Commit graph

549 commits

Author SHA1 Message Date
Manish Goregaokar
2e53ac53e7
Rollup merge of #75007 - GuillaumeGomez:cleanup-e0743, r=pickfire
Clean up E0743 explanation

r? @Dylan-DPC
2020-08-01 09:30:19 -07:00
Manish Goregaokar
60bf83d215
Rollup merge of #74977 - GuillaumeGomez:cleanup-e0741, r=pickfire
Clean up E0741 error explanation

r? @Dylan-DPC
2020-08-01 09:30:11 -07:00
Guillaume Gomez
4bd313fb0f Clean up E0743 explanation 2020-08-01 15:19:00 +02:00
Guillaume Gomez
1a6730e31c Clean up E0741 error explanation 2020-07-31 13:15:47 +02:00
Manish Goregaokar
2c6c764d9a
Rollup merge of #74907 - GuillaumeGomez:cleanup-e0740, r=pickfire
Clean up E0740 explanation

r? @Dylan-DPC
2020-07-30 13:04:38 -07:00
Manish Goregaokar
172b3a713a
Rollup merge of #74835 - GuillaumeGomez:cleanup-e0734, r=jyn514
Clean up E0734 explanation

r? @Dylan-DPC
2020-07-30 13:04:32 -07:00
Manish Goregaokar
7e86c8eccb
Rollup merge of #74751 - GuillaumeGomez:cleanup-e0730, r=jyn514
Clean up E0730 explanation

r? @Dylan-DPC
2020-07-30 13:04:23 -07:00
Guillaume Gomez
89e4fe3313 Improve E0730 explanation 2020-07-30 13:51:22 +02:00
Guillaume Gomez
759de11f53 Clean up E0740 explanation 2020-07-29 14:06:29 +02:00
Yuki Okushi
1ed74eeef9
Rollup merge of #74266 - GuillaumeGomez:cleanup-e0720, r=Dylan-DPC
Clean up E0720 explanation

r? @Dylan-DPC
2020-07-29 09:24:13 +09:00
Guillaume Gomez
f22a34e84d Clean up E0734 explanation 2020-07-27 20:55:30 +02:00
bors
8cb94fc552 Auto merge of #74246 - GuillaumeGomez:cleanup-e0719, r=Dylan-DPC
Clean up E0719 explanation

r? @Dylan-DPC
2020-07-25 20:11:20 +00:00
Guillaume Gomez
1d2e3fff69 Clean up E0730 explanation 2020-07-25 18:57:42 +02:00
Yuki Okushi
2406c932d7
Rollup merge of #74694 - GuillaumeGomez:cleanup-e0727, r=Dylan-DPC
Clean up E0727 explanation

r? @Dylan-DPC
2020-07-24 18:56:42 +09:00
Yuki Okushi
a816345536
Rollup merge of #74601 - GuillaumeGomez:cleanup-e0724, r=jyn514
Clean up E0724 explanation

r? @Dylan-DPC
2020-07-24 18:56:29 +09:00
Yuki Okushi
0651dd4aab
Rollup merge of #74572 - Mark-Simulacrum:unify-rustc-depr, r=petrochenkov
Internally unify rustc_deprecated and deprecated

This PR intentionally tries to be "featureless" in that the behavior is not altered for either attribute, though it more clearly exposes cases where that is the case in the code.
2020-07-24 18:56:27 +09:00
Guillaume Gomez
d6b50d8230 Clean up E0724 explanation 2020-07-23 21:16:16 +02:00
Guillaume Gomez
9be9d728e9 Clean up E0727 explanation 2020-07-23 21:11:40 +02:00
Esteban Küber
889a4d9a0b Change error code number 2020-07-22 13:12:34 -07:00
Esteban Küber
7bf39fa9d9 Further tweak wording of E0759 and introduce E0767 2020-07-22 12:25:54 -07:00
Mark Rousskov
c5cc29b0e0 Parse rustc_deprecated as deprecated attribute 2020-07-20 21:22:14 -04:00
Gabriel Smith
69d5dd6a50 disallow non-static lifetimes in const generics
This has been put in place to patch over an ICE caused when we encounter
a non-static lifetime in a const generic during borrow checking. This
restriction may be relaxed in the future, but we need more discussion
before then, and in the meantime we should still deal with this ICE.

Fixes issue #60814
2020-07-19 12:52:36 -04:00
Vadim Petrochenkov
926ac5a2fd rustc_metadata: Remove some extra diagnostics for legacy plugins
They are deprecated so doing extra work for error recovery doesn't make sense
2020-07-18 14:04:41 +04:00
Manish Goregaokar
5bb9bef795
Rollup merge of #74398 - GuillaumeGomez:cleanup-e0723, r=Dylan-DPC
Clean up E0723 explanation

r? @Dylan-DPC
2020-07-16 17:09:06 -07:00
Manish Goregaokar
6ef0dfa42f
Rollup merge of #74159 - lcnr:const-generic-ty-decl, r=varkor
forbid generic params in the type of const params

implements and closes #74152

fixes #74101, closes #71169, fixes #73491, closes #62878

@eddyb and I talked [on zulip](https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/type.20of.20const.20parameters/near/203405696) about this and we probably want to also forbid generic consts in the default
type of a parameter, e.g. `struct Foo<T, U = [u8; std::mem::size_of::<T>()]>`, this is currently still allowed
and I will probably fix that in a followup PR.

r? @varkor @eddyb
2020-07-16 11:18:46 -07:00
Manish Goregaokar
cc38f6fbf7
Rollup merge of #73835 - GuillaumeGomez:cleanup-e0710, r=Dylan-DPC
Clean up E0710 explanation

r? @Dylan-DPC
2020-07-16 11:18:33 -07:00
Manish Goregaokar
6309d9fb58
Rollup merge of #73794 - GuillaumeGomez:cleanup-e0705, r=Dylan-DPC
Small cleanup for E0705 explanation

r? @Dylan-DPC
2020-07-16 11:18:29 -07:00
Guillaume Gomez
03bbe9d2c9 Clean up E0723 explanation 2020-07-16 17:04:34 +02:00
Bastian Kauschke
338a27174a forbid generic params in the type of const params 2020-07-16 11:13:05 +02:00
Manish Goregaokar
1527126e07
Rollup merge of #73959 - GuillaumeGomez:cleanup-e0716, r=Dylan-DPC
Clean up E0716 explanation

r? @Dylan-DPC
2020-07-15 11:01:11 -07:00
Manish Goregaokar
7307af1f1c
Rollup merge of #73918 - GuillaumeGomez:cleanup-e0715, r=Dylan-DPC
Clean up E0715 explanation

r? @Dylan-DPC
2020-07-15 11:01:08 -07:00
Manish Goregaokar
b9a0f5803e
Rollup merge of #74173 - estebank:struct-pat-as-enum, r=petrochenkov
Detect tuple struct incorrectly used as struct pat

Subpart of #74005.

r? @petrochenkov
2020-07-14 07:39:02 -07:00
Manish Goregaokar
5e61827dd3
Rollup merge of #73720 - GuillaumeGomez:cleanup-e0704, r=Dylan-DPC
Clean up E0704 error explanation

r? @Dylan-DPC
2020-07-14 07:38:53 -07:00
Manish Goregaokar
9a1df31d55
Rollup merge of #74286 - PankajChaudhary5:E0688, r=GuillaumeGomez
Added detailed error code explanation for issue E0688 in Rust compiler.

Added proper error explanation for issue E0688 in the Rust compiler.
Error Code E0688

Sub Part of Issue #61137

r? @GuillaumeGomez
2020-07-13 22:23:15 -07:00
Manish Goregaokar
549aa03d86
Rollup merge of #74123 - GuillaumeGomez:cleanup-e0718, r=pickfire
clean up E0718 explanation

r? @Dylan-DPC
2020-07-13 22:23:10 -07:00
Pankaj Chaudhary
bc2b37aad7 Merge branch 'master' into E0688 2020-07-13 14:57:22 +05:30
PankajChaudhary5
e3ae4c7345 Added proper explanation of ErrorCode-E0688 2020-07-13 14:05:48 +05:30
Esteban Küber
5daedea3db Detect tuple struct incorrectly used as struct pat 2020-07-12 10:34:48 -07:00
Guillaume Gomez
633d1a5af9 Clean up E0720 explanation 2020-07-12 14:15:39 +02:00
Guillaume Gomez
2ba68f1888 Clean up E0719 explanation 2020-07-11 18:10:57 +02:00
Guillaume Gomez
4728438344
Improve wording 2020-07-11 17:34:11 +02:00
Tamir Duberstein
1e567c1168
Avoid "blacklist"
Other terms are more inclusive and precise.

Clippy still has a lint named "blacklisted-name", but renaming it would
be a breaking change, so is left for future work.

The target configuration option "abi-blacklist" has been depreciated and
renamed to "unsupported-abis". The old name continues to work.
2020-07-08 12:08:27 -04:00
Guillaume Gomez
00980b6ccd clean up E0718 explanation 2020-07-07 14:13:03 +02:00
bors
51eeabf505 Auto merge of #73562 - poliorcetics:e0432-to-edition2018, r=GuillaumeGomez
Update E0432 long description with the separate behaviors of editions 2015 and 2018

Fixes #64668.

I restarted from the work done in #71413.
2020-07-07 09:22:57 +00:00
Guillaume Gomez
d64a4b57ae Create new E0768 error code for "no valid digits found for number" error 2020-07-04 00:15:29 +02:00
Guillaume Gomez
69d5fc1a9f Clean up E0710 explanation 2020-07-02 15:44:22 +02:00
David Wood
cb541dc12c
resolve: disallow label use through closure/async
This commit modifies resolve to disallow `break`/`continue` to labels
through closures or async blocks. This doesn't make sense and should
have been prohibited anyway.

Signed-off-by: David Wood <david@davidtw.co>
2020-07-02 13:48:32 +01:00
Guillaume Gomez
818aaa7b58 Clean up E0716 explanation 2020-07-02 13:15:05 +02:00
Manish Goregaokar
1b37bfa537
Rollup merge of #73892 - GuillaumeGomez:cleanup-e0712, r=Dylan-DPC
Clean up E0712 explanation

r? @Dylan-DPC
2020-07-01 20:36:00 -07:00
Manish Goregaokar
ae79c30d74
Rollup merge of #72445 - anp:stabilize-track-caller, r=oli-obk
Stabilize `#[track_caller]`.

# Stabilization Report

RFC: [2091]
Tracking issue: https://github.com/rust-lang/rust/issues/47809

## Summary

From the [rustc-dev-guide chapter][dev-guide]:

> Take this example program:

```rust
fn main() {
    let foo: Option<()> = None;
    foo.unwrap(); // this should produce a useful panic message!
}
```

> Prior to Rust 1.42, panics like this `unwrap()` printed a location in libcore:

```
$ rustc +1.41.0 example.rs; example.exe
thread 'main' panicked at 'called `Option::unwrap()` on a `None` value',...core\macros\mod.rs:15:40
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace.
```

> As of 1.42, we get a much more helpful message:

```
$ rustc +1.42.0 example.rs; example.exe
thread 'main' panicked at 'called `Option::unwrap()` on a `None` value', example.rs:3:5
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
```

> These error messages are achieved through a combination of changes to `panic!` internals to make use of `core::panic::Location::caller` and a number of `#[track_caller]` annotations in the standard library which propagate caller information.

The attribute adds an implicit caller location argument to the ABI of annotated functions, but does not affect the type or MIR of the function. We implement the feature entirely in codegen and in the const evaluator.

## Bottom Line

This PR stabilizes the use of `#[track_caller]` everywhere, including traits and extern blocks. It also stabilizes `core::panic::Location::caller`, although the use of that function in a const context remains gated by `#![feature(const_caller_location)]`.

The implementation for the feature already changed the output of panic messages for a number of std functions, as described in the [1.42 release announcement]. The attribute's use in `Index` and `IndexMut` traits is visible to users since 1.44.

## Tests

All of the tests for this feature live under [src/test/ui/rfc-2091-track-caller][tests] in the repo.

Noteworthy cases:

* [use of attr in std]
  * validates user-facing benefit of the feature
* [trait attribute inheritance]
  * covers subtle behavior designed during implementation and not RFC'd
* [const/codegen equivalence]
  * this was the result of a suspected edge case and investigation
* [diverging function support]
  * covers an unresolved question from the RFC
* [fn pointers and shims]
  * covers important potential sources of unsoundness

## Documentation

The rustc-dev-guide now has a chapter on [Implicit Caller Location][dev-guide].

I have an [open PR to the reference][attr-reference-pr] documenting the attribute.

The intrinsic's [wrapper] includes some examples as well.

## Implementation History

* 2019-10-02: [`#[track_caller]` feature gate (RFC 2091 1/N) #65037](https://github.com/rust-lang/rust/pull/65037)
  * Picked up the patch that @ayosec had started on the feature gate.
* 2019-10-13: [Add `Instance::resolve_for_fn_ptr` (RFC 2091 #2/N) #65182](https://github.com/rust-lang/rust/pull/65182)
* 2019-10-20: ~~[WIP Add MIR argument for #[track_caller] (RFC 2091 3/N) #65258](https://github.com/rust-lang/rust/pull/65258)~~
  * Abandoned approach to send location as a MIR argument.
* 2019-10-28: [`std::panic::Location` is a lang_item, add `core::intrinsics::caller_location` (RFC 2091 3/N) #65664](https://github.com/rust-lang/rust/pull/65664)
* 2019-12-07: [Implement #[track_caller] attribute. (RFC 2091 4/N) #65881](https://github.com/rust-lang/rust/pull/65881)
* 2020-01-04: [libstd uses `core::panic::Location` where possible. #67137](https://github.com/rust-lang/rust/pull/67137)
* 2020-01-08: [`Option::{expect,unwrap}` and `Result::{expect, expect_err, unwrap, unwrap_err}` have `#[track_caller]` #67887](https://github.com/rust-lang/rust/pull/67887)
* 2020-01-20: [Fix #[track_caller] and function pointers #68302](https://github.com/rust-lang/rust/pull/68302) (fixed #68178)
* 2020-03-23: [#[track_caller] in traits #69251](https://github.com/rust-lang/rust/pull/69251)
* 2020-03-24: [#[track_caller] on core::ops::{Index, IndexMut}. #70234](https://github.com/rust-lang/rust/pull/70234)
* 2020-04-08 [Support `#[track_caller]` on functions in `extern "Rust" { ... }` #70916](https://github.com/rust-lang/rust/pull/70916)

## Unresolveds

### From the RFC

> Currently the RFC simply prohibit applying #[track_caller] to trait methods as a future-proofing
> measure.

**Resolved.** See the dev-guide documentation and the tests section above.

> Diverging functions should be supported.

**Resolved.** See the tests section above.

> The closure foo::{{closure}} should inherit most attributes applied to the function foo, ...

**Resolved.** This unknown was related to specifics of the implementation which were made irrelevant by the final implementation.

### Binary Size

I [instrumented track_caller to use custom sections][measure-size] in a local build and discovered relatively minor binary size usage for the feature overall. I'm leaving the issue open to discuss whether we want to upstream custom section support.

There's an [open issue to discuss mitigation strategies][mitigate-size]. Some decisions remain about the "right" strategies to reduce size without overly constraining the compiler implementation. I'd be excited to see someone carry that work forward but my opinion is that we shouldn't block stabilization on implementing compiler flags for redaction.

### Specialization

There's an [open issue][specialization] on the semantics of the attribute in specialization chains. I'm inclined to move forward with stabilization without an exact resolution here given that specialization is itself unstable, but I also think it should be an easy question to resolve.

### Location only points to the start of a call span

https://github.com/rust-lang/rust/issues/69977 was resolved by https://github.com/rust-lang/rust/pull/73182, and the next step should probably be to [extend `Location` with a notion of the end of a call](https://github.com/rust-lang/rust/issues/73554).

### Regression of std's panic messages

#70963 should be resolved by serializing span hygeine to crate metadata: https://github.com/rust-lang/rust/issues/68686.

[2091]: https://github.com/rust-lang/rfcs/blob/master/text/2091-inline-semantic.md
[dev-guide]: https://rustc-dev-guide.rust-lang.org/codegen/implicit-caller-location.html
[specialization]: https://github.com/rust-lang/rust/issues/70293
[measure-size]: https://github.com/rust-lang/rust/issues/70579
[mitigate-size]: https://github.com/rust-lang/rust/issues/70580
[attr-reference-pr]: https://github.com/rust-lang/reference/pull/742
[wrapper]: https://doc.rust-lang.org/nightly/core/panic/struct.Location.html#method.caller
[tests]: https://github.com/rust-lang/rust/tree/master/src/test/ui/rfc-2091-track-caller
[const/codegen equivalence]: https://github.com/rust-lang/rust/blob/master/src/test/ui/rfc-2091-track-caller/caller-location-fnptr-rt-ctfe-equiv.rs
[diverging function support]: https://github.com/rust-lang/rust/blob/master/src/test/ui/rfc-2091-track-caller/diverging-caller-location.rs
[use of attr in std]: https://github.com/rust-lang/rust/blob/master/src/test/ui/rfc-2091-track-caller/std-panic-locations.rs
[fn pointers and shims]: https://github.com/rust-lang/rust/blob/master/src/test/ui/rfc-2091-track-caller/tracked-fn-ptr-with-arg.rs
[trait attribute inheritance]: https://github.com/rust-lang/rust/blob/master/src/test/ui/rfc-2091-track-caller/tracked-trait-impls.rs
[1.42 release announcement]: https://blog.rust-lang.org/2020/03/12/Rust-1.42.html#useful-line-numbers-in-option-and-result-panic-messages
2020-07-01 07:42:33 -07:00