Make ptr::slice_from_raw_parts a const fn available under a feature flag
A first step in the direction of https://github.com/rust-lang/rust/issues/67456 .
This makes `ptr::slice_from_raw_parts` and `ptr::slice_from_raw_parts_mut` available as a const fn under a feature flag.
Enable opting out of specific default LLVM arguments.
`rustc` by default adds a few arguments to LLVM (like `-mergefunc-use-aliases` for example). With this PR `rustc` will only emit these arguments if the same argument has not already been specified by the user via `-Cllvm-args`. This enables opting out of these defaults.
The PR also removes a PGO specific `-Z` flag the effect of which can also be easily achieved by `-Cllvm-args`.
Fixes https://github.com/rust-lang/rust/issues/64310.
Fix too restrictive checks on Drop impls
Fixes#34426. Fixes#58311.
This PR completes and extends #59497 (which has been inactive for a while now).
The problem generating both issues was that when checking that the `Predicate`s of the `Drop` impl are exactly the same as the ones of the struct definition, the check was essentially performed by a simple `==` operator, which was not handling correctly HRTBs and involved `Fn` types.
The implemented solution relies on the `relate` machinery to more correctly equate `Predicate`s, and on `anonymize_late_bound_regions` to handle HRTB in a more general way. As the `Relate` trait currently is implemented only for `TraitPredicate` and `ProjectionPredicate` (and as they were the ones generating problems), `relate` is used only for them while for other `Predicate`s the equality check is kept. I'm currently considering whether it would make sense to implement the `Relate` trait also for all other `Predicate`s to render the proposed solution more general.
refactor expr & stmt parsing + improve recovery
Summary of important changes (best read commit-by-commit, ignoring whitespace changes):
- `AttrVec` is introduces as an alias for `ThinVec<Attribute>`
- `parse_expr_bottom` and `parse_stmt` are thoroughly refactored.
- Extract diagnostics logic for `vec![...]` in a pattern context.
- Recovery is added for `do catch { ... }`
- Recovery is added for `'label: non_block_expr`
- Recovery is added for `var $local`, `auto $local`, and `mut $local`. Fixes#65257.
- Recovery is added for `e1 and e2` and `e1 or e2`.
- ~~`macro_legacy_warnings` is turned into an error (has been a warning for 3 years!)~~
- Fixes#63396 by forward-porting #64105 which now works thanks to added recovery.
- `ui-fulldeps/ast_stmt_expr_attr.rs` is turned into UI and pretty tests.
- Recovery is fixed for `#[attr] if expr {}`
r? @estebank
Rollup of 6 pull requests
Successful merges:
- #67130 (Const prop should finish propagation into user defined variables)
- #67163 (Split up ptr/mod.rs in libcore...)
- #67314 (Don't suppress move errors for union fields)
- #67392 (Fix unresolved type span inside async object)
- #67404 (Separate region inference logic from error handling better)
- #67428 (`is_binding_pat`: use explicit match & include or-pats in grammar)
Failed merges:
r? @ghost
Split up ptr/mod.rs in libcore...
...one with implementation detail for const ptr and the other with mut ptr
I am not sure if the "stable since 1.0.0" flags are the correct choice for the two additional mods.
Also, is it necessary for them to be "pub"? If so, there should be a good description for them.
Closes#66891
