Rollup of 4 pull requests
Successful merges:
- #124519 (adapt a codegen test for llvm 19)
- #124524 (Add StaticForeignItem and use it on ForeignItemKind)
- #124540 (Give proof tree visitors the ability to instantiate nested goals directly)
- #124543 (codegen tests: Tolerate `range()` qualifications in enum tests)
r? `@ghost`
`@rustbot` modify labels: rollup
Add StaticForeignItem and use it on ForeignItemKind
This is in preparation for unsafe extern blocks that adds a safe variant for functions inside extern blocks.
r? `@oli-obk`
cc `@compiler-errors`
coverage: Replace boolean options with a `CoverageLevel` enum
After #123409, and some discussion at https://github.com/rust-lang/rust/issues/79649#issuecomment-2042093553 and #124120, it became clear to me that we should have a unified concept of “coverage level”, instead of having several separate boolean flags that aren't actually independent.
This PR therefore introduces a `CoverageLevel` enum, to replace the existing boolean flags for `branch` and `mcdc`.
The `no-branch` value (for `-Zcoverage-options`) has been renamed to `block`, instructing the compiler to only instrument for block coverage, with no branch coverage or MD/DC instrumentation.
`@rustbot` label +A-code-coverage
cc `@ZhuUx` `@Lambdaris` `@RenjiSann`
Add a note to the ArbitraryExpressionInPattern error
The current "arbitrary expressions aren't allowed in patterns" error is confusing, as it fires for code where it *looks* like a pattern but the compiler still treats it as an expression. That this is due to the `:expr` fragment specifier forcing the expression-ness property on the code.
In the test suite, the "arbitrary expressions aren't allowed in patterns" error can only be found in combination with macro_rules macros that force expression-ness of their content, namely via `:expr` metavariables. I also can't come up with cases where there would be an expression instead of a pattern, so I think it's always coming from an `:expr`.
In order to make the error less confusing, this adds a note explaining the weird `:expr` fragment behaviour.
Fixes#99380
[Refactor] Rename `Lint` and `LintGroup`'s `is_loaded` to `is_externally_loaded`
The field being named `is_loaded` was very confusing. Turns out it's true for lints that are registered by external tools like Clippy (I had to look at https://github.com/rust-lang/rust/pull/116412 to know what the variable meant). So I renamed `is_loaded` to `is_externally_loaded` and added some docs.
Mark unions non-const-propagatable in `KnownPanicsLint` without calling layout
Fixes#123710
The ICE occurs during the layout calculation of the union `InvalidTag` in #123710 because the following assert fails:5fe8b697e7/compiler/rustc_abi/src/layout.rs (L289-L292)
The layout calculation is invoked by `KnownPanicsLint` when it is trying to figure out which locals it can const prop. Since `KnownPanicsLint` is never actually going to const props unions thanks to PR https://github.com/rust-lang/rust/pull/121628 there's no point calling layout to check if it can. So in this fix I skip the call to layout and just mark the local non-const propagatable if it is a union.
Fix#124478 - offset_of! returns a temporary
This was due to the must_use() call. Adding HIR's `OffsetOf` to the must_use checking within the compiler avoids this issue while maintaining the lint output.
Fixes#124478. `@tgross35`
Do not ICE on invalid consts when walking mono-reachable blocks
The `bug!` here was written under the logic of "this condition is impossible, right?" except that of course, if the compiler is given code that results in an compile error, then the situation is possible.
So now we just direct errors into the already-existing path for when we can't do a mono-time optimization.
Fix ICE on invalid const param types
Fixes ICE #123863 which occurs because the const param has a type which is not a `bool`, `char` or an integral type.
The ICEing code path begins here in `typeck_with_fallback`: cb3752d20e/compiler/rustc_hir_typeck/src/lib.rs (L167)
The `fallback` invokes the `type_of` query and that eventually ends up calling `ct_infer` from the lowering code over here:
cb3752d20e/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs (L561) and `ct_infer` ICEs at this location: cb3752d20e/compiler/rustc_hir_analysis/src/collect.rs (L392)
To fix the ICE it I'm triggering a `span_delayed_bug` before we hit `ct_infer` if the type of the const param is not one of the supported types
### Edit
On `@lcnr's` suggestion I've changed the approach to not let `ReStatic` region hit the `bug!` in `ct_infer` instead of triggering a `span_delayed_bug`.
Fix substitution parts having a shifted underline in some cases
If two suggestions parts are side by side, the underline's offset:
(WIP PR as an example, not yet pushed)
```
error: expected a pattern, found an expression
--> ./main.rs:4:9
|
4 | 1 + 2 => 3
| ^^^^^ arbitrary expressions are not allowed in patterns
|
help: check the value in an arm guard
|
4 | n if n == 1 + 2 => 3
| ~ +++++++++++++
```
The emitter didn't take into account that the string had shrunk/grown if two substitution parts were side-by-side (surprisingly, there was only one case in the ui testsuite.)
```
help: check the value in an arm guard
|
4 | n if n == 1 + 2 => 3
| ~ +++++++++++++
```
``@rustbot`` label +A-suggestion-diagnostics
ast: Generalize item kind visiting
And avoid duplicating logic for visiting `Item`s with different kinds (regular, associated, foreign).
The diff is better viewed with whitespace ignored.
`obligations_for_self_ty`: use `ProofTreeVisitor` for nested goals
As always, dealing with proof trees continues to be a hacked together mess. After this PR and #124380 the only remaining blocker for core is https://github.com/rust-lang/trait-system-refactor-initiative/issues/90. There is also a `ProofTreeVisitor` issue causing an ICE when compiling `alloc` which I will handle in a separate PR. This issue likely affects coherence diagnostics more generally.
The core idea is to extend the proof tree visitor to support visiting nested candidates without using a `probe`. We then simply recurse into nested candidates if they are the only potentially applicable candidate for a given goal and check whether the self type matches the expected one.
For that to work, we need to improve `CanonicalState` to also handle unconstrained inference variables created inside of the trait solver. This is done by extending the `var_values` of `CanoncalState` with each fresh inference variables. Furthermore, we also store the state of all inference variables at the end of each probe. When recursing into `InspectCandidates` we then unify the values of all these states.
r? `@compiler-errors`
uses a `ProofTreeVisitor` to look into nested
goals when looking at the pending obligations
during hir typeck. Used by closure signature
inference, coercion, and for async functions.
`-Z debug-macros` is "stabilized" by enabling it by default and removing.
`-Z collapse-macro-debuginfo` is stabilized as `-C collapse-macro-debuginfo`.
It now supports all typical boolean values (`parse_opt_bool`) in addition to just yes/no.
Default value of `collapse_debuginfo` was changed from `false` to `external` (i.e. collapsed if external, not collapsed if local).
`#[collapse_debuginfo]` attribute without a value is no longer supported to avoid guessing the default.
Don't ICE when `codegen_select_candidate` returns ambiguity in new solver
Because we merge identical candidates, we may have >1 impl candidate to in `codegen_select_error` but *not* have a trait error.
r? lcnr
Detect borrow error involving sub-slices and suggest `split_at_mut`
```
error[E0499]: cannot borrow `foo` as mutable more than once at a time
--> $DIR/suggest-split-at-mut.rs:13:18
|
LL | let a = &mut foo[..2];
| --- first mutable borrow occurs here
LL | let b = &mut foo[2..];
| ^^^ second mutable borrow occurs here
LL | a[0] = 5;
| ---- first borrow later used here
|
= help: use `.split_at_mut(position)` or similar method to obtain two mutable non-overlapping sub-slices
```
Address most of #58792.
For follow up work, we should emit a structured suggestion for cases where we can identify the exact `let (a, b) = foo.split_at_mut(2);` call that is needed.
```
error[E0499]: cannot borrow `foo` as mutable more than once at a time
--> $DIR/suggest-split-at-mut.rs:13:18
|
LL | let a = &mut foo[..2];
| --- first mutable borrow occurs here
LL | let b = &mut foo[2..];
| ^^^ second mutable borrow occurs here
LL | a[0] = 5;
| ---- first borrow later used here
|
= help: use `.split_at_mut(position)` or similar method to obtain two mutable non-overlapping sub-slices
```
Address most of #58792.
For follow up work, we should emit a structured suggestion for cases where we can identify the exact `let (a, b) = foo.split_at_mut(2);` call that is needed.
