Commit Graph

313 Commits

Author SHA1 Message Date
bors
928783de66 Auto merge of #91799 - matthiaskrgr:rollup-b38xx6i, r=matthiaskrgr
Rollup of 6 pull requests

Successful merges:

 - #83174 (Suggest using a temporary variable to fix borrowck errors)
 - #89734 (Point at capture points for non-`'static` reference crossing a `yield` point)
 - #90270 (Make `Borrow` and `BorrowMut` impls `const`)
 - #90741 (Const `Option::cloned`)
 - #91548 (Add spin_loop hint for RISC-V architecture)
 - #91721 (Minor improvements to `future::join!`'s implementation)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2021-12-11 18:56:59 +00:00
Matthias Krüger
7bba5c163c
Rollup merge of #89734 - estebank:issue-72312, r=nikomatsakis
Point at capture points for non-`'static` reference crossing a `yield` point

```
error[E0759]: `self` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
  --> $DIR/issue-72312.rs:10:24
   |
LL |     pub async fn start(&self) {
   |                        ^^^^^ this data with an anonymous lifetime `'_`...
...
LL |         require_static(async move {
   |         -------------- ...is required to live as long as `'static` here...
LL |             &self;
   |             ----- ...and is captured here
   |
note: `'static` lifetime requirement introduced by this trait bound
  --> $DIR/issue-72312.rs:2:22
   |
LL | fn require_static<T: 'static>(val: T) -> T {
   |                      ^^^^^^^

error: aborting due to previous error

For more information about this error, try `rustc --explain E0759`.
```

Fix #72312.
2021-12-11 17:35:23 +01:00
Noah Lev
e27315268b Suggest using a temporary variable to fix borrowck errors
In Rust, nesting method calls with both require `&mut` access to `self`
produces a borrow-check error:

    error[E0499]: cannot borrow `*self` as mutable more than once at a time
     --> src/lib.rs:7:14
      |
    7 |     self.foo(self.bar());
      |     ---------^^^^^^^^^^-
      |     |    |   |
      |     |    |   second mutable borrow occurs here
      |     |    first borrow later used by call
      |     first mutable borrow occurs here

That's because Rust has a left-to-right evaluation order, and the method
receiver is passed first. Thus, the argument to the method cannot then
mutate `self`.

There's an easy solution to this error: just extract a local variable
for the inner argument:

    let tmp = self.bar();
    self.foo(tmp);

However, the error doesn't give any suggestion of how to solve the
problem. As a result, new users may assume that it's impossible to
express their code correctly and get stuck.

This commit adds a (non-structured) suggestion to extract a local
variable for the inner argument to solve the error. The suggestion uses
heuristics that eliminate most false positives, though there are a few
false negatives (cases where the suggestion should be emitted but is
not). Those other cases can be implemented in a future change.
2021-12-10 14:34:00 -08:00
Esteban Kuber
d10fe26f39 Point at capture points for non-'static reference crossing a yield point
```
error[E0759]: `self` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
  --> $DIR/issue-72312.rs:10:24
   |
LL |     pub async fn start(&self) {
   |                        ^^^^^ this data with an anonymous lifetime `'_`...
...
LL |         require_static(async move {
   |         -------------- ...is required to live as long as `'static` here...
LL |             &self;
   |             ----- ...and is captured here
   |
note: `'static` lifetime requirement introduced by this trait bound
  --> $DIR/issue-72312.rs:2:22
   |
LL | fn require_static<T: 'static>(val: T) -> T {
   |                      ^^^^^^^

error: aborting due to previous error

For more information about this error, try `rustc --explain E0759`.
```

Fix #72312.
2021-12-10 03:08:22 +00:00
Camille GILLOT
8576ab45e4 Store impl_trait_fn inside OpaqueTyOrigin. 2021-12-07 21:30:45 +01:00
bors
887999d163 Auto merge of #88439 - cynecx:unwind_asm, r=Amanieu
Unwinding support for inline assembly

r? `@Amanieu`
2021-12-04 05:59:16 +00:00
Matthias Krüger
df51bffe6b
Rollup merge of #91488 - compiler-errors:issue-91477, r=estebank
Fix ICE when `yield`ing in function returning `impl Trait`

Change an assert to a `delay_span_bug` and remove an unwrap, that should fix it.

Fixes #91477
2021-12-04 02:26:26 +01:00
Amanieu d'Antras
940b2eabad Add initial AST and MIR support for unwinding from inline assembly 2021-12-03 23:51:46 +01:00
Santiago Pastorino
85b723c4e6
Revert "Auto merge of #91354 - fee1-dead:const_env, r=spastorino"
This reverts commit 18bb8c61a9, reversing
changes made to d9baa36190.
2021-12-03 10:11:21 -03:00
Michael Goulet
7c108ababc Fix ICE when yielding in fn returning impl Trait 2021-12-02 22:36:05 -08:00
Matthias Krüger
b56e3d955a
Rollup merge of #91321 - matthewjasper:constaint-placeholders, r=jackh726
Handle placeholder regions in NLL type outlive constraints

Closes #76168
2021-12-02 22:16:09 +01:00
bors
e5038e2099 Auto merge of #91455 - matthiaskrgr:rollup-gix2hy6, r=matthiaskrgr
Rollup of 4 iffy pull requests

Successful merges:

 - #89234 (Disallow non-c-like but "fieldless" ADTs from being casted to integer if they use arbitrary enum discriminant)
 - #91045 (Issue 90702 fix: Stop treating some crate loading failures as fatal errors)
 - #91394 (Bump stage0 compiler)
 - #91411 (Enable svh tests on msvc)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2021-12-02 14:53:20 +00:00
Matthias Krüger
d96ce3ea8e
Rollup merge of #91394 - Mark-Simulacrum:bump-stage0, r=pietroalbini
Bump stage0 compiler

r? `@pietroalbini` (or anyone else)
2021-12-02 15:52:03 +01:00
bors
18bb8c61a9 Auto merge of #91354 - fee1-dead:const_env, r=spastorino
Cleanup: Eliminate ConstnessAnd

This is almost a behaviour-free change and purely a refactoring. "almost" because we appear to be using the wrong ParamEnv somewhere already, and this is now exposed by failing a test using the unstable `~const` feature.

We most definitely need to review all `without_const` and at some point should probably get rid of many of them by using `TraitPredicate` instead of `TraitRef`.

This is a continuation of https://github.com/rust-lang/rust/pull/90274.

r? `@oli-obk`

cc `@spastorino` `@ecstatic-morse`
2021-12-02 11:48:58 +00:00
bors
76938d64a4 Auto merge of #90446 - cjgillot:late-elided, r=jackh726
Lint elided lifetimes in path during lifetime resolution.

The lifetime elision lint is known to be brittle and can be redundant with later lifetime resolution errors. This PR aims to remove the redundancy by performing the lint after lifetime resolution.

This PR proposes to carry the information that an elision should be linted against by using a special `LifetimeName`. I am not certain this is the best solution, but it is certainly the easiest.

Fixes https://github.com/rust-lang/rust/issues/60199
Fixes https://github.com/rust-lang/rust/issues/55768
Fixes https://github.com/rust-lang/rust/issues/63110
Fixes https://github.com/rust-lang/rust/issues/71957
2021-12-01 23:22:43 +00:00
Matthias Krüger
a4f46742c2
Rollup merge of #90985 - camsteffen:diag-name-usage, r=jackh726
Use `get_diagnostic_name` more
2021-12-01 10:50:18 +01:00
Matthias Krüger
dc78cd4c61
Rollup merge of #91294 - cjgillot:process-elem, r=jackh726
Visit type in process_projection_elem.

Instead of reimplementing it for each visitor.
2021-11-30 23:43:31 +01:00
Camille GILLOT
aa2450f41b Merge Implicit and ImplicitMissing. 2021-11-30 22:56:47 +01:00
Camille GILLOT
5ea7ea8a57 Lint elided lifetimes in path during lifetime resolution. 2021-11-30 22:55:07 +01:00
Mark Rousskov
971c549ca3 re-format with new rustfmt 2021-11-30 13:08:41 -05:00
Mark Rousskov
b221c877e8 Apply cfg-bootstrap switch 2021-11-30 10:51:42 -05:00
Yuki Okushi
6e7cf2e88b
Rollup merge of #91243 - jackh726:issue-91068, r=nikomatsakis
Don't treat unnormalized function arguments as well-formed

Partial revert of #88312

r? ``@pnkfelix``
cc ``@nikomatsakis``
2021-11-30 17:29:06 +09:00
Oli Scherer
a9a79f657c
Completely remove ConstnessAnd 2021-11-29 21:19:49 +08:00
Camille GILLOT
29b30a9bd2 Visit type in process_projection_elem. 2021-11-27 17:39:27 +01:00
Matthew Jasper
2a83c11d4d Handle placeholder regions in NLL type outlive constraints 2021-11-26 22:06:08 +00:00
jackh726
eeaa215f85 Don't treat unnormalized function arguments as well-formed 2021-11-25 21:16:27 -05:00
Michael Goulet
718a3b1f2d Fix issue 91206 2021-11-25 16:34:30 +00:00
bors
8a48b376d5 Auto merge of #90491 - Mark-Simulacrum:push-pred-faster, r=matthewjasper
Optimize live point computation

This refactors the live-point computation to lower per-MIR-instruction costs by operating on a largely per-block level. This doesn't fundamentally change the number of operations necessary, but it greatly improves the practical performance by aggregating bit manipulation into ranges rather than single-bit; this scales much better with larger blocks.

On the benchmark provided in #90445, with 100,000 array elements, walltime for a check build is improved from 143 seconds to 15.

I consider the tiny losses here acceptable given the many small wins on real world benchmarks and large wins on stress tests. The new code scales much better, but on some subset of inputs the slightly higher constant overheads decrease performance somewhat. Overall though, this is expected to be a big win for pathological cases (as illustrated by the test case motivating this work) and largely not material for non-pathological cases. I consider the new code somewhat easier to follow, too.
2021-11-24 15:51:46 +00:00
Cameron Steffen
9c83f8c4d1 Simplify for loop desugar 2021-11-21 08:15:21 -06:00
Cameron Steffen
dec40530f7 Use get_diagnostic_name more 2021-11-16 17:14:18 -06:00
Yuki Okushi
21bff4a4c1
Rollup merge of #90801 - b-naber:missing_normalization_equate_inputs_output, r=jackh726
Normalize both arguments of `equate_normalized_input_or_output`

Fixes https://github.com/rust-lang/rust/issues/90638
Fixes https://github.com/rust-lang/rust/issues/90612

Temporary fix for a more complex underlying problem stemming from an inability to normalize closure substs during typecheck.

r? ````@jackh726````
2021-11-16 15:59:39 +09:00
Josh Triplett
8c9bfaa5f3 Stabilize format_args_capture
Works as expected, and there are widespread reports of success with it,
as well as interest in it.
2021-11-15 10:14:29 +01:00
b-naber
26ca71fdb2 normalize argument b in equate_normalized_inputs_output 2021-11-11 23:54:15 +01:00
Matthias Krüger
fd74c93403
Rollup merge of #89561 - nbdd0121:const_typeck, r=nikomatsakis
Type inference for inline consts

Fixes #78132
Fixes #78174
Fixes #81857
Fixes #89964

Perform type checking/inference of inline consts in the same context as the outer def, similar to what is currently done to closure.

Doing so would require `closure_base_def_id` of the inline const to return the outer def, and since `closure_base_def_id` can be called on non-local crate (and thus have no HIR available), a new `DefKind` is created for inline consts.

The type of the generated anon const can capture lifetime of outer def, so we couldn't just use the typeck result as the type of the inline const's def. Closure has a similar issue, and it uses extra type params `CK, CS, U` to capture closure kind, input/output signature and upvars. I use a similar approach for inline consts, letting it have an extra type param `R`, and then `typeof(InlineConst<[paremt generics], R>)` would just be `R`. In borrowck region requirements are also propagated to the outer MIR body just like it's currently done for closure.

With this PR, inline consts in expression position are quitely usable now; however the usage in pattern position is still incomplete -- since those does not remain in the MIR borrowck couldn't verify the lifetime there. I have left an ignored test as a FIXME.

Some disucssions can be found on [this Zulip thread](https://rust-lang.zulipchat.com/#narrow/stream/260443-project-const-generics/topic/inline.20consts.20typeck).
cc `````@spastorino````` `````@lcnr`````
r? `````@nikomatsakis`````

`````@rustbot````` label A-inference F-inline_const T-compiler
2021-11-09 19:00:40 +01:00
Deadbeef
f1126f1272
Make select_* methods return Vec for TraitEngine 2021-11-08 23:35:23 +08:00
Matthias Krüger
5c454551da more clippy fixes 2021-11-07 16:59:05 +01:00
Gary Guo
c4103d438f Rename functions reflect that inline const is also "typeck_child" 2021-11-07 04:00:34 +00:00
Gary Guo
ff055e2135 Ensure closure requirements are proven for inline const 2021-11-07 04:00:34 +00:00
Gary Guo
468192a9c5 Implement type inference for inline consts
In most cases it is handled in the same way as closures.
2021-11-07 04:00:32 +00:00
Matthias Krüger
0a5640b55f use matches!() macro in more places 2021-11-06 16:13:14 +01:00
Mark Rousskov
03afb61b53 Optimize live point computation
This is just replicating the previous algorithm, but taking advantage of the
bitset structures to optimize into tighter and better optimized loops.
Particularly advantageous on enormous MIR blocks, which are relatively rare in
practice.
2021-11-03 11:24:59 -04:00
bors
88a5a984fe Auto merge of #90380 - Mark-Simulacrum:revert-89558-query-stable-lint, r=lcnr
Revert "Add rustc lint, warning when iterating over hashmaps"

Fixes perf regressions introduced in https://github.com/rust-lang/rust/pull/90235 by temporarily reverting the relevant PR.
2021-10-29 04:55:51 +00:00
bors
df76418f1e Auto merge of #90387 - matthiaskrgr:rollup-b2x8v0x, r=matthiaskrgr
Rollup of 3 pull requests

Successful merges:

 - #90082 (Fix minor typos)
 - #90336 (Remove extra lines in examples for `Duration::try_from_secs_*`)
 - #90376 (Various cleanups around opaque types)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2021-10-28 22:44:45 +00:00
bors
c390d69a61 Auto merge of #90281 - xldenis:public-borrow-set, r=nikomatsakis
Add BorrowSet to public api

This PR adds `BorrowSet` to the public api so that verification tools can obtain the activation and reservation points of two phase borrows without having to redo calculations themselves (and thus potentially differently from rustc).

Turns out we already can obtain `MoveData` thanks to the public `HasMoveData` trait, so constructing a `BorrowSet` should not provide much of an issue. However, I can't speak to the soundness of this approach, is it safe to take an under-approximation of `MoveData`?

r? `@nikomatsakis`
2021-10-28 19:34:01 +00:00
Mark Rousskov
3215eeb99f
Revert "Add rustc lint, warning when iterating over hashmaps" 2021-10-28 11:01:42 -04:00
Oli Scherer
bc552fc417 Move instantiate_opaque_types to rustc_infer.
It does not depend on anything from rustc_trait_selection anymore.
2021-10-28 14:12:24 +00:00
Xavier Denis
9894a9a716 Add BorrowSet to public api 2021-10-25 22:16:07 +02:00
bors
235d9853d8 Auto merge of #90042 - pietroalbini:1.56-master, r=Mark-Simulacrum
Bump bootstrap compiler to 1.57

Fixes https://github.com/rust-lang/rust/issues/90152

r? `@Mark-Simulacrum`
2021-10-25 11:31:47 +00:00
Matthias Krüger
87822b27ee
Rollup merge of #89558 - lcnr:query-stable-lint, r=estebank
Add rustc lint, warning when iterating over hashmaps

r? rust-lang/wg-incr-comp
2021-10-24 15:48:42 +02:00
Pietro Albini
b63ab8005a update cfg(bootstrap) 2021-10-23 21:55:57 -04:00
bors
aa5740c715 Auto merge of #90104 - spastorino:coherence-for-negative-trait, r=nikomatsakis
Implement coherence checks for negative trait impls

The main purpose of this PR is to be able to [move Error trait to core](https://github.com/rust-lang/project-error-handling/issues/3).

This feature is necessary to handle the following from impl on box.

```rust
impl From<&str> for Box<dyn Error> { ... }
```

Without having negative traits affect coherence moving the error trait into `core` and moving that `From` impl to `alloc` will cause the from impl to no longer compiler because of a potential future incompatibility. The compiler indicates that `&str` _could_ introduce an `Error` impl in the future, and thus prevents the `From` impl in `alloc` that would cause overlap with `From<E: Error> for Box<dyn Error>`. Adding `impl !Error for &str {}` with the negative trait coherence feature will disable this error by encoding a stability guarantee that `&str` will never implement `Error`, making the `From` impl compile.

We would have this in `alloc`:

```rust
impl From<&str> for Box<dyn Error> {} // A
impl<E> From<E> for Box<dyn Error> where E: Error {} // B
```

and this in `core`:

```rust
trait Error {}
impl !Error for &str {}
```

r? `@nikomatsakis`

This PR was built on top of `@yaahc` PR #85764.

Language team proposal: to https://github.com/rust-lang/lang-team/issues/96
2021-10-23 12:51:15 +00:00
Yuki Okushi
91fb223f59
Rollup merge of #89895 - camsteffen:for-loop-head-span, r=davidtwco
Don't mark for loop iter expression as desugared

We typically don't mark spans of lowered things as desugared. This helps Clippy rightly discern when code is (not) from expansion. This was discovered by ``@flip1995`` at https://github.com/rust-lang/rust-clippy/pull/7789#issuecomment-939289501.
2021-10-22 19:42:45 +09:00
Gary Guo
1b7f5a3818 Remove NullOp::Box 2021-10-20 19:42:35 +01:00
Santiago Pastorino
6975afd141
Add polarity to TraitPredicate 2021-10-20 12:10:41 -03:00
bors
1af55d19c7 Auto merge of #89933 - est31:let_else, r=michaelwoerister
Adopt let_else across the compiler

This performs a substitution of code following the pattern:

```
let <id> = if let <pat> = ... { identity } else { ... : ! };
```

To simplify it to:

```
let <pat> = ... { identity } else { ... : ! };
```

By adopting the `let_else` feature (cc #87335).

The PR also updates the syn crate because the currently used version of the crate doesn't support `let_else` syntax yet.

Note: Generally I'm the person who *removes* usages of unstable features from the compiler, not adds more usages of them, but in this instance I think it hopefully helps the feature get stabilized sooner and in a better state. I have written a [comment](https://github.com/rust-lang/rust/issues/87335#issuecomment-944846205) on the tracking issue about my experience and what I feel could be improved before stabilization of `let_else`.
2021-10-19 14:41:39 +00:00
bors
ec724ac075 Auto merge of #89229 - oli-obk:i_love_inferctxt, r=jackh726
Remove redundant member-constraint check

impl trait will, for each lifetime in the hidden type, register a "member constraint" that says the lifetime must be equal or outlive one of the lifetimes of the impl trait. These member constraints will be solved by borrowck

But, as you can see in the big red block of removed code, there was an ad-hoc check for member constraints happening at the site where they get registered. This check had some minor effects on diagnostics, but will fall down on its feet with my big type alias impl trait refactor. So we removed it and I pulled the removal out into a (hopefully) reviewable PR that works on master directly.
2021-10-18 23:02:53 +00:00
Yuki Okushi
bf7c32a447
Fix ICE with let...else and ref mut 2021-10-17 07:12:22 +09:00
est31
1418df5888 Adopt let_else across the compiler
This performs a substitution of code following the pattern:

let <id> = if let <pat> = ... { identity } else { ... : ! };

To simplify it to:

let <pat> = ... { identity } else { ... : ! };

By adopting the let_else feature.
2021-10-16 07:18:05 +02:00
Oli Scherer
3ea956b8c5 Remove a now-unused trait 2021-10-15 17:50:33 +00:00
Niko Matsakis
094a9c743e simplify constrain_opaque_types 2021-10-15 17:50:33 +00:00
Cameron Steffen
bd1a1e4f0d Don't mark for loop head span with desugaring 2021-10-15 08:04:50 -05:00
lcnr
00e5abe9b6 allow potential_query_instability everywhere 2021-10-15 10:58:18 +02:00
bors
0a56eb11fa Auto merge of #88698 - Noble-Mushtak:master, r=nikomatsakis,oli-obk
Add check that live_region is live in sanitize_promoted

This pull request fixes #88434 by adding a check in `sanitize_promoted` to ensure that only regions which are actually live are added to the `liveness_constraints` of the `BorrowCheckContext`.

To implement this change, I needed to add a method to `LivenessValues` which gets the elements contained by a region:

    /// Returns an iterator of all the elements contained by the region `r`
    crate fn get_elements(&self, row: N) -> impl Iterator<Item = Location> + '_

Then, inside `sanitize_promoted`, we check whether the iterator returned by this method is non-empty to ensure that the region is actually live at at least one location before adding that region to the `liveness_constraints` of the `BorrowCheckContext`.

This is my first pull request to the Rust repo, so any feedback on how I can improve this pull request or if there is a better way to fix this issue would be very appreciated.
2021-10-14 13:21:46 +00:00
Matthias Krüger
fde2412b23
Rollup merge of #89675 - oli-obk:type_checker, r=davidtwco
Re-use TypeChecker instead of passing around some of its fields

In the future (for lazy TAIT) we will need more of its fields, but even ignoring that, this change seems reasonable on its own to me.
2021-10-11 23:45:49 +02:00
Guillaume Gomez
836597a881
Rollup merge of #89649 - matthiaskrgr:clippycompl, r=jyn514
clippy::complexity fixes
2021-10-08 22:30:40 +02:00
Matthias Krüger
e6f77a1787 clippy::complexity fixes 2021-10-08 20:07:44 +02:00
Oli Scherer
49b06a2b60 Directly call relate_types function instead of having a method wrapper 2021-10-08 17:53:41 +00:00
Oli Scherer
597090ee14 Re-use TypeChecker instead of passing around some of its fields 2021-10-08 17:51:56 +00:00
Noble-Mushtak
8fc329f5d2 Add check that region is live in sanitize_promoted 2021-10-07 18:20:23 -04:00
Guillaume Gomez
0fbb011eb4
Rollup merge of #89615 - willcrichton:fix-get-body-with-borrowck-facts, r=oli-obk
Add InferCtxt::with_opaque_type_inference to get_body_with_borrowck_facts

`mir_borrowck` uses `with_opaque_type_inference` before calling `do_mir_borrowck`: 0eabf25b90/compiler/rustc_borrowck/src/lib.rs (L132)

However `get_body_with_borrowck_facts` does not. Therefore I get an ICE eg when calling this function on the bodies of an async function as described here: https://rust-lang.zulipchat.com/#narrow/stream/182449-t-compiler.2Fhelp/topic/.E2.9C.94.20ICE.20when.20using.20get_body_with_borrowck_facts.20with.20async

This change fixes that bug.

r? `@nikomatsakis`
2021-10-07 16:24:54 +02:00
Will Crichton
549a68b73e Add InferCtxt::with_opaque_type_inference to get_body_with_borrowck_facts 2021-10-06 19:07:56 -07:00
Aaron Hill
3c974adb4c
Note specific regions involved in 'borrowed data escapes' error
Fixes #67007

Currently, a 'borrowed data escapes' error does not mention
the specific lifetime involved (except indirectly through a suggestion
about adding a lifetime bound). We now explain the specific lifetime
relationship that failed to hold, which improves otherwise vague
error messages.
2021-10-05 13:25:03 -05:00
Manish Goregaokar
bf62c6d710
Rollup merge of #89504 - Aaron1011:rpit-nll-static, r=nikomatsakis
Don't suggest replacing region with 'static in NLL

Fixes #73159

This is similar to #69350 - if the user didn't initially
write out a 'static lifetime, adding 'static in response to
a lifetime error is usually the wrong thing to do.
2021-10-04 23:56:24 -07:00
Jubilee
9866b090f4
Rollup merge of #89508 - jhpratt:stabilize-const_panic, r=joshtriplett
Stabilize `const_panic`

Closes #51999

FCP completed in #89006

```@rustbot``` label +A-const-eval +A-const-fn +T-lang

cc ```@oli-obk``` for review (not `r?`'ing as not on lang team)
2021-10-04 13:58:17 -07:00
Jacob Pratt
bce8621983
Stabilize const_panic 2021-10-04 02:33:33 -04:00
Manish Goregaokar
5215b855b0
Rollup merge of #88481 - bjorn3:remove_feature_gates, r=cjgillot
Remove some feature gates

The first commit removes various feature gates that are unused. The second commit replaces some `Fn` implementations with `Iterator` implementations, which is much cleaner IMO. The third commit replaces an unboxed_closures feature gate with min_specialization. For some reason the unboxed_closures feature gate suppresses the min_specialization feature gate from triggering on an `TrustedStep` impl. The last comment just turns a regular comment into a doc comment as drive by cleanup. I can move it to a separate PR if preferred.
2021-10-03 23:13:20 -07:00
Aaron Hill
fdd8a0dde5
Don't suggest replacing region with 'static in NLL
Fixes #73159

This is similar to #69350 - if the user didn't initially
write out a 'static lifetime, adding 'static in response to
a lifetime error is usually the wrong thing to do.
2021-10-03 21:53:48 -05:00
bjorn3
9f4cb862ca Replace Fn impls with RPIT impls in rustc_index
This is cleaner and removes an unstable feature usage
2021-10-03 17:50:53 +02:00
Cameron Steffen
eec856bfbc Make diangostic item names consistent 2021-10-02 19:38:19 -05:00
Guillaume Gomez
759eba0a08 Fix clippy lints 2021-10-01 23:17:19 +02:00
Manish Goregaokar
8c5114b4e8
Rollup merge of #89327 - oli-obk:nll_diag_infer_vars, r=wesleywiser
Pick one possible lifetime in case there are multiple choices

In case a lifetime variable is created, but doesn't have an obvious lifetime in the list of named lifetimes that it should be inferred to, just pick the first one for the diagnostic.

This happens e.g. in

```rust
fn foo<'a, 'b>(a: Struct<'a>, b: Struct<'b>) -> impl Trait<'a, 'b> {
    if bar() { a } else { b }
}
```

where we get a lifetime variable that combines the lifetimes of `a` and `b` creating a lifetime that is the intersection of both. Right now the type system cannot express this and thus we get an error, but that error also can't express this.

I can also create an entirely new diagnostic that mentions all involved lifetimes, so it would actually mention `'a` and `'b` instead of just `'b`.
2021-09-30 23:41:08 -07:00
bors
6dc08b909b Auto merge of #87998 - nneonneo:master, r=oli-obk
Avoid spurious "previous iteration of loop" errors

Only follow backwards edges during `get_moved_indexes` if the move path is definitely initialized at loop entry. Otherwise, the error occurred prior to the loop, so we ignore the backwards edges to avoid generating misleading "value moved here, in previous iteration of loop" errors.

This patch also slightly improves the analysis of inits, including `NonPanicPathOnly` initializations (which are ignored by `drop_flag_effects::for_location_inits`). This is required for the definite initialization analysis, but may also help find certain skipped reinits in rare cases.

Patch passes all non-ignored src/test/ui testcases.

Fixes #72649.
2021-09-30 13:23:09 +00:00
Oli Scherer
87a4a79554 Pick one possible lifetime in case there are multiple choices 2021-09-28 16:24:13 +00:00
Oli Scherer
9b5aa063d8 More tracing instrumentation 2021-09-28 12:28:22 +00:00
Aaron Hill
41ad383e11
Remove DefId from ConstraintCategory::Predicate
This shirnks the size of `ConstraintCategory`, hopefully
fixing a performance regression.
2021-09-27 10:45:34 -05:00
Aaron Hill
93ab12eeab
Improve cause information for NLL higher-ranked errors
This PR has several interconnected pieces:

1. In some of the NLL region error code, we now pass
   around an `ObligationCause`, instead of just a plain `Span`.
   This gets forwarded into `fulfill_cx.register_predicate_obligation`
   during error reporting.
2. The general InferCtxt error reporting code is extended to
   handle `ObligationCauseCode::BindingObligation`
3. A new enum variant `ConstraintCategory::Predicate` is added.
   We try to avoid using this as the 'best blame constraint' - instead,
   we use it to enhance the `ObligationCause` of the `BlameConstraint`
   that we do end up choosing.

As a result, several NLL error messages now contain the same
"the lifetime requirement is introduced here" message as non-NLL
errors.

Having an `ObligationCause` available will likely prove useful
for future improvements to NLL error messages.
2021-09-27 10:23:45 -05:00
bors
e9f29a8519 Auto merge of #89030 - nbdd0121:box2, r=jonas-schievink
Introduce `Rvalue::ShallowInitBox`

Polished version of #88700.

Implements MCP rust-lang/compiler-team#460, and should allow #43596 to go forward.

In short, creating an empty box is split from a nullary-op `NullOp::Box` into two steps, first a call to `exchange_malloc`, then a `Rvalue::ShallowInitBox` which transmutes `*mut u8` to a shallow-initialized `Box<T>`. This allows the `exchange_malloc` call to unwind. Details can be found in the MCP.

`NullOp::Box` is not yet removed, purely to make reverting easier in case anything goes wrong as the result of this PR. If revert is needed a reversion of "Use Rvalue::ShallowInitBox for box expression" commit followed by a test bless should be sufficient.

Experiments in #88700 showed a very slight compile-time perf regression due to (supposedly) slightly more time spent in LLVM. We could omit unwind edge generation (in non-`oom=panic` case) in box expression MIR construction to restore perf; but I don't think it's necessary since runtime perf isn't affected and perf difference is rather small.
2021-09-25 11:01:13 +00:00
Gary Guo
c38da2e0a3 Introduce Rvalue::ShallowInitBox 2021-09-25 01:08:41 +01:00
Jubilee
ee2e97c416
Rollup merge of #89001 - jackh726:binder-cleanup, r=nikomatsakis
Be explicit about using Binder::dummy

This is somewhat of a late followup to the binder refactor PR. It removes `ToPredicate` and `ToPolyTraitImpls` that hide the use of `Binder::dummy`. While this does make code a bit more verbose, it allows us be more careful about where we create binders.

Another alternative here might be to add a new trait `ToBinder` or something with a `dummy()` fn. Which could still allow grepping but allows doing something like `trait_ref.dummy()` (but I also wonder if longer-term, it would be better to be even more explicit with a `bind_with_vars(ty::List::empty())` *but* that's not clear yet.

r? ``@nikomatsakis``
2021-09-24 11:40:11 -07:00
Oli Scherer
6067eadb65 Check that TAIT generics are fully generic in mir typeck instead of wf-check, as wf-check can by definition only check TAIT in return position and not account for TAITs defined in the body of the function 2021-09-23 13:35:16 +00:00
Mark Rousskov
c746be2219 Migrate to 2021 2021-09-20 22:21:42 -04:00
bors
0c0826c3e2 Auto merge of #88708 - Aaron1011:aggregate-usage, r=oli-obk
Add `ConstraintCategory::Usage` for handling aggregate construction

In some cases, we emit borrowcheck diagnostics pointing
at a particular field expression in a struct expression
(e.g. `MyStruct { field: my_expr }`). However, this
behavior currently relies on us choosing the
`ConstraintCategory::Boring` with the 'correct' span.
When adding additional variants to `ConstraintCategory`,
(or changing existing usages away from `ConstraintCategory::Boring`),
the current behavior can easily get broken, since a non-boring
constraint will get chosen over a boring one.

To make the diagnostic output less fragile, this commit
adds a `ConstraintCategory::Usage` variant. We use this variant
for the temporary assignments created for each field of
an aggregate we are constructing.

Using this new variant, we can emit a message mentioning
"this usage", emphasizing the fact that the error message
is related to the specific use site (in the struct expression).

This is preparation for additional work on improving NLL error messages
(see #57374)
2021-09-20 00:53:13 +00:00
bors
5438ee424c Auto merge of #88980 - tmiasko:instrument-debug, r=oli-obk
Use explicit log level in tracing instrument macro

Specify a log level in tracing instrument macro explicitly.

Additionally reduce the used log level from a default info level to a
debug level (all of those appear to be developer oriented logs, so there
should be no need to include them in release builds).
2021-09-18 06:11:02 +00:00
Guillaume Gomez
aed7f00097
Rollup merge of #87460 - FabianWolff:issue-87456, r=Aaron1011
Point to closure when emitting 'cannot move out' for captured variable

Attempts to fix #87456. The error message now points to the capturing closure, but I was not able to explain _why_ the closure implements `Fn` or `FnMut` (`TypeckResults::closure_kind_origins` did not contain anything for the closure in question).

cc `@Aaron1011`
2021-09-17 17:41:13 +02:00
bors
e36621057d Auto merge of #88719 - estebank:point-at-arg-for-obligation, r=nagisa
Point at argument instead of call for their obligations

When an obligation is introduced by a specific `fn` argument, point at
the argument instead of the `fn` call if the obligation fails to be
fulfilled.

Move the information about pointing at the call argument expression in
an unmet obligation span from the `FulfillmentError` to a new
`ObligationCauseCode`.

When giving an error about an obligation introduced by a function call
that an argument doesn't fulfill, and that argument is a block, add a
span_label pointing at the innermost tail expression.

Current output:

```
error[E0425]: cannot find value `x` in this scope
 --> f10.rs:4:14
  |
4 |         Some(x * 2)
  |              ^ not found in this scope

error[E0277]: expected a `FnOnce<({integer},)>` closure, found `Option<_>`
 --> f10.rs:2:31
  |
2 |       let p = Some(45).and_then({
  |  ______________________--------_^
  | |                      |
  | |                      required by a bound introduced by this call
3 | |         |x| println!("doubling {}", x);
4 | |         Some(x * 2)
  | |         -----------
5 | |     });
  | |_____^ expected an `FnOnce<({integer},)>` closure, found `Option<_>`
  |
  = help: the trait `FnOnce<({integer},)>` is not implemented for `Option<_>`
```

Previous output:

```
error[E0425]: cannot find value `x` in this scope
 --> f10.rs:4:14
  |
4 |         Some(x * 2)
  |              ^ not found in this scope

error[E0277]: expected a `FnOnce<({integer},)>` closure, found `Option<_>`
 --> f10.rs:2:22
  |
2 |     let p = Some(45).and_then({
  |                      ^^^^^^^^ expected an `FnOnce<({integer},)>` closure, found `Option<_>`
  |
  = help: the trait `FnOnce<({integer},)>` is not implemented for `Option<_>`
```

Partially address #27300. Will require rebasing on top of #88546.
2021-09-16 22:17:33 +00:00
Aaron Hill
a41a13f775
Add ConstraintCategory::Usage for handling aggregate construction
In some cases, we emit borrowcheck diagnostics pointing
at a particular field expression in a struct expression
(e.g. `MyStruct { field: my_expr }`). However, this
behavior currently relies on us choosing the
`ConstraintCategory::Boring` with the 'correct' span.
When adding additional variants to `ConstraintCategory`,
(or changing existing usages away from `ConstraintCategory::Boring`),
the current behavior can easily get broken, since a non-boring
constraint will get chosen over a boring one.

To make the diagnostic output less fragile, this commit
adds a `ConstraintCategory::Usage` variant. We use this variant
for the temporary assignments created for each field of
an aggregate we are constructing.

Using this new variant, we can emit a message mentioning
"this usage", emphasizing the fact that the error message
is related to the specific use site (in the struct expression).

This is preparation for additional work on improving NLL error messages
(see #57374)
2021-09-16 12:36:19 -05:00
Esteban Kuber
8a3f712518 Refactor FulfillmentError to track less data
Move the information about pointing at the call argument expression in
an unmet obligation span from the `FulfillmentError` to a new
`ObligationCauseCode`.
2021-09-16 12:12:27 +00:00
jackh726
be76bdf905 Remove ToPredicate impls that use Binder::dummy 2021-09-15 20:54:50 -04:00
Will Crichton
47104a34a6 Allow call to get_body_with_borrowck_facts without -Z polonius 2021-09-15 11:45:31 -07:00
Tomasz Miąsko
b6b19f3b6c Use explicit log level in tracing instrument macro
Specify a log level in tracing instrument macro explicitly.

Additionally reduce the used log level from a default info level to a
debug level (all of those appear to be developer oriented logs, so there
should be no need to include them in release builds).
2021-09-15 19:02:10 +02:00
Fabian Wolff
21b7052eb8 Point to closure when emitting 'cannot move out' for captured variable 2021-09-15 01:47:22 +02:00
bors
d2dfb0eb8e Auto merge of #88811 - jackh726:issue-88446, r=nikomatsakis
Use a HashMap for UniverseInfo in mir borrowck

Fixes #88446

r? `@nikomatsakis`
2021-09-12 17:04:10 +00:00
bors
9ef27bf7dc Auto merge of #88771 - jackh726:wf_tys_set, r=nikomatsakis
Use FxHashSet instead of Vec for well formed tys

Trying to recover perf from #88312

r? `@ghost`
2021-09-12 10:32:55 +00:00
Matthias Krüger
c1e96085d3 don't clone types that are Copy (clippy::clone_on_copy) 2021-09-11 10:18:56 +02:00
jackh726
47035e4d08 Use FxHashMap 2021-09-09 23:28:20 -04:00
jackh726
0a3c6bb887 In relate_tys, when creating new universes, insert missing universes as other 2021-09-09 18:04:59 -04:00
Fabian Wolff
57fcb2e2d6 Fix two uses of span_note when the source is not available 2021-09-09 21:17:05 +02:00
jackh726
8e7613f9e0 Only add_implied_bounds for norm_ty if different 2021-09-09 11:26:16 -04:00
Robert Xiao
6ff5b471ef Fix issue #72649: avoid spurious "previous iteration of loop" errors.
Only follow backwards edges during get_moved_indexes if the move path is
definitely initialized at loop entry. Otherwise, the error occurred prior to the
loop, so we ignore the backwards edges to avoid generating misleading "value
moved here, in previous iteration of loop" errors.

This patch also slightly improves the analysis of inits, including
NonPanicPathOnly initializations (which are ignored by
drop_flag_effects::for_location_inits). This is required for the definite
initialization analysis, but may also help find certain skipped reinits in rare
cases.

Patch passes all non-ignored src/test/ui testcases.
2021-09-09 00:11:29 -06:00
Camille GILLOT
924dbc36c9 Rebase fallout. 2021-09-08 20:40:30 +02:00
Camille GILLOT
c5fc2609f0 Rename rustc_mir to rustc_const_eval. 2021-09-07 20:46:26 +02:00
Camille GILLOT
fd9c04fe32 Move the dataflow framework to its own crate. 2021-09-07 19:57:07 +02:00
Camille GILLOT
31a61ccc38 Move rustc_mir::borrow_check to new crate rustc_borrowck. 2021-09-07 00:29:22 +02:00