Rollup of 4 pull requests
Successful merges:
- #71398 (Add `RefCell::take`)
- #71663 (Fix exceeding bitshifts not emitting for assoc. consts (properly this time, I swear!))
- #71726 (Suggest deref when coercing `ty::Ref` to `ty::RawPtr` with arbitrary mutability)
- #71808 (Add long error explanation for E0539)
Failed merges:
r? @ghost
Suggest deref when coercing `ty::Ref` to `ty::RawPtr` with arbitrary mutability
Fixes#71676
1. Implement dereference suggestion when coercing `ty::Ref` to `ty::RawPtr` with arbitrary mutability.
2. Extract the dereference steps into `deref_steps()`, which removes all the `use` and `pub` noise introduced by last PR #71540, and makes the code more readable.
3. Use the `remove_prefix()` closure which makes the prefix removal more readable.
4. Introduce `Applicability` as a return value of `check_ref` to suggest `Applicability::Unspecified` suggestion.
**Special**: I found it is not possible to genereate `Applicability::MachineApplicable` suggestion for situation like this:
```rust
use std::ops::Deref;
use std::ops::DerefMut;
struct Bar(u8);
struct Foo(Bar);
struct Emm(Foo);
impl Deref for Bar{
type Target = u8;
fn deref(&self) -> &Self::Target {
&self.0
}
}
impl Deref for Foo {
type Target = Bar;
fn deref(&self) -> &Self::Target {
&self.0
}
}
impl Deref for Emm {
type Target = Foo;
fn deref(&self) -> &Self::Target {
&self.0
}
}
impl DerefMut for Bar{
fn deref_mut(&mut self) -> &mut Self::Target {
&mut self.0
}
}
impl DerefMut for Foo {
fn deref_mut(&mut self) -> &mut Self::Target {
&mut self.0
}
}
impl DerefMut for Emm {
fn deref_mut(&mut self) -> &mut Self::Target {
&mut self.0
}
}
fn main() {
let a = Emm(Foo(Bar(0)));
let _: *mut u8 = &a; //~ ERROR mismatched types
}
```
We may suggest `&mut ***a` here, but the `a` is not declared as mutable variable. And also when processing HIR, it's not possible to check if `a` is declared as a mutable variable (currently we do borrow checking with MIR). So we cannot ensure that suggestion when coercing immutable reference to mutable pointer is always machine applicable. Therefore I added a `Applicability` return value in `check_ref()`. And move the `immutable reference -> mutable pointer` situation into a sperate test file without `run-rustfix`. (It seems that `run-rustfix` will also adopt `Applicability::Unspecified` suggestion, which is strange)
Fix exceeding bitshifts not emitting for assoc. consts (properly this time, I swear!)
Fixes#69021 and fixes#71353.
As described in https://github.com/rust-lang/rust/issues/71353#issuecomment-617901923, this PR:
- adds a variant of `try_validation!` called `try_validation_pat!` that allows specific failures to be turned into validation failures (but returns the rest, unchanged), and
- allows `InvalidProgram` to be returned out of validation
r? @RalfJung
Add `RefCell::take`
Add `RefCell::take` to match `Cell` and `Option`.
I also changed a couple of calls to `.replace` to `.take`.
Tracking issue is #71395.
This is my first contribution, please tell me if there's anything I could improve, thanks!
typeck: always expose explicit enum discriminant `AnonConst`s' parent in `generics_of`.
This is similar to #70452 but for explicit `enum` discriminant constant expressions.
However, unlike #70452, this PR should have no effect on stable code, as while it alleviates #43408 errors, there is no way to actually compile an `enum` with generic parameters *and* explicit discriminants, without `#![feature(arbitrary_enum_discriminant)]`, as explicit discriminant expression don't count as uses of parameters (if they did, they would count as invariant uses).
<hr/>
There's also 2 other commits here, both related to #70453:
* "ty: use `delay_span_bug` in `ty::AdtDef::eval_explicit_discr`." - hides the ICEs demonstrated on #70453, when there are other errors (which the next commit adds)
* "typeck/wfcheck: require that explicit enum discriminants const-evaluate succesfully." - closes#70453 by picking alternative "2", i.e. erroring when a discriminant doesn't fully const-evaluate from the perspective of the `enum` definition
In the future, it might be possible to allow `enum` discriminants to actually depend on parameters, but that will likely require #68436 + some way to restrict the values so no two variants can end up with overlapping discriminants.
As this PR would close#70453, it shouldn't be merged until a decision is reached there.
r? @nikomatsakis
Decode qualifs for associated const defaults
Fixes#71734.
We encode qualifs for associated constants, but never expected to decode the qualifs for defaulted associated consts. Fix this, and test that associated const defaults have the correct qualifs cross-crate.
r? @tmandry
Implement `confusable_idents` lint.
This collects all identifier symbols into `ParseSession` and examines them within the non-ascii-idents lint.
The skeleton generation part needs to be added to `unicode-security` crate. Will update this PR when the crate is updated.
r? @petrochenkov
EDIT: also included the `concat_idents` part.
Implement RFC 2523, `#[cfg(version(..))]`
Hi! This is my first contribution to rust, I hope I didn't miss anything. I tried to implement this feature so that `#[cfg(version(1.44.0))]` works but the parser was printing an error that I wasn't sure how to fix so I just opted for implementing `#[cfg(version("1.44.0"))]` (note the quotes).
Tracking issue: #64796
The extracted function can be used by the rest of bootstrap to detect if we've
already built an up-to-date LLVM (and so it's safe for us to either request it
or pretend it exists).
Rollup of 6 pull requests
Successful merges:
- #71712 (Miri: port error backtraces to std::backtrace)
- #71736 (bootstrap: also apply unused-attributes hack without deny_warnings)
- #71738 (remove AllocId generalization of Pointer)
- #71739 (remove obsolete comment)
- #71781 (Uncomment test code for failure to use `Box::pin`)
- #71782 (Use a non-existent test path instead of clobbering /dev/null)
Failed merges:
r? @ghost
