Disentangle `ForwardGenericParamBan` and `ConstParamTy` ribs
In #137617, the `ConstParamTy` rib was adjusted to act kinda like the `ForwardGenericParamBan`. However, this means that it no longer served its purpose banning generics from *parent items*. Although we still are checking for param type validity using the `ConstParamTy_` trait, which means that we weren't accepting code we shouldn't, I think it's a bit strange for us not to be rejecting code like this during *resolution* and instead letting these malformed const generics leak into the type system:
```rust
trait Foo<T> {
fn bar<const N: T>() {}
}
```
This PR does a few things:
1. Introduce a `ForwardGenericParamBanReason` enum, and start using the `ForwardGenericParamBan` rib to ban forward-declared params in const tys when `generic_const_parameter_types` is enabled.
2. Start using the `ConstParamTy` rib to ban *all* generics when `generic_const_parameter_types` is disabled.
3. Improve the diagnostics for both of the cases above, and for forward-declared params in parameter defaults too :3
r? `@BoxyUwU` or reassign
Support rmeta inputs for --crate-type=bin --emit=obj
This already works for --emit=metadata, but is possible anytime we're not linking.
Tests:
- `rmeta_bin` checks we're not changing --emit=link (already passes)
- `rmeta_bin-pass` tests the new behavior for --emit=obj (would fail today) and also --emit=metadata which isn't changing
change definitely unproductive cycles to error
builds on top of #136824 by adding a third variant to `PathKind` for paths which may change to be coinductive in the future but must not be so right now. Most notably, impl where-clauses of not yet coinductive traits.
With this, we can change cycles which are definitely unproductive to a proper error. This fixes https://github.com/rust-lang/trait-system-refactor-initiative/issues/114. This does not affect stable as we keep these cycles as ambiguous during coherence.
r? ````````@compiler-errors```````` ````````@nikomatsakis````````
Fix false-positive in `expr_or_init` and in the `invalid_from_utf8` lint
This PR fixes the logic for finding initializer in the `expr_or_init` and `expr_or_init_with_outside_body` functions.
If the binding were to be mutable (`let mut`), the logic wouldn't consider that the initializer expression could have been modified and would return the init expression even-trough multiple subsequent assignments could have been done.
Example:
```rust
let mut a = [99, 108, 130, 105, 112, 112]; // invalid, not UTF-8
loop {
a = *b"clippy"; // valid
break;
}
std::str::from_utf8_mut(&mut a); // currently warns, with this PR it doesn't
```
This PR modifies the logic to excludes mutable let bindings.
Found when using `expr_or_init` in https://github.com/rust-lang/rust/pull/119220.
r? compiler
Elaborate trait assumption in `receiver_is_dispatchable`
Fixes#138172. See comment on the linked test.
Probably not a fix for the general problem, bc I think this may still be incomplete for other weird `where` clauses on the receiver. But 🤷, supertraits seems like an obvious one to fix.
Rollup of 10 pull requests
Successful merges:
- #137715 (Allow int literals for pattern types with int base types)
- #138002 (Disable CFI for weakly linked syscalls)
- #138051 (Add support for downloading GCC from CI)
- #138231 (Prevent ICE in autodiff validation by emitting user-friendly errors)
- #138245 (stabilize `ci_rustc_if_unchanged_logic` test for local environments)
- #138256 (Do not feed anon const a type that references generics that it does not have)
- #138284 (Do not write user type annotation for const param value path)
- #138296 (Remove `AdtFlags::IS_ANONYMOUS` and `Copy`/`Clone` condition for anonymous ADT)
- #138352 (miri native_calls: ensure we actually expose *mutable* provenance to the memory FFI can access)
- #138354 (remove redundant `body` arguments)
r? `@ghost`
`@rustbot` modify labels: rollup
Do not write user type annotation for const param value path
As I noted in the code comment, `DefKind::ConstParam` isn't actually *generic* over its own args, we just use the identity args from the body when lowering the value path so we have something to plug into the `EarlyBinder` we get back from `type_of` for the const param. So skip over it in `write_user_type_annotation_from_args`.
Somewhat unrelated, but I left an explanation for a somewhat mysterious quirk in the THIR lowering of user type annotations for patterns having to do with ctors and their `type_of` not actually being the type of the pattern node it's ascribing.
Fixes#138048
r? ``@BoxyUwU``
Do not feed anon const a type that references generics that it does not have
Fixes#137865
See the comment I left in the code. We could alternatively give these anon consts the generics from the parent, but that would be moving in a GCE-esque direction that we may not want. Open to tweaks here.
r? BoxyUwU
Prevent ICE in autodiff validation by emitting user-friendly errors
This PR moves `valid_ret_activity` and `valid_input_activity` checks to the macro expansion phase in compiler/rustc_builtin_macros/src/autodiff.rs, replacing the following internal compiler error (ICE):
```
error: internal compiler error:
compiler/rustc_codegen_ssa/src/codegen_attrs.rs:935:13:
Invalid input activity Dual for Reverse mode
```
with a more user-friendly message.
The issue specifically affected the test file `tests/ui/autodiff/autodiff_illegal.rs`, impacting the functions `f5` and `f6`.
The ICE can be reproduced by following [Enzyme's Rustbook](https://enzymead.github.io/rustbook/installation.html) installation guide.
Additionally, this PR adds tests for invalid return activity in `autodiff_illegal.rs`, which previously triggered an unnoticed ICE before these fixes.
r? ``@oli-obk``
Allow int literals for pattern types with int base types
r? ``@BoxyUwU``
I also added an error at layout computation time for layouts that contain wrapping ranges (happens at monomorphization time). This is obviously hacky, but at least prevents such types from making it to codegen for now. It made writing the tests for int literals easier as I didn't have to think about that edge case
Basically this PR allows you to stop using transmutes for creating pattern types and instead just use literals:
```rust
let x: pattern_type!(u32 is 5..10) = 7;
```
works, and if the literal is out of range you get a type mismatch because it just stays at the base type and the base type can't be coerced to the pattern type.
cc ``@joshtriplett`` ``@scottmcm``
Add `#[define_opaques]` attribute and require it for all type-alias-impl-trait sites that register a hidden type
Instead of relying on the signature of items to decide whether they are constraining an opaque type, the opaque types that the item constrains must be explicitly listed.
A previous version of this PR used an actual attribute, but had to keep the resolved `DefId`s in a side table.
Now we just lower to fields in the AST that have no surface syntax, instead a builtin attribute macro fills in those fields where applicable.
Note that for convenience referencing opaque types in associated types from associated methods on the same impl will not require an attribute. If that causes problems `#[defines()]` can be used to overwrite the default of searching for opaques in the signature.
One wart of this design is that closures and static items do not have generics. So since I stored the opaques in the generics of functions, consts and methods, I would need to add a custom field to closures and statics to track this information. During a T-types discussion we decided to just not do this for now.
fixes#131298
When migrating the standard library to 2024, there will be some behavior
changes that users will be able to observe. This test should cover that
(I cannot think of any other observable differences).
Improve `-Zunpretty=hir` for parsed attrs
0. Rename `print_something` to `should_render` to make it distinct from `print_attribute` in that it doesn't print anything, it's just a way to probe if a type renders anything.
1. Fixes a few bugs in the `PrintAttribute` derive. Namely, the `__printed_anything` variable was entangled with the `should_render` call, leading us to always render field names but never render commas.
2. Remove the outermost `""` from the attr.
3. Debug print `Symbol`s. I know that this is redundant for some parsed attributes, but there's no good way to distinguish symbols that are ident-like and symbols which are cooked string literals. We could perhaps *conditionally* to fall back to a debug printing if the symbol doesn't match an ident? But seems like overkill.
Based on #138060, only review the commits not in that one.
[AIX] Fix hangs during testing
Fixes all current test hangs experienced during CI runs.
1. ipv6 link-local (the loopback device) gets assigned an automatic zone id of 1, causing the assert to fail and hang in `library/std/src/net/udp/tests.rs`
2. Const alloc does not fail gracefully
3. Debuginfo test has problem with gdb auto load safe path
Eliminate any redundant, unobservable logic from the their default
method implementations.
The observable changes are that `Write::write_fmt` for both types now
ignores the formatting arguments, so a user fmt impl which has side
effects is not invoked, and `Write::write_all_vectored` for both types
does not advance the borrowed buffers. Neither behavior is guaranteed by
the docs and the latter is documented as unspecified.
`Empty` is not marked as vectored, so that `Chain<Empty, _>` and
`Chain<_, Empty>` are not forced to be vectored.
Fix dyn -> param suggestion in struct ICEs
Makes the logic from #138042 a bit less ICEy and more clean. Also fixes an incorrect suggestion when the struct already has generics. I'll point out the major changes and observations in the code.
Fixes#138229Fixes#138211
r? nnethercote since you reviewed the original pr, or re-roll if you don't want to review this
Add a test for `-znostart-stop-gc` usage with LLD
This test replicates the behavior of https://github.com/dtolnay/linkme, to test that it still works even with LLD. Without `-znostart-stop-gc` the test fails.
r? ``@lqd``
try-job: x86_64-gnu
try-job: x86_64-msvc-1
