Commit Graph

2986 Commits

Author SHA1 Message Date
Yuki Okushi
97b9347c93
Rollup merge of #98083 - nnethercote:rename-Encoder, r=bjorn3
Rename rustc_serialize::opaque::Encoder as MemEncoder.

This avoids the name clash with `rustc_serialize::Encoder` (a trait),
and allows lots qualifiers to be removed and imports to be simplified
(e.g. fewer `as` imports).

(This was previously merged as commit 5 in #94732 and then was reverted
in #97905 because of a perf regression caused by commit 4 in #94732.)

r? ```@bjorn3```
2022-06-15 12:02:04 +09:00
Camille GILLOT
34e4d72929 Separate source_span and expn_that_defined from Definitions. 2022-06-14 22:45:51 +02:00
Camille GILLOT
603746a35e Make ResolverAstLowering a struct. 2022-06-14 22:44:27 +02:00
Camille GILLOT
47799de35a Separate Definitions and CrateStore from ResolverOutputs. 2022-06-14 22:44:27 +02:00
b-naber
15c1c06522 rebase 2022-06-14 17:57:51 +02:00
b-naber
060acc97db rebase 2022-06-14 16:12:28 +02:00
b-naber
773d8b2e15 address review 2022-06-14 16:11:27 +02:00
b-naber
dbef6e4507 address review 2022-06-14 16:08:18 +02:00
b-naber
5c95a3db2a fix clippy test failures 2022-06-14 16:08:11 +02:00
b-naber
705d818bd5 implement valtrees as the type-system representation for constant values 2022-06-14 16:07:11 +02:00
Nicholas Nethercote
abe45a9ffa Rename rustc_serialize::opaque::Encoder as MemEncoder.
This avoids the name clash with `rustc_serialize::Encoder` (a trait),
and allows lots qualifiers to be removed and imports to be simplified
(e.g. fewer `as` imports).

(This was previously merged as commit 5 in #94732 and then was reverted
in #97905 because of a perf regression caused by commit 4 in #94732.)
2022-06-14 14:52:01 +10:00
Nicholas Nethercote
93e4b6ef06 Rename the ConstS::val field as kind.
And likewise for the `Const::val` method.

Because its type is called `ConstKind`. Also `val` is a confusing name
because `ConstKind` is an enum with seven variants, one of which is
called `Value`. Also, this gives consistency with `TyS` and `PredicateS`
which have `kind` fields.

The commit also renames a few `Const` variables from `val` to `c`, to
avoid confusion with the `ConstKind::Value` variant.
2022-06-14 13:06:44 +10:00
Matthias Krüger
9d27f2e665
Rollup merge of #98043 - TaKO8Ki:remove-unnecessary-to-string, r=davidtwco
Remove unnecessary `to_string` and `String::new`

73fa217bc1 changed the type of the `suggestion` argument to `impl ToString`. This patch removes unnecessary `to_string` and `String::new`.

cc: `````@davidtwco`````
2022-06-13 21:35:56 +02:00
Matthias Krüger
e13eeedefc
Rollup merge of #97709 - compiler-errors:normalize-const-param-ty, r=oli-obk
Normalize consts' tys when relating with `adt_const_params`

Fixes #97007
2022-06-13 21:35:53 +02:00
Takayuki Maeda
77d6176e69 remove unnecessary to_string and String::new 2022-06-13 15:48:40 +09:00
Scott McMurray
a6c6fa0e33 Try out yeet in the MIR interpreter 2022-06-11 23:08:06 -07:00
Michael Goulet
5f7474e6dc Address comments 2022-06-11 16:38:48 -07:00
Michael Goulet
55805ab473 Make is_suggestable work on all TypeFoldable 2022-06-11 16:38:48 -07:00
Michael Goulet
9c47afe9fa Handle empty where-clause better 2022-06-11 16:27:01 -07:00
Michael Goulet
8506b7d4e0 Make Ty::is_suggestable use a visitor 2022-06-11 16:27:01 -07:00
Camille GILLOT
3039cfeb6a Make ExprKind::Closure a struct variant. 2022-06-12 00:16:27 +02:00
bors
99930ac7f8 Auto merge of #95880 - cjgillot:def-ident-span, r=petrochenkov
Handle `def_ident_span` like `def_span`.

`def_ident_span` had an ad-hoc status in the compiler.

This PR refactors it to be a first-class citizen like `def_span`:
- it gets encoded in the main metadata loop, instead of the visitor;
- its implementation is updated to mirror the one of `def_span`.

We do not remove the `Option` in the return type, since some items do not have an ident, AnonConsts for instance.
2022-06-11 20:08:48 +00:00
Dylan DPC
825d28057e
Rollup merge of #97913 - dingxiangfei2009:wrap-into-local-var-id, r=nikomatsakis
Wrap `HirId`s of locals into `LocalVarId`s for THIR nodes

This is the first effort to decouple `HirId`s from THIR. `HirId` is not very relevant in building THIR and MIR.

Based on the changeset, I think there are a few other pending refactoring that we could perform after this, in case we want to eliminate use of `HirId` in THIR.
- `TypeckResults::closure_min_captures` could be remapped from the variable `HirId`s to `LocalVarId` while the THIR is getting built.
- Use of `ScopeTree::var_scope` could be eliminated as well, since we will consider deprecating `ScopeTree` in the future.
2022-06-11 12:59:28 +02:00
bors
7092d42c04 Auto merge of #97980 - Dylan-DPC:rollup-l8exe4b, r=Dylan-DPC
Rollup of 6 pull requests

Successful merges:

 - #96868 (Stabilize explicit_generic_args_with_impl_trait)
 - #97703 (some additional `need_type_info.rs` cleanup)
 - #97812 (Suggest to swap a struct and a trait in trait impls)
 - #97958 (ExitStatus docs fixups)
 - #97967 (Mention `infer::Trace` methods on `infer::At` methods' docs)
 - #97972 (Update #[doc(html_playground_url)] documentation to mention what the request will be)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2022-06-11 06:17:54 +00:00
Dylan DPC
59c2ff532d
Rollup merge of #97703 - lcnr:post-89862, r=estebank
some additional `need_type_info.rs` cleanup

also fixes #97698, fixes #97806

cc `@estebank`
2022-06-11 07:42:13 +02:00
bors
c84594661c Auto merge of #97905 - nnethercote:revert-infallible-encoder, r=bjorn3
Revert part of #94372 to improve performance

#94732 was supposed to give small but widespread performance improvements, as judged from three per-merge performance runs. But the performance run that occurred after merging included a roughly equal number of improvements and regressions, for unclear reasons.

This PR is for a test run reverting those changes, to see what happens.

r? `@ghost`
2022-06-11 04:00:23 +00:00
Camille GILLOT
1a881a487b Introduce opt_ident. 2022-06-10 20:16:45 +02:00
Camille GILLOT
df59705301 Call def_span inside span_if_local. 2022-06-10 20:15:17 +02:00
Camille GILLOT
16f9f7c7b1 Implement def_ident_span in rustc_middle. 2022-06-10 20:15:14 +02:00
lcnr
54fac386a4 don't always cache bound lts 2022-06-10 10:09:50 +02:00
lcnr
543ca7d9e7 replace bound vars: make caching explicit 2022-06-10 10:09:50 +02:00
lcnr
8a0cb6ae7d BoundVarReplacer remove Option 2022-06-10 10:09:50 +02:00
Nicholas Nethercote
7f51a1b976 Revert b983e42936. 2022-06-10 08:35:03 +10:00
Ding Xiang Fei
6cad569a95
thir: wrap hir id of vars into local var id 2022-06-09 17:00:38 +08:00
bors
282445a288 Auto merge of #97740 - RalfJung:ctfe-cycle-spans, r=lcnr
use precise spans for recursive const evaluation

This fixes https://github.com/rust-lang/rust/issues/73283 by using a `TyCtxtAt` with a more precise span when the interpreter recursively calls itself. Hopefully such calls are sufficiently rare that this does not cost us too much performance.

(In theory, cycles can also arise through layout computation, as layout can depend on consts -- but layout computation happens all the time so we'd have to do something to not make this terrible for performance.)
2022-06-09 01:52:15 +00:00
Gary Guo
14d155a3dc Rename panic_strategy query to required_panic_strategy 2022-06-08 21:32:41 +01:00
Gary Guo
6ef2033884 Fix FFI-unwind unsoundness with mixed panic mode 2022-06-08 21:32:41 +01:00
bors
1a97162cb2 Auto merge of #94732 - nnethercote:infallible-encoder, r=bjorn3
Make `Encodable` and `Encoder` infallible.

A follow-up to #93066.

r? `@ghost`
2022-06-08 10:24:12 +00:00
lcnr
b7ab4777b2 note that methods should only be used for diags 2022-06-08 10:13:02 +02:00
lcnr
2ea468e386 dedup diagnostics default params handling 2022-06-08 10:13:00 +02:00
lcnr
154eba64b9 publicly export ty::subst in ty
it feels arbitrary to have `Ty` and `Const` directly
in that module and to not have `GenericArg` and
`GenericArgKind` there. Writing `ty::GenericArg`
can also feel clearer than importing it. Using
`ty::subst::GenericArg` however is ugly.
2022-06-08 10:11:29 +02:00
bors
e45d9973b2 Auto merge of #97860 - Dylan-DPC:rollup-t3vxos8, r=Dylan-DPC
Rollup of 5 pull requests

Successful merges:

 - #97595 (Remove unwrap from get_vtable)
 - #97597 (Preserve unused pointer to address casts)
 - #97819 (Recover `import` instead of `use` in item)
 - #97823 (Recover missing comma after match arm)
 - #97851 (Use repr(C) when depending on struct layout in ptr tests)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2022-06-08 08:05:47 +00:00
Dylan DPC
d380b457d8
Rollup merge of #97597 - tmiasko:simplify-locals-side-effects, r=RalfJung,JakobDegen
Preserve unused pointer to address casts

Fixes #97421.

cc `@RalfJung`
2022-06-08 07:37:30 +02:00
bors
64a7aa7016 Auto merge of #97447 - nnethercote:improve-folding, r=jackh726
Folding revamp

r? `@ghost`
2022-06-08 05:36:40 +00:00
Nicholas Nethercote
b983e42936 Rename rustc_serialize::opaque::Encoder as MemEncoder.
This avoids the name clash with `rustc_serialize::Encoder` (a trait),
and allows lots qualifiers to be removed and imports to be simplified
(e.g. fewer `as` imports).
2022-06-08 09:50:44 +10:00
Nicholas Nethercote
90db033955 Folding revamp.
This commit makes type folding more like the way chalk does it.

Currently, `TypeFoldable` has `fold_with` and `super_fold_with` methods.
- `fold_with` is the standard entry point, and defaults to calling
  `super_fold_with`.
- `super_fold_with` does the actual work of traversing a type.
- For a few types of interest (`Ty`, `Region`, etc.) `fold_with` instead
  calls into a `TypeFolder`, which can then call back into
  `super_fold_with`.

With the new approach, `TypeFoldable` has `fold_with` and
`TypeSuperFoldable` has `super_fold_with`.
- `fold_with` is still the standard entry point, *and* it does the
  actual work of traversing a type, for all types except types of
  interest.
- `super_fold_with` is only implemented for the types of interest.

Benefits of the new model.
- I find it easier to understand. The distinction between types of
  interest and other types is clearer, and `super_fold_with` doesn't
  exist for most types.
- With the current model is easy to get confused and implement a
  `super_fold_with` method that should be left defaulted. (Some of the
  precursor commits fixed such cases.)
- With the current model it's easy to call `super_fold_with` within
  `TypeFolder` impls where `fold_with` should be called. The new
  approach makes this mistake impossible, and this commit fixes a number
  of such cases.
- It's potentially faster, because it avoids the `fold_with` ->
  `super_fold_with` call in all cases except types of interest. A lot of
  the time the compile would inline those away, but not necessarily
  always.
2022-06-08 09:24:03 +10:00
Nicholas Nethercote
23880a058b Add try_fold_uenevaluted.
We already have `visit_unevaluated`, so this improves consistency.

Also, define `TypeFoldable for Unevaluated<'tcx, ()>` in terms of
`TypeFoldable for Unevaluated<'tcx>`, which is neater.
2022-06-08 09:22:23 +10:00
Nicholas Nethercote
6ba2dfd330 Add TypeVisitor::visit_mir_const.
Because `TypeFoldable::try_fold_mir_const` exists, and even though
`visit_mir_const` isn't needed right now, the consistency makes the code
easier to understand.
2022-06-08 09:22:23 +10:00
Nicholas Nethercote
ca7585ab9a Remove EarlyBinder::{try_fold_with,visit_with}.
For most types the default impls of these methods are good enough, and
`EarlyBinder` is one such type.
2022-06-08 09:22:23 +10:00
Nicholas Nethercote
28be201d2f Use super_visit_with in a couple of visit_binder methods.
Because it's equivalent but simpler to what's currently there.
2022-06-08 09:22:23 +10:00
Nicholas Nethercote
465d198c74 Rename TypeVisitor::visit_unevaluated_const.
To match the corresponding type name.
2022-06-08 09:22:23 +10:00
Nicholas Nethercote
1acbe7573d Use delayed error handling for Encodable and Encoder infallible.
There are two impls of the `Encoder` trait: `opaque::Encoder` and
`opaque::FileEncoder`. The former encodes into memory and is infallible, the
latter writes to file and is fallible.

Currently, standard `Result`/`?`/`unwrap` error handling is used, but this is a
bit verbose and has non-trivial cost, which is annoying given how rare failures
are (especially in the infallible `opaque::Encoder` case).

This commit changes how `Encoder` fallibility is handled. All the `emit_*`
methods are now infallible. `opaque::Encoder` requires no great changes for
this. `opaque::FileEncoder` now implements a delayed error handling strategy.
If a failure occurs, it records this via the `res` field, and all subsequent
encoding operations are skipped if `res` indicates an error has occurred. Once
encoding is complete, the new `finish` method is called, which returns a
`Result`. In other words, there is now a single `Result`-producing method
instead of many of them.

This has very little effect on how any file errors are reported if
`opaque::FileEncoder` has any failures.

Much of this commit is boring mechanical changes, removing `Result` return
values and `?` or `unwrap` from expressions. The more interesting parts are as
follows.
- serialize.rs: The `Encoder` trait gains an `Ok` associated type. The
  `into_inner` method is changed into `finish`, which returns
  `Result<Vec<u8>, !>`.
- opaque.rs: The `FileEncoder` adopts the delayed error handling
  strategy. Its `Ok` type is a `usize`, returning the number of bytes
  written, replacing previous uses of `FileEncoder::position`.
- Various methods that take an encoder now consume it, rather than being
  passed a mutable reference, e.g. `serialize_query_result_cache`.
2022-06-08 07:01:26 +10:00
Tomasz Miąsko
6277c3a944 Preserve unused pointer to address casts 2022-06-07 17:33:16 +02:00
Dylan DPC
fd76e0eee0
Rollup merge of #97325 - tmiasko:capture-enum-field, r=arora-aman
Fix precise field capture of univariant enums

When constructing a MIR from a THIR field expression, introduce an
additional downcast projection before accessing a field of an enum.

When rebasing a place builder on top of a captured place, account for
the fact that a single HIR enum field projection corresponds to two MIR
projection elements: a downcast element and a field element.

Fixes #95271.
Fixes #96299.
Fixes #96512.
Fixes #97378.

r? ``@nikomatsakis`` ``@arora-aman``
2022-06-07 17:25:43 +02:00
bors
7fe2c4b00d Auto merge of #97825 - Dylan-DPC:rollup-ya51k1k, r=Dylan-DPC
Rollup of 5 pull requests

Successful merges:

 - #97058 (Various refactors to the incr comp workproduct handling)
 - #97301 (Allow unstable items to be re-exported unstably without requiring the feature be enabled)
 - #97738 (Fix ICEs from zsts within unsized types with non-zero offsets)
 - #97771 (Remove SIGIO reference on Haiku)
 - #97808 (Add some unstable target features for the wasm target codegen)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2022-06-07 11:08:58 +00:00
Dylan DPC
2035b50d80
Rollup merge of #97301 - semicoleon:unstable-reexport, r=petrochenkov
Allow unstable items to be re-exported unstably without requiring the feature be enabled

Closes #94972

The diagnostic may need some work still, and I haven't added a test yet
2022-06-07 11:41:07 +02:00
Dylan DPC
ab1027ad0f
Rollup merge of #97058 - bjorn3:multi_artifact_work_products, r=nagisa
Various refactors to the incr comp workproduct handling

This is the result of me looking into adding support for having multiple object files for a single codegen unit to incr comp. This is necessary to support inline assembly in cg_clif without requiring partial linking which is not supported on Windows and seems to fail on macOS for some reason. Cg_clif uses an external assembler to handle inline asm and thus produces one object file with regular functions and one object file containing compiled inline asm for each codegen unit which uses inline asm. Current incr comp can't handle this. This PR doesn't yet add support for this, but it makes it easier to do so.
2022-06-07 11:41:06 +02:00
bors
91cacb3faf Auto merge of #97512 - scottmcm:add-coldcc, r=nagisa,lcnr
Add support for emitting functions with `coldcc` to LLVM

The eventual goal is to try using this for things like the internal panicking stuff, to see whether it helps.
2022-06-07 08:12:45 +00:00
bors
bb55bd449e 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
bors
357bc27904 Auto merge of #97795 - Dylan-DPC:rollup-dxilagr, r=Dylan-DPC
Rollup of 5 pull requests

Successful merges:

 - #97312 (Compute lifetimes in scope at diagnostic time)
 - #97495 (Add E0788 for improper #[no_coverage] usage)
 - #97579 (Avoid creating `SmallVec`s in `global_llvm_features`)
 - #97767 (interpret: do not claim UB until we looked more into variadic functions)
 - #97787 (E0432: rust 2018 -> rust 2018 or later    in --explain message)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2022-06-06 16:09:54 +00:00
bors
9d20fd1098 Auto merge of #97684 - RalfJung:better-provenance-control, r=oli-obk
interpret: better control over whether we read data with provenance

The resolution in https://github.com/rust-lang/unsafe-code-guidelines/issues/286 seems to be that when we load data at integer type, we implicitly strip provenance. So let's implement that in Miri at least for scalar loads. This makes use of the fact that `Scalar` layouts distinguish pointer-sized integers and pointers -- so I was expecting some wild bugs where layouts set this incorrectly, but so far that does not seem to happen.

This does not entirely implement the solution to https://github.com/rust-lang/unsafe-code-guidelines/issues/286; we still do the wrong thing for integers in larger types: we will `copy_op` them and then do validation, and validation will complain about the provenance. To fix that we need mutating validation; validation needs to strip the provenance rather than complaining about it. This is a larger undertaking (but will also help resolve https://github.com/rust-lang/miri/issues/845 since we can reset padding to `Uninit`).

The reason this is useful is that we can now implement `addr` as a `transmute` from a pointer to an integer, and actually get the desired behavior of stripping provenance without exposing it!
2022-06-06 13:28:58 +00:00
Dylan DPC
a736acc804
Rollup merge of #97312 - cjgillot:no-path-in-scope, r=compiler-errors
Compute lifetimes in scope at diagnostic time

The set of available lifetimes is currently computed during lifetime resolution on HIR.  It is only used for one diagnostic.

In this PR, HIR lifetime resolution just reports whether elided lifetimes are well-defined at the place of use.  The diagnostic code is responsible for building a list of lifetime names if elision is not allowed.

This will allow to remove lifetime resolution on HIR eventually.
2022-06-06 14:34:55 +02:00
bjorn3
02162c4163 Rename CodegenUnit::work_product to previous_work_product
It returns the previous work product or panics if there is none. This rename
makes the purpose of this method clearer.
2022-06-06 12:30:10 +00:00
Michael Goulet
c1f4f980f4 Do wfcheck on ADT field before Sized check 2022-06-05 23:05:14 -07:00
Ralf Jung
47d11a8483 interpret: better control over whether we read data with provenance, and implicit provenance stripping where possible 2022-06-05 10:13:34 -04:00
bors
4322a785cc Auto merge of #97697 - WaffleLapkin:no_ref_vec, r=WaffleLapkin
Replace `&Vec<_>`s with `&[_]`s

It's generally preferable to use `&[_]` since it's one less indirection and it can be created from types other that `Vec`.

I've left `&Vec` in some locals where it doesn't really matter, in cases where `TypeFoldable` is expected (`TypeFoldable: Clone` so slice can't implement it) and in cases where it's `&TypeAliasThatIsActiallyVec`. Nothing important, really, I was just a little annoyed by `visit_generic_param_vec` :D

r? `@compiler-errors`
2022-06-05 09:30:53 +00:00
cole
f3d93b6c62 Allow unstable items to be re-exported unstably without requiring the feature be enabled 2022-06-04 17:05:33 -05:00
Matthias Krüger
1794309e0a
Rollup merge of #97737 - jackh726:verbose-pretty-printing-fix, r=compiler-errors
Fix pretty printing named bound regions under -Zverbose

Fixed regression introduced in #97023

r? `@compiler-errors`

cc `@cjgillot`
2022-06-04 23:42:04 +02:00
Matthias Krüger
326315bf54
Rollup merge of #97609 - Elliot-Roberts:unused-trait-refactor, r=cjgillot
Iterate over `maybe_unused_trait_imports` when checking dead trait imports

Closes #96873
r? `@cjgillot`

Some questions, if you have time:

- Is there a way to shorten the `rustc_data_structures::fx::FxIndexSet` path in the query declaration? I wasn't sure where to put a `use`.
- Was returning by reference from the query the right choice here?
- How would I go about evaluating the importance of the `is_dummy()` call in `check_crate`? I don't see failing tests when I comment it out. Should I just try to determine whether dummy spans can ever be put into `maybe_unused_trait_imports`?
- Am I doing anything silly with the various ID types?
- Is that `let-else` with `unreachable!()` bad? (i.e is there a better idiom? Would `panic!("<explanation>")` be better?)
- If I want to evaluate the perf of using a `Vec` as mentioned in #96873, is the best way to use the CI or is it feasible locally?

Thanks :)
2022-06-04 23:42:00 +02:00
Jack Huey
dd38fecb78 Fix pretty printing named bound regions under -Zverbose 2022-06-04 17:32:27 -04:00
Ralf Jung
467e0f4446 use precise spans for recursive const evaluation 2022-06-04 16:18:03 -04:00
Elliot Roberts
76c6845a85 Iterate over maybe_unused_trait_imports when checking dead trait imports 2022-06-04 12:38:55 -07:00
Camille GILLOT
af8739b96e Completely remove LifetimeScopeForPath. 2022-06-04 15:33:27 +02:00
Camille GILLOT
a07290047e Compute lifetimes in scope at diagnostic time. 2022-06-04 15:28:15 +02:00
Jack Huey
410dcc9674 Fully stabilize NLL 2022-06-03 17:16:41 -04:00
Camille GILLOT
623ea5f5d2 Make hir().get_generics and generics_of consistent. 2022-06-03 23:07:04 +02:00
Michael Goulet
27af8e4585 Normalize consts' tys when relating with adt_const_params 2022-06-03 13:14:23 -07:00
bors
7e9b92cb43 Auto merge of #85993 - bjorn3:serde_json, r=wesleywiser
Remove all json handling from rustc_serialize

Json is now handled using serde_json. Where appropriate I have replaced json usage with binary serialization (rmeta files) or manual string formatting (emcc linker arg generation).

This allowed for removing and simplifying a lot of code, which hopefully results in faster serialization/deserialization and faster compiles of rustc itself.

Where sensible we now use serde. Metadata and incr cache serialization keeps using a heavily modified (compared to crates.io) rustc-serialize version that in the future could probably be extended with zero-copy deserialization or other perf tricks that serde can't support due to supporting more than one serialization format.

Note that I had to remove `-Zast-json` and `-Zast-json-noexpand` as the relevant AST types don't implement `serde::Serialize`.

Fixes #40177

See also https://github.com/rust-lang/compiler-team/issues/418
2022-06-03 17:55:02 +00:00
bjorn3
7381ea019c Remove emit_unit
It doesn't do anything for all encoders
2022-06-03 17:02:14 +00:00
bjorn3
fc1df4ff17 Use serde_json for target spec json 2022-06-03 16:46:19 +00:00
Maybe Waffle
afaa9854fa Replace &Vec<_>s with &[_]s 2022-06-03 20:42:42 +04:00
bors
9a74608543 Auto merge of #97694 - Dylan-DPC:rollup-2yxo7ce, r=Dylan-DPC
Rollup of 3 pull requests

Successful merges:

 - #97415 (Compute `is_late_bound_map` query separately from lifetime resolution)
 - #97471 (Provide more context when denying invalid type params )
 - #97681 (Add more eslint checks)

Failed merges:

 - #97446 (Make hir().get_generics and generics_of consistent.)

r? `@ghost`
`@rustbot` modify labels: rollup
2022-06-03 15:26:06 +00:00
Dylan DPC
53ab3b2e6e
Rollup merge of #97415 - cjgillot:is-late-bound-solo, r=estebank
Compute `is_late_bound_map` query separately from lifetime resolution

This query is actually very simple, and is only useful for functions and method.  It can be computed directly by fetching the HIR, with no need to embed it within the lifetime resolution visitor.

Based on https://github.com/rust-lang/rust/pull/96296
2022-06-03 17:10:51 +02:00
bors
e40d5e83dc Auto merge of #89862 - lcnr:path-generics-diagnostics, r=estebank
rewrite error handling for unresolved inference vars

Pretty much completely rewrites `fn emit_inference_failure_err`.

This new setup should hopefully be easier to extend and is already a lot better when looking for generic arguments.
Because this is a rewrite there are still some parts which are lacking, these are tracked in #94483 and will be fixed in later PRs.

r? `@estebank` `@petrochenkov`
2022-06-03 12:37:16 +00:00
Camille GILLOT
ba40fe99c3 Compute is_late_bound in a separate query.
The computation is actually much simpler, and can be done by directly
fetching the HIR for the `FnDecl` and its generics.
2022-06-03 12:05:04 +02:00
Camille GILLOT
b1294e86bb Manipulate lifetimes by LocalDefId for region resolution. 2022-06-03 12:03:20 +02:00
Dylan DPC
b71ddd6861
Rollup merge of #97664 - estebank:suggest-bound-derive-copy, r=compiler-errors
On E0204 suggest missing type param bounds

```
error[E0204]: the trait `Copy` may not be implemented for this type
  --> f42.rs:9:17
   |
9  | #[derive(Debug, Copy, Clone)]
   |                 ^^^^
10 | pub struct AABB<K>{
11 |     pub loc: Vector2<K>,
   |     ------------------- this field does not implement `Copy`
12 |     pub size: Vector2<K>
   |     -------------------- this field does not implement `Copy`
   |
note: the `Copy` impl for `Vector2<K>` requires that `K: Debug`
  --> f42.rs:11:5
   |
11 |     pub loc: Vector2<K>,
   |     ^^^^^^^^^^^^^^^^^^^
note: the `Copy` impl for `Vector2<K>` requires that `K: Debug`
  --> f42.rs:12:5
   |
12 |     pub size: Vector2<K>
   |     ^^^^^^^^^^^^^^^^^^^^
   = note: this error originates in the derive macro `Copy` (in Nightly builds, run with -Z macro-backtrace for more info)
help: consider restricting type parameter `K`
   |
10 | pub struct AABB<K: Debug>{
   |                  +++++++
```

Fix #89137.
2022-06-03 11:18:26 +02:00
Dylan DPC
f116dd76ed
Rollup merge of #97653 - RalfJung:int-to-ptr, r=oli-obk
add cast kind of from_exposed_addr (int-to-ptr casts)

This is basically the dual to https://github.com/rust-lang/rust/pull/97582, for int2ptr casts.

Cc `@tmiasko` https://github.com/rust-lang/rust/issues/97649
2022-06-03 11:18:24 +02:00
Esteban Küber
8567b686f9 On E0204 suggest missing type param bounds
```
error[E0204]: the trait `Copy` may not be implemented for this type
  --> f42.rs:9:17
   |
9  | #[derive(Debug, Copy, Clone)]
   |                 ^^^^
10 | pub struct AABB<K>{
11 |     pub loc: Vector2<K>,
   |     ------------------- this field does not implement `Copy`
12 |     pub size: Vector2<K>
   |     -------------------- this field does not implement `Copy`
   |
note: the `Copy` impl for `Vector2<K>` requires that `K: Debug`
  --> f42.rs:11:5
   |
11 |     pub loc: Vector2<K>,
   |     ^^^^^^^^^^^^^^^^^^^
note: the `Copy` impl for `Vector2<K>` requires that `K: Debug`
  --> f42.rs:12:5
   |
12 |     pub size: Vector2<K>
   |     ^^^^^^^^^^^^^^^^^^^^
   = note: this error originates in the derive macro `Copy` (in Nightly builds, run with -Z macro-backtrace for more info)
help: consider restricting type parameter `K`
   |
10 | pub struct AABB<K: Debug>{
   |                  +++++++
```

Fix #89137.
2022-06-02 12:54:04 -07:00
Ralf Jung
fafccdced3 add cast kind of from_exposed_addr (int-to-ptr casts) 2022-06-02 10:46:13 -04:00
Dylan DPC
5c041f98fa
Rollup merge of #97023 - cjgillot:uniform-anon, r=estebank
Diagnose anonymous lifetimes errors more uniformly between async and regular fns

Async fns and regular fns are desugared differently.  For the former, we create a generic parameter at HIR level.  For the latter, we just create an anonymous region for typeck.

I plan to migrate regular fns to the async fn desugaring.

Before that, this PR attempts to merge the diagnostics for both cases.

r? ```@estebank```
2022-06-02 11:13:22 +02:00
lcnr
3fe346e7a3 add new emit_inference_failure_err 2022-06-02 10:19:15 +02:00
Ralf Jung
4dc5d457d8 rename PointerAddress → PointerExposeAddress 2022-06-01 14:08:17 -04:00
Tomasz Miąsko
dff602fc18 Add a pointer to address cast kind
A pointer to address cast are often special-cased.
Introduce a dedicated cast kind to make them easy distinguishable.
2022-05-31 00:00:00 +00:00
bors
c35035cefc Auto merge of #97025 - ouz-a:mini-derefer-generator, r=davidtwco
Add validation layer for Derefer

_Follow up work to #96549 #96116 #95857 #95649_

This adds validation for Derefer making sure it is always the first projection.

r? rust-lang/mir-opt
2022-05-30 20:06:25 +00:00
ouz-a
e71913e847 validate derefer, run derefer inside generator 2022-05-30 18:36:14 +03:00
bors
5c780b98d1 Auto merge of #96964 - oli-obk:const_trait_mvp, r=compiler-errors
Replace `#[default_method_body_is_const]` with `#[const_trait]`

pulled out of #96077

related issues:  #67792 and #92158

cc `@fee1-dead`

This is groundwork to only allowing `impl const Trait` for traits that are marked with `#[const_trait]`. This is necessary to prevent adding a new default method from becoming a breaking change (as it could be a non-const fn).
2022-05-30 09:19:03 +00:00
Oli Scherer
4d390de4a3 Add a helper function for checking whether a default function in a trait can be treated as const 2022-05-30 08:52:25 +00:00
Deadbeef
257f06587c Remove #[default..] and add #[const_trait] 2022-05-30 08:52:24 +00:00
Scott McMurray
e90be842fb Add support for emitting functions with coldcc in LLVM
The eventual goal is to try using this for things like the internal panicking stuff, to see whether it helps.
2022-05-30 00:19:23 -07:00
bors
bef2b7cd1c Auto merge of #97214 - Mark-Simulacrum:stage0-bump, r=pietroalbini
Finish bumping stage0

It looks like the last time had left some remaining cfg's -- which made me think
that the stage0 bump was actually successful. This brings us to a released 1.62
beta though.

This now brings us to cfg-clean, with the exception of check-cfg-features in bootstrap;
I'd prefer to leave that for a separate PR at this time since it's likely to be more tricky.

cc https://github.com/rust-lang/rust/pull/97147#issuecomment-1132845061

r? `@pietroalbini`
2022-05-29 16:28:21 +00:00
Camille GILLOT
8da27078d3 Stop pretty-printing anonymous lifetimes. 2022-05-29 12:16:09 +02:00
bors
0f06824013 Auto merge of #97287 - compiler-errors:type-interner, r=jackh726,oli-obk
Move things to `rustc_type_ir`

Finishes some work proposed in https://github.com/rust-lang/compiler-team/issues/341.

r? `@ghost`
2022-05-29 08:20:13 +00:00
bors
14f477e78a Auto merge of #97472 - cuviper:rebase-rustc-rayon, r=Mark-Simulacrum
Update to rebased rustc-rayon 0.4

In rayon-rs/rayon#938, miri uncovered a race in `rustc-rayon-core` that had already been fixed in the regular `rayon-core`. I have now rebased that fork onto the latest rayon branch, and published as 0.4. I also updated `indexmap` to bump the dependency.

`Cargo.lock` changes:

    Updating indexmap v1.8.0 -> v1.8.2
    Updating rayon v1.5.1 -> v1.5.3
    Updating rayon-core v1.9.1 -> v1.9.3
    Updating rustc-rayon v0.3.2 -> v0.4.0
    Updating rustc-rayon-core v0.3.2 -> v0.4.1
2022-05-28 22:24:53 +00:00
Michael Goulet
4638915940 Make TyCtxt implement Interner, make HashStable generic and move to rustc_type_ir 2022-05-28 12:16:05 -07:00
Michael Goulet
f05a92d158 Remove some comments, inline interner fn 2022-05-28 11:38:22 -07:00
Michael Goulet
34e05812e0 Fix TyKind lint, make consts no longer fn, etc 2022-05-28 11:38:22 -07:00
Michael Goulet
a056a953f0 Initial fixes on top of type interner commit 2022-05-28 11:38:22 -07:00
Wilco Kusee
a7015fe816 Move things to rustc_type_ir 2022-05-28 11:38:22 -07:00
bors
4f39fb1f34 Auto merge of #97383 - dingxiangfei2009:restore-region-scope-tree-query, r=dingxiangfei2009
Try to cache region_scope_tree as a query

This PR will attempt to restore `region_scope_tree` as a query so that caching works again. It seems that `region_scope_tree` could be re-computed for nested items after all, which could explain the performance regression introduced by #95563.

cc `@Mark-Simulacrum` `@pnkfelix` I will try to trigger a perf run here.
2022-05-28 14:30:25 +00:00
bors
68314177e7 Auto merge of #97158 - JakobDegen:dse, r=tmiasko,cjgillot
Split dead store elimination off dest prop

This splits off a part of #96451 . I've added this in as its own pass for now, so that it actually runs, can be tested, etc. In the dest prop PR, I'll stop invoking this as its own pass, so that it doesn't get invoked twice.

r? `@tmiasko`
2022-05-28 11:49:42 +00:00
bors
ed76b773b5 Auto merge of #97284 - b-naber:constraint-dyn-impl-suggestion, r=estebank
Add suggestion for relaxing static lifetime bounds on dyn trait impls in NLL

This PR introduces suggestions for relaxing static lifetime bounds on impls of dyn trait items for NLL similar to what is already available in lexical region diagnostics.

Fixes https://github.com/rust-lang/rust/issues/95701

r? `@estebank`
2022-05-28 04:04:29 +00:00
Josh Stone
ab57e36268 Update to rebased rustc-rayon 0.4 2022-05-27 20:20:41 -07:00
Matthias Krüger
e96397b63f
Rollup merge of #97453 - lcnr:comment, r=jackh726
rename `TyKind` to `RegionKind` in comment in rustc_middle
2022-05-28 01:11:48 +02:00
lcnr
4781246a2c fix comment 2022-05-27 16:36:59 +02:00
Mark Rousskov
b454991ac4 Finish bumping stage0
It looks like the last time had left some remaining cfg's -- which made me think
that the stage0 bump was actually successful. This brings us to a released 1.62
beta though.
2022-05-27 07:36:17 -04:00
bors
56fd680cf9 Auto merge of #96046 - oli-obk:const_typeck, r=cjgillot
Move various checks to typeck so them failing causes the typeck result to get tainted

Fixes #69487
fixes #79047

cc `@RalfJung` this gets rid of the `Transmute` invalid program error variant
2022-05-27 11:31:37 +00:00
Matthias Krüger
5fc8a8e227 clippy::complexity fixes
clone_on_copy
useless_format
bind_instead_of_map
filter_map_identity
useless_conversion
map_flatten
unnecessary_unwrap
2022-05-26 13:14:24 +02:00
b-naber
3c6c8d5a8d rebase, use Ty in CallArgument and re-insert static_assert_size on ConstraintCategory 2022-05-26 10:11:58 +02:00
b-naber
99fa572ab1 add def_id and substs to ConstraintCategory::CallArgument 2022-05-25 18:13:03 +02:00
bors
4a99c5f504 Auto merge of #97345 - lcnr:fast_reject, r=nnethercote
add a deep fast_reject routine

continues the work on #97136.

r? `@nnethercote`

Actually agree with you on the match structure 😆 let's see how that impacted perf 😅
2022-05-25 08:36:46 +00:00
Ding Xiang Fei
4c6074fbb0
try to cache region_scope_tree as a query 2022-05-25 13:52:32 +08:00
lcnr
a76277c6c4 add a deep fast_reject routine 2022-05-25 07:40:38 +02:00
Jakob Degen
bf153a241d Add dead store elimination pass 2022-05-24 22:50:21 -04:00
Michael Goulet
d1a9a95517 Make Lazy not care about lifetimes until decode 2022-05-24 15:54:44 -07:00
Oli Scherer
0d88631059 Add the transmute and asm checks to typeck as deferred checks 2022-05-24 16:28:57 +00:00
Oli Scherer
0fdaaadb36 Remove the check_mod_intrinsics query 2022-05-24 15:46:23 +00:00
Jakob Degen
09b0936db2 Refactor call terminator to always hold a destination place 2022-05-23 17:49:04 -04:00
Tomasz Miąsko
0e7eca77e1 Fix precise field capture of univariant enums
When constructing a MIR from a THIR field expression, introduce an
additional downcast projection before accessing a field of an enum.

When rebasing a place builder on top of a captured place, account for
the fact that a single HIR enum field projection corresponds to two MIR
projection elements: a downcast element and a field element.
2022-05-23 19:07:06 +02:00
Dylan DPC
f4bf64c3f0
Rollup merge of #97292 - compiler-errors:tcxify-rustc, r=davidtwco
Lifetime variance fixes for rustc

#97287 migrates rustc to a `Ty` type that is invariant over its lifetime `'tcx`, so I need to fix a bunch of places that assume that `Ty<'a>` and `Ty<'b>` can be unified by shortening both to some common lifetime.

This is doable, since many lifetimes are already `'tcx`, so all this PR does is be a bit more explicit that elided lifetimes are actually `'tcx`.

Split out from #97287 so the compiler team can review independently.
2022-05-23 15:11:04 +02:00
Michael Goulet
1784634a39 Lifetime variance fixes for rustc 2022-05-22 14:29:32 -07:00
Jack Huey
683a9c8391 Do leak check after function ptr coercion 2022-05-22 11:18:36 -04:00
bors
653463731a Auto merge of #95563 - dingxiangfei2009:dxf-rfc66-refactor, r=nikomatsakis
Move the extended lifetime resolution into typeck context

Related to #15023

This PR is based on the [idea](https://github.com/rust-lang/rust/issues/15023#issuecomment-1070931433) of #15023 by `@nikomatsakis.`

This PR specifically proposes to
- Delay the resolution of scopes of rvalues to a later stage, so that enough type information is available to refine those scopes based on relationships of lifetimes.
- Highlight relevant parts that would help future reviews on the next installments of works to fully implement a solution to RFC 66.
2022-05-22 09:00:30 +00:00
Ding Xiang Fei
6044fbe462
factor out the rvalue lifetime rule
remove region_scope_tree from RegionCtxt

Apply suggestions from code review

Co-authored-by: Niko Matsakis <niko@alum.mit.edu>
2022-05-22 16:46:50 +08:00
bors
acfd327fd4 Auto merge of #97177 - oli-obk:const-stability, r=davidtwco
Implement proper stability check for const impl Trait, fall back to unstable const when undeclared

Continuation of #93960

`@jhpratt` it looks to me like the test was simply not testing for the failure you were looking for? Your checks actually do the right thing for const traits?
2022-05-22 06:47:36 +00:00
Yuki Okushi
97e1ab0005
Rollup merge of #97259 - jyn514:fix-typo, r=JohnTitor
Fix typo in Mir phase docs
2022-05-22 11:53:09 +09:00
bors
e52e7115c7 Auto merge of #96515 - lcnr:user-types-in-pat, r=nikomatsakis
correctly deal with user type ascriptions in pat

supersedes #93856

`thir::PatKind::AscribeUserType` previously resulted in `CanonicalUserTypeAnnotations` where the inferred type already had a subtyping relation according to `variance` to the `user_ty`.

The bug can pretty much be summarized as follows:

- during mir building
  - `user_ty -> inferred_ty`: considers variance
  - `StatementKind::AscribeUserType`: `inferred_ty` is the type of the place, so no variance needed
- during mir borrowck
  - `user_ty -> inferred_ty`: does not consider variance
  - `StatementKind::AscribeUserType`: applies variance

This mostly worked fine. The lifetimes in `inferred_ty` were only bound by its relation to `user_ty` and to the `place` of `StatementKind::AscribeUserType`, so it doesn't matter where exactly the subtyping happens.

It does however matter when having higher ranked subtying. At this point the place where the subtyping happens is forced, causing this mismatch between building and borrowck to result in unintended errors.

cc #96514 which is pretty much the same issue

r? `@nikomatsakis`
2022-05-21 23:34:30 +00:00
Joshua Nelson
0c92d1c7f3 Fix typo in Mir phase docs 2022-05-21 16:21:44 -05:00
bors
4f372b14de Auto merge of #97239 - jhpratt:remove-crate-vis, r=joshtriplett
Remove `crate` visibility modifier

FCP to remove this syntax is just about complete in #53120. Once it completes, this should be merged ASAP to avoid merge conflicts.

The first two commits remove usage of the feature in this repository, while the last removes the feature itself.
2022-05-21 06:38:49 +00:00
lcnr
db11c1939c update mir user type printing and apparently fix an ICE 2022-05-21 08:13:17 +02:00
lcnr
39a03779f8 correctly deal with user type ascriptions in pat 2022-05-21 08:13:17 +02:00
Jacob Pratt
49c82f31a8
Remove crate visibility usage in compiler 2022-05-20 20:04:54 -04:00
bors
e6a4afc3af Auto merge of #95418 - cjgillot:more-disk, r=davidtwco
Cache more queries on disk

One of the principles of incremental compilation is to allow saving results on disk to avoid recomputing them.
This PR investigates persisting a lot of queries whose result are to be saved into metadata.
Some of the queries are cheap reads from HIR, but we may also want to get rid of these reads for incremental lowering.
2022-05-20 20:49:55 +00:00
bors
22ee39504a Auto merge of #97211 - GuillaumeGomez:rollup-jul7x7e, r=GuillaumeGomez
Rollup of 6 pull requests

Successful merges:

 - #96565 (rustdoc: show implementations on `#[fundamental]` wrappers)
 - #97179 (Add new lint to enforce whitespace after keywords)
 - #97185 (interpret/validity: separately control checking numbers for being init and non-ptr)
 - #97188 (Remove unneeded null pointer asserts in ptr2int casts)
 - #97189 (Update .mailmap)
 - #97192 (Say "last" instead of "rightmost" in the documentation for `std::str:rfind`)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2022-05-20 13:18:37 +00:00
Guillaume Gomez
706aa59efa
Rollup merge of #97185 - RalfJung:number-validity, r=oli-obk
interpret/validity: separately control checking numbers for being init and non-ptr

This lets Miri control this in a more fine-grained way.

r? `@oli-obk`
2022-05-20 14:03:03 +02:00
lcnr
4a82bc9ea0 bool to custom enum 2022-05-20 11:50:07 +02:00
lcnr
f3f68324cc move unique param check into rustc_middle 2022-05-20 11:27:06 +02:00
Ralf Jung
5514b1176f interpret/validity: separately control checking numbers for being init and non-ptr 2022-05-19 20:16:25 +02:00
bors
c067287049 Auto merge of #97024 - lcnr:simplify_type-sus, r=<try>
`simplify_type` improvements and cursed docs

the existing `TreatParams` enum pretty much mixes everything up. Not sure why this looked right to me in #94057

This also includes two changes which impact perf:
- `ty::Projection` with inference vars shouldn't be treated as a rigid type, even if fully normalized
- `ty::Placeholder` only unifies with itself, so actually return `Some` for them

r? `@nikomatsakis`
2022-05-19 13:08:51 +00:00
Jacob Pratt
f0620c9503 Proper const stability check, default to unstable
Rather than deferring to const eval for checking if a trait is const, we
now check up-front. This allows the error to be emitted earlier, notably
at the same time as other stability checks.

Also included in this commit is a change of the default const stability
level to UNstable. Previously, an item that was `const` but did not
explicitly state it was unstable was implicitly stable.
2022-05-19 12:21:45 +00:00