Tweak unclosed generics errors
Remove unnecessary span label for parse errors that already have a suggestion.
Provide structured suggestion to close generics in more cases.
Tweak `.clone()` suggestion to work in more cases
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() {}
| ++++++++++++++++++++++++++++++ +
```
When encountering a move error, look for implementations of `Clone` for the moved type. If there is one, check if all its obligations are met. If they are, we suggest cloning without caveats. If they aren't, we suggest cloning while mentioning the unmet obligations, potentially suggesting `#[derive(Clone)]` when appropriate.
```
error[E0507]: cannot move out of a shared reference
--> $DIR/suggest-clone-when-some-obligation-is-unmet.rs:20:28
|
LL | let mut copy: Vec<U> = map.clone().into_values().collect();
| ^^^^^^^^^^^ ------------- value moved due to this method call
| |
| move occurs because value has type `HashMap<T, U, Hash128_1>`, which does not implement the `Copy` trait
|
note: `HashMap::<K, V, S>::into_values` takes ownership of the receiver `self`, which moves value
--> $SRC_DIR/std/src/collections/hash/map.rs:LL:COL
help: you could `clone` the value and consume it, if the `Hash128_1: Clone` trait bound could be satisfied
|
LL | let mut copy: Vec<U> = <HashMap<T, U, Hash128_1> as Clone>::clone(&map.clone()).into_values().collect();
| ++++++++++++++++++++++++++++++++++++++++++++ +
help: consider annotating `Hash128_1` with `#[derive(Clone)]`
|
LL + #[derive(Clone)]
LL | pub struct Hash128_1;
|
```
Fix#109429.
When encountering multiple mutable borrows, suggest cloning and adding
derive annotations as needed.
```
error[E0596]: cannot borrow `sm.x` as mutable, as it is behind a `&` reference
--> $DIR/accidentally-cloning-ref-borrow-error.rs:32:9
|
LL | foo(&mut sm.x);
| ^^^^^^^^^ `sm` is a `&` reference, so the data it refers to cannot be borrowed as mutable
|
help: `Str` doesn't implement `Clone`, so this call clones the reference `&Str`
--> $DIR/accidentally-cloning-ref-borrow-error.rs:31:21
|
LL | let mut sm = sr.clone();
| ^^^^^^^
help: consider annotating `Str` with `#[derive(Clone)]`
|
LL + #[derive(Clone)]
LL | struct Str {
|
help: consider specifying this binding's type
|
LL | let mut sm: &mut Str = sr.clone();
| ++++++++++
```
Fix#34629. Fix#76643. Fix#91532.
Structured `use` suggestion on privacy error
When encoutering a privacy error on an item through a re-export that is accessible in an alternative path, provide a structured suggestion with that path.
```
error[E0603]: module import `mem` is private
--> $DIR/private-std-reexport-suggest-public.rs:4:14
|
LL | use foo::mem;
| ^^^ private module import
|
note: the module import `mem` is defined here...
--> $DIR/private-std-reexport-suggest-public.rs:8:9
|
LL | use std::mem;
| ^^^^^^^^
note: ...and refers to the module `mem` which is defined here
--> $SRC_DIR/std/src/lib.rs:LL:COL
|
= note: you could import this
help: import `mem` through the re-export
|
LL | use std::mem;
| ~~~~~~~~
```
Fix#42909.
When encoutering a privacy error on an item through a re-export that is
accessible in an alternative path, provide a structured suggestion with
that path.
```
error[E0603]: module import `mem` is private
--> $DIR/private-std-reexport-suggest-public.rs:4:14
|
LL | use foo::mem;
| ^^^ private module import
|
note: the module import `mem` is defined here...
--> $DIR/private-std-reexport-suggest-public.rs:8:9
|
LL | use std::mem;
| ^^^^^^^^
note: ...and refers to the module `mem` which is defined here
--> $SRC_DIR/std/src/lib.rs:LL:COL
|
= note: you could import this
help: import `mem` through the re-export
|
LL | use std::mem;
| ~~~~~~~~
```
Fix#42909.
When encountering multiple mutable borrows, suggest cloning and adding
derive annotations as needed.
```
error[E0596]: cannot borrow `sm.x` as mutable, as it is behind a `&` reference
--> $DIR/accidentally-cloning-ref-borrow-error.rs:32:9
|
LL | foo(&mut sm.x);
| ^^^^^^^^^ `sm` is a `&` reference, so the data it refers to cannot be borrowed as mutable
|
help: `Str` doesn't implement `Clone`, so this call clones the reference `&Str`
--> $DIR/accidentally-cloning-ref-borrow-error.rs:31:21
|
LL | let mut sm = sr.clone();
| ^^^^^^^
help: consider annotating `Str` with `#[derive(Clone)]`
|
LL + #[derive(Clone)]
LL | struct Str {
|
help: consider specifying this binding's type
|
LL | let mut sm: &mut Str = sr.clone();
| ++++++++++
```
```
error[E0596]: cannot borrow `*inner` as mutable, as it is behind a `&` reference
--> $DIR/issue-91206.rs:14:5
|
LL | inner.clear();
| ^^^^^ `inner` is a `&` reference, so the data it refers to cannot be borrowed as mutable
|
help: you can `clone` the `Vec<usize>` value and consume it, but this might not be your desired behavior
--> $DIR/issue-91206.rs:11:17
|
LL | let inner = client.get_inner_ref();
| ^^^^^^^^^^^^^^^^^^^^^^
help: consider specifying this binding's type
|
LL | let inner: &mut Vec<usize> = client.get_inner_ref();
| +++++++++++++++++
```
When encountering a case where `let x: T = (val: &T).clone();` and
`T: !Clone`, already mention that the reference is being cloned. We now
also suggest `#[derive(Clone)]` not only on `T` but also on type
parameters to satisfy blanket implementations.
```
error[E0308]: mismatched types
--> $DIR/assignment-of-clone-call-on-ref-due-to-missing-bound.rs:17:39
|
LL | let mut x: HashSet<Day> = v.clone();
| ------------ ^^^^^^^^^ expected `HashSet<Day>`, found `&HashSet<Day>`
| |
| expected due to this
|
= note: expected struct `HashSet<Day>`
found reference `&HashSet<Day>`
note: `HashSet<Day>` does not implement `Clone`, so `&HashSet<Day>` was cloned instead
--> $DIR/assignment-of-clone-call-on-ref-due-to-missing-bound.rs:17:39
|
LL | let mut x: HashSet<Day> = v.clone();
| ^
= help: `Clone` is not implemented because the trait bound `Day: Clone` is not satisfied
help: consider annotating `Day` with `#[derive(Clone)]`
|
LL + #[derive(Clone)]
LL | enum Day {
|
```
Case taken from # #41825.
When encountering a move error, look for implementations of `Clone` for
the moved type. If there is one, check if all its obligations are met.
If they are, we suggest cloning without caveats. If they aren't, we
suggest cloning while mentioning the unmet obligations, potentially
suggesting `#[derive(Clone)]` when appropriate.
```
error[E0507]: cannot move out of a shared reference
--> $DIR/suggest-clone-when-some-obligation-is-unmet.rs:20:28
|
LL | let mut copy: Vec<U> = map.clone().into_values().collect();
| ^^^^^^^^^^^ ------------- value moved due to this method call
| |
| move occurs because value has type `HashMap<T, U, Hash128_1>`, which does not implement the `Copy` trait
|
note: `HashMap::<K, V, S>::into_values` takes ownership of the receiver `self`, which moves value
--> $SRC_DIR/std/src/collections/hash/map.rs:LL:COL
help: you could `clone` the value and consume it, if the `Hash128_1: Clone` trait bound could be satisfied
|
LL | let mut copy: Vec<U> = <HashMap<T, U, Hash128_1> as Clone>::clone(&map.clone()).into_values().collect();
| ++++++++++++++++++++++++++++++++++++++++++++ +
help: consider annotating `Hash128_1` with `#[derive(Clone)]`
|
LL + #[derive(Clone)]
LL | pub struct Hash128_1;
|
```
Fix#109429.
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.
[rustdoc] Don't generate the "Fields" heading if there is no field displayed
Fixes https://github.com/rust-lang/rust/issues/118195.
If no field is displayed, we should not generate the `Fields` heading in enum struct variants.
r? ``@notriddle``
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.
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
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
[rustdoc] Add highlighting for comments in items declaration
Fixes#117555.
So after the discussion in https://github.com/rust-lang/rust/pull/117643, the outcome was that having the comments in the item declaration at the same level (in term of color) as the rest of the code was actually a bit distracting and could be improved.
The current highlighting color for comments is "lighter" than the rest and I think it fits perfectly to improve the current situation. With this, we now have different "levels" which makes it easier to read and filter out what we want when reading the items declaration.
Here's a screenshot:
r? `@notriddle`
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`
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.
move packed-struct tests into packed/ folder
We already have a bunch of other tests named `packed/packed-struct*`, no reason to have these two tests be separate.
Add more information to StableMIR Instance
Allow stable MIR users to retrieve an instance function signature, the index for a VTable instance and more information about its underlying definition.
These are needed to properly interpret function calls, either via VTable or direct calls. The `CrateDef` implementation will also allow users to emit diagnostic messages.
I also fixed a few issues that we had identified before with how we were retrieving body of things that may not have a body available.
Handle recursion limit for subtype and well-formed predicates
Adds a recursion limit check for subtype predicates and well-formed predicates.
`-Ztrait-solver=next` currently panics with unimplemented for these cases.
These cases are arguably bugs in the occurs check but:
- I could not find a simple way to fix the occurs check
- There should still be a recursion limit check to prevent hangs anyway.
closes#117151
r? types
Centralize live loans maintenance to fix scope differences due to liveness
As found in the recent [polonius crater run](https://github.com/rust-lang/rust/pull/117593#issuecomment-1801398892), NLLs and the location-insensitive polonius computed different scopes on some specific CFG shapes, e.g. the following.
I had missed that liveness data was pushed from different sources than just the liveness computation: there are a few places that do this -- and some of them may be unneeded or at the very least untested, as no tests changed when I tried removing some of them.
Here, `_6` is e.g. dead on entry to `bb2[0]` during `liveness::trace`, but its regions will be marked as live later during "constraint generation" (which I plan to refactor away and put in the liveness module soon). This should cause the inflowing loans to be marked live, but they were only computed in `liveness::trace`.
Therefore, this PR moves live loan maintenance to `LivenessValues`, so that the various places pushing liveness data will all also update live loans at the same time -- except for promoteds which I don't believe need them, and their liveness handling is already interesting/peculiar.
All the regressions I saw in the initial crater run were related to this kind of shapes, and this change did fix all of them on the [next run](https://github.com/rust-lang/rust/pull/117593#issuecomment-1826132145).
r? `@matthewjasper`
(This will conflict with #117880 but whichever lands first is fine by me, the end goal is the same for both)
Restore `#![no_builtins]` crates participation in LTO.
After #113716, we can make `#![no_builtins]` crates participate in LTO again.
`#![no_builtins]` with LTO does not result in undefined references to the error. I believe this type of issue won't happen again.
Fixes#72140. Fixes#112245. Fixes#110606. Fixes#105734. Fixes#96486. Fixes#108853. Fixes#108893. Fixes#78744. Fixes#91158. Fixes https://github.com/rust-lang/cargo/issues/10118. Fixes https://github.com/rust-lang/compiler-builtins/issues/347.
The `nightly-2023-07-20` version does not always reproduce problems due to changes in compiler-builtins, core, and user code. That's why this issue recurs and disappears.
Some issues were not tested due to the difficulty of reproducing them.
r? pnkfelix
cc `@bjorn3` `@japaric` `@alexcrichton` `@Amanieu`
