A global predicate is not guarnatenteed to outlive all regions.
If the predicate involves late-bound regions, then it may fail
to outlive other regions (e.g. `for<'b> &'b bool: 'static` does not
hold)
We now only produce `EvaluatedToOk` when a global predicate has no
late-bound regions - in that case, the ony region that can be present
in the type is 'static
Fix ICE when lowering `trait A where for<'a> Self: 'a`
Fixes#88586.
r? `@jackh726`
Jack, this fix is much smaller in scope than what I think you were proposing in the issue. Let me know if you had a vision for a larger refactor here.
cc `@JohnTitor`
Perform Sync check on static items in wf-check instead of during const checks
r? `@RalfJung`
This check is solely happening on the signature of the static item and not on its body, therefor it belongs into wf-checking instead of const checking.
Make `TypeFolder::fold_*` return `Result`
Implements rust-lang/compiler-team#432.
Initially this is just a rebase of `@LeSeulArtichaut's` work in #85469 (abandoned; see https://github.com/rust-lang/rust/pull/85485#issuecomment-908781112). At that time, it caused a regression in performance that required some further exploration... with this rebased PR bors can hopefully report some perf analysis from which we can investigate further (if the regression is indeed still present).
r? `@jackh726` cc `@nikomatsakis`
Only check for errors in predicate when skipping impl assembly
Prior to PR #91205, checking for errors in the overall obligation
would check checking the `ParamEnv`, due to an incorrect
`super_visit_with` impl. With this bug fixed, we will now
bail out of impl candidate assembly if the `ParamEnv` contains
any error types.
In practice, this appears to be overly conservative - when an error
occurs early in compilation, we end up giving up early for some
predicates that we could have successfully evaluated without overflow.
By only checking for errors in the predicate itself, we avoid causing
additional spurious 'type annotations needed' errors after a 'real'
error has already occurred.
With this PR, the diagnostic changes caused by PR #91205 are reverted.
Prior to PR #91205, checking for errors in the overall obligation
would check checking the `ParamEnv`, due to an incorrect
`super_visit_with` impl. With this bug fixed, we will now
bail out of impl candidate assembly if the `ParamEnv` contains
any error types.
In practice, this appears to be overly conservative - when an error
occurs early in compilation, we end up giving up early for some
predicates that we could have successfully evaluated without overflow.
By only checking for errors in the predicate itself, we avoid causing
additional spurious 'type annotations needed' errors after a 'real'
error has already occurred.
With this PR, the diagnostic changes caused by PR #91205 are reverted.
Account for incorrect `where T::Assoc = Ty` bound
Provide suggestoin to constrain trait bound for associated type.
Revert incorrect changes to `missing-bounds` test.
Address part of #20041.
Rollup of 4 pull requests
Successful merges:
- #91169 (Change cg_ssa's get_param to borrow the builder mutably)
- #91176 (If the thread does not get the lock in the short term, yield the CPU)
- #91212 (Fix ICE due to out-of-bounds statement index when reporting borrowck error)
- #91225 (Fix invalid scrollbar display on source code page)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Fix ICE due to out-of-bounds statement index when reporting borrowck error
Replace an `[index]` with a `.get` when `statement_index` points to a basic-block terminator (and is therefore out-of-bounds in the statements list).
Fixes#91206
Cc ``@camsteffen``
r? ``@oli-obk``
Change cg_ssa's get_param to borrow the builder mutably
This is a small change to make `get_param` more flexible for codegens that may need to modify things when retrieving function parameters.
This will currently only be used by [rustc_codegen_nvvm](https://github.com/Rust-GPU/Rust-CUDA) (my own project), but may be useful to more codegens in the future.
This is needed because cg_nvvm needs to remap certain types to libnvvm-friendly types, such as `i128` -> `<2 x i64>`. Because cg_ssa does not give mutable access to the builder, i resorted to using a mutex:
```rs
fn get_param(&self, index: usize) -> Self::Value {
let val = llvm::get_param(self.llfn(), index as c_uint);
trace!("Get param `{:?}`", val);
unsafe {
let llfnty = LLVMRustGetFunctionType(self.llfn());
let map = self.remapped_integer_args.borrow();
if let Some((_, key)) = map.get(llfnty) {
if let Some((_, new_ty)) = key.iter().find(|t| t.0 == index) {
trace!("Casting irregular param {:?} to {:?}", val, new_ty);
return transmute_llval(
*self.llbuilder.lock().unwrap(),
&self.cx,
val,
*new_ty,
);
}
}
val
}
}
```
However, i predict this is pretty bad for performance, considering how much builders are called during codegen, so i would greatly appreciate having a more flexible API for this.
Fix stack overflow in `usefulness.rs`
Fix#88747
Applied the suggestion from `@nbdd0121,` not sure if this has any drawbacks. The first call to `ensure_sufficient_stack` is not needed to fix the test case, but I added it to be safe.
Visit `param_env` field in Obligation's `TypeFoldable` impl
This oversight appears to have gone unnoticed for a long time
without causing issues, but it should still be fixed.
Diagnostic tweaks
* On type mismatch caused by assignment, point at the source of the expectation
* Hide redundant errors
* Suggest `while let` when `let` is missing in some cases
* Do not emit unnecessary E0308 after E0070
* Show fewer errors on `while let` missing `let`
* Hide redundant E0308 on `while let` missing `let`
* Point at binding definition when possible on invalid assignment
* do not point at closure twice
* do not suggest `if let` for literals in lhs
* account for parameter types
