Prevent where < ident > from parsing.
In order to be forward compatible with `where<'a>` syntax for higher
rank parameters, prevent potential conflicts with UFCS from parsing
correctly for the near term.
Allow legacy custom derive authors to disable warnings in downstream crates
This PR allows legacy custom derive authors to use a pre-deprecated method `registry.register_custom_derive()` instead of `registry.register_syntax_extension()` to avoid downstream deprecation warnings.
r? @nrc
Refactor global paths
This PR removes the field `global: bool` from `ast::Path` and `hir::Path`, instead representing a global path `::foo::bar` as `{{root}}::foo::bar`, where `{{root}}` is a virtual keyword `keywords::CrateRoot`.
Also, fixes#38016.
r? @nrc
Don't perform span mangling when building field/tup access nodes
There are no guarantees that the two spans used to create the new one
come from the same place or are even valid.
Fixes#36081.
In order to be forward compatible with `where<'a>` syntax for higher
rank parameters, prevent potential conflicts with UFCS from parsing
correctly for the near term.
annotate stricter lifetimes on LateLintPass methods to allow them to forward to a Visitor
this unblocks clippy (rustup blocked after #37918)
clippy has lots of lints that internally call an `intravisit::Visitor`, but the current lifetimes on `LateLintPass` methods conflicted with the required lifetimes (there was no connection between the HIR elements and the `TyCtxt`)
r? @Manishearth
Add new #[target_feature = "..."] attribute.
This commit adds a new attribute that instructs the compiler to emit
target specific code for a single function. For example, the following
function is permitted to use instructions that are part of SSE 4.2:
#[target_feature = "+sse4.2"]
fn foo() { ... }
In particular, use of this attribute does not require setting the
-C target-feature or -C target-cpu options on rustc.
This attribute does not have any protections built into it. For example,
nothing stops one from calling the above `foo` function on hosts without
SSE 4.2 support. Doing so may result in a SIGILL.
I've also expanded the x86 target feature whitelist.
This commit adds a new attribute that instructs the compiler to emit
target specific code for a single function. For example, the following
function is permitted to use instructions that are part of SSE 4.2:
#[target_feature = "+sse4.2"]
fn foo() { ... }
In particular, use of this attribute does not require setting the
-C target-feature or -C target-cpu options on rustc.
This attribute does not have any protections built into it. For example,
nothing stops one from calling the above `foo` function on hosts without
SSE 4.2 support. Doing so may result in a SIGILL.
This commit also expands the target feature whitelist to include lzcnt,
popcnt and sse4a. Namely, lzcnt and popcnt have their own CPUID bits,
but were introduced with SSE4.
Show multiline spans in full if short enough
When dealing with multiline spans that span few lines, show the complete span instead of restricting to the first character of the first line.
For example, instead of:
```
% ./rustc file2.rs
error[E0277]: the trait bound `{integer}: std::ops::Add<()>` is not satisfied
--> file2.rs:13:9
|
13 | foo(1 + bar(x,
| ^ trait `{integer}: std::ops::Add<()>` not satisfied
|
```
show
```
% ./rustc file2.rs
error[E0277]: the trait bound `{integer}: std::ops::Add<()>` is not satisfied
--> file2.rs:13:9
|
13 | foo(1 + bar(x,
| ________^ starting here...
14 | | y),
| |_____________^ ...ending here: trait `{integer}: std::ops::Add<()>` not satisfied
|
```
The [proposal in internals](https://internals.rust-lang.org/t/proposal-for-multiline-span-comments/4242/6) outlines the reasoning behind this.
Support `?Sized` in where clauses
Implemented as described in https://github.com/rust-lang/rust/issues/20503#issuecomment-258677026 - `?Trait` bounds are moved on type parameter definitions when possible, reported as errors otherwise.
(It'd be nice to unify bounds and where clauses in HIR, but this is mostly blocked by rustdoc now - it needs to render bounds in pleasant way and the best way to do it so far is to mirror what was written in source code.)
Fixes https://github.com/rust-lang/rust/issues/20503
r? @nikomatsakis