Report an error if a lang item has the wrong number of generic arguments
This pull request fixes#83893. The issue is that the lang item code currently checks whether the lang item has the correct item kind (e.g. a `#[lang="add"]` has to be a trait), but not whether the item has the correct number of generic arguments.
This can lead to an "index out of bounds" ICE when the compiler tries to create more substitutions than there are suitable types available (if the lang item was declared with too many generic arguments).
For instance, here is a reduced ("reduced" in the sense that it does not trigger additional errors) version of the example given in #83893:
```rust
#![feature(lang_items,no_core)]
#![no_core]
#![crate_type="lib"]
#[lang = "sized"]
trait MySized {}
#[lang = "add"]
trait MyAdd<'a, T> {}
fn ice() {
let r = 5;
let a = 6;
r + a
}
```
On current nightly, this immediately causes an ICE without any warnings or errors emitted. With the changes in this PR, however, I get no ICE and two errors:
```
error[E0718]: `add` language item must be applied to a trait with 1 generic argument
--> pr-ex.rs:8:1
|
8 | #[lang = "add"]
| ^^^^^^^^^^^^^^^
9 | trait MyAdd<'a, T> {}
| ------- this trait has 2 generic arguments, not 1
error[E0369]: cannot add `{integer}` to `{integer}`
--> pr-ex.rs:14:7
|
14 | r + a
| - ^ - {integer}
| |
| {integer}
error: aborting due to 2 previous errors
Some errors have detailed explanations: E0369, E0718.
For more information about an error, try `rustc --explain E0369`.
```
Remove CrateNum parameter for queries that only work on local crate
The pervasive `CrateNum` parameter is a remnant of the multi-crate rustc idea.
Using `()` as query key in those cases avoids having to worry about the validity of the query key.
Remove support for floating-point constants in asm!
Floating-point constants aren't very useful anyways and this simplifies
the code since the type check can now be done in typeck.
cc `@rust-lang/wg-inline-asm`
r? `@nagisa`
Reachable statics have reachable initializers
Static initializer can read other statics. Initializers are evaluated at
compile time, and so their content could become inlined into another
crate. Ensure that initializers of reachable statics are also reachable.
Previously, when an item incorrectly considered to be unreachable was
reached from another crate an attempt would be made to codegen it. The
attempt could fail with an ICE (in the case MIR wasn't available to do
so) in some circumstances the attempt could also succeed resulting in
a local codegen of non-local items, including static ones.
Fixes#84455.
Fix `--remap-path-prefix` not correctly remapping `rust-src` component paths and unify handling of path mapping with virtualized paths
This PR fixes#73167 ("Binaries end up containing path to the rust-src component despite `--remap-path-prefix`") by preventing real local filesystem paths from reaching compilation output if the path is supposed to be remapped.
`RealFileName::Named` introduced in #72767 is now renamed as `LocalPath`, because this variant wraps a (most likely) valid local filesystem path.
`RealFileName::Devirtualized` is renamed as `Remapped` to be used for remapped path from a real path via `--remap-path-prefix` argument, as well as real path inferred from a virtualized (during compiler bootstrapping) `/rustc/...` path. The `local_path` field is now an `Option<PathBuf>`, as it will be set to `None` before serialisation, so it never reaches any build output. Attempting to serialise a non-`None` `local_path` will cause an assertion faliure.
When a path is remapped, a `RealFileName::Remapped` variant is created. The original path is preserved in `local_path` field and the remapped path is saved in `virtual_name` field. Previously, the `local_path` is directly modified which goes against its purpose of "suitable for reading from the file system on the local host".
`rustc_span::SourceFile`'s fields `unmapped_path` (introduced by #44940) and `name_was_remapped` (introduced by #41508 when `--remap-path-prefix` feature originally added) are removed, as these two pieces of information can be inferred from the `name` field: if it's anything other than a `FileName::Real(_)`, or if it is a `FileName::Real(RealFileName::LocalPath(_))`, then clearly `name_was_remapped` would've been false and `unmapped_path` would've been `None`. If it is a `FileName::Real(RealFileName::Remapped{local_path, virtual_name})`, then `name_was_remapped` would've been true and `unmapped_path` would've been `Some(local_path)`.
cc `@eddyb` who implemented `/rustc/...` path devirtualisation
Fix typo in report_unsed_assign
The function was called `report_unsed_assign`, which I assume is a typo, considering the rest of the file.
This replaces `report_unsed_assign` with `report_unused_assign`.
Static initializer can read other statics. Initializers are evaluated at
compile time, and so their content could become inlined into another
crate. Ensure that initializers of reachable statics are also reachable.
Previously, when an item incorrectly considered to be unreachable was
reached from another crate an attempt would be made to codegen it. The
attempt could fail with an ICE (in the case MIR wasn't available to do
so) in some circumstances the attempt could also succeed resulting in
a local codegen of non-local items, including static ones.
further split up const_fn feature flag
This continues the work on splitting up `const_fn` into separate feature flags:
* `const_fn_trait_bound` for `const fn` with trait bounds
* `const_fn_unsize` for unsizing coercions in `const fn` (looks like only `dyn` unsizing is still guarded here)
I don't know if there are even any things left that `const_fn` guards... at least libcore and liballoc do not need it any more.
`@oli-obk` are you currently able to do reviews?
Match against attribute name when validating attributes
Extract attribute name once and match it against symbols that are being
validated, instead of using `Session::check_name` for each symbol
individually.
Assume that all validated attributes are used, instead of marking them
as such, since the attribute check should be exhaustive.
Extract attribute name once and match it against symbols that are being
validated, instead of using `Session::check_name` for each symbol
individually.
Assume that all validated attributes are used, instead of marking them
as such, since the attribute check should be exhaustive.
Use AnonConst for asm! constants
This replaces the old system which used explicit promotion. See #83169 for more background.
The syntax for `const` operands is still the same as before: `const <expr>`.
Fixes#83169
Because the implementation is heavily based on inline consts, we suffer from the same issues:
- We lose the ability to use expressions derived from generics. See the deleted tests in `src/test/ui/asm/const.rs`.
- We are hitting the same ICEs as inline consts, for example #78174. It is unlikely that we will be able to stabilize this before inline consts are stabilized.
Rename `#[doc(spotlight)]` to `#[doc(notable_trait)]`
Fixes#80936.
"spotlight" is not a very specific or self-explaining name.
Additionally, the dialog that it triggers is called "Notable traits".
So, "notable trait" is a better name.
* Rename `#[doc(spotlight)]` to `#[doc(notable_trait)]`
* Rename `#![feature(doc_spotlight)]` to `#![feature(doc_notable_trait)]`
* Update documentation
* Improve documentation
r? `@Manishearth`
GenericParam does not need to be a HIR owner.
The special case is not required.
Universal impl traits design to regular generic parameters, and their content is owned by the enclosing item.
Existential (and opaque) impl traits generate their own enclosing item, and are collected through it.
implement `feature(const_generics_defaults)`
Implements const generics defaults `struct Example<const N: usize=3>`, as well as a query for getting the default of a given const-parameter's def id. There are some remaining FIXME's but they were specified as not blocking for merging this PR. This also puts the defaults behind the unstable feature gate `#![feature(const_generics_defaults)]`.
~~This currently creates a field which is always false on `GenericParamDefKind` for future use when
consts are permitted to have defaults. I'm not sure if this is exactly what is best for adding default parameters, but I mimicked the style of type defaults, so hopefully this is ok.~~
r? `@lcnr`
Only enable assert_dep_graph when query-dep-graph is enabled.
This is a debugging option. The only effect should be on rustc tests.
r? ``@michaelwoerister``
Replace closures_captures and upvar_capture with closure_min_captures
Removed all uses of closures_captures and upvar_capture and refactored code to work with closure_min_captures. This also involved removing functions that were no longer needed like the bridge.
Closes https://github.com/rust-lang/project-rfc-2229/issues/18
r? `@nikomatsakis`
rustdoc: allow list syntax for #[doc(alias)] attributes
Fixes https://github.com/rust-lang/rust/issues/81205.
It now allows to have:
```rust
#[doc(alias = "x")]
// and:
#[doc(alias("y", "z"))]
```
cc ``@jplatte``
r? ``@jyn514``
make changes to liveness to use closure_min_captures
use different span
borrow check uses new structures
rename to CapturedPlace
stop using upvar_capture in regionck
remove the bridge
cleanup from rebase + remove the upvar_capture reference from mutability_errors.rs
remove line from livenes test
make our unused var checking more consistent
update tests
adding more warnings to the tests
move is_ancestor_or_same_capture to rustc_middle/ty
update names to reflect the closures
add FIXME
check that all captures are immutable borrows before returning
add surrounding if statement like the original
move var out of the loop and rename
Co-authored-by: Logan Mosier <logmosier@gmail.com>
Co-authored-by: Roxane Fruytier <roxane.fruytier@hotmail.com>
StructField -> FieldDef ("field definition")
Field -> ExprField ("expression field", not "field expression")
FieldPat -> PatField ("pattern field", not "field pattern")
Also rename visiting and other methods working on them.
"spotlight" is not a very specific or self-explaining name.
Additionally, the dialog that it triggers is called "Notable traits".
So, "notable trait" is a better name.
* Rename `#[doc(spotlight)]` to `#[doc(notable_trait)]`
* Rename `#![feature(doc_spotlight)]` to `#![feature(doc_notable_trait)]`
* Update documentation
* Improve documentation
Find more invalid doc attributes
- Lint on `#[doc(123)]`, `#[doc("hello")]`, etc.
- Lint every attribute; e.g., will now report two warnings for `#[doc(foo, bar)]`
- Add hyphen to "crate level"
- Display paths like `#[doc(foo::bar)]` correctly instead of as an empty string
This change makes it easier to follow the control flow.
I also moved the end-of-line comments attached to some symbols to before
the symbol listing. This allows rustfmt to format the code; otherwise no
formatting occurs (see rust-lang/rustfmt#4750).
Cleanup rustdoc warnings
## Clean up error reporting for deprecated passes
Using `error!` here goes all the way back to the original commit, https://github.com/rust-lang/rust/pull/8540. I don't see any reason to use logging; rustdoc should use diagnostics wherever possible. See https://github.com/rust-lang/rust/pull/81932#issuecomment-785291244 for further context.
- Use spans for deprecated attributes
- Use a proper diagnostic for unknown passes, instead of error logging
- Add tests for unknown passes
- Improve some wording in diagnostics
## Report that `doc(plugins)` doesn't work using diagnostics instead of `eprintln!`
This also adds a test for the output.
This was added in https://github.com/rust-lang/rust/pull/52194. I don't see any particular reason not to use diagnostics here, I think it was just missed in https://github.com/rust-lang/rust/pull/50541.
Warn on `#![doc(test(...))]` on items other than the crate root and use future incompatible lint
Part of #82672.
This PR does multiple things:
* Create a new `INVALID_DOC_ATTRIBUTE` lint which is also "future incompatible", allowing us to use it as a warning for the moment until it turns (eventually) into a hard error.
* Use this link when `#![doc(test(...))]` isn't used at the crate level.
* Make #82702 use this new lint as well.
r? ``@jyn514``
Inherit `#[stable(..)]` annotations in enum variants and fields from its item
Lint changes for #65515. The stdlib will have to be updated once this lands in beta and that version is promoted in master.
Add #[rustc_legacy_const_generics]
This is the first step towards removing `#[rustc_args_required_const]`: a new attribute is added which rewrites function calls of the form `func(a, b, c)` to `func::<{b}>(a, c)`. This allows previously stabilized functions in `stdarch` which use `rustc_args_required_const` to use const generics instead.
This new attribute is not intended to ever be stabilized, it is only intended for use in `stdarch` as a replacement for `#[rustc_args_required_const]`.
```rust
#[rustc_legacy_const_generics(1)]
pub fn foo<const Y: usize>(x: usize, z: usize) -> [usize; 3] {
[x, Y, z]
}
fn main() {
assert_eq!(foo(0 + 0, 1 + 1, 2 + 2), [0, 2, 4]);
assert_eq!(foo::<{1 + 1}>(0 + 0, 2 + 2), [0, 2, 4]);
}
```
r? `@oli-obk`
Consider auto derefs before warning about write only fields
Changes from #81473 extended the dead code lint with an ability to detect
fields that are written to but never read from. The implementation skips
over fields on the left hand side of an assignment, without marking them
as live.
A field access might involve an automatic dereference and de-facto read
the field. Conservatively mark expressions with deref adjustments as
live to avoid generating false positive warnings.
Closes#81626.
Implement -Z hir-stats for nested foreign items
An attempt to compute HIR stats for crates with nested foreign items results in an ICE.
```rust
fn main() {
extern "C" { fn f(); }
}
```
```
thread 'rustc' panicked at 'visit_nested_xxx must be manually implemented in this visitor'
```
Provide required implementation of visitor method.
ast: Keep expansion status for out-of-line module items
I.e. whether a module `mod foo;` is already loaded from a file or not.
This is a pre-requisite to correctly treating inner attributes on such modules (https://github.com/rust-lang/rust/issues/81661).
With this change AST structures for `mod` items diverge even more for AST structure for the crate root, which previously used `ast::Mod`.
Therefore this PR removes `ast::Mod` from `ast::Crate` in the first commit, these two things are sufficiently different from each other, at least at syntactic level.
Customization points for visiting a "`mod` item or crate root" were also removed from AST visitors (`fn visit_mod`).
`ast::Mod` itself was refactored away in the second commit in favor of `ItemKind::Mod(Unsafe, ModKind)`.
Changes from 81473 extended the dead code lint with an ability to detect
fields that are written to but never read from. The implementation skips
over fields on the left hand side of an assignment, without marking them
as live.
A field access might involve an automatic dereference and de-facto read
the field. Conservatively mark expressions with deref adjustments as
live to avoid generating false positive warnings.
Print -Ztime-passes (and misc stats/logs) on stderr, not stdout.
I've tried not to change anything that looked similar to `rustc --print`, where people might use automation, and/or any "bulk" prints, such as dumping an entire Graphviz (`dot`) graph on stdout.
The reason I want `-Ztime-passes` to be on stderr like debug logging is I can get a complete (and correctly interleaved) view just by looking at stderr, which is merely a convenience when running `rustc`/Cargo directly, but even more important when it's nested in a build script, as Cargo will split the build script output into stdout (named `output`) and `stderr`.
Crate root is sufficiently different from `mod` items, at least at syntactic level.
Also remove customization point for "`mod` item or crate root" from AST visitors.
An attempt to compute HIR stats for crates with nested foreign items results in an ICE.
```
fn main() {
extern "C" { fn f(); }
}
```
```
thread 'rustc' panicked at 'visit_nested_xxx must be manually implemented in this visitor'
```
Provide required implementation of visitor method.
Visit more targets when validating attributes
This begins to address #80048, allowing for additional validation of attributes.
There are more refactorings that can be done, though I think they should be tackled in additional PRs:
* ICE when a builtin attribute is encountered that is not checked
* Move some of the attr checking done `ast_validation` into `rustc_passes`
* note that this requires a bit of additional refactoring, especially of extern items which currently parse attributes (and thus are a part of the AST) but do not possess attributes in their HIR representation.
* Rename `Target` to `AttributeTarget`
* Refactor attribute validation completely to go through `Visitor::visit_attribute`.
* This would require at a minimum passing `Target` into this method which might be too big of a refactoring to be worth it.
* It's also likely not possible to do all the validation this way as some validation requires knowing what other attributes a target has.
r? `@davidtwco`
This renames the variants in HIR UnOp from
enum UnOp {
UnDeref,
UnNot,
UnNeg,
}
to
enum UnOp {
Deref,
Not,
Neg,
}
Motivations:
- This is more consistent with the rest of the code base where most enum
variants don't have a prefix.
- These variants are never used without the `UnOp` prefix so the extra
`Un` prefix doesn't help with readability. E.g. we don't have any
`UnDeref`s in the code, we only have `UnOp::UnDeref`.
- MIR `UnOp` type variants don't have a prefix so this is more
consistent with MIR types.
- "un" prefix reads like "inverse" or "reverse", so as a beginner in
rustc code base when I see "UnDeref" what comes to my mind is
something like "&*" instead of just "*".
Add visitors for checking #[inline]
Add visitors for checking #[inline] with struct field
Fix test for #[inline]
Add visitors for checking #[inline] with #[macro_export] macro
Add visitors for checking #[inline] without #[macro_export] macro
Add use alias with Visitor
Fix lint error
Reduce unnecessary variable
Co-authored-by: LingMan <LingMan@users.noreply.github.com>
Change error to warning
Add warning for checking field, arm with #[allow_internal_unstable]
Add name resolver
Formatting
Formatting
Fix error fixture
Add checking field, arm, macro def
Refractor a few more types to `rustc_type_ir`
In the continuation of #79169, ~~blocked on that PR~~.
This PR:
- moves `IntVarValue`, `FloatVarValue`, `InferTy` (and friends) and `Variance`
- creates the `IntTy`, `UintTy` and `FloatTy` enums in `rustc_type_ir`, based on their `ast` and `chalk_ir` equilavents, and uses them for types in the rest of the compiler.
~~I will split up that commit to make this easier to review and to have a better commit history.~~
EDIT: done, I split the PR in commits of 200-ish lines each
r? `````@nikomatsakis````` cc `````@jackh726`````
Do not mark unit variants as used when in path pattern
Record that we are processing a pattern so that code responsible for
handling path resolution can correctly decide whether to mark it as
used or not.
Closes#76788.
Separate out a `hir::Impl` struct
This makes it possible to pass the `Impl` directly to functions, instead
of having to pass each of the many fields one at a time. It also
simplifies matches in many cases.
See `rustc_save_analysis::dump_visitor::process_impl` or `rustdoc::clean::clean_impl` for a good example of how this makes `impl`s easier to work with.
r? `@petrochenkov` maybe?
This makes it possible to pass the `Impl` directly to functions, instead
of having to pass each of the many fields one at a time. It also
simplifies matches in many cases.
passes: prohibit invalid attrs on generic params
Fixes#78957.
This PR modifies the `check_attr` pass so that attribute placement on generic parameters is checked for validity.
r? `@lcnr`
Allow `since="TBD"` for rustc_deprecated
Closes#78381.
This PR only affects `#[rustc_deprecated]`, not `#[deprecated]`, so there is no effect on any stable language feature.
Likewise this PR only implements `since="TBD"`, it does not actually tag any library functions with it, so there is no effect on any stable API.
Overview of changes:
* `rustc_middle/stability.rs`:
* change `deprecation_in_effect` function to return `false` when `since="TBD"`
* tidy up the compiler output when a deprecated item has `since="TBD"`
* `rustc_passes/stability.rs`:
* allow `since="TBD"` to pass the sanity check for stable_version < deprecated_version
* refactor the "invalid stability version" and "invalid deprecation version" error into separate errors
* rustdoc: make `since="TBD"` message on a deprecated item's page match the command-line deprecation output
* tests:
* test rustdoc output
* test that the `deprecated_in_future` lint fires when `since="TBD"`
* test the new "invalid deprecation version" error message
Implement if-let match guards
Implements rust-lang/rfcs#2294 (tracking issue: #51114).
I probably should do a few more things before this can be merged:
- [x] Add tests (added basic tests, more advanced tests could be done in the future?)
- [x] Add lint for exhaustive if-let guard (comparable to normal if-let statements)
- [x] Fix clippy
However since this is a nightly feature maybe it's fine to land this and do those steps in follow-up PRs.
Thanks a lot `@matthewjasper` ❤️ for helping me with lowering to MIR! Would you be interested in reviewing this?
r? `@ghost` for now
Simplify visit_{foreign,trait}_item
Using an `if` seems like a better semantic fit and saves a few lines.
Noticed while looking at https://github.com/rust-lang/rust/pull/79752, but that's already merged.
r? `@lcnr,` cc `@cjgillot`
`@rustbot` modify labels +C-cleanup +T-compiler
Compress RWU from at least 32 bits to 4 bits
The liveness uses a mixed representation of RWUs based on the
observation that most of them have invalid reader and invalid
writer. The packed variant uses 32 bits and unpacked 96 bits.
Unpacked data contains reader live node and writer live node.
Since live nodes are used only to determine their validity,
RWUs can always be stored in a packed form with four bits for
each: reader bit, writer bit, used bit, and one extra padding
bit to simplify packing and unpacking operations.
The liveness uses a mixed representation of RWUs based on the
observation that most of them have invalid reader and invalid
writer. The packed variant uses 32 bits and unpacked 96 bits.
Unpacked data contains reader live node and writer live node.
Since live nodes are used only to determine their validity,
RWUs can always be stored in a packed form with four bits for
each: reader bit, writer bit, used bit, and one extra padding
bit to simplify packing and unpacking operations.
This commit modifies the `check_attr` pass so that attribute placement
on generic parameters is checked for validity.
Signed-off-by: David Wood <david@davidtw.co>
* Reject use of parameters inside naked function body.
* Reject use of patterns inside function parameters, to emphasize role
of parameters a signature declaration (mirroring existing behaviour
for function declarations) and avoid generating code introducing
specified bindings.
RFC-2229: Implement Precise Capture Analysis
### This PR introduces
- Feature gate for RFC-2229 (incomplete) `capture_disjoint_field`
- Rustc Attribute to print out the capture analysis `rustc_capture_analysis`
- Precise capture analysis
### Description of the analysis
1. If the feature gate is not set then all variables that are not local to the closure will be added to the list of captures. (This is for backcompat)
2. The rest of the analysis is based entirely on how the captured `Place`s are used within the closure. Precise information (i.e. projections) about the `Place` is maintained throughout.
3. To reduce the amount of information we need to keep track of, we do a minimization step. In this step, we determine a list such that no Place within this list represents an ancestor path to another entry in the list. Check rust-lang/project-rfc-2229#9 for more detailed examples.
4. To keep the compiler functional as before we implement a Bridge between the results of this new analysis to existing data structures used for closure captures. Note the new capture analysis results are only part of MaybeTypeckTables that is the information is only available during typeck-ing.
### Known issues
- Statements like `let _ = x` will make the compiler ICE when used within a closure with the feature enabled. More generally speaking the issue is caused by `let` statements that create no bindings and are init'ed using a Place expression.
### Testing
We removed the code that would handle the case where the feature gate is not set, to enable the feature as default and did a bors try and perf run. More information here: #78762
### Thanks
This has been slowly in the works for a while now.
I want to call out `@Azhng` `@ChrisPardy` `@null-sleep` `@jenniferwills` `@logmosier` `@roxelo` for working on this and the previous PRs that led up to this, `@nikomatsakis` for guiding us.
Closesrust-lang/project-rfc-2229#7Closesrust-lang/project-rfc-2229#9Closesrust-lang/project-rfc-2229#6Closesrust-lang/project-rfc-2229#19
r? `@nikomatsakis`
Allow making `RUSTC_BOOTSTRAP` conditional on the crate name
Motivation: This came up in the [Zulip stream](https://rust-lang.zulipchat.com/#narrow/stream/233931-t-compiler.2Fmajor-changes/topic/Require.20users.20to.20confirm.20they.20know.20RUSTC_.E2.80.A6.20compiler-team.23350/near/208403962) for https://github.com/rust-lang/compiler-team/issues/350.
See also https://github.com/rust-lang/cargo/pull/6608#issuecomment-458546258; this implements https://github.com/rust-lang/cargo/issues/6627.
The goal is for this to eventually allow prohibiting setting `RUSTC_BOOTSTRAP` in build.rs (https://github.com/rust-lang/cargo/issues/7088).
## User-facing changes
- `RUSTC_BOOTSTRAP=1` still works; there is no current plan to remove this.
- Things like `RUSTC_BOOTSTRAP=0` no longer activate nightly features. In practice this shouldn't be a big deal, since `RUSTC_BOOTSTRAP` is the opposite of stable and everyone uses `RUSTC_BOOTSTRAP=1` anyway.
- `RUSTC_BOOTSTRAP=x` will enable nightly features only for crate `x`.
- `RUSTC_BOOTSTRAP=x,y` will enable nightly features only for crates `x` and `y`.
## Implementation changes
The main change is that `UnstableOptions::from_environment` now requires
an (optional) crate name. If the crate name is unknown (`None`), then the new feature is not available and you still have to use `RUSTC_BOOTSTRAP=1`. In practice this means the feature is only available for `--crate-name`, not for `#![crate_name]`; I'm interested in supporting the second but I'm not sure how.
Other major changes:
- Added `Session::is_nightly_build()`, which uses the `crate_name` of
the session
- Added `nightly_options::match_is_nightly_build`, a convenience method
for looking up `--crate-name` from CLI arguments.
`Session::is_nightly_build()`should be preferred where possible, since
it will take into account `#![crate_name]` (I think).
- Added `unstable_features` to `rustdoc::RenderOptions`
I'm not sure whether this counts as T-compiler or T-lang; _technically_ RUSTC_BOOTSTRAP is an implementation detail, but it's been used so much it seems like this counts as a language change too.
r? `@joshtriplett`
cc `@Mark-Simulacrum` `@hsivonen`
rustc_target: Further cleanup use of target options
Follow up to https://github.com/rust-lang/rust/pull/77729.
Implements items 2 and 4 from the list in https://github.com/rust-lang/rust/pull/77729#issue-500228243.
The first commit collapses uses of `target.options.foo` into `target.foo`.
The second commit renames some target options to avoid tautology:
`target.target_endian` -> `target.endian`
`target.target_c_int_width` -> `target.c_int_width`
`target.target_os` -> `target.os`
`target.target_env` -> `target.env`
`target.target_vendor` -> `target.vendor`
`target.target_family` -> `target.os_family`
`target.target_mcount` -> `target.mcount`
r? `@Mark-Simulacrum`
rustc_ast: Do not panic by default when visiting macro calls
Panicking by default made sense when we didn't have HIR or MIR and everything worked on AST, but now all AST visitors run early and majority of them have to deal with macro calls, often by ignoring them.
The second commit renames `visit_mac` to `visit_mac_call`, the corresponding structures were renamed earlier in https://github.com/rust-lang/rust/pull/69589.
with an eye on merging `TargetOptions` into `Target`.
`TargetOptions` as a separate structure is mostly an implementation detail of `Target` construction, all its fields logically belong to `Target` and available from `Target` through `Deref` impls.
The main change is that `UnstableOptions::from_environment` now requires
an (optional) crate name. If the crate name is unknown (`None`), then the new feature is not available and you still have to use `RUSTC_BOOTSTRAP=1`. In practice this means the feature is only available for `--crate-name`, not for `#![crate_name]`; I'm interested in supporting the second but I'm not sure how.
Other major changes:
- Added `Session::is_nightly_build()`, which uses the `crate_name` of
the session
- Added `nightly_options::match_is_nightly_build`, a convenience method
for looking up `--crate-name` from CLI arguments.
`Session::is_nightly_build()`should be preferred where possible, since
it will take into account `#![crate_name]` (I think).
- Added `unstable_features` to `rustdoc::RenderOptions`
There is a user-facing change here: things like `RUSTC_BOOTSTRAP=0` no
longer active nightly features. In practice this shouldn't be a big
deal, since `RUSTC_BOOTSTRAP` is the opposite of stable and everyone
uses `RUSTC_BOOTSTRAP=1` anyway.
- Add tests
Check against `Cheat`, not whether nightly features are allowed.
Nightly features are always allowed on the nightly channel.
- Only call `is_nightly_build()` once within a function
- Use booleans consistently for rustc_incremental
Sessions can't be passed through threads, so `read_file` couldn't take a
session. To be consistent, also take a boolean in `write_file_header`.
Improve errors about #[deprecated] attribute
This change:
1. Turns `#[deprecated]` on a trait impl block into an error, which fixes#78625;
2. Changes these and other errors about `#[deprecated]` to use the span of the attribute instead of the item; and
3. Turns this error into a lint, to make sure it can be capped with `--cap-lints` and doesn't break any existing dependencies.
Can be reviewed per commit.
---
Example:
```rust
struct X;
#[deprecated = "a"]
impl Default for X {
#[deprecated = "b"]
fn default() -> Self {
X
}
}
```
Before:
```
error: This deprecation annotation is useless
--> src/main.rs:6:5
|
6 | / fn default() -> Self {
7 | | X
8 | | }
| |_____^
```
After:
```
error: this `#[deprecated]' annotation has no effect
--> src/main.rs:3:1
|
3 | #[deprecated = "a"]
| ^^^^^^^^^^^^^^^^^^^ help: try removing the deprecation attribute
|
= note: `#[deny(useless_deprecated)]` on by default
error: this `#[deprecated]' annotation has no effect
--> src/main.rs:5:5
|
5 | #[deprecated = "b"]
| ^^^^^^^^^^^^^^^^^^^ help: try removing the deprecation attribute
```
replace `#[allow_internal_unstable]` with `#[rustc_allow_const_fn_unstable]` for `const fn`s
`#[allow_internal_unstable]` is currently used to side-step feature gate and stability checks.
While it was originally only meant to be used only on macros, its use was expanded to `const fn`s.
This pr adds stricter checks for the usage of `#[allow_internal_unstable]` (only on macros) and introduces the `#[rustc_allow_const_fn_unstable]` attribute for usage on `const fn`s.
This pr does not change any of the functionality associated with the use of `#[allow_internal_unstable]` on macros or the usage of `#[rustc_allow_const_fn_unstable]` (instead of `#[allow_internal_unstable]`) on `const fn`s (see https://github.com/rust-lang/rust/issues/69399#issuecomment-712911540).
Note: The check for `#[rustc_allow_const_fn_unstable]` currently only validates that the attribute is used on a function, because I don't know how I would check if the function is a `const fn` at the place of the check. I therefore openend this as a 'draft pull request'.
Closesrust-lang/rust#69399
r? @oli-obk
fix def collector for impl trait
fixes#77329
We now consistently make `impl Trait` a hir owner, requiring some special casing for synthetic generic params.
r? `@eddyb`
passes: `check_attr` on more targets
This PR modifies `check_attr` so that:
- Enum variants are now checked (some attributes would not have been prohibited on variants previously).
- `check_expr_attributes` and `check_stmt_attributes` are removed as `check_attributes` can perform the same checks. This means that codegen attribute errors aren't shown if there are other errors first (e.g. from other attributes, as shown in `src/test/ui/macros/issue-68060.rs` changes below).
The validation was introduced in 3a63bf0299
without strict validation of functions, e. g. all function types were
allowed.
Now the validation only allows `const fn`s.
Mark inout asm! operands as used in liveness pass
Variables used in `inout` operands in inline assembly (that is, they're used as both input and output to some arbitrary assembly instruction) are being marked as read and written, but are not marked as being used in the RWU table during the liveness pass. This can result in such expressions triggering an unused variable lint warning. This is incorrect behavior- reads without uses are currently only used for compound assignments. We conservatively assume that an `inout` operand is being read and used in the context of the assembly instruction.
Closes#77915
