Same motivation as #136287, but for a newly introduced test. Rather than
over-constraining here, we just match the sret and accept pretty much
all other attributes.
@rustbot label llvm-main
r? @nikic
Rollup of 12 pull requests
Successful merges:
- #131651 (Create a generic AVR target: avr-none)
- #134340 (Stabilize `num_midpoint_signed` feature)
- #136473 (infer linker flavor by linker name if it's sufficiently specific)
- #136608 (Pass through of target features to llvm-bitcode-linker and handling them)
- #136985 (Do not ignore uninhabited types for function-call ABI purposes. (Remove BackendRepr::Uninhabited))
- #137270 (Fix `*-win7-windows-msvc` target since 26eeac1a1e)
- #137312 (Update references to cc_detect.rs)
- #137318 (Workaround Cranelift not yet properly supporting vectors smaller than 128bit)
- #137322 (Update docs for default features of wasm targets)
- #137324 (Make x86 QNX target name consistent with other Rust targets)
- #137338 (skip submodule updating logics on tarballs)
- #137340 (Add a notice about missing GCC sources into source tarballs)
r? `@ghost`
`@rustbot` modify labels: rollup
Add a notice about missing GCC sources into source tarballs
I didn't use `.gitkeep`, because that would be a hidden file that might not be noticed, whereas we want to let people inspecting the archive know why the sources are missing.
Inspired by https://github.com/rust-lang/rust/issues/137332.
r? `@onur-ozkan`
Make x86 QNX target name consistent with other Rust targets
Rename target to be consistent with other Rust targets: Use `i686` instead of `i586`
See also
- #136495
- #109173
CC: `@jonathanpallant` `@japaric` `@gh-tr` `@samkearney`
Update docs for default features of wasm targets
LLVM 20 enabled the `nontrapping-fptoint` and `bulk-memory` features by default, so this updates the corresponding documentation for the `wasm32-*` targets (which all point to `wasm32-unknown-unknown`).
Closes#137315 with a doc update for the doc part.
Workaround Cranelift not yet properly supporting vectors smaller than 128bit
While it would technically be possible to workaround this in cg_clif, it quickly becomes very messy and would likely cause correctness issues. Working around it in rustc instead is much simper and won't have any negative impact for code running on stable as vectors smaller than 128bit can only be made on nightly using core::simd or #[repr(simd)].
Update references to cc_detect.rs
The locations of these file references have since been changed.
This is a simple change to update the references to this `cc_detect.rs`
file.
Do not ignore uninhabited types for function-call ABI purposes. (Remove BackendRepr::Uninhabited)
Accepted MCP: https://github.com/rust-lang/compiler-team/issues/832Fixes#135802
Do not consider the inhabitedness of a type for function call ABI purposes.
* Remove the [`rustc_abi::BackendRepr::Uninhabited`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_abi/enum.BackendRepr.html) variant
* Instead calculate the `BackendRepr` of uninhabited types "normally" (as though they were not uninhabited "at the top level", but still considering inhabitedness of variants to determine enum layout, etc)
* Add an `uninhabited: bool` field to [`rustc_abi::LayoutData`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_abi/struct.LayoutData.html) so inhabitedness of a `LayoutData` can still be queried when necessary (e.g. when determining if an enum variant needs a tag value allocated to it).
This should not affect type layouts (size/align/field offset); this should only affect function call ABI, and only of uninhabited types.
cc ``@RalfJung``
Pass through of target features to llvm-bitcode-linker and handling them
When using the llvm-bitcode-linker (`linker-flavor=llbc`) target-features are not passed through and are not handled by it.
The llvm-bitcode-linker is mainly used as a self contained linker to link llvm bitcode for the nvptx64 target. It uses `llvm-link`, `opt` and `llc` internally. To produce a `.ptx` file of a specific ptx-version it is necessary to pass the version to llc with the `--mattr` option. Without explicitly setting it, the emitted `.ptx`-version is the minimum supported version of the `--target-cpu`.
I would like to be able to explicitly set the ptx version as [some llvm problems only occur in earlier `.ptx`-versions](https://github.com/llvm/llvm-project/issues/112998).
Therefore this pull request adds support for passing target features to llvm-bitcode-linker and handling them.
I was not quite sure if adding these features to `rustc_target/src/target_features.rs` is necessary or not. If so I will gladly add these.
r? ``@kjetilkjeka``
infer linker flavor by linker name if it's sufficiently specific
Fix: `rustc` does not infer `llvm-bitcode-linker` uses `llbc` linker flavor if targeting `nvptx64-nvidia-cuda`.
Stabilize `num_midpoint_signed` feature
This PR proposes that we stabilize the signed variants of [`iN::midpoint`](https://github.com/rust-lang/rust/issues/110840#issue-1684506201), the operation is equivalent to doing `(a + b) / 2` in a sufficiently large number.
The stabilized API surface would be:
```rust
/// Calculates the middle point of `self` and `rhs`.
///
/// `midpoint(a, b)` is `(a + b) / 2` as if it were performed in a
/// sufficiently-large signed integer type. This implies that the result is
/// always rounded towards zero and that no overflow will ever occur.
impl i{8,16,32,64,128,size} {
pub const fn midpoint(self, rhs: Self) -> Self;
}
```
T-libs-api previously stabilized the unsigned (and float) variants in #131784, the signed variants were left out because of the rounding that should be used in case of negative midpoint.
This stabilization proposal proposes that we round towards zero because:
- it makes the obvious `(a + b) / 2` in a sufficiently-large number always true
- using another rounding for the positive result would be inconsistent with the unsigned variants
- it makes `midpoint(-a, -b)` == `-midpoint(a, b)` always true
- it is consistent with `midpoint(a as f64, b as f64) as i64`
- it makes it possible to always suggest `midpoint` as a replacement for `(a + b) / 2` expressions *(which we may want to do as a future work given the 21.2k hits on [GitHub Search](https://github.com/search?q=lang%3Arust+%2F%5C%28%5Ba-zA-Z_%5D*+%5C%2B+%5Ba-zA-Z_%5D*%5C%29+%5C%2F+2%2F&type=code&p=1))*
`@scottmcm` mentioned a drawback in https://github.com/rust-lang/rust/pull/132191#issuecomment-2439891200:
> I'm torn, because rounding towards zero makes it "wider" than other values, which `>> 1` avoids -- `(a + b) >> 1` has the nice behaviour that `midpoint(a, b) + 2 == midpoint(a + 2, b + 2)`.
>
> But I guess overall sticking with `(a + b) / 2` makes sense as well, and I do like the negation property 🤷
Which I think is outweigh by the advantages cited above.
Closes#110840
cc `@rust-lang/libs-api`
cc `@scottmcm`
r? `@dtolnay`
Create a generic AVR target: avr-none
This commit removes the `avr-unknown-gnu-atmega328` target and replaces it with a more generic `avr-none` variant that must be specialized using `-C target-cpu` (e.g. `-C target-cpu=atmega328p`).
Seizing the day, I'm adding myself as the maintainer of this target - I've been already fixing the bugs anyway, might as well make it official 🙂
Related discussions:
- https://github.com/rust-lang/rust/pull/131171
- https://github.com/rust-lang/compiler-team/issues/800
try-job: x86_64-gnu-debug
Fix codegen of uninhabited PassMode::Indirect return types.
Add codegen test for uninhabited PassMode::Indirect return types.
Enable optimizations for uninhabited return type codegen test
LLVM 20 enabled the `nontrapping-fptoint` and `bulk-memory` features by
default, so this updates the corresponding documentation for the
`wasm32-*` targets (which all point to `wasm32-unknown-unknown`).
cc #137315
While it would technically be possible to workaround this in cg_clif, it
quickly becomes very messy and would likely cause correctness issues.
Working around it in rustc instead is much simper and won't have any
negative impact for code running on stable as vectors smaller than
128bit can only be made on nightly using core::simd or #[repr(simd)].
Don't store a redundant span in user-type projections
While experimenting with some larger changes, I noticed that storing this span here is unnecessary, because it is also present in the corresponding `CanonicalUserTypeAnnotation` and can be retrieved via the annotation's ID.
Emit `trunc nuw` for unchecked shifts and `to_immediate_scalar`
- For shifts this shrinks the IR by no longer needing an `assume` while still providing the UB information
- Having this on the `i8`→`i1` truncations will hopefully help with some places that have to load `i8`s or pass those in LLVM structs without range information
Bump sccache in CI to 0.9.1
We haven't updated the used sccache version for years, it has accrued a bunch of fixes and features in the meantime. It now supports the `--show-adv-stats` flag, which gives a more detailed summary of the results of caching. And it can also cache Rust code, which could be useful in the future (https://github.com/rust-lang/rust/pull/136942 - although now there are no large wins).
It also supports caching PGO now, but since the PGO profiles are always different, it won't make any real difference.
https://github.com/rust-lang/rust/pull/133076 previously tried to update the version to 0.3 (CC `@klensy)`
r? `@marcoieni`
Tweak "expected ident" parse error to avoid talking about doc comments
When encountering a doc comment without an identifier after, we'd unconditionally state "this doc comment doesn't document anything", swallowing the *actual* error which is that the thing *after* the doc comment wasn't expected. Added a check that the found token is something that "conceptually" closes the previous item before emitting that error, otherwise just complain about the missing identifier.
In both of the following cases, the syntax error follows a doc comment:
```
error: expected identifier, found keyword `Self`
--> $DIR/doc-before-bad-variant.rs:4:5
|
LL | enum TestEnum {
| -------- while parsing this enum
...
LL | Self,
| ^^^^ expected identifier, found keyword
|
= help: enum variants can be `Variant`, `Variant = <integer>`, `Variant(Type, ..., TypeN)` or `Variant { fields: Types }`
```
```
error: expected identifier, found `<`
--> $DIR/doc-before-syntax-error.rs:2:1
|
LL | <>
| ^ expected identifier
```
Fix#71982.
Pattern Migration 2024: properly label `&` patterns whose subpatterns are from macro expansions
See the failing test output in the first commit for an example of what this going wrong looks like. The error/lint diagnostic tries to point to just the `&` or `&mut` of reference patterns when labeling the causes, to make the output clearer (#134394). The trimming there wasn't quite right though: it used the interior of the reference pattern as a cutoff and extended backwards to find where to trim the pattern's span, but this breaks if the `&` and the interior are from different sources. This PR instead trims by starting at the start of the pattern and ending at the final character of the `&` (or `&mut`, `ref`, `ref mut`, or `mut`, depending on what the error/lint is labeling); that way, there's no opportunity for failure from mixing sources.
I'm not 100% happy with this approach, but I'm also not sure what the best practices are as far as hacky `SourceMap` munching goes, so please let me know if something else would be preferred.
Since `SourceMap::span_through_char` can't change the syntax context of the span, I've also removed a call to `Span::with_ctxt` (we care about the edition of the span in question since this is a hard error in Rust 2024). If we want to be extra safe in case that changes, I can re-add it or track error hardness separately in the `rust_2024_migration_desugared_pats` table.
Register `USAGE_OF_TYPE_IR_INHERENT`, remove inherent usages
I implemented a lint to discourage the usage of `rustc_type_ir::inherent` but never actually enabled it. People started using `rustc_type_ir::inherent` methods through globs, lol.
r? fmease or reassign as you please
Make fewer crates depend on `rustc_ast_ir`
I think it simplifies the crate graph and also exposes people less to confusion if downstream crates don't interact with `rustc_ast_ir` directly and instead just use its functionality reexported through more familiar paths.
r? oli-obk since you introduced ast-ir
Restrict `bevy_ecs` `ParamSet` hack
This limits the bevy WF hack to only apply to ADTs named `ParamSet` that come from crates named `bevy_ecs`, and references to the latter.
Previously, we were applying it to all ADTs that contained the substring `"ParamSet"`. This could show up anywhere in the ADT name, and it could come from any crate. It's a bit concerning since other code could theoretically begin to rely on this behavior too (though I don't expect it to)
This simplifies the logic a bit and turns it into a visitor.
r? `@jackh726`
Add customized compare for Link in rustdoc
Maybe some other types in sidebar need to be sorted in this way, maybe add this crate `natord` is ok?
r? clubby789
Fixes#137098
interpret: adjust vtable validity check for higher-ranked types
## What
Transmuting between trait objects where a generic argument or associated type only differs in bound regions (not bound at or above the trait object's binder) is now UB. For example
* transmuting between `&dyn Trait<for<'a> fn(&'a u8)>` and `&dyn Trait<fn(&'static u8)>` is UB.
* transmuting between `&dyn Trait<Assoc = for<'a> fn(&'a u8)>` and `&dyn Trait<Assoc = fn(&'static u8)>` is UB.
* transmuting between `&dyn Trait<for<'a> fn(&'a u8) -> (&'a u8, &'static u8)>` and `&dyn Trait<for<'a> fn(&'a u8) -> (&'static u8, &'a u8)>` is UB.
Transmuting between subtypes (in either direction) is still allowed, which means that bound regions that are bound at or above the trait object's binder can still be changed:
* transmuting between `&dyn for<'a> Trait<fn(&'a u8)>` and `&dyn for Trait<fn(&'static u8)>` is fine.
* transmuting between `&dyn for<'a> Trait<dyn Trait<fn(&'a u8)>>` and `&dyn for Trait<dyn Trait<fn(&'static u8)>>` is fine.
## Why
Very similar to https://github.com/rust-lang/rust/issues/120217 and https://github.com/rust-lang/rust/issues/120222, changing a trait object's generic argument to a type that only differs in bound regions can still affect the vtable layout and lead to segfaults at runtime (for an example see `src/tools/miri/tests/fail/validity/dyn-transmute-inner-binder.rs`).
Since we already already require that the trait object predicates must be equal modulo bound regions, it is only natural to extend this check to also require type equality considering bound regions.
However, it also makes sense to allow transmutes between a type and a subtype thereof. For example `&dyn for<'a> Trait<&'a u8>` is a subtype of `&dyn Trait<&'static ()>` and they are guaranteed to have the same vtable, so it makes sense to allow this transmute. So that's why bound lifetimes that are bound to the trait object itself are treated as free lifetime for the purpose of this check.
Note that codegen already relies on the property that subtyping cannot change the the vtable and this is asserted here (note the leak check): 251206c27b/compiler/rustc_codegen_ssa/src/base.rs (L106-L153)
Furthermore, we allow some pointer-to-pointer casts like `*const dyn for<'a> Trait<&'a u8>` to `*const Wrapper<dyn Trait<&'static u8>>` that instantiate the trait object binder and are currently lowered to a single pointer-to-pointer cast in MIR (`CastKind::PtrToPtr`) and *not* an unsizing coercion (`CastKind::PointerCoercion(Unsize)`), so the current MIR lowering of these would be UB if we didn't allow subtyping transmutes.
---
fixes https://github.com/rust-lang/rust/issues/135230
cc `@rust-lang/opsem`
r? `@compiler-errors` for the implementation
Organize `OsString`/`OsStr` shims
Synchronize the `bytes.rs` and `wtf8.rs` shims for `OsString`/`OsStr` so they're easier to diff between each other. This is mostly ordering items the same between the two. I tried to minimize moves and went for the average locations between the files.
With them in the same order, it is clear that `FromInner<_>` is not implemented for `bytes::Buf` and `Clone::clone_from` is not implemented for `wtf8::Buf`, but they are for the other. Fix that.
I added #[inline] to all inherent methods of the `OsString`/`OsStr` shims, because it seemed that was already the rough pattern. `bytes.rs` has more inlining than `wtf8.rs`, so I added the corresponding ones to `wtf8.rs`. Then, the common missing ones have no discernible pattern to me. They're not divided by non-allocating/allocating. Perhaps the pattern is that UTF-8 validation isn't inlined? Since these types are merely the inner values in `OsStr`/`OsString`, I put inline on all methods and let those public types dictate inlining. I have not inspected codegen or run benchmarks.
Also, touch up some (private) documentation comments.
r? ``````@ChrisDenton``````
