There is another test named `if.rs` in `tests/coverage-map/status-quo/`, so
this test stands in the way of flattening that directory into its parent.
Fortunately both tests are more-or-less equivalent, so removing this one is
fine.
This is a step towards being able to unify the two coverage test directories.
There are two tests that require adjustment:
- `overflow.rs` requires an explicit `-Coverflow-checks=yes`
- `sort_groups.rs` is sensitive to provably unused instantiations
Emit explanatory note for move errors in packed struct derives
Derive expansions for packed structs with non-`Copy` fields cause move errors because they prefer copying over borrowing since borrowing the fields of a packed struct can result in unaligned access.
This underlying cause of the errors, however, is not apparent to the user. This PR adds a diagnostic note to make it clear to the user (the new note is on the second last line):
```
tests/ui/derives/deriving-with-repr-packed-move-errors.rs:13:16
|
12 | #[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Clone, Default)]
| ----- in this derive macro expansion
13 | struct StructA(String);
| ^^^^^^ move occurs because `self.0` has type `String`, which does not implement the `Copy` trait
|
= note: `#[derive(Debug)]` triggers a move because taking references to the fields of a packed struct is undefined behaviour
= note: this error originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
```
Fixes#117406
Partially addresses #110777
Rollup of 4 pull requests
Successful merges:
- #117190 (add test for #113381)
- #117516 (add test for #113375)
- #117631 (Documentation cleanup for core::error::Request.)
- #117637 (Check binders with bound vars for global bounds that don't hold)
r? `@ghost`
`@rustbot` modify labels: rollup
Detect misparsed binop caused by missing semi
When encountering
```rust
foo()
*bar = baz;
```
We currently emit potentially two errors, one for the return type of
`foo` not being multiplicative by the type of `bar`, and another for
`foo() * bar` not being assignable.
We now check for this case and suggest adding a semicolon in the right
place and emit only a single error.
Fix#80446.
Couple of small changes
These are unrelated to each other, but they are each small enough that opening separate PR's doesn't make sense to me either.
* Remove a place where the parse driver query is stolen.
* Update an outdated doc comment
* Use correct crate name in `-Zprint-vtable-sizes` when using `#![crate_name = "..."]`.
Add FileCheck annotations to a few MIR opt tests
const_debuginfo did not specify which passes were running.
const_prop_miscompile is renamed and moved to const_prop directory.
while_storage was broken.
Stabilize `const_maybe_uninit_zeroed` and `const_mem_zeroed`
Make `MaybeUninit::zeroed` and `mem::zeroed` const stable. Newly stable API:
```rust
// core::mem
pub const unsafe fn zeroed<T>() ->;
impl<T> MaybeUninit<T> {
pub const fn zeroed() -> MaybeUninit<T>;
}
```
This relies on features based around `const_mut_refs`. Per `@RalfJung,` this should be OK since we do not leak any `&mut` to the user.
For this to be possible, intrinsics `assert_zero_valid` and `assert_mem_uninitialized_valid` were made const stable.
Tracking issue: #91850
Zulip discussion: https://rust-lang.zulipchat.com/#narrow/stream/146212-t-compiler.2Fconst-eval/topic/.60const_mut_refs.60.20dependents
r? libs-api
`@rustbot` label -T-libs +T-libs-api +A-const-eval
cc `@RalfJung` `@oli-obk` `@rust-lang/wg-const-eval`
Make sure that predicates with unmentioned bound vars are still considered global in the old solver
In the old solver, we consider predicates with late-bound vars to not be "global":
9c8a2694fa/compiler/rustc_trait_selection/src/traits/select/mod.rs (L1840-L1844)
The implementation of `has_late_bound_vars` was modified in #115834 so that we'd properly anonymize binders that had late-bound vars but didn't reference them. This fixed an ICE.
However, this also led to a behavioral change in https://github.com/rust-lang/rust/issues/117056#issuecomment-1775014545 for a couple of crates, which now consider `for<'a> GL33: Shader` (note the binder var that is *not* used in the predicate) to not be "global". This forces associated types to not be normalizable due to the old trait solver being dumb.
This PR distinguishes types which *reference* late-bound vars and binders which *have* late-bound vars. The latter is represented with the new type flag `TypeFlags::HAS_BINDER_VARS`, which is used when we only care about knowing whether binders have vars in their bound var list (even if they're not used, like for binder anonymization).
This should fix (after beta backport) the `luminance-gl` and `luminance-webgl` crates in #117056.
r? types
**(priority is kinda high on a review here given beta becomes stable on November 16.)**
Hint optimizer about try-reserved capacity
This is #116568, but limited only to the less-common `try_reserve` functions to reduce bloat in debug binaries from debug info, while still addressing the main use-case #116570
Rollup of 6 pull requests
Successful merges:
- #110340 (Deref docs: expand and remove "smart pointer" qualifier)
- #116894 (Guarantee that `char` has the same size and alignment as `u32`)
- #117534 (clarify that the str invariant is a safety, not validity, invariant)
- #117562 (triagebot no-merges: exclude different case)
- #117570 (fallback for `construct_generic_bound_failure`)
- #117583 (Remove `'tcx` lifetime on `PlaceholderConst`)
r? `@ghost`
`@rustbot` modify labels: rollup
fallback for `construct_generic_bound_failure`
Fixes#117547
This case regressed at #115882.
In this context, `generic_param_scope` is produced by `RPITVisitor` and not included by `hir_owner`. Therefore, I've added a fallback to address this.
Make `core::mem::zeroed` const stable. Newly stable API:
// core::mem
pub const unsafe fn zeroed<T>() -> T;
This is stabilized with `const_maybe_uninit_zeroed` since it is a simple
wrapper.
In order to make this possible, intrinsics `assert_zero_valid` was made
const stable under `const_assert_type2`.
`assert_mem_uninitialized_valid` was also made const stable since it is
under the same gate.
Update the alignment checks to match rust-lang/reference#1387
Previously, we had a special case to not check `Rvalue::AddressOf` in this pass because we weren't quite sure if pointers needed to be aligned in the Place passed to it: https://github.com/rust-lang/rust/pull/112026
Since https://github.com/rust-lang/reference/pull/1387 merged, this PR updates this pass to match. The behavior of the check is nearly unchanged, except we also avoid inserting a check for creating references. Most of the changes in this PR are cleanup and new tests.
Cleanup `rustc_mir_build/../check_match.rs`
The file had become pretty unwieldy, with a fair amount of duplication. As a bonus, I discovered that we weren't running some pattern checks in if-let chains.
I recommend looking commit-by-commit. The last commit is a whim, I think it makes more sense that way but I don't hold this opinion strongly.
They've been deprecated for four years.
This commit includes the following changes.
- It eliminates the `rustc_plugin_impl` crate.
- It changes the language used for lints in
`compiler/rustc_driver_impl/src/lib.rs` and
`compiler/rustc_lint/src/context.rs`. External lints are now called
"loaded" lints, rather than "plugins" to avoid confusion with the old
plugins. This only has a tiny effect on the output of `-W help`.
- E0457 and E0498 are no longer used.
- E0463 is narrowed, now only relating to unfound crates, not plugins.
- The `plugin` feature was moved from "active" to "removed".
- It removes the entire plugins chapter from the unstable book.
- It removes quite a few tests, mostly all of those in
`tests/ui-fulldeps/plugin/`.
Closes#29597.
Fix incorrect trait bound restriction suggestion
Suggest
```
error[E0308]: mismatched types
--> $DIR/restrict-assoc-type-of-generic-bound.rs:9:12
|
LL | pub fn foo<A: MyTrait, B>(a: A) -> B {
| - - expected `B` because of return type
| |
| expected this type parameter
LL | return a.bar();
| ^^^^^^^ expected type parameter `B`, found associated type
|
= note: expected type parameter `B`
found associated type `<A as MyTrait>::T`
help: consider further restricting this bound
|
LL | pub fn foo<A: MyTrait<T = B>, B>(a: A) -> B {
| +++++++
```
instead of
```
error[E0308]: mismatched types
--> $DIR/restrict-assoc-type-of-generic-bound.rs:9:12
|
LL | pub fn foo<A: MyTrait, B>(a: A) -> B {
| - - expected `B` because of return type
| |
| expected this type parameter
LL | return a.bar();
| ^^^^^^^ expected type parameter `B`, found associated type
|
= note: expected type parameter `B`
found associated type `<A as MyTrait>::T`
help: consider further restricting this bound
|
LL | pub fn foo<A: MyTrait + <T = B>, B>(a: A) -> B {
| +++++++++
```
Fix#117501.
Pretty print `Fn` traits in `rustc_on_unimplemented`
I don't think that users really ever should need to think about `Fn*` traits' tupled args for a simple trait error.
r? diagnostics
Derive expansions for packed structs cause move errors because
they prefer copying over borrowing since borrowing the fields of a
packed struct can result in unaligned access and therefore undefined
behaviour.
This underlying cause of the errors, however, is not apparent
to the user. We add a diagnostic note here to remedy that.
Add all RPITITs when augmenting param-env with GAT bounds in `check_type_bounds`
When checking that associated type definitions actually satisfy their associated type bounds in `check_type_bounds`, we construct a "`normalize_param_env`" which adds a projection predicate that allows us to assume that we can project the GAT to the definition we're checking. For example, in:
```rust
type Foo {
type Bar: Display = i32;
}
```
We would add `<Self as Foo>::Bar = i32` as a projection predicate when checking that `i32: Display` holds.
That `normalize_param_env` was, for some reason, only being used to normalize the predicate before it was registered. This is sketchy, because a nested obligation may require the GAT bound to hold, and also the projection cache is broken and doesn't differentiate projection cache keys that differ by param-envs 😿.
This `normalize_param_env` is also not sufficient when we have nested RPITITs and default trait methods, since we need to be able to assume we can normalize both the RPITIT and all of its child RPITITs to sufficiently prove all of its bounds. This is the cause of #117104, which only starts to fail for RPITITs that are nested 3 and above due to the projection-cache bug above.[^1]
## First fix
Use the `normalize_param_env` everywhere in `check_type_bounds`. This is reflected in a test I've constructed that fixes a GAT-only failure.
## Second fix
For RPITITs, install projection predicates for each RPITIT in the same function in `check_type_bounds`. This fixes#117104.
not sure who to request, so...
r? `@lcnr` hehe feel free to reassign :3
[^1]: The projection cache bug specifically occurs because we try normalizing the `assumed_wf_types` with the non-normalization param-env. This causes us to insert a projection cache entry that keeps the outermost RPITIT rigid, and it trivially satisifes all its own bounds. Super sketchy![^2]
[^2]: I haven't actually gone and fixed the projection cache bug because it's only marginally related, but I could, and it should no longer be triggered here.
Suggest
```
error[E0308]: mismatched types
--> $DIR/restrict-assoc-type-of-generic-bound.rs:9:12
|
LL | pub fn foo<A: MyTrait, B>(a: A) -> B {
| - - expected `B` because of return type
| |
| expected this type parameter
LL | return a.bar();
| ^^^^^^^ expected type parameter `B`, found associated type
|
= note: expected type parameter `B`
found associated type `<A as MyTrait>::T`
help: consider further restricting this bound
|
LL | pub fn foo<A: MyTrait<T = B>, B>(a: A) -> B {
| +++++++
```
instead of
```
error[E0308]: mismatched types
--> $DIR/restrict-assoc-type-of-generic-bound.rs:9:12
|
LL | pub fn foo<A: MyTrait, B>(a: A) -> B {
| - - expected `B` because of return type
| |
| expected this type parameter
LL | return a.bar();
| ^^^^^^^ expected type parameter `B`, found associated type
|
= note: expected type parameter `B`
found associated type `<A as MyTrait>::T`
help: consider further restricting this bound
|
LL | pub fn foo<A: MyTrait + <T = B>, B>(a: A) -> B {
| +++++++++
```
Fix#117501.
Fix order of implementations in the "implementations on foreign types" section
Fixes#117391.
We forgot to run the `sort_by_cached_key` on this section. This fixes it.
r? `@notriddle`
Remove support for alias `-Z symbol-mangling-version`
(This is very similar to the removal of `-Z instrument-coverage` in #117111.)
`-C symbol-mangling-version` was stabilized back in rustc 1.59.0 (2022-02-24) via #90128, with the old unstable flag kept around (with a warning) as an alias to ease migration.
Clarify `Unsize` documentation
The documentation erroneously says that:
```rust
/// - Types implementing a trait `Trait` also implement `Unsize<dyn Trait>`.
/// - Structs `Foo<..., T, ...>` implement `Unsize<Foo<..., U, ...>>` if all of these conditions
/// are met:
/// - `T: Unsize<U>`.
/// - Only the last field of `Foo` has a type involving `T`.
/// - `Bar<T>: Unsize<Bar<U>>`, where `Bar<T>` stands for the actual type of that last field.
```
Specifically, `T: Unsize<U>` is not required to hold -- only the final field must implement `FinalField<T>: Unsize<FinalField<U>>`. This can be demonstrated by the test I added.
---
Second commit fleshes out the documentation a lot more.
Don't check for alias bounds in liveness when aliases have escaping bound vars
I actually have no idea how we *should* be treating aliases with escaping bound vars here... but the simplest behavior is just doing what we used to do before.
r? aliemjay
Fixes#117455
Most notably, this commit changes the `pub use crate::*;` in that file
to `use crate::*;`. This requires a lot of `use` items in other crates
to be adjusted, because everything defined within `rustc_span::*` was
also available via `rustc_span::source_map::*`, which is bizarre.
The commit also removes `SourceMap::span_to_relative_line_string`, which
is unused.
Rollup of 4 pull requests
Successful merges:
- #117298 (Recover from missing param list in function definitions)
- #117373 (Avoid the path trimming ICE lint in error reporting)
- #117441 (Do not assert in op_to_const.)
- #117488 (Update minifier-rs version to 0.3.0)
r? `@ghost`
`@rustbot` modify labels: rollup
Do not assert in op_to_const.
`op_to_const` is used in `try_destructure_mir_constant_for_diagnostics`, which may encounter invalid constants created by optimizations and debugging.
r? ``@oli-obk``
Fixes https://github.com/rust-lang/rust/issues/117368
Add FileCheck annotations to MIR-opt inlining tests
Part of #116971, adds FileCheck annotations to MIR-opt tests in `tests/mir-opt/inline`.
I left out a few (such as `inline_cycle`) where it mentioned that the particular outcome of inlining isn't important, just that the inliner doesn't get stuck in an infinite loop.
r? cjgillot
Account for `ref` and `mut` in the wrong place for pattern ident renaming
If the user writes `S { ref field: name }` instead of `S { field: ref name }`, we suggest the correct code.
Fix#72298.
Support enum variants in offset_of!
This MR implements support for navigating through enum variants in `offset_of!`, placing the enum variant name in the second argument to `offset_of!`. The RFC placed it in the first argument, but I think it interacts better with nested field access in the second, as you can then write things like
```rust
offset_of!(Type, field.Variant.field)
```
Alternatively, a syntactic distinction could be made between variants and fields (e.g. `field::Variant.field`) but I'm not convinced this would be helpful.
[RFC 3308 # Enum Support](https://rust-lang.github.io/rfcs/3308-offset_of.html#enum-support-offset_ofsomeenumstructvariant-field_on_variant)
Tracking Issue #106655.
Clean up unchecked_math, separate out unchecked_shifts
Tracking issue: #85122
Changes:
1. Remove `const_inherent_unchecked_arith` flag and make const-stability flags the same as the method feature flags. Given the number of other unsafe const fns already stabilised, it makes sense to just stabilise these in const context when they're stabilised.
2. Move `unchecked_shl` and `unchecked_shr` into a separate `unchecked_shifts` flag, since the semantics for them are unclear and they'll likely be stabilised separately as a result.
3. Add an `unchecked_neg` method exclusively to signed integers, under the `unchecked_neg` flag. This is because it's a new API and probably needs some time to marinate before it's stabilised, and while it *would* make sense to have a similar version for unsigned integers since `checked_neg` also exists for those there is absolutely no case where that would be a good idea, IMQHO.
The longer-term goal here is to prepare the `unchecked_math` methods for an FCP and stabilisation since they've existed for a while, their semantics are clear, and people seem in favour of stabilising them.
Match usize/isize exhaustively with half-open ranges
The long-awaited finale to the saga of [exhaustiveness checking for integers](https://github.com/rust-lang/rust/pull/50912)!
```rust
match 0usize {
0.. => {} // exhaustive!
}
match 0usize {
0..usize::MAX => {} // helpful error message!
}
```
Features:
- Half-open ranges behave as expected for `usize`/`isize`;
- Trying to use `0..usize::MAX` will tell you that `usize::MAX..` is missing and explain why. No more unhelpful "`_` is missing";
- Everything else stays the same.
This should unblock https://github.com/rust-lang/rust/issues/37854.
Review-wise:
- I recommend looking commit-by-commit;
- This regresses perf because of the added complexity in `IntRange`; hopefully not too much;
- I measured each `#[inline]`, they all help a bit with the perf regression (tho I don't get why);
- I did not touch MIR building; I expect there's an easy PR there that would skip unnecessary comparisons when the range is half-open.
Replace switch to unreachable by assume statements
`UnreachablePropagation` currently keeps some switch terminators alive in order to ensure codegen can infer the inequalities on the discriminants.
This PR proposes to encode those inequalities as `Assume` statements.
This allows to simplify MIR further by removing some useless terminators.
Rollup of 5 pull requests
Successful merges:
- #113241 (rustdoc: Document lack of object safety on affected traits)
- #117388 (Turn const_caller_location from a query to a hook)
- #117417 (Add a stable MIR visitor)
- #117439 (prepopulate opaque ty storage before using it)
- #117451 (Add support for pre-unix-epoch file dates on Apple platforms (#108277))
r? `@ghost`
`@rustbot` modify labels: rollup
rustdoc: Document lack of object safety on affected traits
Closes#85138
I saw the issue didn't have any recent activity, if there is another MR for it I missed it.
I want the issue to move forward so here is my proposition.
It takes some space just before the "Implementors" section and only if the trait is **not** object
safe since it is the only case where special care must be taken in some cases and this has the
benefit of avoiding generation of HTML in (I hope) the common case.
Accept less invalid Rust in rustdoc
pulled out of https://github.com/rust-lang/rust/pull/117213 where this change was already approved
This only affects rustdoc, and has up to [20% perf regressions in rustdoc](https://github.com/rust-lang/rust/pull/117213#issuecomment-1785776288). These are unavoidable, as we are simply doing more checks now, but it's part of the longer term plan of making rustdoc more resistant to ICEs by only accepting valid Rust code.
Rollup of 5 pull requests
Successful merges:
- #116267 (Some codegen cleanups around SIMD checks)
- #116712 (When encountering unclosed delimiters during lexing, check for diff markers)
- #117416 (Also consider TAIT to be uncomputable if the MIR body is tainted)
- #117421 (coverage: Replace impossible `coverage::Error` with assertions)
- #117438 (Do not ICE on constant evaluation failure in GVN.)
r? `@ghost`
`@rustbot` modify labels: rollup
Also consider TAIT to be uncomputable if the MIR body is tainted
Not totally sure if this is the best solution. We could, alternatively, look at the hir typeck results and try to take a type from there instead of just falling back to type error, inferring `u8` instead of `{type error}`. Not certain it really matters, though.
Happy to iterate on this.
Fixes#117413
r? ``@oli-obk`` cc ``@Nadrieril``
Store #[deprecated] attribute's `since` value in parsed form
This PR implements the first followup bullet listed in https://github.com/rust-lang/rust/pull/117148#issue-1960240108.
We centralize error handling to the attribute parsing code in `compiler/rustc_attr/src/builtin.rs`, and thereby remove some awkward error codepaths from later phases of compilation that had to make sense of these #\[deprecated\] attributes, namely `compiler/rustc_passes/src/stability.rs` and `compiler/rustc_middle/src/middle/stability.rs`.
Detect object safety errors when assoc type is missing
When an associated type with GATs isn't specified in a `dyn Trait`, emit an object safety error instead of only complaining about the missing associated type, as it will lead the user down a path of three different errors before letting them know that what they were trying to do is impossible to begin with.
Fix#103155.
When an associated type with GATs isn't specified in a `dyn Trait`, emit
an object safety error instead of only complaining about the missing
associated type, as it will lead the user down a path of three different
errors before letting them know that what they were trying to do is
impossible to begin with.
Fix#103155.
Rollup of 7 pull requests
Successful merges:
- #116862 (Detect when trait is implemented for type and suggest importing it)
- #117389 (Some diagnostics improvements of `gen` blocks)
- #117396 (Don't treat closures/coroutine types as part of the public API)
- #117398 (Correctly handle nested or-patterns in exhaustiveness)
- #117403 (Poison check_well_formed if method receivers are invalid to prevent typeck from running on it)
- #117411 (Improve some diagnostics around `?Trait` bounds)
- #117414 (Don't normalize to an un-revealed opaque when we hit the recursion limit)
r? `@ghost`
`@rustbot` modify labels: rollup
Don't normalize to an un-revealed opaque when we hit the recursion limit
Currently, we will normalize `Opaque := Option<&Opaque>` to something like `Option<&Option<&Option<&...Opaque>>>`, hitting a limit and bottoming out in an unnormalized opaque after the recursion limit gets hit.
Unfortunately, during `layout_of`, we'll simply recurse and try again if the type normalizes to something different than the type:
e6e931dda5/compiler/rustc_ty_utils/src/layout.rs (L58-L60)
That means then we'll try to normalize `Option<&Option<&Option<&...Opaque>>>` again, substituting `Opaque` into itself even deeper. Eventually this will get to the point that we're just stack-overflowing on a really deep type before even hitting an opaque again.
To fix this, we just bottom out into `ty::Error` instead of the unrevealed opaque type.
Fixes#117412
r? `@oli-obk`
Improve some diagnostics around `?Trait` bounds
* uses better spans
* clarifies a message that was only talking about generic params, but applies to `dyn ?Trait` and `impl ?Trait` as well
Poison check_well_formed if method receivers are invalid to prevent typeck from running on it
fixes#117379
Though if some code invokes typeck without having first invoked `check_well_formed` then we'll encounter this ICE again. This can happen in const and const fn bodies if they are evaluated due to other `check_well_formed` checks or similar
Correctly handle nested or-patterns in exhaustiveness
I had assumed nested or-patterns were flattened, and they mostly are but not always.
Fixes https://github.com/rust-lang/rust/issues/117378
Fix missing leading space in suggestion
For a local pattern with no space between `let` and `(` e.g.:
```rust
let(_a) = 3;
```
we were previously suggesting this illegal code:
```rust
let_a = 3;
```
After this change the suggestion will instead be:
```rust
let _a = 3;
```
Fixes#117380
C-variadic error improvements
A couple improvements for c-variadic errors:
1. Fix the bad-c-variadic error being emitted multiple times. If a function incorrectly contains multiple `...` args, and is also not foreign or `unsafe extern "C"`, only emit the latter error once rather than once per `...`.
2. Explicitly reject `const` C-variadic functions. Trying to use C-variadics in a const function would previously fail with an error like "destructor of `VaListImpl<'_>` cannot be evaluated at compile-time". Add an explicit check for const C-variadics to provide a clearer error: "functions cannot be both `const` and C-variadic". This also addresses one of the concerns in https://github.com/rust-lang/rust/issues/44930: "Ensure that even when this gets stabilized for regular functions, it is still rejected on const fn."
On object safety error, mention new enum as alternative
When we encounter a `dyn Trait` that isn't object safe, look for its implementors. If there's one, mention using it directly If there are less than 9, mention the possibility of creating a new enum and using that instead.
Fix#80194.
rustdoc: elide cross-crate default generic arguments
Elide cross-crate generic arguments if they coincide with their default.
TL;DR: Most notably, no more `Box<…, Global>` in `std`'s docs, just `Box<…>` from now on.
Fixes#80379.
Also helps with #44306. Follow-up to #103885, #107637.
r? ``@ghost``
Trying to use C-variadics in a const function would previously fail with
an error like "destructor of `VaListImpl<'_>` cannot be evaluated at
compile-time".
Add an explicit check for const C-variadics to provide a clearer error:
"functions cannot be both `const` and C-variadic".
For a local pattern with no space between `let` and `(` e.g.:
let(_a) = 3;
we were previously suggesting this illegal code:
let_a =3;
After this change the suggestion will instead be:
let _a =3;
(Note the space after `let`)
Fail typeck for illegal break-with-value
This is fixes the issue wherein typeck was succeeding for break-with-value exprs at illegal locations such as inside `while`, `while let` and `for` loops which eventually caused an ICE during MIR interpretation for const eval.
Now we fail typeck for such code which prevents faulty MIR from being generated and interpreted, thus fixing the ICE.
Fixes#114529