Currently we always do this:
```
use rustc_fluent_macro::fluent_messages;
...
fluent_messages! { "./example.ftl" }
```
But there is no need, we can just do this everywhere:
```
rustc_fluent_macro::fluent_messages! { "./example.ftl" }
```
which is shorter.
The `fluent_messages!` macro produces uses of
`crate::{D,Subd}iagnosticMessage`, which means that every crate using
the macro must have this import:
```
use rustc_errors::{DiagnosticMessage, SubdiagnosticMessage};
```
This commit changes the macro to instead use
`rustc_errors::{D,Subd}iagnosticMessage`, which avoids the need for the
imports.
Remove `HirId` from `QPath::LangItem`
Remove `HirId` from `QPath::LangItem`, since there was only *one* use-case (`ObligationCauseCode::AwaitableExpr`), which we can instead recover by walking the HIR tree.
Optimize QueryArena allocation
This shifts the WorkerLocal wrapper to be outside the QueryArena, meaning that instead of having each query allocate distinct arenas per-worker we allocate the full set of arenas per-worker. This is primarily a code size optimization (locally, ~85 kilobytes, [perf is reporting >100 kilobytes](https://perf.rust-lang.org/compare.html?start=1fd418f92ed13db88a21865ba5d909abcf16b6cc&end=884c95a3f1fe8d28630ec3cdb0c8f95b2e539fde&stat=instructions%3Au&tab=artifact-size)), saving a bunch of code in the initialization of the arenas which was previously duplicated lots of times (per arena type).
Additionally this tells LLVM that the thread count can't be zero in this code (I believe this is true?) which shaves some small amount of bytes off as well since we eliminate checks for zero in the vec allocations.
Cache flags for `ty::Const`
Not sure if this has been attempted yet, but worth a shot. It does make the code simpler in `rustc_type_ir`, since we can assume that consts have a `flags` method that is no-cost.
r? `@ghost`
Remove `PredicateKind::ClosureKind`
We don't need the `ClosureKind` predicate kind -- instead, `Fn`-family trait goals are left as ambiguous, and we only need to make progress on `FnOnce` projection goals for inference purposes.
This is similar to how we do confirmation of `Fn`-family trait and projection goals in the new trait solver, which also doesn't use the `ClosureKind` predicate.
Some hacky logic is added in the second commit so that we can keep the error messages the same.
Rollup of 6 pull requests
Successful merges:
- #118012 (Add support for global allocation in smir)
- #118013 (Enable Rust to use the EHCont security feature of Windows)
- #118100 (Enable profiler in dist-powerpc64-linux)
- #118142 (Tighten up link attributes for llvm-wrapper bindings)
- #118147 (Fix some unnecessary casts)
- #118161 (Allow defining opaques in `check_coroutine_obligations`)
r? `@ghost`
`@rustbot` modify labels: rollup
Allow defining opaques in `check_coroutine_obligations`
In the new trait solver, when an obligation stalls on an unresolved coroutine witness, we will stash away the *root* obligation, even if the stalled obligation is only a distant descendent of the root obligation, since the new solver is purely recursive.
This means that we may need to reprocess alias-relate obligations (and others) which may define opaque types in the new solver. Currently, we use the coroutine's def id as the defining anchor in `check_coroutine_obligations`, which will allow defining no opaque types, resulting in errors like:
```
error[E0271]: type mismatch resolving `{coroutine@<source>:6:5: 6:17} <: impl Clone`
--> <source>:6:5
|
6 | / move |_: ()| {
7 | | let () = yield ();
8 | | }
| |_____^ types differ
```
So this PR fixes the defining anchor and does the same trick as `check_opaque_well_formed`, where we manually compare opaques that were defined against their hidden types to make sure they weren't defined differently when processing these stalled coroutine obligations.
r? `@lcnr` cc `@cjgillot`
By default, `newtype_index!` types get a default `Encodable`/`Decodable`
impl. You can opt out of this with `custom_encodable`. Opting out is the
opposite to how Rust normally works with autogenerated (derived) impls.
This commit inverts the behaviour, replacing `custom_encodable` with
`encodable` which opts into the default `Encodable`/`Decodable` impl.
Only 23 of the 59 `newtype_index!` occurrences need `encodable`.
Even better, there were eight crates with a dependency on
`rustc_serialize` just from unused default `Encodable`/`Decodable`
impls. This commit removes that dependency from those eight crates.
Uplift `CanonicalVarInfo` and friends into `rustc_type_ir`
Depends on #117580 and #117578
Uplift `CanonicalVarInfo` and friends into `rustc_type_ir` so they can be consumed by an interner-agnostic `Canonicalizer` implementation for the new trait solver ❤️
r? `@ghost`
Rollup of 5 pull requests
Successful merges:
- #117972 (Add VarDebugInfo to Stable MIR)
- #118109 (rustdoc-search: simplify `checkPath` and `sortResults`)
- #118110 (Document `DefiningAnchor` a bit more)
- #118112 (Don't ICE when ambiguity is found when selecting `Index` implementation in typeck)
- #118135 (Remove quotation from filename in stable_mir)
Failed merges:
- #118012 (Add support for global allocation in smir)
r? `@ghost`
`@rustbot` modify labels: rollup
Expand Miri's BorTag GC to a Provenance GC
As suggested in https://github.com/rust-lang/miri/issues/3080#issuecomment-1732505573
We previously solved memory growth issues associated with the Stacked Borrows and Tree Borrows runtimes with a GC. But of course we also have state accumulation associated with whole allocations elsewhere in the interpreter, and this PR starts tackling those.
To do this, we expand the visitor for the GC so that it can visit a BorTag or an AllocId. Instead of collecting all live AllocIds into a single HashSet, we just collect from the Machine itself then go through an accessor `InterpCx::is_alloc_live` which checks a number of allocation data structures in the core interpreter. This avoids the overhead of all the inserts that collecting their keys would require.
r? ``@RalfJung``
Rollup of 8 pull requests
Successful merges:
- #117327 (Add documentation for some queries)
- #117835 (Note about object lifetime defaults in does not live long enough error)
- #117851 (Uplift `InferConst` to `rustc_type_ir`)
- #117973 (test: Add test for async-move in 2015 Rust proc macro)
- #117992 (Don't require intercrate mode for negative coherence)
- #118010 (Typeck break expr even if break is illegal)
- #118026 (Don't consider regions in `deref_into_dyn_supertrait` lint)
- #118089 (intercrate_ambiguity_causes: handle self ty infer + reservation impls)
r? `@ghost`
`@rustbot` modify labels: rollup
Uplift `InferConst` to `rustc_type_ir`
We need this in `rustc_type_ir` because the canonicalizer must understand the difference between a const vid and an effect vid. In that way, it's not an implementation detail of the representation of an infer const, but just part of the type ir.
If we find out later on that it's better to leave the representation up to the consumer of `rustc_type_ir`, we could abstract `InferConst` (and probably `InferTy` as well) with some traits, but I don't see the benefit of that indirection currently.
Note about object lifetime defaults in does not live long enough error
This is a aspect of Rust that frequently trips up people who are not aware of it yet. This diagnostic attempts to explain what's happening and why the lifetime constraint, that was never mentioned in the source, arose.
The implementation feels a bit questionable, I'm not sure whether there are better ways to do this. There probably are.
fixes#117835
r? types
interpret: simplify handling of shifts by no longer trying to handle signed and unsigned shift amounts in the same branch
While we're at it, also update comments in codegen and MIR building related to shifts, and fix the overflow error printed by Miri on negative shift amounts.
new solver normalization improvements
cool beans
At the core of this PR is a `try_normalize_ty` which stops for rigid aliases by using `commit_if_ok`.
Reworks alias-relate to fully normalize both the lhs and rhs and then equate the resulting rigid (or inference) types. This fixes https://github.com/rust-lang/trait-system-refactor-initiative/issues/68 by avoiding the exponential blowup. Also supersedes #116369 by only defining opaque types if the hidden type is rigid.
I removed the stability check in `EvalCtxt::evaluate_goal` due to https://github.com/rust-lang/trait-system-refactor-initiative/issues/75. While I personally have opinions on how to fix it, that still requires further t-types/`@nikomatsakis` buy-in, so I removed that for now. Once we've decided on our approach there, we can revert this commit.
r? `@compiler-errors`
This was made possible by the removal of plugin support, which
simplified lint store creation.
This simplifies the places in rustc and rustdoc that call
`describe_lints`, which are early on. The lint store is now built before
those places, so they don't have to create their own lint store for
temporary use, they can just use the main one.
finish `RegionKind` renaming
second step of https://github.com/rust-lang/types-team/issues/95
continues the work from #117876. While working on this and I encountered a bunch of further cleanup which I'll either open a tracking issue for or will do in a separate PR:
- rewrite the `RegionKind` docs, they still talk about `ReEmpty` and are generally out of date
- rename `DescriptionCtx` to `DescriptionCtxt`
- what is `CheckRegions::Bound`?
- `collect_late_bound_regions` et al
- `erase_late_bound_regions` -> `instantiate_bound_regions_with_erased`?
- `EraseEarlyRegions` visitor should be removed, feels duplicate
r? `@BoxyUwU`
make `LayoutError::Cycle` carry `ErrorGuaranteed`
Addresses a FIXME, and also I think it's wise for error variants to carry their `ErrorGuaranteed` -- makes it easier to use that `ErrorGuaranteed` for creating, e.g. `TyKind::Error` and other error kinds. Splitting out from #117703.
Rollup of 4 pull requests
Successful merges:
- #114224 (rustc_llvm: Link to libkstat on Solaris/SPARC)
- #117695 (Reorder checks to make sure potential missing expect on Option/Result…)
- #117870 (`fn args_ref_X` to `fn args_X`)
- #117879 (tests: update check for inferred nneg on zext)
r? `@ghost`
`@rustbot` modify labels: rollup
This is a aspect of Rust that frequently trips up people who are not
aware of it yet. This diagnostic attempts to explain what's happening
and why the lifetime constraint, that was never mentioned in the source,
arose.
Add `std:#️⃣:{DefaultHasher, RandomState}` exports (needs FCP)
This implements rust-lang/libs-team#267 to move the libstd hasher types to `std::hash` where they belong, instead of `std::collections::hash_map`.
<details><summary>The below no longer applies, but is kept for clarity.</summary>
This is a small refactor for #27242, which moves the definitions of `RandomState` and `DefaultHasher` into `std::hash`, but in a way that won't be noticed in the public API.
I've opened rust-lang/libs-team#267 as a formal ACP to move these directly into the root of `std::hash`, but for now, they're at least separated out from the collections code in a way that will make moving that around easier.
I decided to simply copy the rustdoc for `std::hash` from `core::hash` since I think it would be ideal for the two to diverge longer-term, especially if the ACP is accepted. However, I would be willing to factor them out into a common markdown document if that's preferred.
</details>
Fix some clippy perf lints
`@matthiaskrgr` gave me the output of a clippy run with perf lints enabled. This PR fixes ones that I thought were worth fixing.
r? `@cuviper`
Thir unsafeck fixes
- Recognise thread local statics in THIR unsafeck
- Add suggestion for unsafe_op_in_unsafe_fn
- Fix unsafe checking of let expressions
Make the randomize feature of rustc_abi additive
The goal here is to make rust-analyzer able to build with the `rustc_private` versions of the rustc crates it depends on. See #116847
Make sure that predicates with unmentioned bound vars are still considered global in the old solver
In the old solver, we consider predicates with late-bound vars to not be "global":
9c8a2694fa/compiler/rustc_trait_selection/src/traits/select/mod.rs (L1840-L1844)
The implementation of `has_late_bound_vars` was modified in #115834 so that we'd properly anonymize binders that had late-bound vars but didn't reference them. This fixed an ICE.
However, this also led to a behavioral change in https://github.com/rust-lang/rust/issues/117056#issuecomment-1775014545 for a couple of crates, which now consider `for<'a> GL33: Shader` (note the binder var that is *not* used in the predicate) to not be "global". This forces associated types to not be normalizable due to the old trait solver being dumb.
This PR distinguishes types which *reference* late-bound vars and binders which *have* late-bound vars. The latter is represented with the new type flag `TypeFlags::HAS_BINDER_VARS`, which is used when we only care about knowing whether binders have vars in their bound var list (even if they're not used, like for binder anonymization).
This should fix (after beta backport) the `luminance-gl` and `luminance-webgl` crates in #117056.
r? types
**(priority is kinda high on a review here given beta becomes stable on November 16.)**
They've been deprecated for four years.
This commit includes the following changes.
- It eliminates the `rustc_plugin_impl` crate.
- It changes the language used for lints in
`compiler/rustc_driver_impl/src/lib.rs` and
`compiler/rustc_lint/src/context.rs`. External lints are now called
"loaded" lints, rather than "plugins" to avoid confusion with the old
plugins. This only has a tiny effect on the output of `-W help`.
- E0457 and E0498 are no longer used.
- E0463 is narrowed, now only relating to unfound crates, not plugins.
- The `plugin` feature was moved from "active" to "removed".
- It removes the entire plugins chapter from the unstable book.
- It removes quite a few tests, mostly all of those in
`tests/ui-fulldeps/plugin/`.
Closes#29597.
Fix incorrect trait bound restriction suggestion
Suggest
```
error[E0308]: mismatched types
--> $DIR/restrict-assoc-type-of-generic-bound.rs:9:12
|
LL | pub fn foo<A: MyTrait, B>(a: A) -> B {
| - - expected `B` because of return type
| |
| expected this type parameter
LL | return a.bar();
| ^^^^^^^ expected type parameter `B`, found associated type
|
= note: expected type parameter `B`
found associated type `<A as MyTrait>::T`
help: consider further restricting this bound
|
LL | pub fn foo<A: MyTrait<T = B>, B>(a: A) -> B {
| +++++++
```
instead of
```
error[E0308]: mismatched types
--> $DIR/restrict-assoc-type-of-generic-bound.rs:9:12
|
LL | pub fn foo<A: MyTrait, B>(a: A) -> B {
| - - expected `B` because of return type
| |
| expected this type parameter
LL | return a.bar();
| ^^^^^^^ expected type parameter `B`, found associated type
|
= note: expected type parameter `B`
found associated type `<A as MyTrait>::T`
help: consider further restricting this bound
|
LL | pub fn foo<A: MyTrait + <T = B>, B>(a: A) -> B {
| +++++++++
```
Fix#117501.
Suggest
```
error[E0308]: mismatched types
--> $DIR/restrict-assoc-type-of-generic-bound.rs:9:12
|
LL | pub fn foo<A: MyTrait, B>(a: A) -> B {
| - - expected `B` because of return type
| |
| expected this type parameter
LL | return a.bar();
| ^^^^^^^ expected type parameter `B`, found associated type
|
= note: expected type parameter `B`
found associated type `<A as MyTrait>::T`
help: consider further restricting this bound
|
LL | pub fn foo<A: MyTrait<T = B>, B>(a: A) -> B {
| +++++++
```
instead of
```
error[E0308]: mismatched types
--> $DIR/restrict-assoc-type-of-generic-bound.rs:9:12
|
LL | pub fn foo<A: MyTrait, B>(a: A) -> B {
| - - expected `B` because of return type
| |
| expected this type parameter
LL | return a.bar();
| ^^^^^^^ expected type parameter `B`, found associated type
|
= note: expected type parameter `B`
found associated type `<A as MyTrait>::T`
help: consider further restricting this bound
|
LL | pub fn foo<A: MyTrait + <T = B>, B>(a: A) -> B {
| +++++++++
```
Fix#117501.
use global cache when computing proof trees
we're writing the solver while relying on the existence of the global cache to avoid exponential blowup. By disabling the global cache when building proof trees, it is easy to get hangs, e.g. when computing intercrate ambiguity causes.
Removes the unstable `-Zdump_solver_proof_tree_use_cache` option, as we now always return a full proof tree.
r? `@compiler-errors`
Most notably, this commit changes the `pub use crate::*;` in that file
to `use crate::*;`. This requires a lot of `use` items in other crates
to be adjusted, because everything defined within `rustc_span::*` was
also available via `rustc_span::source_map::*`, which is bizarre.
The commit also removes `SourceMap::span_to_relative_line_string`, which
is unused.
Support enum variants in offset_of!
This MR implements support for navigating through enum variants in `offset_of!`, placing the enum variant name in the second argument to `offset_of!`. The RFC placed it in the first argument, but I think it interacts better with nested field access in the second, as you can then write things like
```rust
offset_of!(Type, field.Variant.field)
```
Alternatively, a syntactic distinction could be made between variants and fields (e.g. `field::Variant.field`) but I'm not convinced this would be helpful.
[RFC 3308 # Enum Support](https://rust-lang.github.io/rfcs/3308-offset_of.html#enum-support-offset_ofsomeenumstructvariant-field_on_variant)
Tracking Issue #106655.
Match usize/isize exhaustively with half-open ranges
The long-awaited finale to the saga of [exhaustiveness checking for integers](https://github.com/rust-lang/rust/pull/50912)!
```rust
match 0usize {
0.. => {} // exhaustive!
}
match 0usize {
0..usize::MAX => {} // helpful error message!
}
```
Features:
- Half-open ranges behave as expected for `usize`/`isize`;
- Trying to use `0..usize::MAX` will tell you that `usize::MAX..` is missing and explain why. No more unhelpful "`_` is missing";
- Everything else stays the same.
This should unblock https://github.com/rust-lang/rust/issues/37854.
Review-wise:
- I recommend looking commit-by-commit;
- This regresses perf because of the added complexity in `IntRange`; hopefully not too much;
- I measured each `#[inline]`, they all help a bit with the perf regression (tho I don't get why);
- I did not touch MIR building; I expect there's an easy PR there that would skip unnecessary comparisons when the range is half-open.
Rollup of 5 pull requests
Successful merges:
- #116267 (Some codegen cleanups around SIMD checks)
- #116712 (When encountering unclosed delimiters during lexing, check for diff markers)
- #117416 (Also consider TAIT to be uncomputable if the MIR body is tainted)
- #117421 (coverage: Replace impossible `coverage::Error` with assertions)
- #117438 (Do not ICE on constant evaluation failure in GVN.)
r? `@ghost`
`@rustbot` modify labels: rollup
Store #[deprecated] attribute's `since` value in parsed form
This PR implements the first followup bullet listed in https://github.com/rust-lang/rust/pull/117148#issue-1960240108.
We centralize error handling to the attribute parsing code in `compiler/rustc_attr/src/builtin.rs`, and thereby remove some awkward error codepaths from later phases of compilation that had to make sense of these #\[deprecated\] attributes, namely `compiler/rustc_passes/src/stability.rs` and `compiler/rustc_middle/src/middle/stability.rs`.
Rollup of 7 pull requests
Successful merges:
- #116862 (Detect when trait is implemented for type and suggest importing it)
- #117389 (Some diagnostics improvements of `gen` blocks)
- #117396 (Don't treat closures/coroutine types as part of the public API)
- #117398 (Correctly handle nested or-patterns in exhaustiveness)
- #117403 (Poison check_well_formed if method receivers are invalid to prevent typeck from running on it)
- #117411 (Improve some diagnostics around `?Trait` bounds)
- #117414 (Don't normalize to an un-revealed opaque when we hit the recursion limit)
r? `@ghost`
`@rustbot` modify labels: rollup
share some track_caller logic between interpret and codegen
Also move the code that implements the track_caller intrinsics out of the core interpreter engine -- it's just a helper creating a const-allocation, doesn't need to be part of the interpreter core.
See through aggregates in GVN
This PR is extracted from https://github.com/rust-lang/rust/pull/111344
The first 2 commit are cleanups to avoid repeated work. I propose to stop removing useless assignments as part of this pass, and let a later `SimplifyLocals` do it. This makes tests easier to read (among others).
The next 3 commits add a constant folding mechanism to the GVN pass, presented in https://github.com/rust-lang/rust/pull/116012. ~This pass is designed to only use global allocations, to avoid any risk of accidental modification of the stored state.~
The following commits implement opportunistic simplifications, in particular:
- projections of aggregates: `MyStruct { x: a }.x` gets replaced by `a`, works with enums too;
- projections of arrays: `[a, b][0]` becomes `a`;
- projections of repeat expressions: `[a; N][x]` becomes `a`;
- transform arrays of equal operands into a repeat rvalue.
Fixes https://github.com/rust-lang/miri/issues/3090
r? `@oli-obk`
Implement `gen` blocks in the 2024 edition
Coroutines tracking issue https://github.com/rust-lang/rust/issues/43122
`gen` block tracking issue https://github.com/rust-lang/rust/issues/117078
This PR implements `gen` blocks that implement `Iterator`. Most of the logic with `async` blocks is shared, and thus I renamed various types that were referring to `async` specifically.
An example usage of `gen` blocks is
```rust
fn foo() -> impl Iterator<Item = i32> {
gen {
yield 42;
for i in 5..18 {
if i.is_even() { continue }
yield i * 2;
}
}
}
```
The limitations (to be resolved) of the implementation are listed in the tracking issue
Fix ICE: Restrict param constraint suggestion
When encountering an associated item with a type param that could be constrained, do not look at the parent item if the type param comes from the associated item.
Fix#117209, fix#89868.
Stash and cancel cycle errors for auto trait leakage in opaques
We don't need to emit a traditional cycle error when we have a selection error that explains what's going on but in more detail.
We may want to augment this error to actually point out the cycle, now that the cycle error is not being emitted. We could do that by storing the set of opaques that was in the `CyclePlaceholder` that gets returned from `type_of_opaque`.
r? `@oli-obk` cc `@estebank` #117235
Rework negative coherence to properly consider impls that only partly overlap
This PR implements a modified negative coherence that handles impls that only have partial overlap.
It does this by:
1. taking both impl trait refs, instantiating them with infer vars
2. equating both trait refs
3. taking the equated trait ref (which represents the two impls' intersection), and resolving any vars
4. plugging all remaining infer vars with placeholder types
these placeholder-plugged trait refs can then be used normally with the new trait solver, since we no longer have to worry about the issue with infer vars in param-envs.
We use the **new trait solver** to reason correctly about unnormalized trait refs (due to deferred projection equality), since this avoid having to normalize anything under param-envs with infer vars in them.
This PR then additionally:
* removes the `FnPtr` knowable hack by implementing proper negative `FnPtr` trait bounds for rigid types.
---
An example:
Consider these two partially overlapping impls:
```
impl<T, U> PartialEq<&U> for &T where T: PartialEq<U> {}
impl<F> PartialEq<F> for F where F: FnPtr {}
```
Under the old algorithm, we would take one of these impls and replace it with infer vars, then try unifying it with the other impl under identity substitutions. This is not possible in either direction, since it either sets `T = U`, or tries to equate `F = &?0`.
Under the new algorithm, we try to unify `?0: PartialEq<?0>` with `&?1: PartialEq<&?2>`. This gives us `?0 = &?1 = &?2` and thus `?1 = ?2`. The intersection of these two trait refs therefore looks like: `&?1: PartialEq<&?1>`. After plugging this with placeholders, we get a trait ref that looks like `&!0: PartialEq<&!0>`, with the first impl having substs `?T = ?U = !0` and the second having substs `?F = &!0`[^1].
Then we can take the param-env from the first impl, and try to prove the negated where clause of the second.
We know that `&!0: !FnPtr` never holds, since it's a rigid type that is also not a fn ptr, we successfully detect that these impls may never overlap.
[^1]: For the purposes of this example, I just ignored lifetimes, since it doesn't really matter.
Rename AsyncCoroutineKind to CoroutineSource
pulled out of https://github.com/rust-lang/rust/pull/116447
Also refactors the printing infra of `CoroutineSource` to be ready for easily extending it with a `Gen` variant for `gen` blocks
Uplift `Canonical` to `rustc_type_ir`
I plan on moving the new trait solver's canonicalizer into either `rustc_type_ir` or a child crate. One dependency on this is lifting `Canonical<V>` to `rustc_type_ir` so we can actually name the canonicalized values.
I may also later lift `CanonicalVarInfo` into the new trait solver. I can't really tell what other changes need to be done, but I'm just putting this up sooner than later since I'm almost certain it'll need to be done regardless of other design choices.
There are a couple of warts introduced by this PR, since we no longer can define inherent `Canonical` impls in `rustc_middle` -- see the changes to:
* `compiler/rustc_trait_selection/src/traits/query/normalize.rs`
* `compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs`
r? lcnr
Uplift `ClauseKind` and `PredicateKind` into `rustc_type_ir`
Uplift `ClauseKind` and `PredicateKind` into `rustc_type_ir`.
Blocked on #116951
r? `@ghost`
Get rid of `'tcx` lifetime on `ConstVid`, `EffectVid`
These are simply newtyped numbers, so don't really have a reason (per se) to have a lifetime -- `TyVid` and `RegionVid` do not, for example.
The only consequence of this is that we need to use a new key type for `UnifyKey` that mentions `'tcx`. This is already done for `RegionVid`, with `RegionVidKey<'tcx>`, but this `UnifyKey` trait implementation may have been the original reason to give `ConstVid` a lifetime. See the changes to `compiler/rustc_middle/src/infer/unify_key.rs` specifically.
I consider the code cleaner this way, though -- we removed quite a few unnecessary `'tcx` in the process. This also makes it easier to uplift these two ids to `rustc_type_ir`, which I plan on doing in a follow-up PR.
r? `@BoxyUwU`
`OptWithInfcx` naming nits, trait bound simplifications
* Use an associated type `Interner` on `InferCtxtLike` to remove a redundant interner parameter (`I: Interner, Infcx: InferCtxtLike<I>` -> `Infcx: InferCtxtLike`).
* Remove double-`Option` between `infcx: Option<Infcx>` and `fn universe_of_ty(&self, ty: ty::InferTy) -> Option<ty::UniverseIndex>`. We don't need the infcx to be optional if we can provide a "noop" (`NoInfcx`) implementation that just always returns `None` for universe index.
* Also removes the `core::convert::Infallible` implementation which I found a bit weird...
* Some naming nits with params.
* I found `InferCtxt` + `InfCtx` and `Infcx` to be a lot of different ways to spell "inference context", so I got rid of the `InfCtx` type parameter name in favor of `Infcx` which is a more standard name.
* I found `OptWithInfcx` to be a bit redundant -> `WithInfcx`.
I'm making these changes because I intend to reuse the `InferCtxtLike` trait for uplifting the canonicalizer into a new trait -- conveniently, the information I need for uplifting the canonicalizer also is just the universe information of a type var, so it's super convenient 😸
r? `@BoxyUwU` or `@lcnr`
Rollup of 6 pull requests
Successful merges:
- #107159 (rand use getrandom for freebsd (available since 12.x))
- #116859 (Make `ty::print::Printer` take `&mut self` instead of `self`)
- #117046 (return unfixed len if pat has reported error)
- #117070 (rustdoc: wrap Type with Box instead of Generics)
- #117074 (Remove smir from triage and add me to stablemir)
- #117086 (Update .mailmap to promote my livename)
r? `@ghost`
`@rustbot` modify labels: rollup
Make `ty::print::Printer` take `&mut self` instead of `self`
based on #116815
This simplifies the code by removing all the `self` assignments and
makes the flow of data clearer - always into the printer.
Especially in v0 mangling, which already used `&mut self` in some
places, it gets a lot more uniform.
report `unused_import` for empty reexports even it is pub
Fixes#116032
An easy fix. r? `@petrochenkov`
(Discovered this issue while reviewing #115993.)
Implement jump threading MIR opt
This pass is an attempt to generalize `ConstGoto` and `SeparateConstSwitch` passes into a more complete jump threading pass.
This pass is rather heavy, as it performs a truncated backwards DFS on MIR starting from each `SwitchInt` terminator. This backwards DFS remains very limited, as it only walks through `Goto` terminators.
It is build to support constants and discriminants, and a propagating through a very limited set of operations.
The pass successfully manages to disentangle the `Some(x?)` use case and the DFA use case. It still needs a few tests before being ready.
Avoid a `track_errors` by bubbling up most errors from `check_well_formed`
I believe `track_errors` is mostly papering over issues that a sufficiently convoluted query graph can hit. I made this change, while the actual change I want to do is to stop bailing out early on errors, and instead use this new `ErrorGuaranteed` to invoke `check_well_formed` for individual items before doing all the `typeck` logic on them.
This works towards resolving https://github.com/rust-lang/rust/issues/97477 and various other ICEs, as well as allowing us to use parallel rustc more (which is currently rather limited/bottlenecked due to the very sequential nature in which we do `rustc_hir_analysis::check_crate`)
cc `@SparrowLii` `@Zoxc` for the new `try_par_for_each_in` function
coverage: Emit mappings for unused functions without generating stubs
For a while I've been annoyed by the fact that generating coverage maps for unused functions involves generating a stub function at the LLVM level.
As I suspected, generating that stub function isn't actually necessary, as long as we specifically tell LLVM about the symbol names of all the functions that have coverage mappings but weren't codegenned (due to being unused).
---
There is some helper code that gets moved around in the follow-up patches, so look at the first patch to see the most important functional changes.
---
`@rustbot` label +A-code-coverage
This simplifies the code by removing all the `self` assignments and
makes the flow of data clearer - always into the printer.
Especially in v0 mangling, which already used `&mut self` in some
places, it gets a lot more uniform.
This query has a name that sounds general-purpose, but in fact it has
coverage-specific semantics, and (fortunately) is only used by coverage code.
Because it is only ever called once (from one designated CGU), it doesn't need
to be a query, and we can change it to a regular function instead.
Uplift movability and mutability, the simple way
Just make type_ir a dependency of ast. This can be relaxed later if we want to make the dependency less heavy. Part of rust-lang/types-team#124.
r? `@lcnr` or `@jackh726`
coverage: Move most per-function coverage info into `mir::Body`
Currently, all of the coverage information collected by the `InstrumentCoverage` pass is smuggled through MIR in the form of individual `StatementKind::Coverage` statements, which must then be reassembled by coverage codegen.
That's awkward for a number of reasons:
- While some of the coverage statements do care about their specific position in the MIR control-flow graph, many of them don't, and are just tacked onto the function's first BB as metadata carriers.
- MIR inlining can result in coverage statements being duplicated, so coverage codegen has to jump through hoops to avoid emitting duplicate mappings.
- MIR optimizations that would delete coverage statements need to carefully copy them into the function's first BB so as not to omit them from coverage reports.
- The order in which coverage codegen sees coverage statements is dependent on MIR optimizations/inlining, which can cause unnecessary churn in the emitted coverage mappings.
- We don't have a good way to annotate MIR-level functions with extra coverage info that doesn't belong in a statement.
---
This PR therefore takes most of the per-function coverage info and stores it in a field in `mir::Body` as `Option<Box<FunctionCoverageInfo>>`.
(This adds one pointer to the size of `mir::Body`, even when coverage is not enabled.)
Coverage statements still need to be injected into MIR in some cases, but only when they actually affect codegen (counters) or are needed to detect code that has been optimized away as unreachable (counters/expressions).
---
By the end of this PR, the information stored in `FunctionCoverageInfo` is:
- A hash of the function's source code (needed by LLVM's coverage map format)
- The number of coverage counters added by coverage instrumentation
- A table of coverage expressions, associating each expression ID with its operator (add or subtract) and its two operands
- The list of mappings, associating each covered code region with a counter/expression/zero value
---
~~This is built on top of #115301, so I'll rebase and roll a reviewer once that lands.~~
r? `@ghost`
`@rustbot` label +A-code-coverage
This new description reflects the changes made in this PR, and should hopefully
be more useful to non-coverage developers who need to care about coverage
statements.
Even though expression details are now stored in the info structure, we still
need to inject `ExpressionUsed` statements into MIR, because if one is missing
during codegen then we know that it was optimized out and we can remap all of
its associated code regions to zero.
Previously, mappings were attached to individual coverage statements in MIR.
That necessitated special handling in MIR optimizations to avoid deleting those
statements, since otherwise codegen would be unable to reassemble the original
list of mappings.
With this change, a function's list of mappings is now attached to its MIR
body, and survives intact even if individual statements are deleted by
optimizations.
Don't compare host param by name
Seems sketchy to be searching for `sym::host` by name, especially when we can get the actual index with not very much work.
r? fee1-dead
Coverage codegen can now allocate arrays based on the number of
counters/expressions originally used by the instrumentor.
The existing query that inspects coverage statements is still used for
determining the number of counters passed to `llvm.instrprof.increment`. If
some high-numbered counters were removed by MIR optimizations, the instrumented
binary can potentially use less memory and disk space at runtime.
This allows coverage information to be attached to the function as a whole when
appropriate, instead of being smuggled through coverage statements in the
function's basic blocks.
As an example, this patch moves the `function_source_hash` value out of
individual `CoverageKind::Counter` statements and into the per-function info.
When synthesizing unused functions for coverage purposes, the absence of this
info is taken to indicate that a function was not eligible for coverage and
should not be synthesized.
Remove lots of generics from `ty::print`
All of these generics mostly resolve to the same thing, which means we can remove them, greatly simplifying the types involved in pretty printing and unlocking another simplification (that is not performed in this PR): Using `&mut self` instead of passing `self` through the return type.
cc `@eddyb` you probably know why it's like this, just checking in and making sure I didn't do anything bad
r? oli-obk
These are `Self` in almost all printers except one, which can just store
the state as a field instead. This simplifies the printer and allows for
further simplifications, for example using `&mut self` instead of
passing around the printer.
THIR unsafety checking was getting a cycle of
function unsafety checking
-> building THIR for the function
-> evaluating pattern inline constants in the function
-> building MIR for the inline constant
-> checking unsafety of functions (so that THIR can be stolen)
This is fixed by not stealing THIR when generating MIR but instead when
unsafety checking.
This leaves an issue with pattern inline constants not being unsafety
checked because they are evaluated away when generating THIR.
To fix that we now represent inline constants in THIR patterns and
visit them in THIR unsafety checking.
don't UB on dangling ptr deref, instead check inbounds on projections
This implements https://github.com/rust-lang/reference/pull/1387 in Miri. See that PR for what the change is about.
Detecting dangling references in `let x = &...;` is now done by validity checking only, so some tests need to have validity checking enabled. There is no longer inherently a "nodangle" check in evaluating the expression `&*ptr` (aside from the aliasing model).
r? `@oli-obk`
Based on:
- https://github.com/rust-lang/reference/pull/1387
- https://github.com/rust-lang/rust/pull/115524
interpret: clean up AllocBytes
Fixes https://github.com/rust-lang/miri/issues/2836
Nothing has moved here in half a year, so let's just remove these unused stubs -- they need a proper re-design anyway.
r? `@oli-obk`
Format all the let-chains in compiler crates
Since rust-lang/rustfmt#5910 has landed, soon we will have support for formatting let-chains (as soon as rustfmt syncs and beta gets bumped).
This PR applies the changes [from master rustfmt to rust-lang/rust eagerly](https://rust-lang.zulipchat.com/#narrow/stream/122651-general/topic/out.20formatting.20of.20prs/near/374997516), so that the next beta bump does not have to deal with a 200+ file diff and can remain concerned with other things like `cfg(bootstrap)` -- #113637 was a pain to land, for example, because of let-else.
I will also add this commit to the ignore list after it has landed.
The commands that were run -- I'm not great at bash-foo, but this applies rustfmt to every compiler crate, and then reverts the two crates that should probably be formatted out-of-tree.
```
~/rustfmt $ ls -1d ~/rust/compiler/* | xargs -I@ cargo run --bin rustfmt -- `@/src/lib.rs` --config-path ~/rust --edition=2021 # format all of the compiler crates
~/rust $ git checkout HEAD -- compiler/rustc_codegen_{gcc,cranelift} # revert changes to cg-gcc and cg-clif
```
cc `@rust-lang/rustfmt`
r? `@WaffleLapkin` or `@Nilstrieb` who said they may be able to review this purely mechanical PR :>
cc `@Mark-Simulacrum` and `@petrochenkov,` who had some thoughts on the order of operations with big formatting changes in https://github.com/rust-lang/rust/pull/95262#issue-1178993801. I think the situation has changed since then, given that let-chains support exists on master rustfmt now, and I'm fairly confident that this formatting PR should land even if *bootstrap* rustfmt doesn't yet format let-chains in order to lessen the burden of the next beta bump.
Relate alias ty with variance
In the new solver, turns out that the subst-relate branch of the alias-relate predicate was relating args invariantly even for opaques, which have variance 💀.
This change is a bit more invasive, but I'd rather not special-case it [here](aeaa5c30e5/compiler/rustc_trait_selection/src/solve/alias_relate.rs (L171-L190)) and then have it break elsewhere. I'm doing a perf run to see if the extra call to `def_kind` is that expensive, if it is, I'll reconsider.
r? ``@lcnr``
Extend `impl`'s `def_span` to include its where clauses
Typically, we highlight the def-span of an impl in a diagnostic due to either:
1. coherence error
2. trait evaluation cycle
3. invalid implementation of built-in trait
I find that an impl's where clauses are very often required to understanding why these errors come about, which is unfortunate since where clauses may be located on different lines and don't show up in the error. This PR expands the def-span of impls to include these where clauses.
r? cjgillot since you've touched this code a while back to make some spans shorter, but you can also reassign to wg-diagnostics or compiler if you're busy or have no strong opinions.
improve the suggestion of `generic_bound_failure`
- Fixes#115375
- suggest the bound in the correct scope: trait or impl header vs assoc item. See `tests/ui/suggestions/lifetimes/type-param-bound-scope.rs`
- don't suggest a lifetime name that conflicts with the other late-bound regions of the function:
```rust
type Inv<'a> = *mut &'a ();
fn check_bound<'a, T: 'a>(_: T, _: Inv<'a>) {}
fn test<'a, T>(_: &'a str, t: T, lt: Inv<'_>) { // suggests a new name `'a`
check_bound(t, lt); //~ ERROR
}
```
Generalize small dominators optimization
* Use small dominators optimization from 640ede7b0a more generally.
* Merge `DefLocation` and `LocationExtended` since they serve the same purpose.
remove Key impls for types that involve an AllocId
I don't understand how but somehow that leads to issues like https://github.com/rust-lang/rust/issues/83085? Anyway removing unused impls doesn't seem like a bad idea. The concerning part is that of course nothing will stop us from having such impls again in the future, alongside re-introducing bugs like #83085.
r? `@oli-obk`
Bring back generic parameters for indices in rustc_abi and make it compile on stable
This effectively reverses https://github.com/rust-lang/rust/pull/107163, allowing rust-analyzer to depend on this crate again,
It also moves some glob imports / expands them in the first commit because they made it more difficult for me to reason about things.
The word "active" is currently used in two different and confusing ways:
- `ACTIVE_FEATURES` actually means "available unstable features"
- `Features::active_features` actually means "features declared in the
crate's code", which can include feature within `ACTIVE_FEATURES` but
also others.
(This is also distinct from "enabled" features which includes declared
features but also some edition-specific features automatically enabled
depending on the edition in use.)
This commit changes the `Features::active_features` to
`Features::declared_features` which actually matches its meaning.
Likewise, `Features::active` becomes `Features::declared`.
Remove the `TypedArena::alloc_from_iter` specialization.
It was added in #78569. It's complicated and doesn't actually help
performance.
r? `@cjgillot`
All other impls replace type generics with `()` (or a type implementing the necessery traits)
and lifetimes with `'static`, do the same for those impls.
coverage: Allow each coverage statement to have multiple code regions
The original implementation of coverage instrumentation was built around the assumption that a coverage counter/expression would be associated with *up to one* code region. When it was discovered that *multiple* regions would sometimes need to share a counter, a workaround was found: for the remaining regions, the instrumentor would create a fresh expression that adds zero to the existing counter/expression.
That got the job done, but resulted in some awkward code, and produces unnecessarily complicated coverage maps in the final binary.
---
This PR removes that tension by changing `StatementKind::Coverage`'s code region field from `Option<CodeRegion>` to `Vec<CodeRegion>`.
The changes on the codegen side are fairly straightforward. As long as each `CoverageKind::Counter` only injects one `llvm.instrprof.increment`, the rest of coverage codegen is happy to handle multiple regions mapped to the same counter/expression, with only minor option-to-vec adjustments.
On the instrumentor/mir-transform side, we can get rid of the code that creates extra (x + 0) expressions. Instead we gather all of the code regions associated with a single BCB, and inject them all into one coverage statement.
---
There are several patches here but they can be divided in to three phases:
- Preparatory work
- Actually switching over to multiple regions per coverage statement
- Cleaning up
So viewing the patches individually may be easier.
a small wf and clause cleanup
- remove `Clause::from_projection_clause`, instead use `ToPredicate`
- change `predicate_obligations` to directly take a `Clause`
- remove some unnecessary `&`
- use clause in `min_specialization` checks where easily applicable
Rollup of 5 pull requests
Successful merges:
- #115863 (Add check_unused_messages in tidy)
- #116210 (Ensure that `~const` trait bounds on associated functions are in const traits or impls)
- #116358 (Rename both of the `Match` relations)
- #116371 (Remove unused features from `rustc_llvm`.)
- #116374 (Print normalized ty)
r? `@ghost`
`@rustbot` modify labels: rollup
When these methods were originally written, I wasn't aware that
`newtype_index!` already supports addition with ordinary numbers, without
needing to unwrap and re-wrap.
Cleanup number handling in match exhaustiveness
Doing a little bit of cleanup; handling number constants was somewhat messy. In particular, this:
- evals float consts once instead of repetitively
- reduces `Constructor` from 88 bytes to 56 (`mir::Const` is big!)
The `fast_try_eval_bits` function was mostly constructed from inlining existing code but I don't fully understand it; I don't follow how consts work and are evaluated very well.
Assorted improvements for `rustc_middle::mir::traversal`
r? `@cjgillot`
I'm not _entirely_ sure about all changes, although I do like all of them. If you'd like I can drop some commits. Best reviewed on a commit-by-commit basis, I think, since they are fairly isolated.
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
```
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`
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
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.
Move `DepKind` to `rustc_query_system` and define it as `u16`
This moves the `DepKind` type to `rustc_query_system` where it's defined with an inner `u16` field. This decouples it from `rustc_middle` and is a step towards letting other crates define dep kinds. It also allows some type parameters to be removed. The `DepKind` trait is replaced with a `Deps` trait. That's used when some operations or information about dep kinds which is unavailable in `rustc_query_system` are still needed.
r? `@cjgillot`
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.
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.
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
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.
adjust ConstValue::Slice to work for arbitrary slice types
valtrees have already been assuming that this works; this PR makes it a reality. Also further restrict `ConstValue::Slice` to what it is actually used for; this even shrinks `ConstValue` from 32 to 24 bytes which is a nice win. :)
The alternative to this approach is to make `ConstValue::Slice` work really only for `&str`/`&[u8]` literals, and never return it in `op_to_const`. That would make `op_to_const` very clean. We could then even remove the `meta` field; the length would always be `data.inner().len()`. We could *almost* just use a `Symbol` instead of a `ConstAllocation`, but we have to support byte strings and there doesn't seem to be an interned representation of them (or rather, `ConstAllocation` *is* their interned representation). In this world, valtrees of slice reference types would then become noticeably more expensive to turn into a `ConstValue` -- but does that matter? Specifically for `&str`/`&[u8]` we could still use the optimized representation if we wanted.
If byte strings were already interned somewhere I'd gravitate towards the alternative, but the way things stand, we need a `ConstAllocation` case anyway to support byte strings, and then we might as well support arbitrary slices. (Or we say that byte strings don't get an optimized representation at all. Such a performance cliff between `str` and byte strings is probably unexpected, though due to the lack of interning for byte strings I think there might already be a performance cliff there.)
clean up unneeded `ToPredicate` impls
Part of #107250.
Removed all totally unused impls. And inlined two impls not need to satisify trait bound.
r? `@oli-obk`
miri: reduce code duplication in some SSE/SSE2 intrinsics
Reduces code duplication in the Miri implementation of some SSE and SSE2 using generics and rustc_const_eval helper functions.
There are also some other minor changes.
r? `@RalfJung`
Pretty-print argument-position impl trait to name it.
This removes a corner case.
RPIT and TAIT keep having no name, and it would be wrong to use the one in HIR (Ident::empty), so I make this case ICE.
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`
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`
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`
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`
nop_lift macros: ensure that we are using the right interner
Right now someone could put down the wrong list name when using these macros, and everything would still build. Nothing does a type-check to ensure that the `$set` contains element of type `Self::Lifted`. Let's fix that.
For lists this is fairly easy; for the other interners we need to unwrap some newtypes which makes this more complicated.
It's easier to pass it in to the one method that needs it
(`highlighting_region_vid`) than to store it in the type. This means
`RegionHighlightMode` can impl `Default`.
`#[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)
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`
Properly consider binder vars in `HasTypeFlagsVisitor`
Given a PolyTraitRef like `for<'a> Ty: Trait` (where neither `Ty` nor `Trait` mention `'a`), we do *not* return true for `.has_type_flags(TypeFlags::HAS_LATE_BOUND)`, even though binders are supposed to act as if they have late-bound vars even if they don't mention them in their bound value: 31ae3b2bdb. This is because we use `HasTypeFlagsVisitor`, which only computes the type flags for `Ty`, `Const` and `Region` and `Predicates`, and we consequently skip any binders (and setting flags for their vars) that are not contained in one of these types.
This ends up causing a problem, because when we call `TyCtxt::erase_regions` (which both erases regions *and* anonymizes bound vars), we will skip such a PolyTraitRef, not anonymizing it, and therefore not making it structurally equal to other binders. This breaks vtable computations.
This PR computes the flags for all binders we enter in `HasTypeFlagsVisitor` if we're looking for `TypeFlags::HAS_LATE_BOUND` (or `TypeFlags::HAS_{RE,TY,CT}_LATE_BOUND`).
Fixes#115807
treat host effect params as erased in codegen
This fixes the changes brought to codegen tests when effect params are added to libcore, by not attempting to monomorphize functions that get the host param by being `const fn`.
r? `@oli-obk`
some ConstValue refactoring
In particular, use AllocId instead of Allocation in ConstValue::ByRef. This helps avoid redundant AllocIds when a `ByRef` constant gets put back into the interpreter.
r? `@oli-obk`
Fixes https://github.com/rust-lang/rust/issues/105536
This fixes the changes brought to codegen tests when effect params are
added to libcore, by not attempting to monomorphize functions that get
the host param by being `const fn`.
some inspect improvements
split from #114810 because I still want to experiment a bunch with that PR and these changes are self-contained.
r? `@compiler-errors`
Rework `no_coverage` to `coverage(off)`
As discussed at the tail of https://github.com/rust-lang/rust/issues/84605 this replaces the `no_coverage` attribute with a `coverage` attribute that takes sub-parameters (currently `off` and `on`) to control the coverage instrumentation.
Allows future-proofing for things like `coverage(off, reason="Tested live", issue="#12345")` or similar.
Remove `verbose_generic_activity_with_arg`
This removes `verbose_generic_activity_with_arg` and changes users to `generic_activity_with_arg`. This keeps the output of `-Z time` readable while these repeated events are still available with the self profiling mechanism.
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
Co-authored-by: León Orell Valerian Liehr <me@fmease.dev>
Co-authored-by: Michael Goulet <michael@errs.io>
interpret: change ABI-compat test to be type-based
This makes the test consistent across targets. Otherwise the chances are very high that ABI mismatches get accepted on x86_64 but still fail on many other targets with more complicated ABIs.
This implements (most of) the rules described in https://github.com/rust-lang/rust/pull/115476.
also handle 2 panics when dumping proof trees for the whole test suite
- need to actually tell the proof tree builder about overflow
- need to handle a recursion_limit of 0 :<
Enable incremental-relative-spans by default.
This was enabled on nightly in https://github.com/rust-lang/rust/pull/84762.
It has been a while, without obvious bugs. It's time to enable it by default for incremental runs.
The `Debug` impl for `Ty` just calls the `Display` impl for `Ty`. This
is surprising and annoying. In particular, it means `Debug` doesn't show
as much information as `Debug` for `TyKind` does. And `Debug` is used in
some user-facing error messages, which seems bad.
This commit changes the `Debug` impl for `Ty` to call the `Debug` impl
for `TyKind`. It also does a number of follow-up changes to preserve
existing output, many of which involve inserting
`with_no_trimmed_paths!` calls. It also adds `Display` impls for
`UserType` and `Canonical`.
Some tests have changes to expected output:
- Those that use the `rustc_abi(debug)` attribute.
- Those that use the `EMIT_MIR` annotation.
In each case the output is slightly uglier than before. This isn't
ideal, but it's pretty weird (particularly for the attribute) that the
output is using `Debug` in the first place. They're fairly obscure
attributes (I hadn't heard of them) so I'm not worried by this.
For `async-is-unwindsafe.stderr`, there is one line that now lacks a
full path. This is a consistency improvement, because all the other
mentions of `Context` in this test lack a path.
Avoid a `source_span` query when encoding Spans into query results
This avoids a `source_span` query when encoding `Span`s into query results. It's not sound to execute queries here as the query caches can be locked and the dep graph is no longer writable.
r? `@cjgillot`
Use `Freeze` for `SourceFile`
This uses the `Freeze` type in `SourceFile` to let accessing `external_src` and `lines` be lock-free.
Behavior of `add_external_src` is changed to set `ExternalSourceKind::AbsentErr` on a hash mismatch which matches the documentation. `ExternalSourceKind::Unneeded` was removed as it's unused.
Based on https://github.com/rust-lang/rust/pull/115401.
Don't suggest dereferencing to unsized type
Rudimentary check that the self type is Sized. I don't really like any of this diagnostics code -- it's really messy and also really prone to false positives and negatives, but oh well.
Fixes#115569
Print the path of a return-position impl trait in trait when `return_type_notation` is enabled
When we're printing a return-position impl trait in trait, we usually just print it like an opaque. This is *usually* fine, but can be confusing when using `return_type_notation`. Print the path of the method from where the RPITIT originates when this feature gate is enabled.
Implement refinement lint for RPITIT
Implements a lint that warns against accidentally refining an RPITIT in an implementation. This is not a hard error, and can be suppressed with `#[allow(refining_impl_trait)]`, since this behavior may be desirable -- the lint just serves as an acknowledgement from the impl author that they understand that the types they write in the implementation are an API guarantee.
This compares bounds syntactically, not semantically -- semantic implication is more difficult and essentially relies on adding the ability to keep the RPITIT hidden in the trait system so that things can be proven about the type that shows up in the impl without its own bounds leaking through, either via a new reveal mode or something else. This was experimentally implemented in #111931.
Somewhat opinionated choices:
1. Putting the lint behind `refining_impl_trait` rather than a blanket `refine` lint. This could be changed, but I like keeping the lint specialized to RPITITs so the explanation can be tailored to it.
2. This PR does not include the `#[refine]` attribute or the feature gate, since it's kind of orthogonal and can be added in a separate PR.
r? `@oli-obk`
Use a specialized varint + bitpacking scheme for DepGraph encoding
The previous scheme here uses leb128 to encode the edge tables that represent the incr comp dependency graph. The problem with that scheme is that leb128 has overhead for larger values, and generally relies on the distribution of encoded values being heavily skewed towards smaller values. That is definitely not the case for a dep node index, since they are handed out sequentially and the whole range is covered, the distribution is actually biased in the opposite direction: Most dep nodes are large.
This PR implements a different varint encoding scheme. Instead of applying varint encoding to individual dep node indices (which is extremely branchy) we now apply it per node.
While being built, each node now stores its edges in a `SmallVec` with a bit of extra logic to track the max value of each edge. Then we varint encode the whole batch. This is a gamble: We save on space by only claiming 2 bits per node instead of ~3 bits per edge which is a nice savings but needs to balance out with the space overhead that a single large index in a node with a lot of edges will encode unnecessary bytes in each of that node's edge indices.
Then, to keep the runtime overhead of this encoding scheme down we deserialize our indices by loading 4 bytes for each then masking off the bytes that are't ours. This is much less code and branches than leb128, but relies on having some readable bytes past the end of each edge list. We explicitly add such padding to the in-memory data during decoding. And we also do this decoding lazily, turning a dense on-disk encoding into a peak memory reduction.
Then we apply a bit-packing scheme; since in https://github.com/rust-lang/rust/pull/115391 we now have unused bits on `DepKind`, we use those unused bits (currently there are 7!) to store the 2 bits that we need for the byte width of the edges in each node, then use the remaining bits to store the length of the edge list, if it fits.
r? `@nnethercote`
Represent MIR composite debuginfo as projections instead of aggregates
Composite debuginfo for MIR is currently represented as
```
debug name => Type { projection1 => place1, projection2 => place2 };
```
ie. a single `VarDebugInfo` object with that name, and its value a `VarDebugInfoContents::Composite`.
This PR proposes to reverse the representation to be
```
debug name.projection1 => place1;
debug name.projection2 => place2;
```
ie. multiple `VarDebugInfo` objects with each their projection.
This simplifies the handling of composite debuginfo by the compiler by avoiding weird nesting.
Based on https://github.com/rust-lang/rust/pull/115139
Add `FreezeLock` type and use it to store `Definitions`
This adds a `FreezeLock` type which allows mutation using a lock until the value is frozen where it can be accessed lock-free. It's used to store `Definitions` in `Untracked` instead of a `RwLock`. Unlike the current scheme of leaking read guards this doesn't deadlock if definitions is written to after no mutation are expected.
Use relative positions inside a SourceFile.
This allows to remove the normalization of start positions for hashing, and simplify allocation of global address space.
cc `@Zoxc`
Encode DepKind as u16
The derived Encodable/Decodable impls serialize/deserialize as a varint, which results in a lot of code size around the encoding/decoding of these types which isn't justified: The full range of values here is rather small but doesn't quite fit in to a `u8`. Growing _all_ serialized `DepKind` to 2 bytes costs us on average 1% size in the incr comp dep graph, which I plan to recoup in https://github.com/rust-lang/rust/pull/110050 by taking advantage of the unused bits in all the serialized `DepKind`.
r? `@nnethercote`
Make `get_return_block()` return `Some` only for HIR nodes in body
Fixes#114918
The issue occurred while compiling the following input:
```rust
fn uwu() -> [(); { () }] {
loop {}
}
```
It was caused by the code below trying to suggest a missing return type which resulted in a const eval cycle: 1bd043098e/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs (L68-L75)
The root cause was `get_return_block()` returning an `Fn` node for a node in the return type (i.e. the second `()` in the return type `[(); { () }]` of the input) although it is supposed to do so only for nodes that lie in the body of the function and return `None` otherwise (at least as per my understanding).
The PR fixes the issue by fixing this behaviour of `get_return_block()`.
Remove conditional use of `Sharded` from query state
`Sharded` is already a zero cost abstraction, so it shouldn't affect the performance of the single thread compiler if LLVM does its job.
r? `@cjgillot`
Allow explicit `#[repr(Rust)]`
This is identical to no `repr()` at all. For `Rust, packed` and `Rust, align(x)`, it should be the same as no `Rust` at all (as, afaik, `#[repr(align(16))]` uses the Rust ABI.)
The main use case for this is being able to explicitly say "I want to use the Rust ABI" in very very rare circumstances where the first obvious choice would be the C ABI yet is undesirable, which is already possible with functions as `extern "Rust"`. This would be useful for silencing https://github.com/rust-lang/rust-clippy/pull/11253. It's also more consistent with `extern`.
The lack of this also tripped me up a bit when I was new to Rust, as I expected this to be possible.
Point at return type when it influences non-first `match` arm
When encountering code like
```rust
fn foo() -> i32 {
match 0 {
1 => return 0,
2 => "",
_ => 1,
}
}
```
Point at the return type and not at the prior arm, as that arm has type `!` which isn't influencing the arm corresponding to arm `2`.
Fix#78124.
Couple of global state and driver refactors
* Remove some unused global mutable state
* Remove a couple of unnecessary queries (both driver and `TyCtxt` queries)
* Remove an unnecessary use of `FxIndexMap`
When encountering code like
```rust
fn foo() -> i32 {
match 0 {
1 => return 0,
2 => "",
_ => 1,
}
}
```
Point at the return type and not at the prior arm, as that arm has type
`!` which isn't influencing the arm corresponding to arm `2`.
Fix#78124.
feat: `riscv-interrupt-{m,s}` calling conventions
Similar to prior support added for the mips430, avr, and x86 targets this change implements the rough equivalent of clang's [`__attribute__((interrupt))`][clang-attr] for riscv targets, enabling e.g.
```rust
static mut CNT: usize = 0;
pub extern "riscv-interrupt-m" fn isr_m() {
unsafe {
CNT += 1;
}
}
```
to produce highly effective assembly like:
```asm
pub extern "riscv-interrupt-m" fn isr_m() {
420003a0: 1141 addi sp,sp,-16
unsafe {
CNT += 1;
420003a2: c62a sw a0,12(sp)
420003a4: c42e sw a1,8(sp)
420003a6: 3fc80537 lui a0,0x3fc80
420003aa: 63c52583 lw a1,1596(a0) # 3fc8063c <_ZN12esp_riscv_rt3CNT17hcec3e3a214887d53E.0>
420003ae: 0585 addi a1,a1,1
420003b0: 62b52e23 sw a1,1596(a0)
}
}
420003b4: 4532 lw a0,12(sp)
420003b6: 45a2 lw a1,8(sp)
420003b8: 0141 addi sp,sp,16
420003ba: 30200073 mret
```
(disassembly via `riscv64-unknown-elf-objdump -C -S --disassemble ./esp32c3-hal/target/riscv32imc-unknown-none-elf/release/examples/gpio_interrupt`)
This outcome is superior to hand-coded interrupt routines which, lacking visibility into any non-assembly body of the interrupt handler, have to be very conservative and save the [entire CPU state to the stack frame][full-frame-save]. By instead asking LLVM to only save the registers that it uses, we defer the decision to the tool with the best context: it can more accurately account for the cost of spills if it knows that every additional register used is already at the cost of an implicit spill.
At the LLVM level, this is apparently [implemented by] marking every register as "[callee-save]," matching the semantics of an interrupt handler nicely (it has to leave the CPU state just as it found it after its `{m|s}ret`).
This approach is not suitable for every interrupt handler, as it makes no attempt to e.g. save the state in a user-accessible stack frame. For a full discussion of those challenges and tradeoffs, please refer to [the interrupt calling conventions RFC][rfc].
Inside rustc, this implementation differs from prior art because LLVM does not expose the "all-saved" function flavor as a calling convention directly, instead preferring to use an attribute that allows for differentiating between "machine-mode" and "superivsor-mode" interrupts.
Finally, some effort has been made to guide those who may not yet be aware of the differences between machine-mode and supervisor-mode interrupts as to why no `riscv-interrupt` calling convention is exposed through rustc, and similarly for why `riscv-interrupt-u` makes no appearance (as it would complicate future LLVM upgrades).
[clang-attr]: https://clang.llvm.org/docs/AttributeReference.html#interrupt-risc-v
[full-frame-save]: 9281af2ecf/src/lib.rs (L440-L469)
[implemented by]: b7fb2a3fec/llvm/lib/Target/RISCV/RISCVRegisterInfo.cpp (L61-L67)
[callee-save]: 973f1fe7a8/llvm/lib/Target/RISCV/RISCVCallingConv.td (L30-L37)
[rfc]: https://github.com/rust-lang/rfcs/pull/3246
Similar to prior support added for the mips430, avr, and x86 targets
this change implements the rough equivalent of clang's
[`__attribute__((interrupt))`][clang-attr] for riscv targets, enabling
e.g.
```rust
static mut CNT: usize = 0;
pub extern "riscv-interrupt-m" fn isr_m() {
unsafe {
CNT += 1;
}
}
```
to produce highly effective assembly like:
```asm
pub extern "riscv-interrupt-m" fn isr_m() {
420003a0: 1141 addi sp,sp,-16
unsafe {
CNT += 1;
420003a2: c62a sw a0,12(sp)
420003a4: c42e sw a1,8(sp)
420003a6: 3fc80537 lui a0,0x3fc80
420003aa: 63c52583 lw a1,1596(a0) # 3fc8063c <_ZN12esp_riscv_rt3CNT17hcec3e3a214887d53E.0>
420003ae: 0585 addi a1,a1,1
420003b0: 62b52e23 sw a1,1596(a0)
}
}
420003b4: 4532 lw a0,12(sp)
420003b6: 45a2 lw a1,8(sp)
420003b8: 0141 addi sp,sp,16
420003ba: 30200073 mret
```
(disassembly via `riscv64-unknown-elf-objdump -C -S --disassemble ./esp32c3-hal/target/riscv32imc-unknown-none-elf/release/examples/gpio_interrupt`)
This outcome is superior to hand-coded interrupt routines which, lacking
visibility into any non-assembly body of the interrupt handler, have to
be very conservative and save the [entire CPU state to the stack
frame][full-frame-save]. By instead asking LLVM to only save the
registers that it uses, we defer the decision to the tool with the best
context: it can more accurately account for the cost of spills if it
knows that every additional register used is already at the cost of an
implicit spill.
At the LLVM level, this is apparently [implemented by] marking every
register as "[callee-save]," matching the semantics of an interrupt
handler nicely (it has to leave the CPU state just as it found it after
its `{m|s}ret`).
This approach is not suitable for every interrupt handler, as it makes
no attempt to e.g. save the state in a user-accessible stack frame. For
a full discussion of those challenges and tradeoffs, please refer to
[the interrupt calling conventions RFC][rfc].
Inside rustc, this implementation differs from prior art because LLVM
does not expose the "all-saved" function flavor as a calling convention
directly, instead preferring to use an attribute that allows for
differentiating between "machine-mode" and "superivsor-mode" interrupts.
Finally, some effort has been made to guide those who may not yet be
aware of the differences between machine-mode and supervisor-mode
interrupts as to why no `riscv-interrupt` calling convention is exposed
through rustc, and similarly for why `riscv-interrupt-u` makes no
appearance (as it would complicate future LLVM upgrades).
[clang-attr]: https://clang.llvm.org/docs/AttributeReference.html#interrupt-risc-v
[full-frame-save]: 9281af2ecf/src/lib.rs (L440-L469)
[implemented by]: b7fb2a3fec/llvm/lib/Target/RISCV/RISCVRegisterInfo.cpp (L61-L67)
[callee-save]: 973f1fe7a8/llvm/lib/Target/RISCV/RISCVCallingConv.td (L30-L37)
[rfc]: https://github.com/rust-lang/rfcs/pull/3246
Map RPIT duplicated lifetimes back to fn captured lifetimes
Use the [`lifetime_mapping`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_hir/hir/struct.OpaqueTy.html#structfield.lifetime_mapping) to map an RPIT's captured lifetimes back to the early- or late-bound lifetimes from its parent function. We may be going thru several layers of mapping, since opaques can be nested, so we introduce `TyCtxt::map_rpit_lifetime_to_fn_lifetime` to loop through several opaques worth of mapping, and handle turning it into a `ty::Region` as well.
We can then use this instead of the identity substs for RPITs in `check_opaque_meets_bounds` to address #114285.
We can then also use `map_rpit_lifetime_to_fn_lifetime` to properly install bidirectional-outlives predicates for both RPITs and RPITITs. This addresses #114601.
I based this on #114574, but I don't actually know how much of that PR we still need, so some code may be redundant now... 🤷
---
Fixes#114597Fixes#114579Fixes#114285
Also fixes#114601, since it turns out we had other bugs with RPITITs and their duplicated lifetime params 😅.
Supersedes #114574
r? `@oli-obk`
Store the laziness of type aliases in their `DefKind`
Previously, we would treat paths referring to type aliases as *lazy* type aliases if the current crate had lazy type aliases enabled independently of whether the crate which the alias was defined in had the feature enabled or not.
With this PR, the laziness of a type alias depends on the crate it is defined in. This generally makes more sense to me especially if / once lazy type aliases become the default in a new edition and we need to think about *edition interoperability*:
Consider the hypothetical case where the dependency crate has an older edition (and thus eager type aliases), it exports a type alias with bounds & a where-clause (which are void but technically valid), the dependent crate has the latest edition (and thus lazy type aliases) and it uses that type alias. Arguably, the bounds should *not* be checked since at any time, the dependency crate should be allowed to change the bounds at will with a *non*-major version bump & without negatively affecting downstream crates.
As for the reverse case (dependency: lazy type aliases, dependent: eager type aliases), I guess it rules out anything from slight confusion to mild annoyance from upstream crate authors that would be caused by the compiler ignoring the bounds of their type aliases in downstream crates with older editions.
---
This fixes#114468 since before, my assumption that the type alias associated with a given weak projection was lazy (and therefore had its variances computed) did not necessarily hold in cross-crate scenarios (which [I kinda had a hunch about](https://github.com/rust-lang/rust/pull/114253#discussion_r1278608099)) as outlined above. Now it does hold.
`@rustbot` label F-lazy_type_alias
r? `@oli-obk`
Add documentation to has_deref
Documentation of `has_deref` needed some polish to be more clear about where it should be used and what's it's purpose.
cc https://github.com/rust-lang/rust/issues/114401
r? `@RalfJung`
Convert builtin "global" late lints to run per module
The compiler currently has 4 non-incremental lints:
1. `clashing_extern_declarations`;
2. `missing_debug_implementations`;
3. ~`unnameable_test_items`;~ changed by https://github.com/rust-lang/rust/pull/114414
4. `missing_docs`.
Non-incremental lints get reexecuted for each compilation, which is slow. Moreover, those lints are allow-by-default, so run for nothing most of the time. This PR attempts to make them more incremental-friendly.
`clashing_extern_declarations` is moved to a standalone query.
`missing_debug_implementation` can use `non_blanket_impls_for_ty` instead of recomputing it.
`missing_docs` is harder as it needs to track if there is a `doc(hidden)` module surrounding. I hack around this using the lint level engine. That's easy to implement and allows to re-enable the lint for a re-exported module, while a more proper solution would reuse the same device as `unnameable_test_items`.
update overflow handling in the new trait solver
implements https://hackmd.io/QY0dfEOgSNWwU4oiGnVRLw?view. I want to clean up this doc and add it to the rustc-dev-guide, but I think this PR is ready for merge as is, even without the dev-guide entry.
r? `@compiler-errors`
Rework upcasting confirmation to support upcasting to fewer projections in target bounds
This PR implements a modified trait upcasting algorithm that is resilient to changes in the number of associated types in the bounds of the source and target trait objects.
It does this by equating each bound of the target trait ref individually against the bounds of the source trait ref, rather than doing them all together by constructing a new trait object.
#### The new way we do trait upcasting confirmation
1. Equate the target trait object's principal trait ref with one of the supertraits of the source trait object's principal.
fdcab310b2/compiler/rustc_trait_selection/src/traits/select/mod.rs (L2509-L2525)
2. Make sure that every auto trait in the *target* trait object is present in the source trait ref's bounds.
fdcab310b2/compiler/rustc_trait_selection/src/traits/select/mod.rs (L2559-L2562)
3. For each projection in the *target* trait object, make sure there is exactly one projection that equates with it in the source trait ref's bound. If there is more than one, bail with ambiguity.
fdcab310b2/compiler/rustc_trait_selection/src/traits/select/mod.rs (L2526-L2557)
* Since there may be more than one that applies, we probe first to check that there is exactly one, then we equate it outside of a probe once we know that it's unique.
4. Make sure the lifetime of the source trait object outlives the lifetime of the target.
<details>
<summary>Meanwhile, this is how we used to do upcasting:</summary>
1. For each supertrait of the source trait object, take that supertrait, append the source object's projection bounds, and the *target* trait object's auto trait bounds, and make this into a new object type:
d12c6e947c/compiler/rustc_trait_selection/src/traits/select/confirmation.rs (L915-L929)
2. Then equate it with the target trait object:
d12c6e947c/compiler/rustc_trait_selection/src/traits/select/confirmation.rs (L936)
This will be a type mismatch if the target trait object has fewer projection bounds, since we compare the bounds structurally in relate:
d12c6e947c/compiler/rustc_middle/src/ty/relate.rs (L696-L698)
</details>
Fixes#114035
Also fixes#114113, because I added a normalize call in the old solver.
r? types
resolve before canonicalization in new solver, ICE if unresolved
Fold the values with a resolver before canonicalization instead of making it happen within canonicalization.
This allows us to filter trivial region constraints from the external constraints.
r? ``@lcnr``
Perform OpaqueCast field projection on HIR, too.
fixes#105819
This is necessary for closure captures in 2021 edition, as they capture individual fields, not the full mentioned variables. So it may try to capture a field of an opaque (because the hidden type is known to be something with a field).
See https://github.com/rust-lang/rust/pull/99806 for when and why we added OpaqueCast to MIR.
Add `internal_features` lint
Implements https://github.com/rust-lang/compiler-team/issues/596
Also requires some more test blessing for codegen tests etc
`@jyn514` had the idea of just `allow`ing the lint by default in the test suite. I'm not sure whether this is a good idea, but it's definitely one worth considering. Additional input encouraged.
const validation: point at where we found a pointer but expected an integer
Instead of validation just printing "unable to turn pointer into bytes", make this a regular validation error that says where in the value the bad pointer was found. Also distinguish "expected integer, got pointer" from "expected pointer, got partial pointer or mix of pointers".
To avoid duplicating things too much I refactored the diagnostics for validity a bit, so that "got uninit, expected X" and "got pointer, expected X" can share the "X" part. Also all the errors emitted for validation are now grouped under `const_eval_validation` so that they are in a single group in the ftl file.
r? `@oli-obk`
It lints against features that are inteded to be internal to the
compiler and standard library. Implements MCP #596.
We allow `internal_features` in the standard library and compiler as those
use many features and this _is_ the standard library from the "internal to the compiler and
standard library" after all.
Marking some features as internal wasn't exactly the most scientific approach, I just marked some
mostly obvious features. While there is a categorization in the macro,
it's not very well upheld (should probably be fixed in another PR).
We always pass `-Ainternal_features` in the testsuite
About 400 UI tests and several other tests use internal features.
Instead of throwing the attribute on each one, just always allow them.
There's nothing wrong with testing internal features^^
Miri: fix error on dangling pointer inbounds offset
We used to claim that the pointer was "dereferenced", but that is just not true.
Can be reviewed commit-by-commit. The first commit is an unrelated rename that didn't seem worth splitting into its own PR.
r? `@oli-obk`
Don't check unnecessarily that impl trait is RPIT
We have this random `return_type_impl_trait` function to detect if a function returns an RPIT which is used in outlives suggestions, but removing it doesn't actually change any diagnostics. Let's just remove it.
Also, suppress a spurious outlives error from a ReError.
Fixes#114274
Operand types are now tracked explicitly, so there is no need to reserve ID 0
for the special always-zero counter.
As part of the renumbering, this change fixes an off-by-one error in the way
counters were counted by the `coverageinfo` query. As a result, functions
should now have exactly the number of counters they actually need, instead of
always having an extra counter that is never used.
Operand types are now tracked explicitly, so there is no need for expression
IDs to avoid counter IDs by descending from `u32::MAX`. Instead they can just
count up from 0, and can be used directly as indices when necessary.
Because the three kinds of operand are now distinguished explicitly, we no
longer need fiddly code to disambiguate counter IDs and expression IDs based on
the total number of counters/expressions in a function.
This does increase the size of operands from 4 bytes to 8 bytes, but that
shouldn't be a big deal since they are mostly stored inside boxed structures,
and the current coverage code is not particularly size-optimized anyway.
The actual motivation here is to prevent `rustfmt` from suddenly reformatting
these enum variants onto a single line, when they become slightly shorter in
the future.
But there's no harm in adding some helpful documentation at the same time.
Map RPITIT's opaque type bounds back from projections to opaques
An RPITIT in a program's AST is eventually translated into both a projection GAT and an opaque. The opaque is used for default trait methods, like:
```
trait Foo {
fn bar() -> impl Sized { 0i32 }
}
```
The item bounds for both the projection and opaque are identical, and both have a *projection* self ty. This is mostly okay, since we can normalize this projection within the default trait method body to the opaque, but it does two things:
1. it leads to bugs in places where we don't normalize item bounds, like `deduce_future_output_from_obligations`
2. it leads to extra match arms that are both suspicious looking and also easy to miss
This PR maps the opaque type bounds of the RPITIT's *opaque* back to the opaque's self type to avoid this quirk. Then we can fix the UI test for #108304 (1.) and also remove a bunch of match arms (2.).
Fixes#108304
r? `@spastorino`
Rollup of 7 pull requests
Successful merges:
- #114099 (privacy: no nominal visibility for assoc fns )
- #114128 (When flushing delayed span bugs, write to the ICE dump file even if it doesn't exist)
- #114138 (Adjust spans correctly for fn -> method suggestion)
- #114146 (Skip reporting item name when checking RPITIT GAT's associated type bounds hold)
- #114147 (Insert RPITITs that were shadowed by missing ADTs that resolve to [type error])
- #114155 (Replace a lazy `RefCell<Option<T>>` with `OnceCell<T>`)
- #114164 (Add regression test for `--cap-lints allow` and trait bounds warning)
r? `@ghost`
`@rustbot` modify labels: rollup
When `staged_api` is enabled, effective visibilities are computed earlier
and this can trigger an ICE in some cases.
In particular, if a impl of a trait method has a visibility then an error
will be reported for that, but when privacy invariants are being checked,
the effective visibility will still be greater than the nominal visbility
and that will trigger a `span_bug!`.
However, this invariant - that effective visibilites are limited to
nominal visibility - doesn't make sense for associated functions.
Signed-off-by: David Wood <david@davidtw.co>
new unstable option: -Zwrite-long-types-to-disk
This option guards the logic of writing long type names in files and instead using short forms in error messages in rustc_middle/ty/error behind a flag. The main motivation for this change is to disable this behaviour when running ui tests.
This logic can be triggered by running tests in a directory that has a long enough path, e.g. /my/very-long-path/where/rust-codebase/exists/
This means ui tests can fail depending on how long the path to their file is.
Some ui tests actually rely on this behaviour for their assertions, so for those we enable the flag manually.
Normalize the RHS of an `Unsize` goal in the new solver
`Unsize` goals are... tricky. Not only do they structurally match on their self type, but they're also structural on their other type parameter. I'm pretty certain that it is both incomplete and also just plain undesirable to not consider normalizing the RHS of an unsize goal. More practically, I'd like for this code to work:
```rust
trait A {}
trait B: A {}
impl A for usize {}
impl B for usize {}
trait Mirror {
type Assoc: ?Sized;
}
impl<T: ?Sized> Mirror for T {
type Assoc = T;
}
fn main() {
// usize: Unsize<dyn B>
let x = Box::new(1usize) as Box<<dyn B as Mirror>::Assoc>;
// dyn A: Unsize<dyn B>
let y = x as Box<<dyn A as Mirror>::Assoc>;
}
```
---
In order to achieve this, we add `EvalCtxt::normalize_non_self_ty` (naming modulo bikeshedding), which *must* be used for all non-self type arguments that are structurally matched in candidate assembly. Currently this is only necessary for `Unsize`'s argument, but I could see future traits requiring this (hopefully rarely) in the future. It uses `repeat_while_none` to limit infinite looping, and normalizes the self type until it is no longer an alias.
Also, we need to fix feature gate detection for `trait_upcasting` and `unsized_tuple_coercion` when HIR typeck has unnormalized types. We can do that by checking the `ImplSource` returned by selection, which necessitates adding a new impl source for tuple upcasting.
interpret: Unify projections for MPlaceTy, PlaceTy, OpTy
For ~forever, we didn't really have proper shared code for handling projections into those three types. This is mostly because `PlaceTy` projections require `&mut self`: they might have to `force_allocate` to be able to represent a project part-way into a local.
This PR finally fixes that, by enhancing `Place::Local` with an `offset` so that such an optimized place can point into a part of a place without having requiring an in-memory representation. If we later write to that place, we will still do `force_allocate` -- for now we don't have an optimized path in `write_immediate` that would avoid allocation for partial overwrites of immediately stored locals. But in `write_immediate` we have `&mut self` so at least this no longer pollutes all our type signatures.
(Ironically, I seem to distantly remember that many years ago, `Place::Local` *did* have an `offset`, and I removed it to simplify things. I guess I didn't realize why it was so useful... I am also not sure if this was actually used to achieve place projection on `&self` back then.)
The `offset` had type `Option<Size>`, where `None` represent "no projection was applied". This is needed because locals *can* be unsized (when they are arguments) but `Place::Local` cannot store metadata: if the offset is `None`, this refers to the entire local, so we can use the metadata of the local itself (which must be indirect); if a projection gets applied, since the local is indirect, it will turn into a `Place::Ptr`. (Note that even for indirect locals we can have `Place::Local`: when the local appears in MIR, we always start with `Place::Local`, and only check `frame.locals` later. We could eagerly normalize to `Place::Ptr` but I don't think that would actually simplify things much.)
Having done all that, we can finally properly abstract projections: we have a new `Projectable` trait that has the basic methods required for projecting, and then all projection methods are implemented for anything that implements that trait. We can even implement it for `ImmTy`! (Not that we need that, but it seems neat.) The visitor can be greatly simplified; it doesn't need its own trait any more but it can use the `Projectable` trait. We also don't need the separate `Mut` visitor any more; that was required only to reflect that projections on `PlaceTy` needed `&mut self`.
It is possible that there are some more `&mut self` that can now become `&self`... I guess we'll notice that over time.
r? `@oli-obk`
This is necessary for closure captures in 2021 edition, as they capture individual fields, not the full mentioned variables. So it may try to capture a field of an opaque (because the hidden type is known to be something with a field).
rustdoc: handle cross-crate RPITITs correctly
Filter out the internal associated types synthesized during the desugaring of RPITITs, they really shouldn't show up in the docs.
This also fixes#113929 since we're no longer invoking `is_impossible_associated_item` (renamed from `is_impossible_method`) which cannot handle them (leading to an ICE). I don't think it makes sense to try to make `is_impossible_associated_item` handle this exotic kind of associated type (CC original author `@compiler-errors).`
@ T-rustdoc reviewers, currently I'm throwing out ITIT assoc tys before cleaning assoc tys at each usage-site. I'm thinking about making `clean_middle_assoc_item` return an `Option<_>` instead and doing the check inside of it to prevent any call sites from forgetting the check for ITITs. Since I wasn't sure if you would like that approach, I didn't go through with it. Let me know what you think.
<details><summary>Explanation on why <code>is_impossible_associated_item(itit_assoc_ty)</code> leads to an ICE</summary>
Given the following code:
```rs
pub trait Trait { fn def<T>() -> impl Default {} }
impl Trait for () {}
```
The generated associated type looks something like (simplified):
```rs
type {opaque#0}<T>: Default = impl Default; // the name is actually `kw::Empty` but this is the `def_path_str` repr
```
The query `is_impossible_associated_item` goes through all predicates of the associated item – in this case `<T as Sized>` – to check if they contain any generic parameters from the (generic) associated type itself. For predicates that don't contain any *own* generics, it does further processing, part of which is instantiating the predicate with the generic arguments of the impl block (which is only correct if they truly don't contain any own generics since they wouldn't get instantiated this way leading to an ICE).
It checks if `parent_def_id(T) == assoc_ty_def_id` to get to know if `T` is owned by the assoc ty. Unfortunately this doesn't work for ITIT assoc tys. In this case, the parent of `T` is `Trait::def` (!) which is the associated function (I'm pretty sure this is very intentional) which is of course not equal to the assoc ty `Trait::{opaque#0}`.
</details>
`@rustbot` label A-cross-crate-reexports
This option guards the logic of writing long type names in files and
instead using short forms in error messages in rustc_middle/ty/error
behind a flag. The main motivation for this change is to disable this
behaviour when running ui tests.
This logic can be triggered by running tests in a directory that has a
long enough path, e.g. /my/very-long-path/where/rust-codebase/exists/
This means ui tests can fail depending on how long the path to their
file is.
Some ui tests actually rely on this behaviour for their assertions,
so for those we enable the flag manually.
Rollup of 4 pull requests
Successful merges:
- #113887 (new solver: add a separate cache for coherence)
- #113910 (Add FnPtr ty to SMIR)
- #113913 (error/E0691: include alignment in error message)
- #113914 (rustc_target: drop duplicate code)
r? `@ghost`
`@rustbot` modify labels: rollup
Still more complexity, but this allows computing exact `NaiveLayout`s
for null-optimized enums, and thus allows calls like
`transmute::<Option<&T>, &U>()` to work in generic contexts.
THis significantly complicates `NaiveLayout` logic, but is necessary to
ensure that bounds like `NonNull<T>: PointerLike` hold in generic
contexts.
Also implement exact layout computation for structs.
Querify unused trait check.
This code transitively loads information for all bodies, and from resolutions. As it does not return a value, it should be beneficial to have it as a query.
Don't translate compiler-internal bug messages
These are not very useful to be translated, as
* translators would get really weird and bad english versions to start out from,
* compiler devs have to do some work for what is supposed to be dead code and just a sanity check,
* the target audience is other compiler devs.
r? `@davidtwco`
Make it clearer that edition functions are `>=`, not `==`
r? `@Nilstrieb`
We could also perhaps derive `Ord` on `Edition` and use comparison operators.
Add the `no-builtins` attribute to functions when `no_builtins` is applied at the crate level.
**When `no_builtins` is applied at the crate level, we should add the `no-builtins` attribute to each function to ensure it takes effect in LTO.**
This is also the reason why no_builtins does not take effect in LTO as mentioned in #35540.
Now, `#![no_builtins]` should be similar to `-fno-builtin` in clang/gcc, see https://clang.godbolt.org/z/z4j6Wsod5.
Next, we should make `#![no_builtins]` participate in LTO again. That makes sense, as LTO also takes into consideration function-level instruction optimizations, such as the MachineOutliner. More importantly, when a user writes a large `#![no_builtins]` crate, they would like this crate to participate in LTO as well.
We should also add a function-level no_builtins attribute to allow users to have more control over it. This is similar to Clang's `__attribute__((no_builtin))` feature, see https://clang.godbolt.org/z/Wod6KK6eq. Before implementing this feature, maybe we should discuss whether to support more fine-grained control, such as `__attribute__((no_builtin("memcpy")))`.
Related discussions:
- #109821
- #35540
Next (a separate pull request?):
- [ ] Revert #35637
- [ ] Add a function-level `no_builtin` attribute?
Safe Transmute: Fix ICE (due to UnevaluatedConst)
This patch updates the code that looks at the `Assume` type when evaluating if transmutation is possible. An ICE was being triggered in the case that the `Assume` parameter contained an unevaluated const (in this test case, due to a function with missing parameter names).
Fixes#110892
This patch updates the code that looks at the `Assume` type when evaluating if
transmutation is possible. An ICE was being triggered in the case that the
`Assume` parameter contained an unevaluated const (in this test case, due to a
function with missing parameter names).
Fixes#110892
Use u64 for incr comp allocation offsets
Fixes https://github.com/rust-lang/rust/issues/76037
Fixes https://github.com/rust-lang/rust/issues/95780
Fixes https://github.com/rust-lang/rust/issues/111613
These issues are all reporting ICEs caused by using `u32` to store offsets to allocations in the incremental compilation cache. This PR aims to lift that limitation by changing the offset type in question to `u64`.
There are two perf runs in this PR. The first reports a regression, and the second does not. The changes are the same in both. I rebased the PR then did the second perf run because I noticed that the primary regression in it was very commonly seen in spurious regression reports.
I do not know what the perf run will report when this is merged. I would not be surprised to see regression or neutral, but the cachegrind diffs for the regression point at `try_mark_previous_green` which is a common source of inexplicable regressions and I don't think should be perturbed by this PR.
I'm not opposed to adding a regression test such as
```rust
fn main() {
println!("{}", [37; 1 << 30].len());
}
```
But that program takes 1 minute to compile and consumes 4.6 GB of memory then writes that much to disk. Is that a concerning amount of resource use for a test?
r? `@nnethercote`
Streamline size estimates (take 2)
This was merged in #113684 but then [something happened](https://github.com/rust-lang/rust/pull/113684#issuecomment-1636811985):
> There has been a bors issue that lead to the merge commit of this PR getting purged from master.
> You'll have to make a new PR to reapply it.
So this is exactly the same changes.
`@bors` r=wesleywiser
Add support for inherent projections in new solver
Not hard to support these, and it cuts out a really big chunk of failing UI tests with `--compare-mode=next-solver`
r? `@lcnr` (feel free to reassign, anyone can review this)
This means we call `MonoItem::size_estimate` (which involves a query)
less often: just once per mono item, and then once more per inline item
placement. After that we can reuse the stored value as necessary. This
means `CodegenUnit::compute_size_estimate` is cheaper.
Resurrect: rustc_target: Add alignment to indirectly-passed by-value types, correcting the alignment of byval on x86 in the process.
Same as #111551, which I [accidentally closed](https://github.com/rust-lang/rust/pull/111551#issuecomment-1571222612) :/
---
This resurrects PR #103830, which has sat idle for a while.
Beyond #103830, this also:
- fixes byval alignment for types containing vectors on Darwin (see `tests/codegen/align-byval-vector.rs`)
- fixes byval alignment for overaligned types on x86 Windows (see `tests/codegen/align-byval.rs`)
- fixes ABI for types with 128bit requested alignment on ARM64 Linux (see `tests/codegen/aarch64-struct-align-128.rs`)
r? `@nikic`
---
`@pcwalton's` original PR description is reproduced below:
Commit 88e4d2c from five years ago removed
support for alignment on indirectly-passed arguments because of problems with
the `i686-pc-windows-msvc` target. Unfortunately, the `memcpy` optimizations I
recently added to LLVM 16 depend on this to forward `memcpy`s. This commit
attempts to fix the problems with `byval` parameters on that target and now
correctly adds the `align` attribute.
The problem is summarized in [this comment] by `@eddyb.` Briefly, 32-bit x86 has
special alignment rules for `byval` parameters: for the most part, their
alignment is forced to 4. This is not well-documented anywhere but in the Clang
source. I looked at the logic in Clang `TargetInfo.cpp` and tried to replicate
it here. The relevant methods in that file are
`X86_32ABIInfo::getIndirectResult()` and
`X86_32ABIInfo::getTypeStackAlignInBytes()`. The `align` parameter attribute
for `byval` parameters in LLVM must match the platform ABI, or miscompilations
will occur. Note that this doesn't use the approach suggested by eddyb, because
I felt it was overkill to store the alignment in `on_stack` when special
handling is really only needed for 32-bit x86.
As a side effect, this should fix#80127, because it will make the `align`
parameter attribute for `byval` parameters match the platform ABI on LLVM
x86-64.
[this comment]: #80822 (comment)
Make it clearer that we're just checking for an RPITIT
Tiny nit to use `is_impl_trait_in_trait` more, to make it clearer that we're just checking whether a def-id is an RPITIT, rather than doing something meaningful with the `opt_rpitit_info`.
r? `@spastorino`
Use maybe_body_owned_by for multiple suggestions
This is a continued work from https://github.com/rust-lang/rust/pull/113567
We have several other suggestions not working for closure, this PR use `maybe_body_owned_by` to fix them and add test cases for them.
