Remove reachable coverage without counters
Remove reachable coverage without counters to maintain invariant that
either there is no coverage at all or there is a live coverage counter
left that provides the function source hash.
The motivating example would be a following closure:
```rust
let f = |x: bool| {
debug_assert!(x);
};
```
Which, with span changes from #93967, with disabled debug assertions,
after the final CFG simplifications but before removal of dead blocks,
gives rise to MIR:
```rust
fn main::{closure#0}(_1: &[closure@a.rs:2:13: 2:22], _2: bool) -> () {
debug x => _2;
let mut _0: ();
bb0: {
Coverage::Expression(4294967295) = 1 - 2;
return;
}
...
}
```
Which also makes the initial instrumentation quite suspect, although
this pull request doesn't attempt to address that aspect directly.
Fixes#98833.
r? ``@wesleywiser`` ``@richkadel``
Remove some explicit `self.infcx` for `FnCtxt`, which already derefs into `InferCtxt`
The use of `self.infcx.method_on_infcx` vs `self.method_on_infcx` when `self` is a `FnCtxt` is a bit inconsistent, so I'm moving some `self.infcx` usages I found to just use autoderef
Slightly improve mismatched GAT where clause error
This makes the error reporting a bit more standardized between `where` on GATs and functions.
cc #99206 (`@BoxyUwU),` don't want to mark this as as "fixed" because they're still not perfect, but this is still an improvement IMO so I want to land it incrementally.
regarding "consider adding where clause to trait definition", we don't actually do that for methods as far as i can tell? i could file an issue to look into that maybe.
Enable raw-dylib for bin crates
Fixes#93842
When `raw-dylib` is used in a `bin` crate, we need to collect all of the `raw-dylib` functions, generate the import library and add that to the linker command line.
I also changed the tests so that 1) the C++ dlls are created after the Rust dlls, thus there is no chance of accidentally using them in the Rust linking process and 2) disabled generating import libraries when building with MSVC.
Rollup of 9 pull requests
Successful merges:
- #92390 (Constify a few `(Partial)Ord` impls)
- #97077 (Simplify some code that depend on Deref)
- #98710 (correct the output of a `capacity` method example)
- #99084 (clarify how write_bytes can lead to UB due to invalid values)
- #99178 (Lighten up const_prop_lint, reusing const_prop)
- #99673 (don't ICE on invalid dyn calls)
- #99703 (Expose size_hint() for TokenStream's iterator)
- #99709 (`Inherited` always has `TypeckResults` available)
- #99713 (Fix sidebar background)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Expose size_hint() for TokenStream's iterator
The iterator for `proc_macro::TokenStream` is a wrapper around a `Vec` iterator:
babff2211e/library/proc_macro/src/lib.rs (L363-L371)
so it can cheaply provide a perfectly precise size hint, with just a pointer subtraction:
babff2211e/library/alloc/src/vec/into_iter.rs (L170-L177)
I need the size hint in syn (https://github.com/dtolnay/syn/blob/1.0.98/src/buffer.rs) to reduce allocations when converting TokenStream into syn's internal TokenBuffer representation.
Aside from `size_hint`, the other non-default methods in `std::vec::IntoIter`'s `Iterator` impl are `advance_by`, `count`, and `__iterator_get_unchecked`. I've included `count` in this PR since it is trivial. I did not include `__iterator_get_unchecked` because it is spoopy and I did not feel like dealing with that. Lastly, I did not include `advance_by` because that requires `feature(iter_advance_by)` (https://github.com/rust-lang/rust/issues/77404) and I noticed this comment at the top of libproc_macro:
babff2211e/library/proc_macro/src/lib.rs (L20-L22)
correct the output of a `capacity` method example
The output of this example in std::alloc is different from which shown in the comment. I have tested it on both Linux and Windows.
Simplify some code that depend on Deref
Now that we can assume #97025 works, it's safe to expect Deref is always in the first place of projections. With this, I was able to simplify some code that depended on Deref's place in projections. When we are able to move Derefer before `ElaborateDrops` successfully we will be able to optimize more places.
r? `@oli-obk`
Constify a few `(Partial)Ord` impls
Only a few `impl`s are constified for now, as #92257 has not landed in the bootstrap compiler yet and quite a few impls would need that fix.
This unblocks #92228, which unblocks marking iterator methods as `default_method_body_is_const`.
Resolve function lifetime elision on the AST
~Based on https://github.com/rust-lang/rust/pull/97720~
Lifetime elision for functions is purely syntactic in nature, so can be resolved on the AST.
This PR replicates the elision logic and diagnostics on the AST, and replaces HIR-based resolution by a `delay_span_bug`.
This refactor allows for more consistent diagnostics, which don't have to guess the original code from HIR.
r? `@petrochenkov`
