Fix a couple ICEs in the new `CastKind::Transmute` code
Check the sizes of the immediates, rather than the overall types, when deciding whether we can convert types without going through memory.
Fixes#110005Fixes#109992Fixes#110032
cc `@matthiaskrgr`
Reverts PR #108031
Fixes (doesnt close until beta backported) #109746
This reverts commit e3f9db5fc319c6d8eee5d47d216ea6a426070c41.
This reverts commit 98b82aedba3f3f581e89df54352914b27f42c6f7.
This reverts commit 380fa264132ad481e73cbbf0f3a0feefd99a1d78.
Migrate remainder of rustc_ty_utils to `SessionDiagnostic`
This moves the remaining errors in `rust_ty_utils` to `SessionsDiagnostic`.
r? ``@davidtwco``
Instantiate instead of erasing binder when probing param methods
Fixes#108836
There is a really old comment saying that a `WhereClauseCandidate` probe candidate "should not contain any inference variables", but I'm not really confident that that comment applies anymore. In contrast, other candidates that we assemble during method probe contain inference variables in their substitutions (e.g. `InherentImplCandidate`)...
Since this change is made only to support a nightly feature, I'm happy to gate the new behavior behind this feature flag or discuss it further.
r? types
Better diagnostic when pattern matching tuple structs
Fixes#108284
When trying to pattern match a tuple struct we might get a flawed error message if there are missing fields. E.g.
```
let x = Foo(100, 200);
if let Foo { 0: bar } = x { ... }
```
Produces this error:
```
error[E0769]: tuple variant `Foo` written as struct variant
--> hello.rs:5:12
|
5 | if let Foo { 0: foo } = x {
| ^^^^^^^^^^^^^^
|
help: use the tuple variant pattern syntax instead
|
5 | if let Foo(_, _) = x {
| ~~~~~~
```
Which doesn't highlight that we can still use the struct syntax but we need to fill missing fields. This pr changes this error to:
```
error[E0027]: pattern does not mention field `1`
--> hello.rs:5:12
|
5 | if let Foo { 0: foo } = x {
| ^^^^^^^^^^^^^^ missing field `1`
|
help: include the missing field in the pattern
|
5 | if let Foo { 0: foo, 1: _ } = x {
| ~~~~~~~~
help: if you don't care about this missing field, you can explicitly ignore it
|
5 | if let Foo { 0: foo, .. } = x {
| ~~~~~~
```
Suggest defining const parameter when appropriate
Helps a bit with #91119.
Following #105523's lead, I use placeholder `/* Type */` instead of `_` in the suggestion.
It should be easier for newcomers to parse.
`@rustbot` label A-diagnostics
r? diagnostics
Enforce that `PointerLike` requires a pointer-like ABI
At least temporarily, let's ban coercing things that are pointer-sized and pointer-aligned but *not* `Abi::Scalar(..)` into `dyn*`. See: https://github.com/rust-lang/rust/pull/104694#discussion_r1142522073
This can be lifted in the future if we decie that we *want* to be able to coerce something `repr(C)` into a `dyn*`, but we'll have to figure out what to do with Miri and codegen...
r? compiler
Add ability to transmute (somewhat) with generic consts in arrays
Previously if the expression contained generic consts and did not have a directly equivalent type, transmuting the type in this way was forbidden, despite the two sizes being identical. Instead, we should be able to lazily tell if the two consts are identical, and if so allow them to be transmuted.
This is done by normalizing the forms of expressions into sorted order of multiplied terms, which is not generic over all expressions, but should handle most cases.
This allows for some _basic_ transmutations between types that are equivalent in size without requiring additional stack space at runtime.
I only see one other location at which `SizeSkeleton` is being used, and it checks for equality so this shouldn't affect anywhere else that I can tell.
See [this Stackoverflow post](https://stackoverflow.com/questions/73085012/transmute-nested-const-generic-array-rust) for what was previously necessary to convert between types. This PR makes converting nested `T -> [T; 1]` transmutes possible, and `[uB*2; N] -> [uB; N * 2]` possible as well.
I'm not sure whether this is something that would be wanted, and if it is it definitely should not be insta-stable, so I'd add a feature gate.
More descriptive error when qself path doesnt have a trait on the RHS of `as`
`<Ty as Enum>::Assoc` should report that `Enum` is a trait. Main question is whether to eagerly report the error, or raise it with `return Err(..)` -- i'll note that in an inline comment though.
cc `@GuillaumeGomez` who said this came up at a Paris Rust meetup.
r? `@petrochenkov`
Inline try_from and try_into
To avoid link time dependency between core and compiler-builtins, when using opt-level that implicitly enables -Zshare-generics.
While compiler-builtins should be compiled with -Zshare-generics disabled, the -Zbuild-std does not ensure this at the moment.
r? `@bjorn3`
Refactor unwind in MIR
This makes unwinding from current `Option<BasicBlock>` into
```rust
enum UnwindAction {
Continue,
Cleanup(BasicBlock),
Unreachable,
Terminate,
}
```
cc `@JakobDegen` `@RalfJung` `@Amanieu`
migrate rustc_macros to syn 2.0
WIP at this point since I need to work on migrating the code that heavily uses `NestedMeta` for parsing. Perhaps a full refactor would be nice..
