rustc_expand: remember module `#[path]`s during expansion
During invocation collection, if a module item parsed from a `#[path]` attribute needed a second pass after parsing, its path wouldn't get added to the file path stack, so cycle detection broke. This checks the `#[path]` in such cases, so that it gets added appropriately. I think it should work identically to the case for external modules that don't need a second pass, but I'm not 100% sure.
Fixes#97589
Fix anon const def-creation when macros are involved take 2
Fixes#130321
There were two cases that #129137 did not handle correctly:
- Given a const argument `Foo<{ bar!() }>` in which `bar!()` expands to `N`, we would visit the anon const and then visit the `{ bar() }` expression instead of visiting the macro call. This meant that we would build a def for the anon const as `{ bar!() }` is not a trivial const argument as `bar!()` is not a path.
- Given a const argument `Foo<{ bar!() }>` is which `bar!()` expands to `{ qux!() }` in which `qux!()` expands to `N`, it should not be considered a trivial const argument as `{{ N }}` has two pairs of braces. If we only looked at `qux`'s expansion it would *look* like a trivial const argument even though it is not. We have to track whether we have "unwrapped" a brace already when recursing into the expansions of `bar`/`qux`/any macro
r? `@camelid`
Assert that `explicit_super_predicates_of` and `explicit_item_super_predicates` truly only contains bounds for the type itself
We distinguish _implied_ predicates (anything that is implied from elaborating a trait bound) from _super_ predicates, which are are the subset of implied predicates that share the same self type as the trait predicate we're elaborating. This was originally done in #107614, which fixed a large class of ICEs and strange errors where the compiler expected the self type of a trait predicate not to change when elaborating super predicates.
Specifically, super predicates are special for various reasons: they're the valid candidates for trait upcasting, are the only predicates we elaborate when doing closure signature inference, etc. So making sure that we get this list correct and don't accidentally "leak" any other predicates into this list is quite important.
This PR adds some debug assertions that we're in fact not doing so, and it fixes an oversight in the effect desugaring rework.
Implement Return Type Notation (RTN)'s path form in where clauses
Implement return type notation (RTN) in path position for where clauses. We already had RTN in associated type position ([e.g.](https://play.rust-lang.org/?version=nightly&mode=debug&edition=2021&gist=627a4fb8e2cb334863fbd08ed3722c09)), but per [the RFC](https://rust-lang.github.io/rfcs/3654-return-type-notation.html#where-rtn-can-be-used-for-now):
> As a standalone type, RTN can only be used as the Self type of a where-clause [...]
Specifically, in order to enable code like:
```rust
trait Foo {
fn bar() -> impl Sized;
}
fn is_send(_: impl Send) {}
fn test<T>()
where
T: Foo,
T::bar(..): Send,
{
is_send(T::bar());
}
```
* In the resolver, when we see a `TyKind::Path` whose final segment is `GenericArgs::ParenthesizedElided` (i.e. `(..)`), resolve that path in the *value* namespace, since we're looking for a method.
* When lowering where clauses in HIR lowering, we first try to intercept an RTN self type via `lower_ty_maybe_return_type_notation`. If we find an RTN type, we lower it manually in a way that respects its higher-ranked-ness (see below) and resolves to the corresponding RPITIT. Anywhere else, we'll emit the same "return type notation not allowed in this position yet" error we do when writing RTN in every other position.
* In `resolve_bound_vars`, we add some special treatment for RTN types in where clauses. Specifically, we need to add new lifetime variables to our binders for the early- and late-bound vars we encounter on the method. This implements the higher-ranked desugaring [laid out in the RFC](https://rust-lang.github.io/rfcs/3654-return-type-notation.html#converting-to-higher-ranked-trait-bounds).
This PR also adds a bunch of tests, mostly negative ones (testing error messages).
In a follow-up PR, I'm going to mark RTN as no longer incomplete, since this PR basically finishes the impl surface that we should initially stabilize, and the RFC was accepted.
cc [RFC 3654](https://github.com/rust-lang/rfcs/pull/3654) and https://github.com/rust-lang/rust/issues/109417
add `extern "C-cmse-nonsecure-entry" fn`
tracking issue #75835
in https://github.com/rust-lang/rust/issues/75835#issuecomment-1183517255 it was decided that using an abi, rather than an attribute, was the right way to go for this feature.
This PR adds that ABI and removes the `#[cmse_nonsecure_entry]` attribute. All relevant tests have been updated, some are now obsolete and have been removed.
Error 0775 is no longer generated. It contains the list of targets that support the CMSE feature, and maybe we want to still use this? right now a generic "this abi is not supported on this platform" error is returned when this abi is used on an unsupported platform. On the other hand, users of this abi are likely to be experienced rust users, so maybe the generic error is good enough.
Correct outdated object size limit
The comment here about 48 bit addresses being enough was written in 2016 but was made incorrect in 2019 by 5-level paging, and then persisted for another 5 years before being noticed and corrected.
The bolding of the "exclusive" part is merely to call attention to something I missed when reading it and doublechecking the math.
try-job: i686-msvc
try-job: test-various
Don't alloca for unused locals
We already have a concept of mono-unreachable basic blocks; this is primarily useful for ensuring that we do not compile code under an `if false`. But since we never gave locals the same analysis, a large local only used under an `if false` will still have stack space allocated for it.
There are 3 places we traverse MIR during monomorphization: Inside the collector, `non_ssa_locals`, and the walk to generate code. Unfortunately, https://github.com/rust-lang/rust/pull/129283#issuecomment-2297925578 indicates that we cannot afford the expense of tracking reachable locals during the collector's traversal, so we do need at least two mono-reachable traversals. And of course caching is of no help here because the benchmarks that regress are incr-unchanged; they don't do any codegen.
This fixes the second problem in https://github.com/rust-lang/rust/issues/129282, and brings us anther step toward `const if` at home.
Explain why `non_snake_case` is skipped for binary crates and cleanup tests
- Explain `non_snake_case` lint is skipped for bin crate names because binaries are not intended to be distributed or consumed like library crates (#45127).
- Coalesce the bunch of tests into a single one but with revisions, which is easier to compare the differences for `non_snake_case` behavior with respect to crate types.
Follow-up to #121749 with some more comments and test cleanup.
cc `@saethlin` who bumped into one of the tests and was confused why it was `only-x86_64-unknown-linux-gnu`.
try-job: dist-i586-gnu-i586-i686-musl
Normalize consts in writeback when GCE is enabled
GCE lazily normalizes its unevaluated consts. This PR ensures that, like the new solver with its lazy norm types, we can assume that the writeback results are fully normalized.
This is important since we're trying to eliminate unnecessary calls to `ty::Const::{eval,normalize}` since they won't work with mGCE. Previously, we'd keep those consts unnormalized in writeback all the way through MIR build, and they'd only get normalized if we explicitly called `ty::Const::{eval,normalize}`, or during codegen since that calls `normalize_erasing_regions` (which invokes the `QueryNormalizer`, which evaluates the const accordingly).
This hack can (hopefully obviously) be removed when mGCE is implemented and we yeet the old GCE; it's only reachable with the GCE flag anyways, so I'm not worried about the implications here.
r? `@BoxyUwU`
Pass the current cargo to `run-make` tests
A couple tests were using `BOOTSTRAP_CARGO` with `-Zbuild-std`, but that
stage0 cargo might not always be in sync with in-tree changes. In
particular, those tests started failing on the beta branch because the
older cargo couldn't find the library `Cargo.lock`, and then couldn't
build the latest version of `compiler_builtins` that had nightly changes.
Fixes#130634
r? `@saethlin`
Add recursion limit to FFI safety lint
Fixes#130310
Now we check against `tcx.recursion_limit()` and raise an error if it the limit is reached instead of overflowing the stack.
A couple tests were using `BOOTSTRAP_CARGO` with `-Zbuild-std`, but that
stage0 cargo might not always be in sync with in-tree changes. In
particular, those tests started failing on the beta branch because the
older cargo couldn't find the library `Cargo.lock`, and then couldn't
build the latest version of `compiler_builtins` that had nightly changes.
bail if there are too many non-region infer vars in the query response
A minimal fix for the hang in nalgebra. If the query response would result in too many distinct non-region inference variables, simply overwrite the result with overflow. This should either happen if the result already has too many distinct type inference variables, or if evaluating the query encountered a lot of ambiguous associated types. In both cases it's straightforward to wait until the aliases are no longer ambiguous and then try again.
r? `@compiler-errors`
Add arm64e-apple-tvos target
This introduces
* `arm64e-apple-tvos`
## Tier 3 Target Policy
> * A tier 3 target must have a designated developer or developers (the "target
maintainers") on record to be CCed when issues arise regarding the target.
(The mechanism to track and CC such developers may evolve over time.)
I will be a target maintainer.
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target for the same CPU or OS as an existing Rust target should use the same
name for that CPU or OS. Targets should normally use the same names and
naming conventions as used elsewhere in the broader ecosystem beyond Rust
(such as in other toolchains), unless they have a very good reason to
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once the target reaches a higher tier, so getting the name right is important
even for a tier 3 target.
Target names should not introduce undue confusion or ambiguity unless
absolutely necessary to maintain ecosystem compatibility. For example, if
the name of the target makes people extremely likely to form incorrect
beliefs about what it targets, the name should be changed or augmented to
disambiguate it.
If possible, use only letters, numbers, dashes and underscores for the name.
Periods (.) are known to cause issues in Cargo.
The `arm64e-apple-tvos` target names like `arm64e-apple-ios`, `arm64e-apple-darwin`.
So, **I have chosen this name because there are similar triplets in LLVM**. I think there are no more suitable names for these targets.
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No dependencies were added to Rust.
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subjective matters or goes beyond the letter of these requirements.
Understood.
I am not a member of a Rust team.
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as possible and appropriate (core for most targets, alloc for targets
that can support dynamic memory allocation, std for targets with an
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Understood.
`std` is supported.
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to build for the target, using cross-compilation if possible. If the target
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Understood.
https://github.com/rust-lang/rust/issues/121663https://github.com/rust-lang/rust/issues/73628
Begin experimental support for pin reborrowing
This commit adds basic support for reborrowing `Pin` types in argument position. At the moment it only supports reborrowing `Pin<&mut T>` as `Pin<&mut T>` by inserting a call to `Pin::as_mut()`, and only in argument position (not as the receiver in a method call).
This PR makes the following example compile:
```rust
#![feature(pin_ergonomics)]
fn foo(_: Pin<&mut Foo>) {
}
fn bar(mut x: Pin<&mut Foo>) {
foo(x);
foo(x);
}
```
Previously, you would have had to write `bar` as:
```rust
fn bar(mut x: Pin<&mut Foo>) {
foo(x.as_mut());
foo(x);
}
```
Tracking:
- #130494
r? `@compiler-errors`
Remove macOS 10.10 dynamic linker bug workaround
Rust's current minimum macOS version is 10.12, so the hack can be removed. This PR also updates the `remove_dir_all` docs to reflect that all supported macOS versions are protected against TOCTOU race conditions (the fallback implementation was already removed in #127683).
try-job: dist-x86_64-apple
try-job: dist-aarch64-apple
try-job: dist-apple-various
try-job: aarch64-apple
try-job: x86_64-apple-1
The issue-112505-overflow test just extended a case of transmute-fail.rs
so simply put them in the same file.
Then we normalize away other cases of this.
Fix feature name in test
This is meant to test that the `box_patterns` feature isn't active due to the `cfg(FALSE)`, but uses the removed `box_syntax` feature. Fix this so it's testing what it should be.
