Note when a a move/borrow error is caused by a deref coercion
Fixes#73268
When a deref coercion occurs, we may end up with a move error if the
base value has been partially moved out of. However, we do not indicate
anywhere that a deref coercion is occuring, resulting in an error
message with a confusing span.
This PR adds an explicit note to move errors when a deref coercion is
involved. We mention the name of the type that the deref-coercion
resolved to, as well as the `Deref::Target` associated type being used.
Detect overflow in proc_macro_server subspan
* Detect overflow in proc_macro_server subspan
* Add tests for overflow in Vec::drain
* Add tests for overflow in String / VecDeque operations using ranges
A significant amount of intrinsics do not actually need backend-specific
behaviors to be implemented, instead relying on methods already in
rustc_codegen_ssa. So, extract those methods out to rustc_codegen_ssa,
so that each backend doesn't need to reimplement the same code.
* Change error message for type param in a const expression when using
min_const_generics
* Change ParamInNonTrivialAnonConst to contain an extra bool used for
distinguishing whether the passed-in symbol is a type or a value.
use sort_unstable to sort primitive types
It's not important to retain original order if we have &[1, 1, 2, 3] for example.
clippy::stable_sort_primitive
More structured suggestions for boxed trait objects instead of impl Trait on non-coerceable tail expressions
When encountering a `match` or `if` as a tail expression where the
different arms do not have the same type *and* the return type of that
`fn` is an `impl Trait`, check whether those arms can implement `Trait`
and if so, suggest using boxed trait objects.
Use structured suggestion for `impl T` to `Box<dyn T>`.
Fix https://github.com/rust-lang/rust/issues/69107
This commit improves the diagnostic when a type parameter is expected
and a closure is found, noting that each closure has a distinct type and
therefore could not always match the caller-chosen type of the
parameter.
Signed-off-by: David Wood <david@davidtw.co>
Auto-generate lint documentation.
This adds a tool which will generate the lint documentation in the rustc book automatically. This is motivated by keeping the documentation up-to-date, and consistently formatted. It also ensures the examples are correct and that they actually generate the expected lint. The lint groups table is also auto-generated. See https://github.com/rust-lang/compiler-team/issues/349 for the original proposal.
An outline of how this works:
- The `declare_lint!` macro now accepts a doc comment where the documentation is written. This is inspired by how clippy works.
- A new tool `src/tools/lint-docs` scrapes the documentation and adds it to the rustc book during the build.
- It runs each example and verifies its output and embeds the output in the book.
- It does a few formatting checks.
- It verifies that every lint is documented.
- Groups are collected from `rustc -W help`.
I updated the documentation for all the missing lints. I have also added an "Explanation" section to each lint providing a reason for the lint and suggestions on how to resolve it.
This can lead towards a future enhancement of possibly showing these docs via the `--explain` flag to make them easily accessible and discoverable.
suggest `where T: Foo` for the first bound on a trait, then suggest
`, T: Foo` when the suggested bound would add to an existing set of
`where` clauses. `where T: Foo` may be the first bound if `T` has a
default, because we'd rather suggest
```
trait A<T=()> where T: Copy
```
than
```
trait A<T: Copy=()>
```
for legibility reasons.
allow concrete self types in consts
This is quite a bad hack to fix#75486. There might be a better way to check if the self type depends on generic parameters, but I wasn't able to come up with one.
r? `@varkor` cc `@petrochenkov`
inliner: Emit storage markers for introduced arg temporaries
When introducing argument temporaries during inlining, emit storage
marker statements just before the assignment and in the beginning of
the return block.
This ensures that such temporaries will not be considered live across
yield points after inlining inside a generator.
Fixes#71793.
Don't query stability data when `staged_api` is off
This data only needs to be encoded when `#![feature(staged_api)]` or `-Zforce-unstable-if-unmarked` is on. Running these queries takes measurable time on large crates with many items, so skip it when the unstable flags have not been enabled.
Fixing memory exhaustion when formatting short code suggestion
Details can be found in issue #76597. This PR replaces substractions with `saturating_sub`'s to avoid usize wrapping leading to memory exhaustion when formatting short suggestion messages.
Properly encode spans with a dummy location and non-root `SyntaxContext`
Previously, we would throw away the `SyntaxContext` of any span with a
dummy location during metadata encoding. This commit makes metadata Span
encoding consistent with incr-cache Span encoding - an 'invalid span'
tag is only used when it doesn't lose any information.
