Associated types with a default type in a trait can't be relied upon to
remain of that default type when in use, so literals of that type can't
be used in the trait's items. Point at the associated type and state
that information.
Reduce verbosity for associated consts of the wrong type.
When an associated type is found when a specific type was expected, if
possible provide a structured suggestion constraining the associated
type in a bound.
```
error[E0271]: type mismatch resolving `<T as Foo>::Y == i32`
--> $DIR/associated-types-multiple-types-one-trait.rs:13:5
|
LL | want_y(t);
| ^^^^^^ expected `i32`, found associated type
...
LL | fn want_y<T:Foo<Y=i32>>(t: &T) { }
| ----- required by this bound in `want_y`
|
= note: expected type `i32`
found associated type `<T as Foo>::Y`
help: consider constraining the associated type `<T as Foo>::Y` to `i32`
|
LL | fn have_x_want_y<T:Foo<X=u32, Y = i32>>(t: &T)
| ^^^^^^^^^
```
```
error[E0308]: mismatched types
--> $DIR/trait-with-missing-associated-type-restriction.rs:12:9
|
LL | qux(x.func())
| ^^^^^^^^ expected `usize`, found associated type
|
= note: expected type `usize`
found associated type `<impl Trait as Trait>::A`
help: consider constraining the associated type `<impl Trait as Trait>::A` to `usize`
|
LL | fn foo(x: impl Trait<A = usize>) {
| ^^^^^^^^^^
```
Rollup of 6 pull requests
Successful merges:
- #71712 (Miri: port error backtraces to std::backtrace)
- #71736 (bootstrap: also apply unused-attributes hack without deny_warnings)
- #71738 (remove AllocId generalization of Pointer)
- #71739 (remove obsolete comment)
- #71781 (Uncomment test code for failure to use `Box::pin`)
- #71782 (Use a non-existent test path instead of clobbering /dev/null)
Failed merges:
r? @ghost
bootstrap: also apply unused-attributes hack without deny_warnings
This is a follow-up to https://github.com/rust-lang/rust/pull/70881 that also silences these warnings when deny_warnings is off. They otherwise spam my screen during development and make it hard to see actual warnings.
Cc @eddyb r? @Mark-Simulacrum
Miri: port error backtraces to std::backtrace
No need to pull in an external dependency if libstd already includes this feature (using the same dependency internally, but... still).
r? @oli-obk
wf: handle "livelock" checking before reaching `WfPredicates::compute`.
For `wf::obligations`'s "livelock" handling, this PR shouldn't cause any behavioral changes, as the check moved to it should be equivalent to the old one in `WfPredicates::compute`.
However, it fixes#70168 by making *other* users of `WfPredicates::compute` (that is, `wf::predicate_obligations` and `compute`'s own upvar handling) correct for `ty::Infer`, in that they now get a `WellFormed(ty::Infer(_))` obligation instead of silently ignoring the type.
r? @nikomatsakis
Rename `bitcode-in-rlib` option to `embed-bitcode`
This commit finishes work first pioneered in #70458 and started in #71528.
The `-C bitcode-in-rlib` option, which has not yet reached stable, is
renamed to `-C embed-bitcode` since that more accurately reflects what
it does now anyway. Various tests and such are updated along the way as
well.
This'll also need to be backported to the beta channel to ensure we
don't accidentally stabilize `-Cbitcode-in-rlib` as well.
Rollup of 5 pull requests
Successful merges:
- #71018 (handle ConstValue::ByRef in relate)
- #71758 (Remove leftover chalk types)
- #71760 (Document unsafety for `*const T` and `*mut T`)
- #71761 (doc: reference does not exist, probably a typo)
- #71762 (doc: this resulted in a link pointing to a non-existent target)
Failed merges:
- #71726 (Suggest deref when coercing `ty::Ref` to `ty::RawPtr` with arbitrary mutability)
r? @ghost
Remove leftover chalk types
Split out from #69406
Since the other PR is having memory problems with `parallel-compiler = true`, figured I should split this out. Surprisingly, this actually changes some errors, and I'm not quite sure why.
r? @nikomatsakis
Avoid duplicating code for each query
There are at the moment roughly 170 queries in librustc.
The way `ty::query` is structured, a lot of code is duplicated for each query.
I suspect this to be responsible for a part of librustc'c compile time.
The first part of this PR reduces the amount of code generic on the query,
replacing it by code generic on the key-value types. I can split it out if needed.
In a second part, the non-inlined methods in the `QueryAccessors` and `QueryDescription` traits
are made into a virtual dispatch table. This allows to reduce even more the number of generated
functions.
This allows to save 1.5s on check build, and 10% on the size of the librustc.rlib.
(Attributed roughly half and half).
My computer is not good enough to measure properly compiling time.
I have no idea of the effect on performance. A perf run may be required.
cc #65031
This commit finishes work first pioneered in #70458 and started in #71528.
The `-C bitcode-in-rlib` option, which has not yet reached stable, is
renamed to `-C embed-bitcode` since that more accurately reflects what
it does now anyway. Various tests and such are updated along the way as
well.
This'll also need to be backported to the beta channel to ensure we
don't accidentally stabilize `-Cbitcode-in-rlib` as well.
