Compute `is_late_bound_map` query separately from lifetime resolution
This query is actually very simple, and is only useful for functions and method. It can be computed directly by fetching the HIR, with no need to embed it within the lifetime resolution visitor.
Based on https://github.com/rust-lang/rust/pull/96296
On E0204 suggest missing type param bounds
```
error[E0204]: the trait `Copy` may not be implemented for this type
--> f42.rs:9:17
|
9 | #[derive(Debug, Copy, Clone)]
| ^^^^
10 | pub struct AABB<K>{
11 | pub loc: Vector2<K>,
| ------------------- this field does not implement `Copy`
12 | pub size: Vector2<K>
| -------------------- this field does not implement `Copy`
|
note: the `Copy` impl for `Vector2<K>` requires that `K: Debug`
--> f42.rs:11:5
|
11 | pub loc: Vector2<K>,
| ^^^^^^^^^^^^^^^^^^^
note: the `Copy` impl for `Vector2<K>` requires that `K: Debug`
--> f42.rs:12:5
|
12 | pub size: Vector2<K>
| ^^^^^^^^^^^^^^^^^^^^
= note: this error originates in the derive macro `Copy` (in Nightly builds, run with -Z macro-backtrace for more info)
help: consider restricting type parameter `K`
|
10 | pub struct AABB<K: Debug>{
| +++++++
```
Fix#89137.
take back half-baked noaliasing check in Assignment
Doing an aliasing check in `copy_op` does not make a ton of sense. We have to eventually do something in the `Assignment` statement handling instead.
Stabilize `{slice,array}::from_ref`
This PR stabilizes the following APIs as `const` functions in Rust `1.63`:
```rust
// core::array
pub const fn from_ref<T>(s: &T) -> &[T; 1];
// core::slice
pub const fn from_ref<T>(s: &T) -> &[T];
```
Note that the `mut` versions are not stabilized as unique references (`&mut _`) are [unstable in const context].
FCP: https://github.com/rust-lang/rust/issues/90206#issuecomment-1134586665
r? rust-lang/libs-api `@rustbot` label +T-libs-api -T-libs
[unstable in const context]: https://github.com/rust-lang/rust/issues/57349
Remove label/lifetime shadowing warnings
This PR removes some pre-1.0 shadowing warnings for labels and lifetimes.
The current behaviour of the compiler is to warn
* labels that shadow unrelated labels in the same function --> removed
```rust
'a: loop {}
'a: loop {} // STOP WARNING
```
* labels that shadow enclosing labels --> kept, but only if shadowing is hygienic
```rust
'a: loop {
'a: loop {} // KEEP WARNING
}
```
* labels that shadow lifetime --> removed
```rust
fn foo<'a>() {
'a: loop {} // STOP WARNING
}
```
* lifetimes that shadow labels --> removed
```rust
'a: loop {
let b = Box::new(|x: &i8| *x) as Box<dyn for <'a> Fn(&'a i8) -> i8>; // STOP WARNING
}
```
* lifetimes that shadow lifetimes --> kept
```rust
fn foo<'a>() {
let b = Box::new(|x: &i8| *x) as Box<dyn for <'a> Fn(&'a i8) -> i8>; // KEEP WARNING
}
```
Closes https://github.com/rust-lang/rust/issues/31745.
-----
From `@petrochenkov` in https://github.com/rust-lang/rust/pull/95781#issuecomment-1105199014
> I think we should remove these silly checks entirely.
> They were introduced long time ago in case some new language features appear and require this space.
> Now we have another mechanism for such language changes - editions, and if "lifetimes in expressions" or something like that needs to be introduced it could be introduced as an edition change.
> However, there was no plans to introduce anything like for years, so it's unlikely that even the edition mechanism will be necessary.
r? rust-lang/lang
Improve documentation for constructors of pinned `Box`es
Adds a cross-references between `Box::pin` and `Box::into_pin` (and other related methods, i.e. the equivalent `From` implementation, and the unstable `pin_in` method), in particular now that `into_pin` [was stabilized](https://github.com/rust-lang/rust/pull/97397). The main goal is to further improve visibility of the fact that `Box<T> -> Pin<Box<T>>` conversion exits in the first place, and that `Box::pin(x)` is – essentially – just a convenience function for `Box::into_pin(Box::new(x))`
The motivating context why I think this is important is even experienced Rust users overlooking the existence this kind of conversion, [e.g. in this thread on IRLO](https://internals.rust-lang.org/t/pre-rfc-function-variants/16732/7?u=steffahn); and also the fact that that discussion brought up that there would be a bunch of Box-construction methods "missing" such as e.g. methods with fallible allocation a la "`Box::try_pin`", and similar; while those are in fact *not* necessary, because you can use `Box::into_pin(Box::try_new(x)?)` instead.
I have *not* included explicit mention of methods (e.g. `try_new`) in the docs of stable methods (e.g. `into_pin`). (Referring to unstable API in stable API docs would be bad style IMO.) Stable examples I have in mind with the statement "constructing a (pinned) Box in a different way than with `Box::new`" are things like cloning a `Box`, or `Box::from_raw`. If/when `try_new` would get stabilized, it would become a very good concrete example use-case of `Box::into_pin` IMO.
don't use a `span_note` for ignored impls
Searching for the `derive` isn't too difficult as it's right above the field definition.
By using a span these errors are a lot more verbose than they should be, which is especially annoying as one can end up with a lot of `dead_code` warnings.
```
error[E0204]: the trait `Copy` may not be implemented for this type
--> f42.rs:9:17
|
9 | #[derive(Debug, Copy, Clone)]
| ^^^^
10 | pub struct AABB<K>{
11 | pub loc: Vector2<K>,
| ------------------- this field does not implement `Copy`
12 | pub size: Vector2<K>
| -------------------- this field does not implement `Copy`
|
note: the `Copy` impl for `Vector2<K>` requires that `K: Debug`
--> f42.rs:11:5
|
11 | pub loc: Vector2<K>,
| ^^^^^^^^^^^^^^^^^^^
note: the `Copy` impl for `Vector2<K>` requires that `K: Debug`
--> f42.rs:12:5
|
12 | pub size: Vector2<K>
| ^^^^^^^^^^^^^^^^^^^^
= note: this error originates in the derive macro `Copy` (in Nightly builds, run with -Z macro-backtrace for more info)
help: consider restricting type parameter `K`
|
10 | pub struct AABB<K: Debug>{
| +++++++
```
Fix#89137.
Lazify `SourceFile::lines`.
`SourceFile::lines` is a big part of metadata. It's stored in a compressed form
(a difference list) to save disk space. Decoding it is a big fraction of
compile time for very small crates/programs.
This commit introduces a new type `SourceFileLines` which has a `Lines`
form and a `Diffs` form. The latter is used when the metadata is first
read, and it is only decoded into the `Lines` form when line data is
actually needed. This avoids the decoding cost for many files,
especially in `std`. It's a performance win of up to 15% for tiny
crates/programs where metadata decoding is a high part of compilation
costs.
A `RefCell` is needed because the methods that access lines data (which can
trigger decoding) take `&self` rather than `&mut self`. To allow for this,
`SourceFile::lines` now takes a `FnMut` that operates on the lines slice rather
than returning the lines slice.
r? `@Mark-Simulacrum`
Revert #96682.
The change was "Show invisible delimiters (within comments) when pretty
printing". It's useful to show these delimiters, but is a breaking
change for some proc macros.
Fixes#97608.
r? ``@petrochenkov``
