[perf] Compute hard errors without diagnostics in impl_intersection_has_impossible_obligation
First compute hard errors without diagnostics, then ambiguities with diagnostics since we need to know if any of them overflowed.
This commit adds a lint to prevent the use of rustc_type_ir in random
compiler crates, except for type system internals traits, which are
explicitly allowed. Moreover, this fixes diagnostic_items() to include
the CRATE_OWNER_ID, otherwise rustc_diagnostic_item attribute is ignored
on the crate root.
Make root vars more stable
Never resolve a ty/ct vid to a higher vid as its root. This should make the optimization in rust-lang/rust#141500 more "stable" when there are a lot of vars flying around.
r? `@ghost`
Treat normalizing consts like normalizing types in deeply normalize
...so that we don't end up putting a top-level normalizes-to goal in the fulfillment context, which ICEs. This basically just models the normalize-const code off of the normalize-ty code above it, which uses an alias-relate goal instead.
Fixesrust-lang/rust#140571
r? lcnr
add additional `TypeFlags` fast paths
Some crates, e.g. `diesel`, have items with a lot of where-clauses (more than 150). In these cases checking the `TypeFlags` of the whole `param_env` can be very beneficial.
This adds `fn fold_clauses` to mirror the existing `fn visit_clauses` and then uses this in folders which fold `ParamEnv`s.
Split out from rust-lang/rust#141451, depends on rust-lang/rust#141442.
r? `@compiler-errors`
Don't rerun goals if none of their vars have changed
r? `@ghost`
Alternative to rust-lang/rust#141488. I'm pretty sure that we don't need to re-run the goal at all if the inputs don't change... 🤔
detect additional uses of opaques after writeback
Based on #140607. It's a lot harder to encounter in practice than I though 😅😁 I've still added it with the expectation that somebody will encounter it at some point.
Also modifies the `EvalCtxt` to use the same impl to detect newly added opaque types.
r? ``@compiler-errors``
support duplicate entries in the opaque_type_storage
Necessary for the new solver as we may unify keys when eagerly resolving for canonical queries. See the relevant comment when instantiating query responses:
```rust
// We eagerly resolve inference variables when computing the query response.
// This can cause previously distinct opaque type keys to now be structurally equal.
//
// To handle this, we store any duplicate entries in a separate list to check them
// at the end of typeck/borrowck. We could alternatively eagerly equate the hidden
// types here. However, doing so is difficult as it may result in nested goals and
// any errors may make it harder to track the control flow for diagnostics.
if let Some(prev) = prev {
self.delegate.add_duplicate_opaque_type(key, prev, self.origin_span);
}
```
This will be far more relevant with #140497.
r? `@compiler-errors`
Removing rustc_type_ir in the rustc_infer codebase
cc #138449
This is a second refactoring of rustc_type_ir to use rustc_middle instead, this time that's for rustc_infer
This commit does the following:
- Replaces use of rustc_type_ir by rustc_middle in rustc_infer.
- The DelayedMap type is exposed by rustc_middle so everything can be
accessed through rustc_middle in a coherent manner.
- API-layer traits, like InferCtxtLike, Interner or inherent::* must be
accessed via rustc_type_ir, not rustc_middle::ty. For this reason
these are not reexported by rustc_middle::ty.
- Replaces use of ty::Interner by rustc_type_ir::Interner in
rustc_trait_selection
Remove `weak` alias terminology
I find the "weak" alias terminology to be quite confusing. It implies the existence of "strong" aliases (which do not exist) and I'm not really sure what about weak aliases is "weak". I much prefer "free alias" as the term. I think it's much more obvious what it means as "free function" is a well defined term that already exists in rust.
It's also a little confusing given "weak alias" is already a term in linker/codegen spaces which are part of the compiler too. Though I'm not particularly worried about that as it's usually very obvious if you're talking about the type system or not lol. I'm also currently trying to write documentation about aliases and it's somewhat awkward/confusing to be talking about *weak* aliases, when I'm not really sure what the basis for that as the term actually *is*.
I would also be happy to just find out there's a nice meaning behind calling them "weak" aliases :-)
r? `@oli-obk`
maybe we want a types MCP to decide on a specific naming here? or maybe we think its just too late to go back on this naming decision ^^'
