Specifically, change `Ty` from this:
```
pub struct Predicate<'tcx> { inner: &'tcx PredicateInner<'tcx> }
```
to this:
```
pub struct Predicate<'tcx>(&'tcx Interned<PredicateS<'tcx>>)
```
where `PredicateInner` is renamed as `PredicateS`.
This (plus a few other minor changes) makes the parallels with `Ty` and
`TyS` much clearer, and makes the uniqueness more explicit.
Specifically, change `Ty` from this:
```
pub type Ty<'tcx> = &'tcx TyS<'tcx>;
```
to this
```
pub struct Ty<'tcx>(Interned<'tcx, TyS<'tcx>>);
```
There are two benefits to this.
- It's now a first class type, so we can define methods on it. This
means we can move a lot of methods away from `TyS`, leaving `TyS` as a
barely-used type, which is appropriate given that it's not meant to
be used directly.
- The uniqueness requirement is now explicit, via the `Interned` type.
E.g. the pointer-based `Eq` and `Hash` comes from `Interned`, rather
than via `TyS`, which wasn't obvious at all.
Much of this commit is boring churn. The interesting changes are in
these files:
- compiler/rustc_middle/src/arena.rs
- compiler/rustc_middle/src/mir/visit.rs
- compiler/rustc_middle/src/ty/context.rs
- compiler/rustc_middle/src/ty/mod.rs
Specifically:
- Most mentions of `TyS` are removed. It's very much a dumb struct now;
`Ty` has all the smarts.
- `TyS` now has `crate` visibility instead of `pub`.
- `TyS::make_for_test` is removed in favour of the static `BOOL_TY`,
which just works better with the new structure.
- The `Eq`/`Ord`/`Hash` impls are removed from `TyS`. `Interned`s impls
of `Eq`/`Hash` now suffice. `Ord` is now partly on `Interned`
(pointer-based, for the `Equal` case) and partly on `TyS`
(contents-based, for the other cases).
- There are many tedious sigil adjustments, i.e. adding or removing `*`
or `&`. They seem to be unavoidable.
In particular, there's now more protection against incorrect usage,
because you can only create one via `Interned::new_unchecked`, which
makes it more obvious that you must be careful.
There are also some tests.
Generator drop tracking: improve break and continue handling
This PR fixes two related issues.
One, sometimes break or continue have a block target instead of an expression target. This seems to mainly happen with try blocks. Since the drop tracking analysis only works on expressions, if we see a block target for break or continue, we substitute the last expression of the block as the target instead.
Two, break and continue were incorrectly being treated as the same, so continue would also show up as an exit from the loop or block. This patch corrects the way continue is handled by keeping a stack of loop entry points and uses those to find the target of the continue.
Fixes#93197
r? `@nikomatsakis`
make `find_similar_impl_candidates` even fuzzier
continues the good work of `@BGR360` in #92223. I might have overshot a bit and we're now slightly too fuzzy 😅
with this we can now also simplify `simplify_type`, which is nice :3
Make `Res::SelfTy` a struct variant and update docs
I found pattern matching on a `(Option<DefId>, Option<(DefId, bool)>)` to not be super readable, additionally the doc comments on the types in a tuple variant aren't visible anywhere at use sites as far as I can tell (using rust analyzer + vscode)
The docs incorrectly assumed that the `DefId` in `Option<(DefId, bool)>` would only ever be for an impl item and I also found the code examples to be somewhat unclear about which `DefId` was being talked about.
r? `@lcnr` since you reviewed the last PR changing these docs
Remove Config::stderr
1. It captured stdout and not stderr
2. It isn't used anywhere
3. All error messages should go to the DiagnosticOutput instead
4. It modifies thread local state
Marking as blocked as it will conflict a bit with https://github.com/rust-lang/rust/pull/93936.
1. It captured stdout and not stderr
2. It isn't used anywhere
3. All error messages should go to the DiagnosticOutput instead
4. It modifies thread local state
Couple of driver cleanups
* Remove the `RustcDefaultCalls` struct, which hasn't been necessary since the introduction of `rustc_interface`.
* Move the `setup_callbacks` call around for a tiny code deduplication.
* Remove the `SPAN_DEBUG` global as it isn't actually necessary.
Improve chalk integration
- Support subtype bounds in chalk lowering
- Handle universes in canonicalization
- Handle type parameters in chalk responses
- Use `chalk_ir::LifetimeData::Empty` for `ty::ReEmpty`
- Remove `ignore-compare-mode-chalk` for tests that no longer hang (they may still fail or ICE)
This is enough to get a hello world program to compile with `-Zchalk` now. Some of the remaining issues that are needed to get Chalk integration working on larger programs are:
- rust-lang/chalk#234
- rust-lang/chalk#548
- rust-lang/chalk#734
- Generators are handled differently in chalk and rustc
r? `@jackh726`
Apply noundef attribute to &T, &mut T, Box<T>, bool
This doesn't handle `char` because it's a bit awkward to distinguish it from `u32` at this point in codegen.
Note that this _does not_ change whether or not it is UB for `&`, `&mut`, or `Box` to point to undef. It only applies to the pointer itself, not the pointed-to memory.
Fixes (partially) #74378.
r? `@nikic` cc `@RalfJung`
Inherit lifetimes for async fn instead of duplicating them.
The current desugaring of `async fn foo<'a>(&usize) -> &u8` is equivalent to
```rust
fn foo<'a, '0>(&'0 usize) -> foo<'static, 'static>::Opaque<'a, '0, '_>;
type foo<'_a, '_0>::Opaque<'a, '0, '1> = impl Future<Output = &'1 u8>;
```
following the RPIT model.
Duplicating all the inherited lifetime parameters and setting the inherited version to `'static` makes lowering more complex and causes issues like #61949. This PR removes the duplication of inherited lifetimes to directly use
```rust
fn foo<'a, '0>(&'0 usize) -> foo<'a, '0>::Opaque<'_>;
type foo<'a, '0>::Opaque<'1> = impl Future<Output = &'1 u8>;
```
following the TAIT model.
Fixes https://github.com/rust-lang/rust/issues/61949
The only difference between the default and rustc_interface set version
is that the default accesses the source map from SESSION_GLOBALS while
the rustc_interface version accesses the source map from the global
TyCtxt. SESSION_GLOBALS is always set while running the compiler while
the global TyCtxt is not always set. If the global TyCtxt is set, it's
source map is identical to the one in SESSION_GLOBALS
This ensures that it is called even when run_in_thread_pool_with_globals
is avoided and reduces code duplication between the parallel and
non-parallel version of run_in_thread_pool_with_globals
tidy: Extend error code check
We discovered in https://github.com/rust-lang/rust/pull/93845 that the error code tidy check didn't check everything: if you remove an error code from the listing even if it has an explanation, then it should error.
It also allowed me to put back `E0192` in that listing as well.
r? ```@Mark-Simulacrum```
fix ICE when parsing lifetime as function argument
I don't really like this, but we basically need to emit an error instead of just delaying an bug, because there are too many places in the AST that aren't covered by my previous PRs...
cc: https://github.com/rust-lang/rust/issues/93282#issuecomment-1028052945
Implement `tainted_by_errors` in MIR borrowck, use it to skip CTFE
Putting this up for initial review. The issue that I found is when we're evaluating a const, we're doing borrowck, but doing nothing with the fact that borrowck fails.
This implements a `tainted_by_errors` field for MIR borrowck like we have in infcx, so we can use that information to return an `Err` during const eval if our const fails to borrowck.
This PR needs some cleaning up. I should probably just use `Result` in more places, instead of `.expect`ing in the places I am, but I just wanted it to compile so I could see if it worked!
Fixes#93646
r? `@oli-obk`
feel free to reassign
Use const generics in SipHasher128's short_write
This was proposed by `@michaelwoerister` [here](https://github.com/rust-lang/rust/pull/93615#discussion_r799485554).
A few comments:
1) I tried to pass `&[u8; LEN]` instead of `[u8; LEN]`. Locally, it resulted in small icount regressions (about 0.5 %). When passing by value, there were no regressions (and no improvements).
2) I wonder if we should use `to_ne_bytes()` in `SipHasher128` to keep it generic and only use `to_le_bytes()` in `StableHasher`. However, currently `SipHasher128` is only used in `StableHasher` and the `short_write` method was private, so I couldn't use it directly from `StableHasher`. Using `to_le()` in the `StableHasher` was breaking this abstraction boundary before slightly.
```rust
debug_assert!(LEN <= 8);
```
This could be done at compile time, but actually I think that now we can remove this assert altogether.
r? `@the8472`
