Avoid ICE when param-env normalization leaves unresolved inference variables
Fixesrust-lang/rust#153354
Because the impl is already ill-formed, those variables are not fully constrained, so zfully_resolve` fails. We previously treated that as an immediate compiler bug with `span_bug!`, which caused an ICE on invalid input.
Perform many const checks in typeck
Some smaller diagnostic changes, the biggest ones avoided by https://github.com/rust-lang/rust/pull/148641
We should be able to move various checks in mir const checking to using `span_bug!` instead of reporting an error, just like mir typeck does as a sanity check. I would like to start doing so separately though, as this PR is a big enough (in what effects it causes, pun intended).
r? @fee1-dead
The ICE fix appears to be unsound, causing a miscompilation involving
`dyn Trait` and `async {}` which induces segfaults in safe Rust code.
As the patch only hid an ICE, it does not seem worth the risk.
This reverts commit 8afd63610b, reversing
changes made to 19122c03c7.
Update mgca to use `type const` syntax instead of the `#[type_const]` attribute.
This PR changes the `#[type_const]` attribute to the `type const` syntax for https://github.com/rust-lang/rust/issues/132980.
This will fixes https://github.com/rust-lang/rust/issues/151273 and similar issues, since we need to check `type const` of items before expansion. The move to add a syntax was mentioned here: https://github.com/rust-lang/rust/pull/151289#issuecomment-3765241397
The first part of this PR adds support by allowing `type const <IDENT>: <TYPE> { = <EXPR> };` syntax in `rustc_parse/src/parser/item.rs`.
The next part since the AST item does not contain enough information to determine if we have a `type const` was rework `ConstItemRhs` into `ConstItemRhsKind` to store the information since we no longer have the attribute acting as a source of extra data/metadata.
The hir node `ConstItemRhsKind` current shape mostly works, except in the case of `TraitItemKind` where it is an option. I initially went about giving `hir::ConstItemRhsKind` a similar form the AST, but it touches a lot more lines of code and files so because of that, the less invasive option was to add a simple boolean flag to `TraitItemKind`.
The forth part of this PR includes adding a query I called `is_rhs_type_const` so that we can handle both local and foreign def_ids.
The fifth aspect of the PR is adding a `mgca_type_const_syntax` feature gate that is checked before expansion. The standard mgca feature gate is ran after expansion. This feature gate allows for conditional compilation (e.g #[cfg(..)]) of the `type const` syntax in nightly without `min_generic_const_args` being enabled.
The last bit is updating all the the tests that used the `#[type_const]` attribute to use the new syntax that failed because of the changes. This is the bulk of touched/edited files in the PR.
r? @BoxyUwU
@rustbot label +F-associated_const_equality +F-min_generic_const_args
Check stalled coroutine obligations eagerly
Fixesrust-lang/rust#151322Fixesrust-lang/rust#151323Fixesrust-lang/rust#137916Fixesrust-lang/rust#138274
The problem is that stalled coroutine obligations can't be satisifed so that they cause normalization to fail in `mir_borrowck`.
Thus, we failed to register any opaque to storage in the next solver.
I fix it by checking these obligations earlier in `mir_borrowck`.
r? @lcnr
Revert, but without type const.
Update symbol for feature err, then update suggestion output, and lastly update tests that change because of those.
Update these new tests with the correct syntax, and few existing tests with the new outputs the merge with main added.
Fix for tidyfmt and some errors when manually resolving a merge conflicts.
Update these tests to use update error messages and type const syntax.
Update comments and error message to use new syntax instead of old type_const attribute.
Remove the type_const attribute
update some more tests to use the new syntax.
Update these test cases.
update feature gate test
Change gate logic for `mgca_type_const_syntax` to work also if `min_generic_const_args` is enabled.
Create a new feature gate that checks for the feature before expansion.
Make rustfmt handle the `type const` syntax correctly.
Add a convience method to check if a RhsKind is type const.
Rename `Const` discriminant to `Body` for `ConstItemRhsKind`
Give the `TraitItemKind` flag an enum instead of a simple bool to better describe what the flag is for.
Update formatting for these match statements.
Update clippy test to use type const syntax.
Update test to use type const syntax.
update rustfmt to match ast items.
Update clippy to match ast and hir items.
Few more test cases that used old attribute, instead of 'type const'
Update to match the output from the feature gate checks.
tidyfmt adjustments.
Update the is_type_const, so I can constrain record!(..) in encoder.rs
Update conditional compilation test.
Move the feature gate to after expansion to allow for cfg(...) to work.
Update some more tests to use the new syntax.
Update type const tests in associated-const-bindings to use new syntax.
Don't check based off the attribute, but the item here.
Update some tests outside of the const_generics folder that were using #[type_const]
update the tests in associated consts that use #[type_const] to use type const
Update these mgca tests with the type const syntax.
Add a flag to TraitItemKind for detecting type const for now. Maybe later change ItemConstRhs to have optional consts but that touches a lot more lines of code.
Don't need into for these now that it's a query.
Add is_type_const query to handle foreign def ids.
update this test to use type const syntax.
Fix logic here, we only want to lower if there is expression in this case.
Update built-in macros to use ConstItemRhsKind
Update more instance of the old ConstItemRhs.
Rename ConstItemKind to ConstItemRhsKind, I noticed there is a typed called ConstantItemKind, so add the Rhs to the name to avoid confusion.
Update lower to use ConstItemKind
Add an other helper method to check if the rhs kinda has an expr.
Update item parse to use ConstItemKind enum.
Felt the field name could a be little clear when editing a few other things.
Change the ConstItem struct see know if we have a type const or regular const.
Make sure this syntax is properly feature gated.
mGCA: Make trait object types with type-level associated consts dyn compatible
Under feature `min_generic_const_args` (mGCA) (rust-lang/rust#132980), render traits with non-parametrized type-level associated constants (i.e., `#[type_const]` ones) dyn compatible but force the user to specify all type-level associated consts in the trait object type via bindings (either directly, via supertrait bounds and/or behind trait aliases) just like associated types, their sibling.
Fixesrust-lang/rust#130300 (feature request).
Fixesrust-lang/rust#136063 (bug).
Fixesrust-lang/rust#137260 (bug).
Fixesrust-lang/rust#137514 (bug).
While I'm accounting for most illegal `Self` references via const projections & params, I'm intentionally ignoring RUST-123140 (and duplicates) in this PR which is to be tackled some other time.
Additional context: Crate `rustc-demangle` had to be updated to fix v0 demangling. I've patched it in PR https://github.com/rust-lang/rustc-demangle/pull/87 which was was released in version 0.1.27 via PR https://github.com/rust-lang/rustc-demangle/pull/88.
Fixed ICE when using function pointer as const generic parameter
added bounds check in prohibit_explicit_late_bound_lifetimes to prevent index out of bounds panic when args.args is empty. also regression test here to ensure function pointers in const generics produce proper error messages instead of ICE.
Fixesrust-lang/rust#151186Fixesrust-lang/rust#137084
We used to lower such bad defaulted const args in trait object types to
`{type error}`; now correctly lower them to `{const error}`.
The added tests used to ICE prior to this change.
Normalize type_const items even with feature `generic_const_exprs`
Fixesrust-lang/rust#151251
With feature `generic_const_exprs` enabled, consts with `#[type_const]` won't be normalized even if they need. Then ICE happens when CTFE tries to evaluate such const without body.
Fix this by normalizing such consts even with feature `generic_const_exprs` enabled.
r? @BoxyUwU
Merge `associated_const_equality` feature gate into MGCA
Tracking Issues: rust-lang/rust#132980rust-lang/rust#92827
Merge `associated_const_equality`(ACE) feature gate into `min_generic_const_args`(MGCA).
- Replaces `features().associated_const_equality()` checks with `features().min_generic_const_args()`
- Updates the parser to gate associated const equality under `min_generic_const_args`
- Moves `associated_const_equality` to the removed features list
- Removes the `associated_const_equality` method from the `Features` trait
- Updates all affected tests and tools (rust-analyzer, clippy)
Closesrust-lang/rust#150617
r? `@BoxyUwU`
This removes `associated_const_equality` as a separate feature gate and makes it part of `min_generic_const_args` (mgca).
Key changes:
- Remove `associated_const_equality` from unstable features, add to removed
- Update all test files to use `min_generic_const_args` instead
- Preserve the original "associated const equality is incomplete" error message by specially handling `sym::associated_const_equality` spans in `feature_gate.rs`
- Rename FIXME(associated_const_equality) to FIXME(mgca)
MGCA: Support for tuple constructors
r? BoxyUwU
part of https://github.com/rust-lang/rust/issues/132980fixesrust-lang/rust#136379fixesrust-lang/rust#138132
i tried to keep implementation very minimal and it's very similar to how structs was implemented with small adjustments
this does not make const constructor like None works, just something like Some(n)
todo:
* ~~tests~~
* write a better description (not sure if needed)
* add more comments and FIXMEs from structs code
Instead of using a visitor in typeck, we just check, whenever lowering a
use of a param, whether the parent item is an MCG anon const during hir
ty lowering (and instantiate_value_path). If so, we report an error
since MCG anon consts should never be able to use generics. All other
kinds of anon consts are at least syntactically allowed to use generic
params.
We use a `TypeFolder` to accomplish this; this way, we look at the
fully explicit semantic representation of the type/const/whatever and
don't miss subtle cases like `Self` type aliases.
refactor `destructure_const`
r? BoxyUwU
as you suggested yesterday (will add more context like links when it stops being a draft)
tried to split this into some meaningful commits hope it help ^^
crash test readme: point to rustc-dev-guide
There is information that is duplicated here and in rustc-dev-guide, and the latter is more comprehensive, so point there.
The split between walk_pat and maybe_read_scrutinee has now become
redundant.
Due to this change, one testcase within the testsuite has become similar
enough to a known ICE to also break. I am leaving this as future work,
as it requires feature(type_alias_impl_trait)
Oli Scherer