Some papercuts on error::Error
Renames the chain method, since I chain could mean anything and doesn't refer to a chain of sources (cc #58520) (and adds a comment explaining why sources is not a provided method on Error). Renames arguments to the request method from `req` to `demand` since the type is `Demand` rather than Request or Requisition.
r? ``@yaahc``
Add mention of `BufReader` in `Read::bytes` docs
There is a general paragraph about `BufRead` in the `Read` trait's docs, however using `bytes` without `BufRead` *always* has a large impact, due to reads of size 1.
`@rustbot` label +A-docs
Add standard C error function aliases to last_os_error
This aids the discoverability of `io::Error::last_os_error()` by linking to commonly used error number functions from C/C++.
I've seen a few people not realize this exists, so hopefully this helps draw attention to the API to encourage using it over integer error codes.
Box::from(slice): Clarify that contents are copied
A colleague mentioned that they interpreted the old text
as saying that only the pointer and the length are copied.
Add a clause so it is more clear that the pointed to contents
are also copied.
Add GDB/LLDB pretty-printers for NonZero types
Add GDB/LLDB pretty-printers for `NonZero` types.
These pretty-printers were originally implemented for IntelliJ Rust by ```@Kobzol``` in https://github.com/intellij-rust/intellij-rust/pull/5270.
Part of #29392.
std::io: migrate ReadBuf to BorrowBuf/BorrowCursor
This PR replaces `ReadBuf` (used by the `Read::read_buf` family of methods) with `BorrowBuf` and `BorrowCursor`.
The general idea is to split `ReadBuf` because its API is large and confusing. `BorrowBuf` represents a borrowed buffer which is mostly read-only and (other than for construction) deals only with filled vs unfilled segments. a `BorrowCursor` is a mostly write-only view of the unfilled part of a `BorrowBuf` which distinguishes between initialized and uninitialized segments. For `Read::read_buf`, the caller would create a `BorrowBuf`, then pass a `BorrowCursor` to `read_buf`.
In addition to the major API split, I've made the following smaller changes:
* Removed some methods entirely from the API (mostly the functionality can be replicated with two calls rather than a single one)
* Unified naming, e.g., by replacing initialized with init and assume_init with set_init
* Added an easy way to get the number of bytes written to a cursor (`written` method)
As well as simplifying the API (IMO), this approach has the following advantages:
* Since we pass the cursor by value, we remove the 'unsoundness footgun' where a malicious `read_buf` could swap out the `ReadBuf`.
* Since `read_buf` cannot write into the filled part of the buffer, we prevent the filled part shrinking or changing which could cause underflow for the caller or unexpected behaviour.
## Outline
```rust
pub struct BorrowBuf<'a>
impl Debug for BorrowBuf<'_>
impl<'a> From<&'a mut [u8]> for BorrowBuf<'a>
impl<'a> From<&'a mut [MaybeUninit<u8>]> for BorrowBuf<'a>
impl<'a> BorrowBuf<'a> {
pub fn capacity(&self) -> usize
pub fn len(&self) -> usize
pub fn init_len(&self) -> usize
pub fn filled(&self) -> &[u8]
pub fn unfilled<'this>(&'this mut self) -> BorrowCursor<'this, 'a>
pub fn clear(&mut self) -> &mut Self
pub unsafe fn set_init(&mut self, n: usize) -> &mut Self
}
pub struct BorrowCursor<'buf, 'data>
impl<'buf, 'data> BorrowCursor<'buf, 'data> {
pub fn clone<'this>(&'this mut self) -> BorrowCursor<'this, 'data>
pub fn capacity(&self) -> usize
pub fn written(&self) -> usize
pub fn init_ref(&self) -> &[u8]
pub fn init_mut(&mut self) -> &mut [u8]
pub fn uninit_mut(&mut self) -> &mut [MaybeUninit<u8>]
pub unsafe fn as_mut(&mut self) -> &mut [MaybeUninit<u8>]
pub unsafe fn advance(&mut self, n: usize) -> &mut Self
pub fn ensure_init(&mut self) -> &mut Self
pub unsafe fn set_init(&mut self, n: usize) -> &mut Self
pub fn append(&mut self, buf: &[u8])
}
```
## TODO
* ~~Migrate non-unix libs and tests~~
* ~~Naming~~
* ~~`BorrowBuf` or `BorrowedBuf` or `SliceBuf`? (We might want an owned equivalent for the async IO traits)~~
* ~~Should we rename the `readbuf` module? We might keep the name indicate it includes both the buf and cursor variations and someday the owned version too. Or we could change it. It is not publicly exposed, so it is not that important~~.
* ~~`read_buf` method: we read into the cursor now, so the `_buf` suffix is a bit weird.~~
* ~~Documentation~~
* Tests are incomplete (I adjusted existing tests, but did not add new ones).
cc https://github.com/rust-lang/rust/issues/78485, https://github.com/rust-lang/rust/issues/94741
supersedes: https://github.com/rust-lang/rust/pull/95770, https://github.com/rust-lang/rust/pull/93359fixes#93305
Move EH personality functions to std
These were previously in the panic_unwind crate with dummy stubs in the
panic_abort crate. However it turns out that this is insufficient: we
still need a proper personality function even with -C panic=abort to
handle the following cases:
1) `extern "C-unwind"` still needs to catch foreign exceptions with -C
panic=abort to turn them into aborts. This requires landing pads and a
personality function.
2) ARM EHABI uses the personality function when creating backtraces.
The dummy personality function in panic_abort was causing backtrace
generation to get stuck in a loop since the personality function is
responsible for advancing the unwind state to the next frame.
Fixes#41004
Add pointer masking convenience functions
This PR adds the following public API:
```rust
impl<T: ?Sized> *const T {
fn mask(self, mask: usize) -> *const T;
}
impl<T: ?Sized> *mut T {
fn mask(self, mask: usize) -> *const T;
}
// mod intrinsics
fn mask<T>(ptr: *const T, mask: usize) -> *const T
```
This is equivalent to `ptr.map_addr(|a| a & mask)` but also uses a cool llvm intrinsic.
Proposed in https://github.com/rust-lang/rust/pull/95643#issuecomment-1121562352
cc `@Gankra` `@scottmcm` `@RalfJung`
r? rust-lang/libs-api
It's a common phenomenon that feature stabilizations don't make it into
a particular release, but the version is still inaccurate. Often this
leads to subsequent changes to adjust/correct the version.
Instead, require people to put a placeholder that gets replaced during
beta branching time with the current rust version. That way, there is
no chance that an error can be introduced.
Usage of the placeholder is required on the nightly channel, and forbidden
on the stable and beta channels.
Simplify the arguments to macros generated by the `rustc_queries` proc macro
Very small cleanup. Based on https://github.com/rust-lang/rust/pull/100436 which modifies some of the same code.
r? `@cjgillot`
Merge duplicated CSS rules
I used the [stylelint](https://stylelint.io/user-guide/configure) tool to check for duplicated CSS rules in order to merge them.
r? `@notriddle`
rustdoc: remove incorrect CSS selector `.impl-items table td`
Fixes#100994
This selector was added in c7312fbae4. The bug can be seen at <https://doc.rust-lang.org/1.27.0/alloc/slice/trait.SliceIndex.html#foreign-impls>.
This rule was added to help with a `<table>` that was used for displaying the function signature [src] lockup. That lockup was changed in 34bd2b845b to use flexbox instead, leaving this selector unused (at least, for its original purpose).
rustdoc: remove unused CSS for `hidden-by-*-hider`
This CSS seems to have become obsolete with the move to `<details>` tags,
and its corresponding JavaScript was removed in aee054d05d
rustdoc: omit start/end tags for empty item description blocks
Related to #100952
This is definitely not a complete solution, but it does shrink keysyms/index.html on smithay from 620K to 516K.
Update documentation for `write!` and `writeln!`
https://github.com/rust-lang/rust/pull/37472 added this documentation, but it
needs updating:
- Remove some documentation duplicated between `writeln!` and `write!`
- Update `write!` docs: can now import traits as `_` to avoid conflicts
- Expand example to show how to implement qualified trait names
Fix wrong compiletest filters on Windows
As discussed in [#79334](https://github.com/rust-lang/rust/issues/79334), when calling e.g.
```
python x.py test src/test/ui/expr/compound-assignment/eval-order.rs
```
on Windows, compiletest passes the filter `expr/compound-assignment/eval-order.rs` to libtest, which instead should be `expr\compound-assignment\eval-order.rs`, as that is the file found when collecting tests. This is what I fixed.
I'm not sure how to organize a test for this. Any suggestions?
Make forward compatibility lint deprecated_cfg_attr_crate_type_name deny by default
Turns the forward compatibility lint added by #83744 to deprecate `cfg_attr` usage with `#![crate_type]` and `#![crate_name]` attributes into deny by default. Copying the example from #83744:
```Rust
#![crate_type = "lib"] // remains working
#![cfg_attr(foo, crate_type = "bin")] // will stop working
```
Over 8 months have passed since #83744 was merged so I'd say this gives ample time for people to have been warned, so we can make the warning stronger. No usage was found via grep.app except for one, which was in an unmaintained code base that didn't seem to be used in the open source eco system. The crater run conducted in #83744 also didn't show up anything.
cc #91632 - tracking issue for the lint
Implementation of import_name_type
Fixes#96534 by implementing https://github.com/rust-lang/compiler-team/issues/525
Symbols that are exported or imported from a binary on 32bit x86 Windows can be named in four separate ways, corresponding to the [import name types](https://docs.microsoft.com/en-us/windows/win32/debug/pe-format#import-name-type) from the PE-COFF spec. The exporting and importing binaries must use the same name encoding, otherwise mismatches can lead to link failures due to "missing symbols" or to 0xc0000139 (`STATUS_ENTRYPOINT_NOT_FOUND`) errors when the executable/library is loaded. For details, see the comments on the raw-dylib feature's https://github.com/rust-lang/rust/issues/58713. To generate the correct import libraries for these DLLs, therefore, rustc must know the import name type for each `extern` function, and there is currently no way for users to provide this information.
This change adds a new `MetaNameValueStr` key to the `#[link]` attribute called `import_name_type`, and which accepts one of three values: `decorated`, `noprefix`, and `undecorated`.
A single DLL is likely to export all its functions using the same import type name, hence `import_name_type` is a parameter of `#[link]` rather than being its own attribute that is applied per-function. It is possible to have a single DLL that exports different functions using different import name types, but users could express such cases by providing multiple export blocks for the same DLL, each with a different import name type.
Note: there is a fourth import name type defined in the PE-COFF spec, `IMPORT_ORDINAL`. This case is already handled by the `#[link_ordinal]` attribute. While it could be merged into `import_type_name`, that would not make sense as `#[link_ordinal]` provides per-function information (namely the ordinal itself).
Design decisions (these match the MCP linked above):
* For GNU, `decorated` matches the PE Spec and MSVC rather than the default behavior of `dlltool` (i.e., there will be a leading `_` for `stdcall`).
* If `import_name_type` is not present, we will keep our current behavior of matching the environment (MSVC vs GNU) default for decorating.
* Using `import_name_type` on architectures other than 32bit x86 will result in an error.
* Using `import_name_type` with link kinds other than `"raw-dylib"` will result in an error.
Migrate rustc_driver to SessionDiagnostic
First timer noob here 👋🏽 I'm having a problem understanding how I can retrieve the span, and how to properly construct the error structs to avoid the current compilation errors.
Any help pointing me in the right direction would be much appreciated 🙌🏽
Migrate `rustc_attr` crate diagnostics
Hi!
This is my first PR to the rustc project, excited to be part of the development! This PR is part of the diagnostics effort, to make diagnostics translatable.
`@rustbot` label +A-translation
sugg: suggest the usage of boolean value when there is a typo in the keyword
Fixes https://github.com/rust-lang/rust/issues/100686
This adds a new suggestion when there is a well-known typo
With the following program
```rust
fn main() {
let x = True;
}
```
Now we have the following suggestion
```
error[E0425]: cannot find value `True` in this scope
--> test.rs:2:13
|
2 | let x = True;
| ^^^^ not found in this scope
|
help: you may want to use a bool value instead
|
2 | let x = true;
| ~~~~
error: aborting due to previous error
```
Signed-off-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Diagnostics migr const eval
This PR should eventually contain all diagnostic migrations for the `rustc_const_eval` crate.
r? `@davidtwco`
`@rustbot` label +A-translation
Migrate `rustc_ty_utils` to `SessionDiagnostic`
I have migrated the `rustc_ty_utils` crate to use `SessionDiagnostic`, motivated by the [recent blog post about the diagnostic translation effort](https://blog.rust-lang.org/inside-rust/2022/08/16/diagnostic-effort.html).
This is my first PR to the Rust repository, so if I have missed anything, or anything needs to be changed, please let me know! 😄
`@rustbot` label +A-translation
Migrate ast lowering to session diagnostic
I migrated the whole rustc_ast_lowering crate to session diagnostic *except* the for the use of `span_fatal` at /compiler/rustc_ast_lowering/src/expr.rs#L1268 because `#[fatal(...)]` is not yet supported (see https://github.com/rust-lang/rust/pull/100694).
interpret: remove support for uninitialized scalars
With Miri no longer supporting `-Zmiri-allow-uninit-numbers`, we no longer need to support storing uninit data in a `Scalar`. We anyway already only use this representation for types with *initialized* `Scalar` layout (and we have to, due to partial initialization), so let's get rid of the `ScalarMaybeUninit` type entirely.
I tried to stage this into meaningful commits, but the one that changes `read_immediate` to always trigger UB on uninit is the largest chunk of the PR and I don't see how it could be subdivided.
Fixes https://github.com/rust-lang/miri/issues/2187
r? `@oli-obk`
