Printing "no pattern" as `_` isn't ideal, but better than crashing, and
HIR pretty-printing already has plenty of imperfections. The added `f2`
and `f6` examples are ones that triggered the crash.
Note that some of the added examples are printed badly, e.g.
`fn(, ...)`. The next commit will fix those.
Fixes#139633.
To accurately reflect that RPITIT assoc items don't have a name. This
avoids the use of `kw::Empty` to mean "no name", which is error prone.
Helps with #137978.
Specify `--print info=file` syntax in `--help`
Closes#139794
I moved the listing of information that can be printed to the help string as it's getting rather long and it makes the `[=FILE]` part easier to see
Use `compiletest-ignore-dir` for bootstrap self-tests
Follow-up to #139705 and #139740.
I did another survey pass over `//@ ignore-test` under `tests/`, and this is the only 2 non-tests that should use `compiletest-ignore-dir`.
r? `@Zalathar` (or compiler/bootstrap)
Add test for issue 34834
closes: #34834
This PR adds a UI test for a case where a trait with an associated type using a higher-ranked trait bound (HRTB) failed to compile in Rust 1.55.0 but succeeded starting from 1.56.0.
```rust
pub trait Provides<'a> {
type Item;
}
pub trait Selector: for<'a> Provides<'a> {
type Namespace: PartialEq + for<'a> PartialEq<<Self as Provides<'a>>::Item>;
fn get_namespace(&self) -> <Self as Provides>::Item;
}
pub struct MySelector;
impl<'a> Provides<'a> for MySelector {
type Item = &'a str;
}
impl Selector for MySelector {
type Namespace = String;
fn get_namespace(&self) -> &str {
unimplemented!()
}
}
fn main() {}
```
* ❌ [compile fail (rustc: 1.55.0)](https://godbolt.org/z/T1jY1Ebo6)
* ⭕ [compile pass (rustc: 1.56.0)](https://godbolt.org/z/e4jo11Ma7)
Avoid unused clones in `Cloned<I>` and `Copied<I>`
Avoid cloning in `Cloned<I>` or copying in `Copied<I>` when elements are only needed by reference or not at all. There is already some precedent for this, given that `__iterator_get_unchecked` is implemented, which can skip elements. The reduced clones are technically observable by a user impl of `Clone`.
r? libs-api
re-use `Sized` fast-path
There's an existing fast path for the `type_op_prove_predicate` predicate, checking for trivially `Sized` types, which can be re-used when evaluating obligations within queries. This should improve performance and was found to be beneficial in #137944.
r? types
This change maps the EOPNOTSUPP errno value (95) to std::io::ErrorKind::Unsupported in the decode_error_kind function for Unix platforms. Previously, it was incorrectly mapped to ErrorKind::Uncategorized.
Fixes#139803
Rollup of 8 pull requests
Successful merges:
- #139127 (Fix up partial res of segment in primitive resolution hack)
- #139392 (Detect and provide suggestion for `&raw EXPR`)
- #139767 (Visit place in `BackwardIncompatibleDropHint` statement)
- #139777 (Remove `define_debug_via_print` for `ExistentialProjection`, use regular structural debug impl)
- #139796 (ptr docs: add missing backtics around 'usize')
- #139801 (Add myself to mailmap)
- #139804 (use `realpath` in `bootstrap.py` when creating build-dir)
- #139807 (Improve wording of post-merge report)
r? `@ghost`
`@rustbot` modify labels: rollup
use `realpath` in `bootstrap.py` when creating build-dir
Fixes#139800
r? `@jieyouxu`
My use case for `./build` being a symlink is this: my "default" ~~partition~~ btrfs subvolume is snapshotted/backed up. I don't want to backup target-likes, so I move them to a special subvolume which isn't backed up. `./build` is a symlink into that subvolume. (`build.build-dir` configuration is not fully sufficient, it is still nice to be able to check build files with `ls ./build` or call tools from there)
ptr docs: add missing backtics around 'usize'
We almost always have the backticks, except here... so let's just fix that. Barely worth a PR but it's user-visible docs so here we go.
Remove `define_debug_via_print` for `ExistentialProjection`, use regular structural debug impl
The pretty print impl for `ExistentialProjection` always prints `AssocItem = Ty`:
6e83046233/compiler/rustc_middle/src/ty/print/pretty.rs (L3293-L3299)
We can't change this, b/c it's used for both pretty printing dyn types and for legacy symbol mangling.
Unfortunately, we also use this printing procedure for `Debug` impls. That means that it leaves out the *trait name* and *trait args* when debug printing an `ExistentialProjection` (or an `ExistentialPredicate` which has a variant for `ExistentialProjection`). This leads to awkward situations, like the two seemingly identical existential projection predicates present in a `dyn Trait` type using the definition below:
```rust
trait Super { type Assoc; }
trait Foo: Super<A, Assoc = i32> + Super<B, Assoc = i32> {}
```
Namely, they both just render as `Projection(Assoc = i32)`! This makes debugging `dyn Trait` type system bugs really hard, so let's use the *regular* debug impl for `ExistentialProjection`.
Visit place in `BackwardIncompatibleDropHint` statement
Remove a weird hack from the `LocalUpdater` where we were manually visiting the place stored in a `StatementKind::BackwardIncompatibleDropHint` because the MIR visitor impls weren't doing so.
Also, clean up `BackwardIncompatibleDropHint`s in `CleanupPostBorrowck`, since they're not needed for runtime MIR.
Detect and provide suggestion for `&raw EXPR`
When emitting an error in the parser, and we detect that the previous token was `raw` and we *could* have consumed `const`/`mut`, suggest that this may have been a mistyped raw ref expr. To do this, we add `const`/`mut` to the expected token set when parsing `&raw` as an expression (which does not affect the "good path" of parsing, for the record).
This is kind of a rudimentary error improvement, since it doesn't actually attempt to recover anything, leading to some other knock-on errors b/c we still treat `&raw` as the expression that was parsed... but at least we add the suggestion! I don't think the parser grammar means we can faithfully recover `&raw EXPR` early, i.e. during `parse_expr_borrow`.
Fixes#133231
Fix up partial res of segment in primitive resolution hack
There is a hack in the resolver:
```
// In `a(::assoc_item)*` `a` cannot be a module. If `a` does resolve to a module we
// don't report an error right away, but try to fallback to a primitive type.
```
This fixes up the resolution for primitives which would otherwise resolve to a module, but we weren't also updating the res of the path segment, leading to weird diagnostics.
We explicitly call `self.r.partial_res_map.insert` instead of `record_partial_res` b/c we have recorded a partial res already, and we specifically want to override it.
cc https://github.com/rust-lang/rust/issues/139095#issuecomment-2764371934
