Suggest `i += 1` when we see `i++` or `++i`
Closes#83502 (for `i++` and `++i`; `--i` should be covered by #82987, and `i--`
is tricky to handle).
This is a continuation of #83536.
r? `@estebank`
Fix multiline attributes handling in doctests
Fixes#55713.
I needed to have access to the `unclosed_delims` field in order to check that the attribute was completely parsed and didn't have missing parts, so I created a getter for it.
r? `@notriddle`
Rollup of 4 pull requests
Successful merges:
- #95587 (Remove need for associated_type_bounds in std.)
- #95589 (Include a header in .rlink files)
- #95593 (diagnostics: add test case for bogus T:Sized suggestion)
- #95597 (Refer to u8 by absolute path in expansion of thread_local)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Include a header in .rlink files
I couldn't find the right place where to put tests. Is there some location that tests `.rlink` creation and loading?
I only found `src/test/run-make-fulldeps/separate-link/Makefile`, but I'm not sure how to check the error message in the Makefile.
Fixes: https://github.com/rust-lang/rust/issues/95297
r? `@bjorn3`
Make GATs object safe under generic_associated_types_extended feature
Based on #94869
Let's say we have
```rust
trait StreamingIterator {
type Item<'a> where Self: 'a;
}
```
And `dyn for<'a> StreamingIterator<Item<'a> = &'a i32>`.
If we ask `(dyn for<'a> StreamingIterator<Item<'a> = &'a i32>): StreamingIterator`, then we have to prove that `for<'x> (&'x i32): Sized`. So, we generate *new* bound vars to subst for the GAT generics.
Importantly, this doesn't fully verify that these are usable and sound.
r? `@nikomatsakis`
Add error message suggestion for missing noreturn in naked function
I had to google the syntax for inline asm's `noreturn` option when I got this error earlier today, so I figured I'd save others the trouble and add the syntax/fix as a suggestion in the error.
Handle rustc_const_stable attribute in library feature collector
The library feature collector in [compiler/rustc_passes/src/lib_features.rs](551b4fa395/compiler/rustc_passes/src/lib_features.rs) has only been looking at `#[stable(…)]`, `#[unstable(…)]`, and `#[rustc_const_unstable(…)]` attributes, while ignoring `#[rustc_const_stable(…)]`. The consequences of this were:
- When any const feature got stabilized (changing one or more `rustc_const_unstable` to `rustc_const_stable`), users who had previously enabled that unstable feature using `#![feature(…)]` would get told "unknown feature", rather than rustc's nicer "the feature … has been stable since … and no longer requires an attribute to enable".
This can be seen in the way that https://github.com/rust-lang/rust/pull/93957#issuecomment-1079794660 failed after rebase:
```console
error[E0635]: unknown feature `const_ptr_offset`
--> $DIR/offset_from_ub.rs:1:35
|
LL | #![feature(const_ptr_offset_from, const_ptr_offset)]
| ^^^^^^^^^^^^^^^^
```
- We weren't enforcing that a particular feature is either stable everywhere or unstable everywhere, and that a feature that has been stabilized has the same stabilization version everywhere, both of which we enforce for the other stability attributes.
This PR updates the library feature collector to handle `rustc_const_stable`, and fixes places in the standard library and test suite where `rustc_const_stable` was being used in a way that does not meet the rules for a stability attribute.
Rollup of 6 pull requests
Successful merges:
- #95032 (Clean up, categorize and sort unstable features in std.)
- #95260 (Better suggestions for `Fn`-family trait selection errors)
- #95293 (suggest wrapping single-expr blocks in square brackets)
- #95344 (Make `impl Debug for rustdoc::clean::Item` easier to read)
- #95388 (interpret: make isize::MAX the limit for dynamic value sizes)
- #95530 (rustdoc: do not show primitives and keywords as private)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
interpret: make isize::MAX the limit for dynamic value sizes
We are currently enforcing `data_layout.obj_size_bound()` as the maximal dynamic size of a Rust value (including for `size_of_val_raw`), but that does not match the docs.
In particular, Miri currently falsely says that this code has UB:
```rust
#![feature(layout_for_ptr)]
fn main() {
let size = isize::MAX as usize;
// Creating a raw slice of size isize::MAX and asking for its size is okay.
let s = std::ptr::slice_from_raw_parts(1usize as *const u8, size);
assert_eq!(size, unsafe { std::mem::size_of_val_raw(s) });
}
```
Better suggestions for `Fn`-family trait selection errors
1. Suppress suggestions to add `std::ops::Fn{,Mut,Once}` bounds when a type already implements `Fn{,Mut,Once}`
2. Add a note that points out that a type does in fact implement `Fn{,Mut,Once}`, but the arguments vary (either by number or by actual arguments)
3. Add a note that points out that a type does in fact implement `Fn{,Mut,Once}`, but not the right one (e.g. implements `FnMut`, but `Fn` is required).
Fixes#95147
Specialize infinite-type "insert some indirection" suggestion for Option
Suggest `Option<Box<_>>` instead of `Box<Option<_>>` for infinitely-recursive members of a struct.
Not sure if I can get the span of the generic subty of the Option so I can make this a `+++`-style suggestion. The current output is a tiny bit less fancy looking than the original suggestion.
Should I limit the specialization to just `Option<Box<TheOuterStruct>>`? Because right now it applies to all `Option` members in the struct that are returned by `Representability::SelfRecursive`.
Fixes#91402
r? `@estebank`
(since you wrote the original suggestion and are definitely most familiar with it!)
Make lowering pull-based
~Based on https://github.com/rust-lang/rust/pull/90451~
Part of https://github.com/rust-lang/rust/pull/88186
The current lowering code visits all the item-likes in the AST in order, and lowers them one by one.
This PR changes it to index the AST and then proceed to lowering on-demand. This is closer to the logic of query-based lowering.
allow large Size again
This basically reverts most of https://github.com/rust-lang/rust/pull/80042, and instead does the panic in `bits()` with a `#[cold]` function to make sure it does not get inlined.
https://github.com/rust-lang/rust/pull/80042 added a comment about an invariant ("The top 3 bits are ALWAYS zero") that is not actually enforced, and if it were enforced that would be a problem for https://github.com/rust-lang/rust/pull/95388. So I think we should not have that invariant, and I adjusted the code accordingly.
r? `@oli-obk` Cc `@sivadeilra`
It's only used in one place, and there we clone and then make a bunch of
modifications. It's clearer if we duplicate more explicitly, and there's
a symmetry now between `sequence()` and `empty_sequence()`.
`parse_tt` needs a way to get from within submatchers make to the
enclosing submatchers. Currently it has two distinct mechanisms for
this:
- `Delimited` submatchers use `MatcherPos::stack` to record stuff about
the parent (and further back ancestors).
- `Sequence` submatchers use `MatcherPosSequence::parent` to point to
the parent matcher position.
Having two mechanisms is really confusing, and it took me a long time to
understand all this.
This commit eliminates `MatcherPos::stack`, and changes `Delimited`
submatchers to use the same mechanism as sequence submatchers. That
mechanism is also changed a bit: instead of storing the entire parent
`MatcherPos`, we now only store the necessary parts from the parent
`MatcherPos`.
Overall this is a small performance win, with the positives outweighing
the negatives, but it's mostly for clarity.
Spellchecking compiler comments
This PR cleans up the rest of the spelling mistakes in the compiler comments. This PR does not change any literal or code spelling issues.
Don't ICE when opaque types get their hidden type constrained again.
Contrary to popular belief, `codegen_fulfill_obligation` does not get used solely in codegen, so we cannot rely on `param_env` being set to RevealAll and thus revealing the hidden types instead of constraining them.
Fixes#89312 (for real this time)
Restore `impl Future<Output = Type>` to async blocks
I was sad when I undid some of the code I wrote in #91096 in the PR #95225, so I fixed it here to not print `[async output]`.
This PR "manually" normalizes the associated type `<[generator] as Generator>::Return` type which appears very frequently in `impl Future` types that result from async block desugaring.
Currently, we detect an exit from a `Delimited` submatcher when `idx`
exceeds the bounds of the current submatcher *and* there is a `stack`
entry.
This commit changes it to something simpler: just look for a
`CloseDelim` token.
Rollup of 6 pull requests
Successful merges:
- #93901 (Stabilize native library modifier syntax and the `whole-archive` modifier specifically)
- #94806 (Fix `cargo run tidy`)
- #94869 (Add the generic_associated_types_extended feature)
- #95011 (async: Give predictable name to binding generated from .await expressions.)
- #95251 (Reduce max hash in raw strings from u16 to u8)
- #95298 (Fix double drop of allocator in IntoIter impl of Vec)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
async: Give predictable name to binding generated from .await expressions.
This name makes it to debuginfo and allows debuggers to identify such bindings and their captured versions in suspended async fns.
This will be useful for async stack traces, as discussed in https://internals.rust-lang.org/t/async-debugging-logical-stack-traces-setting-goals-collecting-examples/15547.
I don't know if this needs some discussion by ````@rust-lang/compiler,```` e.g. about the name of the binding (`__awaitee`) or about the fact that this PR introduces a (soft) guarantee about a compiler generated name. Although, regarding the later, I think the same reasoning applies here as it does for debuginfo in general.
r? ````@tmandry````
Add the generic_associated_types_extended feature
Right now, this only ignore obligations that reference new placeholders in `poly_project_and_unify_type`. In the future, this might do other things, like allowing object-safe GATs.
**This feature is *incomplete* and quite likely unsound. This is mostly just for testing out potential future APIs using a "relaxed" set of rules until we figure out *proper* rules.**
Also drive by cleanup of adding a `ProjectAndUnifyResult` enum instead of using a `Result<Result<Option>>`.
r? `@nikomatsakis`
Remember mutability in `DefKind::Static`.
This allows to compute the `BodyOwnerKind` from `DefKind` only, and
removes a direct dependency of some MIR queries onto HIR.
As a side effect, it also simplifies metadata, since we don't need 4
flavours of `EntryKind::*Static` any more.
Yet more `parse_tt` improvements
Including lots of comment improvements, and an overhaul of how `matches` work that gives big speedups.
r? `@petrochenkov`
Contrary to popular belief, `codegen_fulfill_obligation` does not get used solely in codegen, so we cannot rely on `param_env` being set to RevealAll and thus revealing the hidden types instead of constraining them.
allow arbitrary inherent impls for builtin types in core
Part of https://github.com/rust-lang/compiler-team/issues/487. Slightly adjusted after some talks with `@m-ou-se` about the requirements of `t-libs-api`.
This adds a crate attribute `#![rustc_coherence_is_core]` which allows arbitrary impls for builtin types in core.
For other library crates impls for builtin types should be avoided if possible. We do have to allow the existing stable impls however. To prevent us from accidentally adding more of these in the future, there is a second attribute `#[rustc_allow_incoherent_impl]` which has to be added to **all impl items**. This only supports impls for builtin types but can easily be extended to additional types in a future PR.
This implementation does not check for overlaps in these impls. Perfectly checking that requires us to check the coherence of these incoherent impls in every crate, as two distinct dependencies may add overlapping methods. It should be easy enough to detect if it goes wrong and the attribute is only intended for use inside of std.
The first two commits are mostly unrelated cleanups.
Strict Provenance MVP
This patch series examines the question: how bad would it be if we adopted
an extremely strict pointer provenance model that completely banished all
int<->ptr casts.
The key insight to making this approach even *vaguely* pallatable is the
ptr.with_addr(addr) -> ptr
function, which takes a pointer and an address and creates a new pointer
with that address and the provenance of the input pointer. In this way
the "chain of custody" is completely and dynamically restored, making the
model suitable even for dynamic checkers like CHERI and Miri.
This is not a formal model, but lots of the docs discussing the model
have been updated to try to the *concept* of this design in the hopes
that it can be iterated on.
See #95228
