When a binding is declared without a value, borrowck verifies that all
codepaths have *one* assignment to them to initialize them fully. If
there are any cases where a condition can be met that leaves the binding
uninitialized or we attempt to initialize a field of an unitialized
binding, we emit E0381.
We now look at all the statements that initialize the binding, and use
them to explore branching code paths that *don't* and point at them. If
we find *no* potential places where an assignment to the binding might
be missing, we display the spans of all the existing initializers to
provide some context.
cleanup mir visitor for `rustc::pass_by_value`
by changing `& $($mutability)?` to `$(& $mutability)?`
I also did some formatting changes because I started doing them for the visit methods I changed and then couldn't get myself to stop xx, I hope that's still fairly easy to review.
In NLL, when we are promoting a bound out from a closure,
if we have a requirement that `T: 'a` where `'a` is in a
higher universe, we were previously ignoring that, which is
totally wrong. We should be promoting those constraints to `'static`,
since universes are not expressible across closure boundaries.
translation: lint fix + more migration
- Unfortunately, the diagnostic lints are very broken and trigger much more often than they should. This PR corrects the conditional which checks if the function call being made is to a diagnostic function so that it returns in every intended case.
- The `rustc_lint_diagnostics` attribute is used by the diagnostic translation/struct migration lints to identify calls where non-translatable diagnostics or diagnostics outwith impls are being created. Any function used in creating a diagnostic should be annotated with this attribute so this PR adds the attribute to many more functions.
- Port the diagnostics from the `rustc_privacy` crate and enable the lints for that crate.
r? ``@compiler-errors``
The `rustc_lint_diagnostics` attribute is used by the diagnostic
translation/struct migration lints to identify calls where
non-translatable diagnostics or diagnostics outwith impls are being
created. Any function used in creating a diagnostic should be annotated
with this attribute so this commit adds the attribute to many more
functions.
Signed-off-by: David Wood <david.wood@huawei.com>
fix universes in the NLL type tests
In the NLL code, we were not accommodating universes in the
`type_test` logic.
Fixes#98095.
r? `@compiler-errors`
This breaks some tests, however, so the purpose of this branch is more explanatory and perhaps to do a crater run.
Create elided lifetime parameters for function-like types
Split from https://github.com/rust-lang/rust/pull/97720
This PR refactor lifetime generic parameters in bare function types and parenthesized traits to introduce the additional required lifetimes as fresh parameters in a `for<>` bound.
This PR does the same to lifetimes appearing in closure signatures, and as-if introducing `for<>` bounds on closures (without the associated change in semantics).
r? `@petrochenkov`
Fix erroneous span for borrowck error
I am not confident that this is the correct fix, but it does the job. Open to suggestions for a real fix instead.
Fixes#97997
The issue is that we pass a [dummy location](https://doc.rust-lang.org/nightly/nightly-rustc/src/rustc_middle/mir/visit.rs.html#302) when type-checking the ["required consts"](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/mir/struct.Body.html#structfield.required_consts) that are needed by the MIR body during borrowck. This means that when we fail to evaluate the constant, we use the span of `bb0[0]`, instead of the actual span of the constant.
There are quite a few other places that use `START_BLOCK.start_location()`, `Location::START`, etc. when calling for a random/unspecified `Location` value. This is because, unlike (for example) `Span`, we don't have a dummy/miscellaneous value to use instead. I would appreciate guidance (either in this PR, or a follow-up) on what needs to be done to clean this up in general.
Make `ExprKind::Closure` a struct variant.
Simple refactor since we both need it to introduce additional fields in `ExprKind::Closure`.
r? ``@Aaron1011``
And likewise for the `Const::val` method.
Because its type is called `ConstKind`. Also `val` is a confusing name
because `ConstKind` is an enum with seven variants, one of which is
called `Value`. Also, this gives consistency with `TyS` and `PredicateS`
which have `kind` fields.
The commit also renames a few `Const` variables from `val` to `c`, to
avoid confusion with the `ConstKind::Value` variant.
Compute `is_late_bound_map` query separately from lifetime resolution
This query is actually very simple, and is only useful for functions and method. It can be computed directly by fetching the HIR, with no need to embed it within the lifetime resolution visitor.
Based on https://github.com/rust-lang/rust/pull/96296
