Make `PointerLike` opt-in instead of built-in
The `PointerLike` trait currently is a built-in trait that computes the layout of the type. This is a bit problematic, because types implement this trait automatically. Since this can be broken due to semver-compatible changes to a type's layout, this is undesirable. Also, calling `layout_of` in the trait system also causes cycles.
This PR makes the trait implemented via regular impls, and adds additional validation on top to make sure that those impls are valid. This could eventually be `derive()`d for custom smart pointers, and we can trust *that* as a semver promise rather than risking library authors accidentally breaking it.
On the other hand, we may never expose `PointerLike`, but at least now the implementation doesn't invoke `layout_of` which could cause ICEs or cause cycles.
Right now for a `PointerLike` impl to be valid, it must be an ADT that is `repr(transparent)` and the non-1zst field needs to implement `PointerLike`. There are also some primitive impls for `&T`/ `&mut T`/`*const T`/`*mut T`/`Box<T>`.
Point at `const` definition when used instead of a binding in a `let` statement
Modify `PatKind::InlineConstant` to be `ExpandedConstant` standing in not only for inline `const` blocks but also for `const` items. This allows us to track named `const`s used in patterns when the pattern is a single binding. When we detect that there is a refutable pattern involving a `const` that could have been a binding instead, we point at the `const` item, and suggest renaming. We do this for both `let` bindings and `match` expressions missing a catch-all arm if there's at least one single binding pattern referenced.
After:
```
error[E0005]: refutable pattern in local binding
--> $DIR/bad-pattern.rs:19:13
|
LL | const PAT: u32 = 0;
| -------------- missing patterns are not covered because `PAT` is interpreted as a constant pattern, not a new variable
...
LL | let PAT = v1;
| ^^^ pattern `1_u32..=u32::MAX` not covered
|
= note: `let` bindings require an "irrefutable pattern", like a `struct` or an `enum` with only one variant
= note: for more information, visit https://doc.rust-lang.org/book/ch18-02-refutability.html
= note: the matched value is of type `u32`
help: introduce a variable instead
|
LL | let PAT_var = v1;
| ~~~~~~~
```
Before:
```
error[E0005]: refutable pattern in local binding
--> $DIR/bad-pattern.rs:19:13
|
LL | let PAT = v1;
| ^^^
| |
| pattern `1_u32..=u32::MAX` not covered
| missing patterns are not covered because `PAT` is interpreted as a constant pattern, not a new variable
| help: introduce a variable instead: `PAT_var`
|
= note: `let` bindings require an "irrefutable pattern", like a `struct` or an `enum` with only one variant
= note: for more information, visit https://doc.rust-lang.org/book/ch18-02-refutability.html
= note: the matched value is of type `u32`
```
CC #132582.
Mark `get_mut` and `set_position` in `std::io::Cursor` as const.
Relevant tracking issue: #130801
The methods `get_mut` and `set_position` can trivially be marked as const due to #57349 being stabilised.
interpret: make typing_env field private
This was made public in https://github.com/rust-lang/rust/pull/133212 but IMO it should remain private. (Specifically, this prevents it from being mutated.)
r? `@lcnr`
Update cargo
5 commits in 69e595908e2c420e7f0d1be34e6c5b984c8cfb84..66221abdeca2002d318fde6efff516aab091df0e
2024-11-16 01:26:11 +0000 to 2024-11-19 21:30:02 +0000
- Docs for optional registry JSON fields (rust-lang/cargo#14839)
- Allow registries to omit empty/default fields in JSON (rust-lang/cargo#14838)
- docs(unstable): Link to -Zwarnings issue, tracking issue (rust-lang/cargo#14836)
- fix(): error context for git_fetch refspec not found (rust-lang/cargo#14806)
- you we distinction (rust-lang/cargo#14829)
lints_that_dont_need_to_run: never skip future-compat-reported lints
Follow-up to https://github.com/rust-lang/rust/pull/125116: future-compat lints show up with `--json=future-incompat` even if they are otherwise allowed in the crate. So let's ensure we do not skip those as part of the `lints_that_dont_need_to_run` logic.
I could not find a current future compat lint that is emitted by a lint pass, so there's no clear way to add a test for this.
Cc `@blyxyas` `@cjgillot`
Use attributes for `dangling_pointers_from_temporaries` lint
Checking for dangling pointers by function name isn't ideal, and leaves out certain pointer-returning methods that don't follow the `as_ptr` naming convention. Using an attribute for this lint cleans things up and allows more thorough coverage of other methods, such as `UnsafeCell::get()`.
Drop debug info instead of panicking if we exceed LLVM's capability to represent it
Recapping a bit of history here:
In #128861 I made debug info correctly represent parameters to inline functions by removing a fake lexical block that had been inserted to suppress LLVM assertions and by deduplicating those parameters.
LLVM, however, expects to see a single parameter _with distinct locations_, particularly distinct inlinedAt values on the DILocations. This generally worked because no matter how deep the chain of inlines it takes two different call sites in the original function to result in the same function being present multiple times, and a function call requires a non-zero number of characters, but macros threw a wrench in that in #131944. At the time I thought the issue there was limited to proc-macros, where an arbitrary amount of code can be generated at a single point in the source text.
In #132613 I added discriminators to DILocations that would otherwise be the same to repair #131944[^1]. This works, but LLVM's capacity for discriminators is not infinite (LLVM actually only allocates 12 bits for this internally). At the time I thought it would be very rare for anyone to hit the limit, but #132900 proved me wrong. In the relatively-minimized test case it also became clear to me that the issue affects regular macros too, because the call to the inlined function will (without collapse_debuginfo on the macro) be attributed to the (repeated, if the macro is used more than once) textual callsite in the macro definition.
This PR fixes the panic by dropping debug info when we exceed LLVM's maximum discriminator value. There's also a preceding commit for a related but distinct issue: macros that use collapse_debuginfo should in fact have their inlinedAts collapsed to the macro callsite and thus not need discriminators at all (and not panic/warn accordingly when the discriminator limit is exhausted).
Fixes#132900
r? `@jieyouxu`
[^1]: Editor's note: `fix` is a magic keyword in PR description that apparently will close the linked issue (it's closed already in this case, but still).
Default-enable `llvm_tools_enabled` when no `config.toml` is present
Fixes#133195. cc `@wesleywiser` could you double check if with this patch and no `config.toml` that you can run `./x test tests/ui --stage 1`?
`llvm-objcopy` is usually required by cg_ssa on macOS to workaround bad `strip`s.
cc `@bjorn3` I hope this doesn't break cg_clif...
r? bootstrap
Add `visit` methods to ast nodes that already have `walk`s on ast visitors
Some `walk` functions are called directly, because there were no correspondent visit functions.
related to #128974 & #127615
r? `@petrochenkov`
Add vec_deque::Iter::as_slices and friends
Add the following methods, that work similarly to VecDeque::as_slices:
- alloc::collections::vec_deque::Iter::as_slices
- alloc::collections::vec_deque::IterMut::into_slices
- alloc::collections::vec_deque::IterMut::as_slices
- alloc::collections::vec_deque::IterMut::as_mut_slices
Obtaining slices from a VecDeque iterator was not previously possible.
