When going through auto-deref, the `<T as Clone>` impl sometimes needs
to be specified for rustc to actually clone the value and not the
reference.
```
error[E0507]: cannot move out of dereference of `S`
--> $DIR/needs-clone-through-deref.rs:15:18
|
LL | for _ in self.clone().into_iter() {}
| ^^^^^^^^^^^^ ----------- value moved due to this method call
| |
| move occurs because value has type `Vec<usize>`, which does not implement the `Copy` trait
|
note: `into_iter` takes ownership of the receiver `self`, which moves value
--> $SRC_DIR/core/src/iter/traits/collect.rs:LL:COL
help: you can `clone` the value and consume it, but this might not be your desired behavior
|
LL | for _ in <Vec<usize> as Clone>::clone(&self.clone()).into_iter() {}
| ++++++++++++++++++++++++++++++ +
```
CC #109429.
rustc: Harmonize `DefKind` and `DefPathData`
Follow up to https://github.com/rust-lang/rust/pull/118188.
`DefPathData::(ClosureExpr,ImplTrait)` are renamed to match `DefKind::(Closure,OpaqueTy)`.
`DefPathData::ImplTraitAssocTy` is replaced with `DefPathData::TypeNS(kw::Empty)` because both correspond to `DefKind::AssocTy`.
It's possible that introducing `(DefKind,DefPathData)::AssocOpaqueTy` instead could be a better solution, but that would be a much more invasive change.
Const generic parameters introduced for effects are moved from `DefPathData::TypeNS` to `DefPathData::ValueNS`, because constants are values.
`DefPathData` is no longer passed to `create_def` functions to avoid redundancy.
more targeted errors when extern types end up in places they should not
Cc https://github.com/rust-lang/rust/issues/115709 -- this does not fix that bug but it makes the panics less obscure and makes it more clear that this is a deeper issue than just a little codegen oversight. (In https://github.com/rust-lang/rust/pull/116115 we decided we'd stick to causing ICEs here for now, rather than nicer errors. We can't currently show any errors pre-mono and probably we don't want post-mono checks when this gets stabilized anyway.)
Restrict what symbols can be used in `#[diagnostic::on_unimplemented]` format strings
This commit restricts what symbols can be used in a format string for any option of the `diagnostic::on_unimplemented` attribute. We previously allowed all the ad-hoc options supported by the internal `#[rustc_on_unimplemented]` attribute. For the stable attribute we only want to support generic parameter names and `{Self}` as parameters. For any other parameter an warning is emitted and the parameter is replaced by the literal parameter string, so for example `{integer}` turns into `{integer}`. This follows the general design of attributes in the `#[diagnostic]` attribute namespace, that any syntax "error" is treated as warning and subsequently ignored.
r? `@compiler-errors`
This commit restricts what symbols can be used in a format string for
any option of the `diagnostic::on_unimplemented` attribute. We
previously allowed all the ad-hoc options supported by the internal
`#[rustc_on_unimplemented]` attribute. For the stable attribute we only
want to support generic parameter names and `{Self}` as parameters. For
any other parameter an warning is emitted and the parameter is replaced
by the literal parameter string, so for example `{integer}` turns into
`{integer}`. This follows the general design of attributes in the
`#[diagnostic]` attribute namespace, that any syntax "error" is treated
as warning and subsequently ignored.
This is weird: `HandlerInner::emit` calls
`HandlerInner::emit_diagnostic`, but only after doing a
`treat-err-as-bug` check. Which is fine, *except* that there are
multiple others paths for an `Error` or `Fatal` diagnostic to be passed
to `HandlerInner::emit_diagnostic` without going through
`HandlerInner::emit`, e.g. `Handler::span_err` call
`Handler::emit_diag_at_span`, which calls `emit_diagnostic`.
So that suggests that the coverage for `treat-err-as-bug` is incomplete.
This commit removes `HandlerInner::emit` and moves the
`treat-err-as-bug` check to `HandlerInner::emit_diagnostic`, so it
cannot by bypassed.
`Handler` is a wrapper around `HanderInner`. Some functions on
on `Handler` just forward to the samed-named functions on
`HandlerInner`.
This commit removes as many of those as possible, implementing functions
on `Handler` where possible, to avoid the boilerplate required for
forwarding. The commit is moderately large but it's very mechanical.
These impls are all needed for just a single `IntoDiagnostic` type, not
a family of them.
Note that `ErrorGuaranteed` is the default type parameter for
`IntoDiagnostic`.
Exhaustiveness: allocate memory better
Exhaustiveness is a recursive algorithm that allocates a bunch of slices at every step. Let's see if I can improve performance by improving allocations.
Already just using `Vec::with_capacity` is showing impressive improvements on my local measurements.
r? `@ghost`
Currently, `Handler::fatal` returns `FatalError`. But `Session::fatal`
returns `!`, because it calls `Handler::fatal` and then calls `raise` on
the result. This inconsistency is unfortunate.
This commit changes `Handler::fatal` to do the `raise` itself, changing
its return type to `!`. This is safe because there are only two calls to
`Handler::fatal`, one in `rustc_session` and one in
`rustc_codegen_cranelift`, and they both call `raise` on the result.
`HandlerInner::fatal` still returns `FatalError`, so I renamed it
`fatal_no_raise` to emphasise the return type difference.
miri: support 'promising' alignment for symbolic alignment check
Then use that ability in `slice::align_to`, so that even with `-Zmiri-symbolic-alignment-check`, it no longer has to return spuriously empty "middle" parts.
Fixes https://github.com/rust-lang/miri/issues/3068
Rollup of 3 pull requests
Successful merges:
- #117869 ([rustdoc] Add highlighting for comments in items declaration)
- #118525 (coverage: Skip spans that can't be un-expanded back to the function body)
- #118574 (rustc_session: Address all `rustc::potential_query_instability` lints)
r? `@ghost`
`@rustbot` modify labels: rollup
rustc_session: Address all `rustc::potential_query_instability` lints
Instead of allowing `rustc::potential_query_instability` on the whole crate we go over each lint and allow it individually if it is safe to do. Turns out all instances were safe to allow in this crate.
Part of #84447 which is **E-help-wanted**.
coverage: Skip spans that can't be un-expanded back to the function body
When we extract coverage spans from MIR, we try to "un-expand" them back to spans that are inside the function's body span.
In cases where that doesn't succeed, the current code just swaps in the entire body span instead. But that tends to result in coverage spans that are completely unrelated to the control flow of the affected code, so it's better to just discard those spans.
---
Extracted from #118305, since this is a general improvement that isn't specific to branch coverage.
---
`@rustbot` label +A-code-coverage
Provide structured suggestion for type mismatch in loop
We currently provide only a `help` message, this PR introduces the last two structured suggestions instead:
```
error[E0308]: mismatched types
--> $DIR/issue-98982.rs:2:5
|
LL | fn foo() -> i32 {
| --- expected `i32` because of return type
LL | / for i in 0..0 {
LL | | return i;
LL | | }
| |_____^ expected `i32`, found `()`
|
note: the function expects a value to always be returned, but loops might run zero times
--> $DIR/issue-98982.rs:2:5
|
LL | for i in 0..0 {
| ^^^^^^^^^^^^^ this might have zero elements to iterate on
LL | return i;
| -------- if the loop doesn't execute, this value would never get returned
help: return a value for the case when the loop has zero elements to iterate on
|
LL ~ }
LL ~ /* `i32` value */
|
help: otherwise consider changing the return type to account for that possibility
|
LL ~ fn foo() -> Option<i32> {
LL | for i in 0..0 {
LL ~ return Some(i);
LL ~ }
LL ~ None
|
```
Fix#98982.
Report errors in jobserver inherited through environment variables
This pr attempts to catch situations, when jobserver exists, but is not being inherited.
r? `@petrochenkov`
Instead of allowing `rustc::potential_query_instability` on the whole
crate we go over each lint and allow it individually if it is safe to
do. Turns out all instances were safe to allow in this crate.
`DefPathData::(ClosureExpr,ImplTrait)` are renamed to match `DefKind::(Closure,OpaqueTy)`.
`DefPathData::ImplTraitAssocTy` is replaced with `DefPathData::TypeNS(kw::Empty)` because both correspond to `DefKind::AssocTy`.
It's possible that introducing `(DefKind,DefPathData)::AssocOpaqueTy` could be a better solution, but that would be a much more invasive change.
Const generic parameters introduced for effects are moved from `DefPathData::TypeNS` to `DefPathData::ValueNS`, because constants are values.
`DefPathData` is no longer passed to `create_def` functions to avoid redundancy.