Add hint for unresolved associated trait items if the trait has a single item
This PR introduces a special-cased hint for unresolved trait items paths. It is shown if:
- the path was not resolved to any existing trait item
- and no existing trait item's name was reasonably close with regard to edit distance
- and the trait only has a single item in the corresponding namespace
I didn't know where I should put tests, therefore so far I just managed to bless two existing tests. I would be glad for hints where should tests for a hint like this be created, how should they be named (with reference to the original issue?) and what tests should I create (is it enough to test it just for types? or create separate tests also for functions and constants?).
It could also be turned into a machine applicable suggestion I suppose.
This is my first `rustc` PR, so please go easy on me :)
Fixes: https://github.com/rust-lang/rust/issues/87638
Fix overflow in rustc happening if the `err_count()` is reduced in a stage.
This can happen if stashed diagnostics are removed or replaced with fewer errors. The semantics stay the same if built without overflow checks. Fixes#84219.
Background: I came across this independently by running `RUSTFLAGS="-C overflow-checks=on" ./x.py test`. Fixing this will allow us to move on and find further overflow errors with testing or fuzzing.
Rollup of 9 pull requests
Successful merges:
- #87561 (thread set_name haiku implementation.)
- #87715 (Add long error explanation for E0625)
- #87727 (explicit_generic_args_with_impl_trait: fix min expected number of generics)
- #87742 (Validate FFI-safety warnings on naked functions)
- #87756 (Add back -Zno-profiler-runtime)
- #87759 (Re-use std::sealed::Sealed in os/linux/process.)
- #87760 (Promote `aarch64-apple-ios-sim` to Tier 2)
- #87770 (permit drop impls with generic constants in where clauses)
- #87780 (alloc: Use intra doc links for the reserve function)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
alloc: Use intra doc links for the reserve function
The sentence exists to highlight the existence of a
performance footgun of repeated calls of the
reserve_exact function.
permit drop impls with generic constants in where clauses
Fixes#79248
`==` is not sufficient to check for equality between unevaluated consts which causes the above issue because the const in `[(); N - 1]:` on the impl and the const in `[(); N - 1]:` on the struct def are not seen as equal. Any predicate that can contain an unevaluated const cant use `==` here as it will cause us to incorrectly emit an error.
I dont know much about chalk but it seems like we ought to be relating the `TypeWellFormedFromEnv` instead of `==` as it contains a `Ty` so I added that too...
r? ``````@lcnr``````
Promote `aarch64-apple-ios-sim` to Tier 2
As per https://github.com/rust-lang/compiler-team/issues/428 this target becomes Tier 2.
---
I tested that the latest nightly has the target and I'm already building my project with that on CI and locally.
Re-use std::sealed::Sealed in os/linux/process.
This uses `std::sealed::Sealed` in `std::os::linux::process` instead of defining new `Sealed` traits there.
Add back -Zno-profiler-runtime
This was removed by #85284 in favor of `-Zprofiler-runtime=<name>`.However the suggested `-Zprofiler-runtime=None` doesn't work because`None` is treated as a crate name.
Validate FFI-safety warnings on naked functions
Test that FFI-safety warnings don't get accidentally dropped on naked
functions. The big picture is that if you implement a naked function
with the Rust ABI you'll get a warning. Further, if you implement a
naked function with a standardized ABI, but use non-FFI-safe types you
will still get a warning.
rust-lang/rfcs#2774rust-lang/rfcs#2972
cc ``````@joshtriplett`````` ``````@Amanieu`````` ``````@haraldh``````
explicit_generic_args_with_impl_trait: fix min expected number of generics
Fixes#87718
The problem was that `synth_type_param_count` was already subtracted from `named_type_param_count`, so this ended up being subtracted again. This caused `expected_min` to overflow, and ultimately resulting in weird and wrong behaviour.
I've also added another test not present in the original issue but caused by the same bug.
Generate links to definition in rustdoc source code pages
## Description
This PR adds an option (disabled by default) to add links in the source code page on ident. So for for example:
```rust
mod other_module;
struct Foo;
fn bar() {}
fn x<T: other_module::Trait>(f: Foo, g: other_module::Whatever, t: &T) {
let f: Foo = Foo;
bar();
f.some_method();
}
```
In the example (mostly in the `x` function), `other_module::Trait`, `Foo`, `other_module::Whatever`, `bar` and `some_method` are now links (and `other_module` at the top too).
In case there is a type coming from another crate, it'll link to its documentation page and not its definition (but you can then click on `[src]` so I guess it's fine).
Another important detail: I voluntarily didn't add links for primitive types. I think we can discuss about adding links on them or not in a later PR (adding the support for them would require only a few lines).
Here is a video summing up everything I wrote above:
https://user-images.githubusercontent.com/3050060/114622354-21307b00-9cae-11eb-834d-f6d8178a37bd.mp4
## Performance impact
So, on my computer, the performance remains more or less the same (which is quite surprising but that's a nice surprise). Here are the numbers:
Without the option:
* core: 1m 21s
* alloc: 26.78s
* std: 27.30s
* proc_macro: 4.50s
With source to definition links generation (I enabled by default the option):
* core: 1m 25s
* alloc: 25.76s
* std: 27.07s
* proc_macro: 4.66s
So no real change here (again, I'm very surprised by this fact).
For the size of the generated source files (only taking into account the `src` folder here since it's the only one impacted) by running `du -shc .` (when I am in the source folder).
Without the option: 11.939 MB
With the option: 12.611 MB
So not a big change here either. In all those docs, I ran `grep -nR '<a class=' . | wc -l` and got 43917. So there are quite a lot of links added. :)
cc `@rust-lang/rustdoc`
r? `@jyn514`
Core features cleanup
This sorts and categorizes the `#![features]` in `core` and removes unused ones.
This is part of #87766
The following feature attributes were unnecessary and are removed:
```diff
// Library features:
-#![feature(bool_to_option)]
-#![feature(char_indices_offset)]
-#![feature(pin_deref_mut)]
-#![feature(str_split_as_str)]
-#![feature(str_split_inclusive_as_str)]
// Language features:
-#![feature(arbitrary_self_types)]
-#![feature(custom_inner_attributes)]
-#![feature(nll)]
```
Disable unused variable lint for naked functions
In most calling conventions, accessing function parameters may require
stack access. However, naked functions have no assembly prelude to set
up stack access. This is why naked functions may only contain a single
`asm!()` block. All parameter access is done inside the `asm!()` block,
so we cannot validate the liveness of the input parameters. Therefore,
we should disable the lint for naked functions.
rust-lang/rfcs#2774rust-lang/rfcs#2972
`@joshtriplett` `@Amanieu` `@haraldh`
