Fix the conflict problem between the diagnostics fixes of lint `unnecessary_qualification` and `unused_imports`
fixes#121331
For an `item` that triggers lint unnecessary_qualification, if the `use item` which imports this item is also trigger unused import, fixing the two lints at the same time may lead to the problem that the `item` cannot be found.
This PR will avoid reporting lint unnecessary_qualification when conflict occurs.
r? ``@petrochenkov``
coverage: Initial support for branch coverage instrumentation
(This is a review-ready version of the changes that were drafted in #118305.)
This PR adds support for branch coverage instrumentation, gated behind the unstable flag value `-Zcoverage-options=branch`. (Coverage instrumentation must also be enabled with `-Cinstrument-coverage`.)
During THIR-to-MIR lowering (MIR building), if branch coverage is enabled, we collect additional information about branch conditions and their corresponding then/else blocks. We inject special marker statements into those blocks, so that the `InstrumentCoverage` MIR pass can reliably identify them even after the initially-built MIR has been simplified and renumbered.
The rest of the changes are mostly just plumbing needed to gather up the information that was collected during MIR building, and include it in the coverage metadata that we embed in the final binary.
Note that `llvm-cov show` doesn't print branch coverage information in its source views by default; that needs to be explicitly enabled with `--show-branches=count` or similar.
---
The current implementation doesn't have any support for instrumenting `if let` or let-chains. I think it's still useful without that, and adding it would be non-trivial, so I'm happy to leave that for future work.
Make incremental sessions identity no longer depend on the crate names provided by source code
This makes incremental sessions identity no longer depend on the crate names provided by source code, implementing
https://github.com/rust-lang/compiler-team/issues/726.
r? ````@oli-obk````
[AIX] Remove AixLinker's debuginfo() implementation
AIX ld's `-s` option doesn't perfectly fit` debuginfo()`'s semantics and may unexpectedly remove metadata in shared libraries. Remove the implementation of `AixLinker` and suggest user to use `strip` utility instead.
Ungate the `UNKNOWN_OR_MALFORMED_DIAGNOSTIC_ATTRIBUTES` lint
This was missed during stablisation of the `#[diagnostic]` attribute namespace.
Fixes#122446
Fix WF for `AsyncFnKindHelper` in new trait solver
`to_opt_closure_kind` ICEs when it sees placeholders... so don't do that
no test b/c I'm too lazy to write a no-core test for this, but I could be convinced otherwise
r? lcnr
Various cleanups around the const eval query providers
r? `@RalfJung`
after this, working on running validation before interning starts with swapping the order of two lines of code
add test ensuring simd codegen checks don't run when a static assertion failed
stdarch relies on this to ensure that SIMD indices are in bounds.
I would love to know why this works, but I can't figure out where codegen decides to not codegen a function if a required-const does not evaluate. `@oli-obk` `@bjorn3` do you have any idea?
Document some builtin impls in the next solver
This does not cover all builtin impls, but ones that I were able to go over within a cycle.
r? `@lcnr`
Let me know if the place isn't correct for these, or if you'd like me to change how the impls are presented ^^
Create some minimal HIR for associated opaque types
`LocalDefId`s for opaque types in traits and impls are created after AST -> HIR lowering, so they don't have corresponding HIR and return their various properties through fed queries.
In this PR I also feed some core HIR-related queries for these `LocalDefId`s (which happen to be HIR owners).
As a result all `LocalDefId`s now have corresponding `HirId`s and HIR nodes, and "optional" methods like `opt_local_def_id_to_hir_id` and `opt_hir_node_by_def_id` can be removed.
Follow up to https://github.com/rust-lang/rust/pull/120206.
Various style improvements to `rustc_lint::levels`
While reading this file, I noticed a few opportunities to make things a little nicer:
- Replace some nested if-let with let-chains
- Tweak a match pattern to allow shorthand struct syntax
- Fuse an `is_empty` check with getting the last element
- Merge some common code that emits `MalformedAttribute` and continues
- Format `"{tool}::{name}"` in a way that's consistent with other match arms
- Replace if-let-else-panic with let-else
- Use early-exit to flatten a method body
Some of these changes cause indentation churn, so ignoring whitespace is recommended.
Add methods to create StableMIR constant
I've been experimenting with transforming the StableMIR to instrument the code with potential UB checks.
The modified body will only be used by our analysis tool, however, constants in StableMIR must be backed by rustc constants. Thus, I'm adding a few functions to build constants, such as building string and other primitives.
One question I have is whether we should create a global allocation instead for strings.
r? ``````@oli-obk``````
interpret: ensure that Place is never used for a different frame
We store the address where the stack frame stores its `locals`. The idea is that even if we pop and push, or switch to a different thread with a larger number of frames, then the `locals` address will most likely change so we'll notice that problem. This is made possible by some recent changes by `@WaffleLapkin,` where we no longer use `Place` across things that change the number of stack frames.
I made these debug assertions for now, just to make sure this can't cost us any perf.
The first commit is unrelated but it's a one-line comment change so it didn't warrant a separate PR...
r? `@oli-obk`
Downgrade const eval dangling ptr in final to future incompat lint
Short term band-aid for issue #121610, downgrading the prior hard error to a future-incompat lint (tracked in issue #122153).
Note we should not mark #121610 as resolved until after this (or something analogous) is beta backported.
extend docs of -Zprint-mono-items
Currently the values one can set this to are not documented anywhere.
I think ideally this flag wouldn't overwrite the collector's behavior, a "print" flag should just print what happens but not change what happens. But our codegen-units tests rely on being able to collect all items without the other side-effects of `-C link-dead-code` and I can't tell whether that reliance is incidental or crucial, so I'm not touching this and just documenting the (messy) status quo.
Safe Transmute: Require that source referent is smaller than destination
`BikeshedIntrinsicFrom` currently models transmute-via-union; i.e., it attempts to provide a `where` bound for this function:
```rust
pub unsafe fn transmute_via_union<Src, Dst>(src: Src) -> Dst {
use core::mem::*;
#[repr(C)]
union Transmute<T, U> {
src: ManuallyDrop<T>,
dst: ManuallyDrop<U>,
}
let transmute = Transmute { src: ManuallyDrop::new(src) };
// SAFETY: The caller must guarantee that the transmutation is safe.
let dst = transmute.dst;
ManuallyDrop::into_inner(dst)
}
```
A quirk of this model is that it admits padding extensions in value-to-value transmutation: The destination type can be bigger than the source type, so long as the excess consists of uninitialized bytes. However, this isn't permissible for reference-to-reference transmutations (introduced in #110662) — extra referent bytes cannot come from thin air.
This PR patches our analysis for reference-to-reference transmutations to require that the destination referent is no larger than the source referent.
r? `@compiler-errors`
pattern analysis: remove `MaybeInfiniteInt::JustAfterMax`
It was inherited from before half-open ranges, but it doesn't pull its weight anymore. We lose a tiny bit of diagnostic precision as can be seen in the test. I'm generally in favor of half-open ranges over explicit `x..=MAX` ranges anyway.
pattern analysis: rename a few types
A few long overdue renames. `ValidityConstraint` was supposed to serve double purpose but I don't need that anymore. I don't know what I was thinking with `TypeCx` I think I was trying to be clever. That's fixed now 😄
r? ``@compiler-errors``
