Fix incorrect diagnostics for expected type in E0271 with an associated type
With code like the following code:
```rust
#[derive(Debug)]
struct Data {}
fn do_stuff<'a>(iterator: impl Iterator<Item = &'a Data>) {
for item in iterator {
println!("{:?}", item)
}
}
fn main() {
let v = vec![Data {}];
do_stuff(v.into_iter());
}
```
the diagnostic (in nightly & stable) wrongly complains about the expected type:
```
error[E0271]: type mismatch resolving `<std::vec::IntoIter<Data> as std::iter::Iterator>::Item == &Data`
--> src/main.rs:15:5
|
5 | fn do_stuff<'a>(iterator: impl Iterator<Item = &'a Data>) {
| -------- --------------- required by this bound in `do_stuff`
...
15 | do_stuff(v.into_iter());
| ^^^^^^^^ expected struct `Data`, found &Data
|
= note: expected type `Data`
found type `&Data`
```
This PR fixes this issue by flipping the expected/actual values where appropriate, so it looks like this:
```
error[E0271]: type mismatch resolving `<std::vec::IntoIter<Data> as std::iter::Iterator>::Item == &Data`
--> main.rs:15:5
|
5 | fn do_stuff<'a>(iterator: impl Iterator<Item = &'a Data>) {
| -------- --------------- required by this bound in `do_stuff`
...
15 | do_stuff(v.into_iter());
| ^^^^^^^^ expected &Data, found struct `Data`
|
= note: expected type `&Data`
found type `Data`
```
This improves the output of a lot of existing tests (check out `associated-types-binding-to-type-defined-in-supertrait`!).
The only change which I wasn't too sure about is in the test `associated-types-overridden-binding-2`, but I think it's an improvement and the underlying problem is with handling of `trait_alias`.
Fix#57226, fix#64760, fix#58092.
Fix libunwind build: Define __LITTLE_ENDIAN__ for LE targets
If `__LITTLE_ENDIAN__` is missing, libunwind assumes big endian
and reads unwinding instructions wrong on ARM EHABI.
Fix#65765
Technical background in referenced bug.
I didn't run any automated tests, just built a simple panicking program using the fixed toolchain and panicking started to work. Tried with `catch_unwind()` and that seems to work now too. libunwind's log seems ok now, I can paste it if needed.
update submodules to rust-lang
These are the repositories I've moved from rust-lang-nursery to
rust-lang, so we should update the submodules too.
I have not tested that this builds at all, so please make sure CI is green!
Make `promote_consts` emit the errors when required promotion fails
A very minimal version of #65942.
This will cause a generic "argument X is required to be a constant" message for `simd_shuffle` LLVM intrinsics instead of the [custom one](caa1f8d7b3/src/librustc_mir/transform/qualify_consts.rs (L1616)). It may be possible to remove this special-casing altogether after rust-lang/stdarch#825.
r? @eddyb
rustdoc: Resolve module-level doc references more locally
Module level docs should resolve intra-doc links as locally as
possible. As such, this commit alters the heuristic for finding
intra-doc links such that we attempt to resolve names mentioned
in *inner* documentation comments within the (sub-)module rather
that from the context of its parent.
I'm hoping that this fixes#55364 though right now I'm not sure it's the right fix.
r? @GuillaumeGomez
Don't hide ICEs from previous incremental compiles
I think this fixes#65401, the compiler does not fail to ICE after the first compilation, tested on the last snippet of [this comment](https://github.com/rust-lang/rust/issues/63154#issuecomment-541592381).
I am not very sure of the fix as I don't understand much of the structure of the compiler.
Add lint and tests for unnecessary parens around types
This is my first contribution to the Rust project, so I apologize if I'm not doing things the right way.
The PR fixes#64169. It adds a lint and tests for unnecessary parentheses around types. I've run `tidy` and `rustfmt` — I'm not totally sure it worked right, though — and I've tried to follow the instructions linked in the readme.
I tried to think through all the variants of `ast::TyKind` to find exceptions to this lint, and I could only find the one mentioned in the original issue, which concerns types with `dyn`. I'm not a Rust expert, thought, so I may well be missing something.
There's also a problem with getting this to build. The new lint catches several things in the, e.g., `core`. Because `x.py` seems to build with an equivalent of `-Werror`, what would have been warnings cause the build to break. I got it to build and the tests to pass with `--warnings warn` on my `x.py build` and `x.py test` commands.
This is equivalent to the previous code in terms of performance. The
expensive path is clearly identical. The fast path is also the same,
because in both cases we loop until we get a non-empty `refined_ctors`,
and then stop there. So the new code doesn't compute anything more
than the previous did.
(Many thanks to alex for 1. making this even smaller than what I had
originally minimized, and 2. pointing out that there is precedent for
having ui tests with crate dependency chains of length > 2, thus
allowing me to avoid encoding this as a run-make test.)
rustc_codegen_ssa: introduce MIR VarDebugInfo, but only for codegen.
These are all the codegen changes necessary for #56231.
The refactors were performed locally to codegen, and in several steps, to ease reviewing and avoid introducing changes in behavior (as I'm not sure our debuginfo tests cover enough).
r? @michaelwoerister cc @nagisa @rkruppe @oli-obk
Dual proc macro hash
This PR changes current `-Z dual-proc-macro` mechanism from resolving only by name to including the hash of the host crate inside the transistive dependency information to prevent name conflicts.
Fix partially #62558
Fix `-Zunpretty=mir-cfg` to render multiple items
`-Zunpretty=mir-cfg` outputs DOT to stdout for all items being compiled. However, it puts all of these items in separate `digraph`s, which means the result of redirecting that output to a file is not valid. Most dot renderers (I have tried `dot` and `xdot`) cannot render the output.
This PR checks to see if `write_mir_graphviz` will process multiple items, and writes them each as a `subgraph` in a single, top-level `digraph`. As a result, DOT can be viewed without manually editing the output file. The output is unchanged when printing a single item (e.g.`-Zunpretty=mir-cfg=item_name`).
Here's the output of `xdot` for a rust file containing three items:
The borders are a result of the nonstandard–but well-supported–[`cluster` prefix](https://graphviz.gitlab.io/_pages/doc/info/lang.html) (search for "Subgraphs and Clusters"). They will not appear if your renderer does not support this extension, but the graph will still render properly.
