Make `DefiningAnchor::Bind` only store the opaque types that may be constrained, instead of the current infcx root item.
This makes `Bind` almost always be empty, so we can start forwarding it to queries, allowing us to remove `Bubble` entirely (not done in this PR)
The only behaviour change is in diagnostics.
r? `@lcnr` `@compiler-errors`
Rollup of 15 pull requests
Successful merges:
- #116791 (Allow codegen backends to opt-out of parallel codegen)
- #116793 (Allow targets to override default codegen backend)
- #117458 (LLVM Bitcode Linker: A self contained linker for nvptx and other targets)
- #119385 (Fix type resolution of associated const equality bounds (take 2))
- #121438 (std support for wasm32 panic=unwind)
- #121893 (Add tests (and a bit of cleanup) for interior mut handling in promotion and const-checking)
- #122080 (Clarity improvements to `DropTree`)
- #122152 (Improve diagnostics for parenthesized type arguments)
- #122166 (Remove the unused `field_remapping` field from `TypeLowering`)
- #122249 (interpret: do not call machine read hooks during validation)
- #122299 (Store backtrace for `must_produce_diag`)
- #122318 (Revision-related tweaks for next-solver tests)
- #122320 (Use ptradd for vtable indexing)
- #122328 (unix_sigpipe: Replace `inherit` with `sig_dfl` in syntax tests)
- #122330 (bootstrap readme: fix, improve, update)
r? `@ghost`
`@rustbot` modify labels: rollup
This improves parallel rustc parallelism by avoiding the bottleneck after each individual `par_body_owners` (because it needs to wait for queries to finish, so if there is one long running one, a lot of cores will be idle while waiting for the single query).
Provide more suggestions on invalid equality where bounds
```
error: equality constraints are not yet supported in `where` clauses
--> $DIR/equality-bound.rs:50:9
|
LL | IntoIterator::Item = A
| ^^^^^^^^^^^^^^^^^^^^^^ not supported
|
= note: see issue #20041 <https://github.com/rust-lang/rust/issues/20041> for more information
help: if `IntoIterator::Item` is an associated type you're trying to set, use the associated type binding syntax
|
LL ~ fn from_iter<T: IntoIterator<Item = A>>(_: T) -> Self
LL ~
|
error: equality constraints are not yet supported in `where` clauses
--> $DIR/equality-bound.rs:63:9
|
LL | T::Item = A
| ^^^^^^^^^^^ not supported
|
= note: see issue #20041 <https://github.com/rust-lang/rust/issues/20041> for more information
help: if `IntoIterator::Item` is an associated type you're trying to set, use the associated type binding syntax
|
LL ~ fn from_iter<T: IntoIterator<Item = A>>(_: T) -> Self
LL ~
|
```
Fix#68982.
Harmonize `AsyncFn` implementations, make async closures conditionally impl `Fn*` traits
This PR implements several changes to the built-in and libcore-provided implementations of `Fn*` and `AsyncFn*` to address two problems:
1. async closures do not implement the `Fn*` family traits, leading to breakage: https://crater-reports.s3.amazonaws.com/pr-120361/index.html
2. *references* to async closures do not implement `AsyncFn*`, as a consequence of the existing blanket impls of the shape `AsyncFn for F where F: Fn, F::Output: Future`.
In order to fix (1.), we implement `Fn` traits appropriately for async closures. It turns out that async closures can:
* always implement `FnOnce`, meaning that they're drop-in compatible with `FnOnce`-bound combinators like `Option::map`.
* conditionally implement `Fn`/`FnMut` if they have no captures, which means that existing usages of async closures should *probably* work without breakage (crater checking this: https://github.com/rust-lang/rust/pull/120712#issuecomment-1930587805).
In order to fix (2.), we make all of the built-in callables implement `AsyncFn*` via built-in impls, and instead adjust the blanket impls for `AsyncFn*` provided by libcore to match the blanket impls for `Fn*`.
```
error: equality constraints are not yet supported in `where` clauses
--> $DIR/equality-bound.rs:50:9
|
LL | IntoIterator::Item = A,
| ^^^^^^^^^^^^^^^^^^^^^^ not supported
|
= note: see issue #20041 <https://github.com/rust-lang/rust/issues/20041> for more information
help: if `IntoIterator::Item` is an associated type you're trying to set, use the associated type binding syntax
|
LL ~ fn from_iter<T: IntoIterator<Item = A>>(_: T) -> Self
LL | where
LL ~
|
error: equality constraints are not yet supported in `where` clauses
--> $DIR/equality-bound.rs:63:9
|
LL | T::Item = A,
| ^^^^^^^^^^^ not supported
|
= note: see issue #20041 <https://github.com/rust-lang/rust/issues/20041> for more information
help: if `IntoIterator::Item` is an associated type you're trying to set, use the associated type binding syntax
|
LL ~ fn from_iter<T: IntoIterator<Item = A>>(_: T) -> Self
LL | where
LL ~
|
```
Fix#68982.
Account for non-overlapping unmet trait bounds in suggestion
When a method not found on a type parameter could have been provided by any
of multiple traits, suggest each trait individually, instead of a single
suggestion to restrict the type parameter with *all* of them.
Before:
```
error[E0599]: the method `cmp` exists for reference `&T`, but its trait bounds were not satisfied
--> $DIR/method-on-unbounded-type-param.rs:5:10
|
LL | (&a).cmp(&b)
| ^^^ method cannot be called on `&T` due to unsatisfied trait bounds
|
= note: the following trait bounds were not satisfied:
`T: Ord`
which is required by `&T: Ord`
`&T: Iterator`
which is required by `&mut &T: Iterator`
`T: Iterator`
which is required by `&mut T: Iterator`
help: consider restricting the type parameters to satisfy the trait bounds
|
LL | fn g<T>(a: T, b: T) -> std::cmp::Ordering where T: Iterator, T: Ord {
| +++++++++++++++++++++++++
```
After:
```
error[E0599]: the method `cmp` exists for reference `&T`, but its trait bounds were not satisfied
--> $DIR/method-on-unbounded-type-param.rs:5:10
|
LL | (&a).cmp(&b)
| ^^^ method cannot be called on `&T` due to unsatisfied trait bounds
|
= note: the following trait bounds were not satisfied:
`T: Ord`
which is required by `&T: Ord`
`&T: Iterator`
which is required by `&mut &T: Iterator`
`T: Iterator`
which is required by `&mut T: Iterator`
= help: items from traits can only be used if the type parameter is bounded by the trait
help: the following traits define an item `cmp`, perhaps you need to restrict type parameter `T` with one of them:
|
LL | fn g<T: Ord>(a: T, b: T) -> std::cmp::Ordering {
| +++++
LL | fn g<T: Iterator>(a: T, b: T) -> std::cmp::Ordering {
| ++++++++++
```
Fix#108428.
Follow up to #120396, only last commit is relevant.
```
error[E0277]: the size for values of type `[i32]` cannot be known at compilation time
--> f100.rs:2:33
|
2 | let _ = std::mem::size_of::<[i32]>();
| ^^^^^ doesn't have a size known at compile-time
|
= help: the trait `Sized` is not implemented for `[i32]`
note: required by an implicit `Sized` bound in `std::mem::size_of`
--> /home/gh-estebank/rust/library/core/src/mem/mod.rs:312:22
|
312 | pub const fn size_of<T>() -> usize {
| ^ required by the implicit `Sized` requirement on this bound in `size_of`
```
Fix#120178.
Expand the primary span of E0277 when the immediate unmet bound is not what the user wrote:
```
error[E0277]: the trait bound `i32: Bar` is not satisfied
--> f100.rs:6:6
|
6 | <i32 as Foo>::foo();
| ^^^ the trait `Bar` is not implemented for `i32`, which is required by `i32: Foo`
|
help: this trait has no implementations, consider adding one
--> f100.rs:2:1
|
2 | trait Bar {}
| ^^^^^^^^^
note: required for `i32` to implement `Foo`
--> f100.rs:3:14
|
3 | impl<T: Bar> Foo for T {}
| --- ^^^ ^
| |
| unsatisfied trait bound introduced here
```
Fix#40120.
When a method not found on a type parameter could have been provided by any
of multiple traits, suggest each trait individually, instead of a single
suggestion to restrict the type parameter with *all* of them.
Before:
```
error[E0599]: the method `cmp` exists for reference `&T`, but its trait bounds were not satisfied
--> $DIR/method-on-unbounded-type-param.rs:5:10
|
LL | (&a).cmp(&b)
| ^^^ method cannot be called on `&T` due to unsatisfied trait bounds
|
= note: the following trait bounds were not satisfied:
`T: Ord`
which is required by `&T: Ord`
`&T: Iterator`
which is required by `&mut &T: Iterator`
`T: Iterator`
which is required by `&mut T: Iterator`
help: consider restricting the type parameters to satisfy the trait bounds
|
LL | fn g<T>(a: T, b: T) -> std::cmp::Ordering where T: Iterator, T: Ord {
| +++++++++++++++++++++++++
```
After:
```
error[E0599]: the method `cmp` exists for reference `&T`, but its trait bounds were not satisfied
--> $DIR/method-on-unbounded-type-param.rs:5:10
|
LL | (&a).cmp(&b)
| ^^^ method cannot be called on `&T` due to unsatisfied trait bounds
|
= note: the following trait bounds were not satisfied:
`T: Ord`
which is required by `&T: Ord`
`&T: Iterator`
which is required by `&mut &T: Iterator`
`T: Iterator`
which is required by `&mut T: Iterator`
= help: items from traits can only be used if the type parameter is bounded by the trait
help: the following traits define an item `cmp`, perhaps you need to restrict type parameter `T` with one of them:
|
LL | fn g<T: Ord>(a: T, b: T) -> std::cmp::Ordering {
| +++++
LL | fn g<T: Iterator>(a: T, b: T) -> std::cmp::Ordering {
| ++++++++++
```
Fix#108428.
When encountering a type mismatch error involving `dyn Trait`, mention
the existence of boxed trait objects if the other type involved
implements `Trait`.
Partially addresses #102629.
Register even erroneous impls
Otherwise the specialization graph fails to pick it up, even though other code assumes that all impl blocks have an entry in the specialization graph.
also includes an unrelated cleanup of the specialization graph query
fixes #119827
On borrow return type, suggest borrowing from arg or owned return type
When we encounter a function with a return type that has an anonymous lifetime with no argument to borrow from, besides suggesting the `'static` lifetime we now also suggest changing the arguments to be borrows or changing the return type to be an owned type.
```
error[E0106]: missing lifetime specifier
--> $DIR/variadic-ffi-6.rs:7:6
|
LL | ) -> &usize {
| ^ expected named lifetime parameter
|
= help: this function's return type contains a borrowed value, but there is no value for it to be borrowed from
help: consider using the `'static` lifetime, but this is uncommon unless you're returning a borrowed value from a `const` or a `static`
|
LL | ) -> &'static usize {
| +++++++
help: instead, you are more likely to want to change one of the arguments to be borrowed...
|
LL | x: &usize,
| +
help: ...or alternatively, to want to return an owned value
|
LL - ) -> &usize {
LL + ) -> usize {
|
```
Fix#85843.
When encountering a fn call that has a path to another fn being passed
in, where an `Fn` impl is expected, and the arguments differ, suggest
wrapping the argument with a closure with the appropriate arguments.
When we encounter a function with a return type that has an anonymous
lifetime with no argument to borrow from, besides suggesting the
`'static` lifetime we now also suggest changing the arguments to be
borrows or changing the return type to be an owned type.
```
error[E0106]: missing lifetime specifier
--> $DIR/variadic-ffi-6.rs:7:6
|
LL | ) -> &usize {
| ^ expected named lifetime parameter
|
= help: this function's return type contains a borrowed value, but there is no value for it to be borrowed from
help: consider using the `'static` lifetime, but this is uncommon unless you're returning a borrowed value from a `const` or a `static`
|
LL | ) -> &'static usize {
| +++++++
help: instead, you are more likely to want to change one of the arguments to be borrowed...
|
LL | x: &usize,
| +
help: ...or alternatively, to want to return an owned value
|
LL - ) -> &usize {
LL + ) -> usize {
|
```
Fix#85843.
Pretty print `Fn` traits in `rustc_on_unimplemented`
I don't think that users really ever should need to think about `Fn*` traits' tupled args for a simple trait error.
r? diagnostics
