Currently we pick "weird" numbers like `1114112` for `None::<char>`. While that's not *wrong*, it's kinda *unnatural* -- a human wouldn't make that choice.
This PR instead picks `-1` for thinge like `None::<char>` -- like clang's `WEOF` -- and `None::<bool>` and such.
Any enums with more than one niched value (so not `Result` nor `Option`) remain as they were before.
Rollup of 9 pull requests
Successful merges:
- rust-lang/rust#146181 (Add intrinsic for launch-sized workgroup memory on GPUs)
- rust-lang/rust#154803 (Fix ICE from cfg_attr_trace )
- rust-lang/rust#155065 (Error on invalid macho section specifier)
- rust-lang/rust#155485 (Add an edge-case test for `--remap-path-prefix` for `rustc` & `rustdoc`)
- rust-lang/rust#155659 (cleanup, restructure and merge `tests/ui/deriving` into `tests/ui/derives`)
- rust-lang/rust#155676 ( Reject implementing const Drop for types that are not const `Destruct` already)
- rust-lang/rust#155696 (Add a higher-level API for parsing attributes)
- rust-lang/rust#155769 (triagebot.toml: Ping Enselic when tests/debuginfo/basic-stepping.rs changes)
- rust-lang/rust#155783 (Do not suggest internal cfg trace attributes)
Reject implementing const Drop for types that are not const `Destruct` already
fixesrust-lang/rust#155618
While there is no soundness or otherwise issue currently, this PR ensures that people get what they expect. It seems wrong to allow implementing `const Drop`, but then the type still can't be dropped at compile-time.
r? @fee1-dead
cleanup, restructure and merge `tests/ui/deriving` into `tests/ui/derives`
As a followup to https://github.com/rust-lang/rust/pull/155615, this PR deletes some outdated tests from these directories, splits up `ui/derives` into smaller directories to roughly group tests by the derive macros they use and moves over all tests from `ui/deriving` into `ui/derives`.
r? @Kivooeo
Error on invalid macho section specifier
The macho section specifier used by `#[link_section = "..."]` is more strict than e.g. the one for elf. LLVM will error when you get it wrong, which is easy to do if you're used to elf. So, provide some guidance for the simplest mistakes, based on the LLVM validation.
Currently compilation fails with an LLVM error, see https://godbolt.org/z/WoE8EdK1K.
The LLVM validation logic is at
a0f0d6342e/llvm/lib/MC/MCSectionMachO.cpp (L199-L203)
LLVM validates the other components of the section specifier too, but it feels a bit fragile to duplicate those checks. If you get that far, hopefully the LLVM errors will be sufficient to get unstuck.
---
sidequest from https://github.com/rust-lang/rust/pull/147811
r? JonathanBrouwer
specifically, is this the right place for this sort of validation? `rustc_attr_parsing` also does some validation.
Add intrinsic for launch-sized workgroup memory on GPUs
Workgroup memory is a memory region that is shared between all
threads in a workgroup on GPUs. Workgroup memory can be allocated
statically or after compilation, when launching a gpu-kernel.
The intrinsic added here returns the pointer to the memory that is
allocated at launch-time.
# Interface
With this change, workgroup memory can be accessed in Rust by
calling the new `gpu_launch_sized_workgroup_mem<T>() -> *mut T`
intrinsic.
It returns the pointer to workgroup memory guaranteeing that it is
aligned to at least the alignment of `T`.
The pointer is dereferencable for the size specified when launching the
current gpu-kernel (which may be the size of `T` but can also be larger
or smaller or zero).
All calls to this intrinsic return a pointer to the same address.
See the intrinsic documentation for more details.
## Alternative Interfaces
It was also considered to expose dynamic workgroup memory as extern
static variables in Rust, like they are represented in LLVM IR.
However, due to the pointer not being guaranteed to be dereferencable
(that depends on the allocated size at runtime), such a global must be
zero-sized, which makes global variables a bad fit.
# Implementation Details
Workgroup memory in amdgpu and nvptx lives in address space 3.
Workgroup memory from a launch is implemented by creating an
external global variable in address space 3. The global is declared with
size 0, as the actual size is only known at runtime. It is defined
behavior in LLVM to access an external global outside the defined size.
There is no similar way to get the allocated size of launch-sized
workgroup memory on amdgpu an nvptx, so users have to pass this
out-of-band or rely on target specific ways for now.
Tracking issue: rust-lang/rust#135516
privacy: Assert that compared visibilities are (usually) ordered
And make "greater than" (`>`) the new primary operation for comparing visibilities instead of "is at least" (`>=`).
`mk_place_elem` appends a single `PlaceElem` to an existing (interned)
projection. The current implementation copies the projection into a
fresh `Vec`, pushes the new element, and re-interns the slice, which
allocates on the heap on every call.
Feed the elements through `mk_place_elems_from_iter` so that
`CollectAndApply`'s hand-unrolled stack fast path (up to 9 elements,
in `rustc_type_ir::interner`) kicks in for the common case of short
projections and the `Vec` allocation is skipped entirely. The behavior
is identical for longer projections (the fast path falls back to a
`Vec` internally).
Do not modify resolver outputs during lowering
Split from https://github.com/rust-lang/rust/pull/142830
I believe this achieves the same thing as https://github.com/rust-lang/rust/pull/153656 but in a much simpler way.
This PR forces AST->HIR lowering to stop mutating resolver outputs. Instead, it manages a few override maps that only live during lowering and are dropped afterwards.
r? @petrochenkov
cc @aerooneqq
The test `tests/debuginfo/basic-stepping.rs` has a history of regressing
for subtle reasons, and has non-obvious expectations. So I'd like to
keep an extra eye on it.
Pass fields to `is_tuple_fields` instead of `SBValue` object
straightforward fix for a logic error. `is_tuple_fields` expects a `list`, so we pass that in instead of the value object.
Coincidentally, this also fixes one of the 3 DI tests that fails on `x86_64-pc-windows-gnu` (`tests/debuginfo/union-smoke.rs`)
Account for `GetSyntheticValue` failures
`GetSyntheticValue` returns an invalid `SBValue` if no synthetic is present. That wasn't a problem before when we were attaching synthetics to every type, but it won't be the case once github.com/rust-lang/rust/pull/155336 or similar lands. Additionally, codelldb subverts `lldb_commands` to apply similar behavior that doesn't attach synthetics to every type, so this fixes a regression there too.
Additionally, I removed 1 useless instance of `GetSyntheticValue`, since pointers should always be `IndirectionSyntheticProvider`, not `DefaultSyntheticProvider`.
bootstrap: Don't clone submodules unconditionally in dry-run
This made it very annoying to debug bootstrap itself, because every `--dry-run` invocation would start out by cloning LLVM, which is almost never necessary. Instead change a few Steps to properly support dry_run when no submodule is checked out.
I tested this by running all of `check`, `build`, `doc`, `dist`, `install`, `vendor`, `clippy`, `fix`, and `miri` with `--dry-run`.
Handle index projections in call destinations in DSE
Since call destinations are evaluated after call arguments, we can't turn copy arguments into moves if the same local is later used as an index projection in the call destination.
DSE call arg optimization: rust-lang/rust#113758
r? @cjgillot
cc @RalfJung
Avoid redundant clone suggestions in borrowck diagnostics
Fixesrust-lang/rust#153886
Removed redundant `.clone()` suggestions.
I found that there are two patterns to handle this issue while I was implementing:
- Should suggest only UFCS
- Should suggest only simple `.clone()`
For the target issue, we can just remove the UFCS (`<Option<String> as Clone>::clone(&selection.1)`) side.
However, for the `BorrowedContentSource::OverloadedDeref` pattern like `Rc<Vec<i32>>`, for instance the `borrowck-move-out-of-overloaded-auto-deref.rs` test case, I think we need to employ the UFCS way. The actual test case is:
```rust
//@ run-rustfix
use std::rc::Rc;
pub fn main() {
let _x = Rc::new(vec![1, 2]).into_iter();
//~^ ERROR [E0507]
}
```
And another error will be shown if we simply use the simple `.clone()` pattern. Like:
```rust
use std::rc::Rc;
pub fn main() {
let _x = Rc::new(vec![1, 2]).clone().into_iter();
}
```
then we will get
```
error[E0507]: cannot move out of an `Rc`
--> src/main.rs:5:14
|
5 | let _x = Rc::new(vec![1, 2]).clone().into_iter();
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^ ----------- value moved due to this method call
| |
| move occurs because value has type `Vec<i32>`, which does not implement the `Copy` trait
|
note: `into_iter` takes ownership of the receiver `self`, which moves value
--> /playground/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/iter/traits/collect.rs:310:18
|
310 | fn into_iter(self) -> Self::IntoIter;
| ^^^^
help: you can `clone` the value and consume it, but this might not be your desired behavior
|
5 - let _x = Rc::new(vec![1, 2]).clone().into_iter();
5 + let _x = <Vec<i32> as Clone>::clone(&Rc::new(vec![1, 2])).into_iter();
|
For more information about this error, try `rustc --explain E0507`.
```
[Rust Playground](https://play.rust-lang.org/?version=stable&mode=debug&edition=2024&gist=7e767bed3f1c573c03642f20f454ed03)
In this case, `Rc::clone` only increments the reference count and returns a new `Rc<Vec<i32>>`; it does not grant ownership of the inner `Vec<i32>`. As a result, calling into_iter() attempts to move the `Vec<i32>`, leading to the same E0507 error again.
On the other hand, in UFCS form:
```
<Vec<i32> as Clone>::clone(&Rc::new(vec![1, 2])).into_iter()
```
This explicitly calls `<Vec<i32> as Clone>::clone`, and the argument `&Rc<Vec<i32>>` is treated as `&Vec<i32>` via Rc’s `Deref` implementation. As a result, the `Vec<i32>` itself is cloned, yielding an owned `Vec<i32>`, which allows `into_iter()` to succeed, if my understanding is correct.
I addressed the issue as far as I could find the edge cases but please advice me if I'm overlooking something.
Rollup of 3 pull requests
Successful merges:
- rust-lang/rust#155754 (make the `core::ffi::va_list` module private)
- rust-lang/rust#155522 (cmse: test returning `MaybeUninit<T>`)
- rust-lang/rust#155741 (std: Refactor BufWriter::flush to use the `?` operator)
cmse: test returning `MaybeUninit<T>`
tracking issue: https://github.com/rust-lang/rust/issues/81391
tracking issue: https://github.com/rust-lang/rust/issues/75835
Some tests from https://github.com/rust-lang/rust/pull/147697 that already work and are useful. Extracting them shrinks that (currently blocked) PR.
The code in `tests/ui/cmse-nonsecure/cmse-nonsecure-call/return-via-stack.rs` checks that `MaybeUninit<T>` is considered abi-compatible with `T`. The code in `tests/ui/cmse-nonsecure/cmse-nonsecure-entry/params-via-stack.rs` really only tests that no errors/warnings are emitted.
r? davidtwco
Permit `{This}` in diagnostic attribute format literals
My motivation was that yesterday I wanted to write something like this and reference `$name` in the string literal.
```rust
pub mod sym {
// stuff here
}
macro_rules! my_macro {
($name:ident $(,)?) => {{
#[diagnostic::on_unknown(
message = "this is not present in symbol table",
note = "you must add it to rustc_span::symbol::symbol!"
)]
use sym::$name as name;
// ...
}}
}
```
That is (as far as I can tell) impossible or at least very unergonomic. This adds the ability to just reference the name of the item the attribute is on. I imagine that's useful for use inside macros generally, so it's also added for some other attributes.
The affected attributes are all unstable, it is not implemented for diagnostic::on_unimplemented (will do in its own PR).
Note that `{This}` is already usable in `#[rustc_on_unimplemented]`, so this does not implement it but just enables some more.
This PR also migrates one lint away from AttributeLintKind, and improves the messages for that lint.
