Make sure pdbs are copied along with exe and dlls when bootstrapping
This makes it easier to find the pdbs when wanting to debug the compiler on Windows.
Replace if-let and while-let with `if let` and `while let`
This pull request replaces if-let and while-let with `if let` and `while let`.
closes https://github.com/rust-lang/rust/issues/82205
const_generics: Dont evaluate array length const when handling yet another error
Same ICE as #82009 except triggered by a different error.
cc ``@lcnr``
r? ``@varkor``
Ensure valid TraitRefs are created for GATs
This fixes `ProjectionTy::trait_ref` to use the correct substs. Places that need all of the substs have been updated to not use `trait_ref`.
r? ````@jackh726````
[libtest] Run the test synchronously when hitting thread limit
libtest currently panics if it hits the thread limit. This often results in spurious test failures (<code>thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: Os { code: 11, kind: WouldBlock, message: "Resource temporarily unavailable" }'</code> ... `error: test failed, to rerun pass '--lib'`). This PR makes it continue to run the test synchronously if it runs out of threads.
Closes#78165.
``@rustbot`` label: A-libtest T-libs
It's not possible to check if removing a semicolon fixes the type error
when checking match arms and one or both of the last arm's and the
current arm's return types are imported "opaque" types. In these cases
we don't generate a "consider removing semicolon" suggestions.
Fixes#81839
Precompute ancestors when checking privacy
Precompute ancestors of the old error node set so that check for private
types and traits in public interfaces can in constant time determine if
the current item has any descendants in the old error set.
This removes disparity in compilation time between public and private type
aliases reported in #50614 (from 30 s to 5 s, in an example making extensive use
of private type aliases).
No functional changes intended.
Crate root is sufficiently different from `mod` items, at least at syntactic level.
Also remove customization point for "`mod` item or crate root" from AST visitors.
remove useless ?s (clippy::needless_question_marks)
Example code:
```rust
fn opts() -> Option<String> {
let s: Option<String> = Some(String::new());
Some(s?) // this can just be "s"
}
```
make `suggest_setup` help messages better
When I first built the compiler and didn't create a `config.toml.example`, the following was emitted:
```
help: consider running `x.py setup` or copying `config.toml.example`
```
I ran `x.py setup` but got an error so in this PR I made the help messages a little clearer.
Use !Sync std::lazy::OnceCell in usefulness checking
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.
Add diagnostics for specific cases for const/type mismatch err
For now, this adds at least more information so better diagnostics can be emitted for const mismatch errors.
I'm not sure what exactly we want to emit, so I've left notes there temporarily, also to see if this is the right approach
r? ```@lcnr```
cc: ```@estebank```
Implement RFC 2580: Pointer metadata & VTable
RFC: https://github.com/rust-lang/rfcs/pull/2580
~~Before merging this PR:~~
* [x] Wait for the end of the RFC’s [FCP to merge](https://github.com/rust-lang/rfcs/pull/2580#issuecomment-759145278).
* [x] Open a tracking issue: https://github.com/rust-lang/rust/issues/81513
* [x] Update `#[unstable]` attributes in the PR with the tracking issue number
----
This PR extends the language with a new lang item for the `Pointee` trait which is special-cased in trait resolution to implement it for all types. Even in generic contexts, parameters can be assumed to implement it without a corresponding bound.
For this I mostly imitated what the compiler was already doing for the `DiscriminantKind` trait. I’m very unfamiliar with compiler internals, so careful review is appreciated.
This PR also extends the standard library with new unstable APIs in `core::ptr` and `std::ptr`:
```rust
pub trait Pointee {
/// One of `()`, `usize`, or `DynMetadata<dyn SomeTrait>`
type Metadata: Copy + Send + Sync + Ord + Hash + Unpin;
}
pub trait Thin = Pointee<Metadata = ()>;
pub const fn metadata<T: ?Sized>(ptr: *const T) -> <T as Pointee>::Metadata {}
pub const fn from_raw_parts<T: ?Sized>(*const (), <T as Pointee>::Metadata) -> *const T {}
pub const fn from_raw_parts_mut<T: ?Sized>(*mut (),<T as Pointee>::Metadata) -> *mut T {}
impl<T: ?Sized> NonNull<T> {
pub const fn from_raw_parts(NonNull<()>, <T as Pointee>::Metadata) -> NonNull<T> {}
/// Convenience for `(ptr.cast(), metadata(ptr))`
pub const fn to_raw_parts(self) -> (NonNull<()>, <T as Pointee>::Metadata) {}
}
impl<T: ?Sized> *const T {
pub const fn to_raw_parts(self) -> (*const (), <T as Pointee>::Metadata) {}
}
impl<T: ?Sized> *mut T {
pub const fn to_raw_parts(self) -> (*mut (), <T as Pointee>::Metadata) {}
}
/// `<dyn SomeTrait as Pointee>::Metadata == DynMetadata<dyn SomeTrait>`
pub struct DynMetadata<Dyn: ?Sized> {
// Private pointer to vtable
}
impl<Dyn: ?Sized> DynMetadata<Dyn> {
pub fn size_of(self) -> usize {}
pub fn align_of(self) -> usize {}
pub fn layout(self) -> crate::alloc::Layout {}
}
unsafe impl<Dyn: ?Sized> Send for DynMetadata<Dyn> {}
unsafe impl<Dyn: ?Sized> Sync for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> Debug for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> Unpin for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> Copy for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> Clone for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> Eq for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> PartialEq for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> Ord for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> PartialOrd for DynMetadata<Dyn> {}
impl<Dyn: ?Sized> Hash for DynMetadata<Dyn> {}
```
API differences from the RFC, in areas noted as unresolved questions in the RFC:
* Module-level functions instead of associated `from_raw_parts` functions on `*const T` and `*mut T`, following the precedent of `null`, `slice_from_raw_parts`, etc.
* Added `to_raw_parts`
An attempt to compute HIR stats for crates with nested foreign items results in an ICE.
```
fn main() {
extern "C" { fn f(); }
}
```
```
thread 'rustc' panicked at 'visit_nested_xxx must be manually implemented in this visitor'
```
Provide required implementation of visitor method.
When building rustc with `-Codegen-units=1` this inline hint ensures
that obtaining already initialized head constructor does not involve
a function call overhead and reduces the instruction count in
match-stress-enum-check full benchmark from 11.9G to 9.8G.
It shouldn't have significant impact on the currently default
configuration where it reflects existing inlining decisions.
Implement reborrow for closure captures
The strategy for captures is detailed here with examples: https://hackmd.io/PzxYMPY4RF-B9iH9uj9GTA
Key points:
- We only need to reborrow a capture in case of move closures.
- If we mutate something via a `&mut` we store it as a `MutBorrow`/`UniqueMuBorrow` of the path containing the `&mut`,
- Similarly, if it's read via `&` ref we just store it as a `ImmBorrow` of the path containing the `&` ref.
- If a path doesn't deref a `&mut`, `&`, then that path is captured by Move.
- If the use of a path results in a move when the closure is called, then that path is truncated before any deref and the truncated path is moved into the closure.
- In the case of non-move closure if a use of a path results in a move, then the path is truncated before any deref and the truncated path is moved into the closure.
Note that the implementation differs a bit from the document to allow for truncated path to be used in the ClosureKind analysis that happens as part of the first capture analysis pass.
Closes: https://github.com/rust-lang/project-rfc-2229/issues/31
r? ````@nikomatsakis````
Placeholder lifetime error cleanup
- Remove note of trait definition
- Avoid repeating the same self type
- Use original region names when possible
- Use this error kind more often
- Print closure signatures when they are suppose to implement `Fn*` traits
Works towards #57374
r? ```@nikomatsakis```
Fix debug information for function arguments of type &str or slice.
Issue details:
When lowering MIR to LLVM IR, the compiler decomposes every &str and slice argument into a data pointer and a usize. Then, the original argument is reconstructed from the pointer and the usize arguments in the body of the function that owns it. Since the original argument is declared in the body of a function, it should be marked as a LocalVariable instead of an ArgumentVairable. This confusion causes MSVC debuggers unable to visualize &str and slice arguments correctly. (See https://github.com/rust-lang/rust/issues/81894 for more details).
Fix details:
Making sure that the debug variable for every &str and slice argument is marked as LocalVariable instead of ArgumentVariable in computing_per_local_var_debug_info. This change has been verified on VS Code debugger, VS debugger, WinDbg and LLDB.
Fix SourceMap::start_point
`start_point` needs to return the *first* character's span, but it would
previously call `find_width_of_character_at_span` which returns the span
of the *last* character. The implementation is now fixed.
Other changes:
- Docs for start_point, end_point, find_width_of_character_at_span
updated
- Minor simplification in find_width_of_character_at_span code
Fixes#81800
Add a `Result::into_ok_or_err` method to extract a `T` from `Result<T, T>`
When updating code to handle the semi-recent deprecation of `compare_and_swap` in favor of `compare_exchange`, which returns `Result<T, T>`, I wanted this. I've also wanted it with code using `slice::binary_search` before.
The name (and perhaps the documentation) is the hardest part here, but this name seems consistent with the other Result methods, and equivalently memorable.
I'm pretty sure I am going want this for #73125 and it seems like an
omission that would be in any case good to remedy.
It's a shame we don't have competent token pasting and case mangling
for use in macro_rules!.
Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>