Rollup of 9 pull requests
Successful merges:
- #93969 (Only add codegen backend to dep info if -Zbinary-dep-depinfo is used)
- #94605 (Add missing links in platform support docs)
- #95372 (make unaligned_references lint deny-by-default)
- #95859 (Improve diagnostics for unterminated nested block comment)
- #95961 (implement SIMD gather/scatter via vector getelementptr)
- #96004 (Consider lifetimes when comparing types for equality in MIR validator)
- #96050 (Remove some now-dead code that was only relevant before deaggregation.)
- #96070 ([test] Add test cases for untested functions for BTreeMap)
- #96099 (MaybeUninit array cleanup)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Better method call error messages
Rebase/continuation of #71827
~Based on #92360~
~Based on #93118~
There's a decent description in #71827 that I won't copy here (for now at least)
In addition to rebasing, I've tried to restore most of the original suggestions for invalid arguments. Unfortunately, this does make some of the errors a bit verbose. To fix this will require a bit of refactoring to some of the generalized error suggestion functions, and I just don't have the time to go into it right now.
I think this is in a state that the error messages are overall better than before without a reduction in the suggestions given.
~I've tried to split out some of the easier and self-contained changes into separate commits (mostly in #92360, but also one here). There might be more than can be done here, but again just lacking time.~
r? `@estebank` as the original reviewer of #71827
This attempts to bring better error messages to invalid method calls, by applying some heuristics to identify common mistakes.
The algorithm is inspired by Levenshtein distance and longest common sub-sequence. In essence, we treat the types of the function, and the types of the arguments you provided as two "words" and compute the edits to get from one to the other.
We then modify that algorithm to detect 4 cases:
- A function input is missing
- An extra argument was provided
- The type of an argument is straight up invalid
- Two arguments have been swapped
- A subset of the arguments have been shuffled
(We detect the last two as separate cases so that we can detect two swaps, instead of 4 parameters permuted.)
It helps to understand this argument by paying special attention to terminology: "inputs" refers to the inputs being *expected* by the function, and "arguments" refers to what has been provided at the call site.
The basic sketch of the algorithm is as follows:
- Construct a boolean grid, with a row for each argument, and a column for each input. The cell [i, j] is true if the i'th argument could satisfy the j'th input.
- If we find an argument that could satisfy no inputs, provided for an input that can't be satisfied by any other argument, we consider this an "invalid type".
- Extra arguments are those that can't satisfy any input, provided for an input that *could* be satisfied by another argument.
- Missing inputs are inputs that can't be satisfied by any argument, where the provided argument could satisfy another input
- Swapped / Permuted arguments are identified with a cycle detection algorithm.
As each issue is found, we remove the relevant inputs / arguments and check for more issues. If we find no issues, we match up any "valid" arguments, and start again.
Note that there's a lot of extra complexity:
- We try to stay efficient on the happy path, only computing the diagonal until we find a problem, and then filling in the rest of the matrix.
- Closure arguments are wrapped in a tuple and need to be unwrapped
- We need to resolve closure types after the rest, to allow the most specific type constraints
- We need to handle imported C functions that might be variadic in their inputs.
I tried to document a lot of this in comments in the code and keep the naming clear.
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. :)
Improve diagnostics for unterminated nested block comment
close#95283
(This is my first time try to messing around with rust compiler and might get a lot of things wrong... 🙇 )
make unaligned_references lint deny-by-default
This lint has been warn-by-default for a year now (since https://github.com/rust-lang/rust/pull/82525), so I think it is time to crank it up a bit. Code that triggers the lint causes UB (without `unsafe`) when executed, so we really don't want people to write code like this.
Only add codegen backend to dep info if -Zbinary-dep-depinfo is used
I am currently migrating the cg_clif build system from using a binary linked to the codegen backend as rustc replacement to passing `-Zcodegen-backend` instead. Without this PR this would force cargo to rebuild the sysroot on any change to the codegen backend even if I explicitly specify that I want it to be preserved, which would make development of cg_clif a lot slower. If you still want to have changes to the codegen backend invalidate the cargo build cache you can explicitly specify `-Zbinary-dep-depinfo`.
cc ``@eddyb`` as the codegen backend was initially added to the depinfo for rust-gpu.
Implement sym operands for global_asm!
Tracking issue: #93333
This PR is pretty much a complete rewrite of `sym` operand support for inline assembly so that the same implementation can be shared by `asm!` and `global_asm!`. The main changes are:
- At the AST level, `sym` is represented as a special `InlineAsmSym` AST node containing a path instead of an `Expr`.
- At the HIR level, `sym` is split into `SymStatic` and `SymFn` depending on whether the path resolves to a static during AST lowering (defaults to `SynFn` if `get_early_res` fails).
- `SymFn` is just an `AnonConst`. It runs through typeck and we just collect the resulting type at the end. An error is emitted if the type is not a `FnDef`.
- `SymStatic` directly holds a path and the `DefId` of the `static` that it is pointing to.
- The representation at the MIR level is mostly unchanged. There is a minor change to THIR where `SymFn` is a constant instead of an expression.
- At the codegen level we need to apply the target's symbol mangling to the result of `tcx.symbol_name()` depending on the target. This is done by calling the LLVM name mangler, which handles all of the details.
- On Mach-O, all symbols have a leading underscore.
- On x86 Windows, different mangling is used for cdecl, stdcall, fastcall and vectorcall.
- No mangling is needed on other platforms.
r? `@nagisa`
cc `@eddyb`
docs: Update tests chapter for Termination stabilization
A small update for the docs of `#[test]` functions as a result of the `Termination` stabilization in #93840.
only downgrade selection Error -> Ambiguous if type error is in predicate
That is, we don't care if there's a TypeError type in the ParamEnv.
Fixes#95408
remove find_use_placement
A more robust solution to finding where to place use suggestions was added in #94584.
The algorithm uses the AST to find the span for the suggestion so we pass this span
down to the HIR during lowering and use it instead of calling `find_use_placement`
Fixes#94941
Check var scope if it exist
Fixes#92893.
Added helper function to check the scope of a variable, if it doesn't have a scope call delay_span_bug, which avoids us trying to get a block/scope that doesn't exist.
Had to increase `ROOT_ENTRY_LIMIT` was getting tidy error
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.
Stabilize `derive_default_enum`
This stabilizes `#![feature(derive_default_enum)]`, as proposed in [RFC 3107](https://github.com/rust-lang/rfcs/pull/3107) and tracked in #87517. In short, it permits you to `#[derive(Default)]` on `enum`s, indicating what the default should be by placing a `#[default]` attribute on the desired variant (which must be a unit variant in the interest of forward compatibility).
```````@rustbot``````` label +S-waiting-on-review +T-lang
Rustdoc doesn't require the build artifacts to generate the docs, and
especially in the case of rustc, it greatly increases the time needed to
run the build.
- Statically ensure that only the top_stage of a tool is documented
If another part of rustbuild tried to document a different stage, it
would run into errors because `check::Rustc` unconditionally uses the
top stage.
- Try building rustc instead of checking to avoid duplicate artifacts
Tries to workaround the following error:
```
error[E0464]: multiple matching crates for `rustc_ast`
--> src/librustdoc/lib.rs:40:1
|
40 | extern crate rustc_ast;
| ^^^^^^^^^^^^^^^^^^^^^^^
|
= note: candidates:
crate `rustc_ast`: /checkout/obj/build/x86_64-unknown-linux-gnu/stage2/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_ast-6d7c193782263d89.rlib
crate `rustc_ast`: /checkout/obj/build/x86_64-unknown-linux-gnu/stage2/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_ast-e5d09eda5beb759c.rmeta
```
when checking pointee metadata, canonicalize the `Sized` check
Use `infcx.predicate_must_hold_modulo_regions` with a `Sized` obligation instead of just calling `ty.is_sized`, because the latter does not canonicalize region and type vars (and in the test case I added in this PR, there's a region var in the `ParamEnv`).
Fixes#95311
errors: lazily load fallback fluent bundle
Addresses (hopefully) https://github.com/rust-lang/rust/pull/95667#issuecomment-1094794087.
Loading the fallback bundle in compilation sessions that won't go on to emit any errors unnecessarily degrades compile time performance, so lazily create the Fluent bundle when it is first required.
r? `@ghost` (just for perf initially)
fix: wrong trait import suggestion for T:
The suggestion to bound `T` had an extra `:`.
```rust
fn foo<T:>(t: T) {
t.clone();
}
```
```
error[E0599]: no method named `clone` found for type parameter `T` in the current scope
--> src/lib.rs:2:7
|
2 | t.clone();
| ^^^^^ method not found in `T`
|
= help: items from traits can only be used if the type parameter is bounded by the trait
help: the following trait defines an item `clone`, perhaps you need to restrict type parameter `T` with it:
|
1 | fn foo<T: Clone:>(t: T) {
| ~~~~~~~~
```
Fixes: #95898
Improve Rustdoc UI for scraped examples with multiline arguments, fix overflow in line numbers
This PR improves a few aspects of the scrape examples feature in Rustdoc.
* Only function names and not the full call expression are highlighted.
* For call-sites with multiline arguments, the minimized code viewer will scroll to the top of the call-site rather than the middle if the argument is larger than the viewer size, ensuring that the function name is visible.
* This fixes an issue where the line numbers column had a visible x-scroll bar.
r? `@GuillaumeGomez`
Use mir constant in thir instead of ty::Const
This is blocked on https://github.com/rust-lang/rust/pull/94059 (does include its changes, the first two commits in this PR correspond to those changes) and https://github.com/rust-lang/rust/pull/93800 being reinstated (which had to be reverted). Mainly opening since `@lcnr` offered to give some feedback and maybe also for a perf-run (if necessary).
This currently contains a lot of duplication since some of the logic of `ty::Const` had to be copied to `mir::ConstantKind`, but with the introduction of valtrees a lot of that functionality will disappear from `ty::Const`.
Only the last commit contains changes that need to be reviewed here. Did leave some `FIXME` comments regarding future implementation decisions and some things that might be incorrectly implemented.
r? `@oli-obk`
Fix broken link in coverage tools docs
During stabilization the link to example screenshot wad not updated, making rendered docs somewhat less useful. Move that screenshot from unstable book into rustc docs and make documentation point to that new place. Also remove `/img` in unstable book since there are no more any files there.
Always use system `python3` on MacOS
This PR includes 2 changes:
1. Always use the system Python found at `/usr/bin/python3` on MacOS
2. Removes the hard requirement on having `python` in your system path if you didn't specify alternatives. The proposed change will instead attempt to find and use in order: `python` -> `python3` -> `python2`. This change isn't strictly necessary but without any change to this check, the original issue inspiring this change will still exist.
Fixes#95204
r? ```@jyn514```
Loading the fallback bundle in compilation sessions that won't go on to
emit any errors unnecessarily degrades compile time performance, so
lazily create the Fluent bundle when it is first required.
Signed-off-by: David Wood <david.wood@huawei.com>
Rollup of 7 pull requests
Successful merges:
- #95316 (Rustdoc: Discriminate required and provided associated constants and types)
- #95405 (Move name resolution logic to a dedicated file)
- #95914 (Implement tuples using recursion)
- #95918 (Delay a bug when we see SelfCtor in ref pattern)
- #95970 (Fix suggestions in case of `T:` bounds)
- #95973 (prevent opaque types from appearing in impl headers)
- #95986 (Autolabel library PRs with T-libs)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
prevent opaque types from appearing in impl headers
cc `@lqd`
opaque types are not distinguishable from their hidden type at the codegen stage. So we could either end up with cases where the hidden type doesn't implement the trait (which will thus ICE) or where the hidden type does implement the trait (so we'd be using its impl instead of the one written for the opaque type). This can even lead to unsound behaviour without unsafe code.
Fixes https://github.com/rust-lang/rust/issues/86411.
Fixes https://github.com/rust-lang/rust/issues/84660.
rebase of #87382 plus some diagnostic tweaks
Fix suggestions in case of `T:` bounds
This PR fixes a corner case in `suggest_constraining_type_params` that was causing incorrect suggestions.
For the following functions:
```rust
fn a<T:>(t: T) { [t, t]; }
fn b<T>(t: T) where T: { [t, t]; }
```
We previously suggested the following:
```text
...
help: consider restricting type parameter `T`
|
1 | fn a<T: Copy:>(t: T) { [t, t]; }
| ++++++
...
help: consider further restricting this bound
|
2 | fn b<T>(t: T) where T: + Copy { [t, t]; }
| ++++++
```
Note that neither `T: Copy:` not `where T: + Copy` is a correct bound.
With this commit the suggestions are correct:
```text
...
help: consider restricting type parameter `T`
|
1 | fn a<T: Copy>(t: T) { [t, t]; }
| ++++
...
help: consider further restricting this bound
|
2 | fn b<T>(t: T) where T: Copy { [t, t]; }
| ++++
```
r? `@compiler-errors`
I've tried fixing #95898 here too, but got too confused with how `suggest_traits_to_import` works and what it does 😅
