Don't require method impls for methods with `Self:Sized` bounds for impls for unsized types
Similarly to how #112319 doesn't require specifying associated types with `Self: Sized` bounds on `dyn Trait`, we now don't require assoc items with `Self: Sized` bounds to be in impls of for unsized types.
Additionally we lint assoc items with `Self: Sized` bounds that are in such impls:
```rust
trait Foo {
fn foo() where Self: Sized;
}
impl Foo for () {
fn foo() {}
}
impl Foo for i32 {}
//~^ ERROR: not all trait items implemented, missing: `foo`
impl Foo for dyn std::fmt::Debug {}
#[deny(dead_code)]
impl Foo for dyn std::fmt::Display {
fn foo() {}
//~^ ERROR this item cannot be used as its where bounds are not satisfied
}
```
Note that this works with the same `Self: Sized` specific logic we already have for `dyn Trait`, so no new capabilities like avoiding assoc items with `Self: Copy` bounds on impls for `String` or such are added here. Specifying `where ConcreteType: Sized` in a trait and implementing the trait for `ConcreteType` also does not work, it *must* be exactly `Self: Sized`.
remove `simd_fpow` and `simd_fpowi`
Discussed in https://github.com/rust-lang/rust/issues/137555
These functions are not exposed from `std::intrinsics::simd`, and not used anywhere outside of the compiler. They also don't lower to particularly good code at least on the major ISAs (I checked x86_64, aarch64, s390x, powerpc), where the vector is just spilled to the stack and scalar functions are used for the actual logic.
r? `@RalfJung`
Improve behavior of `IF_LET_RESCOPE` around temporaries and place expressions
Heavily reworks the `IF_LET_RESCOPE` to be more sensitive around 1. temporaries that get consumed/terminated and therefore should not trigger the lint, and 2. borrows of place expressions, which are not temporary values.
Fixes#137411
Make `#[used]` work when linking with `ld64`
To make `#[used]` work in static libraries, we use the `symbols.o` trick introduced in https://github.com/rust-lang/rust/pull/95604.
However, the linker shipped with Xcode, ld64, works a bit differently from other linkers; in particular, [it completely ignores undefined symbols by themselves](https://github.com/apple-oss-distributions/ld64/blob/ld64-954.16/src/ld/parsers/macho_relocatable_file.cpp#L2455-L2468), and only consider them if they have relocations (something something atoms something fixups, I don't know the details).
So to make the `symbols.o` file work on ld64, we need to actually insert a relocation. That's kinda cumbersome to do though, since the relocation must be valid, and hence must point to a valid piece of machine code, and is hence very architecture-specific.
Fixes https://github.com/rust-lang/rust/issues/133491, see that for investigation.
---
Another option would be to pass `-u _foo` to the final linker invocation. This has the problem that `-u` causes the linker to not be able to dead-strip the symbol, which is undesirable. (If we did this, we would possibly also want to do it by putting the arguments in a file by itself, and passing that file via ``@`,` e.g. ``@undefined_symbols.txt`,` similar to https://github.com/rust-lang/rust/issues/52699, though that [is only supported since Xcode 12](https://developer.apple.com/documentation/xcode-release-notes/xcode-12-release-notes#Linking), and I'm not sure we wanna bump that).
Various other options that are probably all undesirable as they affect link time performance:
- Pass `-all_load` to the linker.
- Pass `-ObjC` to the linker (the Objective-C support in the linker has different code paths that load more of the binary), and instrument the binaries that contain `#[used]` symbols.
- Pass `-force_load` to libraries that contain `#[used]` symbols.
Failed attempt: Embed `-u _foo` in the object file with `LC_LINKER_OPTION`, akin to https://github.com/rust-lang/rust/issues/121293. Doesn't work, both because `ld64` doesn't read that from archive members unless it already has a reason to load the member (which is what this PR is trying to make it do), and because `ld64` only support the `-l`, `-needed-l`, `-framework` and `-needed_framework` flags in there.
---
TODO:
- [x] Support all Apple architectures.
- [x] Ensure that this works regardless of the actual type of the symbol.
- [x] Write up more docs.
- [x] Wire up a few proper tests.
`@rustbot` label O-apple
Don't immediately panic if dropck fails without returning errors
This span_bug was a little too optimistic. I've decided that matching on the ErrorGuaranteed is a little more sensible than a delay bug that will always be ignored.
closes#137329
r? `@compiler-errors`
remove `#[rustc_intrinsic_must_be_overridde]`
In https://github.com/rust-lang/rust/pull/135031, we gained support for just leaving away the body. Now that the bootstrap compiler got bumped, stop using the old style and remove support for it.
r? `@oli-obk`
There are a few more mentions of this attribute in RA code that I didn't touch; Cc `@rust-lang/rust-analyzer`
Consolidate and improve error messaging for `CoerceUnsized` and `DispatchFromDyn`
Firstly, this PR consolidates and reworks the error diagnostics for `CoercePointee` and `DispatchFromDyn`. There was a ton of duplication for no reason -- this reworks both the errors and also the error codes, since they can be shared between both traits since they report the same thing.
Secondly, when encountering a struct with multiple fields that must be coerced, point out the field spans, rather than mentioning the fields by name. This makes the error message clearer, but also means that we don't mention the `__S` dummy parameter for `derive(CoercePointee)`.
Thirdly, emit a custom error message when we encounter a trait error that comes from the recursive field `CoerceUnsized`/`DispatchFromDyn` trait check. **Note:** This is the only one I'm not too satisfied with -- I think it could use some more refinement, but ideally it explains that the field must be an unsize-able pointer... Feedback welcome.
Finally, don't emit `DispatchFromDyn` validity errors if we detect `CoerceUnsized` validity errors from an impl of the same ADT.
This is best reviewed per commit.
r? `@oli-obk` perhaps?
cc `@dingxiangfei2009` -- sorry for making my own attempt at this PR, but I wanted to see if I could implement a fix for #136796 in a less complicated way, since communicating over github review comments can be a bit slow. I'll leave comments inline to explain my thinking about the diagnostics changes.
New attribute parsing infrastructure
Another step in the plan outlined in https://github.com/rust-lang/rust/issues/131229
introduces infrastructure for structured parsers for attributes, as well as converting a couple of complex attributes to have such structured parsers.
This PR may prove too large to review. I left some of my own comments to guide it a little. Some general notes:
- The first commit is basically standalone. It just preps some mostly unrelated sources for the rest of the PR to work. It might not have enormous merit on its own, but not negative merit either. Could be merged alone, but also doesn't make the review a whole lot easier. (but it's only +274 -209)
- The second commit is the one that introduces new infrastructure. It's the important one to review.
- The 3rd commit uses the new infrastructure showing how some of the more complex attributes can be parsed using it. Theoretically can be split up, though the parsers in this commit are the ones that really test the new infrastructure and show that it all works.
- The 4th commit fixes up rustdoc and clippy. In the previous 2 they didn't compile yet while the compiler does. Separated them out to separate concerns and make the rest more palatable.
- The 5th commit blesses some test outputs. Sometimes that's just because a diagnostic happens slightly earlier than before, which I'd say is acceptable. Sometimes a diagnostic is now only emitted once where it would've been twice before (yay! fixed some bugs). One test I actually moved from crashes to fixed, because it simply doesn't crash anymore. That's why this PR Closes#132391. I think most choices I made here are generally reasonable, but let me know if you disagree anywhere.
- The 6th commit adds a derive to pretty print attributes
- The 7th removes smir apis for attributes, for the time being. The api will at some point be replaced by one based on `rustc_ast_data_structures::AttributeKind`
In general, a lot of the additions here are comments. I've found it very important to document new things in the 2nd commit well so other people can start using it.
Closes#132391Closes#136717
Type lowering can give non-fatal errors that dropck then uses to suppress its own errors. Assume this is the cases when we can't find the error in borrowck.
In the standard library, the `Extend` impl for `Iterator` (specialised
with `TrustedLen`) has a parameter which is constrained by a projection
predicate. This projection predicate provides a value for an inference
variable but host effect evaluation wasn't resolving variables first.
Adding the extra resolve can the number of errors in some tests when they
gain host effect predicates, but this is not unexpected as calls to
`resolve_vars_if_possible` can cause more error tainting to happen.
Co-authored-by: Boxy <rust@boxyuwu.dev>
`rustc_codegen_llvm` relied on `Deref` impls where `Deref::Target` was
or contained an extern type - in my experimental implementation of
rust-lang/rfcs#3729, this isn't possible as the `Target` associated
type's `?Sized` bound cannot be relaxed backwards compatibly (unless we
come up with some way of doing this).
In later pull requests with the rust-lang/rfcs#3729 implementation,
breakage like this could only occur for nightly users relying on the
`extern_types` feature.
Upstreaming this to avoid needing to keep carrying this patch locally,
and I think it'll necessarily need to change eventually.
Add a span to `CompilerBuiltinsCannotCall`
Currently, this error emit a diagnostic with no context like:
error: `compiler_builtins` cannot call functions through upstream monomorphizations; encountered invalid call from `<math::libm::support::hex_float::Hexf<i32> as core::fmt::LowerHex>::fmt` to `core::fmt::num::<impl core::fmt::LowerHex for i32>::fmt`
With this change, it at least usually points to the problematic function:
error: `compiler_builtins` cannot call functions through upstream monomorphizations; encountered invalid call from `<math::libm::support::hex_float::Hexf<i32> as core::fmt::LowerHex>::fmt` to `core::fmt::num::<impl core::fmt::LowerHex for i32>::fmt`
--> src/../libm/src/math/support/hex_float.rs:270:5
|
270 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
Allow `IndexSlice` to be indexed by ranges.
This comes with some annoyances as the index type can no longer inferred from indexing expressions. The biggest offender for this is `IndexVec::from_fn_n(|idx| ..., n)` where the index type won't be inferred from the call site or any index expressions inside the closure.
My main use case for this is mapping a `Place` to `Range<Idx>` for value tracking where the range represents all the values the place contains.
Currently, this error emit a diagnostic with no context like:
error: `compiler_builtins` cannot call functions through upstream monomorphizations; encountered invalid call from `<math::libm::support::hex_float::Hexf<i32> as core::fmt::LowerHex>::fmt` to `core::fmt::num::<impl core::fmt::LowerHex for i32>::fmt`
With this change, it at least usually points to the problematic
function:
error: `compiler_builtins` cannot call functions through upstream monomorphizations; encountered invalid call from `<math::libm::support::hex_float::Hexf<i32> as core::fmt::LowerHex>::fmt` to `core::fmt::num::<impl core::fmt::LowerHex for i32>::fmt`
--> src/../libm/src/math/support/hex_float.rs:270:5
|
270 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
Emit getelementptr inbounds nuw for pointer::add()
Lower pointer::add (via intrinsic::offset with unsigned offset) to getelementptr inbounds nuw on LLVM versions that support it. This lets LLVM make use of the pre-condition that the offset addition does not wrap in an unsigned sense. Together with inbounds, this also implies that the offset is non-negative.
Fixes https://github.com/rust-lang/rust/issues/137217.
FIx `sym` -> `syn` typo in tail-expr-drop-order type opt-out
The #131326 PR attempts to reduce some false positives for the `tail_expr_drop_order` lint by hard-coding some common ecosystem crate names. Specifically, I believe it attempts to opt out the drop impls from `syn` which only exist as optimizations.
However, this was typo'd like "sym", which is a crate that has been [yanked](https://crates.io/crates/sym) (lol). This PR fixes that.
cc `@dingxiangfei2009` `@nikomatsakis` -- did I mistake this? Was this meant to be a different crate?
`@bors` rollup
intrinsics: unify rint, roundeven, nearbyint in a single round_ties_even intrinsic
LLVM has three intrinsics here that all do the same thing (when used in the default FP environment). There's no reason Rust needs to copy that historically-grown mess -- let's just have one intrinsic and leave it up to the LLVM backend to decide how to lower that.
Suggested by `@hanna-kruppe` in https://github.com/rust-lang/rust/issues/136459; Cc `@tgross35`
try-job: test-various
Misc. `rustc_codegen_ssa` cleanups 🧹
Just a bunch of stuff I found while reading the crate's code.
Each commit can stand on its own.
Maybe r? `@Noratrieb` because I saw you did some similar cleanups on these files a while ago? (feel free to re-assign, I'm just guessing)
vectorcall ABI: require SSE2
According to the official docs at https://learn.microsoft.com/en-us/cpp/cpp/vectorcall, SSE2 is required for this ABI. Add a check that enforces this.
I put this together with the other checks ensuring the target features required for a function are present... however, since the ABI is known pre-monomorphization, it would be possible to do this check earlier, which would have the advantage of checking even in `cargo check`. It would have the disadvantage of spreading this code in yet more places.
The first commit just does a little refactoring of the mono-time ABI check to make it easier to add the new check.
Cc `@workingjubilee`
try-job: dist-i586-gnu-i586-i686-musl
Fix "missing match arm body" suggestion involving `!`
Include the match arm guard in the gated span, so that the suggestion to add a body is correct instead of inserting the body before the guard.
Make the suggestion verbose.
```
error: `match` arm with no body
--> $DIR/feature-gate-never_patterns.rs:43:9
|
LL | Some(_) if false,
| ^^^^^^^^^^^^^^^^
|
help: add a body after the pattern
|
LL | Some(_) if false => { todo!() },
| ++++++++++++++
```
r? `@compiler-errors`
Improve a bit HIR pretty printer
This PR improve (a bit) the HIR pretty printer.
It does so by:
- Not printing elided lifetimes (those are not expressible in surface Rust anyway)
- And by rendering implicit self with the shorthand syntax
I also tried fixing some indentation and other things but gave up for now.
Best reviewed commit by commit.
Greatly simplify lifetime captures in edition 2024
Remove most of the `+ Captures` and `+ '_` from the compiler, since they are now unnecessary with the new edition 2021 lifetime capture rules. Use some `+ 'tcx` and `+ 'static` rather than being overly verbose with precise capturing syntax.
Remove invalid suggestion of into_iter for extern macro
Fixes#137345#109082 is closed due to performance issue, do we have any other solution for this kind of issue?
compiler: untangle SIMD alignment assumptions
There were a number of puzzling assumptions being made about SIMD types and their layout that I have corrected in this diff. These are mostly no-op edits in actual fact, but they do subtly alter a pair of checks in our invariant-checking and union layout computation that rested on those peculiar assumptions. Those unfortunately stand in the way of any further actual fixes. I submit this for review, even though it's not clearly motivated without its followups, because it should still be possible to independently conclude whether this is correct.
Give `global_asm` a fake body to store typeck results, represent `sym fn` as a hir expr to fix `sym fn` operands with lifetimes
There are a few intertwined problems with `sym fn` operands in both inline and global asm macros.
Specifically, unlike other anon consts, they may evaluate to a type with free regions in them without actually having an item-level type annotation to give them a "proper" type. This is in contrast to named constants, which always have an item-level type annotation, or unnamed constants which are constrained by their position (e.g. a const arg in a turbofish, or a const array length).
Today, we infer the type of the operand by looking at the HIR typeck results; however, those results are region-erased, so during borrowck we ICE since we don't expect to encounter erased regions. We can't just fill this type with something like `'static`, since we may want to use real (free) regions:
```rust
fn foo<'a>() {
asm!("/* ... */", sym bar::<&'a ()>);
}
```
The first idea may be to represent `sym fn` operands using *inline* consts instead of anon consts. This makes sense, since inline consts can reference regions from the parent body (like the `'a` in the example above). However, this introduces a problem with `global_asm!`, which doesn't *have* a parent body; inline consts *must* be associated with a parent body since they are not a body owner of their own. In #116087, I attempted to fix this by using two separate `sym` operands for global and inline asm. However, this led to a lot of confusion and also some unattractive code duplication.
In this PR, I adjust the lowering of `global_asm!` so that it's lowered in a "fake" HIR body. This body contains a single expression which is `ExprKind::InlineAsm`; we don't *use* this HIR body, but it's used in typeck and borrowck so that we can properly infer and validate the the lifetimes of `sym fn` operands.
I then adjust the lowering of `sym fn` to instead be represented with a HIR expression. This is both because it's no longer necessary to represent this operand as an anon const, since it's *just* a path expression, and also more importantly to sidestep yet another ICE (https://github.com/rust-lang/rust/issues/137179), which has to do with the existing code breaking an invariant of def-id creation and anon consts. Specifically, we are not allowed to synthesize a def-id for an anon const when that anon const contains expressions with def-ids whose parent is *not* that anon const. This is somewhat related to https://github.com/rust-lang/rust/pull/130443#issuecomment-2445678945, which is also a place in the compiler where synthesizing anon consts leads to def-id parenting issue.
As a side-effect, this consolidates the type checking for inline and global asm, so it allows us to simplify `InlineAsmCtxt` a bit. It also allows us to delete a bit of hacky code from anon const `type_of` which was there to detect `sym fn` operands specifically. This also could be generalized to support `const` asm operands with types with lifetimes in them. Since we specifically reject these consts today, I'm not going to change the representation of those consts (but they'd just be turned into inline consts).
r? oli-obk -- mostly b/c you're patient and also understand the breadth of the code that this touches, please reassign if you don't want to review this.
Fixes#111709Fixes#96304Fixes#137179
Inject `compiler_builtins` during postprocessing and ensure it is made private
Follow up of https://github.com/rust-lang/rust/pull/135278
Do the following:
* Inject `compiler_builtins` during postprocessing, rather than injecting `extern crate compiler_builtins as _` into the AST
* Do not make dependencies of `std` private by default (this was added in #135278)
* Make sure sysroot crates correctly mark their dependencies private/public
* Ensure that marking a dependency private makes its dependents private by default as well, unless otherwise specified
* Do the `compiler_builtins` update that has been blocked on this
There is more detail in the commit messages. This includes the changes I was working on in https://github.com/rust-lang/rust/pull/136226.
try-job: test-various
try-job: x86_64-msvc-1
try-job: x86_64-msvc-2
try-job: i686-mingw-1
try-job: i686-mingw-2
In Rust 1.81, we added a FCW lint (including linting in dependencies)
against pointer casts that add an auto trait to dyn bounds. This was
part of work making casts of pointers involving trait objects stricter
which was needed to restabilize trait upcasting.
We considered just making this a hard error at the time, but opted
against it due to breakage found by crater. This breakage was mostly
due to the `anymap` crate which has been a persistent problem for us.
It's now a year later, and the fact that this is not yet a hard error
is giving us pause about stabilizing arbitrary self types and
`derive(CoercePointee)`. So let's now make a hard error of this.
Include the match arm guard in the gated span, so that the suggestion to add a body is correct instead of inserting the body before the guard.
Make the suggestion verbose.
```
error: `match` arm with no body
--> $DIR/feature-gate-never_patterns.rs:43:9
|
LL | Some(_) if false,
| ^^^^^^^^^^^^^^^^
|
help: add a body after the pattern
|
LL | Some(_) if false => { todo!() },
| ++++++++++++++
```
Use StableHasher + Hash64 for dep_tracking_hash
This is similar to https://github.com/rust-lang/rust/pull/137095. We currently have a +/- 1 byte jitter in the size of dep graphs reported on perf.rust-lang.org. I think this fixes that jitter.
When I introduced `Hash64`, I wired it through most of the compiler by making it an output of `StableHasher::finalize` then fixing the compile errors. I missed this case because the `u64` hash in this function is being produced by `DefaultHasher` instead. That seems pretty sketchy because the code seems confident that the hash needs to be stable, and we have a mechanism for stable hashing that we weren't using here.
Always allow reusing cratenum in CrateLoader::load
The only case where can_reuse_cratenum could have been false in the past are rustc plugins, support for which has been removed over a year ago now. Nowadays the only case where locator.tuple is not target_triple is when loading a proc macro, in which case we also set can_reuse_cratenum to true. As such it is always true and we can remove some dead code.
Ferris 🦀 Identifier naming conventions
You cannot use Ferris as an identifier in Rust, this code will suggest to correct the 🦀 to `ferris`:
```rs
fn main() {
let 🦀 = 4;
}
```
But it also suggests to correct to `ferris` in these cases, too:
```rs
struct 🦀 {}
fn main() {}
```
^ suggests: `ferris`
~ with this PR: `Ferris`
```rs
static 🦀: &str = "ferris!";
fn main() {}
```
^ suggests: `ferris`
~ with this PR: `FERRIS`
This is my first pull requests here!
Use `edition = "2024"` in the compiler (redux)
Most of this is binding mode changes, which I fixed by running `x.py fix`.
Also adds some miscellaneous `unsafe` blocks for new unsafe standard library functions (the setenv ones), and a missing `unsafe extern` block in some enzyme codegen code, and fixes some precise capturing lifetime changes (but only when they led to errors).
cc ``@ehuss`` ``@traviscross``
Prune dead regionck code
We never encounter `ObligationCauseCode`s that correspond to region obligations that originate from "within" a body, since we don't do HIR regionck anymore on bodies. So prune some dead code.
test building enzyme in CI
1) This PR fixes a significant compile-time regression, by only running the expensive autodiff pipeline, if the users pass the newly introduced Enable value to the `-Zautodiff=` flag. It updates the test(s) accordingly. It gives a nice error if users forget that.
2) It fixes macos support by explicitly linking against the Enzyme build folder. This doesn't cover CI macos yet.
3) It fixes the issue that setting ENZYME_RUNPASS was ignored by enzyme and in fact did not schedule enzyme's opt pass.
4) It also re-enables support for various other values for the autodiff flag, which were ignored since the refactor.
5) I merged some improvements to Enzyme core, which means we do not longer depend on LLVM being build with the Plugin Interface enabled.
6) Unrelated to other fixes, this changes `rustc_autodiff` to `EncodeCrossCrate::Yes`. It is not enough on it's own to enable usage of Enzyme in libraries, but it is for sure a piece of the fixes needed to get this to work.
try-job: x86_64-gnu
r? `@oli-obk`
Tracking:
- https://github.com/rust-lang/rust/issues/124509
Remove `NtVis` and `NtTy`
The next part of #124141. The first actual remove of `Nonterminal` variants. `NtVis` is a simple case that doesn't get much use, but `NtTy` is more complex.
r? `@petrochenkov`
Rollup of 8 pull requests
Successful merges:
- #136458 (Do not deduplicate list of associated types provided by dyn principal)
- #136474 ([`compiletest`-related cleanups 3/7] Make the distinction between sources root vs test suite sources root in compiletest less confusing)
- #136592 (Make sure we don't overrun the stack in canonicalizer)
- #136787 (Remove `lifetime_capture_rules_2024` feature)
- #137207 (Add #[track_caller] to Duration Div impl)
- #137245 (Tweak E0277 when predicate comes indirectly from ?)
- #137257 (Ignore fake borrows for packed field check)
- #137399 (fix ICE in layout computation with unnormalizable const)
r? `@ghost`
`@rustbot` modify labels: rollup
fix ICE in layout computation with unnormalizable const
The first commit reverts half of 7a667d206c, where I removed a case from `layout_of` for handling non-generic unevaluated consts in array length, that I incorrectly assumed to be unreachable. This can actually happen with the combination of `feature(generic_const_exprs)` and `feature(trivial_bounds)`, because GCE makes anon consts inherit their parent's predicates and with an impossible predicate like `u8: A` it's possible to have an array whose length is an associated const like `<u8 as A>::B` that is not generic, but also can't be normalized:
```rust
#![feature(generic_const_exprs)]
#![feature(trivial_bounds)]
trait A {
const B: usize;
}
// With GCE + trivial bounds this definition is not a compile error.
// Computing the layout of this type shouldn't ICE.
struct S([u8; <u8 as A>::B])
where
u8: A;
```
---
The first commit also incidentally fixes https://github.com/rust-lang/rust/issues/137308, which also managed to get an unnormalizable assoc const into an array length:
```rust
trait A {
const B: usize;
}
impl<C: ?Sized> A for u8 { //~ ERROR: the type parameter `C` is not constrained
const B: usize = 42;
}
// Computing the layout of this type shouldn't ICE, even with the compile error above.
struct S([u8; <u8 as A>::B]);
```
This happens, because we bail out from `codegen_select_candidate` with an error if the selected impl has unconstrained params to avoid leaking infer vars out of a query. `Instance::try_resolve` will then return `Ok(None)`, which for assoc consts roughly means "this const can't be evaluated in a generic context" and is treated as such: 71e06b9c59/compiler/rustc_middle/src/mir/interpret/queries.rs (L84) (and this can ICE if the const isn't generic: https://github.com/rust-lang/rust/issues/135617).
However, here `<u8 as A>::B` is definitely not "too generic" and also not unresolvable due to an unsatisfiable `u8: A` bound, so I've included the second commit to change the result of `Instance::try_resolve` from `Ok(None)` to `Err(ErrorGuaranteed)` when resolving an assoc item to an impl with unconstrained generic params. This has the effect that `<u8 as A>::B` will now be normalized to `ConstKind::Error` in the example above.
This properly fixes https://github.com/rust-lang/rust/issues/137308, by no longer treating `<u8 as A>::B` as unresolvable even though it clearly has a unique impl that it resolves to. It also has the effect of changing the layout error from `Unknown` ("the type may be valid but has no sensible layout") to `ReferencesError` ("a non-layout error is reported elsewhere") which seems more appropriate.
r? ```@compiler-errors```
Ignore fake borrows for packed field check
We should not emit unaligned packed field reference errors for the fake borrows that we generate during match lowering.
These fake borrows are there to ensure in *borrow-checking* that we don't modify the value being matched (which is why this only occurs when there's a match guard, in this case `if true`), but they are removed after the MIR is processed by `CleanupPostBorrowck`, since they're really just there to cause borrowck errors if necessary.
I modified `PlaceContext::is_borrow` since that's used by the packed field check:
17c1c329a5/compiler/rustc_mir_transform/src/check_packed_ref.rs (L40)
It's only used in one other place, in the SROA optimization (by which fake borrows are removed, so it doesn't matter):
17c1c329a5/compiler/rustc_mir_dataflow/src/value_analysis.rs (L922)
Fixes https://github.com/rust-lang/rust/issues/137250
Tweak E0277 when predicate comes indirectly from ?
When a `?` operation requires an `Into` conversion with additional bounds (like having a concrete error but wanting to convert to a trait object), we handle it speficically and provide the same kind of information we give other `?` related errors.
```
error[E0277]: `?` couldn't convert the error: `E: std::error::Error` is not satisfied
--> $DIR/bad-question-mark-on-trait-object.rs:7:13
|
LL | fn foo() -> Result<(), Box<dyn std::error::Error>> {
| -------------------------------------- required `E: std::error::Error` because of this
LL | Ok(bar()?)
| -----^ the trait `std::error::Error` is not implemented for `E`
| |
| this has type `Result<_, E>`
|
note: `E` needs to implement `std::error::Error`
--> $DIR/bad-question-mark-on-trait-object.rs:1:1
|
LL | struct E;
| ^^^^^^^^
= note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait
= note: required for `Box<dyn std::error::Error>` to implement `From<E>`
```
Avoid talking about `FromResidual` when other more relevant information is being given, particularly from `rust_on_unimplemented`.
Fix#137238.
-----
CC #137232, which was a smaller step related to this.
Do not deduplicate list of associated types provided by dyn principal
## Background
The way that we handle a dyn trait type's projection bounds is very *structural* today. A dyn trait is represented as a list of `PolyExistentialPredicate`s, which in most cases will be a principal trait (like `Iterator`) and a list of projections (like `Item = u32`). Importantly, the list of projections comes from user-written associated type bounds on the type *and* from elaborating the projections from the principal's supertraits.
For example, given a set of traits like:
```rust
trait Foo<T> {
type Assoc;
}
trait Bar<A, B>: Foo<A, Assoc = A> + Foo<B, Assoc = B> {}
```
For the type `dyn Bar<i32, u32>`, the list of projections will be something like `[Foo<i32>::Assoc = i32, Foo<u32>::Assoc = u32]`. We deduplicate these projections when they're identical, so for `dyn Bar<(), ()>` would be something like `[Foo<()>::Assoc = ()]`.
## Shortcomings 1: inference
We face problems when we begin to mix this structural notion of projection bounds with inference and associated type normalization. For example, let's try calling a generic function that takes `dyn Bar<A, B>` with a value of type `dyn Bar<(), ()>`:
```rust
trait Foo<T> {
type Assoc;
}
trait Bar<A, B>: Foo<A, Assoc = A> + Foo<B, Assoc = B> {}
fn call_bar<A, B>(_: &dyn Bar<A, B>) {}
fn test(x: &dyn Bar<(), ()>) {
call_bar(x);
// ^ ERROR mismatched types
}
```
```
error[E0308]: mismatched types
--> /home/mgx/test.rs:10:14
|
10 | call_bar(x);
| -------- ^ expected trait `Bar<_, _>`, found trait `Bar<(), ()>`
```
What's going on here? Well, when calling `call_bar`, the generic signature `&dyn Bar<?A, ?B>` does not unify with `&dyn Bar<(), ()>` because the list of projections differ -- `[Foo<?A>::Assoc = ?A, Foo<?B>::Assoc = ?B]` vs `[Foo<()>::Assoc = ()]`.
A simple solution to this may be to unify the principal traits first, then attempt to deduplicate them after inference. In this case, if we constrain `?A = ?B = ()`, then we would be able to deduplicate those projections in the first list.
However, this idea is still pretty fragile, and it's not a complete solution.
## Shortcomings 2: normalization
Consider a slightly modified example:
```rust
//@ compile-flags: -Znext-solver
trait Mirror {
type Assoc;
}
impl<T> Mirror for T {
type Assoc = T;
}
fn call_bar(_: &dyn Bar<(), <() as Mirror>::Assoc>) {}
fn test(x: &dyn Bar<(), ()>) {
call_bar(x);
}
```
This fails in the new solver. In this example, we try to unify `dyn Bar<(), ()>` and `dyn Bar<(), <() as Mirror>::Assoc>`. We are faced with the same problem even though there are no inference variables, and making this work relies on eagerly and deeply normalizing all projections so that they can be structurally deduplicated.
This is incompatible with how we handle associated types in the new trait solver, and while we could perhaps support it with some major gymnastics in the new solver, it suggests more fundamental shortcomings with how we deal with projection bounds in the new solver.
## Shortcomings 3: redundant projections
Consider a final example:
```rust
trait Foo {
type Assoc;
}
trait Bar: Foo<Assoc = ()> {}
fn call_bar1(_: &dyn Bar) {}
fn call_bar2(_: &dyn Bar<Assoc = ()>) {}
fn main() {
let x: &dyn Bar<Assoc = _> = todo!();
call_bar1(x);
//~^ ERROR mismatched types
call_bar2(x);
//~^ ERROR mismatched types
}
```
In this case, we have a user-written associated type bound (`Assoc = _`) which overlaps the bound that comes from the supertrait projection of `Bar` (namely, `Foo<Assoc = ()>`). In a similar way to the two examples above, this causes us to have a projection list mismatch that the compiler is not able to deduplicate.
## Solution
### Do not deduplicate after elaborating projections when lowering `dyn` types
The root cause of this issue has to do with mismatches of the deduplicated projection list before and after substitution or inference. This PR aims to avoid these issues by *never* deduplicating the projection list after elaborating the list of projections from the *identity* substituted principal trait ref.
For example,
```rust
trait Foo<T> {
type Assoc;
}
trait Bar<A, B>: Foo<A, Assoc = A> + Foo<B, Assoc = B> {}
```
When computing the projections for `dyn Bar<(), ()>`, before this PR we'd elaborate `Bar<(), ()>` to find a (deduplicated) projection list of `[Foo<()>::Assoc = ()]`.
After this PR, we take the principal trait and use its *identity* substitutions `Bar<A, B>` during elaboration, giving us projections `[Foo<A>::Assoc = A, Foo<B>::Assoc = B]`. Only after this elaboration do we substitute `A = (), B = ()` to get `[Foo<()>::Assoc = (), Foo<()>::Assoc = ()]`. This allows the type to be unified with the projections for `dyn Bar<?A, ?B>`, which are `[Foo<?A>::Assoc = ?A, Foo<?B>::Assoc = ?B]`.
This helps us avoid shorcomings 1 noted above.
### Do not deduplicate projections when relating `dyn` types
Similarly, we also do not call deduplicate when relating dyn types. This means that the list of projections does not differ depending on if the type has been normalized or not, which should avoid shortcomings 2 noted above.
Following from the example above, when relating projection lists like `[Foo<()>::Assoc = (), Foo<()>::Assoc = ()]` and `[Foo<?A>::Assoc = ?A, Foo<?B>::Assoc = ?B]`, the latter won't be deduplicated to a list of length 1 which would immediately fail to relate to the latter which is a list of length 2.
### Implement proper precedence between supertrait and user-written projection bounds when lowering `dyn` types
```rust
trait Foo {
type Assoc;
}
trait Bar: Foo<Assoc = ()> {}
```
Given a type like `dyn Foo<Assoc = _>`, we used to previously include *both* the supertrait and user-written associated type bounds in the projection list, giving us `[Foo::Assoc = (), Foo::Assoc = _]`. This would never unify with `dyn Foo`. However, this PR implements a strategy which overwrites the supertrait associated type bound with the one provided by the user, giving us a projection list of `[Foo::Assoc = _]`.
Why is this OK? Well, if a user wrote an associated type bound that is unsatisfiable (e.g. `dyn Bar<Assoc = i32>`) then the dyn type would never implement `Bar` or `Foo` anyways. If the user wrote something that is either structurally equal or equal modulo normalization to the supertrait bound, then it should be unaffected. And if the user wrote something that needs inference guidance (e.g. `dyn Bar<Assoc = _>`), then it'll be constrained when proving `dyn Bar<Assoc = _>: Bar`.
Importantly, this differs from the strategy in https://github.com/rust-lang/rust/pull/133397, which preferred the *supertrait* bound and ignored the user-written bound. While that's also theoretically justifiable in its own way, it does lead to code which does not (and probably should not) compile either today or after this PR, like:
```rust
trait IteratorOfUnit: Iterator<Item = ()> {}
impl<T> IteratorOfUnit for T where T: Iterator<Item = ()> {}
fn main() {
let iter = [()].into_iter();
let iter: &dyn IteratorOfUnit<Item = i32> = &iter;
}
```
### Conclusion
This is a far less invasive change compared to #133397, and doesn't necessarily necessitate the addition of new lints or any breakage of existing code. While we could (and possibly should) eventually introduce lints to warn users of redundant or mismatched associated type bounds, we don't *need* to do so as part of fixing this unsoundness, which leads me to believe this is a much safer solution.
More sophisticated span trimming for suggestions
Previously #136958 only cared about prefixes or suffixes. Now it detects more cases where a suggestion is "sandwiched" by unchanged code on the left or the right. Would be cool if we could detect several insertions, like `ACE` going to `ABCDE`, extracting `B` and `D`, but that seems unwieldy.
r? `@estebank`
```
error[E0277]: `?` couldn't convert the error: `E: std::error::Error` is not satisfied
--> $DIR/bad-question-mark-on-trait-object.rs:7:13
|
LL | fn foo() -> Result<(), Box<dyn std::error::Error>> {
| -------------------------------------- required `E: std::error::Error` because of this
LL | Ok(bar()?)
| -----^ the trait `std::error::Error` is not implemented for `E`
| |
| this has type `Result<_, E>`
|
note: `E` needs to implement `std::error::Error`
--> $DIR/bad-question-mark-on-trait-object.rs:1:1
|
LL | struct E;
| ^^^^^^^^
= note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait
= note: required for `Box<dyn std::error::Error>` to implement `From<E>`
error[E0277]: `?` couldn't convert the error to `X`
--> $DIR/bad-question-mark-on-trait-object.rs:18:13
|
LL | fn bat() -> Result<(), X> {
| ------------- expected `X` because of this
LL | Ok(bar()?)
| -----^ the trait `From<E>` is not implemented for `X`
| |
| this can't be annotated with `?` because it has type `Result<_, E>`
|
note: `X` needs to implement `From<E>`
--> $DIR/bad-question-mark-on-trait-object.rs:4:1
|
LL | struct X;
| ^^^^^^^^
note: alternatively, `E` needs to implement `Into<X>`
--> $DIR/bad-question-mark-on-trait-object.rs:1:1
|
LL | struct E;
| ^^^^^^^^
= note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait
```
Refactor `OperandRef::extract_field` to prep for MCP838
cc https://github.com/rust-lang/compiler-team/issues/838
This still supports exactly the same cases as it did before, just rearranged a bit to better emphasize what doesn't work.
Currently, marking a dependency private does not automatically make all
its child dependencies private. Resolve this by making its children
private by default as well.
This also resolves some FIXMEs for tests that are intended to fail but
previously passed.
[1]: https://github.com/rust-lang/rust/pull/135501#issuecomment-2620242419
In [1], most dependencies of `std` and other sysroot crates were marked
private, but this did not happen for `alloc` and `test`. Update these
here, marking public standard library crates as the only non-private
dependencies.
[1]: https://github.com/rust-lang/rust/pull/111076
Remove the portion of ed63539282 that automatically sets crates private
based on whether they are dependencies of `std`. Instead, this is
controlled by dependency configuration in `Cargo.toml`.
`compiler_builtins` is currently injected as `extern crate
compiler_builtins as _`. This has made gating via diagnostics difficult
because it appears in the crate graph as a non-private dependency, and
there isn't an easy way to differentiate between the injected AST and
user-specified `extern crate compiler_builtins`.
Resolve this by injecting `compiler_builtins` during postprocessing
rather than early in the AST. Most of the time this isn't even needed
because it shows up in `std` or `core`'s crate graph, but injection is
still needed to ensure `#![no_core]` works correctly.
A similar change was attempted at [1] but this encountered errors
building `proc_macro` and `rustc-std-workspace-std`. Similar failures
showed up while working on this patch, which were traced back to
`compiler_builtins` showing up in the graph twice (once via dependency
and once via injection). This is resolved by not injecting if a
`#![compiler_builtins]` crate already exists.
[1]: https://github.com/rust-lang/rust/pull/113634
The only case where can_reuse_cratenum could have been false in the past
are rustc plugins, support for which has been removed over a year ago
now. Nowadays the only case where locator.tuple is not target_triple is
when loading a proc macro, in which case we also set can_reuse_cratenum
to true. As such it is always true and we can remove some dead code.
Some codegen_llvm cleanups
Using some more safe wrappers and thus being able to remove a large unsafe block.
As a next step we should probably look into safe extern fns
Use a probe to avoid registering stray region obligations when re-checking drops in MIR typeck
Fixes#137288.
See the comment I left on the probe. I'm not totally sure why this depends on *both* an unconstrained type parameter in the impl and a type error for the self type, but I think the fix is at least theoretically well motivated.
r? ```@matthewjasper```
Simplify `Postorder` customization.
`Postorder` has a `C: Customization<'tcx>` parameter, that gives it flexibility about how it computes successors. But in practice, there are only two `impls` of `Customization`, and one is for the unit type.
This commit simplifies things by removing the generic parameter and replacing it with an `Option`.
r? ````@saethlin````
add more `s390x` target features
Closes#88937
tracking issue: https://github.com/rust-lang/rust/issues/130869
The target feature names are, right now, just the llvm target feature names. These mostly line up well with the names of [Facility Indications](https://publibfp.dhe.ibm.com/epubs/pdf/a227832d.pdf#page=301) names. The linux kernel (and `/proc/cpuinfo`) uses shorter, more cryptic names. (e.g. "vector" is `vx`). We can deviate from the llvm names, but the CPU vendor (IBM) does not appear to use e.g. `vx` for what they call `vector`.
There are a number of implied target features between the vector facilities (based on the [Facility Indications](https://publibfp.dhe.ibm.com/epubs/pdf/a227832d.pdf#page=301) table):
- 129 The vector facility for z/Architecture is installed in the z/Architecture architectural mode.
- 134 The vector packed decimal facility is installed in the z/Architecture architectural mode. When bit 134 is one, bit 129 is also one.
- 135 The vector enhancements facility 1 is installed in the z/Architecture architectural mode. When bit 135 is one, bit 129 is also one.
- 148 The vector-enhancements facility 2 is installed in the z/Architecture architectural mode. When bit 148 is one, bits 129 and 135 are also one.
- 152 The vector-packed-decimal-enhancement facility 1 is installed in the z/Architecture architectural mode. When bit 152 is one, bits 129 and 134 are also one.
- 165 The neural-network-processing-assist facility is installed in the z/Architecture architectural mode. When bit 165 is one, bit 129 is also one.
- 192 The vector-packed-decimal-enhancement facility 2 is installed in the z/Architecture architectural mode. When bit 192 is one, bits 129, 134, and 152 are also one.
The remaining facilities do not have any implied target features (that we provide):
- 45 The distinct-operands, fast-BCR-serialization, high-word, and population-count facilities, the interlocked-access facility 1, and the load/store-oncondition facility 1 are installed in the z/Architecture architectural mode.
- 73 The transactional-execution facility is installed in the z/Architecture architectural mode. Bit 49 is one when bit 73 is one.
- 133 The guarded-storage facility is installed in the z/Architecture architectural mode.
- 150 The enhanced-sort facility is installed in the z/Architecture architectural mode.
- 151 The DEFLATE-conversion facility is installed in the z/Architecture architectural mode.
The added target features are those that have ISA implications, can be queried at runtime, and have LLVM support. LLVM [defines more target features](d49a2d2bc9/llvm/lib/Target/SystemZ/SystemZFeatures.td), but I'm not sure those are useful. They can always be added later, and can already be set globally using `-Ctarget-feature`.
I'll also update the `is_s390x_feature_supported` macro (added in https://github.com/rust-lang/stdarch/pull/1699, not yet on nightly, that needs an stdarch sync) to include these target features.
``@Amanieu`` you had some reservations about the `"vector"` target feature name. It does appear to be the most "official" name we have. On the one hand the name is very generic, and some of the other names are rather long. For the `neural-network-processing-assist` even LLVM thought that was a bit much and shortened it to `nnp-assist`. Also for `vector-packed-decimal-enhancement facility 1` the llvm naming is inconsistent. On the other hand, the cpuinfo names are very cryptic, and aren't found in the IBM documentation.
r? ``@Amanieu``
cc ``@uweigand`` ``@taiki-e``
Specify scope in `out_of_scope_macro_calls` lint
```
warning: cannot find macro `in_root` in the crate root
--> $DIR/key-value-expansion-scope.rs:1:10
|
LL | #![doc = in_root!()]
| ^^^^^^^ not found in the crate root
|
= warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
= note: for more information, see issue #124535 <https://github.com/rust-lang/rust/issues/124535>
= help: import `macro_rules` with `use` to make it callable above its definition
= note: `#[warn(out_of_scope_macro_calls)]` on by default
```
r? ```@petrochenkov```
Notes about tests:
- tests/ui/parser/macro/trait-object-macro-matcher.rs: the syntax error
is duplicated, because it occurs now when parsing the decl macro
input, and also when parsing the expanded decl macro. But this won't
show up for normal users due to error de-duplication.
- tests/ui/associated-consts/issue-93835.rs: similar, plus there are
some additional errors about this very broken code.
- The changes to metavariable descriptions in #132629 are now visible in
error message for several tests.
This pair of fn was introduced to perform invariant checks for scalars.
Their current behavior doesn't mesh as well with checking SIMD types,
so change the name of the fn to reflect their actual use-case and
refactor the corresponding checks.
Also simplify the returns from Option<AbiAndPrefAlign> to Option<Align>,
because every site was mapping away the "preferred" alignment anyways.
The target feature names are, right now, based on the llvm target feature names. These mostly line up well with the names of [Facility Inidications](https://publibfp.dhe.ibm.com/epubs/pdf/a227832d.pdf#page=301) names. The linux kernel uses shorter, more cryptic names. (e.g. "vector" is `vx`). We can deviate from the llvm names, but the CPU vendor (IBM) does not appear to use e.g. `vx` for what they call `vector`.
There are a number of implied target features between the vector facilities (based on the [Facility Inidications](https://publibfp.dhe.ibm.com/epubs/pdf/a227832d.pdf#page=301) table):
- 129 The vector facility for z/Architecture is installed in the z/Architecture architectural mode.
- 134 The vector packed decimal facility is installed in the z/Architecture architectural mode. When bit 134 is one, bit 129 is also one.
- 135 The vector enhancements facility 1 is installed in the z/Architecture architectural mode. When bit 135 is one, bit 129 is also one.
- 148 The vector-enhancements facility 2 is installed in the z/Architecture architectural mode. When bit 148 is one, bits 129 and 135 are also one.
- 152 The vector-packed-decimal-enhancement facility 1 is installed in the z/Architecture architectural mode. When bit 152 is one, bits 129 and 134 are also one.
- 165 The neural-network-processing-assist facility is installed in the z/Architecture architectural mode. When bit 165 is one, bit 129 is also one.
- 192 The vector-packed-decimal-enhancement facility 2 is installed in the z/Architecture architectural mode. When bit 192 is one, bits 129, 134, and 152 are also one.
And then there are a number of facilities without any implied target features
- 45 The distinct-operands, fast-BCR-serialization, high-word, and population-count facilities, the interlocked-access facility 1, and the load/store-oncondition facility 1 are installed in the z/Architecture architectural mode.
- 73 The transactional-execution facility is installed in the z/Architecture architectural mode. Bit 49 is one when bit 73 is one.
- 133 The guarded-storage facility is installed in the z/Architecture architectural mode.
- 150 The enhanced-sort facility is installed in the z/Architecture architectural mode.
- 151 The DEFLATE-conversion facility is installed in the z/Architecture architectural mode.
The added target features are those that have ISA implications, can be queried at runtime, and have LLVM support. LLVM [defines more target features](d49a2d2bc9/llvm/lib/Target/SystemZ/SystemZFeatures.td), but I'm not sure those are useful. They can always be added later, and can already be set globally using `-Ctarget-feature`.
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`
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)].
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`.
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
The comments didn't make much sense to me. I asked Matthew Jasper on
Zulip about it and they said:
> I think that at the time I wanted to replace all (or most of) this
> with a reference to the HIR Id of the variable. I'll give this a look
> to see if it's still a reasonable idea, but removing the comments is
> fine.
and then:
> I don't think that changing this to an HirId would be better,
> recovering the information from the HIR seems like too much effort in
> exchange for making the MIR a little smaller.
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
This updates the Fuchsia target spec with the [Clang Fuchsia driver],
which picks up a few changes:
* Adds `-z start-stop-visibility=hidden` and `-z rel` to the pre link
arguments.
* Adds `--execute-only` and `--fix-cortex-a53-843419` for
`aarch64-unknown-fuchsia`.
* Enables the cpu features equivalent to x86-64-v2 for
`x86_64-unknown-fuchsia`, which is our minimum supported x86_64.
platform according to [RFC-0073].
* Enables the cpu features `+crc,+aes,+sha2,+neon` on aarch64.
* Increases the max atomic width on 86_64 to 128.
* Enables stack probes and xray on aarch64 and riscv64.
[Clang Fuchsia driver]: 8374d42186/clang/lib/Driver/ToolChains/Fuchsia.cpp
[RFC-0073]: https://fuchsia.dev/fuchsia-src/contribute/governance/rfcs/0073_x86_64_platform_requirement
When a `?` operation requires an `Into` conversion with additional bounds (like having a concrete error but wanting to convert to a trait object), we handle it speficically and provide the same kind of information we give other `?` related errors.
```
error[E0277]: `?` couldn't convert the error: `E: std::error::Error` is not satisfied
--> $DIR/bad-question-mark-on-trait-object.rs:5:13
|
LL | fn foo() -> Result<(), Box<dyn std::error::Error>> {
| -------------------------------------- required `E: std::error::Error` because of this
LL | Ok(bar()?)
| ^ the trait `std::error::Error` is not implemented for `E`
|
= note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait
= note: required for `Box<dyn std::error::Error>` to implement `From<E>`
```
Avoid talking about `FromResidual` when other more relevant information is being given, particularly from `rust_on_unimplemented`.
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
I had to do a lot of debug by printing; having these `Debug` traits in
place made it easier. Additionally, add some more information to
existing `info!` statements.
Introduce an enum that represents the different possible sources for
dependencies, and use them where possible. This will enable more fine
grained control and provides better context than passing the `dep_root`
tuple.
Use this to ensure that injected crates always show up as private by
default.
`Postorder` has a `C: Customization<'tcx>` parameter, that gives it
flexibility about how it computes successors. But in practice, there are
only two `impls` of `Customization`, and one is for the unit type.
This commit simplifies things by removing the generic parameter and
replacing it with an `Option`.
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`
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
The only visible change is to the filenames produce by `-Zdump-mir`.
E.g. before and after:
```
h.main.003-000.analysis-post-cleanup.after.mir
h.main.2-2-000.analysis-post-cleanup.after.mir
```
It also fixes a FIXME comment.
Lint `#[must_use]` attributes applied to methods in trait impls
The `#[must_use]` attribute has no effect when applied to methods in trait implementations. This PR adds it to the unused `#[must_use]` lint, and cleans the extra attributes in portable-simd and Clippy.
Suggest replacing `.` with `::` in more error diagnostics.
First commit makes the existing "help: use the path separator to refer to an item" also work when the base is a type alias, not just a trait/module/struct.
The existing unconditional `DefKind::Mod | DefKind::Trait` match arm is changed to a conditional `DefKind::Mod | DefKind::Trait | DefKind::TyAlias` arm that only matches if the `path_sep` suggestion-adding closure succeeds, so as not to stop the later `DefKind::TyAlias`-specific suggestions if the path-sep suggestion does not apply. This shouldn't change behavior for `Mod` or `Trait` (due to the default arm's `return false` etc).
This commit also updates `tests/ui/resolve/issue-22692.rs` to reflect this, and also renames it to something more meaningful.
This commit also makes the `bad_struct_syntax_suggestion` closure take `err` as a parameter instead of capturing it, since otherwise caused borrowing errors due to the change to using `path_sep` in a pattern guard.
<details> <summary> Type alias diagnostic example </summary>
```rust
type S = String;
fn main() {
let _ = S.new;
}
```
```diff
error[E0423]: expected value, found type alias `S`
--> diag7.rs:4:13
|
4 | let _ = S.new;
| ^
|
- = note: can't use a type alias as a constructor
+ help: use the path separator to refer to an item
+ |
+4 | let _ = S::new;
+ | ~~
```
</details>
Second commit adds some cases for `enum`s, where if there is a field/method expression where the field/method has the name of a unit/tuple variant, we assume the user intended to create that variant[^1] and suggest replacing the `.` from the field/method suggestion with a `::` path separator. If no such variant is found (or if the error is not a field/method expression), we give the existing suggestion that suggests adding `::TupleVariant(/* fields */)` after the enum.
<details> <summary> Enum diagnostic example </summary>
```rust
enum Foo {
A(u32),
B,
C { x: u32 },
}
fn main() {
let _ = Foo.A(42); // changed
let _ = Foo.B; // changed
let _ = Foo.D(42); // no change
let _ = Foo.D; // no change
let _ = Foo(42); // no change
}
```
```diff
error[E0423]: expected value, found enum `Foo`
--> diag8.rs:8:13
|
8 | let _ = Foo.A(42); // changed
| ^^^
|
note: the enum is defined here
--> diag8.rs:1:1
|
1 | / enum Foo {
2 | | A(u32),
3 | | B,
4 | | C { x: u32 },
5 | | }
| |_^
-help: you might have meant to use the following enum variant
- |
-8 | let _ = Foo::B.A(42); // changed
- | ~~~~~~
-help: alternatively, the following enum variant is available
+help: use the path separator to refer to a variant
|
-8 | let _ = (Foo::A(/* fields */)).A(42); // changed
- | ~~~~~~~~~~~~~~~~~~~~~~
+8 | let _ = Foo::A(42); // changed
+ | ~~
error[E0423]: expected value, found enum `Foo`
--> diag8.rs:9:13
|
9 | let _ = Foo.B; // changed
| ^^^
|
note: the enum is defined here
--> diag8.rs:1:1
|
1 | / enum Foo {
2 | | A(u32),
3 | | B,
4 | | C { x: u32 },
5 | | }
| |_^
-help: you might have meant to use the following enum variant
- |
-9 | let _ = Foo::B.B; // changed
- | ~~~~~~
-help: alternatively, the following enum variant is available
+help: use the path separator to refer to a variant
|
-9 | let _ = (Foo::A(/* fields */)).B; // changed
- | ~~~~~~~~~~~~~~~~~~~~~~
+9 | let _ = Foo::B; // changed
+ | ~~
error[E0423]: expected value, found enum `Foo`
--> diag8.rs:10:13
|
10 | let _ = Foo.D(42); // no change
| ^^^
|
note: the enum is defined here
--> diag8.rs:1:1
|
1 | / enum Foo {
2 | | A(u32),
3 | | B,
4 | | C { x: u32 },
5 | | }
| |_^
help: you might have meant to use the following enum variant
|
10 | let _ = Foo::B.D(42); // no change
| ~~~~~~
help: alternatively, the following enum variant is available
|
10 | let _ = (Foo::A(/* fields */)).D(42); // no change
| ~~~~~~~~~~~~~~~~~~~~~~
error[E0423]: expected value, found enum `Foo`
--> diag8.rs:11:13
|
11 | let _ = Foo.D; // no change
| ^^^
|
note: the enum is defined here
--> diag8.rs:1:1
|
1 | / enum Foo {
2 | | A(u32),
3 | | B,
4 | | C { x: u32 },
5 | | }
| |_^
help: you might have meant to use the following enum variant
|
11 | let _ = Foo::B.D; // no change
| ~~~~~~
help: alternatively, the following enum variant is available
|
11 | let _ = (Foo::A(/* fields */)).D; // no change
| ~~~~~~~~~~~~~~~~~~~~~~
error[E0423]: expected function, tuple struct or tuple variant, found enum `Foo`
--> diag8.rs:12:13
|
12 | let _ = Foo(42); // no change
| ^^^ help: try to construct one of the enum's variants: `Foo::A`
|
= help: you might have meant to construct the enum's non-tuple variant
note: the enum is defined here
--> diag8.rs:1:1
|
1 | / enum Foo {
2 | | A(u32),
3 | | B,
4 | | C { x: u32 },
5 | | }
| |_^
error: aborting due to 5 previous errors
```
</details>
[^1]: or if it's a field expression and a tuple variant, that they meant to refer the variant constructor.
Match Ergonomics 2024: update old-edition behavior of feature gates
This updates the behavior of the feature gates `ref_pat_eat_one_layer_2024_structural` and `ref_pat_eat_one_layer_2024` in Editions 2021 and earlier to correspond to the left and right typing rules compared [here](https://nadrieril.github.io/typing-rust-patterns/?opts1=AQEBAQIBAQEBAAAAAAAAAAAAAAAAAAA%3D&style=UserVisible&compare=true&opts2=AQEBAQIBAQABAAAAAQEBAAEBAAABAAA%3D&mode=rules), respectively. Compared to the `stable_rust` rules:
- they both allow reference patterns to match a lone inherited ref,
- they both allow `&` patterns to eat `&mut` reference types (and lone `&mut` inherited refs) as if they're shared,
- they both allow `&mut` patterns to eat `&` reference types when there's a `&mut` inherited reference to also eat,
- and the left ruleset has RFC 3627's Rule 3: after encountering a shared reference type in the scrutinee, the default binding mode will be treated as by-shared-ref when it would otherwise be by-mutable-ref.
I think there's already tests for all of those typing rules, so I've added revisions to use the existing tests with the new rulesets. Additionally, I've added a few tests to make sure we handle mixed-edition patterns appropriately, and I've added references to the unstable book.
Relevant tracking issue: #123076
r? ``@ghost``
- 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
```
warning: cannot find macro `in_root` in the crate root
--> $DIR/key-value-expansion-scope.rs:1:10
|
LL | #![doc = in_root!()]
| ^^^^^^^ not found in the crate root
|
= warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
= note: for more information, see issue #124535 <https://github.com/rust-lang/rust/issues/124535>
= help: import `macro_rules` with `use` to make it callable above its definition
= note: `#[warn(out_of_scope_macro_calls)]` on by default
```
This commit removes the `avr-unknown-gnu-atmega328` target and replaces
it with a more generic `avr-none` variant that must be specialized with
the `-C target-cpu` flag (e.g. `-C target-cpu=atmega328p`).
coverage: Get hole spans from nested items without fully visiting them
This is a small simplification to the code that collects the spans of nested items within a function, so that those spans can be treated as “holes” to be avoided by the current function's coverage mappings.
The old code was using `nested_filter::All` to ensure that the visitor would see nested items. But we don't need the actual items themselves; we just need their spans, which we can obtain via a custom implementation of `visit_nested_item`.
This avoids the more expansive queries required by `nested_filter::All`.
Don't mention `FromResidual` on bad `?`
Unless `try_trait_v2` is enabled, don't mention that `FromResidual` isn't implemented for a specific type when the implicit `From` conversion of a `?` fails. For the end user on stable, `?` might as well be a compiler intrinsic, so we remove that note to avoid further confusion and allowing other parts of the error to be more prominent.
```
error[E0277]: `?` couldn't convert the error to `u8`
--> $DIR/bad-interconversion.rs:4:20
|
LL | fn result_to_result() -> Result<u64, u8> {
| --------------- expected `u8` because of this
LL | Ok(Err(123_i32)?)
| ------------^ the trait `From<i32>` is not implemented for `u8`
| |
| this can't be annotated with `?` because it has type `Result<_, i32>`
|
= note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait
= help: the following other types implement trait `From<T>`:
`u8` implements `From<Char>`
`u8` implements `From<bool>`
```
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.
rustfmt doesn't touch it because it's a macro body, but it's large
enough that the misformatting is annoying. This commit improves it. The
most common problems fixed:
- Unnecessary multi-line patterns reduced to one line.
- Multi-line function headers adjusted so the parameter indentation
doesn't depend on the length of the function name. (This is Rust code,
not C.)
- `|` used at the start of lines, not the end.
- More consistent formatting of empty function bodies.
- Overly long lines are broken.
The `MirVisitable` trait is just a complicated way to visit either a
statement or a terminator. (And its impl for `Terminator` is unused.) It
has a single use.
This commit removes it, replacing it with an if/else, which is shorter
and simpler.
`visit_local` is the only method that doesn't call a corresponding
`super_local` method. This is valid, because `super_local` would be
empty. But it's inconsistent with every other case; we have multiple
other empty `super` methods: `super_span`, `super_ty`, etc.
This commit adds an empty `super_local` and makes `visit_local` call it.
Emit dropck normalization errors in borrowck
Borrowck generally assumes that any queries it runs for type checking will succeed, thinking that HIR typeck will have errored first if there was a problem. However as of #98641, dropck isn't run on HIR, so there's no direct guarantee that it doesn't error. While a type being well-formed might be expected to ensure that its fields are well-formed, this is not the case for types containing a type projection:
```rust
pub trait AuthUser {
type Id;
}
pub trait AuthnBackend {
type User: AuthUser;
}
pub struct AuthSession<Backend: AuthnBackend> {
data: Option<<<Backend as AuthnBackend>::User as AuthUser>::Id>,
}
pub trait Authz: Sized {
type AuthnBackend: AuthnBackend<User = Self>;
}
pub fn run_query<User: Authz>(auth: AuthSession<User::AuthnBackend>) {}
// ^ No User: AuthUser bound is required or inferred.
```
While improvements to trait solving might fix this in the future, for now we go for a pragmatic solution of emitting an error from borrowck (by rerunning dropck outside of a query) and making drop elaboration check if an error has been emitted previously before panicking for a failed normalization.
Closes#103899Closes#135039
r? `@compiler-errors` (feel free to re-assign)
Rollup of 9 pull requests
Successful merges:
- #136936 (Use 'yes' instead of 'while-echo' in tests/ui/process/process-sigpipe.rs except 'nto')
- #137026 (Stabilize (and const-stabilize) `integer_sign_cast`)
- #137059 (fix: Alloc new errorcode E0803 for E0495)
- #137177 (Update `minifier-rs` version to `0.3.5`)
- #137210 (compiler: Stop reexporting stuff in cg_llvm::abi)
- #137213 (Remove `rustc_middle::mir::tcx` module.)
- #137216 (eval_outlives: bail out early if both regions are in the same SCC)
- #137228 (Fix typo in hidden internal docs of `TrustedRandomAccess`)
- #137242 (Add reference annotations for the `do_not_recommend` attribute)
r? `@ghost`
`@rustbot` modify labels: rollup
It turns out that this visitor doesn't actually need `nested_filter::All` to
handle nested items; it just needs to override `visit_nested_item` and look up
the item's span.
My reasoning: the ruleset implemented by the same feature gate in
Edition 2024 always tries to eat the inherited reference first. For
consistency, it makes sense to me to say across all editions that users
should consider the inherited reference's mutability when wondering if a
`&mut` pattern will type.
x86: use SSE2 to pass float and SIMD types
This builds on the new X86Sse2 ABI landed in https://github.com/rust-lang/rust/pull/137037 to actually make it a separate ABI from the default x86 ABI, and use SSE2 registers. Specifically, we use it in two ways: to return `f64` values in a register rather than by-ptr, and to pass vectors of size up to 128bit in a register (or, well, whatever LLVM does when passing `<4 x float>` by-val, I don't actually know if this ends up in a register).
Cc `@workingjubilee`
Fixes#133611
try-job: aarch64-apple
try-job: aarch64-gnu
try-job: aarch64-gnu-debug
try-job: test-various
try-job: x86_64-gnu-nopt
try-job: dist-i586-gnu-i586-i686-musl
try-job: x86_64-msvc-1
eval_outlives: bail out early if both regions are in the same SCC
A drive-by optimisation of region outlives evaluation: if we are evaluating whether an outlives holds for two regions, bail out early if they are both in the same SCC.
This probably won't make a huge difference, but the cost is one comparison of SCC indices (integers).
May want a perf run, depending on how confident whomever reviewing this is!
Remove `rustc_middle::mir::tcx` module.
This is a really weird module. For example, what does `tcx` in `rustc_middle::mir::tcx::PlaceTy` mean? The answer is "not much".
The top-level module comment says:
> Methods for the various MIR types. These are intended for use after
> building is complete.
Awfully broad for a module that has a handful of impl blocks for some MIR types, none of which really relates to `TyCtxt`. `git blame` indicates the comment is ancient, from 2015, and made sense then.
This module is now vestigial. This commit removes it and moves all the code within into `rustc_middle::mir::statement`. Some specifics:
- `Place`, `PlaceRef`, `Rvalue`, `Operand`, `BorrowKind`: they all have `impl` blocks in both the `tcx` and `statement` modules. The commit merges the former into the latter.
- `BinOp`, `UnOp`: they only have `impl` blocks in `tcx`. The commit moves these into `statement`.
- `PlaceTy`, `RvalueInitializationState`: they are defined in `tcx`. This commit moves them into `statement` *and* makes them available in `mir::*`, like many other MIR types.
r? `@tmandry`
compiler: Stop reexporting stuff in cg_llvm::abi
The reexports confuse tooling like rustdoc into thinking cg_llvm is the source of key types that originate in rustc_target.
This is a really weird module. For example, what does `tcx` in
`rustc_middle::mir::tcx::PlaceTy` mean? The answer is "not much".
The top-level module comment says:
> Methods for the various MIR types. These are intended for use after
> building is complete.
Awfully broad for a module that has a handful of impl blocks for some
MIR types, none of which really relates to `TyCtxt`. `git blame`
indicates the comment is ancient, from 2015, and made sense then.
This module is now vestigial. This commit removes it and moves all the
code within into `rustc_middle::mir::statement`. Some specifics:
- `Place`, `PlaceRef`, `Rvalue`, `Operand`, `BorrowKind`: they all have `impl`
blocks in both the `tcx` and `statement` modules. The commit merges
the former into the latter.
- `BinOp`, `UnOp`: they only have `impl` blocks in `tcx`. The commit
moves these into `statement`.
- `PlaceTy`, `RvalueInitializationState`: they are defined in `tcx`.
This commit moves them into `statement` *and* makes them available in
`mir::*`, like many other MIR types.
Suggest replacing `.` with `::` when encountering "expected value, found enum":
- in a method-call expression and the method has the same name as a tuple variant
- in a field-access expression and the field has the same name as a unit or tuple variant
When `Foo.field` or `Foo.method()` exprs are encountered, suggest `Foo::field` or `Foo::method()` when Foo is a type alias, not just
a struct, trait, or module.
Also rename test for this suggestion from issue-22692.rs to something more meaningful.
Pattern Migration 2024: fix incorrect messages/suggestions when errors arise in macro expansions
See the diff between the two commits for how this affected the error message and suggestion. In order to decide how to format those, the pattern migration diagnostic keeps track of which parts of the user's pattern cause problems in Edition 2024. However, it neglected to do some of this bookkeeping when pointing to macro expansion sites. This fixes that.
Do not ICE on default_field_value const with lifetimes
`#![feature(default_field_values)]` uses a `const` body that should be treated as inline `const`s, but is actually being detected otherwise. This is similar to the situation in #78174, so we take the same solution: we check if the const actually comes from a field, and if it does, we use that logic to get the appropriate lifetimes and not ICE during borrowck.
Fix#135649.
Unless `try_trait_v2` is enabled, don't mention that `FromResidual` isn't implemented for a specific type when the implicit `From` conversion of a `?` fails. For the end user on stable, `?` might as well be a compiler intrinsic, so we remove that note to avoid further confusion and allowing other parts of the error to be more prominent.
```
error[E0277]: `?` couldn't convert the error to `u8`
--> $DIR/bad-interconversion.rs:4:20
|
LL | fn result_to_result() -> Result<u64, u8> {
| --------------- expected `u8` because of this
LL | Ok(Err(123_i32)?)
| ------------^ the trait `From<i32>` is not implemented for `u8`
| |
| this can't be annotated with `?` because it has type `Result<_, i32>`
|
= note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait
= help: the following other types implement trait `From<T>`:
`u8` implements `From<Char>`
`u8` implements `From<bool>`
```
Enforce T: Hash for Interned<...>
This adds panicking Hash impls for several resolver types that don't actually satisfy this condition. It's not obvious to me that rustc_resolve actually upholds the Interned guarantees but fixing that seems pretty hard (the structures have at minimum some interior mutability, so it's not really recursively hashable in place...). FIXME comments as such on those impls.
cc https://github.com/rust-lang/rust/pull/137196#issuecomment-2664350287
r? ``@saethlin``
cg_clif: use exclusively ABI alignment
This will minimize possible conflict with future updates to AbiAndPrefAlign that may remove some fields. It is also almost a bug to consider them.
r? ``@bjorn3``
Install more signal stack trace handlers
This PR install the signal stack handler to more signals (`SIGILL`, ~~`SIGTRAP`~~, ~~`SIGABRT`~~, ~~`SIGFPE`~~, `SIGBUS`, ~~`SIGQUIT`~~).
Noticed in https://github.com/rust-lang/rust/issues/137138 that we didn't print anything for `SIGILL`, so I though we could just handle more signals.
r? `````@workingjubilee````` since you last touched it
- change function parameter order to `cx, ty, ...` to match the other
functions in this file
- use `ct` identifier for `ty::Const` to match the majority of the
compiler codebase
- remove useless return
- bring match arms in a more natural order
Remove the `repr` parameter from the wrappers around `calc.univariant`,
because it's always defaulted. Only ADTs can have a repr and those call
`calc.layout_of_struct_or_enum` and not `calc.univariant`.
- we normalize before calling `layout_of_uncached`, so we don't need to
normalize again later
- we check for type/const errors at the top of `layout_of_uncached`, so
we don't need to check again later
`ty::Placeholder` is used by the trait solver and computing its layout
was necessary, because the `PointerLike` trait used to be automatically
implemented for all types with pointer-like layout.
Nowadays, `PointerLike` requires user-written impls and the trait solver
no longer computes any layouts, so this can be removed.
Unevaluated constants that aren't generic should have caused a const eval
error earlier during normalization.
improve cold_path()
#120370 added a new instrinsic `cold_path()` and used it to fix `likely` and `unlikely`
However, in order to limit scope, the information about cold code paths is only used in 2-target switch instructions. This is sufficient for `likely` and `unlikely`, but limits usefulness of `cold_path` for idiomatic rust. For example, code like this:
```
if let Some(x) = y { ... }
```
may generate 3-target switch:
```
switch y.discriminator:
0 => true branch
1 = > false branch
_ => unreachable
```
and therefore marking a branch as cold will have no effect.
This PR improves `cold_path()` to work with arbitrary switch instructions.
Note that for 2-target switches, we can use `llvm.expect`, but for multiple targets we need to manually emit branch weights. I checked Clang and it also emits weights in this situation. The Clang's weight calculation is more complex that this PR, which I believe is mainly because `switch` in `C/C++` can have multiple cases going to the same target.
Move methods from `Map` to `TyCtxt`, part 2.
Continuing the work started in #136466.
Every method gains a `hir_` prefix, though for the ones that already have a `par_` or `try_par_` prefix I added the `hir_` after that.
r? Zalathar
This adds panicking Hash impls for several resolver types that don't
actually satisfy this condition. It's not obvious to me that
rustc_resolve actually upholds the Interned guarantees but fixing that
seems pretty hard (the structures have at minimum some interior
mutability, so it's not really recursively hashable in place...).
It's currently lacking comments. This commit adds some, which is useful
because there are some methods with non-obvious behaviour.
The commit also renames two things:
- `patch_map` becomes `term_patch_map`, because it's only about
terminators.
- `is_patched` becomes `is_term_patched`, for the same reason.
(I would guess that originally `MirPatch` only handled terminators, and
then over time it expanded to allow other modifications, but these names
weren't updated.)
Instead of `expand_statements`. This makes the code shorter and
consistent with other MIR transform passes.
The tests require updating because there is a slight change in
MIR output:
- the old code replaced the original statement with twelve new
statements.
- the new code inserts converts the original statement to a `nop` and
then insert twelve new statements in front of it.
I.e. we now end up with an extra `nop`, which doesn't matter at all.
Continuing the work started in #136466.
Every method gains a `hir_` prefix, though for the ones that already
have a `par_` or `try_par_` prefix I added the `hir_` after that.
Drop elaboration looks at fields of a type, which may error when we try
to normalize them. Borrowck will have detected this if HIR typeck
didn't, but we don't delete the MIR body for errors in borrowck so
still have to handle this happening in drop elaboration by checking
whether an error has been emitted.
HIR type checking no longer runs dropck, so we may get new errors when
we run it in borrowck. If this happens then rerun the query in a local
infcx and report errors for it.
Rollup of 7 pull requests
Successful merges:
- #137095 (Replace some u64 hashes with Hash64)
- #137100 (HIR analysis: Remove unnecessary abstraction over list of clauses)
- #137105 (Restrict DerefPure for Cow<T> impl to T = impl Clone, [impl Clone], str.)
- #137120 (Enable `relative-path-include-bytes-132203` rustdoc-ui test on Windows)
- #137125 (Re-add missing empty lines in the releases notes)
- #137145 (use add-core-stubs / minicore for a few more tests)
- #137149 (Remove SSE ABI from i586-pc-windows-msvc)
r? `@ghost`
`@rustbot` modify labels: rollup
Remove SSE ABI from i586-pc-windows-msvc
As an i586 target, it should not have SSE. This caused the following warning to be emitted:
```
warning: target feature `sse2` must be enabled to ensure that the ABI of the current target can be implemented correctly
|
= note: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
= note: for more information, see issue #116344 <https://github.com/rust-lang/rust/issues/116344>
warning: 1 warning emitted
```
see #116344.
r? RalfJung
HIR analysis: Remove unnecessary abstraction over list of clauses
`rustc_hir_analysis::bounds::Bounds` with its methods is nowadays a paper-thin wrapper around `Vec<(Clause, Span)>`s and `Vec::push` essentially.
Its existence slightly annoyed me (and I keep opening its corresp. file instead of the identically named `bounds.rs` in `hir_ty_lowering/` that I actually want most of the time :P).
Opening to check if you agree with inlining it.
r? compiler-errors or reassign
Replace some u64 hashes with Hash64
I introduced the Hash64 and Hash128 types in https://github.com/rust-lang/rust/pull/110083, essentially as a mechanism to prevent hashes from landing in our leb128 encoding paths. If you just have a u64 or u128 field in a struct then derive Encodable/Decodable, that number gets leb128 encoding. So if you need to store a hash or some other value which behaves very close to a hash, don't store it as a u64.
This reverts part of https://github.com/rust-lang/rust/pull/117603, which turned an encoded Hash64 into a u64.
Based on https://github.com/rust-lang/rust/pull/110083, I don't expect this to be perf-sensitive on its own, though I expect that it may help stabilize some of the small rmeta size fluctuations we currently see in perf reports.
Fix const items not being allowed to be called `r#move` or `r#static`
Because of an ambiguity with const closures, the parser needs to ensure that for a const item, the `const` keyword isn't followed by a `move` or `static` keyword, as that would indicate a const closure:
```rust
fn main() {
const move // ...
}
```
This check did not take raw identifiers into account, therefore being unable to distinguish between `const move` and `const r#move`. The latter is obviously not a const closure, so it should be allowed as a const item.
This fixes the check in the parser to only treat `const ...` as a const closure if it's followed by the *proper keyword*, and not a raw identifier.
Additionally, this adds a large test that tests for all raw identifiers in all kinds of positions, including `const`, to prevent issues like this one from occurring again.
fixes#137128
Pattern Migration 2024: clean up and comment
This follows up on #136577 by moving the pattern migration logic to its own module, removing a bit of unnecessary complexity, and adding comments. Since there's quite a bit of pattern migration logic now (and potentially more in #136496), I think it makes sense to keep it separate from THIR construction, at least as much as is convenient.
r? ``@Nadrieril``
Overhaul `rustc_middle::limits`
In particular, to make `pattern_complexity` work more like other limits, which then enables some other simplifications.
r? ``@Nadrieril``
Start removing `rustc_middle::hir::map::Map`
`rustc_middle::hir::map::Map` is now just a low-value wrapper around `TyCtxt`. This PR starts removing it.
r? `@cjgillot`
First of all, note that `Map` has three different relevant meanings.
- The `intravisit::Map` trait.
- The `map::Map` struct.
- The `NestedFilter::Map` associated type.
The `intravisit::Map` trait is impl'd twice.
- For `!`, where the methods are all unreachable.
- For `map::Map`, which gets HIR stuff from the `TyCtxt`.
As part of getting rid of `map::Map`, this commit changes `impl
intravisit::Map for map::Map` to `impl intravisit::Map for TyCtxt`. It's
fairly straightforward except various things are renamed, because the
existing names would no longer have made sense.
- `trait intravisit::Map` becomes `trait intravisit::HirTyCtxt`, so named
because it gets some HIR stuff from a `TyCtxt`.
- `NestedFilter::Map` assoc type becomes `NestedFilter::MaybeTyCtxt`,
because it's always `!` or `TyCtxt`.
- `Visitor::nested_visit_map` becomes `Visitor::maybe_tcx`.
I deliberately made the new trait and associated type names different to
avoid the old `type Map: Map` situation, which I found confusing. We now
have `type MaybeTyCtxt: HirTyCtxt`.
The end goal is to eliminate `Map` altogether.
I added a `hir_` prefix to all of them, that seemed simplest. The
exceptions are `module_items` which became `hir_module_free_items` because
there was already a `hir_module_items`, and `items` which became
`hir_free_items` for consistency with `hir_module_free_items`.
It's always good to make `rustc_middle` smaller. `rustc_interface` is
the best destination, because it's the only crate that calls
`get_recursive_limit`.
It's similar to the other limits, e.g. obtained via `get_limit`. So it
makes sense to handle it consistently with the other limits. We now use
`Limit`/`usize` in most places instead of `Option<usize>`, so we use
`Limit::new(usize::MAX)`/`usize::MAX` to emulate how `None` used to work.
The commit also adds `Limit::unlimited`.
The .ptx version produced by llc can be specified by passing it with --mattr. Currently it is not possible to specify the .ptx version with -Ctarget-feature because these are not passed through to llvm-bitcode-linker and handled by it. This commit adds both.
--target-feature and -mattr are passed with equals to mitigate issues when the value starts with a - (minus).
Bitcode linkers like llvm-bitcode-linker or bpf linker hand over the target features to llvm during link stage. During link stage the `TyCtxt` is already gone so it is not possible to create a query for the global backend features any longer. The features preserved in `Session.target_features` only incorporate target features known to rustc. This would contradict with the behaviour during codegen stage which also passes target features to llvm which are unknown to rustc.
This commit adds target features as a field to the `CrateInfo` struct and queries the target features in its new function. This way the target features are preserved beyond tcx and available at link stage.
To make sure the `global_backend_features` query is always registered even if the CodegenBackend does not register it, this registration is added to the `provide`function of the `rustc_codegen_ssa` crate.
As an i586 target, it should not have SSE. This caused the following
warning to be emitted:
```
warning: target feature `sse2` must be enabled to ensure that the ABI of the current target can be implemented correctly
|
= note: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
= note: for more information, see issue #116344 <https://github.com/rust-lang/rust/issues/116344>
warning: 1 warning emitted
```
Because of an ambiguity with const closures, the parser needs to ensure
that for a const item, the `const` keyword isn't followed by a `move` or
`static` keyword, as that would indicate a const closure:
```rust
fn main() {
const move // ...
}
```
This check did not take raw identifiers into account, therefore being
unable to distinguish between `const move` and `const r#move`. The
latter is obviously not a const closure, so it should be allowed as a
const item.
This fixes the check in the parser to only treat `const ...` as a const
closure if it's followed by the *proper keyword*, and not a raw
identifier.
Additionally, this adds a large test that tests for all raw identifiers in
all kinds of positions, including `const`, to prevent issues like this
one from occurring again.
Rework `name_regions` to not rely on reverse scc graph for non-member-constrain usages
Fixes https://github.com/rust-lang/rust/issues/137015
Splits the `name_regions` into two versions: One meant for member region constraint error reporting (which I've renamed to `name_regions_for_member_constraint`), and one meant *just* to replace region vids with an external region.
Use the latter in the usage sites I added in #136559, since the regions returned by `name_regions_for_member_constraint` are also not *totally* accurate (which is fine for how they're used for member region constraint error reporting -- they're intentionally returning overapproximated universal regions so that we have something to name in `+ use<'a>` suggestions, because opaques can only capture universal regions and since member region constraints don't insert any edges into the region graph, the error region is probably gonna be shorter than a universal region) and because that function requires the reverse scc graph to have been computed which isn't done for our usages in #136559.
Load all builtin targets at once instead of one by one in check-cfg
This PR adds a method on `rustc_target::Target` to load all the builtin targets at once, and then uses that method when constructing the `target_*` values in check-cfg instead of load loading each target one by one by their name, which requires a lookup and was more of a hack anyway.
This may give us some performance improvements as we won't need to do the lookup for the _currently_ 287 targets we have.
rustdoc: improve refdef handling in the unresolved link lint
This commit takes advantage of a feature in pulldown-cmark that makes the list of link definitions available to the consuming application. It produces unresolved link warnings for refdefs that aren't used, and can now produce exact spans for the dest even when it has escapes.
Closes#133150 since this lint would have caught the mistake in that issue, and, along with https://github.com/rust-lang/rust-clippy/pull/13707, most mistakes in this class should produce a warning from one of them.
Rollup of 5 pull requests
Successful merges:
- #135797 (Import initial generated 1.85 relnotes)
- #135909 (Export kernel descriptor for amdgpu kernels)
- #136545 (nvptx64: update default alignment to match LLVM 21)
- #137092 (abi_unsupported_vector_types: say which type is the problem)
- #137097 (Ignore Self in bounds check for associated types with Self:Sized)
r? `@ghost`
`@rustbot` modify labels: rollup
nvptx64: update default alignment to match LLVM 21
This changed in llvm/llvm-project@91cb8f5d32. The commit itself is mostly about some intrinsic instructions, but as an aside it also mentions something about addrspace for tensor memory, which I believe is what this string is telling us.
`@rustbot` label: +llvm-main
Export kernel descriptor for amdgpu kernels
The host runtime (HIP or HSA) expects a kernel descriptor object for each kernel in the ELF file. The amdgpu LLVM backend generates the object. It is created as a symbol with the name of the kernel plus a `.kd` suffix.
Add it to the exported symbols in the linker script, so that it can be found.
For reference, the symbol is created here in LLVM: d5457e4c16/llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUTargetStreamer.cpp (L966)
I wrote [a test](6a9115b121) for this as well, I’ll add that once the target is merged and working.
With this, all PRs to get working code for amdgpu are open (this + the target + the two patches adding addrspacecasts for alloca and global variables).
Tracking issue: #135024
r? `@workingjubilee`
This commit takes advantage of a feature in pulldown-cmark that
makes the list of link definitions available to the consuming
application. It produces unresolved link warnings for refdefs
that aren't used, and can now produce exact spans for the dest
even when it has escapes.
Try to recover from path sep error in type parsing
Fixes#129273
Error using `:` in the argument list may mess up the parser.
case `tests/ui/suggestions/struct-field-type-including-single-colon` also changed, seems it's the same meaning, should be OK.
r? `@estebank`
Do not allow attributes on struct field rest patterns
Fixes#81282.
This removes support for attributes on struct field rest patterns (the `..` bit) from the parser. Previously any attributes were being parsed but dropped from the AST, so didn't work and were deleted by rustfmt.
This needs an equivalent change to the reference but I wanted to see how this PR is received first.
The error message it produces isn't great, however it does match the error you get if you try to add attributes to .. in struct expressions atm, although I can understand wanting to do better given this was previously accepted. I think I could move attribute parsing back up to where it was and then emit a specific new error for this case, however I might need some guidance as this is the first time I've messed around inside the compiler.
While this is technically breaking I don't think it's much of an issue: attributes in this position don't currently do anything and rustfmt outright deletes them, meaning it's incredibly unlikely to affect anyone. I have already made the equivalent change to *add* support for attributes (mostly) but the conversation in the linked issue suggested it would be more reasonable to just remove them (and pointed out it's much easier to add support later if we realise we need them).
Fix crate name validation
Reject macro calls inside attribute `#![crate_name]` like in `#![crate_name = concat!("na", "me")]`.
Prior to #117584, the result of the expansion (here: `"name"`) would actually be properly picked up by the compiler and used as the crate name. However since #117584 / on master, we extract the "value" (i.e., the *literal* string literal) of the `#![crate_name]` much earlier in the pipeline way before macro expansion and **skip**/**ignore** any `#![crate_name]`s "assigned to" a macro call. See also #122001.
T-lang has ruled to reject `#![crate_name = MACRO!(...)]` outright very similar to other built-in attributes whose value we need early like `#![crate_type]`. See accepted FCP: https://github.com/rust-lang/rust/issues/122001#issuecomment-2023203182.
Note that the check as implemented in this PR is even more "aggressive" compared to the one of `#![crate_type]` by running as early as possible in order to reject `#![crate_name = MACRO!(...)]` even in "non-normal" executions of `rustc`, namely on *print requests* (e.g., `--print=crate-name` and `--print=file-names`). If I were to move the validation step a bit further back close to the `#![crate_type]` one, `--print=crate-name` (etc.) would *not* exit fatally with an error in this kind of situation but happily report an incorrect crate name (i.e., the "crate name" as if `#![crate_name]` didn't exist / deduced from other sources like `--crate-name` or the file name) which would match the behavior on master. Again, see also #122001.
I'm mentioning this explicitly because I'm not sure if it was that clear in the FCP'ed issue. I argue that my current approach is the most reasonable one. I know (from reading the code and from past experiments) that various print requests are still quite broken (mostly lack of validation).
To the best of my knowledge, there's no print request whose output references/contains a crate *type*, so there's no "inherent need" to move `#![crate_type]`'s validation to happen earlier.
---
Fixes#122001.
https://github.com/rust-lang/rust/labels/relnotes: Compatibility. Breaking change.
mir_build: Clarify some code for lowering `hir::PatExpr` to THIR
A few loosely-related improvements to the code that lowers certain parts of HIR patterns to THIR.
I was originally deferring this until after #136529, but that PR probably won't happen, whereas these changes should hopefully be uncontroversial.
r? Nadrieril or reroll
add x86-sse2 (32bit) ABI that requires SSE2 target feature
This is the first commit of https://github.com/rust-lang/rust/pull/135408:
The primary goal of this is to make SSE2 required for our i686 targets (at least for the ones that use Pentium 4 as their baseline), to ensure they cannot be affected by https://github.com/rust-lang/rust/issues/114479. This has been MCPd in https://github.com/rust-lang/compiler-team/issues/808, and is tracked in https://github.com/rust-lang/rust/issues/133611.
We do this by defining a new ABI that these targets select, and making SSE2 required by the ABI (that's the first commit). That's kind of a hack, but it is the easiest way to make a target feature required via the target spec. In a follow-up change (https://github.com/rust-lang/rust/pull/135408), we can actually make use of SSE2 for the ABI, but that is running into some infrastructure issues.
r? `@workingjubilee`
try-job: aarch64-apple
try-job: aarch64-gnu
try-job: aarch64-gnu-debug
try-job: test-various
try-job: x86_64-gnu-nopt
try-job: dist-i586-gnu-i586-i686-musl
Normalize closure instance before eagerly monomorphizing it
We were monomorphizing two versions of the closure (or in the original issue, coroutine) -- one with normalized captures and one with unnormalized captures. This led to a symbol collision.
Fixes#137009
r? `@saethlin` or reassign
borrowck diagnostics cleanup: remove an unused and a barely-used field
This removes the fields `fr_is_local` and `outlived_fr_is_local` from the struct `ErrorConstraintInfo`. `fr_is_local` was fully unused, but wasn't caught by dead-code analysis. For symmetry, and since `outlived_fr_is_local` was used only once and is easy to recompute, I've removed it too. That makes its one use a bit longer, but constructing/destructuring an `ErrorConsraintInfo` now fits on one line.
Rollup of 9 pull requests
Successful merges:
- #135778 (account for `c_enum_min_bits` in `multiple-reprs` UI test)
- #136052 (Correct comment for FreeBSD and DragonFly BSD in unix/thread)
- #136886 (Remove the common prelude module)
- #136956 (add vendor directory to .gitignore)
- #136958 (Fix presentation of purely "additive" replacement suggestion parts)
- #136967 (Use `slice::fill` in `io::Repeat` implementation)
- #136976 (alloc boxed: docs: use MaybeUninit::write instead of as_mut_ptr)
- #137007 (Emit MIR for each bit with on `dont_reset_cast_kind_without_updating_operand`)
- #137008 (Move code into `rustc_mir_transform`)
r? `@ghost`
`@rustbot` modify labels: rollup
Move code into `rustc_mir_transform`
I found two modules in other crates that are better placed in `rustc_mir_transform`, because that's the only crate that uses them.
r? ``@matthewjasper``
Fix presentation of purely "additive" replacement suggestion parts
#127541 changes replacement suggestions to use the "diff" view always, which I think is really verbose in cases where a replacement snippet is a "superset" of the snippet that is being replaced.
Consider:
```
LL - Self::Baz: Clone,
LL + Self::Baz: Clone, T: std::clone::Clone
```
In this code, we suggest replacing `", "` with `", T: std::clone::Clone"`. This is a consequence of how the snippet is constructed. I believe that since the string that is being replaced is a subset of the replacement string, it's not providing much value to present this as a diff. Users should be able to clearly understand what's being suggested here using the `~` underline view we've been suggesting for some time now.
Given that this affects ~100 tests out of the ~1000 UI tests affected, I expect this to be a pretty meaningful improvement of the fallout of #127541.
---
In the last commit, this PR also "trims" replacement parts so that they are turned into their purely additive subset, if possible. See the diff for what this means.
---
r? estebank
Set both `nuw` and `nsw` in slice size calculation
There's an old note in the code to do this, and now that [LLVM-C has an API for it](f0b8ff1251/llvm/include/llvm-c/Core.h (L4403-L4408)), we might as well. And it's been there since what looks like LLVM 17 de9b6aa341 so doesn't even need to be conditional.
(There's other places, like `RawVecInner` or `Layout`, that might want to do things like this too, but I'll leave those for a future PR.)
The formatting of the command line arguments has been moved to the
frontend in:
e190d074a0
However, the Rust logic introduced in
ad0ecebf43
did not replicate the previous argument quoting behavior.
`transmute` should also assume non-null pointers
Previously it only did integer-ABI things, but this way it does data pointers too. That gives more information in general to the backend, and allows slightly simplifying one of the helpers in slice iterators.
Simplify `rustc_span` `analyze_source_file`
Simplifies the logic to what the code *actually* does, which is to just record newlines and multibyte characters. Checking for other ASCII control characters is unnecessary because the generic fallback doesn't do anything for those cases.
Also uses a simpler (and more efficient) means of iterating the set bits of the mask.
Because it's only used in `rustc_mir_transform`. (Presumably it is
currently in `rustc_middle` because lots of other MIR-related stuff is,
but that's not a hard requirement.) And because `rustc_middle` is huge
and it's always good to make it smaller.
`rustc_mir_dataflow/src/elaborate_drops.rs` contains some infrastructure
used by a few MIR passes: the `elaborate_drop` function, the
`DropElaborator` trait, etc.
`rustc_mir_transform/src/elaborate_drops.rs` (same file name, different
crate) contains the `ElaborateDrops` pass. It relies on a lot of the
infrastructure from `rustc_mir_dataflow/src/elaborate_drops.rs`.
It turns out that the drop infrastructure is only used in
`rustc_mir_transform`, so this commit moves it there. (The only
exception is the small `DropFlagState` type, which is moved to the
existing `rustc_mir_dataflow/src/drop_flag_effects.rs`.) The file is
renamed from `rustc_mir_dataflow/src/elaborate_drops.rs` to
`rustc_mir_transform/src/elaborate_drop.rs` (with no trailing `s`)
because (a) the `elaborate_drop` function is the most important export,
and (b) `rustc_mir_transform/src/elaborate_drops.rs` already exists.
All the infrastructure pieces that used to be `pub` are now
`pub(crate)`, because they are now only used within
`rustc_mir_transform`.
coverage: Eliminate more counters by giving them to unreachable nodes
When preparing a function's coverage counters and metadata during codegen, any part of the original coverage graph that was removed by MIR optimizations can be treated as having an execution count of zero.
Somewhat counter-intuitively, if we give those unreachable nodes a _higher_ priority for receiving physical counters (instead of counter expressions), that ends up reducing the total number of physical counters needed.
This works because if a node is unreachable, we don't actually create a physical counter for it. Instead that node gets a fixed zero counter, and any other node that would have relied on that physical counter in its counter expression can just ignore that term completely.
debuginfo: Set bitwidth appropriately in enum variant tags
Previously, we unconditionally set the bitwidth to 128-bits, the largest an enum would possibly be. Then, LLVM would cut down the constant by chopping off leading zeroes before emitting the DWARF. LLVM only supported 64-bit enumerators, so this would also have occasionally resulted in truncated data.
LLVM added support for 128-bit enumerators in llvm/llvm-project#125578
That patchset trusts the constant to describe how wide the variant tag is, so the high 64-bits of zeros are considered potentially load-bearing.
As a result, we went from emitting tags that looked like:
DW_AT_discr_value (0xfe)
(because `dwarf::BestForm` selected `data1`)
to emitting tags that looked like:
DW_AT_discr_value (<0x10> fe ff ff ff 00 00 00 00 00 00 00 00 00 00 00 00 )
This makes the `DW_AT_discr_value` encode at the bitwidth of the tag, which:
1. Is probably closer to our intentions in terms of describing the data.
2. Doesn't invoke the 128-bit support which may not be supported by all debuggers / downstream tools.
3. Will result in smaller debug information.
valtree performance tuning
Summary: This PR makes type checking of code with many type-level constants faster.
After https://github.com/rust-lang/rust/pull/136180 was merged, we observed a small perf regression (https://github.com/rust-lang/rust/pull/136318#issuecomment-2635562821). This happened because that PR introduced additional copies in the fast reject code path for consts, which is very hot for certain crates: 6c1d960d88/compiler/rustc_type_ir/src/fast_reject.rs (L486-L487)
This PR improves the performance again by properly interning the valtrees so that copying and comparing them becomes faster. This will become especially useful with `feature(adt_const_params)`, so the fast reject code doesn't have to do a deep compare of the valtrees.
Note that we can't just compare the interned consts themselves in the fast reject, because sometimes `'static` lifetimes in the type are be replaced with inference variables (due to canonicalization) on one side but not the other.
A less invasive alternative that I considered is simply avoiding copies introduced by https://github.com/rust-lang/rust/pull/136180 and comparing the valtrees it in-place (see commit: 9e91e50ac5 / perf results: https://github.com/rust-lang/rust/pull/136593#issuecomment-2642303245), however that was still measurably slower than interning.
There are some minor regressions in secondary benchmarks: These happen due to changes in memory allocations and seem acceptable to me. The crates that make heavy use of valtrees show no significant changes in memory usage.
Rollup of 8 pull requests
Successful merges:
- #134999 (Add cygwin target.)
- #136559 (Resolve named regions when reporting type test failures in NLL)
- #136660 (Use a trait to enforce field validity for union fields + `unsafe` fields + `unsafe<>` binder types)
- #136858 (Parallel-compiler-related cleanup)
- #136881 (cg_llvm: Reduce visibility of all functions in the llvm module)
- #136888 (Always perform discr read for never pattern in EUV)
- #136948 (Split out the `extern_system_varargs` feature)
- #136949 (Fix import in bench for wasm)
r? `@ghost`
`@rustbot` modify labels: rollup
Split out the `extern_system_varargs` feature
After the stabilization PR was opened, `extern "system"` functions were added to `extended_varargs_abi_support`. This has a number of questions regarding it that were not discussed and were somewhat surprising. It deserves to be considered as its own feature, separate from `extended_varargs_abi_support`.
Tracking issue:
- https://github.com/rust-lang/rust/issues/136946
Always perform discr read for never pattern in EUV
Always perform a read of `!` discriminants to ensure that it's captured by closures in expr use visitor
Fixes#136852
r? Nadrieril or reassign
cg_llvm: Reduce visibility of all functions in the llvm module
Next part of #135502
This reduces the visibility of all functions in the `llvm` module to `pub(crate)` and marks the `enzyme_ffi` modules with `#![expect(dead_code)]` (as previously discussed: <https://github.com/rust-lang/rust/pull/135502#discussion_r1915608085>).
r? ``@Zalathar``
Parallel-compiler-related cleanup
Parallel-compiler-related cleanup
I carefully split changes into commits. Commit messages are self-explanatory. Squashing is not recommended.
cc "Parallel Rustc Front-end" https://github.com/rust-lang/rust/issues/113349
r? SparrowLii
``@rustbot`` label: +WG-compiler-parallel
Use a trait to enforce field validity for union fields + `unsafe` fields + `unsafe<>` binder types
This PR introduces a new, internal-only trait called `BikeshedGuaranteedNoDrop`[^1] to faithfully model the field check that used to be implemented manually by `allowed_union_or_unsafe_field`.
942db6782f/compiler/rustc_hir_analysis/src/check/check.rs (L84-L115)
Copying over the doc comment from the trait:
```rust
/// Marker trait for the types that are allowed in union fields, unsafe fields,
/// and unsafe binder types.
///
/// Implemented for:
/// * `&T`, `&mut T` for all `T`,
/// * `ManuallyDrop<T>` for all `T`,
/// * tuples and arrays whose elements implement `BikeshedGuaranteedNoDrop`,
/// * or otherwise, all types that are `Copy`.
///
/// Notably, this doesn't include all trivially-destructible types for semver
/// reasons.
///
/// Bikeshed name for now.
```
As far as I am aware, there's no new behavior being guaranteed by this trait, since it operates the same as the manually implemented check. We could easily rip out this trait and go back to using the manually implemented check for union fields, however using a trait means that this code can be shared by WF for `unsafe<>` binders too. See the last commit.
The only diagnostic changes are that this now fires false-negatives for fields that are ill-formed. I don't consider that to be much of a problem though.
r? oli-obk
[^1]: Please let's not bikeshed this name lol. There's no good name for `ValidForUnsafeFieldsUnsafeBindersAndUnionFields`.
Resolve named regions when reporting type test failures in NLL
Just a improvement tweak to an error message that I broke out of a bigger PR that I had to close lol
Previously it only did integer-ABI things, but this way it does data pointers too. That gives more information in general to the backend, and allows slightly simplifying one of the helpers in slice iterators.
After the stabilization PR was opened, `extern "system"` functions were
added to `extended_varargs_abi_support`. This has a number of questions
regarding it that were not discussed and were somewhat surprising.
It deserves to be considered as its own feature, separate from
`extended_varargs_abi_support`.
When preparing a function's coverage counters and metadata during codegen, any
part of the original coverage graph that was removed by MIR optimizations can
be treated as having an execution count of zero.
Somewhat counter-intuitively, if we give those unreachable nodes a _higher_
priority for receiving physical counters (instead of counter expressions), that
ends up reducing the total number of physical counters needed.
This works because if a node is unreachable, we don't actually create a
physical counter for it. Instead that node gets a fixed zero counter, and any
other node that would have relied on that physical counter in its counter
expression can just ignore that term completely.
Fix cycle when debug-printing opaque types from RPITIT
Extend #66594 to opaque types from RPITIT.
Before this PR, enabling debug logging like `RUSTC_LOG="[check_type_bounds]"` for code containing RPITIT produces a query cycle of `explicit_item_bounds`, as pretty printing for opaque type calls [it](d9a4a47b8b/compiler/rustc_middle/src/ty/print/pretty.rs (L1001)).
Mark condition/carry bit as clobbered in C-SKY inline assembly
C-SKY's compare and some arithmetic/logical instructions modify condition/carry bit (C) in PSR, but there is currently no way to mark it as clobbered in `asm!`.
This PR marks it as clobbered except when [`options(preserves_flags)`](https://doc.rust-lang.org/reference/inline-assembly.html#r-asm.options.supported-options.preserves_flags) is used.
Refs:
- Section 1.3 "Programming model" and Section 1.3.5 "Condition/carry bit" in CSKY Architecture user_guide:
9f7121f7d4/CSKY%20Architecture%20user_guide.pdf
> Under user mode, condition/carry bit (C) is located in the lowest bit of PSR, and it can be
accessed and changed by common user instructions. It is the only data bit that can be visited
under user mode in PSR.
> Condition or carry bit represents the result after one operation. Condition/carry bit can be
clearly set according to the results of compare instructions or unclearly set as some
high-precision arithmetic or logical instructions. In addition, special instructions such as
DEC[GT,LT,NE] and XTRB[0-3] will influence the value of condition/carry bit.
- Register definition in LLVM:
https://github.com/llvm/llvm-project/blob/llvmorg-19.1.0/llvm/lib/Target/CSKY/CSKYRegisterInfo.td#L88
cc ```@Dirreke``` ([target maintainer](aa6f5ab18e/src/doc/rustc/src/platform-support/csky-unknown-linux-gnuabiv2.md (target-maintainers)))
r? ```@Amanieu```
```@rustbot``` label +O-csky +A-inline-assembly
Reject `?Trait` bounds in various places where we unconditionally warned since 1.0
fixes#135730fixes#135809
Also a breaking change, so let's see what crater says.
This has been an unconditional warning since *before* 1.0
Cast allocas to default address space
Pointers for variables all need to be in the same address space for correct compilation. Therefore ensure that even if an `alloca` is created in a different address space, it is casted to the default address space before its value is used.
This is necessary for the amdgpu target and others where the default address space for `alloca`s is not 0.
For example the following code compiles incorrectly when not casting the address space to the default one:
```rust
fn f(p: *const i8 /* addrspace(0) */) -> *const i8 /* addrspace(0) */ {
let local = 0i8; /* addrspace(5) */
let res = if cond { p } else { &raw const local };
res
}
```
results in
```llvm
%local = alloca addrspace(5) i8
%res = alloca addrspace(5) ptr
if:
; Store 64-bit flat pointer
store ptr %p, ptr addrspace(5) %res
else:
; Store 32-bit scratch pointer
store ptr addrspace(5) %local, ptr addrspace(5) %res
ret:
; Load and return 64-bit flat pointer
%res.load = load ptr, ptr addrspace(5) %res
ret ptr %res.load
```
For amdgpu, `addrspace(0)` are 64-bit pointers, `addrspace(5)` are 32-bit pointers.
The above code may store a 32-bit pointer and read it back as a 64-bit pointer, which is obviously wrong and cannot work. Instead, we need to `addrspacecast %local to ptr addrspace(0)`, then we store and load the correct type.
Tracking issue: #135024
Stabilize target_feature_11
# Stabilization report
This is an updated version of https://github.com/rust-lang/rust/pull/116114, which is itself a redo of https://github.com/rust-lang/rust/pull/99767. Most of this commit and report were copied from those PRs. Thanks ```@LeSeulArtichaut``` and ```@calebzulawski!```
## Summary
Allows for safe functions to be marked with `#[target_feature]` attributes.
Functions marked with `#[target_feature]` are generally considered as unsafe functions: they are unsafe to call, cannot *generally* be assigned to safe function pointers, and don't implement the `Fn*` traits.
However, calling them from other `#[target_feature]` functions with a superset of features is safe.
```rust
// Demonstration function
#[target_feature(enable = "avx2")]
fn avx2() {}
fn foo() {
// Calling `avx2` here is unsafe, as we must ensure
// that AVX is available first.
unsafe {
avx2();
}
}
#[target_feature(enable = "avx2")]
fn bar() {
// Calling `avx2` here is safe.
avx2();
}
```
Moreover, once https://github.com/rust-lang/rust/pull/135504 is merged, they can be converted to safe function pointers in a context in which calling them is safe:
```rust
// Demonstration function
#[target_feature(enable = "avx2")]
fn avx2() {}
fn foo() -> fn() {
// Converting `avx2` to fn() is a compilation error here.
avx2
}
#[target_feature(enable = "avx2")]
fn bar() -> fn() {
// `avx2` coerces to fn() here
avx2
}
```
See the section "Closures" below for justification of this behaviour.
## Test cases
Tests for this feature can be found in [`tests/ui/target_feature/`](f6cb952dc1/tests/ui/target-feature).
## Edge cases
### Closures
* [target-feature 1.1: should closures inherit target-feature annotations? #73631](https://github.com/rust-lang/rust/issues/73631)
Closures defined inside functions marked with #[target_feature] inherit the target features of their parent function. They can still be assigned to safe function pointers and implement the appropriate `Fn*` traits.
```rust
#[target_feature(enable = "avx2")]
fn qux() {
let my_closure = || avx2(); // this call to `avx2` is safe
let f: fn() = my_closure;
}
```
This means that in order to call a function with #[target_feature], you must guarantee that the target-feature is available while the function, any closures defined inside it, as well as any safe function pointers obtained from target-feature functions inside it, execute.
This is usually ensured because target features are assumed to never disappear, and:
- on any unsafe call to a `#[target_feature]` function, presence of the target feature is guaranteed by the programmer through the safety requirements of the unsafe call.
- on any safe call, this is guaranteed recursively by the caller.
If you work in an environment where target features can be disabled, it is your responsibility to ensure that no code inside a target feature function (including inside a closure) runs after this (until the feature is enabled again).
**Note:** this has an effect on existing code, as nowadays closures do not inherit features from the enclosing function, and thus this strengthens a safety requirement. It was originally proposed in #73631 to solve this by adding a new type of UB: “taking a target feature away from your process after having run code that uses that target feature is UB” .
This was motivated by userspace code already assuming in a few places that CPU features never disappear from a program during execution (see i.e. 2e29bdf908/crates/std_detect/src/detect/arch/x86.rs); however, concerns were raised in the context of the Linux kernel; thus, we propose to relax that requirement to "causing the set of usable features to be reduced is unsafe; when doing so, the programmer is required to ensure that no closures or safe fn pointers that use removed features are still in scope".
* [Fix #[inline(always)] on closures with target feature 1.1 #111836](https://github.com/rust-lang/rust/pull/111836)
Closures accept `#[inline(always)]`, even within functions marked with `#[target_feature]`. Since these attributes conflict, `#[inline(always)]` wins out to maintain compatibility.
### ABI concerns
* [The extern "C" ABI of SIMD vector types depends on target features #116558](https://github.com/rust-lang/rust/issues/116558)
The ABI of some types can change when compiling a function with different target features. This could have introduced unsoundness with target_feature_11, but recent fixes (#133102, #132173) either make those situations invalid or make the ABI no longer dependent on features. Thus, those issues should no longer occur.
### Special functions
The `#[target_feature]` attribute is forbidden from a variety of special functions, such as main, current and future lang items (e.g. `#[start]`, `#[panic_handler]`), safe default trait implementations and safe trait methods.
This was not disallowed at the time of the first stabilization PR for target_features_11, and resulted in the following issues/PRs:
* [`#[target_feature]` is allowed on `main` #108645](https://github.com/rust-lang/rust/issues/108645)
* [`#[target_feature]` is allowed on default implementations #108646](https://github.com/rust-lang/rust/issues/108646)
* [#[target_feature] is allowed on #[panic_handler] with target_feature 1.1 #109411](https://github.com/rust-lang/rust/issues/109411)
* [Prevent using `#[target_feature]` on lang item functions #115910](https://github.com/rust-lang/rust/pull/115910)
## Documentation
* Reference: [Document the `target_feature_11` feature reference#1181](https://github.com/rust-lang/reference/pull/1181)
---
cc tracking issue https://github.com/rust-lang/rust/issues/69098
cc ```@workingjubilee```
cc ```@RalfJung```
r? ```@rust-lang/lang```
Rename rustc_middle::Ty::is_unsafe_ptr to is_raw_ptr
The wording unsafe pointer is less common and not mentioned in a lot of places, instead this is usually called a "raw pointer". For the sake of uniformity, we rename this method.
This came up during the review of
https://github.com/rust-lang/rust/pull/134424.
r? `@Noratrieb`
The host runtime (HIP or HSA) expects a kernel descriptor object for
each kernel in the ELF file. The amdgpu LLVM backend generates the
object. It is created as a symbol with the name of the kernel plus a
`.kd` suffix.
Add it to the exported symbols in the linker script, so that it can be
found.
compiler: give `ExternAbi` truly stable `Hash` and `Ord`
Currently, `ExternAbi` has a bunch of code to handle the reality that, as an enum, adding more variants to it will risk it hashing differently. It forces all of those variants to be added in a fixed order, except this means that the order of the variants doesn't correspond to any logical order except "historical accident". This is all to avoid having to rebless two tests. Perhaps there were more, once upon a time? But then we invented normalization in our test suite to handle exactly this sort of issue in a more general way.
There are two options here:
- Get rid of all the logical overhead and shrug, embracing blessing a couple of tests sometimes
- Change `ExternAbi` to have an ordering and hash that doesn't depend on the number of variants
As `ExternAbi` is essentially a strongly-typed string, and thus no two strings can be identical, this implements the second of the two by hand-implementing `Ord` and `Hash` to make the hashing and comparison based on the string! This will diff the current hashes, but they will diff no more after this.
Previously, we unconditionally set the bitwidth to 128-bits, the largest
an discrimnator would possibly be. Then, LLVM would cut down the constant by
chopping off leading zeroes before emitting the DWARF. LLVM only
supported 64-bit descriminators, so this would also have occasionally
resulted in truncated data (or an assert) if more than 64-bits were
used.
LLVM added support for 128-bit enumerators in llvm/llvm-project#125578
That patchset also trusts the constant to describe how wide the variant tag is.
As a result, we went from emitting tags that looked like:
DW_AT_discr_value (0xfe)
(`form1`)
to emitting tags that looked like:
DW_AT_discr_value (<0x10> fe ff ff ff 00 00 00 00 00 00 00 00 00 00 00 00 )
This makes the `DW_AT_discr_value` encode at the bitwidth of the tag,
which:
1. Is probably closer to our intentions in terms of describing the data.
2. Doesn't invoke the 128-bit support which may not be supported by all
debuggers / downstream tools.
3. Will result in smaller debug information.
Rollup of 8 pull requests
Successful merges:
- #134981 ( Explain that in paths generics can't be set on both the enum and the variant)
- #136698 (Replace i686-unknown-redox target with i586-unknown-redox)
- #136767 (improve host/cross target checking)
- #136829 ([rustdoc] Move line numbers into the `<code>` directly)
- #136875 (Rustc dev guide subtree update)
- #136900 (compiler: replace `ExternAbi::name` calls with formatters)
- #136913 (Put kobzol back on review rotation)
- #136915 (documentation fix: `f16` and `f128` are not double-precision)
r? `@ghost`
`@rustbot` modify labels: rollup
compiler: replace `ExternAbi::name` calls with formatters
Most of these just format the ABI string, so... just format ExternAbi? This makes it more consistent and less jank when we can do it.
Explain that in paths generics can't be set on both the enum and the variant
```
error[E0109]: type arguments are not allowed on tuple variant `TSVariant`
--> $DIR/enum-variant-generic-args.rs:54:29
|
LL | Enum::<()>::TSVariant::<()>(());
| --------- ^^ type argument not allowed
| |
| not allowed on tuple variant `TSVariant`
|
= note: generic arguments are not allowed on both an enum and its variant's path segments simultaneously; they are only valid in one place or the other
help: remove the generics arguments from one of the path segments
|
LL - Enum::<()>::TSVariant::<()>(());
LL + Enum::TSVariant::<()>(());
|
LL - Enum::<()>::TSVariant::<()>(());
LL + Enum::<()>::TSVariant(());
|
```
Fix#93993.
Rollup of 8 pull requests
Successful merges:
- #135549 (Document some safety constraints and use more safe wrappers)
- #135965 (In "specify type" suggestion, skip type params that are already known)
- #136193 (Implement pattern type ffi checks)
- #136646 (Add a TyPat in the AST to reuse the generic arg lowering logic)
- #136874 (Change the issue number for `likely_unlikely` and `cold_path`)
- #136884 (Lower fn items as ZST valtrees and delay a bug)
- #136885 (i686-linux-android: increase CPU baseline to Pentium 4 (without an actual change)
- #136891 (Check sig for errors before checking for unconstrained anonymous lifetime)
r? `@ghost`
`@rustbot` modify labels: rollup
i686-linux-android: increase CPU baseline to Pentium 4 (without an actual change
As per ``@maurer's`` [comment](https://github.com/rust-lang/rust/issues/136495#issuecomment-2648743078), this shouldn't actually change anything since we anyway add a bunch of extensions that bump things up way beyond Pentium 4. But Pentium 4 is consistent with the other i686 targets and I don't know enough about the exact sequence of CPU generations to be confident with more than this. ;)
Lower fn items as ZST valtrees and delay a bug
Lower it as a ZST instead of a const error, which we can handle mostly fine. Delay a bug so we don't accidentally support it tho.
r? BoxyUwU
Fixes#136855Fixes#136853Fixes#136854Fixes#136337
Only added one test bc that's really the crux of the issue (fn item in array length position).
Add a TyPat in the AST to reuse the generic arg lowering logic
This simplifies ast lowering significantly with little cost to the pattern types parser.
Also fixes any problems we've had with generic args (well, pushes any problems onto the `generic_const_exprs` feature gate)
follow-up to https://github.com/rust-lang/rust/pull/136284#discussion_r1939292367
r? ``@BoxyUwU``
Implement pattern type ffi checks
Previously we just rejected pattern types outright in FFI, but that was never meant to be a permanent situation. We'll need them supported to use them as the building block for `NonZero` and `NonNull` after all (both of which are FFI safe).
best reviewed commit by commit.
In "specify type" suggestion, skip type params that are already known
When we suggest specifying a type for an expression or pattern, like in a `let` binding, we previously would print the entire type as the type system knew it. We now look at the params that have *no* inference variables, so they are fully known to the type system which means that they don't need to be specified.
This helps in suggestions for types that are really long, because we can usually skip most of the type params and make the annotation as short as possible:
```
error[E0282]: type annotations needed for `Result<_, ((..., ..., ..., ...), ..., ..., ...)>`
--> $DIR/really-long-type-in-let-binding-without-sufficient-type-info.rs:7:9
|
LL | let y = Err(x);
| ^ ------ type must be known at this point
|
help: consider giving `y` an explicit type, where the type for type parameter `T` is specified
|
LL | let y: Result<T, _> = Err(x);
| ++++++++++++++
```
Fix#135919.
Document some safety constraints and use more safe wrappers
Lots of unsafe codegen_llvm code has safe wrappers already, so I used some of them and added some where applicable. I stopped here because this diff is large enough and should probably be reviewed independently of other changes.
These were a way to ensure hashes were stable over time for ExternAbi,
but simply hashing the strings is more stable in the face of changes.
As a result, we can do away with them.
Directly map each ExternAbi variant to its string and back again.
This has a few advantages:
- By making the ABIs compare equal to their strings, we can easily
lexicographically sort them and use that sorted slice at runtime.
- We no longer need a workaround to make sure the hashes remain stable,
as they already naturally are (by being the hashes of unique strings).
- The compiler can carry around less &str wide pointers
Properly deeply normalize in the next solver
Turn deep normalization into a `TypeOp`. In the old solver, just dispatch to the `Normalize` type op, but in the new solver call `deeply_normalize`. I chose to separate it into a different type op b/c some normalization is a no-op in the new solver, so this distinguishes just the normalization we need for correctness.
Then use `DeeplyNormalize` in the callsites we used to be using a `CustomTypeOp` (for normalizing known type outlives obligations), and also use it to normalize function args and impl headers in the new solver.
Finally, use it to normalize signatures for WF checks in the new solver as well. This addresses https://github.com/rust-lang/trait-system-refactor-initiative/issues/146.
```
error[E0109]: type arguments are not allowed on tuple variant `TSVariant`
--> $DIR/enum-variant-generic-args.rs:54:29
|
LL | Enum::<()>::TSVariant::<()>(());
| --------- ^^ type argument not allowed
| |
| not allowed on tuple variant `TSVariant`
|
= note: generic arguments are not allowed on both an enum and its variant's path segments simultaneously; they are only valid in one place or the other
help: remove the generics arguments from one of the path segments
|
LL - Enum::<()>::TSVariant::<()>(());
LL + Enum::<()>::TSVariant(());
|
```
```
error[E0109]: type arguments are not allowed on enum `Enum` and tuple variant `TSVariant`
--> $DIR/enum-variant-generic-args.rs:54:12
|
LL | Enum::<()>::TSVariant::<()>(());
| ---- ^^ --------- ^^ type argument not allowed
| | |
| | not allowed on tuple variant `TSVariant`
| not allowed on enum `Enum`
|
= note: generic arguments are not allowed on both an enum and its variant's path segments simultaneously; they are only valid in one place or the other
help: remove the generics arguments from one of the path segments
|
LL - Enum::<()>::TSVariant::<()>(());
LL + Enum::<()>::TSVariant(());
|
```
Fix#93993.
Simplify intra-crate qualifiers.
The following is a weird pattern for a file within `rustc_middle`:
```
use rustc_middle::aaa;
use crate::bbb;
```
More sensible and standard would be this:
```
use crate::{aaa, bbb};
```
I.e. we generally prefer using `crate::` to using a crate's own name. (Exceptions are things like in macros where `crate::` doesn't work because the macro is used in multiple crates.)
This commit fixes a bunch of these weird qualifiers.
r? `@jieyouxu`
compiler: die immediately instead of handling unknown target codegen
We cannot produce anything useful if asked to compile unknown targets. We should handle the error immediately at the point of discovery instead of propagating it upward, and preferably in the simplest way: Die.
This allows cleaning up our "error-handling" spread across 5 crates.
show supported register classes in error message
a simple diagnostic change that shows the supported register classes when an invalid one is found.
This information can be hard to find (especially for unstable targets), and this message now gives at least something to try or search for. I've followed the pattern for invalid clobber ABIs.
`@rustbot` label +A-inline-assembly
fix ensure_monomorphic_enough
When polymorphization was still a thing, the visitor was used to only recurse into *used generic parameters* of function/closure/coroutine types and allow unused parameters (i.e. the polymorphized parameters) to remain generic.
When polymorphization got removed, this got changed to always treat all parameters as polymorphic and never recurse into them: https://github.com/rust-lang/rust/pull/133883/files#diff-210c59e321070d0ca4625c04e9fb064bf43ddc34082e7e33a7ee8a6c577e95afL44-L62
This is clearly wrong and can cause MIR opts to misbehave, for example this currently prints "false" in release mode:
```rust
#![feature(core_intrinsics)]
fn generic<T>() {}
const fn type_id_of_val<T: 'static>(_: &T) -> u128 {
std::intrinsics::type_id::<T>()
}
fn cursed_is_i32<T: 'static>() -> bool {
(const { type_id_of_val(&generic::<T>) } == const { type_id_of_val(&generic::<i32>) })
}
fn main() {
dbg!(cursed_is_i32::<i32>());
}
```
This PR reverts to the old behavior of always treating all types that contain type parameters as too generic, like we used to do without `-Zpolymorphize` before.
~~I'm not including the above as a test case here, because I think there is little value in testing code paths that have been removed and this seems unlikely to regress in a way that would be caught by a regression test, but let me know if you disagree and want me to add a test anyway.~~
Overhaul how contracts are lowered on fn-like bodies
Consolidates all of the contracts lowering logic into `lower_fn_body`, rather than having it be split between `lower_item_kind` and `lower_fn_body`. This should fix#136683.
r? celinval
Stop using span hack for contracts feature gating
The contracts machinery is a pretty straightforward case of an *external* feature using a (perma-unstable) *internal* feature within its implementation. There's no reason why it needs to be implemented any differently than other features by using global span tracking hacks to change whether the internals are gated behind the `contracts` or `contracts_internals` feature gate -- for the case of macro expansions we already have `allow_internal_unstable` for exactly this situation.
This PR changes the internal, perma-unstable AST syntax to use the `contracts_internals` gate always, and adjusts the macro expansion to use the right spans so that `allow_internal_unstable` works correctly.
As a follow-up, there's really no reason to have `contracts` be a *compiler feature* since it's at this point fully a *library feature*; the only reason it's a compiler feature today is so we can mark it as incomplete, but that seems like a weak reason. I didn't do anything in this PR for this.
r? ``@celinval``
cg_llvm: Reduce visibility of some items outside the `llvm` module
Next piece of #135502
This reduces the visibility of items (other than those in the `llvm` module) so that dead code analysis will correctly identify unused items.
The following is a weird pattern for a file within `rustc_middle`:
```
use rustc_middle::aaa;
use crate::bbb;
```
More sensible and standard would be this:
```
use crate::{aaa, bbb};
```
I.e. we generally prefer using `crate::` to using a crate's own name.
(Exceptions are things like in macros where `crate::` doesn't work
because the macro is used in multiple crates.)
This commit fixes a bunch of these weird qualifiers.
Show diff suggestion format on verbose replacement
```
error[E0610]: `{integer}` is a primitive type and therefore doesn't have fields
--> $DIR/attempted-access-non-fatal.rs:7:15
|
LL | let _ = 2.l;
| ^
|
help: if intended to be a floating point literal, consider adding a `0` after the period and a `f64` suffix
|
LL - let _ = 2.l;
LL + let _ = 2.0f64;
|
```
before:
```
error[E0610]: `{integer}` is a primitive type and therefore doesn't have fields
--> $DIR/attempted-access-non-fatal.rs:7:15
|
LL | let _ = 2.l;
| ^
|
help: if intended to be a floating point literal, consider adding a `0` after the period and a `f64` suffix
|
LL + let _ = 2.0f64;
| ~~~~
```
r? `@oli-obk`
compiler: gate `extern "{abi}"` in ast_lowering
I don't believe low-level crates like `rustc_abi` should have to know or care about higher-level concerns like whether the ABI string is stable for users. These implementation details can be made less open to public inspection. This way the code that governs stability is near the code that enforces stability, and compiled together.
It also abstracts away certain error messages instead of constantly repeating them.
A few error messages are simply deleted outright, instead of made uniform, because they are either too dated to be useful or redundant with other diagnostic improvements we could make. These can be pursued in followups: my first concern was making sure there wasn't unnecessary diagnostics-related code in `rustc_abi`, which is not well-positioned to understand what kind of errors are going to be generated based on how it is used.
r? ``@ghost``
Prevent generic pattern types from being used in libstd
Pattern types should follow the same rules that patterns follow. So a pattern type range must not wrap and not be empty. While we reject such invalid ranges at layout computation time, that only happens during monomorphization in the case of const generics. This is the exact same issue as other const generic math has, and since there's no solution there yet, I put these pattern types behind a separate incomplete feature.
These are not necessary for the pattern types MVP (replacing the layout range attributes in libcore and rustc).
cc #136574 (new tracking issue for the `generic_pattern_types` feature gate)
r? ``@lcnr``
cc ``@scottmcm`` ``@joshtriplett``
Delay bug when method confirmation cannot upcast object pick of self
Justification is on the test comment. Simply delays a bug that we were previously ICEing on.
cc ``@adetaylor`` since this is a `arbitrary_self_types` ICE.
Introduce CoercePointeeWellformed for coherence checks at typeck stage
Fix#135206
This is the first PR to introduce the "wellformedness" check for `derive(CoercePointee)`.
This patch introduces a new error code to cover all the prerequisites of the said macro. The checks that is enforced with this patch is whether the data is indeed `struct` and whether the layout is set to `repr(transparent)`.
A following series of patch will arrive later to address the following concern.
1. #135217 so that we would only admit one single coercion on one type parameter, and leave the rest for future consideration in tandem of development of other coercion rules.
1. Enforcement of data field requirements.
**An open question** is whether there is a good schema to encode the `#[pointee]` as well, so that we could also check if the `#[pointee]` type parameter is indeed `?Sized`.
``@rustbot`` label F-derive_coerce_pointee
Pointers for variables all need to be in the same address space for
correct compilation. Therefore ensure that even if an `alloca` is
created in a different address space, it is casted to the default
address space before its value is used.
This is necessary for the amdgpu target and others where the default
address space for `alloca`s is not 0.
For example the following code compiles incorrectly when not casting the
address space to the default one:
```rust
fn f(p: *const i8 /* addrspace(0) */) -> *const i8 /* addrspace(0) */ {
let local = 0i8; /* addrspace(5) */
let res = if cond { p } else { &raw const local };
res
}
```
results in
```llvm
%local = alloca addrspace(5) i8
%res = alloca addrspace(5) ptr
if:
; Store 64-bit flat pointer
store ptr %p, ptr addrspace(5) %res
else:
; Store 32-bit scratch pointer
store ptr addrspace(5) %local, ptr addrspace(5) %res
ret:
; Load and return 64-bit flat pointer
%res.load = load ptr, ptr addrspace(5) %res
ret ptr %res.load
```
For amdgpu, `addrspace(0)` are 64-bit pointers, `addrspace(5)` are
32-bit pointers.
The above code may store a 32-bit pointer and read it back as a 64-bit
pointer, which is obviously wrong and cannot work. Instead, we need to
`addrspacecast %local to ptr addrspace(0)`, then we store and load the
correct type.
```
error[E0610]: `{integer}` is a primitive type and therefore doesn't have fields
--> $DIR/attempted-access-non-fatal.rs:7:15
|
LL | let _ = 2.l;
| ^
|
help: if intended to be a floating point literal, consider adding a `0` after the period and a `f64` suffix
|
LL - let _ = 2.l;
LL + let _ = 2.0f64;
|
```
We cannot produce anything useful if asked to compile unknown targets.
We should handle the error immediately at the point of discovery instead
of propagating it upward, and preferably in the simplest way: Die.
This allows cleaning up our "error-handling" spread across 5 crates.
Disable DWARF in linker options for i686-unknown-uefi
This fixes an lld warning:
> warning: linker stderr: rust-lld: section name .debug_frame is longer than 8 characters and will use a non-standard string table
See https://reviews.llvm.org/D69594 for details of where the warning was added.
This warning only occurs with the i686 UEFI target, not x86_64 or aarch64. The x86_64 target uses an LLVM target of
`x86_64-unknown-windows` and aarch64 uses `aarch64-unknown-windows`, but i686 uses `i686-unknown-windows-gnu` (note the `-gnu`). See comments in `i686_unknown_uefi.rs` for details of why.
The `.debug_frame` section should not actually be needed; UEFI targets provide a separate PDB file for debugging. Disable DWARF (and by extension the `.debug_frame` section) by passing `/DEBUG:NODWARF` to lld.
Tested with:
```
export RUSTC_LOG=rustc_codegen_ssa:🔙:link=info
cargo +stage1 build --release --target i686-unknown-uefi
```
This issue was originally raised here: https://github.com/rust-lang/rust/pull/119286#issuecomment-2612746162. See also https://github.com/rust-lang/rust/issues/136096. It was suggested to file an LLVM bug, but I don't think LLVM is actually doing anything wrong as such.
CC `@dvdhrm` `@jyn514` let me know if you have any feedback on this approach
rustc_middle: parallel: TyCtxt: remove "unsafe impl DynSend/DynSync"
rustc_middle: parallel: TyCtxt: remove "unsafe impl DynSend/DynSync"
We don't need to "short circuit trait resolution", because DynSend and DynSync are auto traits and thus coinductive
cc "Parallel Rustc Front-end" https://github.com/rust-lang/rust/issues/113349
r? SparrowLii
``@rustbot`` label: +WG-compiler-parallel
(rustbot sometimes ignores me and doesn't attach labels on my behalf. rustbot banned me?)
adding autodiff tests
I'd like to get started with upstreaming some tests, even though I'm still waiting for an answer on how to best integrate the enzyme pass. Can we therefore temporarily support the -Z llvm-plugins here without too much effort? And in that case, how would that work? I saw you can do remapping, e.g. `rust-src-base`, but I don't think that will give me the path to libEnzyme.so. Do you have another suggestion?
Other than that this test simply checks that the derivative of `x*x` is `2.0 * x`, which in this case is computed as
`%0 = fadd fast double %x.0.val, %x.0.val`
(I'll add a few more tests and move it to an autodiff folder if we can use the -Z flag)
r? ``@jieyouxu``
Locally at least `-Zllvm-plugins=${PWD}/build/x86_64-unknown-linux-gnu/enzyme/build/Enzyme/libEnzyme-19.so` seems to work if I copy the command I get from x.py test and run it manually. However, running x.py test itself fails.
Tracking:
- https://github.com/rust-lang/rust/issues/124509
Zulip discussion: https://rust-lang.zulipchat.com/#narrow/channel/326414-t-infra.2Fbootstrap/topic/Enzyme.20build.20changes
The wording unsafe pointer is less common and not mentioned in a lot of
places, instead this is usually called a "raw pointer". For the sake of
uniformity, we rename this method.
This came up during the review of
https://github.com/rust-lang/rust/pull/134424.
Removed dependency on the field-offset crate, alternate approach
This is an alternate approach to reach the same goals as #136003. As it touches the core of the query system, this too probably should be evaluated for performance.
r? ``@Mark-Simulacrum``
coverage: Defer part of counter-creation until codegen
Follow-up to #135481 and #135873.
One of the pleasant properties of the new counter-assignment algorithm is that we can stop partway through the process, store the intermediate state in MIR, and then resume the rest of the algorithm during codegen. This lets it take into account which parts of the control-flow graph were eliminated by MIR opts, resulting in fewer physical counters and simpler counter expressions.
Those improvements end up completely obsoleting much larger chunks of code that were previously responsible for cleaning up the coverage metadata after MIR opts, while also doing a more thorough cleanup job.
(That change also unlocks some further simplifications that I've kept out of this PR to limit its scope.)
It is speculated that these two can be conceptually merged, and it can
start by ripping out rustc's notion of the PtxKernel call convention.
Leave the ExternAbi for now, but the nvptx target now should see it as
just a different way to spell Conv::GpuKernel.
