It bugs me when variables of type `Ident` are called `name`. It leads to
silly things like `name.name`. `Ident` variables should be called
`ident`, and `name` should be used for variables of type `Symbol`.
This commit improves things by by doing `s/name/ident/` on a bunch of
`Ident` variables. Not all of them, but a decent chunk.
Do not visit whole crate to compute `lints_that_dont_need_to_run`.
This allows to reuse the computed lint levels instead of re-visiting the whole crate.
Add new `PatKind::Missing` variants
To avoid some ugly uses of `kw::Empty` when handling "missing" patterns, e.g. in bare fn tys. Helps with #137978. Details in the individual commits.
r? ``@oli-obk``
Move methods from `Map` to `TyCtxt`, part 5.
This eliminates all methods on `Map`. Actually removing `Map` will occur in a follow-up PR.
A follow-up to #137504.
r? `@Zalathar`
`ast::Item` has an `ident` field.
- It's always non-empty for these item kinds: `ExternCrate`, `Static`,
`Const`, `Fn`, `Mod`, `TyAlias`, `Enum`, `Struct`, `Union`,
`Trait`, `TraitAlias`, `MacroDef`, `Delegation`.
- It's always empty for these item kinds: `Use`, `ForeignMod`,
`GlobalAsm`, `Impl`, `MacCall`, `DelegationMac`.
There is a similar story for `AssocItemKind` and `ForeignItemKind`.
Some sites that handle items check for an empty ident, some don't. This
is a very C-like way of doing things, but this is Rust, we have sum
types, we can do this properly and never forget to check for the
exceptional case and never YOLO possibly empty identifiers (or possibly
dummy spans) around and hope that things will work out.
The commit is large but it's mostly obvious plumbing work. Some notable
things.
- `ast::Item` got 8 bytes bigger. This could be avoided by boxing the
fields within some of the `ast::ItemKind` variants (specifically:
`Struct`, `Union`, `Enum`). I might do that in a follow-up; this
commit is big enough already.
- For the visitors: `FnKind` no longer needs an `ident` field because
the `Fn` within how has one.
- In the parser, the `ItemInfo` typedef is no longer needed. It was used
in various places to return an `Ident` alongside an `ItemKind`, but
now the `Ident` (if present) is within the `ItemKind`.
- In a few places I renamed identifier variables called `name` (or
`foo_name`) as `ident` (or `foo_ident`), to better match the type, and
because `name` is normally used for `Symbol`s. It's confusing to see
something like `foo_name.name`.
[AIX] Ignore linting on repr(C) structs with repr(packed) or repr(align(n))
This PR updates the lint added in 9b40bd7 to ignore repr(C) structs that also have repr(packed) or repr(align(n)).
As these representations can be modifiers on repr(C), it is assumed that users that add these should know what they are doing, and thus the the lint should not warn on the respective structs. For example, for the time being, using repr(packed) and manually padding a repr(C) struct can be done to correctly align struct members on AIX.
"Missing" patterns are possible in bare fn types (`fn f(u32)`) and
similar places. Currently these are represented in the AST with
`ast::PatKind::Ident` with no `by_ref`, no `mut`, an empty ident, and no
sub-pattern. This flows through to `{hir,thir}::PatKind::Binding` for
HIR and THIR.
This is a bit nasty. It's very non-obvious, and easy to forget to check
for the exceptional empty identifier case.
This commit adds a new variant, `PatKind::Missing`, to do it properly.
The process I followed:
- Add a `Missing` variant to `{ast,hir,thir}::PatKind`.
- Chang `parse_param_general` to produce `ast::PatKind::Missing`
instead of `ast::PatKind::Missing`.
- Look through `kw::Empty` occurrences to find functions where an
existing empty ident check needs replacing with a `PatKind::Missing`
check: `print_param`, `check_trait_item`, `is_named_param`.
- Add a `PatKind::Missing => unreachable!(),` arm to every exhaustive
match identified by the compiler.
- Find which arms are actually reachable by running the test suite,
changing them to something appropriate, usually by looking at what
would happen to a `PatKind::Ident`/`PatKind::Binding` with no ref, no
`mut`, an empty ident, and no subpattern.
Quite a few of the `unreachable!()` arms were never reached. This makes
sense because `PatKind::Missing` can't happen in every pattern, only
in places like bare fn tys and trait fn decls.
I also tried an alternative approach: modifying `ast::Param::pat` to
hold an `Option<P<Pat>>` instead of a `P<Pat>`, but that quickly turned
into a very large and painful change. Adding `PatKind::Missing` is much
easier.
Implement lint against using Interner and InferCtxtLike in random compiler crates
Often `Interner` defines similar methods to `TyCtxt` (but often simplified due to the simpler API surface of the type system layer for the new solver), which people will either unintentionally or intentionally import and use. Let's discourage that.
r? lcnr
Visitors track whether an assoc item is in a trait impl or an inherent impl
`AssocCtxt::Impl` now contains an `of_trait` field. This allows ast lowering and nameres to not have to track whether we're in a trait impl or an inherent impl.
Use `Option<Ident>` for lowered param names.
Parameter patterns are lowered to an `Ident` by `lower_fn_params_to_names`, which is used when lowering bare function types, trait methods, and foreign functions. Currently, there are two exceptional cases where the lowered param can become an empty `Ident`.
- If the incoming pattern is an empty `Ident`. This occurs if the parameter is anonymous, e.g. in a bare function type.
- If the incoming pattern is neither an ident nor an underscore. Any such parameter will have triggered a compile error (hence the `span_delayed_bug`), but lowering still occurs.
This commit replaces these empty `Ident` results with `None`, which eliminates a number of `kw::Empty` uses, and makes it impossible to fail to check for these exceptional cases.
Note: the `FIXME` comment in `is_unwrap_or_empty_symbol` is removed. It actually should have been removed in #138482, the precursor to this PR. That PR changed the lowering of wild patterns to `_` symbols instead of empty symbols, which made the mentioned underscore check load-bearing.
r? ``@compiler-errors``
mir_build: consider privacy when checking for irrefutable patterns
This PR fixes#137999.
Note that, since this makes the compiler reject code that was previously accepted, it will probably need a crater run.
I include a commit that factors out a common code pattern into a helper function, purely because the fact that this was repeated all over the place was bothering me. Let me know if I should split that into a separate PR instead.
Parameter patterns are lowered to an `Ident` by
`lower_fn_params_to_names`, which is used when lowering bare function
types, trait methods, and foreign functions. Currently, there are two
exceptional cases where the lowered param can become an empty `Ident`.
- If the incoming pattern is an empty `Ident`. This occurs if the
parameter is anonymous, e.g. in a bare function type.
- If the incoming pattern is neither an ident nor an underscore. Any
such parameter will have triggered a compile error (hence the
`span_delayed_bug`), but lowering still occurs.
This commit replaces these empty `Ident` results with `None`, which
eliminates a number of `kw::Empty` uses, and makes it impossible to fail
to check for these exceptional cases.
Note: the `FIXME` comment in `is_unwrap_or_empty_symbol` is removed. It
actually should have been removed in #138482, the precursor to this PR.
That PR changed the lowering of wild patterns to `_` symbols instead of
empty symbols, which made the mentioned underscore check load-bearing.
`hir::Item` has an `ident` field.
- It's always non-empty for these item kinds: `ExternCrate`, `Static`,
`Const`, `Fn`, `Macro`, `Mod`, `TyAlias`, `Enum`, `Struct`, `Union`,
Trait`, TraitAalis`.
- It's always empty for these item kinds: `ForeignMod`, `GlobalAsm`,
`Impl`.
- For `Use`, it is non-empty for `UseKind::Single` and empty for
`UseKind::{Glob,ListStem}`.
All of this is quite non-obvious; the only documentation is a single
comment saying "The name might be a dummy name in case of anonymous
items". Some sites that handle items check for an empty ident, some
don't. This is a very C-like way of doing things, but this is Rust, we
have sum types, we can do this properly and never forget to check for
the exceptional case and never YOLO possibly empty identifiers (or
possibly dummy spans) around and hope that things will work out.
The commit is large but it's mostly obvious plumbing work. Some notable
things.
- A similar transformation makes sense for `ast::Item`, but this is
already a big change. That can be done later.
- Lots of assertions are added to item lowering to ensure that
identifiers are empty/non-empty as expected. These will be removable
when `ast::Item` is done later.
- `ItemKind::Use` doesn't get an `Ident`, but `UseKind::Single` does.
- `lower_use_tree` is significantly simpler. No more confusing `&mut
Ident` to deal with.
- `ItemKind::ident` is a new method, it returns an `Option<Ident>`. It's
used with `unwrap` in a few places; sometimes it's hard to tell
exactly which item kinds might occur. None of these unwraps fail on
the test suite. It's conceivable that some might fail on alternative
input. We can deal with those if/when they happen.
- In `trait_path` the `find_map`/`if let` is replaced with a loop, and
things end up much clearer that way.
- `named_span` no longer checks for an empty name; instead the call site
now checks for a missing identifier if necessary.
- `maybe_inline_local` doesn't need the `glob` argument, it can be
computed in-function from the `renamed` argument.
- `arbitrary_source_item_ordering::check_mod` had a big `if` statement
that was just getting the ident from the item kinds that had one. It
could be mostly replaced by a single call to the new `ItemKind::ident`
method.
- `ItemKind` grows from 56 to 64 bytes, but `Item` stays the same size,
and that's what matters, because `ItemKind` only occurs within `Item`.
Refactor is_snake_case.
I wondered what the definition of this actually was, and found the original hard to read. I believe this change preserves the original behavior, but is hopefully clearer.
Visit `PatField` when collecting lint levels
Fixes#138428
Side-note, I vaguely skimmed over the other nodes we could be visiting here and it doesn't *seem* to me that we're missing anything, though I may be mistaken given recent(?) support for attrs in where clauses(??). Can be fixed in a follow-up PR.
Fix false-positive in `expr_or_init` and in the `invalid_from_utf8` lint
This PR fixes the logic for finding initializer in the `expr_or_init` and `expr_or_init_with_outside_body` functions.
If the binding were to be mutable (`let mut`), the logic wouldn't consider that the initializer expression could have been modified and would return the init expression even-trough multiple subsequent assignments could have been done.
Example:
```rust
let mut a = [99, 108, 130, 105, 112, 112]; // invalid, not UTF-8
loop {
a = *b"clippy"; // valid
break;
}
std::str::from_utf8_mut(&mut a); // currently warns, with this PR it doesn't
```
This PR modifies the logic to excludes mutable let bindings.
Found when using `expr_or_init` in https://github.com/rust-lang/rust/pull/119220.
r? compiler
Continuing the work from #137350.
Removes the unused methods: `expect_variant`, `expect_field`,
`expect_foreign_item`.
Every method gains a `hir_` prefix.
To make room for the moving of `Map::attrs` to `TyCtxt::hir_attrs` in
the next commit. (It makes sense to rename the query, because it has
many fewer uses than the method.)
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.
This PR updates the lint added in 9b40bd7 to ignore repr(C) structs that also
have repr(packed) or repr(align(n)).
As these representations can be modifiers on repr(C), it is assumed that users
that add these should know what they are doing, and thus the the lint should not
warn on the respective structs. For example, for the time being, using
repr(packed) and manually padding a repr(C) struct can be done to correctly
align struct members on AIX.
A check for `#[non_exhaustive]` is often done in combination with
checking whether the type is local to the crate, in a variety of ways.
Create a helper method and standardize on it as the way to check for
this.
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``
