stabilize combining +bundle and +whole-archive link modifiers
Per discussion on https://github.com/rust-lang/rust/issues/108081 combining +bundle and +whole-archive already works and can be stabilized independently of other aspects of the packed_bundled_libs feature. There is no risk of regression because this was not previously allowed.
r? `@petrochenkov`
Reveal opaque types before drop elaboration
fixes https://github.com/rust-lang/rust/issues/113594
r? `@cjgillot`
cc `@JakobDegen`
This pass was introduced in https://github.com/rust-lang/rust/pull/110714
I moved it before drop elaboration (which only cares about the hidden types of things, not the opaque TAIT or RPIT type) and set it to run unconditionally (instead of depending on the optimization level and whether the inliner is active)
Make `adt_const_params` feature suggestion consistent with other features and improve when it is emitted
Makes the suggestion to add `adt_const_params` formatted like every other feature gate (notably this makes it such that the playground recognizes it). Additionally improves the situations in which that help is emitted so that it's only emitted when the type would be valid or the type *could* be valid (using a slightly incorrect heuristic that favors suggesting the feature over not) instead of, for example, implying that adding the feature would allow the use of `String`.
Also adds the "the only supported types are integers, `bool` and `char`" note to the errors on fn and raw pointers.
r? `@compiler-errors`
Fix `noop_method_call` detection
This needs to be merged before #116198 can compile. The error occurs before the compiler is built so this needs to be a separate PR.
new solver: remove provisional cache
The provisional cache is a performance optimization if there are large, interleaving cycles. Such cycles generally do not exist. It is incredibly complex and unsound in all trait solvers which have one: the old solver, chalk, and the new solver ([link](https://github.com/rust-lang/rust/blob/master/tests/ui/traits/new-solver/cycles/inductive-not-on-stack.rs)).
Given the assumption that it is not perf-critical and also incredibly complex, remove it from the new solver, only checking whether a goal is on the stack. While writing this, I uncovered two additional soundness bugs, see the inline comments for them.
r? `@compiler-errors`
Mitigate part of #71209.
```
error[E0308]: mismatched types
--> $DIR/unboxed-closures-type-mismatch.rs:30:18
|
LL | identity(1u16);
| -------- ^^^^ expected `u8`, found `u16`
| |
| arguments to this function are incorrect
|
note: expected because the closure was earlier called with an argument of type `u8`
--> $DIR/unboxed-closures-type-mismatch.rs:29:18
|
LL | identity(1u8);
| -------- ^^^ expected because this argument is of type `u8`
| |
| in this closure call
note: closure parameter defined here
--> $DIR/unboxed-closures-type-mismatch.rs:28:25
|
LL | let identity = |x| x;
| ^
help: change the type of the numeric literal from `u16` to `u8`
|
LL | identity(1u8);
| ~~
```
Stabilize `impl_trait_projections`
Closes#115659
## TL;DR:
This allows us to mention `Self` and `T::Assoc` in async fn and return-position `impl Trait`, as you would expect you'd be able to.
Some examples:
```rust
#![feature(return_position_impl_trait_in_trait, async_fn_in_trait)]
// (just needed for final tests below)
// ---------------------------------------- //
struct Wrapper<'a, T>(&'a T);
impl Wrapper<'_, ()> {
async fn async_fn() -> Self {
//^ Previously rejected because it returns `-> Self`, not `-> Wrapper<'_, ()>`.
Wrapper(&())
}
fn impl_trait() -> impl Iterator<Item = Self> {
//^ Previously rejected because it mentions `Self`, not `Wrapper<'_, ()>`.
std::iter::once(Wrapper(&()))
}
}
// ---------------------------------------- //
trait Trait<'a> {
type Assoc;
fn new() -> Self::Assoc;
}
impl Trait<'_> for () {
type Assoc = ();
fn new() {}
}
impl<'a, T: Trait<'a>> Wrapper<'a, T> {
async fn mk_assoc() -> T::Assoc {
//^ Previously rejected because `T::Assoc` doesn't mention `'a` in the HIR,
// but ends up resolving to `<T as Trait<'a>>::Assoc`, which does rely on `'a`.
// That's the important part -- the elided trait.
T::new()
}
fn a_few_assocs() -> impl Iterator<Item = T::Assoc> {
//^ Previously rejected for the same reason
[T::new(), T::new(), T::new()].into_iter()
}
}
// ---------------------------------------- //
trait InTrait {
async fn async_fn() -> Self;
fn impl_trait() -> impl Iterator<Item = Self>;
}
impl InTrait for &() {
async fn async_fn() -> Self { &() }
//^ Previously rejected just like inherent impls
fn impl_trait() -> impl Iterator<Item = Self> {
//^ Previously rejected just like inherent impls
[&()].into_iter()
}
}
```
## Technical:
Lifetimes in return-position `impl Trait` (and `async fn`) are duplicated as early-bound generics local to the opaque in order to make sure we are able to substitute any late-bound lifetimes from the function in the opaque's hidden type. (The [dev guide](https://rustc-dev-guide.rust-lang.org/return-position-impl-trait-in-trait.html#aside-opaque-lifetime-duplication) has a small section about why this is necessary -- this was written for RPITITs, but it applies to all RPITs)
Prior to #103491, all of the early-bound lifetimes not local to the opaque were replaced with `'static` to avoid issues where relating opaques caused their *non-captured* lifetimes to be related. This `'static` replacement led to strange and possibly unsound behaviors (https://github.com/rust-lang/rust/issues/61949#issuecomment-508836314) (https://github.com/rust-lang/rust/issues/53613) when referencing the `Self` type alias in an impl or indirectly referencing a lifetime parameter via a projection type (via a `T::Assoc` projection without an explicit trait), since lifetime resolution is performed on the HIR, when neither `T::Assoc`-style projections or `Self` in impls are expanded.
Therefore an error was implemented in #62849 to deny this subtle behavior as a known limitation of the compiler. It was attempted by `@cjgillot` to fix this in #91403, which was subsequently unlanded. Then it was re-attempted to much success (🎉) in #103491, which is where we currently are in the compiler.
The PR above (#103491) fixed this issue technically by *not* replacing the opaque's parent lifetimes with `'static`, but instead using variance to properly track which lifetimes are captured and are not. The PR gated any of the "side-effects" of the PR behind a feature gate (`impl_trait_projections`) presumably to avoid having to involve T-lang or T-types in the PR as well. `@cjgillot` can clarify this if I'm misunderstanding what their intention was with the feature gate.
Since we're not replacing (possibly *invariant*!) lifetimes with `'static` anymore, there are no more soundness concerns here. Therefore, this PR removes the feature gate.
Tests:
* `tests/ui/async-await/feature-self-return-type.rs`
* `tests/ui/impl-trait/feature-self-return-type.rs`
* `tests/ui/async-await/issues/issue-78600.rs`
* `tests/ui/impl-trait/capture-lifetime-not-in-hir.rs`
---
r? cjgillot on the impl (not much, just removing the feature gate)
I'm gonna mark this as FCP for T-lang and T-types.
Simplify some of the logic in the `invalid_reference_casting` lint
This PR simplifies 2 areas of the logic for the `invalid_reference_casting` lint:
- The init detection: we now use the newly added `expr_or_init` function instead of a manual detection
- The ref-to-mut-ptr casting detection logic: I simplified this logic by caring less hardly about the order of the casting operations
Those two simplifications permits us to detect more cases, as can be seen in the test output changes.
Implement a global value numbering MIR optimization
The aim of this pass is to avoid repeated computations by reusing past assignments. It is based on an analysis of SSA locals, in order to perform a restricted form of common subexpression elimination.
By opportunity, this pass allows for some simplifications by combining assignments. For instance, this pass could be able to see through projections of aggregates to directly reuse the aggregate field (not in this PR).
We handle references by assigning a different "provenance" index to each `Ref`/`AddressOf` rvalue. This ensure that we do not spuriously merge borrows that should not be merged. Meanwhile, we consider all the derefs of an immutable reference to a freeze type to give the same value:
```rust
_a = *_b // _b is &Freeze
_c = *_b // replaced by _c = _a
```
Anonymize binders for `refining_impl_trait` check
We're naively using the equality impl for `ty::Clause` in the refinement check, which is okay *except* for binders, which carry some information about where they come from in the AST. Those locations are not gonna be equal between traits and impls, so anonymize those clauses so that this doesn't matter.
Fixes#116135
Split out the stable part of smir into its own crate to prevent accidental usage of forever unstable things
Some groundwork for being able to work on https://github.com/rust-lang/project-stable-mir/issues/27 at all
r? `@spastorino`
Don't store lazyness in `DefKind::TyAlias`
1. Don't store lazyness of a type alias in its `DefKind`, but instead via a query.
2. This allows us to treat type aliases as lazy if `#[feature(lazy_type_alias)]` *OR* if the alias contains a TAIT, rather than having checks for both in separate parts of the codebase.
r? `@oli-obk` cc `@fmease`
Only prevent field projections into opaque types, not types containing opaque types
fixes https://github.com/rust-lang/rust/issues/115778
I did not think that original condition through properly... I'll also need to check the similar check around the other `ProjectionKind::OpaqueCast` creation site (this one is in hir, the other one is in mir), but I'll do that change in another PR that doesn't go into a beta backport.
Gate and validate `#[rustc_safe_intrinsic]`
Copied over from #116159:
> This was added as ungated in https://github.com/rust-lang/rust/pull/100719/files#diff-09c366d3ad3ec9a42125253b610ca83cad6b156aa2a723f6c7e83eddef7b1e8fR502, probably because the author looked at the surrounding attributes, which are ungated because they are gated specially behind the staged_api feature.
>
> I don't think we need to crater this, the attribute is entirely useless without the intrinsics feature, which is already unstable..
r? ``@Nilstrieb``
lint towards rejecting consts in patterns that do not implement PartialEq
I think we definitely don't want to allow such consts, so even while the general plan around structural matching is up in the air, we can start the process of getting non-PartialEq matches out of the ecosystem.
ConstParamTy: require Eq as supertrait
As discussed with `@BoxyUwu` [on Zulip](https://rust-lang.zulipchat.com/#narrow/stream/260443-project-const-generics/topic/.60ConstParamTy.60.20and.20.60Eq.60).
We want to say that valtree equality on const generic params agrees with `==`, but that only makes sense if `==` actually exists, hence we should have an appropriate bound. Valtree equality is an equivalence relation, so such a type can always be `Eq` and not just `PartialEq`.
Properly print cstr literals in `proc_macro::Literal::to_string`
Previously we printed the contents of the string, rather than the actual string literal (e.g. `the c string` instead of `c"the c string"`).
Fixes#112820
cc #105723
Use placeholders to prevent using inferred RPITIT types to imply their own well-formedness
The issue here is that we use the same signature to do RPITIT inference as we do to compute implied bounds. To fix this, when gathering the assumed wf types for the method, we replace all of the infer vars (that will be eventually used to infer RPITIT types) with type placeholders, which imply nothing about lifetime bounds.
This solution kind of sucks, but I'm not certain there's another feasible way to fix this. If anyone has a better solution, I'd be glad to hear it.
My naive first solution was, instead of using placeholders, to replace the signature with the RPITIT projections that it originally started out with. But turns out that we can't just use the unnormalized signature of the trait method in `implied_outlives_bounds` since we normalize during WF computation -- that would cause a query cycle in `collect_return_position_impl_trait_in_trait_tys`.
idk who to request review...
r? `@lcnr` or `@aliemjay` i guess.
Fixes#116060
Point at more causes of expectation of break value when possible
Follow up to #116071.
r? `@compiler-errors`
Disregard the first commit, which is in the other PR.
Don't ICE when no bound vars found while doing closure hir type check
The problem was that we were not visiting the const generic default argument in a bound where predicate when the HIR gets traversed in hir_analysis -> collect -> resolve_bound_vars.
Fixes [112574](https://github.com/rust-lang/rust/issues/112574)
Add assembly test to make sure that inlining works as expected when closures inherit target features
Closes https://github.com/rust-lang/rust/issues/108338 (the added test proves that it is working correctly)
Raise minimum supported Apple OS versions
This implements the proposal to raise the minimum supported Apple OS versions as laid out in the now-completed MCP (https://github.com/rust-lang/compiler-team/issues/556).
As of this PR, rustc and the stdlib now support these versions as the baseline:
- macOS: 10.12 Sierra
- iOS: 10
- tvOS: 10
- watchOS: 5 (Unchanged)
In addition to everything this breaks indirectly, these changes also erase the `armv7-apple-ios` target (currently tier 3) because the oldest supported iOS device now uses ARMv7s. Not sure what the policy around tier3 target removal is but shimming it is not an option due to the linker refusing.
[Per comment](https://github.com/rust-lang/compiler-team/issues/556#issuecomment-1297175073), this requires a FCP to merge. cc `@wesleywiser.`
Rollup of 5 pull requests
Successful merges:
- #116073 (Allow higher-ranked fn sigs in `ValuePairs`)
- #116082 (Tweak expected message to explain what it's actually signifying)
- #116086 (More accurate suggestion for `self.` and `Self::`)
- #116104 (Reuse calculate_debuginfo_offset for fragments.)
- #116106 (Migrate GUI colors test to original CSS color format)
r? `@ghost`
`@rustbot` modify labels: rollup
Migrate GUI colors test to original CSS color format
Follow-up of https://github.com/rust-lang/rust/pull/111459.
And with this one I'm finally done with this migration.
r? ``@notriddle``
More accurate suggestion for `self.` and `Self::`
Detect that we can't suggest `self.` in an associated function without `&self` receiver.
Partially address #115992.
r? ``@compiler-errors``
implement Literal::byte_character
without this, the only way to create a `LitKind::Byte` is by
doing `"b'a'".parse::<Literal>()`, this solves that by enabling
`Literal::byte_character(b'a')`
cc #71358
The tracking issue is #115268
without this, the only way to create a `LitKind::Byte` is by
doing `"b'a'".parse::<Literal>()`, this solves that by enabling
`Literal::byte_character(b'a')`
Enable -Zdrop-tracking-mir by default
This PR enables the `drop-tracking-mir` flag by default. This flag was initially implemented in https://github.com/rust-lang/rust/pull/101692.
This flag computes auto-traits on generators based on their analysis MIR, instead of trying to compute on the HIR body. This removes the need for HIR-based drop-tracking, as we can now reuse the same code to compute generator witness types and to compute generator interior fields.
Add codegen test to guard against VecDeque optimization regression
Very small PR that adds a codegen test to guard against regression for the `VecDeque` optimization addressed in #80836. Ensures that Rustc optimizes away the panic when unwrapping the result of `.get(0)` because of the `!is_empty()` condition.
Check that closure/generator's interior/capture types are sized
check that closure upvars and generator interiors are sized. this check is only necessary when `unsized_fn_params` or `unsized_locals` is enabled, so only check if those are active.
Fixes#93622Fixes#61335Fixes#68543
Point at cause of expectation of `break` value when possible
When encountering a type error within the value of a `break` statement, climb the HIR tree to identify if the expectation comes from an assignment or a return type (if the loop is the tail expression of a `fn`).
Fix#115905.
Rollup of 6 pull requests
Successful merges:
- #115770 (Match on elem first while building move paths)
- #115999 (Capture scrutinee of if let guards correctly)
- #116056 (Make unsized casts illegal)
- #116061 (Remove TaKO8Ki from review rotation)
- #116062 (Change `start` to `#[start]` in some diagnosis)
- #116067 (Open the FileEncoder file for reading and writing)
r? `@ghost`
`@rustbot` modify labels: rollup
Open the FileEncoder file for reading and writing
Maybe I just don't know `File` well enough, but the previous comment didn't make it clear enough to me that we can't use `File::create`. This one does.
Fixes https://github.com/rust-lang/rust/issues/116055
r? `@WaffleLapkin`
[breaking change] Validate crate name in `--extern` [MCP 650]
Reject non-ASCII-identifier crate names passed to the CLI option `--extern` (`rustc`, `rustdoc`).
Implements [MCP 650](https://github.com/rust-lang/compiler-team/issues/650) (except that we only allow ASCII identifiers not arbitrary Rust identifiers).
Fixes#113035.
[As mentioned on Zulip](https://rust-lang.zulipchat.com/#narrow/stream/233931-t-compiler.2Fmajor-changes/topic/Disallow.20non-identifier-valid.20--extern.20cr.E2.80.A6.20compiler-team.23650/near/376826988), doing a crater run probably doesn't make sense since it wouldn't yield anything. Most users don't interact with `rustc` directly but only ever through Cargo which always passes a valid crate name to `--extern` when it invokes `rustc` and `rustdoc`. In any case, the user wouldn't be able to use such a crate name in the source code anyway.
Note that I'm not using [`rustc_session::output::validate_crate_name`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_session/output/fn.validate_crate_name.html) (used for `--crate-name` and `#![crate_name]`) since the latter doesn't reject non-ASCII crate names and ones that start with a digit.
As an aside, I've also thought about getting rid of `validate_crate_name` entirely in a separate PR (with another MCP) in favor of `is_ascii_ident` to reject more weird `--crate-name`s, `#![crate_name]`s and file names but I think that would lead to a lot of actual breakage, namely because of file names starting with a digit. In `tests/ui` 9 tests would be impacted for example.
CC `@estebank`
r? `@est31`
adjust how closure/generator types are printed
I saw `&[closure@$DIR/issue-20862.rs:2:5]` and I thought it is a slice type, because that's usually what `&[_]` is... it took me a while to realize that this is just a confusing printer and actually there's no slice. Let's use something that cannot be mistaken for a regular type.
give FutureIncompatibilityReason variants more explicit names
Also make the `reason` field mandatory when declaring a lint, to make sure this is a deliberate decision.
tests/ui: Split large_moves.rs and move to lint/large_assignments
To make failing tests easier to debug with `--emit=mir`, etc.
Don't bother with `revisions: attribute option` for both tests though. Seems sufficient to just have that on one of the tests.
`git show -M --find-renames=40%` makes the diff easier to review. Or note that before this change we had one test with 4 errors, now we have 2 tests with 2 errors each.
r? `@oli-obk`
Part of https://github.com/rust-lang/rust/issues/83518
This happens because variances are constructed from ty generics,
and ty generics are always constructed with lifetimes first.
See compiler/rustc_hir_analysis/src/collect/generics_of.rs:248-269
Fixes#83556
rustc_hir_analysis: add a helper to check function the signature mismatches
This function is now used to check `#[panic_handler]`, `start` lang item, `main`, `#[start]` and intrinsic functions.
The diagnosis produced are now closer to the ones produced by trait/impl method signature mismatch.
This is the first time I do anything with rustc_hir_analysis/rustc_hir_typeck, so comments and suggestions about things I did wrong or that could be improved will be appreciated.
This whole thing changes it so that the JS and the UI both use
rustc's own path printing to handle the impl IDs. This results in
the format changing a little bit; full paths are used in spots
where they aren't strictly necessary, and the path sometimes uses
generics where the old system used the trait's own name, but it
shouldn't matter since the orphan rules will prevent it anyway.
Helps with #90929
This changes the search results, specifically, when there's more than
one impl with an associated item with the same name. For example,
the search queries `simd<i8> -> simd<i8>` and `simd<i64> -> simd<i64>`
don't link to the same function, but most of the functions have the
same names.
This change should probably be FCP-ed, especially since it adds a new
anchor link format for `main.js` to handle, so that URLs like
`struct.Vec.html#impl-AsMut<[T]>-for-Vec<T,+A>/method.as_mut` redirect
to `struct.Vec.html#method.as_mut-2`. It's a strange design, but there
are a few reasons for it:
* I'd like to avoid making the HTML bigger. Obviously, fixing this bug
is going to add at least a little more data to the search index, but
adding more HTML penalises viewers for the benefit of searchers.
* Breaking `struct.Vec.html#method.len` would also be a disappointment.
On the other hand:
* The path-style anchors might be less prone to link rot than the numbered
anchors. It's definitely less likely to have URLs that appear to "work",
but silently point at the wrong thing.
* This commit arranges the path-style anchor to redirect to the numbered
anchor. Nothing stops rustdoc from doing the opposite, making path-style
anchors the default and redirecting the "legacy" numbered ones.
Suggest desugaring to return-position `impl Future` when an `async fn` in trait fails an auto trait bound
First commit allows us to store the span of the `async` keyword in HIR.
Second commit implements a suggestion to desugar an `async fn` to a return-position `impl Future` in trait to slightly improve the `Send` situation being discussed in #115822.
This suggestion is only made when `#![feature(return_type_notation)]` is not enabled -- if it is, we should instead suggest an appropriate where-clause bound.
coverage: Don't bother renumbering expressions on the Rust side
The LLVM API that we use to encode coverage mappings already has its own code for removing unused coverage expressions and renumbering the rest.
This lets us get rid of our own complex renumbering code, making it easier to change our coverage code in other ways.
---
Now that we have tests for coverage mappings (#114843), I've been able to verify that this PR doesn't make the coverage mappings worse, thanks to an explicit simplification step.
Delete obsolete `--disable-per-crate-search` rustdoc flag
This unstable flag is unused by rustdoc since ef96d573bf.
We should avoid landing this until after https://github.com/rust-lang/docs.rs/pull/2225 is deployed to docs.rs.
rename mir::Constant -> mir::ConstOperand, mir::ConstKind -> mir::Const
Also, be more consistent with the `to/eval_bits` methods... we had some that take a type and some that take a size, and then sometimes the one that takes a type is called `bits_for_ty`.
Turns out that `ty::Const`/`mir::ConstKind` carry their type with them, so we don't need to even pass the type to those `eval_bits` functions at all.
However this is not properly consistent yet: in `ty` we have most of the methods on `ty::Const`, but in `mir` we have them on `mir::ConstKind`. And indeed those two types are the ones that correspond to each other. So `mir::ConstantKind` should actually be renamed to `mir::Const`. But what to do with `mir::Constant`? It carries around a span, that's really more like a constant operand that appears as a MIR operand... it's more suited for `syntax.rs` than `consts.rs`, but the bigger question is, which name should it get if we want to align the `mir` and `ty` types? `ConstOperand`? `ConstOp`? `Literal`? It's not a literal but it has a field called `literal` so it would at least be consistently wrong-ish...
``@oli-obk`` any ideas?
Prevent promotion of const fn calls in inline consts
We don't wanna make that mistake we did for statics and consts worse by letting more code use it.
r? ``@RalfJung``
cc https://github.com/rust-lang/rust/issues/76001
Improve invalid UTF-8 lint by finding the expression initializer
This PR introduce a small mechanism to walk up the HIR through bindings, if/else, consts, ... when trying lint on invalid UTF-8.
Fixes https://github.com/rust-lang/rust/issues/115208
After coverage instrumentation and MIR transformations, we can sometimes end up
with coverage expressions that always have a value of zero. Any expression
operand that refers to an always-zero expression can be replaced with a literal
`Operand::Zero`, making the emitted coverage mapping data smaller and simpler.
This simplification step is mostly redundant with the simplifications performed
inline in `expressions_with_regions`, except that it does a slightly more
thorough job in some cases (because it checks for always-zero expressions
*after* other simplifications).
However, adding this simplification step will then let us greatly simplify that
code, without affecting the quality of the emitted coverage maps.
rustc_target/loongarch: Fix passing of transparent unions with only one non-ZST member
This ensures that `MaybeUninit<T>` has the same ABI as `T` when passed through an `extern "C"` function.
Fixes https://github.com/rust-lang/rust/issues/115509
r? `@bjorn3`
coverage: Remove debug code from the instrumentor
The coverage instrumentor has an entire module full of complex code that is only used for debugging.
And as I continue to work on coverage, I keep finding that this debug code is constantly causing more trouble than it's worth. It's deeply entangled with current implementation details, such that making any non-trivial change to the instrumentor usually requires major changes to the debug code. And so far I have personally not found any of this debug code to be *useful*.
In light of that situation, I'd like to try just ripping all of it out. If I spend any more time dealing with coverage debug code, I want it to be because I'm writing new and useful tools, not dutifully maintaining a boat-anchor that quite plausibly isn't being used by anyone at all.
---
r? `@ghost`
`@rustbot` label +A-code-coverage
---
[Zulip thread](https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/Removing.20debug.20code.20from.20the.20coverage.20instrumentor)
Correctly deny late-bound lifetimes from parent in anon consts and TAITs
Reuse the `AnonConstBoundary` scope (introduced in #108553, renamed in this PR to `LateBoundary`) to deny late-bound vars of *all* kinds (ty/const/lifetime) in anon consts and TAITs.
Side-note, but I would like to consolidate this with the error reporting for RPITs (E0657):
c4f25777a0/compiler/rustc_hir_analysis/src/collect/resolve_bound_vars.rs (L733-L754) but the semantics about what we're allowed to capture there are slightly different, so I'm leaving that untouched.
Fixes#115474
Custom code classes in docs warning
Fixes https://github.com/rust-lang/rust/issues/115938.
This PR does two things:
1. Unless the `custom_code_classes_in_docs` feature is enabled, it will use the old codeblock tag parser.
2. If there is a codeblock tag that starts with a `.`, it will emit a behaviour change warning.
Hopefully this is the last missing part for this feature until stabilization.
Follow-up of https://github.com/rust-lang/rust/pull/110800.
r? `@notriddle`
Detect cycle errors hidden by opaques during monomorphization
Opaque types may reveal to projections, which themselves normalize to opaques. We don't currently normalize when checking that opaques are cyclical, and we may also not know that the opaque is cyclical until monomorphization (see `tests/ui/type-alias-impl-trait/mututally-recursive-overflow.rs`).
Detect cycle errors in `normalize_projection_ty` and report a fatal overflow (in the old solver). Luckily, this is already detected as a fatal overflow in the new solver.
Fixes#112047
rustc_target/riscv: Fix passing of transparent unions with only one non-ZST member
This ensures that `MaybeUninit<T>` has the same ABI as `T` when passed through an `extern "C"` function.
Fixes https://github.com/rust-lang/rust/issues/115481.
r? `@RalfJung`
Don't modify libstd to dump rustc ICEs
Do a much simpler thing and just dump a `std::backtrace::Backtrace` to file.
r? `@estebank` `@oli-obk`
Fixes#115610
This function is now used to check `#[panic_handler]`, `start` lang item, `main`, `#[start]` and intrinsic functions.
The diagnosis produced are now closer to the ones produced by trait/impl method signature mismatch.
move things out of mir/mod.rs
This moves a bunch of things out of `mir/mod.rs`:
- all const-related stuff to a new file consts.rs
- all statement/place/operand-related stuff to a new file statement.rs
- all pretty-printing related stuff to pretty.rs
`mod.rs` started out with 3100 lines and ends up with 1600. :)
Also there was some pretty-printing stuff in terminator.rs, that also got moved to pretty.rs, and I reordered things in pretty.rs so that it can be grouped by functionality.
Only the commit "use pretty_print_const_value from MIR constant 'extra' printing" has any behavior changes; it resolves the issue of having a fancy and a very crude pretty-printer for `ConstValue`.
r? `@oli-obk`
Don't complain on a single non-exhaustive 1-ZST
r? RalfJung, though you mentioned being busy, so feel free to reassign.
This doesn't actually attempt to make the diagnostic better, so when we have two non-exhaustive 1-ZSTs in a struct, we still just point to one. 🤷Fixes#115922
Explain HRTB + infer limitations of old solver
Add a helpful message when we hit the limitation of the old trait solver where we don't properly normalize GATs with infer vars + bound vars, leading to too-eagerly reporting trait errors that would be later satisfied due to inference.
Don't resolve generic impls that may be shadowed by dyn built-in impls
**NOTE:** This is a hack. This is not trying to be a general fix for the issue that we've allowed overlapping built-in trait object impls and user-written impls for quite a long time, and traits like `Any` rely on this (#57893) -- this PR specifically aims to mitigate a new unsoundness that is uncovered by the MIR inliner (#114928) that interacts with this pre-existing issue.
Builtin `dyn Trait` impls may overlap with user-provided blanket impls (`impl<T: ?Sized> Trait for T`) in generic contexts. This leads to bugs when instances are resolved in polymorphic contexts, since we typically prefer object candidates over impl candidates.
This PR implements a (hacky) heuristic to `resolve_associated_item` to account for that unfortunate hole in the type system -- we now bail with ambiguity if we try to resolve a non-rigid instance whose self type is not known to be sized. This makes sure we can still inline instances like `impl<T: Sized> Trait for T`, which can never overlap with `dyn Trait`'s built-in impl, but we avoid inlining an impl that may be shadowed by a `dyn Trait`.
Fixes#114928
rustdoc-search: add support for type parameters
r? `@GuillaumeGomez`
## Preview
* https://notriddle.com/rustdoc-html-demo-4/advanced-search/rustdoc/read-documentation/search.html
* https://notriddle.com/rustdoc-html-demo-4/advanced-search/std/index.html?search=option%3Coption%3CT%3E%3E%20-%3E%20option%3CT%3E
* https://notriddle.com/rustdoc-html-demo-4/advanced-search/std/index.html?search=option%3CT%3E,%20E%20-%3E%20result%3CT,%20E%3E
* https://notriddle.com/rustdoc-html-demo-4/advanced-search/std/index.html?search=-%3E%20option%3CT%3E
## Description
When writing a type-driven search query in rustdoc, specifically one with more than one query element, non-existent types become generic parameters instead of auto-correcting (which is currently only done for single-element queries) or giving no result. You can also force a generic type parameter by writing `generic:T` (and can force it to not use a generic type parameter with something like `struct:T` or whatever, though if this happens it means the thing you're looking for doesn't exist and will give you no results).
There is no syntax provided for specifying type constraints for generic type parameters.
When you have a generic type parameter in a search query, it will only match up with generic type parameters in the actual function, not concrete types that match, not concrete types that implement a trait. It also strictly matches based on when they're the same or different, so `option<T>, option<U> -> option<U>` matches `Option::and`, but not `Option::or`. Similarly, `option<T>, option<T> -> option<T>` matches `Option::or`, but not `Option::and`.
## Motivation
This feature is motivated by the many "combinitor"-type functions found in generic libraries, such as Option, Future, Iterator, and Entry. These highly-generic functions have names that are almost completely arbitrary, and a type signature that tells you what it actually does.
This PR is a major step towards[^closure] being able to easily search for generic functions by their type signature instead of by name. Some examples of combinators that can be found using this PR (try them out in the preview):
* `option<option<T>> -> option<T>` returns Option::flatten
* `option<T> -> result<T>` returns Option::ok_or
* `option<result<T>> -> result<option<T>>` returns Option::transpose
* `entry<K, V>, FnOnce -> V` returns `Entry::or_insert_with` (and `or_insert_with_key`, since there's no way to specify the generics on FnOnce)
[^closure]:
For this feature to be as useful as it ought to be, you should be able to search for *trait-associated types* and *closures*. This PR does not implement either of these: they are **Future possibilities**.
Trait-associated types would allow queries like `option<T> -> iterator<item=T>` to return `Option::iter`. We should also allow `option<T> -> iterator<T>` to match the associated type version.
Closures would make a good way to query for things like `Option::map`. Closure support needs associated types to be represented in the search index, since `FnOnce() -> i32` desugars to `FnOnce<Output=i32, ()>`, so associated trait types should be implemented first. Also, we'd want to expose an easy way to query closures without specifying which of the three traits you want.
coverage: Fix an unstable-sort inconsistency in coverage spans
This code was calling `sort_unstable_by`, but failed to impose a total order on the initial spans. That resulted in unpredictable handling of closure spans, producing inconsistencies in the coverage maps and in user-visible coverage reports.
This PR fixes the problem by always sorting closure spans before otherwise-identical non-closure spans, and also switches to a stable sort in case the ordering is still not total.
---
In addition to the fix itself, this PR also contains a cleanup to the comparison function that I was working on when I discovered the bug.
Make `TyKind::Adt`'s `Debug` impl be more pretty
Currently `{:?}` on `Ty` for a `TyKind::Adt` would print as `Adt(Foo, [])`. This PR changes it to be `Foo` when there are no generics or `Foo<T>`/`Foo<T, U>` when there _are_ generics. Example from debug log:
`├─0ms DEBUG rustc_hir_analysis::astconv return=Bar<T/#0, U/#1>`
I should have done this in my initial PR for a prettier TyKind: Debug impl but I thought I would need to be accessing generics_of to figure out where in the "path" the generics would have to go??? but no, adts literally only have a single place the generics can go (on the end). Feel a bit silly about this :)
r? `@oli-obk`
Avoid blessing cargo deps's source code in ui tests
Before this PR, the source code of dependencies was included in UI test error messages whenever possible. Unfortunately, "whenever possible" means in some cases the source code wouldn't be injected, resulting in a test failure.
One such case is when `$CARGO_HOME` is remapped to something that is not present on disk [^1]. As the remapped path doesn't exist on disk, the source code wouldn't be showed in `tests/ui/issues/issue-21763.rs`:
```diff
= note: required for `hashbrown::raw::RawTable<(Rc<()>, Rc<()>)>` to implement `Send`
note: required because it appears within the type `HashMap<Rc<()>, Rc<()>, RandomState>`
--> $HASHBROWN_SRC_LOCATION
- |
-LL | pub struct HashMap<K, V, S = DefaultHashBuilder, A: Allocator + Clone = Global> {
- | ^^^^^^^
note: required because it appears within the type `HashMap<Rc<()>, Rc<()>>`
--> $SRC_DIR/std/src/collections/hash/map.rs:LL:COL
note: required by a bound in `foo`
```
This PR fixes the problem by always hiding dependencies source code in the error messages generated during UI tests. This is implemented with a new internal flag, `-Z ignore-directory-in-diagnostics-source-blocks=$path`, which compiletest passes during UI tests. Once this is merged, remapping the Cargo home will be supported.
This PR is best reviewed commit-by-commit.
[^1]: After being puzzled for a bit, I discovered why this never impacted `rust-lang/rust`: we don't remap `$CARGO_HOME` 😅. Instead, we set `$CARGO_HOME` to `/cargo` in CI, which sort-of-but-not-really achieves the same effect.
move required_consts check to general post-mono-check function
This factors some code that is common between the interpreter and the codegen backends into shared helper functions. Also as a side-effect the interpreter now uses the same `eval` functions as everyone else to get the evaluated MIR constants.
Also this is in preparation for another post-mono check that will be needed for (the current hackfix for) https://github.com/rust-lang/rust/issues/115709: ensuring that all locals are dynamically sized.
I didn't expect this to change diagnostics, but it's just cycle errors that change.
r? `@oli-obk`
This code was calling `sort_unstable_by`, but failed to impose a total order on
the initial spans. That resulted in unpredictable handling of closure spans,
producing inconsistencies in the coverage maps and in user-visible coverage
reports.
This patch fixes the problem by always sorting closure spans before
otherwise-identical non-closure spans, and also switches to a stable sort in
case the ordering is still not total.
Turn custom code classes in docs into warning
By habit, since it was a new feature gate, I added a check which emitted an error in case the new syntax was used. However, since rustdoc tags parser was accepting *everything*, using the "new" syntax should never ever emit errors. It now emits a warning.
Follow-up of #110800.
cc `@Manishearth`
r? `@notriddle`
repr(transparent): it's fine if the one non-1-ZST field is a ZST
This code currently gets rejected:
```rust
#[repr(transparent)]
struct MyType([u16; 0])
```
That clearly seems like a bug to me: `repr(transparent)` [got defined ](https://github.com/rust-lang/rust/issues/77841#issuecomment-716575747) as having any number of 1-ZST fields plus optionally one more field; `MyType` clearly satisfies that definition.
This PR changes the `repr(transparent)` logic to actually match that definition.
Rollup of 6 pull requests
Successful merges:
- #114965 (Remove Drop impl of mpsc Receiver and (Sync)Sender)
- #115434 (make `Debug` impl for `ascii::Char` match that of `char`)
- #115477 (Stabilize the `Saturating` type)
- #115611 (add diagnostic for raw identifiers in format string)
- #115654 (improve PassMode docs)
- #115862 (Migrate `compiler/rustc_hir_typeck/src/callee.rs` to translatable diagnostics)
r? `@ghost`
`@rustbot` modify labels: rollup
Make `.rmeta` file in `dep-info` have correct name (`lib` prefix)
Since `filename_for_metadata()` and
`OutputFilenames::path(OutputType::Metadata)` had different logic for the name of the metadata file, the `.d` file contained a file name different from the actual name used. Share the logic to fix the out-of-sync name.
Without this fix, the `.d` file contained
dash-separated_something-extra.rmeta: dash-separated.rs
instead of
libdash_separated_something-extra.rmeta: dash-separated.rs
which is the name of the file that is actually written by the compiler.
Worth noting: It took me several iterations to get all tests to pass, so I am relatively confident that this PR does not break anything.
Closes#68839
add diagnostic for raw identifiers in format string
Format strings don't support raw identifiers (e.g. `format!("{r#type}")`), but they do support keywords in the format string directly (e.g. `format!("{type}")`). This PR improves the error output when attempting to use a raw identifier in a format string and adds a machine-applicable suggestion to remove the `r#`.
fixes https://github.com/rust-lang/rust/issues/115466
`#[diagnostic::on_unimplemented]` without filters
This commit adds support for a `#[diagnostic::on_unimplemented]` attribute with the following options:
* `message` to customize the primary error message
* `note` to add a customized note message to an error message
* `label` to customize the label part of the error message
The relevant behavior is specified in [RFC-3366](https://rust-lang.github.io/rfcs/3366-diagnostic-attribute-namespace.html)
impl Step for IP addresses
ACP: rust-lang/libs-team#235
Note: since this is insta-stable, it requires an FCP.
Separating out from the bit operations PR since it feels logically disjoint, and so their FCPs can be separate.
Accept additional user-defined syntax classes in fenced code blocks
Part of #79483.
This is a re-opening of https://github.com/rust-lang/rust/pull/79454 after a big update/cleanup. I also converted the syntax to pandoc as suggested by `@notriddle:` the idea is to be as compatible as possible with the existing instead of having our own syntax.
## Motivation
From the original issue: https://github.com/rust-lang/rust/issues/78917
> The technique used by `inline-c-rs` can be ported to other languages. It's just super fun to see C code inside Rust documentation that is also tested by `cargo doc`. I'm sure this technique can be used by other languages in the future.
Having custom CSS classes for syntax highlighting will allow tools like `highlight.js` to be used in order to provide highlighting for languages other than Rust while not increasing technical burden on rustdoc.
## What is the feature about?
In short, this PR changes two things, both related to codeblocks in doc comments in Rust documentation:
* Allow to disable generation of `language-*` CSS classes with the `custom` attribute.
* Add your own CSS classes to a code block so that you can use other tools to highlight them.
#### The `custom` attribute
Let's start with the new `custom` attribute: it will disable the generation of the `language-*` CSS class on the generated HTML code block. For example:
```rust
/// ```custom,c
/// int main(void) {
/// return 0;
/// }
/// ```
```
The generated HTML code block will not have `class="language-c"` because the `custom` attribute has been set. The `custom` attribute becomes especially useful with the other thing added by this feature: adding your own CSS classes.
#### Adding your own CSS classes
The second part of this feature is to allow users to add CSS classes themselves so that they can then add a JS library which will do it (like `highlight.js` or `prism.js`), allowing to support highlighting for other languages than Rust without increasing burden on rustdoc. To disable the automatic `language-*` CSS class generation, you need to use the `custom` attribute as well.
This allow users to write the following:
```rust
/// Some code block with `{class=language-c}` as the language string.
///
/// ```custom,{class=language-c}
/// int main(void) {
/// return 0;
/// }
/// ```
fn main() {}
```
This will notably produce the following HTML:
```html
<pre class="language-c">
int main(void) {
return 0;
}</pre>
```
Instead of:
```html
<pre class="rust rust-example-rendered">
<span class="ident">int</span> <span class="ident">main</span>(<span class="ident">void</span>) {
<span class="kw">return</span> <span class="number">0</span>;
}
</pre>
```
To be noted, we could have written `{.language-c}` to achieve the same result. `.` and `class=` have the same effect.
One last syntax point: content between parens (`(like this)`) is now considered as comment and is not taken into account at all.
In addition to this, I added an `unknown` field into `LangString` (the parsed code block "attribute") because of cases like this:
```rust
/// ```custom,class:language-c
/// main;
/// ```
pub fn foo() {}
```
Without this `unknown` field, it would generate in the DOM: `<pre class="language-class:language-c language-c">`, which is quite bad. So instead, it now stores all unknown tags into the `unknown` field and use the first one as "language". So in this case, since there is no unknown tag, it'll simply generate `<pre class="language-c">`. I added tests to cover this.
Finally, I added a parser for the codeblock attributes to make it much easier to maintain. It'll be pretty easy to extend.
As to why this syntax for adding attributes was picked: it's [Pandoc's syntax](https://pandoc.org/MANUAL.html#extension-fenced_code_attributes). Even if it seems clunkier in some cases, it's extensible, and most third-party Markdown renderers are smart enough to ignore Pandoc's brace-delimited attributes (from [this comment](https://github.com/rust-lang/rust/pull/110800#issuecomment-1522044456)).
## Raised concerns
#### It's not obvious when the `language-*` attribute generation will be added or not.
It is added by default. If you want to disable it, you will need to use the `custom` attribute.
#### Why not using HTML in markdown directly then?
Code examples in most languages are likely to contain `<`, `>`, `&` and `"` characters. These characters [require escaping](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/pre) when written inside the `<pre>` element. Using the \`\`\` code blocks allows rustdoc to take care of escaping, which means doc authors can paste code samples directly without manually converting them to HTML.
cc `@poliorcetics`
r? `@notriddle`
closure field capturing: don't depend on alignment of packed fields
This fixes the closure field capture part of https://github.com/rust-lang/rust/issues/115305: field capturing always stops at projections into packed structs, no matter the alignment of the field. This means changing a private field type from `u8` to `u64` can never change how closures capture fields, which is probably what we want.
Here's an example where, before this PR, changing the type of a private field in a repr(Rust) struct can change the output of a program:
```rust
#![allow(dead_code)]
mod m {
// before patch
#[derive(Default)]
pub struct S1(u8);
// after patch
#[derive(Default)]
pub struct S2(u64);
}
struct NoisyDrop;
impl Drop for NoisyDrop {
fn drop(&mut self) {
eprintln!("dropped!");
}
}
#[repr(packed)]
struct MyType {
field: m::S1, // output changes when this becomes S2
other_field: NoisyDrop,
third_field: Vec<()>,
}
fn test(r: MyType) {
let c = || {
let _val = std::ptr::addr_of!(r.field);
let _val = r.third_field;
};
drop(c);
eprintln!("before dropping");
}
fn main() {
test(MyType {
field: Default::default(),
other_field: NoisyDrop,
third_field: Vec::new(),
});
}
```
Of course this is a breaking change for the same reason that doing field capturing in the first place was a breaking change. Packed fields are relatively rare and depending on drop order is relatively rare, so I don't expect this to have much impact, but it's hard to be sure and even a crater run will only tell us so much.
Also see the [nomination comment](https://github.com/rust-lang/rust/pull/115315#issuecomment-1702807825).
Cc `@rust-lang/wg-rfc-2229` `@ehuss`
Make useless_ptr_null_checks smarter about some std functions
This teaches the `useless_ptr_null_checks` lint that some std functions can't ever return null pointers, because they need to point to valid data, get references as input, etc.
This is achieved by introducing an `#[rustc_never_returns_null_ptr]` attribute and adding it to these std functions (gated behind bootstrap `cfg_attr`).
Later on, the attribute could maybe be used to tell LLVM that the returned pointer is never null. I don't expect much impact of that though, as the functions are pretty shallow and usually the input data is already never null.
Follow-up of PR #113657Fixes#114442
