Re-land PR #72388: Recursively expand `TokenKind::Interpolated` in `probably_equal_for_proc_macro`
PR #72388 allowed us to preserve the original `TokenStream` in more cases during proc-macro expansion, but had to be reverted due to a large number of regressions (See #72545 and #72622). These regressions fell into two categories
1. Missing handling for `Group`s with `Delimiter::None`, which are inserted during `macro_rules!` expansion (but are lost during stringification and re-parsing). A large number of these regressions were due to `syn` and `proc-macro-hack`, but several crates needed changes to their own proc-macro code.
2. Legitimate hygiene issues that were previously being masked by stringification. Some of these were relatively benign (e.g. [a compiliation error](https://github.com/paritytech/parity-scale-codec/pull/210) caused by misusing `quote_spanned!`). However, two crates had intentionally written unhygenic `macro_rules!` macros, which were able to access identifiers that were not passed as arguments (see https://github.com/rust-lang/rust/issues/72622#issuecomment-636402573).
All but one of the Crater regressions have now been fixed upstream (see https://hackmd.io/ItrXWRaSSquVwoJATPx3PQ?both). The remaining crate (which has a PR pending at https://github.com/sammhicks/face-generator/pull/1) is not on `crates.io`, and is a Yew application that seems unlikely to have any reverse dependencies.
As @petrochenkov mentioned in https://github.com/rust-lang/rust/issues/72545#issuecomment-638632434, not re-landing PR #72388 allows more crates to write unhygenic `macro_rules!` macros, which will eventually stop compiling. Since there is only one Crater regression remaining, since additional crates could write unhygenic `macro_rules!` macros in the time it takes that PR to be merged.
Currently, the def span of a funtion encompasses the entire function
signature and body. However, this is usually unnecessarily verbose - when we are
pointing at an entire function in a diagnostic, we almost always want to
point at the signature. The actual contents of the body tends to be
irrelevant to the diagnostic we are emitting, and just takes up
additional screen space.
This commit changes the `def_span` of all function items (freestanding
functions, `impl`-block methods, and `trait`-block methods) to be the
span of the signature. For example, the function
```rust
pub fn foo<T>(val: T) -> T { val }
```
now has a `def_span` corresponding to `pub fn foo<T>(val: T) -> T`
(everything before the opening curly brace).
Trait methods without a body have a `def_span` which includes the
trailing semicolon. For example:
```rust
trait Foo {
fn bar();
}```
the function definition `Foo::bar` has a `def_span` of `fn bar();`
This makes our diagnostic output much shorter, and emphasizes
information that is relevant to whatever diagnostic we are reporting.
We continue to use the full span (including the body) in a few of
places:
* MIR building uses the full span when building source scopes.
* 'Outlives suggestions' use the full span to sort the diagnostics being
emitted.
* The `#[rustc_on_unimplemented(enclosing_scope="in this scope")]`
attribute points the entire scope body.
* The 'unconditional recursion' lint uses the full span to show
additional context for the recursive call.
All of these cases work only with local items, so we don't need to
add anything extra to crate metadata.
Fixes#68430
This is a re-attempt of PR #72388, which was previously reverted due to
a large number of breakages. All of the known breakages should now be
patched upstream.
LLVM 11 started using `phi` and `select` for `fn pair_i32_bool`, which
is still valid, but harder to match than the simple instructions we were
getting before. We'll just check that the unpacked args are directly
referenced in any way, and call it good.
New zeroed slice
Add to #63291 the methods
```rust
impl<T> Box<[T]> { pub fn new_zeroed_slice(len: usize) -> Box<[MaybeUninit<T>]> {…} }
impl<T> Rc<[T]> { pub fn new_zeroed_slice(len: usize) -> Rc<[MaybeUninit<T>]> {…} }
impl<T> Arc<[T]> { pub fn new_zeroed_slice(len: usize) -> Arc<[MaybeUninit<T>]> {…} }
```
as suggested in https://github.com/rust-lang/rust/issues/63291#issuecomment-605511675 .
Also optimize `{Rc, Arc}::new_zeroed` to use `alloc_zeroed`, otherwise they are no more efficient than using `new_uninit` and zeroing the memory manually (which was the original implementation).
Don't lint if it has always inline attribute
Don't trigger the lint `trivially_copy_pass_by_ref` if it has `#[inline(always)]` attribute.
Note: I am not particularly familiar with `inline` impacts, so I implemented this the way that if only `#[inline]` attribute is here (without `always`), the lint will still trigger. Also, it will still trigger if it has `#[inline(never)]`.
Just tell me if it sounds too much conservative.
Fixes: #5876
changelog: none
Move to intra-doc links for library/core/src/alloc/{layout, global, mod}.rs
Helps with #75080. The files already contained intra-doc links, so there are only minor changes.
@rustbot modify labels: T-doc, A-intra-doc-links, T-rustdoc
Known issues:
* [`handle_alloc_error`]: Link from `core` to `alloc` could not be resolved.
* [`slice`]: slice is a primitive type, but could not be resolved; had to use [`crate::slice`] instead.
Widen understanding of prelude import
Prelude imports are exempt from wildcard import warnings. Until now only
imports of the form
```
use ...::prelude::*;
```
were considered. This change makes it so that the segment `prelude` can
show up anywhere, for instance:
```
use ...::prelude::v1::*;
```
Fixes#5917
changelog: Allow `prelude` to appear in any segment of the import path in [`wildcard_imports`]
Prelude imports are exempt from wildcard import warnings. Until now only
imports of the form
```
use ...::prelude::*;
```
were considered. This change makes it so that the segment `prelude` can
show up anywhere, for instance:
```
use ...::prelude::v1::*;
```
Fixes#5917
cargotest: fix clippy warnings
Fixes clippy::redundant_static_lifetimes and clippy::toplevel_ref_arg
I also replaced some .expect("") calls with .unwrap()s since there was no message passed by the .expect() anyway.
Missing doc examples lint improvements
Fixes#75719.
To be merged after #75718 (only the two last commits are from this PR).
Since you already reviewed #75718, I'll set you as reviewer here as well. :)
r? @jyn514
This avoids taking the slow path several thousand times in a row.
- Fallback to all traits if the traits in scope are unknown
- Use a rustdoc thread_local cache instead of a query
The set of traits implemented by a type is not stable across crates:
there could be new traits added in a new crate.
- Use DocContext instead of a thread-local
Previously, associated items would only be available for linking
directly on the `impl Trait for Type`. Now they can be used anywhere.
- Make `item` for resolve mandatory
- Refactor resolving associated items into a separate function
- Remove broken trait_item logic
- Don't skip the type namespace for associated items
- Only call `variant_field` for `TypeNS`
- Add test for associated items
- Use exhaustive matches instead of wildcards
Wildcards caused several bugs while implementing this.
