Test wasm32-wasip1 in CI, not wasm32-unknown-unknown
This commit changes CI to no longer test the `wasm32-unknown-unknown` target and instead test the `wasm32-wasip1` target. There was some discussion of this in a [Zulip thread], and the motivations for this PR are:
* Runtime failures on `wasm32-unknown-unknown` print nothing, meaning all you get is "something failed". In contrast `wasm32-wasip1` can print to stdout/stderr.
* The unknown-unknown target is missing lots of pieces of libstd, and while `wasm32-wasip1` is also missing some pieces (e.g. threads) it's missing fewer pieces. This means that many more tests can be run.
Overall my hope is to improve the debuggability of wasm failures on CI and ideally be a bit less of a maintenance burden.
This commit specifically removes the testing of `wasm32-unknown-unknown` and replaces it with testing of `wasm32-wasip1`. Along the way there were a number of other archiectural changes made as well, including:
* A new `target.*.runtool` option can now be specified in `config.toml` which is passed as `--runtool` to `compiletest`. This is used to reimplement execution of WebAssembly in a less-wasm-specific fashion.
* The default value for `runtool` is an ambiently located WebAssembly runtime found on the system, if any. I've implemented logic for Wasmtime.
* Existing testing support for `wasm32-unknown-unknown` and Emscripten has been removed. I'm not aware of Emscripten testing being run any time recently and otherwise `wasm32-wasip1` is in theory the focus now.
* I've added a new `//@ needs-threads` directive for `compiletest` and classified a bunch of wasm-ignored tests as needing threads. In theory these tests can run on `wasm32-wasi-preview1-threads`, for example.
* I've tried to audit all existing tests that are either `ignore-emscripten` or `ignore-wasm*`. Many now run on `wasm32-wasip1` due to being able to emit error messages, for example. Many are updated with comments as to why they can't run as well.
* The `compiletest` output matching for `wasm32-wasip1` automatically uses "match a subset" mode implemented in `compiletest`. This is because WebAssembly runtimes often add extra information on failure, such as the `unreachable` instruction in `panic!`, which isn't able to be matched against the golden output from native platforms.
* I've ported most existing `run-make` tests that use custom Node.js wrapper scripts to the new run-make-based-in-Rust infrastructure. To do this I added `wasmparser` as a dependency of `run-make-support` for the various wasm tests to use that parse wasm files. The one test that executed WebAssembly now uses `wasmtime`-the-CLI to execute the test instead. I have not ported over an exception-handling test as Wasmtime doesn't implement this yet.
* I've updated the `test` crate to print out timing information for WASI targets as it can do that (gets a previously ignored test now passing).
* The `test-various` image now builds a WASI sysroot for the WASI target and additionally downloads a fixed release of Wasmtime, currently the latest one at 18.0.2, and uses that for testing.
[Zulip thread]: https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/Have.20wasm.20tests.20ever.20caused.20problems.20on.20CI.3F/near/424317944
* The WASI targets deal with the `main` symbol a bit differently than
native so some `codegen` and `assembly` tests have been ignored.
* All `ignore-emscripten` directives have been updated to
`ignore-wasm32` to be more clear that all wasm targets are ignored and
it's not just Emscripten.
* Most `ignore-wasm32-bare` directives are now gone.
* Some ignore directives for wasm were switched to `needs-unwind`
instead.
* Many `ignore-wasm32*` directives are removed as the tests work with
WASI as opposed to `wasm32-unknown-unknown`.
Implement async closure signature deduction
Self-explanatory from title.
Regarding the interaction between signature deduction, fulfillment, and the new trait solver: I'm not worried about implementing closure signature deduction here because:
1. async closures are unstable, and
2. I'm reasonably confident we'll need to support signature deduction in the new solver somehow (i.e. via proof trees, which seem very promising).
This is in contrast to #109338, which was closed because it generalizes signature deduction for a *stable* kind of expression (`async {}` blocks and `Future` traits), and which proliferated usage may pose a stabilization hazard for the new solver.
I'll be certain to make sure sure we revisit the closure signature deduction problem by the time that async closures are being stabilized (which isn't particularly soon) (edit: Put it into the async closure tracking issue). cc `````@lcnr`````
r? `````@oli-obk`````
Use root obligation on E0277 for some cases
When encountering trait bound errors that satisfy some heuristics that tell us that the relevant trait for the user comes from the root obligation and not the current obligation, we use the root predicate for the main message.
This allows to talk about "X doesn't implement Pattern<'_>" over the most specific case that just happened to fail, like "char doesn't implement Fn(&mut char)" in
`tests/ui/traits/suggest-dereferences/root-obligation.rs`
The heuristics are:
- the type of the leaf predicate is (roughly) the same as the type from the root predicate, as a proxy for "we care about the root"
- the leaf trait and the root trait are different, so as to avoid talking about `&mut T: Trait` and instead remain talking about `T: Trait` instead
- the root trait is not `Unsize`, as to avoid talking about it in `tests/ui/coercion/coerce-issue-49593-box-never.rs`.
```
error[E0277]: the trait bound `&char: Pattern<'_>` is not satisfied
--> $DIR/root-obligation.rs:6:38
|
LL | .filter(|c| "aeiou".contains(c))
| -------- ^ the trait `Fn<(char,)>` is not implemented for `&char`, which is required by `&char: Pattern<'_>`
| |
| required by a bound introduced by this call
|
= note: required for `&char` to implement `FnOnce<(char,)>`
= note: required for `&char` to implement `Pattern<'_>`
note: required by a bound in `core::str::<impl str>::contains`
--> $SRC_DIR/core/src/str/mod.rs:LL:COL
help: consider dereferencing here
|
LL | .filter(|c| "aeiou".contains(*c))
| +
```
Fix#79359, fix#119983, fix#118779, cc #118415 (the suggestion needs to change), cc #121398 (doesn't fix the underlying issue).
Adjust error `yield`/`await` lowering
Adjust the lowering of `yield`/`await` outside of their correct scopes so that we no longer make orpan HIR exprs.
Previously, `yield EXPR` would be lowered directly to `hir::TyKind::Error` (which I'll call `<error>`) which means that `EXPR` was not present in the HIR, but now we lower it to `{ EXPR; <error> }` so that `EXPR` is not orphaned.
Fixes#121096
When encountering trait bound errors that satisfy some heuristics that
tell us that the relevant trait for the user comes from the root
obligation and not the current obligation, we use the root predicate for
the main message.
This allows to talk about "X doesn't implement Pattern<'_>" over the
most specific case that just happened to fail, like "char doesn't
implement Fn(&mut char)" in
`tests/ui/traits/suggest-dereferences/root-obligation.rs`
The heuristics are:
- the type of the leaf predicate is (roughly) the same as the type
from the root predicate, as a proxy for "we care about the root"
- the leaf trait and the root trait are different, so as to avoid
talking about `&mut T: Trait` and instead remain talking about
`T: Trait` instead
- the root trait is not `Unsize`, as to avoid talking about it in
`tests/ui/coercion/coerce-issue-49593-box-never.rs`.
```
error[E0277]: the trait bound `&char: Pattern<'_>` is not satisfied
--> $DIR/root-obligation.rs:6:38
|
LL | .filter(|c| "aeiou".contains(c))
| -------- ^ the trait `Fn<(char,)>` is not implemented for `&char`, which is required by `&char: Pattern<'_>`
| |
| required by a bound introduced by this call
|
= note: required for `&char` to implement `FnOnce<(char,)>`
= note: required for `&char` to implement `Pattern<'_>`
note: required by a bound in `core::str::<impl str>::contains`
--> $SRC_DIR/core/src/str/mod.rs:LL:COL
help: consider dereferencing here
|
LL | .filter(|c| "aeiou".contains(*c))
| +
```
Fix#79359, fix#119983, fix#118779, cc #118415 (the suggestion needs
to change).
Support async trait bounds in macros
r? fmease
This is similar to your work on const trait bounds. This theoretically regresses `impl async $ident:ident` in macros, but I doubt this is occurring in practice.
When encountering a tail expression in the then arm of an `if` expression
without an `else` arm, account for `async fn` and `async` blocks to
suggest `return`ing the value and pointing at the return type of the
`async fn`.
We now also account for AFIT when looking for the return type to point at.
Fix#115405.
Encode `coroutine_for_closure` for foreign crates
Async closures (and "coroutine closures" in general) need to have their child coroutine encoded. This PR does that.
r? oli-obk
Harmonize `AsyncFn` implementations, make async closures conditionally impl `Fn*` traits
This PR implements several changes to the built-in and libcore-provided implementations of `Fn*` and `AsyncFn*` to address two problems:
1. async closures do not implement the `Fn*` family traits, leading to breakage: https://crater-reports.s3.amazonaws.com/pr-120361/index.html
2. *references* to async closures do not implement `AsyncFn*`, as a consequence of the existing blanket impls of the shape `AsyncFn for F where F: Fn, F::Output: Future`.
In order to fix (1.), we implement `Fn` traits appropriately for async closures. It turns out that async closures can:
* always implement `FnOnce`, meaning that they're drop-in compatible with `FnOnce`-bound combinators like `Option::map`.
* conditionally implement `Fn`/`FnMut` if they have no captures, which means that existing usages of async closures should *probably* work without breakage (crater checking this: https://github.com/rust-lang/rust/pull/120712#issuecomment-1930587805).
In order to fix (2.), we make all of the built-in callables implement `AsyncFn*` via built-in impls, and instead adjust the blanket impls for `AsyncFn*` provided by libcore to match the blanket impls for `Fn*`.
For a rigid projection, recursively look at the self type's item bounds to fix the `associated_type_bounds` feature
Given a deeply nested rigid projection like `<<<T as Trait1>::Assoc1 as Trait2>::Assoc2 as Trait3>::Assoc3`, this PR adjusts both trait solvers to look at the item bounds for all of `Assoc3`, `Assoc2`, and `Assoc1` in order to satisfy a goal. We do this because the item bounds for projections may contain relevant bounds for *other* nested projections when the `associated_type_bounds` (ATB) feature is enabled. For example:
```rust
#![feature(associated_type_bounds)]
trait Trait1 {
type Assoc1: Trait2<Assoc2: Foo>;
// Item bounds for `Assoc1` are:
// `<Self as Trait1>::Assoc1: Trait2`
// `<<Self as Trait1>::Assoc1 as Trait2>::Assoc2: Foo`
}
trait Trait2 {
type Assoc2;
}
trait Foo {}
fn hello<T: Trait1>(x: <<T as Trait1>::Assoc1 as Trait2>::Assoc2) {
fn is_foo(_: impl Foo) {}
is_foo(x);
// Currently fails with:
// ERROR the trait bound `<<Self as Trait1>::Assoc1 as Trait2>::Assoc2: Foo` is not satisfied
}
```
This has been a long-standing place of brokenness for ATBs, and is also part of the reason why ATBs currently desugar so differently in various positions (i.e. sometimes desugaring to param-env bounds, sometimes desugaring to RPITs, etc). For example, in RPIT and TAIT position, `impl Foo<Bar: Baz>` currently desugars to `impl Foo<Bar = impl Baz>` because we do not currently take advantage of these nested item bounds if we desugared them into a single set of item bounds on the opaque. This is obviously both strange and unnecessary if we just take advantage of these bounds as we should.
## Approach
This PR repeatedly peels off each projection of a given goal's self type and tries to match its item bounds against a goal, repeating with the self type of the projection. This is pretty straightforward to implement in the new solver, only requiring us to loop on the self type of a rigid projection to discover inner rigid projections, and we also need to introduce an extra probe so we can normalize them.
In the old solver, we can do essentially the same thing, however we rely on the fact that projections *should* be normalized already. This is obviously not always the case -- however, in the case that they are not fully normalized, such as a projection which has both infer vars and, we bail out with ambiguity if we hit an infer var for the self type.
## Caveats
⚠️ In the old solver, this has the side-effect of actually stalling some higher-ranked trait goals of the form `for<'a> <?0 as Tr<'a>>: Tr2`. Because we stall them, they no longer are eagerly treated as error -- this cause some existing `known-bug` tests to go from fail -> pass.
I'm pretty unconvinced that this is a problem since we make code that we expect to pass in the *new* solver also pass in the *old* solver, though this obviously doesn't solve the *full* problem.
## And then also...
We also adjust the desugaring of ATB to always desugar to a regular associated bound, rather than sometimes to an impl Trait **except** for when the ATB is present in a `dyn Trait`. We need to lower `dyn Trait<Assoc: Bar>` to `dyn Trait<Assoc = impl Bar>` because object types need all of their associated types specified.
I would also be in favor of splitting out the ATB feature and/or removing support for object types in order to stabilize just the set of positions for which the ATB feature is consistent (i.e. always elaborates to a bound).
Build DebugInfo for async closures
The test is pretty bare, because I don't really know how to write debuginfo tests. I'd like to land this first, and then flesh it out correctly one it's no longer ICEing on master (which breaks people's ability to test using async closures).
r? oli-obk cc `@rust-lang/wg-debugging` (if any of y'all want to help me write a more fleshed out async closures test)
Rollup of 9 pull requests
Successful merges:
- #119592 (resolve: Unload speculatively resolved crates before freezing cstore)
- #120103 (Make it so that async-fn-in-trait is compatible with a concrete future in implementation)
- #120206 (hir: Make sure all `HirId`s have corresponding HIR `Node`s)
- #120214 (match lowering: consistently lower bindings deepest-first)
- #120688 (GVN: also turn moves into copies with projections)
- #120702 (docs: also check the inline stmt during redundant link check)
- #120727 (exhaustiveness: Prefer "`0..MAX` not covered" to "`_` not covered")
- #120734 (Add `SubdiagnosticMessageOp` as a trait alias.)
- #120739 (improve pretty printing for associated items in trait objects)
r? `@ghost`
`@rustbot` modify labels: rollup
Make it so that async-fn-in-trait is compatible with a concrete future in implementation
There's no technical reason why an AFIT like `async fn foo()` cannot be satisfied with an implementation signature like `fn foo() -> Pin<Box<dyn Future<Output = ()> + 'static>>`.
We rejected this previously because we were uncertain about how AFITs worked with refinement, but I don't believe this needs to be a restriction any longer.
r? oli-obk
Stop bailing out from compilation just because there were incoherent traits
fixes#120343
but also has a lot of "type annotations needed" fallout. Some are fixed in the second commit.
Don't expect early-bound region to be local when reporting errors in RPITIT well-formedness
The implicit lifetime in the example code gets replaced with `ReError`, which fails a `sub_regions` check in the lexical region solver. Error reporting ends up calling `is_suitable_region` on an early bound region in the *trait* definition. This causes an ICE because we `expect_local()`.
This is kind of a bad explanation, but this code just makes diagnostics reporting a bit more gracefully fallible. If the reviewer wants a thorough investigation of exactly where we get this region outlives obligation, I can write one up. Doesn't really seem worth it, though, imo.
Fixes#120638Fixes#120648
