Commit Graph

668 Commits

Author SHA1 Message Date
oli
3a44a20ed1 The proper name for the rule is "enclosing scope" 2021-01-01 16:59:12 +00:00
oli
0b841846ba Allow references to interior mutable data behind a feature gate 2021-01-01 16:59:12 +00:00
Mara Bos
067f1b7030
Rollup merge of #80491 - RalfJung:dangling-of-val, r=oli-obk
Miri: make size/align_of_val work for dangling raw ptrs

This is needed for https://github.com/rust-lang/rust/issues/80365#issuecomment-752128105.

r? `@oli-obk`
2020-12-30 20:56:56 +00:00
Mara Bos
46111c1901
Rollup merge of #80458 - RalfJung:promotion-refactor, r=oli-obk
Some Promotion Refactoring

Clean up promotion a bit:
* factor out some common code
* more exhaustive matches

This *should* not break anything... the only potentially-breaking change is that `BorrowKind::Shallow | BorrowKind::Unique` are now rejected for internal references.

r? ``@oli-obk``
2020-12-30 20:56:52 +00:00
bors
507bff92fa Auto merge of #80510 - JohnTitor:rollup-gow7y0l, r=JohnTitor
Rollup of 7 pull requests

Successful merges:

 - #80185 (Fix ICE when pointing at multi bytes character)
 - #80260 (slightly more typed interface to panic implementation)
 - #80311 (Improvements to NatVis support)
 - #80337 (Use `desc` as a doc-comment for queries if there are no doc comments)
 - #80381 (Revert "Cleanup markdown span handling")
 - #80492 (remove empty wraps, don't return Results from from infallible functions)
 - #80509 (where possible, pass slices instead of &Vec or &String (clippy::ptr_arg))

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2020-12-30 15:30:56 +00:00
bors
bbcaed03bf Auto merge of #79684 - usbalbin:const_copy, r=oli-obk
Make copy[_nonoverlapping] const

Constifies
* `intrinsics::copy` and `intrinsics::copy_nonoverlapping`
* `ptr::read` and `ptr::read_unaligned`
  * `*const T::read` and `*const T::read_unaligned`
  * `*mut T::read` and `*mut T::read_unaligned`
* `MaybeUninit::assume_init_read`
2020-12-30 12:43:02 +00:00
Matthias Krüger
bdc9291ed9 where possible, pass slices instead of &Vec or &String (clippy::ptr_arg) 2020-12-30 13:11:52 +01:00
Ralf Jung
95aed7ab3b Miri: make size/align_of_val work for dangling raw ptrs 2020-12-29 22:46:17 +01:00
Vadim Petrochenkov
4d2d0bad4e Remove compile-fail test suite 2020-12-29 23:39:56 +03:00
Ralf Jung
51cec58040 fix a comment 2020-12-29 16:32:38 +01:00
bors
e2a2592885 Auto merge of #79084 - simonvandel:instcombine-perf, r=oli-obk
Small perf changes for InstCombine
2020-12-29 06:21:18 +00:00
Ralf Jung
4a90a58c34 make more matches exhaustive 2020-12-28 23:29:16 +01:00
Simon Vandel Sillesen
0010fc8fec use exhaustive pattern match to prevent future bugs 2020-12-28 23:19:35 +01:00
Ralf Jung
c177e68015 merge two match'es for more exhaustiveness 2020-12-28 22:44:04 +01:00
Ralf Jung
122e91c4fb promotion: factor some common code into validate_ref 2020-12-28 22:09:08 +01:00
Albin Hedman
1b77f8e6ea Constify intrinsics::copy[_nonoverlapping] 2020-12-26 02:22:29 +01:00
bors
bb178237c5 Auto merge of #80235 - RalfJung:validate-promoteds, r=oli-obk
validate promoteds

Turn on const-value validation for promoteds. This is made possible now that https://github.com/rust-lang/rust/issues/67534 is resolved.

I don't think this is a breaking change. We don't promote any unsafe operation any more (since https://github.com/rust-lang/rust/pull/77526 landed). We *do* promote `const fn` calls under some circumstances (in `const`/`static` initializers), but union field access and similar operations are not allowed in `const fn`. So now is a perfect time to add this check. :D

r? `@oli-obk`
Fixes https://github.com/rust-lang/rust/issues/67465
2020-12-25 18:25:48 +00:00
bors
9a40539c38 Auto merge of #80364 - Dylan-DPC:rollup-0y96okz, r=Dylan-DPC
Rollup of 11 pull requests

Successful merges:

 - #79213 (Stabilize `core::slice::fill`)
 - #79999 (Refactored verbose print into a function)
 - #80160 (Implemented a compiler diagnostic for move async mistake)
 - #80274 (Rename rustc_middle::lint::LintSource)
 - #80280 (Add installation commands to `x` tool README)
 - #80319 (Fix elided lifetimes shown as `'_` on async functions)
 - #80327 (Updated the match with the matches macro)
 - #80330 (Fix typo in simplify_try.rs)
 - #80340 (Don't unnecessarily override attrs for Module)
 - #80342 (Fix typo)
 - #80352 (BTreeMap: make test cases more explicit on failure)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2020-12-25 05:23:24 +00:00
Dylan DPC
704f81e3cb
Rollup merge of #80330 - eltociear:patch-2, r=lcnr
Fix typo in simplify_try.rs

assigment -> assignment
2020-12-25 03:39:46 +01:00
Dylan DPC
787b016957
Rollup merge of #79999 - hencrice:yenlinc/79799, r=oli-obk
Refactored verbose print into a function

Also handle Tuple and Array separately, which was not explicitly checked.

Fixes #79799.
2020-12-25 03:39:33 +01:00
bors
cae1f4ddf2 Auto merge of #79762 - Swatinem:remap-doctest-coverage, r=Swatinem
Remap instrument-coverage line numbers in doctests

This uses the `SourceMap::doctest_offset_line` method to re-map line
numbers from doctests. Remapping columns is not yet done, and rustdoc
still does not output the correct filename when running doctests in a
workspace.

Part of #79417 although I dont consider that fixed until both filenames
and columns are mapped correctly.

r? `@richkadel`

I might jump on zulip the comming days. Still need to figure out how to properly write tests for this, and deal with other doctest issues in the meantime.
2020-12-25 02:37:08 +00:00
bors
c34c015fe2 Auto merge of #77692 - PankajChaudhary5:issue-76630, r=davidtwco
Added better error message for shared borrow treated as unique for purposes of lifetimes

Part of Issue #76630

r? `@jyn514`
2020-12-24 07:32:19 +00:00
Yenlin Chen
ecba49c1bd Fixed formatting 2020-12-23 19:10:59 +00:00
Yenlin Chen
f459b0fea5 Addressed feedbacks
Also updated the mir-opt test output files.
2020-12-23 18:55:37 +00:00
Ikko Ashimine
87397080b6
Fix typo in simplify_try.rs
assigment -> assignment
2020-12-23 21:11:59 +09:00
bors
11c94a1977 Auto merge of #79270 - RalfJung:array-repeat-consts, r=oli-obk
Acknowledge that `[CONST; N]` is stable

When `const_in_array_repeat_expressions` (RFC 2203) got unstably implemented as part of https://github.com/rust-lang/rust/pull/61749, accidentally, the special case of repeating a *constant* got stabilized immediately. That is why the following code works on stable:

```rust
const EMPTY: Vec<i32> = Vec::new();

pub const fn bar() -> [Vec<i32>; 2] {
    [EMPTY; 2]
}

fn main() {
    let x = bar();
}
```

In contrast, if we had written `[expr; 2]` for some expression that is not *literally* a constant but could be evaluated at compile-time (e.g. `(EMPTY,).0`), this would have failed.

We could take back this stabilization as it was clearly accidental. However, I propose we instead just officially accept this and stabilize a small subset of RFC 2203, while leaving the more complex case of general expressions that could be evaluated at compile-time unstable. Making that case work well is pretty much blocked on inline `const` expressions (to avoid relying too much on [implicit promotion](https://github.com/rust-lang/const-eval/blob/master/promotion.md)), so it could take a bit until it comes to full fruition. `[CONST; N]` is an uncontroversial subset of this feature that has no semantic ambiguities, does not rely on promotion, and basically provides the full expressive power of RFC 2203 but without the convenience (people have to define constants to repeat them, possibly using associated consts if generics are involved).

Well, I said "no semantic ambiguities", that is only almost true... the one point I am not sure about is `[CONST; 0]`. There are two possible behaviors here: either this is equivalent to `let x = CONST; [x; 0]`, or it is a NOP (if we argue that the constant is never actually instantiated). The difference between the two is that if `CONST` has a destructor, it should run in the former case (but currently doesn't, due to https://github.com/rust-lang/rust/issues/74836); but should not run if it is considered a NOP. For regular `[x; 0]` there seems to be consensus on running drop (there isn't really an alternative); any opinions for the `CONST` special case? Should this instantiate the const only to immediately run its destructors? That seems somewhat silly to me. After all, the `let`-expansion does *not* work in general, for `N > 1`.

Cc `@rust-lang/lang` `@rust-lang/wg-const-eval`
Cc https://github.com/rust-lang/rust/issues/49147
2020-12-21 13:12:36 +00:00
Dylan DPC
000c51611c
Rollup merge of #80199 - RalfJung:const-fake, r=oli-obk
also const-check FakeRead

We need to const-check all statements, including `FakeRead`, to avoid issues like https://github.com/rust-lang/rust/issues/77694.

Fixes https://github.com/rust-lang/rust/issues/77694.
r? ``@oli-obk``
2020-12-21 02:47:42 +01:00
Ralf Jung
97cae9c555 promoteds in statics may refer to statics 2020-12-20 19:34:29 +01:00
Ralf Jung
06ca7b700c validate promoteds 2020-12-20 15:54:20 +01:00
Ralf Jung
54a3ed3114 use exhaustive match for checking Rvalue::Repeat 2020-12-20 15:15:28 +01:00
bors
b1964e60b7 Auto merge of #80163 - jackh726:binder-refactor-part-3, r=lcnr
Make BoundRegion have a kind of BoungRegionKind

Split from #76814

Also includes making `replace_escaping_bound_vars` only return `T`

Going to r? `@lcnr`
Feel free to reassign
2020-12-20 07:01:00 +00:00
Ralf Jung
f4085f0d3a also const-check FakeRead 2020-12-19 20:52:24 +01:00
Arpad Borsos
830ceaa419 Remap instrument-coverage line numbers in doctests
This uses the `SourceMap::doctest_offset_line` method to re-map line
numbers from doctests. Remapping columns is not yet done.

Part of issue #79417.
2020-12-19 13:22:24 +01:00
Yuki Okushi
6b52475c68
Rollup merge of #80133 - Aaron1011:fix/const-mut-deref, r=estebank
Suppress `CONST_ITEM_MUTATION` lint if a dereference occurs anywhere

Fixes #79971
2020-12-19 15:16:08 +09:00
Jack Huey
328fcee4af Make BoundRegion have a kind of BoungRegionKind 2020-12-18 15:27:28 -05:00
Joshua Nelson
35f16c60e7 Switch compiler/ to intra-doc links
rustc_lint and rustc_lint_defs weren't switched because they're included
in the compiler book and so can't use intra-doc links.
2020-12-18 15:22:51 -05:00
Dylan DPC
720b6941df
Rollup merge of #78164 - Aaron1011:fix/async-region-name, r=tmandry
Prefer regions with an `external_name` in `approx_universal_upper_bound`

Fixes #75785

When displaying a MIR borrowcheck error, we may need to find an upper
bound for a region, which gives us a region to point to in the error
message. However, a region might outlive multiple distinct universal
regions, in which case the only upper bound is 'static

To try to display a meaningful error message, we compute an
'approximate' upper bound by picking one of the universal regions.
Currently, we pick the region with the lowest index - however, this
caused us to produce a suboptimal error message in issue #75785

This PR `approx_universal_upper_bound` to prefer regions with an
`external_name`. This causes us to prefer regions from function
arguments/upvars, which seems to lead to a nicer error message in some
cases.
2020-12-18 00:30:09 +01:00
Aaron Hill
dea13632a8
Suppress CONST_ITEM_MUTATION lint if a dereference occurs anywhere
Fixes #79971
2020-12-17 15:25:55 -05:00
Aaron Hill
419d3ae028
Prefer regions with an external_name in approx_universal_upper_bound
Fixes #75785

When displaying a MIR borrowcheck error, we may need to find an upper
bound for a region, which gives us a region to point to in the error
message. However, a region might outlive multiple distinct universal
regions, in which case the only upper bound is 'static

To try to display a meaningful error message, we compute an
'approximate' upper bound by picking one of the universal regions.
Currently, we pick the region with the lowest index - however, this
caused us to produce a suboptimal error message in issue #75785

This PR `approx_universal_upper_bound` to prefer regions with an
`external_name`. This causes us to prefer regions from function
arguments/upvars, which seems to lead to a nicer error message in some
cases.
2020-12-17 13:24:40 -05:00
bors
eb4fc71dc9 Auto merge of #79945 - jackh726:existential_trait_ref, r=nikomatsakis
Move binder for dyn to each list item

This essentially changes `ty::Binder<&'tcx List<ExistentialTraitRef>>` to `&'tcx List<ty::Binder<ExistentialTraitRef>>`.

This is a first step in moving the `dyn Trait` representation closer to Chalk, which we've talked about in `@rust-lang/wg-traits.`

r? `@nikomatsakis`
2020-12-17 18:21:20 +00:00
bors
caeb3335c0 Auto merge of #80114 - GuillaumeGomez:rollup-gszr5kn, r=GuillaumeGomez
Rollup of 5 pull requests

Successful merges:

 - #80006 (BTreeMap: more expressive local variables in merge)
 - #80022 (BTreeSet: simplify implementation of pop_first/pop_last)
 - #80035 (Optimization for bool's PartialOrd impl)
 - #80040 (Always run intrinsics lowering pass)
 - #80047 (Use more symbols in rustdoc)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2020-12-17 12:02:29 +00:00
Guillaume Gomez
1f5d8de062
Rollup merge of #80040 - tmiasko:always-lower-intrinsics, r=Dylan-DPC
Always run intrinsics lowering pass

Move intrinsics lowering pass from the optimization phase (where it
would not run if -Zmir-opt-level=0), to the drop lowering phase where it
runs unconditionally.

The implementation of those intrinsics in code generation and
interpreter is unnecessary. Remove it.
2020-12-17 11:36:52 +01:00
bors
001bd7762c Auto merge of #79840 - dvtkrlbs:issue-79667, r=oli-obk
Remove memoization leftovers from constant evaluation machine

Closes #79667
2020-12-17 09:11:28 +00:00
Yuki Okushi
a5b1d2252f
Rollup merge of #80072 - richkadel:llvm-coverage-counters-2.2.1, r=tmandry
Fixed conflict with drop elaboration and coverage

See
https://github.com/rust-lang/rust/issues/80045#issuecomment-745733339

Coverage statements are moved to the beginning of the BCB. This does
also affect what's counted before a panic, changing some results, but I
think these results may even be preferred? In any case, there are no
guarantees about what's counted when a panic occurs (by design).

r? `@tmandry`

FYI `@wesleywiser` `@ecstatic-morse`
2020-12-17 11:44:06 +09:00
Yuki Okushi
a611f8dbfc
Rollup merge of #79882 - wecing:master, r=oli-obk
Fix issue #78496

EarlyOtherwiseBranch finds MIR structures like:

```
bb0: {
  ...
  _2 = discriminant(X)
  ...
  switchInt(_2) -> [1_isize: bb1, otherwise: bb3]
}
bb1: {
  ...
  _3 = discriminant(Y)
  ...
  switchInt(_3) -> [1_isize: bb2, otherwise: bb3]
}
bb2: {...}
bb3: {...}
```

And transforms them into something like:

```
bb0: {
  ...
  _2 = discriminant(X)
  _3 = discriminant(Y)
  _4 = Eq(_2, _3)
  switchInt(_4) -> [true: bb4, otherwise: bb3]
}
bb2: {...} // unchanged
bb3: {...} // unchanged
bb4: {
  switchInt(_2) -> [1_isize: bb2, otherwise: bb3]
}
```

But that is not always a safe thing to do -- sometimes the early `otherwise` branch is necessary so the later block could assume the value of `discriminant(X)`.

I am not totally sure what's the best way to detect that, but fixing #78496 should be easy -- we just check if `X` is a sub-expression of `Y`. A more precise test might be to check if `Y` contains a `Downcast(1)` of `X`, but I think this might be good enough.

Fix #78496
2020-12-17 11:43:59 +09:00
Rich Kadel
1d6b455fb4 Fixed conflict with drop elaboration and coverage
See
https://github.com/rust-lang/rust/issues/80045#issuecomment-745733339

Coverage statements are moved to the beginning of the BCB. This does
also affect what's counted before a panic, changing some results, but I
think these results may even be preferred? In any case, there are no
guarantees about what's counted when a panic occurs (by design).
2020-12-15 23:33:47 -08:00
bors
4031f7b0a8 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
Guillaume Gomez
5de0c5f63f
Rollup merge of #79958 - richkadel:llvm-coverage-counters-2.2.0, r=tmandry
Fixes reported bugs in Rust Coverage

Fixes: #79569

Fixes: #79566
Fixes: #79565

For the first issue (#79569), I got hit a `debug_assert!()` before
encountering the reported error message (because I have `debug = true`
enabled in my config.toml).

The assertion showed me that some `SwitchInt`s can have more than one
target pointing to the same `BasicBlock`.

I had thought that was invalid, but since it seems to be possible, I'm
allowing this now.

I added a new test for this.

----

In the last two cases above, both tests (intentionally) fail to compile,
but the `InstrumentCoverage` pass is invoked anyway.

The MIR starts with an `Unreachable` `BasicBlock`, which I hadn't
encountered before. (I had assumed the `InstrumentCoverage` pass
would only be invoked with MIRs from successful compilations.)

I don't have test infrastructure set up to test coverage on files that
fail to compile, so I didn't add a new test.

r? `@tmandry`
FYI: `@wesleywiser`
2020-12-15 16:43:23 +01:00
bors
99baddb57c Auto merge of #78068 - RalfJung:union-safe-assign, r=nikomatsakis
consider assignments of union field of ManuallyDrop type safe

Assigning to `Copy` union fields is safe because that assignment will never drop anything. However, with https://github.com/rust-lang/rust/pull/77547, unions may also have `ManuallyDrop` fields, and their assignments are currently still unsafe. That seems unnecessary though, as assigning `ManuallyDrop` does not drop anything either, and is thus safe even for union fields.

I assume this will at least require FCP.
2020-12-15 11:31:03 +00:00
bors
e99a89c7c0 Auto merge of #73210 - wesleywiser:consts_in_debuginfo, r=oli-obk
[mir-opt] Allow debuginfo to be generated for a constant or a Place

Prior to this commit, debuginfo was always generated by mapping a name
to a Place. This has the side-effect that `SimplifyLocals` cannot remove
locals that are only used for debuginfo because their other uses have
been const-propagated.

To allow these locals to be removed, we now allow debuginfo to point to
a constant value. The `ConstProp` pass detects when debuginfo points to
a local with a known constant value and replaces it with the value. This
allows the later `SimplifyLocals` pass to remove the local.
2020-12-15 08:46:00 +00:00