Suggest Upgrading Compiler for Gated Features
This PR addresses #117318
I have a few questions:
1. Do we want to specify the current version and release date of the compiler? I have added this in via environment variables, which I found in the code for the rustc cli where it handles the `--version` flag
a. How can I handle the changing message in the tests?
3. Do we want to only show this message when the compiler is old?
a. How can we determine when the compiler is old?
I'll wait until we figure out the message to bless the tests
Move platform modules into `sys::pal`
This is the initial step of #117276. `sys` just re-exports everything from the current `sys` for now, I'll move the implementations for the individual features one-by-one after this PR merges.
Taint `_` placeholder types in trait impl method signatures
We report an error right below for them, but that kind of broken type can cause subsequent ICEs.
fixes#119867
Allow `~const` on associated type bounds again
This follows from [this Zulip discussion](https://rust-lang.zulipchat.com/#narrow/stream/419616-t-compiler.2Fproject-const-traits/topic/projections.20on.20.28~.29const.20Trait.20.26.20.28~.29const.20assoc.20ty.20bounds).
Basically in my opinion, it makes sense to allow `~const` on associated type bounds again since they're quite useful even though we haven't implemented the proposed syntax `<Ty as ~const Trait>::Proj`/`<Ty as const Trait>::Proj` yet; that can happen as a follow-up.
This already allows more code to compile since `T::Assoc` where `T` is a type parameter and where the predicate `<T as ~const Trait>` is in the environment gets elaborated to (pseudo) `<T as ~const Trait>::Assoc`.
```rs
#[const_trait]
trait Trait {
type Assoc: ~const Trait;
fn func() -> i32;
}
const fn function<T: ~const Trait>() -> i32 {
T::Assoc::func()
}
```
`~const` associated type bounds also work together with `const` bounds:
```rs
struct Type<const N: i32>;
fn procedure<T: const Trait>() -> Type<{ T::Assoc::func() }> { // `Trait` comes from above
Type
}
```
NB: This PR also starts allowing `~const` bounds in the generics and the where-clause of trait associated types since it's trivial to support them. However, I don't know if those bounds are actually useful. Maybe we should continue to reject them?
For reference, it wouldn't make any sense to allow `~const Trait` in GACs (generic associated constants, `generic_const_items`) because they'd be absolutely useless (contrary to `const Trait`).
~~[``@]rustbot`` ping project-const-traits~~
r? project-const-traits
Varargs support for system ABI
This PR allows functions with the `system` ABI to be variadic (under the `extended_varargs_abi_support` feature tracked in #100189). On x86 windows, the `system` ABI is equivalent to `C` for variadic functions. On other platforms, `system` is already equivalent to `C`.
Fixes#110505
Overhaul `-Ztreat-err-as-bug`
It's current behaviour is surprising, in a bad way. This also makes the implementation more complex than it needs to be.
r? `@oli-obk`
Add explicit `none()` value variant in check-cfg
This PR adds an explicit none value variant in check-cfg values: `values(none())`.
Currently the only way to define the none variant is with an empty `values()` which means that if someone has a cfg that takes none and strings they need to use two invocations: `--check-cfg=cfg(foo) --check-cfg=cfg(foo, values("bar"))`.
Which would now be `--check-cfg=cfg(foo, values(none(),"bar"))`, this is simpler and easier to understand.
`--check-cfg=cfg(foo)`, `--check-cfg=cfg(foo, values())` and `--check-cfg=cfg(foo, values(none()))` would be equivalent.
*Another motivation for doing this is to make empty `values()` actually means no-values, but this is orthogonal to this PR and adding `none()` is sufficient in it-self.*
`@rustbot` label +F-check-cfg
r? `@petrochenkov`
Update cargo
8 commits in 3e428a38a34e820a461d2cc082e726d3bda71bcb..84976cd699f4aea56cb3a90ce3eedeed9e20d5a5
2024-01-09 20:46:36 +0000 to 2024-01-12 15:55:43 +0000
- fix(resolver): do not panic when sorting empty summaries (rust-lang/cargo#13287)
- Implementation of shallow libgit2 fetches behind an unstable flag (rust-lang/cargo#13252)
- Add documentation entry for unstable `--output-format` flag (rust-lang/cargo#13284)
- doc: add `public` info in `cargo-add` man page. (rust-lang/cargo#13272)
- More docs on prerelease compat (rust-lang/cargo#13286)
- Add unstable `--output-format` option to `cargo rustdoc` (rust-lang/cargo#12252)
- feat: Add `rustc` style errors for manifest parsing (rust-lang/cargo#13172)
- Document why `du` function uses mutex (rust-lang/cargo#13273)
r? ghost
`-Ztreat-err-as-bug` treats normal errors and delayed bugs equally,
which can lead to some really surprising results.
This commit changes `-Ztreat-err-as-bug` so it ignores delayed bugs,
unless they get promoted to proper bugs and are printed.
This feels to me much simpler and more logical. And it simplifies the
implementation:
- The `-Ztreat-err-as-bug` check is removed from in
`DiagCtxt::{delayed_bug,span_delayed_bug}`.
- `treat_err_as_bug` doesn't need to count delayed bugs.
- The `-Ztreat-err-as-bug` panic message is simpler, because it doesn't
have to mention delayed bugs.
Output of delayed bugs is now more consistent. They're always printed
the same way. Previously when they triggered `-Ztreat-err-as-bug` they
would be printed slightly differently, via `span_bug` in
`span_delayed_bug` or `delayed_bug`.
A minor behaviour change: the "no errors encountered even though
`span_delayed_bug` issued" printed before delayed bugs is now a note
rather than a bug. This is done so it doesn't get counted as an error
that might trigger `-Ztreat-err-as-bug`, which would be silly.
This means that if you use `-Ztreat-err-as-bug=1` and there are no
normal errors but there are delayed bugs, the first delayed bug will be
shown (and the panic will happen after it's printed).
Also, I have added a second note saying "those delayed bugs will now be
shown as internal compiler errors". I think this makes it clearer what
is happening, because the whole concept of delayed bugs is non-obvious.
There are some test changes.
- equality-in-canonical-query.rs: Minor output changes, and the error
count reduces by one because the "no errors encountered even though
`span_delayed_bug` issued" message is no longer counted as an error.
- rpit_tait_equality_in_canonical_query.rs: Ditto.
- storage-live.rs: The query stack disappears because these delayed bugs
are now printed at the end, rather than when they are created.
- storage-return.rs, span_delayed_bug.rs: now need
`-Zeagerly-emit-delayed-bugs` because they need the delayed bugs
emitted immediately to preserve behaviour.
Fix unused_parens issue when cast is followed LT
Fixes#117142
The original check only checks `a as (i32) < 0`, this fix extends it to handle `b + a as (i32) < 0`.
A better way is maybe we suggest `(a as i32) < 0` instead of suppressing the warning, maybe following PR could improve it.
Rollup of 6 pull requests
Successful merges:
- #119817 (Remove special-casing around `AliasKind::Opaque` when structurally resolving in new solver)
- #119819 (Check rust lints when an unknown lint is detected)
- #119872 (Give me a way to emit all the delayed bugs as errors (add `-Zeagerly-emit-delayed-bugs`))
- #119877 (Add more information to `visit_projection_elem`)
- #119884 (Rename `--env` option flag to `--env-set`)
- #119885 (Revert #113923)
r? `@ghost`
`@rustbot` modify labels: rollup
Add more information to `visit_projection_elem`
Without the starting place, it's hard to retrieve any useful information from visiting a projection.
Note: I still need to add a test.
Give me a way to emit all the delayed bugs as errors (add `-Zeagerly-emit-delayed-bugs`)
This is probably a *better* way to inspect all the delayed bugs in a program that what exists currently (and therefore makes it very easy to choose the right number `N` with `-Zemit-err-as-bug=N`, though I guess the naming is a bit ironic when you pair both of the flags together, but that feels like naming bikeshed more than anything).
This pacifies my only concern with https://github.com/rust-lang/rust/pull/119871#issuecomment-1888170259, because (afaict?) that PR doesn't allow you to intercept a delayed bug's stack trace anymore, which as someone who debugs the compiler a lot, is something that I can *promise* that I do.
r? `@nnethercote` or `@oli-obk`
Remove special-casing around `AliasKind::Opaque` when structurally resolving in new solver
This fixes a few inconsistencies around where we don't eagerly resolve opaques to their (locally-defined) hidden types in the new solver. It essentially allows this code to work:
```rust
fn main() {
type Tait = impl Sized;
struct S {
i: i32,
}
let x: Tait = S { i: 0 };
println!("{}", x.i);
}
```
Since `Tait` is defined in `main`, we are able to poke through the type of `x` with deref.
r? lcnr
Exhaustiveness: track overlapping ranges precisely
The `overlapping_range_endpoints` lint has false positives, e.g. https://github.com/rust-lang/rust/issues/117648. I expected that removing these false positives would have too much of a perf impact but never measured it. This PR is an experiment to see if the perf loss is manageable.
r? `@ghost`
Register even erroneous impls
Otherwise the specialization graph fails to pick it up, even though other code assumes that all impl blocks have an entry in the specialization graph.
also includes an unrelated cleanup of the specialization graph query
fixes #119827
Set `c_str_literals` stabilization version back to `CURRENT_RUSTC_VERSION`
`c_str_literals`'s stabilization has been delayed to 1.77 (https://github.com/rust-lang/rust/pull/119528).