Add `#[define_opaques]` attribute and require it for all type-alias-impl-trait sites that register a hidden type
Instead of relying on the signature of items to decide whether they are constraining an opaque type, the opaque types that the item constrains must be explicitly listed.
A previous version of this PR used an actual attribute, but had to keep the resolved `DefId`s in a side table.
Now we just lower to fields in the AST that have no surface syntax, instead a builtin attribute macro fills in those fields where applicable.
Note that for convenience referencing opaque types in associated types from associated methods on the same impl will not require an attribute. If that causes problems `#[defines()]` can be used to overwrite the default of searching for opaques in the signature.
One wart of this design is that closures and static items do not have generics. So since I stored the opaques in the generics of functions, consts and methods, I would need to add a custom field to closures and statics to track this information. During a T-types discussion we decided to just not do this for now.
fixes#131298
Revert <https://github.com/rust-lang/rust/pull/138084> to buy time to
consider options that avoids breaking downstream usages of cargo on
distributed `rustc-src` artifacts, where such cargo invocations fail due
to inability to inherit `lints` from workspace root manifest's
`workspace.lints` (this is only valid for the source rust-lang/rust
workspace, but not really the distributed `rustc-src` artifacts).
This breakage was reported in
<https://github.com/rust-lang/rust/issues/138304>.
This reverts commit 48caf81484, reversing
changes made to c6662879b2.
By naming them in `[workspace.lints.rust]` in the top-level
`Cargo.toml`, and then making all `compiler/` crates inherit them with
`[lints] workspace = true`. (I omitted `rustc_codegen_{cranelift,gcc}`,
because they're a bit different.)
The advantages of this over the current approach:
- It uses a standard Cargo feature, rather than special handling in
bootstrap. So, easier to understand, and less likely to get
accidentally broken in the future.
- It works for proc macro crates.
It's a shame it doesn't work for rustc-specific lints, as the comments
explain.
In `walk_item`, we call `visit_id` on every item kind. For most of them
we do it directly in `walk_item`. But for `ItemKind::Mod`,
`ItemKind::Enum`, and `ItemKind::Use` we instead do it in the `walk_*`
function called (via the `visit_*` function) from `walk_item`.
I can see no reason for this inconsistency, so this commit makes those
three cases like all the other cases, moving the `visit_id` calls into
`walk_item`. This also avoids the need for a few `HirId` arguments.
compiler: add `ExternAbi::is_rustic_abi`
Various parts of the compiler were hand-rolling this extremely simple check that is nonetheless easy to get wrong as the compiler evolves over time. Discourage them from being so "original" again by replacing it with a single implementation on the type that represents these ABIs. This simplifies a surprising amount of code as a result.
Also fixes#132981, an ICE that emerged due to other checks being made stricter.
Make `ptr_cast_add_auto_to_object` lint into hard error
In Rust 1.81, we added a FCW lint (including linting in dependencies) against pointer casts that add an auto trait to dyn bounds. This was part of work making casts of pointers involving trait objects stricter, and was part of the work needed to restabilize trait upcasting.
We considered just making this a hard error, but opted against it at that time due to breakage found by crater. This breakage was mostly due to the `anymap` crate which has been a persistent problem for us.
It's now a year later, and the fact that this is not yet a hard error is giving us pause about stabilizing arbitrary self types and `derive(CoercePointee)`. So let's see about making a hard error of this.
r? ghost
cc ```@adetaylor``` ```@Darksonn``` ```@BoxyUwU``` ```@RalfJung``` ```@compiler-errors``` ```@oli-obk``` ```@WaffleLapkin```
Related:
- https://github.com/rust-lang/rust/pull/135881
- https://github.com/rust-lang/rust/issues/136702
- https://github.com/rust-lang/rust/pull/136776
Tracking:
- https://github.com/rust-lang/rust/issues/127323
- https://github.com/rust-lang/rust/issues/44874
- https://github.com/rust-lang/rust/issues/123430
fix: overflowing bin hex
**Overview:**
- This PR fixes#135404.
**Testing**
- Tested the updated functionality.
- previously emitted diagnostics:
```bash
error: literal out of range for `i32`
--> src/main.rs:2:9
|
2 | _ = 0x8FFF_FFFF_FFFF_FFFE;
| ^^^^^^^^^^^^^^^^^^^^^
|
= note: the literal `0x8FFF_FFFF_FFFF_FFFE` (decimal `10376293541461622782`) does not fit into the type `i32` and will become `-2i32`
= help: consider using the type `i128` instead
= note: `#[deny(overflowing_literals)]` on by default
help: to use as a negative number (decimal `-2`), consider using the type `u32` for the literal and cast it to `i32`
|
2 | _ = 0x8FFF_FFFF_FFFF_FFFEu32 as i32;
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
```
- current diagnostics:
```bash
error: literal out of range for `i32`
--> ../temp.rs:2:13
|
2 | let x = 0x8FFF_FFFF_FFFF_FFFE;
| ^^^^^^^^^^^^^^^^^^^^^
|
= note: the literal `0x8FFF_FFFF_FFFF_FFFE` (decimal `10376293541461622782`) does not fit into the type `i32` and will become `-2i32`
= help: consider using the type `u64` instead
= note: `#[deny(overflowing_literals)]` on by default
help: to use as a negative number (decimal `-2`), consider using the type `u64` for the literal and cast it to `i32`
|
2 | let x = 0x8FFF_FFFF_FFFF_FFFEu64 as i32;
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
```
Improve behavior of `IF_LET_RESCOPE` around temporaries and place expressions
Heavily reworks the `IF_LET_RESCOPE` to be more sensitive around 1. temporaries that get consumed/terminated and therefore should not trigger the lint, and 2. borrows of place expressions, which are not temporary values.
Fixes#137411
Greatly simplify lifetime captures in edition 2024
Remove most of the `+ Captures` and `+ '_` from the compiler, since they are now unnecessary with the new edition 2021 lifetime capture rules. Use some `+ 'tcx` and `+ 'static` rather than being overly verbose with precise capturing syntax.
Give `global_asm` a fake body to store typeck results, represent `sym fn` as a hir expr to fix `sym fn` operands with lifetimes
There are a few intertwined problems with `sym fn` operands in both inline and global asm macros.
Specifically, unlike other anon consts, they may evaluate to a type with free regions in them without actually having an item-level type annotation to give them a "proper" type. This is in contrast to named constants, which always have an item-level type annotation, or unnamed constants which are constrained by their position (e.g. a const arg in a turbofish, or a const array length).
Today, we infer the type of the operand by looking at the HIR typeck results; however, those results are region-erased, so during borrowck we ICE since we don't expect to encounter erased regions. We can't just fill this type with something like `'static`, since we may want to use real (free) regions:
```rust
fn foo<'a>() {
asm!("/* ... */", sym bar::<&'a ()>);
}
```
The first idea may be to represent `sym fn` operands using *inline* consts instead of anon consts. This makes sense, since inline consts can reference regions from the parent body (like the `'a` in the example above). However, this introduces a problem with `global_asm!`, which doesn't *have* a parent body; inline consts *must* be associated with a parent body since they are not a body owner of their own. In #116087, I attempted to fix this by using two separate `sym` operands for global and inline asm. However, this led to a lot of confusion and also some unattractive code duplication.
In this PR, I adjust the lowering of `global_asm!` so that it's lowered in a "fake" HIR body. This body contains a single expression which is `ExprKind::InlineAsm`; we don't *use* this HIR body, but it's used in typeck and borrowck so that we can properly infer and validate the the lifetimes of `sym fn` operands.
I then adjust the lowering of `sym fn` to instead be represented with a HIR expression. This is both because it's no longer necessary to represent this operand as an anon const, since it's *just* a path expression, and also more importantly to sidestep yet another ICE (https://github.com/rust-lang/rust/issues/137179), which has to do with the existing code breaking an invariant of def-id creation and anon consts. Specifically, we are not allowed to synthesize a def-id for an anon const when that anon const contains expressions with def-ids whose parent is *not* that anon const. This is somewhat related to https://github.com/rust-lang/rust/pull/130443#issuecomment-2445678945, which is also a place in the compiler where synthesizing anon consts leads to def-id parenting issue.
As a side-effect, this consolidates the type checking for inline and global asm, so it allows us to simplify `InlineAsmCtxt` a bit. It also allows us to delete a bit of hacky code from anon const `type_of` which was there to detect `sym fn` operands specifically. This also could be generalized to support `const` asm operands with types with lifetimes in them. Since we specifically reject these consts today, I'm not going to change the representation of those consts (but they'd just be turned into inline consts).
r? oli-obk -- mostly b/c you're patient and also understand the breadth of the code that this touches, please reassign if you don't want to review this.
Fixes#111709Fixes#96304Fixes#137179
In Rust 1.81, we added a FCW lint (including linting in dependencies)
against pointer casts that add an auto trait to dyn bounds. This was
part of work making casts of pointers involving trait objects stricter
which was needed to restabilize trait upcasting.
We considered just making this a hard error at the time, but opted
against it due to breakage found by crater. This breakage was mostly
due to the `anymap` crate which has been a persistent problem for us.
It's now a year later, and the fact that this is not yet a hard error
is giving us pause about stabilizing arbitrary self types and
`derive(CoercePointee)`. So let's now make a hard error of this.
Use `edition = "2024"` in the compiler (redux)
Most of this is binding mode changes, which I fixed by running `x.py fix`.
Also adds some miscellaneous `unsafe` blocks for new unsafe standard library functions (the setenv ones), and a missing `unsafe extern` block in some enzyme codegen code, and fixes some precise capturing lifetime changes (but only when they led to errors).
cc ``@ehuss`` ``@traviscross``
Specify scope in `out_of_scope_macro_calls` lint
```
warning: cannot find macro `in_root` in the crate root
--> $DIR/key-value-expansion-scope.rs:1:10
|
LL | #![doc = in_root!()]
| ^^^^^^^ not found in the crate root
|
= warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
= note: for more information, see issue #124535 <https://github.com/rust-lang/rust/issues/124535>
= help: import `macro_rules` with `use` to make it callable above its definition
= note: `#[warn(out_of_scope_macro_calls)]` on by default
```
r? ```@petrochenkov```
