While it shares more than zero code with the SysV x86-32 ABI impl,
there is no particular reason to organize wildly different ABIs
using if-else in the same function.
Inline `FnOnce`/`FnMut`/`Fn` shims once again
This PR fixes the argument checking for `extern "rust-call"` ABI functions with a spread arg, which do no expect their arguments to be exploded from a tuple like closures do.
Secondly, it removes the hack that prevented them from being inlined. This results in more work done by the compiler, but it does end up allowing us to inline functions we didn't before.
Fixes#137901
compiler: add `ExternAbi::is_rustic_abi`
Various parts of the compiler were hand-rolling this extremely simple check that is nonetheless easy to get wrong as the compiler evolves over time. Discourage them from being so "original" again by replacing it with a single implementation on the type that represents these ABIs. This simplifies a surprising amount of code as a result.
Also fixes#132981, an ICE that emerged due to other checks being made stricter.
mir_build: Integrate "simplification" steps into match-pair-tree creation
The “simplification” step helps to prepare THIR patterns for lowering into MIR, and originally dates back to the earliest days of MIR in the compiler.
Over time, various intermediate data structures have been introduced (e.g. `MatchPair`, later renamed to `MatchPairTree`) that reduce the need for a separate simplification step, because some of the necessary simplifications can be built into the construction of those intermediate structures instead. This PR continues that process to its logical conclusion and removes the simplification step entirely, by integrating its remaining responsibilities into match-pair-tree creation: flattening “irrefutable” nodes, collecting bindings/ascriptions in flat lists, and sorting or-patterns after other subpatterns.
This has a few immediate benefits:
- We can remove `TestCase::Irrefutable`, which was not allowed to exist after simplification, and was much larger than other test-case variants.
- We can make `MatchPairTree::place` non-optional, because only irrefutable nodes could fail to have a place.
In the future, this should also help with some ideas I have for simplifying how `AscribeUserType` and `ExpandedConstant` nodes are handled, by representing them as side-data keyed by THIR pattern ID, so that they are no longer their own kinds of THIR pattern node.
Resume one waiter at once in deadlock handler
When multiple query loop errors occur in the code, only one waiter should be resumed at a time to avoid waking up multiple waiters at the same time and causing deadlock due to thread grabbing.
This fixes the UI failures in #132051
cc `@Zoxc` `@cjgillot` `@nnethercote` `@bjorn3` `@Kobzol`
Zulip discussion [here](https://rust-lang.zulipchat.com/#narrow/channel/187679-t-compiler.2Fwg-parallel-rustc/topic/Deadlocks.20and.20Rayon)
Edit: We can't reproduce these bugs with the existing test suits, so we keep them until we merge #132051
UPDATES #129912
UPDATES #120757
UPDATES #129911
Only use implied bounds hack if bevy, and use deeply normalize in implied bounds hack
Consolidates the implied bounds computation mode into a single function, which deeply normalizes, and if it's in **compat** mode (for bevy), it extracts outlives bounds from the infcx.
Previously, we were using the implied bounds compat mode in two cases:
1. During WF, if it detects `ParamSet`
2. EVERYWHERE ELSE (lol) -- e.g. borrowck, predicate entailment, etc.
While I think this is fine, and the net effect was just that we emitted fewer diagnostics, it makes me uncomfortable that all crates were using the supposed "compat" code.
Fixes#137767
Make `ptr_cast_add_auto_to_object` lint into hard error
In Rust 1.81, we added a FCW lint (including linting in dependencies) against pointer casts that add an auto trait to dyn bounds. This was part of work making casts of pointers involving trait objects stricter, and was part of the work needed to restabilize trait upcasting.
We considered just making this a hard error, but opted against it at that time due to breakage found by crater. This breakage was mostly due to the `anymap` crate which has been a persistent problem for us.
It's now a year later, and the fact that this is not yet a hard error is giving us pause about stabilizing arbitrary self types and `derive(CoercePointee)`. So let's see about making a hard error of this.
r? ghost
cc ```@adetaylor``` ```@Darksonn``` ```@BoxyUwU``` ```@RalfJung``` ```@compiler-errors``` ```@oli-obk``` ```@WaffleLapkin```
Related:
- https://github.com/rust-lang/rust/pull/135881
- https://github.com/rust-lang/rust/issues/136702
- https://github.com/rust-lang/rust/pull/136776
Tracking:
- https://github.com/rust-lang/rust/issues/127323
- https://github.com/rust-lang/rust/issues/44874
- https://github.com/rust-lang/rust/issues/123430
Make CrateItem::body() function return an option
When we initially created `CrateItem`, it would only represent items that contain a body.
That is no longer the case, for now, make this explicit by expanding the APIs to retrieve the item body.
This is related to https://github.com/rust-lang/project-stable-mir/issues/34
r? `@oli-obk`
Pretty-print `#[deprecated]` attribute in HIR.
Pretty-print `#[deprecated]` attribute in a form closer to how it might appear in Rust source code, rather than using a `Debug`-like representation.
Consider the following Rust code:
```rust
#[deprecated]
pub struct PlainDeprecated;
#[deprecated = "here's why this is deprecated"]
pub struct DirectNote;
#[deprecated(since = "1.2.3", note = "here's why this is deprecated")]
pub struct SinceAndNote;
```
Here's the previous output:
```
#[attr="Deprecation{deprecation: Deprecation{since: Unspecifiednote:
suggestion: }span: }")]
struct PlainDeprecated;
#[attr="Deprecation{deprecation: Deprecation{since: Unspecifiednote:
here's why this is deprecatedsuggestion: }span: }")]
struct DirectNote;
#[attr="Deprecation{deprecation: Deprecation{since: NonStandard(1.2.3)note:
here's why this is deprecatedsuggestion: }span: }")]
struct SinceAndNote;
```
Here's the new output:
```rust
#[deprecated]
struct PlainDeprecated;
#[deprecated = "here's why this is deprecated"]
struct DirectNote;
#[deprecated(since = "1.2.3", note = "here's why this is deprecated"]
struct SinceAndNote;
```
Also includes a test for `#[diagnostic::(..)]` attributes, though their behavior is not changed here. I already wrote the test, so I figured it probably won't hurt to have it.
Related to discussion in #137645.
r? `@jdonszelmann`
Remove unused `PpMode::needs_hir`
This method was added in #99360 to avoid an overzealous `span_delayed_bug` ICE in specific circumstances, but the only caller was subsequently removed in #136603, which presumably avoids the problem in a more principled way.
Simplify `<Postorder as Iterator>::size_hint`
The current version is sometimes malformed (cc #137919); let's see if we can get away with a loose but trivially-correct one.
Allow struct field default values to reference struct's generics
Right now, the default field value feature (https://github.com/rust-lang/rust/issues/132162) lowers anon consts whose types may reference ADT params that the const doesn't inherit.
This PR fixes this, so that these defaults can reference ADTs' generics, and sets the `generics_of` parenting up correctly.
There doesn't seem to be a good reason not to support this, since the anon const has a well-defined type from the field, and the anon const doesn't interact with the type system like generic parameter defaults do.
r? `````@boxyuwu````` or reassign
I could also make this into an error if this seems problematic (https://github.com/rust-lang/rust/compare/master...compiler-errors:rust:default-field-value-implicit-param?expand=1)...... but I'd rather make this work and register an open question on the tracking issue about validating that this is well-vetted.
Fixes#137896
Do not recover missing lifetime with random in-scope lifetime
Suppresses a ton of stray errors, since this recovery doesn't really make sense anymore now that we have a dedicated `ReError` kind.
r? oli-obk or reassign
When we initially created `CrateItem`, it would only represent items
that contain a body.
That is no longer the case, for now, make this explicit by expanding
the APIs to retrieve the item body.
This is related to https://github.com/rust-lang/project-stable-mir/issues/34
