`Deref`/`DerefMut` can be useful, but they can also obfuscate. I don't
think they're worth it for `RegionConstraintCollector`. They're also not
present on the similar types `OpaqueTypeTable` and `TypeVariableTable`.
`LeakCheck` can own `mini_graph` and `rcc` instead of holding references
to them. This requires inlining `assign_scc_value` to avoid a borrowck
error, but that's fine because it has a single call site.
It's a weird method, and used weirdly:
- It's on `RegionConstraintCollector` but operates on
`RegionConstraintStorage`. So at both call sites we create a temporary
`RegionConstraintCollector`, using `with_log`, to call it.
- It `take`s just two of the six fields in `RegionConstraintStorage`.
At one of the two call sites we unnecessarily clone the entire
`RegionConstraintStorage` just to take those two fields.
This commit just inlines and removes it. We no longer need to `take` the
two fields, we can just use them directly.
`OutlivesEnvironment::new` can call `OutlivesEnvironment::with_bounds`
with an empty `extra_bounds`. And once that's done,
`OutlivesEnvironmentBuilder` has a single use and can be inlined and
removed into `OutlivesEnvironment::with_bounds`.
Remove `CombineFields`
This conflicts with #131263, but if this one lands first then perhaps #131263 could then go ahead and remove all the branching on solver in `TypeRelating`. We could perhaps then rename `TypeRelating` to `OldSolverRelating` or something, idk.
r? lcnr
`FixupError` is isomorphic with `TyOrConstInferVar`, so this commit
changes it to just be a wrapper around `TyOrConstInferVar`.
Also, move the `Display` impl for `FixupError` next to `FixupError`.
Three of the modules don't need to be `pub`, and then
`warn(unreachable_pub)` identifies a bunch more things that also
shouldn't be `pub`, plus a couple of things that are unused.
Stabilize the `map`/`value` methods on `ControlFlow`
And fix the stability attribute on the `pub use` in `core::ops`.
libs-api in https://github.com/rust-lang/rust/issues/75744#issuecomment-2231214910 seemed reasonably happy with naming for these, so let's try for an FCP.
Summary:
```rust
impl<B, C> ControlFlow<B, C> {
pub fn break_value(self) -> Option<B>;
pub fn map_break<T>(self, f: impl FnOnce(B) -> T) -> ControlFlow<T, C>;
pub fn continue_value(self) -> Option<C>;
pub fn map_continue<T>(self, f: impl FnOnce(C) -> T) -> ControlFlow<B, T>;
}
```
Resolves#75744
``@rustbot`` label +needs-fcp +t-libs-api -t-libs
---
Aside, in case it keeps someone else from going down the same dead end: I looked at the `{break,continue}_value` methods and tried to make them `const` as part of this, but that's disallowed because of not having `const Drop`, so put it back to not even unstably-const.
Most of the code in these two modules is duplicated in the other module.
This commit eliminates the duplication by replacing them with a new
module `lattice_op`. The new `LatticeOpKind` enum is used to distinguish
between glb and lub in the few places where the behaviour differs.
add caching to most type folders, rm region uniquification
Fixes the new minimization of the hang in nalgebra and nalgebra itself :3
this is a bit iffy, especially the cache in `TypeRelating`. I believe all the caches are correct, but it definitely adds some non-local complexity in places. The first commit removes region uniquification, reintroducing the ICE from https://github.com/rust-lang/trait-system-refactor-initiative/issues/27. This does not affect coherence and I would like to fix this by introducing OR-region constraints
r? `@compiler-errors`
Remove `#[macro_use] extern crate tracing`, round 4
Because explicit importing of macros via use items is nicer (more standard and readable) than implicit importing via #[macro_use]. Continuing the work from #124511, #124914, and #125434. After this PR no `rustc_*` crates use `#[macro_use] extern crate tracing` except for `rustc_codegen_gcc` which is a special case and I will do separately.
r? ```@jieyouxu```
Given `trait Any: 'static` and a `struct` with a `Box<dyn Any + 'a>` field, point at the `'static` bound in `Any` to explain why `'a: 'static`.
```
error[E0478]: lifetime bound not satisfied
--> f202.rs:2:12
|
2 | value: Box<dyn std::any::Any + 'a>,
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
note: lifetime parameter instantiated with the lifetime `'a` as defined here
--> f202.rs:1:14
|
1 | struct Hello<'a> {
| ^^
note: but lifetime parameter must outlive the static lifetime
--> /home/gh-estebank/rust/library/core/src/any.rs:113:16
|
113 | pub trait Any: 'static {
| ^^^^^^^
```
Partially address #33652.
Shrink `TyKind::FnPtr`.
By splitting the `FnSig` within `TyKind::FnPtr` into `FnSigTys` and `FnHeader`, which can be packed more efficiently. This reduces the size of the hot `TyKind` type from 32 bytes to 24 bytes on 64-bit platforms. This reduces peak memory usage by a few percent on some benchmarks. It also reduces cache misses and page faults similarly, though this doesn't translate to clear cycles or wall-time improvements on CI.
r? `@compiler-errors`
By splitting the `FnSig` within `TyKind::FnPtr` into `FnSigTys` and
`FnHeader`, which can be packed more efficiently. This reduces the size
of the hot `TyKind` type from 32 bytes to 24 bytes on 64-bit platforms.
This reduces peak memory usage by a few percent on some benchmarks. It
also reduces cache misses and page faults similarly, though this doesn't
translate to clear cycles or wall-time improvements on CI.
Remove unnecessary impl sorting in queries and metadata
Removes unnecessary impl sorting because queries already return their keys in HIR definition order: https://github.com/rust-lang/rust/issues/120371#issuecomment-1926422838
r? `@cjgillot` or `@lcnr` -- unless I totally misunderstood what was being asked for here? 😆fixes#120371
Represent type-level consts with new-and-improved `hir::ConstArg`
### Summary
This is a step toward `min_generic_const_exprs`. We now represent all const
generic arguments using an enum that differentiates between const *paths*
(temporarily just bare const params) and arbitrary anon consts that may perform
computations. This will enable us to cleanly implement the `min_generic_const_args`
plan of allowing the use of generics in paths used as const args, while
disallowing their use in arbitrary anon consts. Here is a summary of the salient
aspects of this change:
- Add `current_def_id_parent` to `LoweringContext`
This is needed to track anon const parents properly once we implement
`ConstArgKind::Path` (which requires moving anon const def-creation
outside of `DefCollector`).
- Create `hir::ConstArgKind` enum with `Path` and `Anon` variants. Use it in the
existing `hir::ConstArg` struct, replacing the previous `hir::AnonConst` field.
- Use `ConstArg` for all instances of const args. Specifically, use it instead
of `AnonConst` for assoc item constraints, array lengths, and const param
defaults.
- Some `ast::AnonConst`s now have their `DefId`s created in
rustc_ast_lowering rather than `DefCollector`. This is because in some
cases they will end up becoming a `ConstArgKind::Path` instead, which
has no `DefId`. We have to solve this in a hacky way where we guess
whether the `AnonConst` could end up as a path const since we can't
know for sure until after name resolution (`N` could refer to a free
const or a nullary struct). If it has no chance as being a const
param, then we create a `DefId` in `DefCollector` -- otherwise we
decide during ast_lowering. This will have to be updated once all path
consts use `ConstArgKind::Path`.
- We explicitly use `ConstArgHasType` for array lengths, rather than
implicitly relying on anon const type feeding -- this is due to the
addition of `ConstArgKind::Path`.
- Some tests have their outputs changed, but the changes are for the
most part minor (including removing duplicate or almost-duplicate
errors). One test now ICEs, but it is for an incomplete, unstable
feature and is now tracked at https://github.com/rust-lang/rust/issues/127009.
### Followup items post-merge
- Use `ConstArgKind::Path` for all const paths, not just const params.
- Fix (no github dont close this issue) #127009
- If a path in generic args doesn't resolve as a type, try to resolve as a const
instead (do this in rustc_resolve). Then remove the special-casing from
`rustc_ast_lowering`, so that all params will automatically be lowered as
`ConstArgKind::Path`.
- (?) Consider making `const_evaluatable_unchecked` a hard error, or at least
trying it in crater
r? `@BoxyUwU`
Suggest using precise capturing for hidden type that captures region
Adjusts the "add `+ '_`" suggestion for opaques to instead suggest adding or reusing the `+ use<>` in the opaque.
r? oli-obk or please re-roll if you're busy!
Make `push_outlives_components` into a `TypeVisitor`
This involves removing the `visited: &mut SsoHashSet<GenericArg<'tcx>>` that is being passed around the `VerifyBoundCx`. The fact that we were using it when decomposing different type tests seems sketchy, so I don't think, though it may technically result in us registering more redundant outlives components 🤷
I did end up deleting some of the comments that referred back to RFC 1214 during this refactor. I can add them back if you think they were useful.
r? lcnr
Uplift elaboration into `rustc_type_ir`
Allows us to deduplicate and consolidate elaboration (including these stupid elaboration duplicate fns i added for pretty printing like 3 years ago) so I'm pretty hyped about this change :3
r? lcnr
