Migrate the standard library from using the external `cfg_if` crate to
using the now-built-in `cfg_select` macro.
This does not yet eliminate the dependency from
`library/std/Cargo.toml`, because while the standard library itself no
longer uses `cfg_if`, it also incorporates the `backtrace` crate, which
does.
Migration assisted by the following vim command (after selecting the
full `cfg_if!` invocation):
```
'<,'>s/\(cfg_if::\)\?cfg_if/cfg_select/ | '<,'>s/^\( *\)} else {/\1}\r\1_ => {/c | '<,'>s/^\( *\)} else if #\[cfg(\(.*\))\] /\1}\r\1\2 => /e | '<,'>s/if #\[cfg(\(.*\))\] {/\1 => {/e
```
This is imperfect, but substantially accelerated the process. This
prompts for confirmation on the `} else {` since that can also appear
inside one of the arms. This also requires manual intervention to handle
any multi-line conditions.
Revert "Partially outline code inside the panic! macro".
This reverts https://github.com/rust-lang/rust/pull/115670
Without any tests/benchmarks that show some improvement, it's hard to know whether the change had any positive effect. (And if it did, whether that effect is still achieved today.)
Revert "Partially outline code inside the panic! macro".
This reverts https://github.com/rust-lang/rust/pull/115670
Without any tests/benchmarks that show some improvement, it's hard to know whether the change had any positive effect. (And if it did, whether that effect is still achieved today.)
replace multiple `if-let`s with `match`
turn the condition into a match guard
allows removing the `else` branch
replace `Vec::append` with `extend`
don't need the second vec after this operation anyway
remove `return`s
Stabilize `const_exposed_provenance` feature
This closes [tracking issue](https://github.com/rust-lang/rust/issues/144538) and stabilises `fn with_exposed_provenance` and `fn with_exposed_provenance_mut` in const
Do not copy files in `copy_src_dirs` in dry run
This reduces the time to run the current 9 dist snapshot tests from ~24s to ~2s on my PC.
r? `@jieyouxu`
Fix tracing debug representation of steps without arguments in bootstrap
I was wondering why I see `lainSourceTarbal` in tracing logs...
r? `@jieyouxu`
Remove duplicated tracing span in bootstrap
`trace_cmd` is now called also in the `stream` method, so including it also here was duplicating command spans.
r? `@jieyouxu`
fix(tests/rmake/wasm-unexpected-features): change features from `WASM1` to `MVP`
missed this in rust-lang/rust#145275
since test calls `rustc` with `-C target-cpu mvp`
try-job: `test-various`
Implement `#[derive(From)]`
Implements the `#[derive(From)]` feature ([tracking issue](https://github.com/rust-lang/rust/issues/144889), [RFC](https://github.com/rust-lang/rfcs/pull/3809)).
It allows deriving the `From` impl on structs and tuple structs with exactly one field. Some implementation notes:
- I wasn't exactly sure which spans to use in the derive generating code, so I just used `span` everywhere. I don't know if it's the Right Thing To Do. In particular the errors when `#[derive(From)]` is used on a struct with an unsized field are weirdly duplicated.
- I had to solve an import stability problem, where if I just added the unstable `macro From` to `core::convert`, previously working code like `use std::convert::From` would suddenly require an unstable feature gate, because rustc would think that you're trying to import the unstable macro. `@petrochenkov` suggested that I add the macro the the core prelude instead. This has worked well, although it only works in edition 2021+. Not sure if I botched the prelude somehow and it should live elsewhere (?).
- I had to add `Ty::AstTy`, because the `from` function receives an argument with the type of the single field, and the existing variants of the `Ty` enum couldn't represent an arbitrary type.
`apply_member_constraints`: fix placeholder check
Checking whether the member region is *an existential region from a higher universe* is just wrong and I am pretty sure we've added that check by accident as the naming was just horribly confusing before rust-lang/rust#140466.
I've encountered this issue separately while working on rust-lang/rust#139587, but feel like it's probably easier to separately FCP this change. This allows the following code to compile
```rust
trait Proj<'a> {
type Assoc;
}
impl<'a, 'b, F: FnOnce() -> &'b ()> Proj<'a> for F {
type Assoc = ();
}
fn is_proj<F: for<'a> Proj<'a>>(f: F) {}
fn define<'a>() -> impl Sized + use<'a> {
// This adds a use of `opaque::<'a>` with hidden type `&'unconstrained_b ()`.
// 'unconstrained_b is an inference variable from a higher universe as it gets
// created inside of the binder of `F: for<'a> Proj<'a>`. This previously
// caused us to not apply member constraints. We now do, constraining
// it to `'a`.
is_proj(define::<'a>);
&()
}
fn main() {}
```
This should not be breaking change, even in theory. Applying member constraints is incomplete in rare circumstances which means that applying them in more cases can cause spurious errors, cc rust-lang/rust#140569/rust-lang/rust#142073. However, as we always skipped these member regions in `apply_member_constraints` the skipped region is guaranteed to cause an error in `check_member_constraints` later on.
Fix adjacent code
Fix duplicate warning; merge test into `tests/ui-fulldeps/internal-lints`
Use `rustc_middle::ty::FnSig::inputs`
Address two review comments
- https://github.com/rust-lang/rust/pull/139345#discussion_r2109006991
- https://github.com/rust-lang/rust/pull/139345#discussion_r2109058588
Use `Instance::try_resolve`
Import `rustc_middle::ty::Ty` as `Ty` rather than `MiddleTy`
Simplify predicate handling
Add more `#[allow(rustc::potential_query_instability)]` following rebase
Remove two `#[allow(rustc::potential_query_instability)]` following rebase
Address review comment
Update compiler/rustc_lint/src/internal.rs
Co-authored-by: lcnr <rust@lcnr.de>
