Suggest to create a new `const` item if the `fn` in the array is a `const fn`
Fixes#73734. If the `fn` in the array repeat expression is a `const fn`, suggest creating a new `const` item. On nightly, suggest creating an inline `const` block. This PR also removes the `suggest_const_in_array_repeat_expressions` as it is no longer necessary.
Example:
```rust
fn main() {
// Should not compile but hint to create a new const item (stable) or an inline const block (nightly)
let strings: [String; 5] = [String::new(); 5];
println!("{:?}", strings);
}
```
Gives this error:
```
error[E0277]: the trait bound `std::string::String: std::marker::Copy` is not satisfied
--> $DIR/const-fn-in-vec.rs:3:32
|
2 | let strings: [String; 5] = [String::new(); 5];
| ^^^^^^^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `String`
|
= note: the `Copy` trait is required because the repeated element will be copied
```
With this change, this is the error message:
```
error[E0277]: the trait bound `String: Copy` is not satisfied
--> $DIR/const-fn-in-vec.rs:3:32
|
LL | let strings: [String; 5] = [String::new(); 5];
| ^^^^^^^^^^^^^^^^^^ the trait `Copy` is not implemented for `String`
|
= help: moving the function call to a new `const` item will resolve the error
```
Check the result cache before the DepGraph when ensuring queries
Split out of https://github.com/rust-lang/rust/pull/70951
Calling `ensure` on already forced queries is a common operation.
Looking at the results cache first is faster than checking the DepGraph for a green node.
On 32-bit ARM platforms, the register `r14` has the alias `lr`. When used as an output register in `asm!`, rustc canonicalizes the name to `r14`. LLVM only knows the register by the name `lr`, and rejects it. This changes rustc's LLVM code generation to output `lr` instead.
The `rustc_data_structures::sync::OnceCell` is thread-safe when building
a parallel compiler. This is unnecessary for the purposes of pattern
usefulness checking. Use `!Sync` `std::lazy::OnceCell` instead.
Rollup of 11 pull requests
Successful merges:
- #80523 (#[doc(inline)] sym_generated)
- #80920 (Visit more targets when validating attributes)
- #81720 (Updated smallvec version due to RUSTSEC-2021-0003)
- #81891 ([rustdoc-json] Make `header` a vec of modifiers, and FunctionPointer consistent)
- #81912 (Implement the precise analysis pass for lint `disjoint_capture_drop_reorder`)
- #81914 (Fixing bad suggestion for `_` in `const` type when a function #81885)
- #81919 (BTreeMap: fix internal comments)
- #81927 (Add a regression test for #32498)
- #81965 (Fix MIR pretty printer for non-local DefIds)
- #82029 (Use debug log level for developer oriented logs)
- #82056 (fix ice (#82032))
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
In the backend we may want to remove certain temporary files, but in
certain other situations these files might not be produced in the first
place. We don't exactly care about that, and the intent is really that
these files are gone after a certain point in the backend.
Here we unify the backend file removing calls to use `ensure_removed`
which will attempt to delete a file, but will not fail if it does not
exist (anymore).
The tradeoff to this approach is, of course, that we may miss instances
were we are attempting to remove files at wrong paths due to some bug –
compilation would silently succeed but the temporary files would remain
there somewhere.
Use debug log level for developer oriented logs
The information logged here is of limited general interest, while at the
same times makes it impractical to simply enable logging and share the
resulting logs due to the amount of the output produced.
Reduce log level from info to debug for developer oriented information.
For example, when building cargo, this reduces the amount of logs
generated by `RUSTC_LOG=info cargo build` from 265 MB to 79 MB.
Continuation of changes from 81350.
Fix MIR pretty printer for non-local DefIds
Tries to fix#81200 -- the reproducer in the issue is not fixed yet.
Submitting PR to get feedback.
r? oli-obk
Fixing bad suggestion for `_` in `const` type when a function #81885Closes#81885
```
error[E0121]: the type placeholder `_` is not allowed within types on item signatures
--> $DIR/typeck_type_placeholder_item_help.rs:13:22
|
LL | const TEST4: fn() -> _ = 42;
| ^
| |
| not allowed in type signatures
| help: use type parameters instead: `T`
```
Do not show the suggestion `help: use type parameters instead: T` when `fn`
Implement the precise analysis pass for lint `disjoint_capture_drop_reorder`
The precision pass for the lint prevents the lint from triggering for a variable (that was previously entirely captured by the closure) if all paths that need Drop starting at root variable have been captured by the closure.
r? `@nikomatsakis`
Updated smallvec version due to RUSTSEC-2021-0003
Hi.
Updated Cargo.toml's for smallvec due to RUSTSEC-2021-0003 and Cargo.toml in separate commit.
Affected function `SmallVec::insert_many` looks like don't was used directly in rust, but can be somewhere in deps.
There should be some mechanism to not to do this kind of things manually, like dependabot. Actually, dependabot supports rust and can check security articles (at least that noted in description).
Visit more targets when validating attributes
This begins to address #80048, allowing for additional validation of attributes.
There are more refactorings that can be done, though I think they should be tackled in additional PRs:
* ICE when a builtin attribute is encountered that is not checked
* Move some of the attr checking done `ast_validation` into `rustc_passes`
* note that this requires a bit of additional refactoring, especially of extern items which currently parse attributes (and thus are a part of the AST) but do not possess attributes in their HIR representation.
* Rename `Target` to `AttributeTarget`
* Refactor attribute validation completely to go through `Visitor::visit_attribute`.
* This would require at a minimum passing `Target` into this method which might be too big of a refactoring to be worth it.
* It's also likely not possible to do all the validation this way as some validation requires knowing what other attributes a target has.
r? `@davidtwco`
#[doc(inline)] sym_generated
Manually doc-inlines `rustc_span::sym_generated` into `sym`.
Previously the docs would not get inlined, causing the symbols to be undocumented as `sym_generated` is private.
r? `@jyn514`
This is a pure refactoring split out from #80689.
It represents the most invasive part of that PR, requiring changes in
every caller of `parse_outer_attributes`
In order to eagerly expand `#[cfg]` attributes while preserving the
original `TokenStream`, we need to know the range of tokens that
corresponds to every attribute target. This is accomplished by making
`parse_outer_attributes` return an opaque `AttrWrapper` struct. An
`AttrWrapper` must be converted to a plain `AttrVec` by passing it to
`collect_tokens_trailing_token`. This makes it difficult to accidentally
construct an AST node with attributes without calling `collect_tokens_trailing_token`,
since AST nodes store an `AttrVec`, not an `AttrWrapper`.
As a result, we now call `collect_tokens_trailing_token` for attribute
targets which only support inert attributes, such as generic arguments
and struct fields. Currently, the constructed `LazyTokenStream` is
simply discarded. Future PRs will record the token range corresponding
to the attribute target, allowing those tokens to be removed from an
enclosing `collect_tokens_trailing_token` call if necessary.
