Support const args in type dependent paths (Take 2)
once more, except it is sound this time 🥰 previously #71154
-----
```rust
#![feature(const_generics)]
struct A;
impl A {
fn foo<const N: usize>(&self) -> usize { N }
}
struct B;
impl B {
fn foo<const N: usize>(&self) -> usize { 42 }
}
fn main() {
let a = A;
a.foo::<7>();
}
```
When calling `type_of` for generic const arguments, we now use the `TypeckTables` of the surrounding body to get the expected type.
This alone causes cycle errors though, as we now have `typeck_tables_of(main)` -> `...` ->
`type_of(main_ANON0 := 7)` -> `typeck_tables_of(main)` ⚡ (see https://github.com/rust-lang/rust/issues/68400#issuecomment-611760290)
To prevent this we must not call `type_of(const_arg)` during `typeck_tables_of`. This is achieved by
calling `type_of(param_def_id)` instead.
We have to somehow remember the `DefId` of the param through all of typeck, which is done using the
struct `ty::WithOptConstParam<DefId>`, which replaces `DefId` where needed and contains an `Option<DefId>` to
be able to store the const parameter in case it exists.
Queries which are currently cached on disk are split into two variants: `query_name`(cached) and `query_name_(of|for)_const_arg`(not cached), with `query_name_of_const_arg` taking a pair `(did, param_did): (LocalDefId, DefId)`.
For some queries a method `query_name_of_opt_const_arg` is added to `TyCtxt` which takes a `ty::WithOptConstParam` and either calls `query_name` or `query_name_of_const_arg` depending on the value of `const_param_did`.
r? @eddyb @varkor
Change `SymbolName::name` to a `&str`.
This eliminates a bunch of `Symbol::intern()` and `Symbol::as_str()`
calls, which is good, because they require locking the interner.
Note that the unsafety in `from_cycle_error()` is identical to the
unsafety on other adjacent impls.
r? @eddyb
This now reuses `fn discriminant_ty` in project, removing
some code duplication. Doing so made me realize that
we previously had a disagreement about the discriminant
type of generators, with MIR using `u32` and codegen and
trait selection using `i32`.
We now always use `u32`.
build dist for x86_64-unknown-illumos
This change creates a new Docker image, "dist-x86_64-illumos", and sets
things up to build the full set of "dist" packages for illumos hosts, so
that illumos users can use "rustup" to install packages. It also
adjusts the manifest builder to expect complete toolchains for this
platform.
This eliminates a bunch of `Symbol::intern()` and `Symbol::as_str()`
calls, which is good, because they require locking the interner.
Note that the unsafety in `from_cycle_error()` is identical to the
unsafety on other adjacent impls.
When encountering a local binding with a type that isn't completed, the
parser will reach a `=` token. When this happen, consider the type
"complete" as far as the parser is concerned to avoid further errors
being emitted by parse recovery logic.
Note that the output of `unpretty-debug.stdout` has changed. In that
test the hash values are normalized from a symbol numbers to small
numbers like "0#0" and "0#1". The increase in the number of static
symbols must have caused the original numbers to contain more digits,
resulting in different pretty-printing prior to normalization.
lint: use `transparent_newtype_field` to avoid ICE
Fixes#73747.
This PR re-uses the `transparent_newtype_field` function instead of manually calling `is_zst` on normalized fields to determine which field in a transparent type is the non-zero-sized field, thus avoiding an ICE.
typeck: use `item_name` in cross-crate packed diag
Fixes#73112.
This PR replaces the use of `expect_local` and `hir().get` to fetch the identifier for a ADT with `item_name` - which works across crates.