiler's own use.
Special-casing up to 5 fields gives significantly better performance
results than always using arrays (as was tried in #95637).
The commit also changes the `Debug` deriving code to use these new methods. For
example, where the old `Debug` code for a struct with two fields would be like
this:
```
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
match *self {
Self {
f1: ref __self_0_0,
f2: ref __self_0_1,
} => {
let debug_trait_builder = &mut ::core::fmt::Formatter::debug_struct(f, "S2");
let _ = ::core::fmt::DebugStruct::field(debug_trait_builder, "f1", &&(*__self_0_0));
let _ = ::core::fmt::DebugStruct::field(debug_trait_builder, "f2", &&(*__self_0_1));
::core::fmt::DebugStruct::finish(debug_trait_builder)
}
}
}
```
the new code is like this:
```
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
match *self {
Self {
f1: ref __self_0_0,
f2: ref __self_0_1,
} => ::core::fmt::Formatter::debug_struct_field2_finish(
f,
"S2",
"f1",
&&(*__self_0_0),
"f2",
&&(*__self_0_1),
),
}
}
```
This shrinks the code produced for `Debug` instances
considerably, reducing compile times and binary sizes.
Co-authored-by: Scott McMurray <scottmcm@users.noreply.github.com>
Mention formatting macros when encountering `ArgumentV1` method in const
Also open to just closing this if it's overkill. There are a lot of other distracting error messages around, so maybe it's not worth fixing just this one.
Fixes#93665
[RFC 2011] Minimal initial implementation
Tracking issue: #44838
Third step of #96496
Implementation has ~290 LOC with the bare minimum to be in a functional state. Currently only searches for binary operations to mimic what `assert_eq!` and `assert_ne!` already do.
r? `@oli-obk`
Introduce allow-by-default lints for checking whether diagnostics are
written in `SessionDiagnostic`/`AddSubdiagnostic` impls and whether
diagnostics are translatable. These lints can be denied for modules once
they are fully migrated to impls and translation.
Signed-off-by: David Wood <david.wood@huawei.com>
This commit adds a new unstable attribute, `#[doc(tuple_varadic)]`, that
shows a 1-tuple as `(T, ...)` instead of just `(T,)`, and links to a section
in the tuple primitive docs that talks about these.
There are two impls of the `Encoder` trait: `opaque::Encoder` and
`opaque::FileEncoder`. The former encodes into memory and is infallible, the
latter writes to file and is fallible.
Currently, standard `Result`/`?`/`unwrap` error handling is used, but this is a
bit verbose and has non-trivial cost, which is annoying given how rare failures
are (especially in the infallible `opaque::Encoder` case).
This commit changes how `Encoder` fallibility is handled. All the `emit_*`
methods are now infallible. `opaque::Encoder` requires no great changes for
this. `opaque::FileEncoder` now implements a delayed error handling strategy.
If a failure occurs, it records this via the `res` field, and all subsequent
encoding operations are skipped if `res` indicates an error has occurred. Once
encoding is complete, the new `finish` method is called, which returns a
`Result`. In other words, there is now a single `Result`-producing method
instead of many of them.
This has very little effect on how any file errors are reported if
`opaque::FileEncoder` has any failures.
Much of this commit is boring mechanical changes, removing `Result` return
values and `?` or `unwrap` from expressions. The more interesting parts are as
follows.
- serialize.rs: The `Encoder` trait gains an `Ok` associated type. The
`into_inner` method is changed into `finish`, which returns
`Result<Vec<u8>, !>`.
- opaque.rs: The `FileEncoder` adopts the delayed error handling
strategy. Its `Ok` type is a `usize`, returning the number of bytes
written, replacing previous uses of `FileEncoder::position`.
- Various methods that take an encoder now consume it, rather than being
passed a mutable reference, e.g. `serialize_query_result_cache`.
Add support for emitting functions with `coldcc` to LLVM
The eventual goal is to try using this for things like the internal panicking stuff, to see whether it helps.
Using diagnostic items avoids having to update the paths if the guard
types ever get moved around for some reason. Additionally, it also greatly
simplifies the `is_sync_lock` check.
This commit adds an alternative content boxing syntax,
and uses it inside alloc.
The usage inside the very performance relevant code in
liballoc is the only remaining relevant usage of box syntax
in the compiler (outside of tests, which are comparatively
easy to port).
box syntax was originally designed to be used by all Rust
developers. This introduces a replacement syntax more tailored
to only being used inside the Rust compiler, and with it,
lays the groundwork for eventually removing box syntax.
Replace `#[default_method_body_is_const]` with `#[const_trait]`
pulled out of #96077
related issues: #67792 and #92158
cc `@fee1-dead`
This is groundwork to only allowing `impl const Trait` for traits that are marked with `#[const_trait]`. This is necessary to prevent adding a new default method from becoming a breaking change (as it could be a non-const fn).
Add support for embedding pretty printers via `#[debugger_visualizer]` attribute
Initial support for [RFC 3191](https://github.com/rust-lang/rfcs/pull/3191) in PR https://github.com/rust-lang/rust/pull/91779 was scoped to supporting embedding NatVis files using a new attribute. This PR implements the pretty printer support as stated in the RFC mentioned above.
This change includes embedding pretty printers in the `.debug_gdb_scripts` just as the pretty printers for rustc are embedded today. Also added additional tests for embedded pretty printers. Additionally cleaned up error checking so all error checking is done up front regardless of the current target.
RFC: https://github.com/rust-lang/rfcs/pull/3191
Ensure all error checking for `#[debugger_visualizer]` is done up front and not when the `debugger_visualizer` query is run.
Clean up potential ODR violations when embedding pretty printers into the `__rustc_debug_gdb_scripts_section__` section.
Respond to PR comments and update documentation.
Like we have `add`/`sub` which are the `usize` version of `offset`, this adds the `usize` equivalent of `offset_from`. Like how `.add(d)` replaced a whole bunch of `.offset(d as isize)`, you can see from the changes here that it's fairly common that code actually knows the order between the pointers and *wants* a `usize`, not an `isize`.
As a bonus, this can do `sub nuw`+`udiv exact`, rather than `sub`+`sdiv exact`, which can be optimized slightly better because it doesn't have to worry about negatives. That's why the slice iterators weren't using `offset_from`, though I haven't updated that code in this PR because slices are so perf-critical that I'll do it as its own change.
This is an intrinsic, like `offset_from`, so that it can eventually be allowed in CTFE. It also allows checking the extra safety condition -- see the test confirming that CTFE catches it if you pass the pointers in the wrong order.
Cleanup `DebuggerVisualizerFile` type and other minor cleanup of queries.
Merge the queries for debugger visualizers into a single query.
Revert move of `resolve_path` to `rustc_builtin_macros`. Update dependencies in Cargo.toml for `rustc_passes`.
Respond to PR comments. Load visualizer files into opaque bytes `Vec<u8>`. Debugger visualizers for dynamically linked crates should not be embedded in the current crate.
Update the unstable book with the new feature. Add the tracking issue for the debugger_visualizer feature.
Respond to PR comments and minor cleanups.
Using an obviously-placeholder syntax. An RFC would still be needed before this could have any chance at stabilization, and it might be removed at any point.
But I'd really like to have it in nightly at least to ensure it works well with try_trait_v2, especially as we refactor the traits.
asm: Add a kreg0 register class on x86 which includes k0
Previously we only exposed a kreg register class which excludes the k0
register since it can't be used in many instructions. However k0 is a
valid register and we need to have a way of marking it as clobbered for
clobber_abi.
Fixes#94977
Previously we only exposed a kreg register class which excludes the k0
register since it can't be used in many instructions. However k0 is a
valid register and we need to have a way of marking it as clobbered for
clobber_abi.
Fixes#94977
implement SIMD gather/scatter via vector getelementptr
Fixes https://github.com/rust-lang/portable-simd/issues/271
However, I don't *really* know what I am doing here... Cc ``@workingjubilee`` ``@calebzulawski``
I didn't do anything for cranelift -- ``@bjorn3`` not sure if it's okay for that backend to temporarily break. I'm happy to cherry-pick a patch that adds cranelift support. :)
Create (unstable) 2024 edition
[On Zulip](https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/Deprecating.20macro.20scoping.20shenanigans/near/272860652), there was a small aside regarding creating the 2024 edition now as opposed to later. There was a reasonable amount of support and no stated opposition.
This change creates the 2024 edition in the compiler and creates a prelude for the 2024 edition. There is no current difference between the 2021 and 2024 editions. Cargo and other tools will need to be updated separately, as it's not in the same repository. This change permits the vast majority of work towards the next edition to proceed _now_ instead of waiting until 2024.
For sanity purposes, I've merged the "hello" UI tests into a single file with multiple revisions. Otherwise we'd end up with a file per edition, despite them being essentially identical.
````@rustbot```` label +T-lang +S-waiting-on-review
Not sure on the relevant team, to be honest.
* split `fuzzy_provenance_casts` into a ptr2int and a int2ptr lint
* feature gate both lints
* update documentation to be more realistic short term
* add tests for these lints
When encountering an unsatisfied trait bound, if there are no other
suggestions, mention all the types that *do* implement that trait:
```
error[E0277]: the trait bound `f32: Foo` is not satisfied
--> $DIR/impl_wf.rs:22:6
|
LL | impl Baz<f32> for f32 { }
| ^^^^^^^^ the trait `Foo` is not implemented for `f32`
|
= help: the following other types implement trait `Foo`:
Option<T>
i32
str
note: required by a bound in `Baz`
--> $DIR/impl_wf.rs:18:31
|
LL | trait Baz<U: ?Sized> where U: Foo { }
| ^^^ required by this bound in `Baz`
```
Mention implementers of traits in `ImplObligation`s.
Do not mention other `impl`s for closures, ranges and `?`.
