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101 Commits

Author SHA1 Message Date
bors
34f2839683 Auto merge of #95565 - jackh726:remove-borrowck-mode, r=nikomatsakis
Remove migrate borrowck mode

Closes #58781
Closes #43234

# Stabilization proposal

This PR proposes the stabilization of `#![feature(nll)]` and the removal of `-Z borrowck`. Current borrow checking behavior of item bodies is currently done by first infering regions *lexically* and reporting any errors during HIR type checking. If there *are* any errors, then MIR borrowck (NLL) never occurs. If there *aren't* any errors, then MIR borrowck happens and any errors there would be reported. This PR removes the lexical region check of item bodies entirely and only uses MIR borrowck. Because MIR borrowck could never *not* be run for a compiled program, this should not break any programs. It does, however, change diagnostics significantly and allows a slightly larger set of programs to compile.

Tracking issue: #43234
RFC: https://github.com/rust-lang/rfcs/blob/master/text/2094-nll.md
Version: 1.63 (2022-06-30 => beta, 2022-08-11 => stable).

## Motivation

Over time, the Rust borrow checker has become "smarter" and thus allowed more programs to compile. There have been three different implementations: AST borrowck, MIR borrowck, and polonius (well, in progress). Additionally, there is the "lexical region resolver", which (roughly) solves the constraints generated through HIR typeck. It is not a full borrow checker, but does emit some errors.

The AST borrowck was the original implementation of the borrow checker and was part of the initially stabilized Rust 1.0. In mid 2017, work began to implement the current MIR borrow checker and that effort ompleted by the end of 2017, for the most part. During 2018, efforts were made to migrate away from the AST borrow checker to the MIR borrow checker - eventually culminating into "migrate" mode - where HIR typeck with lexical region resolving following by MIR borrow checking - being active by default in the 2018 edition.

In early 2019, migrate mode was turned on by default in the 2015 edition as well, but with MIR borrowck errors emitted as warnings. By late 2019, these warnings were upgraded to full errors. This was followed by the complete removal of the AST borrow checker.

In the period since, various errors emitted by the MIR borrow checker have been improved to the point that they are mostly the same or better than those emitted by the lexical region resolver.

While there do remain some degradations in errors (tracked under the [NLL-diagnostics tag](https://github.com/rust-lang/rust/issues?q=is%3Aopen+is%3Aissue+label%3ANLL-diagnostics), those are sufficiently small and rare enough that increased flexibility of MIR borrow check-only is now a worthwhile tradeoff.

## What is stabilized

As said previously, this does not fundamentally change the landscape of accepted programs. However, there are a [few](https://github.com/rust-lang/rust/issues?q=is%3Aopen+is%3Aissue+label%3ANLL-fixed-by-NLL) cases where programs can compile under `feature(nll)`, but not otherwise.

There are two notable patterns that are "fixed" by this stabilization. First, the `scoped_threads` feature, which is a continutation of a pre-1.0 API, can sometimes emit a [weird lifetime error](https://github.com/rust-lang/rust/issues/95527) without NLL. Second, actually seen in the standard library. In the `Extend` impl for `HashMap`, there is an implied bound of `K: 'a` that is available with NLL on but not without - this is utilized in the impl.

As mentioned before, there are a large number of diagnostic differences. Most of them are better, but some are worse. None are serious or happen often enough to need to block this PR. The biggest change is the loss of error code for a number of lifetime errors in favor of more general "lifetime may not live long enough" error. While this may *seem* bad, the former error codes were just attempts to somewhat-arbitrarily bin together lifetime errors of the same type; however, on paper, they end up being roughly the same with roughly the same kinds of solutions.

## What isn't stabilized

This PR does not completely remove the lexical region resolver. In the future, it may be possible to remove that (while still keeping HIR typeck) or to remove it together with HIR typeck.

## Tests

Many test outputs get updated by this PR. However, there are number of tests specifically geared towards NLL under `src/test/ui/nll`

## History

* On 2017-07-14, [tracking issue opened](https://github.com/rust-lang/rust/issues/43234)
* On 2017-07-20, [initial empty MIR pass added](https://github.com/rust-lang/rust/pull/43271)
* On 2017-08-29, [RFC opened](https://github.com/rust-lang/rfcs/pull/2094)
* On 2017-11-16, [Integrate MIR type-checker with NLL](https://github.com/rust-lang/rust/pull/45825)
* On 2017-12-20, [NLL feature complete](https://github.com/rust-lang/rust/pull/46862)
* On 2018-07-07, [Don't run AST borrowck on mir mode](https://github.com/rust-lang/rust/pull/52083)
* On 2018-07-27, [Add migrate mode](https://github.com/rust-lang/rust/pull/52681)
* On 2019-04-22, [Enable migrate mode on 2015 edition](https://github.com/rust-lang/rust/pull/59114)
* On 2019-08-26, [Don't downgrade errors on 2015 edition](https://github.com/rust-lang/rust/pull/64221)
* On 2019-08-27, [Remove AST borrowck](https://github.com/rust-lang/rust/pull/64790)
2022-06-07 05:04:14 +00:00
Philipp Krones
f067783461 Merge commit 'd9ddce8a223cb9916389c039777b6966ea448dc8' into clippyup 2022-06-04 13:34:07 +02:00
Jack Huey
1fad95309b Fully stabilize NLL 2022-06-03 17:16:41 -04:00
xFrednet
4587b6628d Merge 'rust-clippy/master' into clippyup 2022-05-21 13:24:00 +02:00
Camille GILLOT
31825326e5 Bless clippy. 2022-05-11 18:51:14 +02:00
flip1995
7cd86aa1be Merge commit '7c21f91b15b7604f818565646b686d90f99d1baf' into clippyup 2022-05-05 15:12:52 +01:00
flip1995
71131351de Merge commit '984330a6ee3c4d15626685d6dc8b7b759ff630bd' into clippyup 2022-04-08 10:06:10 +01:00
Oli Scherer
6fc3850847 update clippy stderr file 2022-03-24 11:27:07 +00:00
Esteban Kuber
90da7cdd41 Do not point at whole file missing fn main
Only point at the end of the crate. We could try making it point at the
beginning of the crate, but that is confused with `DUMMY_SP`, causing
the output to be *worse*.

This change will make it so that VSCode will *not* underline the whole
file when `main` is missing, so other errors will be visible.
2022-03-05 02:42:55 +00:00
flip1995
611d039814 Merge commit '57b3c4b90f4346b3990c1be387c3b3ca7b78412c' into clippyup 2022-02-10 18:40:06 +01:00
flip1995
97ab44ca97 Merge commit '0eff589afc83e21a03a168497bbab6b4dfbb4ef6' into clippyup 2021-12-30 15:10:43 +01:00
Jacob Pratt
f8817f63e1 Stabilize destructuring_assignment 2021-12-14 22:38:51 -05:00
flip1995
8fea1d94f3 Merge commit 'a5d597637dcb78dc73f93561ce474f23d4177c35' into clippyup 2021-12-06 12:33:31 +01:00
Aaron Hill
3c8b644d0d Only check for errors in predicate when skipping impl assembly
Prior to PR #91205, checking for errors in the overall obligation
would check checking the `ParamEnv`, due to an incorrect
`super_visit_with` impl. With this bug fixed, we will now
bail out of impl candidate assembly if the `ParamEnv` contains
any error types.

In practice, this appears to be overly conservative - when an error
occurs early in compilation, we end up giving up early for some
predicates that we could have successfully evaluated without overflow.
By only checking for errors in the predicate itself, we avoid causing
additional spurious 'type annotations needed' errors after a 'real'
error has already occurred.

With this PR, the diagnostic changes caused by PR #91205 are reverted.
2021-11-27 11:33:55 -06:00
bors
6b997b6576 Auto merge of #91205 - Aaron1011:visit_param_env, r=lcnr
Visit `param_env` field in Obligation's `TypeFoldable` impl

This oversight appears to have gone unnoticed for a long time
without causing issues, but it should still be fixed.
2021-11-26 09:55:06 +00:00
Aaron Hill
9274ec5691 Visit param_env field in Obligation's TypeFoldable impl
This oversight appears to have gone unnoticed for a long time
without causing issues, but it should still be fixed.
2021-11-25 15:33:37 -06:00
Esteban Kuber
5fc61a24c4 Fix clippy test 2021-11-25 18:39:32 +00:00
flip1995
e674d0a599 Merge commit 'e18101137866b79045fee0ef996e696e68c920b4' into clippyup 2021-11-04 12:52:36 +00:00
Cameron Steffen
0a23fff82d Fix clippy with changed macro statement spans 2021-10-15 02:36:58 -05:00
Oli Scherer
049ab82662 Update clippy ui output 2021-10-13 11:06:14 +00:00
flip1995
5cf4984872 Merge commit 'b7f3f7f6082679da2da9a0b3faf1b5adef3afd3b' into clippyup 2021-10-07 11:21:30 +02:00
Cameron Steffen
9c2d52fabe Add desugaring mark to while loop 2021-10-02 17:41:14 -05:00
lcnr
fd8b150959 feature(const_generics) -> feature(const_param_types) 2021-08-30 11:00:21 +02:00
Caio
b97d4c062b Introduce hir::ExprKind::Let - Take 2 2021-08-15 16:18:26 -03:00
Guillaume Gomez
fd5427b686 Rollup merge of #87885 - m-ou-se:edition-guide-links, r=rylev
Link to edition guide instead of issues for 2021 lints.

This changes the 2021 lints to not link to github issues, but to the edition guide instead.

Fixes  #86996
2021-08-12 13:25:07 +02:00
Mara Bos
8e563b5468 Bless clippy tests. 2021-08-12 10:48:16 +02:00
Esteban Kuber
652b6a771f update clippy 2021-08-11 14:21:33 +00:00
Esteban Küber
9a6ae783d4 Use multispan suggestions more often
* Use more accurate span for `async move` suggestion
* Use more accurate span for deref suggestion
* Use `multipart_suggestion` more often
2021-07-30 09:26:31 -07:00
flip1995
884ef4c287 Merge commit '4c41a222ca5d1325fb4b6709395bd06e766cc042' into clippyup 2021-07-19 11:52:05 +02:00
flip1995
1d084b13a5 Merge commit '54a20a02ecd0e1352a871aa0990bcc8b8b03173e' into clippyup 2021-07-15 10:44:10 +02:00
Ryan Levick
abc9a46868 Fix clippy test 2021-06-25 15:29:14 +02:00
flip1995
6c27482115 Merge commit '3ae8faff4d46ad92f194c2a4b941c3152a701b31' into clippyup 2021-06-03 08:41:37 +02:00
flip1995
97705b7ea6 Merge commit '9e3cd88718cd1912a515d26dbd9c4019fd5a9577' into clippyup 2021-05-20 13:07:57 +02:00
Aaron Hill
4698b366c4 Show macro name in 'this error originates in macro' message
When there are multiple macros in use, it can be difficult to tell
which one was responsible for producing an error.
2021-05-12 19:03:06 -04:00
flip1995
d605882023 Merge commit 'b71f3405606d49b9735606b479c3415a0ca9810f' into clippyup 2021-05-06 12:20:44 +02:00
bors
9735470bb4 Auto merge of #83213 - rylev:update-lints-to-errors, r=nikomatsakis
Update BARE_TRAIT_OBJECT and ELLIPSIS_INCLUSIVE_RANGE_PATTERNS to errors in Rust 2021

This addresses https://github.com/rust-lang/rust/pull/81244 by updating two lints to errors in the Rust 2021 edition.

r? `@estebank`
2021-05-04 08:09:23 +00:00
Ryan Levick
6ddd3c9e36 Fix clippy error 2021-04-29 18:37:22 +02:00
flip1995
ae72f1adb9 Merge commit '7c7683c8efe447b251d6c5ca6cce51233060f6e8' into clippyup 2021-04-27 16:55:11 +02:00
flip1995
02bf692169 Merge commit '98e2b9f25b6db4b2680a3d388456d9f95cb28344' into clippyup 2021-04-22 11:31:13 +02:00
lcnr
419bf6bbd8 fix suggestion for unsized function parameters 2021-04-19 20:06:19 +02:00
flip1995
f6d1f368db Merge commit 'b40ea209e7f14c8193ddfc98143967b6a2f4f5c9' into clippyup 2021-04-08 17:50:13 +02:00
flip1995
f2f2a005b4 Merge commit '6ed6f1e6a1a8f414ba7e6d9b8222e7e5a1686e42' into clippyup 2021-03-12 15:30:50 +01:00
flip1995
f64149dd04 Merge commit '928e72dd10749875cbd412f74bfbfd7765dbcd8a' into clippyup 2021-02-25 11:25:22 +01:00
flip1995
ac912be984 Merge commit '95c0459217d1661edfa794c8bb122452b92fb485' into clippyup 2021-01-30 18:06:34 +01:00
bors
39aca5ff9f Auto merge of #78399 - vn-ki:gsgdt-graphviz, r=oli-obk
make MIR graphviz generation use gsgdt

gsgdt [https://crates.io/crates/gsgdt] is a crate which provides an
interface for stringly typed graphs. It also provides generation of
graphviz dot format from said graph.

This is the first in a series of PRs on moving graphviz code out of rustc into normal crates and then implementating graph diffing on top of these crates.

r? `@oli-obk`
2020-12-15 22:00:02 +00:00
Vishnunarayan K I
4e14c05976 fix clippy test 2020-12-05 20:21:21 +05:30
bors
3be53bc45a Auto merge of #79329 - camelid:int-lit-suffix-error, r=davidtwco
Update error to reflect that integer literals can have float suffixes

For example, `1` is parsed as an integer literal, but it can be turned
into a float with the suffix `f32`. Now the error calls them "numeric
literals" and notes that you can add a float suffix since they can be
either integers or floats.
2020-11-30 01:42:14 +00:00
Camelid
2347eac4cc Update error to reflect that integer literals can have float suffixes
For example, `1` is parsed as an integer literal, but it can be turned
into a float with the suffix `f32`. Now the error calls them "numeric
literals" and notes that you can add a float suffix since they can be
either integers or floats.
2020-11-27 19:08:24 -08:00
flip1995
284c359c61 Fix ICE in utils::implements_trait
This only happend when debug_assertions were enabled in rustc
2020-11-23 13:52:27 +01:00
flip1995
d3d2018ead Merge commit '3e7c6dec244539970b593824334876f8b6ed0b18' into clippyup 2020-11-23 13:51:04 +01:00