Implement `for<>` lifetime binder for closures
This PR implements RFC 3216 ([TI](https://github.com/rust-lang/rust/issues/97362)) and allows code like the following:
```rust
let _f = for<'a, 'b> |a: &'a A, b: &'b B| -> &'b C { b.c(a) };
// ^^^^^^^^^^^--- new!
```
cc ``@Aaron1011`` ``@cjgillot``
Implement `SourceMap::is_span_accessible`
This patch adds `SourceMap::is_span_accessible` and replaces `span_to_snippet(span).is_ok()` and `span_to_snippet(span).is_err()` with it. This removes a `&str` to `String` conversion.
There are several indications that we should not ZST as a ScalarInt:
- We had two ways to have ZST valtrees, either an empty `Branch` or a `Leaf` with a ZST in it.
`ValTree::zst()` used the former, but the latter could possibly arise as well.
- Likewise, the interpreter had `Immediate::Uninit` and `Immediate::Scalar(Scalar::ZST)`.
- LLVM codegen already had to special-case ZST ScalarInt.
So instead add new ZST variants to those types that did not have other variants
which could be used for this purpose.
This makes it possible to mutably borrow different fields of the MIR
body without resorting to methods like `basic_blocks_local_decls_mut_and_var_debug_info`.
To preserve validity of control flow graph caches in the presence of
modifications, a new struct `BasicBlocks` wraps together basic blocks
and control flow graph caches.
The `BasicBlocks` dereferences to `IndexVec<BasicBlock, BasicBlockData>`.
On the other hand a mutable access requires explicit `as_mut()` call.
lints: mostly translatable diagnostics
As lints are created slightly differently than other diagnostics, intended to try make them translatable first and then look into the applicability of diagnostic structs but ended up just making most of the diagnostics in the crate translatable (which will still be useful if I do make a lot of them structs later anyway).
r? ``@compiler-errors``
Change enum->int casts to not go through MIR casts.
follow-up to https://github.com/rust-lang/rust/pull/96814
this simplifies all backends and even gives LLVM more information about the return value of `Rvalue::Discriminant`, enabling optimizations in more cases.
Rewrite dead-code pass to avoid fetching HIR.
This allows to get a more uniform handling of spans, and to simplify the grouping of diagnostics for variants and fields.
Accept `DiagnosticMessage` in `LintDiagnosticBuilder::build` so that
lints can be built with translatable diagnostic messages.
Signed-off-by: David Wood <david.wood@huawei.com>
Avoid some `&str` to `String` conversions with `MultiSpan::push_span_label`
This patch removes some`&str` to `String` conversions with `MultiSpan::push_span_label`.
Don't omit comma when suggesting wildcard arm after macro expr
* Also adds `Span::eq_ctxt` to consolidate the various usages of `span.ctxt() == other.ctxt()`
* Also fixes an unhygenic usage of spans which caused the suggestion to render weirdly when we had one arm match in a macro
* Also always suggests a comma (i.e. even after a block) if we're rendering a wildcard arm in a single-line match (looks prettier 🌹)
Fixes#94866
Fix `SourceScope` for `if let` bindings.
Fixes#97799.
I'm not sure how to test this properly, is there any way to observe the difference in behavior apart from `ui` tests? I'm worried that they would be overlooked in the case of a regression.
This commit removes the `a == b` early return, which isn't useful in
practice, and replaces it with one that helps matches with many ranges,
including char ranges.
The code is clearer and simpler without it. Note that the `a == b` early
return at the top of the function means the `a == b` test at the end of
the function could never succeed.
