There are four related dataflow structs: `MaybeInitializedPlaces`,
`MaybeUninitializedPlaces`, and `EverInitializedPlaces`,
`DefinitelyInitializedPlaces`. They all have a `&Body` and a
`&MoveData<'tcx>` field. The first three use different lifetimes for the
two fields, but the last one uses the same lifetime for both.
This commit changes the first three to use the same lifetime, removing
the need for one of the lifetimes. Other structs that also lose a
lifetime as a result of this are `LivenessContext`, `LivenessResults`,
`InitializationData`.
It then does similar things in various other structs.
Add `#[warn(unreachable_pub)]` to a bunch of compiler crates
By default `unreachable_pub` identifies things that need not be `pub` and tells you to make them `pub(crate)`. But sometimes those things don't need any kind of visibility. So they way I did these was to remove the visibility entirely for each thing the lint identifies, and then add `pub(crate)` back in everywhere the compiler said it was necessary. (Or occasionally `pub(super)` when context suggested that was appropriate.) Tedious, but results in more `pub` removal.
There are plenty more crates to do but this seems like enough for a first PR.
r? `@compiler-errors`
Remove confusing `use_polonius` flag and do less cloning
The `use_polonius` flag is both redundant and confusing since every function it's propagated to also checks if `all_facts` is `Some`, the true test of whether to generate Polonius facts for Polonius or for external consumers. This PR makes that path clearer by simply doing away with the argument and handling the logic in precisely two places: where facts are populated (check for `Some`), and where `all_facts` are initialised. It also delays some statements until after that check to avoid the miniscule performance penalty of executing them when Polonius is disabled.
This also addresses `@lqd's` concern in #125652 by reducing the size of what is cloned out of Polonius facts to just the facts being added, as opposed to the entire vector of potential inputs, and added descriptive comments.
*Reviewer note*: the comments in `add_extra_drop_facts` should be inspected by a reviewer, in particular the one on [L#259](https://github.com/rust-lang/rust/compare/master...amandasystems:you-dropped-this-again?expand=1#diff-aa727290e6670264df2face84f012897878e11a70e9c8b156543cfcd9619bac3R259) in this PR, which should be trivial for someone with the right background knowledge to address.
I also included some lints I found on the way there that I couldn't help myself from addressing.
The `use_polonius` flag is both redundant and confusing since every
function it's propagated to also checks if `all_facts` is `Some`,
the true test of whether to generate Polonius facts for Polonius
or for external consumers. This PR makes that path clearer by
simply doing away with the argument and handling the logic in
precisely two places: where facts are populated (check for `Some`),
and where `all_facts` are initialised. It also delays some statements
until after that check to avoid the miniscule performance penalty
of executing them when Polonius is disabled.
This also addresses @lqd's concern in #125652 by reducing
the size of what is cloned out of Polonius facts to just the
facts being added, as opposed to the entire vector of potential
inputs, and added descriptive comments.
*Reviewer note*: the comments in [add_extra_drop_facts](85f90a4612/compiler/rustc_borrowck/src/type_check/liveness/trace.rs (L219)) should be inspected by a reviewer,
in particular the one on L#259 in this PR, which should be trivial
for someone with the right background knowledge.
I also included some minor lints I found on the way there that I
couldn't help myself from addressing.
That is, change `diagnostic_outside_of_impl` and
`untranslatable_diagnostic` from `allow` to `deny`, because more than
half of the compiler has be converted to use translated diagnostics.
This commit removes more `deny` attributes than it adds `allow`
attributes, which proves that this change is warranted.
`BorrowckErrors` stores a mix of error and non-error diags in
`buffered`. As a result, it downgrades `DiagnosticBuilder`s to
`Diagnostic`s, losing the emission guarantees, and so has to use a
`tainted_by_errors` field to record whether an error has occurred.
This commit splits `buffered` into `buffered_errors` and
`buffered_non_errors`, keeping them as `DiagnosticBuilder`s and
preserving the emission guarantees.
This also requires fixing a bunch of incorrect lifetimes on
`DiagnosticBuilder` use points.
Error codes are integers, but `String` is used everywhere to represent
them. Gross!
This commit introduces `ErrCode`, an integral newtype for error codes,
replacing `String`. It also introduces a constant for every error code,
e.g. `E0123`, and removes the `error_code!` macro. The constants are
imported wherever used with `use rustc_errors::codes::*`.
With the old code, we have three different ways to specify an error code
at a use point:
```
error_code!(E0123) // macro call
struct_span_code_err!(dcx, span, E0123, "msg"); // bare ident arg to macro call
\#[diag(name, code = "E0123")] // string
struct Diag;
```
With the new code, they all use the `E0123` constant.
```
E0123 // constant
struct_span_code_err!(dcx, span, E0123, "msg"); // constant
\#[diag(name, code = E0123)] // constant
struct Diag;
```
The commit also changes the structure of the error code definitions:
- `rustc_error_codes` now just defines a higher-order macro listing the
used error codes and nothing else.
- Because that's now the only thing in the `rustc_error_codes` crate, I
moved it into the `lib.rs` file and removed the `error_codes.rs` file.
- `rustc_errors` uses that macro to define everything, e.g. the error
code constants and the `DIAGNOSTIC_TABLES`. This is in its new
`codes.rs` file.
In #119606 I added them and used a `_mv` suffix, but that wasn't great.
A `with_` prefix has three different existing uses.
- Constructors, e.g. `Vec::with_capacity`.
- Wrappers that provide an environment to execute some code, e.g.
`with_session_globals`.
- Consuming chaining methods, e.g. `Span::with_{lo,hi,ctxt}`.
The third case is exactly what we want, so this commit changes
`DiagnosticBuilder::foo_mv` to `DiagnosticBuilder::with_foo`.
Thanks to @compiler-errors for the suggestion.
Because it takes an error code after the span. This avoids the confusing
overlap with the `DiagCtxt::struct_span_err` method, which doesn't take
an error code.
`IntoDiagnostic` defaults to `ErrorGuaranteed`, because errors are the
most common diagnostic level. It makes sense to do likewise for the
closely-related (and much more widely used) `DiagnosticBuilder` type,
letting us write `DiagnosticBuilder<'a, ErrorGuaranteed>` as just
`DiagnosticBuilder<'a>`. This cuts over 200 lines of code due to many
multi-line things becoming single line things.
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.
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>
`MultiSpan` contains labels, which are more complicated with the
introduction of diagnostic translation and will use types from
`rustc_errors` - however, `rustc_errors` depends on `rustc_span` so
`rustc_span` cannot use types like `DiagnosticMessage` without
dependency cycles. Introduce a new `rustc_error_messages` crate that can
contain `DiagnosticMessage` and `MultiSpan`.
Signed-off-by: David Wood <david.wood@huawei.com>
