redundant_locals: fix FPs on mutated shadows
Fixes#11290.
When a mutable binding is shadowed by
a mutable binding of the same name in a different scope, mutations in that scope have different meaning.
This PR fixes spurious `redundant_locals` emissions on such locals.
cc `@Centri3,` `@flip1995`
changelog: [`redundant_locals`]: fix false positives on mutated shadows
make `typeid::typeid_itanium_cxx_abi::transform_ty` evaluate length in array types
the ICE in https://github.com/rust-lang/rust/issues/114275 was caused by `transform_ty`
in compiler/rustc_symbol_mangling/src/typeid/typeid_itanium_cxx_abi.rs encountering an unevaluated const, while expecting it to already be evaluated.
Rustup
r? `@ghost`
cc `@max-niederman` With the latest sync, I'm getting a lot of FP in the `redundant_locals` lint you recently added. Any ideas where this could come from?
changelog: none
Rollup of 7 pull requests
Successful merges:
- #114599 (Add impl trait declarations to SMIR)
- #114622 (rustc: Move `crate_types` and `stable_crate_id` from `Session` to `GlobalCtxt`)
- #114662 (Unlock trailing where-clauses for lazy type aliases)
- #114693 (Remove myself from the review rotation)
- #114694 (make the provisional cache slightly less broken)
- #114705 (Add spastorino to mailmap)
- #114712 (Fix a couple of bad comments)
r? `@ghost`
`@rustbot` modify labels: rollup
Fix documentation of impl From<Vec<T>> for Rc<[T]>
The example in the documentation of `impl From<Vec<T>> for <Rc<[T]>` is irrelevant (likely was copied from `impl From<Box<T>> for <Rc<T>`). I suggest taking corresponding example from the documentation of `Arc` and replacing `Arc` with `Rc`.
[library/std] Replace condv while loop with `cvar.wait_while`.
`wait_while` takes care of spurious wake-ups in centralized place, reducing chances for mistakes and potential future optimizations (who knows, maybe in future there will be no spurious wake-ups? :)
Inline trivial (noop) flush calls
At work I noticed that `writer.flush()?` didn't get optimized away in cases where the flush is obviously a no-op, which I had expected (well, desired).
I went through and added `#[inline]` to a bunch of cases that were obviously noops, or delegated to ones that were obviously noops. I omitted platforms I don't have access to (some tier3). I didn't do this very scientifically, in cases where it was non-obvious I left `#[inline]` off.
Fix a couple of bad comments
A couple of nits I saw. Sorry, this really should be folded into some other PR of mine, but I will literally forget if I don't put these up now.
make the provisional cache slightly less broken
It is still broken for the following cycles:
```mermaid
graph LR
R["R: coinductive"] --> A["A: inductive"]
R --> B["B: coinductive"]
A --> B
B --> R
```
the `R -> A -> B -> R` cycle should be considered to not hold, as it is mixed, but because we first put `B` into the cache from the `R -> B -> R` cycle which is coinductive, it does hold.
This issue will also affect our new coinduction approach. Longterm cycles are coinductive as long as one step goes through an impl where-clause, see f4fc5bae36/crates/formality-prove/src/prove/prove_wc.rs (L51-L62). Here we would first have a fully inductive cycle `R -> B -> R` which is then entered by a cycle with a coinductive step `R -> A -coinductive-> B -> R`.
I don't know how to soundly implement a provisional cache for goals not on the stack without tracking all cycles the goal was involved in and whether they were inductive or not. We could then only use goals from the cache if the *inductivity?* of every cycle remained the same. This is a mess to implement. I therefore want to rip out the provisional cache entirely, but will wait with this until I talked about it with `@nikomatsakis.`
r? `@compiler-errors`
Unlock trailing where-clauses for lazy type aliases
Allows trailing where-clauses on lazy type aliases and forbids[^1] leading ones.
Completes #89122 (see section *Top-level type aliases*).
`@rustbot` label F-lazy_type_alias
r? `@oli-obk`
[^1]: This is absolutely fine since lazy type aliases are only meant to be stabilized as part of a new edition.
When a mutable binding is shadowed by
a mutable binding of the same name in a different scope,
mutations in that scope have different meaning.
This commit fixes spurious `redundant_locals` emissions
on such locals.
[`filter_map_bool_then`]: Don't ICE on late bound regions
Fixes#11309
Also lints `&NonCopy` now, since any `&` is `Copy`. That was accidental, but it seems that this is a consequence (or improvement!) of this fix.
r? `@Jarcho`
changelog: [`filter_map_bool_then`]: Don't ICE on late bound regions
This is inherited from the old PR.
This method returns an iterator over mapped windows of the starting
iterator. Adding the more straight-forward `Iterator::windows` is not
easily possible right now as the items are stored in the iterator type,
meaning the `next` call would return references to `self`. This is not
allowed by the current `Iterator` trait design. This might change once
GATs have landed.
The idea has been brought up by @m-ou-se here:
https://rust-lang.zulipchat.com/#narrow/stream/219381-t-libs/topic/Iterator.3A.3A.7Bpairwise.2C.20windows.7D/near/224587771
Co-authored-by: Lukas Kalbertodt <lukas.kalbertodt@gmail.com>
coverage: Don't convert filename/symbol strings to `CString` for FFI
LLVM APIs are usually perfectly happy to accept pointer/length strings, as long as we supply a suitable length value when creating a `StringRef` or `std::string`.
This lets us avoid quite a few intermediate `CString` copies during coverage codegen. It also lets us use an `IndexSet<Symbol>` (instead of an `IndexSet<CString>`) when building the deduplicated filename table.
Remove redundant calls to `resolve_vars_with_obligations`
I've been auditing the calls to `resolve_vars_with_obligations` for the new solver, and have found a few that have no effect on diagnostics. Let's just remove 'em.
Also remove a redundant `resolve_vars_with_obligations_and_mutate_fulfillment` call.
r? ``@lcnr``
`Expr::can_have_side_effects()` is incorrect for struct/enum/array/tuple literals
It would return 'false' unless *all* sub-expressions had side effects. This would easily allow side effects to slip through, and also wrongly label empty literals as having side effects. Add some tests for the last point
The function is only used for simple lints and error messages, so not a serious bug.
