Remove `box_syntax`
r? `@Nilstrieb`
This removes the feature `box_syntax`, which allows the use of `box <expr>` to create a Box, and finalises removing use of the feature from the compiler. `box_patterns` (allowing the use of `box <pat>` in a pattern) is unaffected.
It also removes `ast::ExprKind::Box` - the only way to create a 'box' expression now is with the rustc-internal `#[rustc_box]` attribute.
As a temporary measure to help users move away, `box <expr>` now parses the inner expression, and emits a `MachineApplicable` lint to replace it with `Box::new`
Closes#49733
Strengthen state tracking in const-prop
Some/many of the changes are replicated between both the const-prop lint and the const-prop optimization.
Behaviour changes:
- const-prop opt does not give a span to propagated values. This was useless as that span's primary purpose is to diagnose evaluation failure in codegen.
- we remove the `OnlyPropagateInto` mode. It was only used for function arguments, which are better modeled by a write before entry.
- the tracking of assignments and discriminants make clearer that we do nothing in `NoPropagation` mode or on indirect places.
Gate usages of `dyn*` and const closures in macros
We silently accepted `dyn*` and const closures in macros as long as they didn't expand to anything containing these experimental features, unlike other gated features such as `for<'a>` binders on closures, etc. Let's not do that, to make sure nobody begins relying on this.
Commit some tests for the new solver + lazy norm
Also consolidate `typeck/lazy-norm` into `traits/new-solver`, since it's not really useful to maintain a distinction, like when a test really is due to "lazy norm" or "the new solver" (usually both!)
Add suggestion to diagnostic when user has array but trait wants slice. (rebased)
Rebase of #91314, except for change to multipart suggestion
Resolves#90528
r? ``@compiler-errors`` since you requested the multipart suggestion
I was looking into `array::IntoIter` optimization, and noticed that it wasn't annotating the loads with `noundef` for simple things like `array::IntoIter<i32, N>`.
Turned out to be a more general problem as `MaybeUninit::assume_init_read` isn't marking the load as initialized (<https://rust.godbolt.org/z/Mxd8TPTnv>), which is unfortunate since that's basically its reason to exist.
This PR lowers `ptr::read(p)` to `copy *p` in MIR, which fortuitiously also improves the IR we give to LLVM for things like `mem::replace`.
Rollup of 9 pull requests
Successful merges:
- #104363 (Make `unused_allocation` lint against `Box::new` too)
- #106633 (Stabilize `nonzero_min_max`)
- #106844 (allow negative numeric literals in `concat!`)
- #108071 (Implement goal caching with the new solver)
- #108542 (Force parentheses around `match` expression in binary expression)
- #108690 (Place size limits on query keys and values)
- #108708 (Prevent overflow through Arc::downgrade)
- #108739 (Prevent the `start_bx` basic block in codegen from having two `Builder`s at the same time)
- #108806 (Querify register_tools and post-expansion early lints)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
allow negative numeric literals in `concat!`
Fixes#106837
While *technically* negative numeric literals are implemented as unary operations, users can reasonably expect that negative literals are treated the same as positive literals.
Make `unused_allocation` lint against `Box::new` too
Previously it only linted against `box` syntax, which likely won't ever be stabilized, which is pretty useless. Even now I'm not sure if it's a meaningful lint, but it's at least something 🤷
This means that code like the following will be linted against:
```rust
Box::new([1, 2, 3]).len();
f(&Box::new(1)); // where f : &i32 -> ()
```
The lint works by checking if a `Box::new` (or `box`) expression has an a borrow adjustment, meaning that the code that first stores the box in a variable won't be linted against:
```rust
let boxed = Box::new([1, 2, 3]); // no lint
boxed.len();
```
Honor current target when checking conditional compilation values
This is fixed by simply using the currently registered target in the current session. We need to use it because of target json that are not by design included in the rustc list of targets.
Fixes https://github.com/rust-lang/rust/issues/108941
Move __thread_local_inner to sys
Move `__thread_local_inner` macro in `crate:🧵:local` to `crate::sys`. Initially, I was thinking about removing this macro completely, but I could not find a way to create the generic statics without macros, so in the end, I just moved to code around.
This probably will need a rebase once https://github.com/rust-lang/rust/pull/108917 is merged
r? ``@workingjubilee``
Add note when matching token with nonterminal
The current error message is _really_ confusing. The implementation is slightly hacky, but not that much more hacky than all this nonterminal stuff..
r? ``@petrochenkov``
Relax ordering rules for `asm!` operands
The `asm!` and `global_asm!` macros require their operands to appear strictly in the following order:
- Template strings
- Positional operands
- Named operands
- Explicit register operands
- `clobber_abi`
- `options`
This is overly strict and can be inconvienent when building complex `asm!` statements with macros. This PR relaxes the ordering requirements as follows:
- Template strings must still come before all other operands.
- Positional operands must still come before named and explicit register operands.
- Named and explicit register operands can be freely mixed.
- `options` and `clobber_abi` can appear in any position after the template strings.
r? ```````@joshtriplett```````
Don't even try to combine consts with incompatible types
~I left a more detailed explanation for why this fixes this issue in the UI test, but in general, we should not try to unify const infer vars and rigid consts if they have incompatible types. That's because we don't want something like a `ConstArgHasType` predicate to suddenly go from passing to failing, or vice versa, due to a shallow resolve.~
1. Use the `type_of` for a parameter in `try_eval_lit_or_param`, instead of the "expected" type from a `WithOptConstParam` def id.
2. Don't combine consts that have incompatible types.
Fixes#108781
feat: implement better error for manual impl of `Fn*` traits
Fixes#39259
cc `@estebank` (you gave me some advice in the linked issue, would you like to review?)
Do not ICE when we have fn pointer `Fn` obligations with bound vars in the self type
We never supported solving `for<'a> fn(&'a ()): Fn(&'a ())` -- I tried to add that support in #104929, but iirc `@lcnr` wanted to support this more generally by eagerly instantiating trait predicate binders with placeholders. That never happened due to blockers in the old solver, but we probably shouldn't ICE in any case.
On the bright side, this passes on the new solver :^)
Emit alias-eq when equating numeric var and projection
This doesn't fix everything having to do with projections and infer vars, but it does fix a common case I saw in HIR typeck.
r? `@lcnr`
This allows removing all the platform-dependent code from `library/std/src/thread/local.rs` and `library/std/src/thread/mod.rs`
Signed-off-by: Ayush Singh <ayushsingh1325@gmail.com>
Introduce a no-op `PlaceMention` statement for `let _ =`.
Fixes https://github.com/rust-lang/rust/issues/54003
Fixes https://github.com/rust-lang/rust/issues/80059
Split from https://github.com/rust-lang/rust/pull/101500
This PR introduces a new `PlaceMention` statement dedicated to matches that neither introduce bindings nor ascribe types. Without this, all traces of the match would vanish from MIR, making it impossible to diagnose unsafety or use in #101500.
This allows to mark `let _ = <unsafe union access or dereference>` as requiring an unsafe block.
Nominating for lang team, as this introduces an extra error.
This is fixed by simply using the currently registered target in the
current session. We need to use it because of target json that are not
by design included in the rustc list of targets.
feat/refactor: improve errors in case of ident with number at start
Improve parser code when we parse a integer (or float) literal but expect an identifier. We emit an error message saying that identifiers can't begin with numbers. This PR just improves that code and expands it to all identifiers. Note that I haven't implemented error recovery (this didn't exist before anyway), I might do that in a follow up PR.
Rollup of 8 pull requests
Successful merges:
- #108754 (Retry `pred_known_to_hold_modulo_regions` with fulfillment if ambiguous)
- #108759 (1.41.1 supported 32-bit Apple targets)
- #108839 (Canonicalize root var when making response from new solver)
- #108856 (Remove DropAndReplace terminator)
- #108882 (Tweak E0740)
- #108898 (Set `LIBC_CHECK_CFG=1` when building Rust code in bootstrap)
- #108911 (Improve rustdoc-gui/tester.js code a bit)
- #108916 (Remove an unused return value in `rustc_hir_typeck`)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Canonicalize root var when making response from new solver
During trait solving, if we equate two inference variables `?0` and `?1` but don't equate them with any rigid types, then `InferCtxt::probe_ty_var` will return `Err` for both of these. The canonicalizer code will then canonicalize the variables independently(!), and the response will not reflect the fact that these two variables have been made equal.
This hinders inference and I also don't think it's sound? I haven't thought too much about it past that, so let's talk about it.
r? ``@lcnr``
Suppress copy impl error when post-normalized type references errors
Suppress spurious errors from the `Copy` impl validity check when fields have bad types *post*-normalization, instead of just pre-normalization.
----
The const-generics test regressed recently due to #107965, cc `````@BoxyUwU.`````
* I think it's because `[_; 0u32]: Copy` now fails to hold because a nested obligation `ConstArgHasType(0u32, usize)` fails.
* It's interesting that `[const_error]` shows up in the type only after normalization, though, but I'm pretty sure that it's due to the evaluate call that happens when normalizing unevaluated consts.
This was previously needed because the indirection used to hide some unexplained lifetime errors, which it turned out were related to the `min_choice` algorithm.
Removing the indirection also solves a couple of cycle errors, large moves and makes async blocks support the `#[track_caller]` annotation.
always resolve to universal regions if possible
`RegionConstraintCollector::opportunistic_resolve_var`, which is used in canonicalization and projection logic, doesn't resolve the region var to an equal universal region. So if we have equated `'static == '1 == '2`, it doesn't resolve `'1` or `'2` to `'static`. Now it does!
Addresses review comment https://github.com/rust-lang/rust/pull/107376#discussion_r1093233687.
r? `@lcnr`
Account for binders correctly when adding default RPITIT method assumption
As of #108203, we install extra projection predicates into the param-env of a default trait method when it has return-position `impl Trait` (or is async).
The implementation didn't account for the fact that it's walking into and out of binders, so we just need to shift all the debruijn indices accordingly when constructing the projection predicates.
Fixes#108579
r? types
Rollup of 7 pull requests
Successful merges:
- #108619 (Remove the option to disable `llvm-version-check`)
- #108728 (infer: fix and improve comments)
- #108731 (feat: impl better help for `.poll()` not found on `impl Future`)
- #108774 (Greatly improve the error messages when `run-make/translation` fails)
- #108805 (Update askama to 0.12 and improve whitespace control)
- #108823 (Add tracking issue for cf-protection to unstable book)
- #108855 (Custom MIR: Support `as` casts)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
feat: impl better help for `.poll()` not found on `impl Future`
Partially address #108572
I'd like to also address suggestions for generalized `Self` parameters as well. That'll be a separate PR.
Use `nuw` when calculating slice lengths from `Range`s
An `assume` would definitely not be worth it, but since the flag is almost free we might as well tell LLVM this, especially on `_unchecked` calls where there's no obvious way for it to deduce it.
(Today neither safe nor unsafe indexing gets it: <https://rust.godbolt.org/z/G1jYT548s>)
fix multiple issues when promoting type-test subject
Multiple interdependent fixes. See linked issues for a short description of each.
When Promoting a type-test `T: 'a` from within the closure back to its parent function, there are a couple pre-existing bugs and limitations. They were exposed by the recent changes to opaque types because the type-test subject (`T`) is no longer a simple ParamTy.
Commit 1:
Fixes#108635Fixes#107426
Commit 2:
Fixes#108639
Commit 3:
Fixes#107516
Do not ICE when failing to normalize in ConstProp.
There is no reason to delay a bug there, as we bubble up the failure as TooGeneric.
Fixes https://github.com/rust-lang/rust/issues/97728
Add regression tests for issue 70919
Desugaring DropAndReplace at MIR build (#107844) fixed#70919.
Add regressions tests, borrowed from #102078, to ensure we check for this in the future.
cc ``@Aaron1011``
const_eval: `implies_by` in `rustc_const_unstable`
Fixes#107605.
Extend support for `implies_by` (from `#[stable]` and `#[unstable]`) to `#[rustc_const_stable]` and `#[rustc_const_unstable]`.
cc ``@steffahn``
An `assume` would definitely not be worth it, but since the flag is almost free we might as well tell LLVM this, especially on `_unchecked` calls where there's no obvious way for it to deduce it.
(Today neither safe nor unsafe indexing gets it: <https://rust.godbolt.org/z/G1jYT548s>)
Desugaring DropAndReplace at MIR build (#107844) fixed issue
70919. Add regressions tests, borrowed from #102078, to ensure we
check for this in the future.
Co-authored-by: Aaron Hill <aa1ronham@gmail.com>
Bless tests and show an introduced unsoundness related to
exits<'a> { forall<'b> { 'a == 'b } }.
We now resolve the var ?a in U0 to the placeholder !b in U1.
Desugaring of drop and replace at MIR build
This commit desugars the drop and replace deriving from an
assignment at MIR build, avoiding the construction of the
`DropAndReplace` terminator (which will be removed in a following PR).
In order to retain the same error messages for replaces a new
`DesugaringKind::Replace` variant is introduced.
The changes in the borrowck are also useful for future work in moving drop elaboration
before borrowck, as no `DropAndReplace` would be present there anymore.
Notes on test diffs:
* `tests/ui/borrowck/issue-58776-borrowck-scans-children`: the assignment deriving from the desugaring kills the borrow.
* `tests/ui/async-await/async-fn-size-uninit-locals.rs`, `tests/mir-opt/issue_41110.test.ElaborateDrops.after.mir`, `tests/mir-opt/issue_41888.main.ElaborateDrops.after.mir`: drop elaboration generates (or reads from) a useless drop flag due to an issue with the dataflow analysis. Will be fixed independently by https://github.com/rust-lang/rust/pull/106430.
See https://github.com/rust-lang/rust/pull/104488 for more context
Label opaque type for 'captures lifetime' error message
Providing more information may help make this somewhat opaque (lol) error message a bit clearer.
Fix another ICE in `point_at_expr_source_of_inferred_type`
Types coming from method probes must only be investigated *structurally*, since they often contain escaping infer variables from generalization and autoderef. We already have a hack in this PR that erases variables from types, so just use that.
Fixes#108664
The note attached to this error is pretty bad:
```
here the type of `primes` is inferred to be `[_]`
```
But that's unrelated to the PR.
---
Side-note: This is a pretty easy to trigger beta regression, so I've nominated it. Alternatively, I'm slightly inclined to remove this code altogether until it can be reformulated to be more accurate and less ICEy.
Deny capturing late-bound non-lifetime param in anon const
Introduce a new AnonConstBoundary so we can detect when we capture a late-bound non-lifetime param with `non_lifetime_binders` enabled.
In the future, we could technically do something like introduce an early-bound parameter on the anon const, and stick the late-bound param in its substs (kinda like how we turn late-bound lifetimes in opaques into early-bound ones). But for now, just deny it so we don't ICE.
Fixes#108191
This commit desugars the drop and replace deriving from an
assignment at MIR build, avoiding the construction of the
DropAndReplace terminator (which will be removed in a followign PR)
In order to retain the same error messages for replaces a new
DesugaringKind::Replace variant is introduced.
Feed queries on impl side for RPITITs when using lower_impl_trait_in_trait_to_assoc_ty
I've added a test for traits that were already working and what I think is probably the last bit of infrastructure work needed.
In following PRs I'm going to start adding things TDD style, tests and code that make it work.
r? `@compiler-errors`
Make `ExprKind` the first field in `thir::Expr`
This makes its `Debug` impl print it first which is useful, as it's the most important part when looking at an expr.
Explain compile-time vs run-time difference in env!() error message
This PR is clarifying error message of `env!()` based on this user question: https://users.rust-lang.org/t/environment-variable-out-dir-is-undefined/90067
It makes it clear that `env!()` is for env variables defined at compile-time. There's special-case help text for common Cargo build script variables.
I've also rearranged the code to avoid allocating error message on the happy path when the env var is defined.
Point error span at Some constructor argument when trait resolution fails
This is a follow up to #108254 and #106477 which extends error span refinement to handle a case which I mistakenly believed was handled in #106477. The goal is to refine the error span depicted below:
```rs
trait Fancy {}
impl <T> Fancy for Option<T> where T: Iterator {}
fn want_fancy<F>(f: F) where F: Fancy {}
fn example() {
want_fancy(Some(5));
// (BEFORE) ^^^^^^^ `{integer}` is not an iterator
// (AFTER) ^ `{integer}` is not an iterator
}
```
I had used a (slightly more complex) example as an illustrative example in #108254 , but hadn't actually turned it into a test, because I had (incorrectly) believed at the time it was covered by existing behavior. It turns out that `Some` is slightly "special" in that it resolves differently from the other `enum` constructors I had tried, and therefore this test was actually broken.
I've now updated the tests to include this example, and fixed the code to correctly resolve the `Some` constructor so that the span of the error is reduced.
Revert stabilization of `#![feature(target_feature_11)]`
This reverts #99767 due to the presence of bugs #108645 and #108646.
cc `@joshtriplett`
cc tracking issue #69098
r? `@ghost`
