Replace an FTP link in comments with an equivalent HTTPS link
Modern browsers and editors often don't support following FTP links, so using an ordinary web link gives the same result in a more convenient way.
Consider param-env candidates even if they have errors
I added this logic in https://github.com/rust-lang/rust/pull/106309, but frankly I don't know why -- the logic was a very large hammer. It seems like recent changes to error tainting has made that no longer necessary.
Ideally we'd rework the way we handle error reporting in all of candidate assembly to be a bit more responsible; we're just suppressing candidates all willy-nilly and it leads to mysterious *other* errors cropping up, like the one that #132082 originally wanted to fix.
**N.B.** This has the side-effect of turning a failed resolution like `where Missing: Sized` into a trivial where clause that matches all types, but also I don't think it really matters?
I'm putting this up as an alternative to #132082, since that PR doesn't address the case when one desugars the APIT into a regular type param.
r? lcnr vibeck
Taking a raw ref (`&raw (const|mut)`) of a deref of pointer (`*ptr`) is always safe
T-opsem decided in https://github.com/rust-lang/reference/pull/1387 that `*ptr` is only unsafe if the place is accessed. This means that taking a raw ref of a deref expr is always safe, since it doesn't constitute a read.
This also relaxes the `DEREF_NULLPTR` lint to stop warning in the case of raw ref of a deref'd nullptr, and updates its docs to reflect that change in the UB specification.
This does not change the behavior of `addr_of!((*ptr).field)`, since field projections still require the projection is in-bounds.
I'm on the fence whether this requires an FCP, since it's something that is guaranteed by the reference you could ostensibly call this a bugfix since we were counting truly safe operations as unsafe. Perhaps someone on opsem has a strong opinion? cc `@rust-lang/opsem`
HashStable for rustc_feature::Features: stop hashing compile-time constant
It seems like back in 542bc75dea this was added as "hash the boolean value of each lang feature", but then in 1487bd6a17 this got split into first hashing a sequence of `bool`s (representing all the features) and then hashing all the feature names... but the list of feature names is a compile-time constant, so it seems entirely unnecessary to hash them?
Cc `@Mark-Simulacrum` who wrote the second of the commits mentioned above.
Cc `@nnethercote`
coverage: Pass coverage mappings to LLVM as separate structs
Instead of trying to cram *N* different kinds of coverage mapping data into a single list for FFI, pass *N* different lists of simpler structs.
This avoids the need to fill unused fields with dummy values, and avoids the need to tag structs with their underlying kind. It also lets us call the dedicated LLVM constructors for each different mapping type, instead of having to go through the complex general-purpose constructor.
Even though this adds multiple new structs to the FFI surface area, the resulting C++ code is simpler and shorter.
---
I've structured this mostly as a single atomic patch, rather than a series of incremental changes, because that avoids the need to make fiddly fixes to code that is about to be deleted anyway.
minor `*dyn` cast cleanup
Small follow-up to https://github.com/rust-lang/rust/pull/130234 to remove a redundant check and clean up comments. No functional changes.
Also, explain why casts cannot drop the principal even though coercions can, and add a test because apparently we didn't have one already.
r? `@WaffleLapkin` or `@compiler-errors`
Deeply normalize `TypeTrace` when reporting type error in new solver
Normalize the values that come from the `TypeTrace` for various type mismatches.
Side-note: We can't normalize the `TypeError` itself bc it may come from instantiated binders, so it may reference values from within the probe...
r? lcnr
Fix `target_vendor` in QNX Neutrino targets
The `x86_64-pc-nto-qnx710` and `i586-pc-nto-qnx700` targets have `pc` in their target triple names, but the vendor was set to the default `"unknown"`.
CC target maintainers `@flba-eb,` `@gh-tr,` `@jonathanpallant` and `@japaric`
Rename Receiver -> LegacyReceiver
As part of the "arbitrary self types v2" project, we are going to replace the current `Receiver` trait with a new mechanism based on a new, different `Receiver` trait.
This PR renames the old trait to get it out the way. Naming is hard. Options considered included:
* HardCodedReceiver (because it should only be used for things in the standard library, and hence is sort-of hard coded)
* LegacyReceiver
* TargetLessReceiver
* OldReceiver
These are all bad names, but fortunately this will be temporary. Assuming the new mechanism proceeds to stabilization as intended, the legacy trait will be removed altogether.
Although we expect this trait to be used only in the standard library, we suspect it may be in use elsehwere, so we're landing this change separately to identify any surprising breakages.
It's known that this trait is used within the Rust for Linux project; a patch is in progress to remove their dependency.
This is a part of the arbitrary self types v2 project,
https://github.com/rust-lang/rfcs/pull/3519https://github.com/rust-lang/rust/issues/44874
r? `@wesleywiser`
Rollup of 9 pull requests
Successful merges:
- #130991 (Vectorized SliceContains)
- #131928 (rustdoc: Document `markdown` module.)
- #131955 (Set `signext` or `zeroext` for integer arguments on RISC-V and LoongArch64)
- #131979 (Minor tweaks to `compare_impl_item.rs`)
- #132036 (Add a test case for #131164)
- #132039 (Specialize `read_exact` and `read_buf_exact` for `VecDeque`)
- #132060 ("innermost", "outermost", "leftmost", and "rightmost" don't need hyphens)
- #132065 (Clarify documentation of `ptr::dangling()` function)
- #132066 (Fix a typo in documentation of `pointer::sub_ptr()`)
r? `@ghost`
`@rustbot` modify labels: rollup
"innermost", "outermost", "leftmost", and "rightmost" don't need hyphens
These are all standard dictionary words and don't require hyphenation.
-----
Encountered an instance of this in error messages and it bugged me, so I
figured I'd fix it across the entire codebase.
Minor tweaks to `compare_impl_item.rs`
1. Stop using the `InstantiatedPredicates` struct for `hybrid_preds` in `compare_impl_item.rs`, since we never actually push anything into the `spans` part of it.
2. Remove redundant impl args and don't do useless identity substitution, prefer calling `instantiate_identity`.
Set `signext` or `zeroext` for integer arguments on RISC-V and LoongArch64
This PR contains 3 commits:
- the first one introduces a new function `adjust_for_rust_abi` in `rustc_target`, and moves the x86 specific adjustment code into it;
- the second one adds RISC-V specific adjustment code into it, which sets `signext` or `zeroext` attribute for integer arguments.
- **UPDATE**: added the 3rd commit to apply the same adjustment for LoongArch64.
Add wasm32v1-none target (compiler-team/#791)
This is a preliminary implementation of the MCP discussed in [compiler-team#791](https://github.com/rust-lang/compiler-team/issues/791). It's not especially "major" but you know, process! Anyway it adds a new wasm32v1-none target which just pins down a set of wasm features. I think this is close to the consensus that emerged when discussing it on Zulip so I figured I'd sketch to see how hard it is. Turns out not very.
nightly feature tracking: get rid of the per-feature bool fields
The `struct Features` that tracks which features are enabled has a ton of public `bool`-typed fields that are basically caching the result of looking up the corresponding feature in `enabled_lang_features`. Having public fields with an invariant is not great, so at least they should be made private. However, it turns out caching these lookups is actually [not worth it](https://github.com/rust-lang/rust/pull/131321#issuecomment-2402068336), so this PR just entirely gets rid of these fields. (The alternative would be to make them private and have a method for each of them to expose them in a read-only way. Most of the diff of this PR would be the same in that case.)
r? `@nnethercote`
do not implement `Relate` for "boring" types
and update some macros while we're at it. This means we don't have to implement `TypeVisitable` for them.
r? `@compiler-errors`
analyse: remove unused uncanonicalized field
This field is unused and was only relevant when actually printing proof trees. Right now this simply causes proof tree building to leak a bunch of inference vars 😁
r? ``@compiler-errors``
Represent `hir::TraitBoundModifiers` as distinct parts in HIR
Stop squashing distinct `polarity` and `constness` into a single `hir::TraitBoundModifier`.
This PR doesn't attempt to handle all the corner cases correctly, since the old code certainly did not either; but it should be much easier for, e.g., rustc devs working on diagnostics, or clippy devs, to actually handle constness and polarity correctly.
try-job: x86_64-gnu-stable
x86-32 float return for 'Rust' ABI: treat all float types consistently
This helps with https://github.com/rust-lang/rust/issues/131819: for our own ABI on x86-32, we want to *never* use the float registers. The previous logic only considered F32 and F64, but skipped F16 and F128. So I made the logic just apply to all float types.
try-job: i686-gnu
try-job: i686-gnu-nopt
Rollup of 8 pull requests
Successful merges:
- #125205 (Fixup Windows verbatim paths when used with the `include!` macro)
- #131049 (Validate args are correct for `UnevaluatedConst`, `ExistentialTraitRef`/`ExistentialProjection`)
- #131549 (Add a note for `?` on a `impl Future<Output = Result<..>>` in sync function)
- #131731 (add `TestFloatParse` to `tools.rs` for bootstrap)
- #131732 (Add doc(plugins), doc(passes), etc. to INVALID_DOC_ATTRIBUTES)
- #132006 (don't stage-off to previous compiler when CI rustc is available)
- #132022 (Move `cmp_in_dominator_order` out of graph dominator computation)
- #132033 (compiletest: Make `line_directive` return a `DirectiveLine`)
r? `@ghost`
`@rustbot` modify labels: rollup
Move `cmp_in_dominator_order` out of graph dominator computation
Dominator-order information is only needed for coverage graphs, and is easy enough to collect by just traversing the graph again.
This avoids wasted work when computing graph dominators for any other purpose.
Add a note for `?` on a `impl Future<Output = Result<..>>` in sync function
It's confusing to `?` a future of a result in a sync function. We have a suggestion to `.await` it if we're in an async function, but not a sync function. Note that this is the case for sync functions, at least.
Let's be a bit more vague about a fix, since it's somewhat context dependent. For example, you could block on it, or you could make your function asynchronous. 🤷
Validate args are correct for `UnevaluatedConst`, `ExistentialTraitRef`/`ExistentialProjection`
For the `Existential*` ones, we have to do some adjustment to the args list to deal with the missing `Self` type, so we introduce a `debug_assert_existential_args_compatible` function to the interner as well.
Fixup Windows verbatim paths when used with the `include!` macro
On Windows, the following code can fail if the `OUT_DIR` environment variable is a [verbatim path](https://doc.rust-lang.org/std/path/enum.Prefix.html) (i.e. begins with `\\?\`):
```rust
include!(concat!(env!("OUT_DIR"), "/src/repro.rs"));
```
This is because verbatim paths treat `/` literally, as if it were just another character in the file name.
The good news is that the standard library already has code to fix this. We can simply use `components` to normalize the path so it works as intended.
As part of the "arbitrary self types v2" project, we are going to
replace the current `Receiver` trait with a new mechanism based on a
new, different `Receiver` trait.
This PR renames the old trait to get it out the way. Naming is hard.
Options considered included:
* HardCodedReceiver (because it should only be used for things in the
standard library, and hence is sort-of hard coded)
* LegacyReceiver
* TargetLessReceiver
* OldReceiver
These are all bad names, but fortunately this will be temporary.
Assuming the new mechanism proceeds to stabilization as intended, the
legacy trait will be removed altogether.
Although we expect this trait to be used only in the standard library,
we suspect it may be in use elsehwere, so we're landing this change
separately to identify any surprising breakages.
It's known that this trait is used within the Rust for Linux project; a
patch is in progress to remove their dependency.
This is a part of the arbitrary self types v2 project,
https://github.com/rust-lang/rfcs/pull/3519https://github.com/rust-lang/rust/issues/44874
r? @wesleywiser
terminology: #[feature] *enables* a feature (instead of "declaring" or "activating" it)
Mostly, we currently call a feature that has a corresponding `#[feature(name)]` attribute in the current crate a "declared" feature. I think that is confusing as it does not align with what "declaring" usually means. Furthermore, we *also* refer to `#[stable]`/`#[unstable]` as *declaring* a feature (e.g. in [these diagnostics](f25e5abea2/compiler/rustc_passes/messages.ftl (L297-L301))), which aligns better with what "declaring" usually means. To make things worse, the functions `tcx.features().active(...)` and `tcx.features().declared(...)` both exist and they are doing almost the same thing (testing whether a corresponding `#[feature(name)]` exists) except that `active` would ICE if the feature is not an unstable lang feature. On top of this, the callback when a feature is activated/declared is called `set_enabled`, and many comments also talk about "enabling" a feature.
So really, our terminology is just a mess.
I would suggest we use "declaring a feature" for saying that something is/was guarded by a feature (e.g. `#[stable]`/`#[unstable]`), and "enabling a feature" for `#[feature(name)]`. This PR implements that.
Dominator-order information is only needed for coverage graphs, and is easy
enough to collect by just traversing the graph again.
This avoids wasted work when computing graph dominators for any other purpose.
coverage: Make counter creation handle node/edge counters more uniformly
Similar to #130380, this is another round of small improvements informed by my ongoing attempts to overhaul coverage counter creation.
One of the big benefits is getting rid of the awkward special-case that would sometimes attach an edge counter to a node instead. That was needed by the code that chooses which out-edge should be given a counter expression, but we can avoid that by making the corresponding check a little smarter.
I've also renamed several things to be simpler and more consistent, which should help with future changes.
Always specify `llvm_abiname` for RISC-V targets
For RISC-V targets, when `llvm_abiname` is not specified LLVM will infer the ABI from the target features, causing #116344 to occur. This PR adds the correct `llvm_abiname` to all RISC-V targets where it is missing (which are all soft-float targets), and adds a test to prevent future RISC-V targets from accidentally omitting `llvm_abiname`. The only affect of this PR is that `-Ctarget-feature=+f` (or similar) will no longer affect the ABI on the modified targets.
<!-- homu-ignore:start -->
r? `@RalfJung`
<!--- homu-ignore:end -->
rust_for_linux: -Zregparm=<N> commandline flag for X86 (#116972)
Command line flag `-Zregparm=<N>` for X86 (32-bit) for rust-for-linux: https://github.com/rust-lang/rust/issues/116972
Implemented in the similar way as fastcall/vectorcall support (args are marked InReg if fit).
make unsupported_calling_conventions a hard error
This has been a future-compat lint (not shown in dependencies) since Rust 1.55, released 3 years ago. Hopefully that was enough time so this can be made a hard error now. Given that long timeframe, I think it's justified to skip the "show in dependencies" stage. There were [not many crates hitting this](https://github.com/rust-lang/rust/pull/86231#issuecomment-866300943) even when the lint was originally added.
This should get cratered, and I assume then it needs a t-compiler FCP. (t-compiler because this looks entirely like an implementation oversight -- for the vast majority of ABIs, we already have a hard error, but some were initially missed, and we are finally fixing that.)
Fixes https://github.com/rust-lang/rust/pull/87678
Dont consider predicates that may hold as impossible in `is_impossible_associated_item`
Use infer vars to account for ambiguities when considering if methods are impossible to instantiate for a given self type. Also while we're at it, let's use the new trait solver instead of `evaluate` since this is used in rustdoc.
r? lcnr
Fixes#131839
stabilize Strict Provenance and Exposed Provenance APIs
Given that [RFC 3559](https://rust-lang.github.io/rfcs/3559-rust-has-provenance.html) has been accepted, t-lang has approved the concept of provenance to exist in the language. So I think it's time that we stabilize the strict provenance and exposed provenance APIs, and discuss provenance explicitly in the docs:
```rust
// core::ptr
pub const fn without_provenance<T>(addr: usize) -> *const T;
pub const fn dangling<T>() -> *const T;
pub const fn without_provenance_mut<T>(addr: usize) -> *mut T;
pub const fn dangling_mut<T>() -> *mut T;
pub fn with_exposed_provenance<T>(addr: usize) -> *const T;
pub fn with_exposed_provenance_mut<T>(addr: usize) -> *mut T;
impl<T: ?Sized> *const T {
pub fn addr(self) -> usize;
pub fn expose_provenance(self) -> usize;
pub fn with_addr(self, addr: usize) -> Self;
pub fn map_addr(self, f: impl FnOnce(usize) -> usize) -> Self;
}
impl<T: ?Sized> *mut T {
pub fn addr(self) -> usize;
pub fn expose_provenance(self) -> usize;
pub fn with_addr(self, addr: usize) -> Self;
pub fn map_addr(self, f: impl FnOnce(usize) -> usize) -> Self;
}
impl<T: ?Sized> NonNull<T> {
pub fn addr(self) -> NonZero<usize>;
pub fn with_addr(self, addr: NonZero<usize>) -> Self;
pub fn map_addr(self, f: impl FnOnce(NonZero<usize>) -> NonZero<usize>) -> Self;
}
```
I also did a pass over the docs to adjust them, because this is no longer an "experiment". The `ptr` docs now discuss the concept of provenance in general, and then they go into the two families of APIs for dealing with provenance: Strict Provenance and Exposed Provenance. I removed the discussion of how pointers also have an associated "address space" -- that is not actually tracked in the pointer value, it is tracked in the type, so IMO it just distracts from the core point of provenance. I also adjusted the docs for `with_exposed_provenance` to make it clear that we cannot guarantee much about this function, it's all best-effort.
There are two unstable lints associated with the strict_provenance feature gate; I moved them to a new [strict_provenance_lints](https://github.com/rust-lang/rust/issues/130351) feature since I didn't want this PR to have an even bigger FCP. ;)
`@rust-lang/opsem` Would be great to get some feedback on the docs here. :)
Nominating for `@rust-lang/libs-api.`
Part of https://github.com/rust-lang/rust/issues/95228.
[FCP comment](https://github.com/rust-lang/rust/pull/130350#issuecomment-2395114536)
Finish stabilization of `result_ffi_guarantees`
The internal linting has been changed, so all that is left is making sure we stabilize what we want to stabilize.
Rollup of 4 pull requests
Successful merges:
- #126588 (Added more scenarios where comma to be removed in the function arg)
- #131728 (bootstrap: extract builder cargo to its own module)
- #131968 (Rip out old effects var handling code from traits)
- #131981 (Remove the `BoundConstness::NotConst` variant)
r? `@ghost`
`@rustbot` modify labels: rollup
Rip out old effects var handling code from traits
Traits no longer have an effect parameter, so this removes logic associated with it. It also removes logic surrounding confirming `~const Destruct` bounds, which I added a looooong time ago, and which I don't feel like we need anymore -- if it needs to be added back, it should be rewritten :D
cc `@fee1-dead`
Added more scenarios where comma to be removed in the function arg
This is an attempt to address the problem methion in https://github.com/rust-lang/rust/issues/106304#issuecomment-1837273666.
Copy the annotation to explain the fix
If the next Error::Extra ("next") doesn't next to current ("current")
```
fn foo(_: (), _: u32) {}
- foo("current", (), 1u32, "next")
+ foo((), 1u32)
```
If the previous error is not a `Error::Extra`, then do not trim the next comma
```
- foo((), "current", 42u32, "next")
+ foo((), 42u32)
```
Frankly, this is a fix from a test case and may not cover all scenarios
Continue to get rid of `ty::Const::{try_}eval*`
This PR mostly does:
* Removes all of the `try_eval_*` and `eval_*` helpers from `ty::Const`, and replace their usages with `try_to_*`.
* Remove `ty::Const::eval`.
* Rename `ty::Const::normalize` to `ty::Const::normalize_internal`. This function is still used in the normalization code itself.
* Fix some weirdness around the `TransmuteFrom` goal.
I'm happy to split it out further; for example, I could probably land the first part which removes the helpers, or the changes to codegen which are more obvious than the changes to tools.
r? BoxyUwU
Part of https://github.com/rust-lang/rust/issues/130704
Remove `lower_mono_bounds`
I'm not convinced about the usefulness of `lower_mono_bounds`, especially since we have *so* many lower-bound-like fns in HIR lowering, so I've just inlined it into its callers.
`optimize` attribute applied to things other than methods/functions/c…
…losures gives an error (#128488)
Duplicate of #128943, which I had accidentally closed when rebasing.
cc. `@jieyouxu` `@compiler-errors` `@nikomatsakis` `@traviscross` `@pnkfelix.`
Make `llvm::set_section` take a `&CStr`
There's no reason to convert the section name to an intermediate `String`, when the LLVM-C API wants a C string anyway.
Follow-up to #131876.
compiler: Error on layout of enums with invalid reprs
Surprising no one, the ICEs with the same message have the same root cause.
Invalid reprs can reach layout computation for various reasons. For instance, the compiler may want to use its layout computations to discern if a combination of layout-affecting attributes results in a valid type to begin with by e.g. computing its size. When the input is bad, return an error reflecting that the answer to the question is not a useful one.
Allow `#[deny]` inside `#[forbid]` as a no-op
Forbid cannot be overriden. When someome tries to do this anyways, it results in a hard error. That makes sense.
Except it doesn't, because macros. Macros may reasonably use `#[deny]` (or `#[warn]` for an allow-by-default lint) in their expansion to assert that their expanded code follows the lint. This is doesn't work when the output gets expanded into a `forbid()` context. This is pretty silly, since both the macros and the code agree on the lint!
By making it a warning instead, we remove the problem with the macro, which is now nothing as warnings are suppressed in macro expanded code, while still telling users that something is up.
fixes#121483
Just because the code says it's OK does not mean that it actually is OK.
Nodes with the same total size were not sorted, their order relied on
hashmap iteration.
compiler: Adopt rust-analyzer impls for `LayoutCalculatorError`
We're about to massively churn the internals of `rustc_abi`. To minimize the immediate and future impact on rust-analyzer, as a subtree that depends on this crate, grow some API on `LayoutCalculatorError` that reflects their uses of it. This way we can nest the type in theirs, and they can just call functions on it without having to inspect and flatten-out its innards.
refactor fudge_inference, handle effect vars
this makes it easier to use fudging outside of `fudge_inference_if_ok`, which is likely necessary to handle inference variable leaks on rollback.
We now also uses exhaustive matches where possible and improve the code to handle effect vars.
r? `@compiler-errors` `@BoxyUwU`
Get rid of `OnlySelfBounds`
We turn `PredicateFilter` into a newtyped bool called `OnlySelfBounds`. There's no reason to lose the information of the `PredicateFilter`, so let's just pass it all the way through.
Remove unnecessary constness from `lower_generic_args_of_path`
We pass `NotConst` to all callsites of `lower_generic_args_of_path` except for `lower_poly_trait_ref`, so let's not do that.
Stop inverting expectation in normalization errors
We have some funky special case logic to invert the expectation and actual type for normalization errors depending on their cause code. IMO most of the error messages get better, except for `try {}` blocks' type expectations. I think that these need to be special cased in some other way, rather than via this hack.
Fixes#131763
Make sure that outer opaques capture inner opaques's lifetimes even with precise capturing syntax
When lowering an opaque, we must capture and duplicate all of the lifetimes in the opaque's bounds to correctly lower the opaque's bounds. We do this *even if* the lifetime is not captured according to the `+ use<>` precise capturing bound; in that case, we will later reject that captured lifetime. For example, Given an opaque like `impl Sized + 'a + use<>`, we will still duplicate `'a` but later error that it is not mentioned in the `use<>` bound.
The current heuristic was not properly handling cases like:
```
//@ edition: 2024
fn foo<'a>() -> impl Trait<Assoc = impl Trait2> + use<> {}
```
Which forces the outer `impl Trait` to capture `'a` since `impl Trait2` *implicitly* captures `'a` due to the new lifetime capture rules for edition 2024. We were only capturing lifetimes syntactically mentioned in the bounds. (Note that this still is an error; we just need to capture `'a` so it is handled later in the compiler correctly -- hence the ICE in #131769 where a late-bound lifetime was being referenced outside of its binder).
This PR reworks the way we collect lifetimes to capture and duplicate in AST lowering to fix this.
Fixes#131769
warn less about non-exhaustive in ffi
Bindgen allows generating `#[non_exhaustive] #[repr(u32)]` enums. This results in nonintuitive nonlocal `improper_ctypes` warnings, even when the types are otherwise perfectly valid in C.
Adjust for actual tooling expectations by avoiding warning on simple enums with only unit variants.
Closes https://github.com/rust-lang/rust/issues/116831
Migrate `llvm::set_comdat` and `llvm::SetUniqueComdat` to LLVM-C FFI.
Note, now we can call `llvm::set_comdat` only when the target actually
supports adding comdat. As this has no convenient LLVM-C API, we
implement this as `TargetOptions::supports_comdat`.
Co-authored-by: Stuart Cook <Zalathar@users.noreply.github.com>
small interpreter error cleanup
- Add `InterpretResult::map_err_kind` for the common case of swapping out the error kind (while preserving the backtrace pointing to the original error source)
- Rename `InterpError` -> `InterpErrorKind` to be consistent with the `kind` field name, and make it more clear that this is not the final error type
Return values larger than 2 registers using a return area pointer
LLVM and Cranelift disagree about how to return values that don't fit in the registers designated for return values. LLVM will force the entire return value to be passed by return area pointer, while Cranelift will look at each IR level return value independently and decide to pass it in a register or not, which would result in the return value being passed partially in registers and partially through a return area pointer.
While Cranelift may need to be fixed as the LLVM behavior is generally more correct with respect to the surface language, forcing this behavior in rustc itself makes it easier for other backends to conform to the Rust ABI and for the C ABI rustc already handles this behavior anyway.
In addition LLVM's decision to pass the return value in registers or using a return area pointer depends on how exactly the return type is lowered to an LLVM IR type. For example `Option<u128>` can be lowered as `{ i128, i128 }` in which case the x86_64 backend would use a return area pointer, or it could be passed as `{ i32, i128 }` in which case the x86_64 backend would pass it in registers by taking advantage of an LLVM ABI extension that allows using 3 registers for the x86_64 sysv call conv rather than the officially specified 2 registers.
This adjustment is only necessary for the Rust ABI as for other ABI's the calling convention implementations in rustc_target already ensure any return value which doesn't fit in the available amount of return registers is passed in the right way for the current target.
Helps with https://github.com/rust-lang/rustc_codegen_cranelift/issues/1525
cc https://github.com/bytecodealliance/wasmtime/issues/9250
Before this change, adding a lint was a difficult matter
because it always had some overhead involved. This was
because all lints would run, no matter their default level,
or if the user had #![allow]ed them. This PR changes that
Forbid cannot be overriden. When someome tries to do this anyways,
it results in a hard error. That makes sense.
Except it doesn't, because macros. Macros may reasonably use `#[deny]`
in their expansion to assert
that their expanded code follows the lint. This is doesn't work when the
output gets expanded into a `forbid()` context. This is pretty silly,
since both the macros and the code agree on the lint!
Therefore, we allow `#[deny(..)]`ing a lint that's already forbidden,
keeping the level at forbid.
Never emit `vptr` for empty/auto traits
Emiting `vptr`s for empty/auto traits is unnecessary (#114942) and causes unsoundness in `trait_upcasting` (#131813). This PR should ensure that we never emit vtables for such traits. See the linked issues for more details.
I'm not sure if I can add tests for the vtable layout. So this PR only adds tests for the soundness hole (i.e., the segmentation fault will disappear after this PR).
Fixes#114942Fixes#131813
Cc #65991 (tracking issue for `trait_upcasting`)
r? `@WaffleLapkin` (per https://github.com/rust-lang/rust/issues/131813#issuecomment-2419969745)
Default to the medium code model on OpenHarmony LoongArch target
The context for this is #130266: setting the medium code model for the `loongarch64-linux-ohos` target.
r? ```@jieyouxu```
Dont ICE when computing coverage of synthetic async closure body
I'm not totally certain if this is *right*, but at least it doesn't ICE.
The issue is that we end up generating two MIR bodies for each async closure, since the `FnOnce` and `Fn`/`FnMut` implementations have different borrowing behavior of their captured variables. They should ideally both contribute to the coverage, since those MIR bodies are (*to the user*) the same code and should have no behavioral differences.
This PR at least suppresses the ICEs, and then I guess worst case we can fix this the right way later.
r? Zalathar or re-roll
Fixes#131190
Allow dropping dyn principal
Revival of #126660, which was a revival of #114679. Fixes#126313.
Allows dropping principal when coercing trait objects, e.g. `dyn Debug + Send` -> `dyn Send`.
cc `@compiler-errors` `@Jules-Bertholet`
r? `@lcnr`
compiler: use `is_none_or` where it is clearly better
heuristic was: if it easily allows removing bangs entirely? worth it. if it requires more effort or just moves the bang? not.
cleanup canonical queries
best reviewed commit by commit. adding `CanonicalQueryInput` to stop returning `defining_opaque_types` in query responses is the most involved change here.
r? ``@compiler-errors``
Setting up indirect access to external data for loongarch64-linux-{musl,ohos}
In issue #118053, the `loongarch64-unknown-linux-gnu` target needs indirection to access external data, and so do the `loongarch64-unknown-linux-musl` and `loongarch64-unknown-linux-ohos` targets.
Make destructors on `extern "C"` frames to be executed
This would make the example in #123231 print "Noisy Drop". I didn't mark this as fixing the issue because the behaviour is yet to be spec'ed.
Tracking:
- https://github.com/rust-lang/rust/issues/74990
Fix needless_lifetimes in stable_mir
Hi,
This PR fixes the following clippy warning
```
warning: the following explicit lifetimes could be elided: 'a
--> compiler/stable_mir/src/mir/visit.rs:490:6
|
490 | impl<'a> PlaceRef<'a> {
| ^^ ^^
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_lifetimes
= note: `#[warn(clippy::needless_lifetimes)]` on by default
help: elide the lifetimes
|
490 - impl<'a> PlaceRef<'a> {
490 + impl PlaceRef<'_> {
|
```
Best regards,
Michal
Fix trivially_copy_pass_by_ref in stable_mir
Hi,
This PR fixes the following clippy warnings
```
warning: this argument (8 byte) is passed by reference, but would be more efficient if passed by value (limit: 8 byte)
--> compiler/stable_mir/src/mir/body.rs:1042:34
|
1042 | fn subslice_ty(ty: Ty, from: &u64, to: &u64, from_end: &bool) -> Result<Ty, Error> {
| ^^^^ help: consider passing by value instead: `u64`
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#trivially_copy_pass_by_ref
= note: requested on the command line with `-W clippy::trivially-copy-pass-by-ref`
warning: this argument (8 byte) is passed by reference, but would be more efficient if passed by value (limit: 8 byte)
--> compiler/stable_mir/src/mir/body.rs:1042:44
|
1042 | fn subslice_ty(ty: Ty, from: &u64, to: &u64, from_end: &bool) -> Result<Ty, Error> {
| ^^^^ help: consider passing by value instead: `u64`
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#trivially_copy_pass_by_ref
warning: this argument (1 byte) is passed by reference, but would be more efficient if passed by value (limit: 8 byte)
--> compiler/stable_mir/src/mir/body.rs:1042:60
|
1042 | fn subslice_ty(ty: Ty, from: &u64, to: &u64, from_end: &bool) -> Result<Ty, Error> {
| ^^^^^ help: consider passing by value instead: `bool`
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#trivially_copy_pass_by_ref
```
Best regards,
Michal
Rename `can_coerce` to `may_coerce`, and then structurally resolve correctly in the probe
We need to structurally resolve the lhs and rhs of the coercion. Also, renaming the method so it's less ambiguous about what it's doing... the word "may" gives more clear signal that it has false positives imo.
r? lcnr
Don't check unsize goal in MIR validation when opaques remain
Similarly to `mir_assign_valid_types`, let's just skip when there are opaques. Fixes#130921.
Fix explicit_iter_loop in rustc_serialize
Hi,
This PR fixes some clippy warnings
```
warning: it is more concise to loop over references to containers instead of using explicit iteration methods
--> compiler/rustc_serialize/src/serialize.rs:675:18
|
675 | for e in self.iter() {
| ^^^^^^^^^^^ help: to write this more concisely, try: `self`
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#explicit_iter_loop
```
Best regards,
Michal
Try to improve error messages involving aliases in the solver
1. Treat aliases as rigid only if it may not be defined and it's well formed (i.e. for projections, its trait goal is satisfied).
2. Record goals that are related to alias normalization under a new `GoalKind`, so we can look into them in the `BestObligation` visitor.
3. Try to deduplicate errors due to self types of goals that are un-normalizable aliases.
r? lcnr
Add fast-path when computing the default visibility
This PR adds (or more correctly re-adds the) fast-path when computing the default visibility, by taking advantage of the fact that the "interposable" requested visibility always return the "default" codegen visibility.
Should address the small regression observed in https://github.com/rust-lang/rust/pull/131111#issuecomment-2402273967.
r? `@lqd`
Implement edition 2024 match ergonomics restrictions
This implements the minimalest version of [match ergonomics for edition 2024](https://rust-lang.github.io/rfcs/3627-match-ergonomics-2024.html). This minimal version makes it an error to ever reset the default binding mode. The implemented proposal is described precisely [here](https://hackmd.io/zUqs2ISNQ0Wrnxsa9nhD0Q#RFC-3627-nano), where it is called "RFC 3627-nano".
Rules:
- Rule 1C: When the DBM (default binding mode) is not `move` (whether or not behind a reference), writing `mut`, `ref`, or `ref mut` on a binding is an error.
- Rule 2C: Reference patterns can only match against references in the scrutinee when the DBM is `move`.
This minimal version is forward-compatible with the main proposals for match ergonomics 2024: [RFC3627](https://rust-lang.github.io/rfcs/3627-match-ergonomics-2024.html) itself, the alternative [rule 4-early variant](https://rust-lang.github.io/rfcs/3627-match-ergonomics-2024.html), and [others](https://hackmd.io/zUqs2ISNQ0Wrnxsa9nhD0Q). The idea is to give us more time to iron out a final proposal.
This includes a migration lint that desugars any offending pattern into one that doesn't make use of match ergonomics. Such patterns have identical meaning across editions.
This PR insta-stabilizes the proposed behavior onto edition 2024.
r? `@ghost`
Tracking:
- https://github.com/rust-lang/rust/issues/123076
Add the pauth-lr target feature, corresponding to aarch64 FEAT_PAuth_LR.
This feature has been added in LLVM 19.
It is currently not supported by the Linux hwcap and so we cannot add
runtime feature detection for it at this time.
Rollup of 10 pull requests
Successful merges:
- #131582 (Add wasm32-unknown-emscripten platform support document)
- #131694 (Make fuchsia-test-runner.py compatible with new JSON output from llvm-readelf)
- #131700 (Fix match_same_arms in stable_mir)
- #131712 (Mark the unstable LazyCell::into_inner const)
- #131746 (Relax a memory order in `once_box`)
- #131754 (Don't report bivariance error when nesting a struct with field errors into another struct)
- #131760 (llvm: Match aarch64 data layout to new LLVM layout)
- #131764 (Fix unnecessary nesting in run-make test output directories)
- #131766 (Add mailmap entry for my dev-desktop setup)
- #131771 (Handle gracefully true/false in `cfg(target(..))` compact)
r? `@ghost`
`@rustbot` modify labels: rollup
Handle gracefully true/false in `cfg(target(..))` compact
This PR handles gracefully `true`/`false` in `cfg(target(..))` compact instead of ICE.
r? `@nnethercote`
Fixes#131759
llvm: Match aarch64 data layout to new LLVM layout
LLVM has added 3 new address spaces to support special Windows use cases. These shouldn't trouble us for now, but LLVM requires matching data layouts.
See llvm/llvm-project#111879 for details
Don't report bivariance error when nesting a struct with field errors into another struct
We currently have logic to avoid reporting lifetime bivariance ("lifetime parameter ... is never used") errors when a struct has field resolution errors. However, this doesn't apply transitively. This PR implements a simple visitor to do so.
This was reported [here](https://twitter.com/fasterthanlime/status/1846257921086165033) since a `derive(Deserialize, Serialize)` ends up generating helper structs which have bivariant lifetimes due to containing the offending struct (that's being derived on).
Fix match_same_arms in stable_mir
Hi,
This PR fixes some clippy warnings
(Reopened https://github.com/rust-lang/rust/pull/131688)
```
warning: this match arm has an identical body to another arm
--> compiler/stable_mir/src/mir/visit.rs:197:13
|
197 | / StatementKind::FakeRead(_, place) => {
198 | | self.visit_place(place, PlaceContext::NON_MUTATING, location);
199 | | }
| |_____________^
|
= help: try changing either arm body
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_same_arms
help: or try merging the arm patterns
|
197 | StatementKind::FakeRead(_, place) | StatementKind::PlaceMention(place) => {
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
help: and remove this obsolete arm
|
209 - StatementKind::PlaceMention(place) => {
210 - self.visit_place(place, PlaceContext::NON_MUTATING, location);
211 - }
|
```
Best regards,
Michal
Remove `GenKillAnalysis`
There are two kinds of dataflow analysis in the compiler: `Analysis`, which is the basic kind, and `GenKillAnalysis`, which is a more specialized kind for gen/kill analyses that is intended as an optimization. However, it turns out that `GenKillAnalysis` is actually a pessimization! It's faster (and much simpler) to do all the gen/kill analyses via `Analysis`. This lets us remove `GenKillAnalysis`, and `GenKillSet`, and a few other things, and also merge `AnalysisDomain` into `Analysis`. The PR removes 500 lines of code and improves performance.
r? `@tmiasko`
Use `ThinVec` for PredicateObligation storage
~~I noticed while profiling clippy on a project that a large amount of time is being spent allocating `Vec`s for `PredicateObligation`, and the `Vec`s are often quite small. This is an attempt to optimise this by using SmallVec to avoid heap allocations for these common small Vecs.~~
This PR turns all the `Vec<PredicateObligation>` into a single type alias while avoiding referring to `Vec` around it, then swaps the type over to `ThinVec<PredicateObligation>` and fixes the fallout. This also contains an implementation of `ThinVec::extract_if`, copied from `Vec::extract_if` and currently being upstreamed to https://github.com/Gankra/thin-vec/pull/66.
This leads to a small (0.2-0.7%) performance gain in the latest perf run.
LLVM has added 3 new address spaces to support special Windows use
cases. These shouldn't trouble us for now, but LLVM requires matching
data layouts.
See llvm/llvm-project#111879 for details
Fix uninlined_format_args in stable_mir
Hi,
This PR fixes some clippy warnings
```
warning: variables can be used directly in the `format!` string
--> compiler/stable_mir/src/mir/pretty.rs:362:13
|
362 | write!(writer, "{kind}{:?}", place)
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#uninlined_format_args
= note: requested on the command line with `-W clippy::uninlined-format-args`
help: change this to
|
362 - write!(writer, "{kind}{:?}", place)
362 + write!(writer, "{kind}{place:?}")
|
```
Best regards,
Michal
Don't report `on_unimplemented` message for negative traits
Kinda useless change but it was affecting my ability to read error messages when experimenting with negative bounds.
