Remove some suspicious cast truncations
These truncations were added a long time ago, and as best I can tell without a perf justification. And with rust-lang/rust#110410 it has become perf-neutral to not truncate anymore. We worked hard for all these bits, let's use them.
Rollup of 7 pull requests
Successful merges:
- #110038 (Erase regions when confirming transmutability candidate)
- #110341 (rustdoc: stop passing a title to `replaceState` second argument)
- #110388 (Add a message for if an overflow occurs in `core::intrinsics::is_nonoverlapping`.)
- #110404 (fix clippy::toplevel_ref_arg and ::manual_map)
- #110421 (Spelling librustdoc)
- #110423 (Spelling srcdoc)
- #110433 (Windows: map a few more error codes to ErrorKind)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Alloc `hir::Lit` in an arena to remove the destructor from `Expr`
This allows allocating `Expr`s into a dropless arena, which is useful for using length prefixed thing slices in HIR, since these can only be allocated in the dropless arena and not in a typed arena.
Permit MIR inlining without #[inline]
I noticed that there are at least a handful of portable-simd functions that have no `#[inline]` but compile to an assign + return.
I locally benchmarked inlining thresholds between 0 and 50 in increments of 5, and 50 seems to be the best. Interesting. That didn't include check builds though, ~maybe perf will have something to say about that~.
Perf has little useful to say about this. We generally regress all the check builds, as best as I can tell, due to a number of small codegen changes in a particular hot function in the compiler. Probably this is because we've nudged the inlining outcomes all over, and uses of `#[inline(always)]`/`#[inline(never)]` might need to be adjusted.
This allows allocating `Expr`s into a dropless arena, which is useful
for using length prefixed thing slices in HIR, since these can only be
allocated in the dropless arena and not in a typed arena. This is
something I'm working on.
Remove the loop in `Align::from_bytes`
Perf is almost certainly irrelevant, but might as well simplify it, since `trailing_zeros` does exactly what's needed.
Remove `TypeSuper{Foldable,Visitable}` impls for `Region`.
These traits exist so that folders/visitors can recurse into types of interest: binders, types, regions, predicates, and consts. But `Region` is non-recursive and cannot contain other types of interest, so its methods in these traits are trivial.
This commit inlines and removes those trivial methods.
r? `@compiler-errors`
Remove `remap_env_constness` in queries
This removes some of the complexities with const traits. #88119 used to be caused by this but was fixed by `param_env = param_env.without_const()`.
This allows us to get rid of the `rustc_const_eval->rustc_borrowck`
dependency edge which was delaying the compilation of borrowck.
The added utils in `rustc_middle` are small and should not affect
compile times there.
Don't `use rustc_hir as ast`(!)
It makes for confusing code.
This was introduced in a large commit in #67886 that rearranged a lot of `use` statements. I suspect it was an accident.
I suspect this macro was around before `TypeFoldable`/`TypeVisitable`
were derivable. But now it's only used for two types, `Result` and
`Option`. Removing the macro and implementing the traits for those types
by hand makes the code much simpler.
suggest lifetime for closure parameter type when mismatch
This is a draft PR, will add test cases later and be ready for review.
This PR fixes https://github.com/rust-lang/rust/issues/105675 by adding a diagnostics suggestion. Also a partial fix to https://github.com/rust-lang/rust/issues/105528.
The following code will have a compile error now:
```
fn const_if_unit(input: bool) -> impl for<'a> FnOnce(&'a ()) -> usize {
let x = |_| 1;
x
}
```
Before this PR:
```
error[E0308]: mismatched types
--> src/lib.rs:3:5
|
3 | x
| ^ one type is more general than the other
|
= note: expected trait `for<'a> FnOnce<(&'a (),)>`
found trait `FnOnce<(&(),)>`
note: this closure does not fulfill the lifetime requirements
--> src/lib.rs:2:13
|
2 | let x = |_| 1;
| ^^^
error: implementation of `FnOnce` is not general enough
--> src/lib.rs:3:5
|
3 | x
| ^ implementation of `FnOnce` is not general enough
|
= note: closure with signature `fn(&'2 ()) -> usize` must implement `FnOnce<(&'1 (),)>`, for any lifetime `'1`...
= note: ...but it actually implements `FnOnce<(&'2 (),)>`, for some specific lifetime `'2`
For more information about this error, try `rustc --explain E0308`.
error: could not compile `rust-test` due to 2 previous errors
```
After this PR:
```
error[E0308]: mismatched types
--> src/lib.rs:3:5
|
3 | x
| ^ one type is more general than the other
|
= note: expected trait `for<'a> FnOnce<(&'a (),)>`
found trait `FnOnce<(&(),)>`
note: this closure does not fulfill the lifetime requirements
--> src/lib.rs:2:13
|
2 | let x = |_| 1;
| ^^^
help: consider changing the type of the closure parameters
|
2 | let x = |_: &_| 1;
| ~~~~~~~
error: implementation of `FnOnce` is not general enough
--> src/lib.rs:3:5
|
3 | x
| ^ implementation of `FnOnce` is not general enough
|
= note: closure with signature `fn(&'2 ()) -> usize` must implement `FnOnce<(&'1 (),)>`, for any lifetime `'1`...
= note: ...but it actually implements `FnOnce<(&'2 (),)>`, for some specific lifetime `'2`
For more information about this error, try `rustc --explain E0308`.
error: could not compile `rust-test` due to 2 previous errors
```
After applying the suggestion, it compiles. The suggestion might not always be correct as the generation procedure of that suggestion is quite simple...
These traits exist so that folders/visitors can recurse into types of
interest: binders, types, regions, predicates, and consts. But `Region`
is non-recursive and cannot contain other types of interest, so its
methods in these traits are trivial.
This commit inlines and removes those trivial methods.
