Commit Graph

1469 Commits

Author SHA1 Message Date
Jacob Hughes
0266c134a7 Deprecate LayoutErr 2020-10-08 01:19:21 -04:00
Jacob Hughes
bf0adc3c36 Rename LayoutErr to LayoutError outside of core 2020-10-08 00:40:10 -04:00
Jacob Hughes
a97abb40ab Rename LayoutErr to LayoutError in core 2020-10-08 00:39:18 -04:00
bors
4437b4b150 Auto merge of #77464 - ecstatic-morse:const-fn-impl-trait, r=oli-obk
Give `impl Trait` in a `const fn` its own feature gate

...previously it was gated under `#![feature(const_fn)]`.

I think we actually want to do this in all const-contexts? If so, this should be `#![feature(const_impl_trait)]` instead. I don't think there's any way to make use of `impl Trait` within a `const` initializer.

cc #77463

r? `@oli-obk`
2020-10-07 19:59:52 +00:00
bors
28928c750c Auto merge of #77617 - AnthonyMikh:slice_windows_no_bounds_checking, r=lcnr
Eliminate bounds checking in slice::Windows

This is how `<core::slice::Windows as Iterator>::next` looks right now:

```rust
fn next(&mut self) -> Option<&'a [T]> {
    if self.size > self.v.len() {
        None
    } else {
        let ret = Some(&self.v[..self.size]);
        self.v = &self.v[1..];
        ret
    }
}
```

The line with `self.v = &self.v[1..];` relies on assumption that `self.v` is definitely not empty at this point. Else branch is taken when `self.size <= self.v.len()`, so `self.v` can be empty if `self.size` is zero. In practice, since `Windows` is never created directly but rather trough `[T]::windows` which panics when `size` is zero, `self.size` is never zero. However, the compiler doesn't know about this check, so it keeps the code which checks bounds and panics.

Using `NonZeroUsize` lets the compiler know about this invariant and reliably eliminate bounds checking without `unsafe` on `-O2`. Here is assembly of `Windows<'a, u32>::next` before and after this change ([goldbolt](https://godbolt.org/z/xrefzx)):

<details>
<summary>Before</summary>

```
example::next:
        push    rax
        mov     rcx, qword ptr [rdi + 8]
        mov     rdx, qword ptr [rdi + 16]
        cmp     rdx, rcx
        jbe     .LBB0_2
        xor     eax, eax
        pop     rcx
        ret
.LBB0_2:
        test    rcx, rcx
        je      .LBB0_5
        mov     rax, qword ptr [rdi]
        mov     rsi, rax
        add     rsi, 4
        add     rcx, -1
        mov     qword ptr [rdi], rsi
        mov     qword ptr [rdi + 8], rcx
        pop     rcx
        ret
.LBB0_5:
        lea     rdx, [rip + .L__unnamed_1]
        mov     edi, 1
        xor     esi, esi
        call    qword ptr [rip + core::slice::slice_index_order_fail@GOTPCREL]
        ud2

.L__unnamed_2:
        .ascii  "./example.rs"

.L__unnamed_1:
        .quad   .L__unnamed_2
        .asciz  "\f\000\000\000\000\000\000\000\016\000\000\000\027\000\000"
```

</details>

<details>
<summary>After</summary>

```
example::next:
        mov     rcx, qword ptr [rdi + 8]
        mov     rdx, qword ptr [rdi + 16]
        cmp     rdx, rcx
        jbe     .LBB0_2
        xor     eax, eax
        ret
.LBB0_2:
        mov     rax, qword ptr [rdi]
        lea     rsi, [rax + 4]
        add     rcx, -1
        mov     qword ptr [rdi], rsi
        mov     qword ptr [rdi + 8], rcx
        ret
```

</details>

Note the lack of call to `core::slice::slice_index_order_fail` in second snippet.

#### Possible reasons _not_ to merge this PR:

* this changes the error message on panic in `[T]::windows`. However, AFAIK this messages are not covered by backwards compatibility policy.
2020-10-07 17:31:56 +00:00
bors
c9ced8523b Auto merge of #77626 - tamird:parse-scope-id, r=dtolnay
Parse SocketAddrV6::scope_id

r? `@dtolnay`
2020-10-07 03:11:06 +00:00
bors
5779815f89 Auto merge of #74194 - mbrubeck:slice-eq, r=sfackler
Add PartialEq impls for Vec <-> slice

This is a follow-up to #71660 and rust-lang/rfcs#2917 to add two more missing vec/slice PartialEq impls:

```
impl<A, B> PartialEq<[B]> for Vec<A> where A: PartialEq<B> { .. }
impl<A, B> PartialEq<Vec<B>> for [A] where A: PartialEq<B> { .. }
```

Since this is insta-stable, it should go through the `@rust-lang/libs` FCP process.  Note that I used version 1.47.0 for the `stable` attribute because I assume this will not merge before the 1.46.0 branch is cut next week.
2020-10-07 01:20:11 +00:00
bors
59dafb876e Auto merge of #77630 - Dylan-DPC:rollup-kfwl55z, r=Dylan-DPC
Rollup of 11 pull requests

Successful merges:

 - #76784 (Add some docs to rustdoc::clean::inline and def_id functions)
 - #76911 (fix VecDeque::iter_mut aliasing issues)
 - #77400 (Fix suggestions for x.py setup)
 - #77515 (Update to chalk 0.31)
 - #77568 (inliner: use caller param_env)
 - #77571 (Use matches! for core::char methods)
 - #77582 (Move `EarlyOtherwiseBranch` to mir-opt-level 2)
 - #77590 (Update RLS and Rustfmt)
 - #77605 (Fix rustc_def_path to show the full path and not the trimmed one)
 - #77614 (Let backends access span information)
 - #77624 (Add c as a shorthand check alternative for new options #77603)

Failed merges:

r? `@ghost`
2020-10-06 23:07:17 +00:00
Dylan DPC
5314c72de8
Rollup merge of #77571 - pickfire:patch-6, r=cramertj
Use matches! for core::char methods
2020-10-07 00:16:07 +02:00
Dylan DPC
5ae45ea4e2
Rollup merge of #76911 - RalfJung:vecdeque-aliasing, r=oli-obk
fix VecDeque::iter_mut aliasing issues

Fixes https://github.com/rust-lang/rust/issues/74029
2020-10-07 00:15:59 +02:00
Tamir Duberstein
49ade22bd9
Parse SocketAddrV6::scope_id 2020-10-06 22:13:15 +00:00
Tamir Duberstein
a093957f43
Avoid unused return 2020-10-06 22:12:16 +00:00
bors
98edd1fbf8 Auto merge of #77386 - joshtriplett:static-glibc, r=petrochenkov
Support static linking with glibc and target-feature=+crt-static

With this change, it's possible to build on a linux-gnu target and pass
RUSTFLAGS='-C target-feature=+crt-static' or the equivalent via a
`.cargo/config.toml` file, and get a statically linked executable.

Update to libc 0.2.78, which adds support for static linking with glibc.

Add `crt_static_respected` to the `linux_base` target spec.

Update `android_base` and `linux_musl_base` accordingly. Avoid enabling
crt_static_respected on Android platforms, since that hasn't been
tested.

Closes https://github.com/rust-lang/rust/issues/65447.
2020-10-06 21:11:04 +00:00
AnthonyMikh
981cb8c191 Eliminate bounds checking in slice::Windows 2020-10-06 18:23:37 +03:00
bors
5849a7eca9 Auto merge of #77594 - timvermeulen:chain_advance_by, r=scottmcm
Implement advance_by, advance_back_by for iter::Chain

Part of #77404.

This PR does two things:
- implement `Chain::advance[_back]_by` in terms of `advance[_back]_by` on `self.a` and `advance[_back]_by` on `self.b`
- change `Chain::nth[_back]` to use `advance[_back]_by` on `self.a` and `nth[_back]` on `self.b`

This ensures that `Chain::nth` can take advantage of an efficient `nth` implementation on the second iterator, in case it doesn't implement `advance_by`.

cc `@scottmcm` in case you want to review this
2020-10-06 10:17:48 +00:00
Ralf Jung
fa6a4f7d37 avoid unnecessary intermediate reference and improve safety comments 2020-10-06 10:54:43 +02:00
Yuki Okushi
cdaf8c5f71
Rollup merge of #77573 - pickfire:patch-7, r=jyn514
Hint doc use convert::identity relative link

r? @jyn514
2020-10-06 16:26:12 +09:00
Yuki Okushi
eac25fefaf
Rollup merge of #77528 - tamird:avoid-cast-net-parser, r=dtolnay
Avoid unchecked casts in net parser

Once this and #77426 are in, I'll send another PR adding scope id parsing.

r? @dtolnay
2020-10-06 16:26:02 +09:00
Yuki Okushi
d7123c2393
Rollup merge of #77228 - GuillaumeGomez:maybeuninit-examples, r=pickfire
Add missing examples for MaybeUninit

r? @Dylan-DPC
2020-10-06 16:26:00 +09:00
Yuki Okushi
59476e9e57
Rollup merge of #76388 - poliorcetics:system-time-document-panic, r=KodrAus
Add a note about the panic behavior of math operations on time objects

Fixes #71226.
2020-10-06 16:25:53 +09:00
Dylan MacKenzie
c4ef5fdf8f Remove fn from feature name 2020-10-05 21:44:00 -07:00
Dylan MacKenzie
c959eefa74 Add requisite feature gates in the standard library 2020-10-05 19:57:25 -07:00
Tim Vermeulen
1d27a508d1 Test with non-fused iterators 2020-10-06 00:48:34 +02:00
Tim Vermeulen
bcacfe1dbf Add tests 2020-10-05 22:55:48 +02:00
Tim Vermeulen
c5d6a0dd96 Implement iter::Chain::{advance_by, advance_back_by} 2020-10-05 22:55:48 +02:00
Ivan Tham
cb881d36ae
hint doc use intra-doc links
Co-authored-by: Joshua Nelson <joshua@yottadb.com>
2020-10-05 23:29:43 +08:00
Ivan Tham
5541456094
Hint doc use convert::identity relative link 2020-10-05 22:47:52 +08:00
Ivan Tham
9704911ecb
Use matches! for core::char methods 2020-10-05 22:29:07 +08:00
Guillaume Gomez
b1ce6190ae Add missing examples for MaybeUninit 2020-10-05 13:21:20 +02:00
Ralf Jung
69669cbdb2 make IterMut Send/Sync again 2020-10-05 09:12:56 +02:00
Ralf Jung
e4c1a3867f VecDeque: avoid more aliasing issues by working with raw pointers instead of references 2020-10-05 09:12:56 +02:00
Ralf Jung
f251dc446f VecDeque: fix incorrect &mut aliasing in IterMut::next/next_back 2020-10-05 09:12:54 +02:00
Josh Triplett
d9f29fd9ed Add comment explaining why libunwind doesn't need to link libgcc_eh 2020-10-04 22:12:08 -07:00
Josh Triplett
9d952cbe95 unwind: Move linux-gnu library linking to lib.rs and libc
This unifies it with the handling of `target-feature=+crt-static` on
other platforms, and allows for supporting static glibc in the future.
2020-10-04 22:12:07 -07:00
Josh Triplett
16ebf750cf Update libc to 0.2.79
This also fixes issues with inconsistent `unsafe` on functions.
2020-10-04 22:12:07 -07:00
Dylan DPC
9dbc9ed870
Rollup merge of #77514 - scottmcm:less-once-chain-once, r=estebank
Replace some once(x).chain(once(y)) with [x, y] IntoIter

Now that we have by-value array iterators that are [already used](25c8c53dd9/compiler/rustc_hir/src/def.rs (L305-L307))...

For example,
```diff
-        once(self.type_ns).chain(once(self.value_ns)).chain(once(self.macro_ns)).filter_map(|it| it)
+        IntoIter::new([self.type_ns, self.value_ns, self.macro_ns]).filter_map(|it| it)
```
2020-10-05 02:29:42 +02:00
Dylan DPC
23b1e3d772
Rollup merge of #77471 - ssomers:btree_cleanup_3, r=Mark-Simulacrum
BTreeMap: refactoring around edges, missed spots

Tweaks from #77244 (and more) that are really inconsistencies in #77005.

r? @Mark-Simulacrum
2020-10-05 02:29:38 +02:00
Dylan DPC
f1afed541e
Rollup merge of #77426 - tamird:sockaddr-scope-id, r=dtolnay
Include scope id in SocketAddrV6::Display

r? @tmandry

I couldn't find any unit tests for these functions.

cc @ghanan94 @brunowonka
2020-10-05 02:29:35 +02:00
Dylan DPC
fe087ece94
Rollup merge of #77395 - ssomers:btree_love_the_leaf_edge_comments, r=Mark-Simulacrum
BTreeMap: admit the existence of leaf edges in comments

The btree code is ambiguous about leaf edges (i.e., edges within leaf nodes). Iteration relies on them heavily, but some of the comments suggest there are no leaf edges (extracted from #77025)

r? @Mark-Simulacrum
2020-10-05 02:29:31 +02:00
Dylan DPC
583269d8c5
Rollup merge of #77219 - mightyiam:issue_77100, r=jyn514
core::global_allocator docs link to std::alloc::GlobalAlloc

Closes #77100
2020-10-05 02:29:29 +02:00
Dylan DPC
6c9e85726c
Rollup merge of #75853 - LeSeulArtichaut:core-intra-docs-3, r=jyn514
Use more intra-doc-links in `core::fmt`

This is a follow-up to #75819, which encountered some broken links due to #75176, so this PR contains the links that are blocked on #75176.

r? @jyn514
2020-10-05 02:29:23 +02:00
bors
beb5ae474d Auto merge of #77023 - HeroicKatora:len-missed-optimization, r=Mark-Simulacrum
Hint the maximum length permitted by invariant of slices

One of the safety invariants of references, and in particular of references to slices, is that they may not cover more than `isize::MAX` bytes. The unsafe `from_raw_parts` constructors of slices explicitly requires the caller to guarantee this fact. Violating it would also be UB with regards to the semantics of generated llvm code.

This effectively bounds the length of a (non-ZST) slice from above by a compile time constant. But when the length is loaded from a function argument it appears llvm is not aware of this requirement. The additional value range assertions allow some further elision of code branches, including overflow checks, especially in the presence of artithmetic on the indices.

This may have a performance impact, adding more code to a common method but allowing more optimization. I'm not quite sure, is the Rust side of const-prop strong enough to elide the irrelevant match branches?

Fixes: #67186
2020-10-04 21:08:06 +00:00
LeSeulArtichaut
17d3c0a178 Use more intra-doc-links in core::fmt 2020-10-04 22:33:22 +02:00
Andreas Molzer
e44784b875 Assume slice len is bounded by allocation size
Uses assume to check the length against a constant upper bound. The
inlined result then informs the optimizer of the sound value range.

This was tried with unreachable_unchecked before which introduces a
branch. This has the advantage of not being executed in sound code but
complicates basic blocks. It resulted in ~2% increased compile time in
some worst cases.

Add a codegen test for the assumption, testing the issue from #67186
2020-10-04 20:43:36 +02:00
Tamir Duberstein
f78a7ade61
Inline "eof" methods 2020-10-04 17:07:30 +00:00
Tamir Duberstein
9601724b11
Avoid unchecked casts in net parser 2020-10-04 16:57:54 +00:00
bors
a835b483fe Auto merge of #77527 - jonas-schievink:rollup-szgq5he, r=jonas-schievink
Rollup of 8 pull requests

Successful merges:

 - #77072 (Minor `hash_map` doc adjustments + item attribute orderings)
 - #77368 (Backport LLVM apfloat commit to rustc_apfloat)
 - #77445 (BTreeMap: complete the compile-time test_variance test case)
 - #77504 (Support vectors with fewer than 8 elements for simd_select_bitmask)
 - #77513 (Change DocFragments from enum variant fields to structs with a nested enum)
 - #77518 (Only use Fira Sans for the first `td` in item lists)
 - #77521 (Move target feature whitelist from cg_llvm to cg_ssa)
 - #77525 (Enable RenameReturnPlace MIR optimization on mir-opt-level >= 2)

Failed merges:

r? `@ghost`
2020-10-04 13:49:36 +00:00
Jonas Schievink
80953177ed
Rollup merge of #77445 - ssomers:btree_cleanup_7, r=Mark-Simulacrum
BTreeMap: complete the compile-time test_variance test case

Some of the items added to the new `test_sync` belonged in the old `test_variance` as well. And fixed inconsistent paths to nearby modules.
r? @Mark-Simulacrum
2020-10-04 15:45:41 +02:00
Jonas Schievink
4ae7710e1d
Rollup merge of #77072 - sharnoff:hash-docs, r=LukasKalbertodt
Minor `hash_map` doc adjustments + item attribute orderings

This PR is really a couple visual changes glued together:
1. Some of the doc comments for items in `std::collections::hash_map` referenced the names of types without escaping their formatting (e.g. using "VacantEntry" instead of "`VacantEntry`") - the ones I could find were changed to the latter
2. The vast majority of pre-item attributes seem to place doc comments as the first attribute (instead of things like `#[feature(...)]`), so the few that had the other order were changed.
3. Also ordering related: the general trend seems to be that `#[feature]` attributes follow `#[inline]`, so I swapped the two lines in places where that ordering was reversed. This is primarily a change based on stylistic continuity and aesthetics - I'm not sure how important that actually is / should be.

I figured this would be pretty uncontroversial, but some of these might have been intentional for reasons I don't know about - if so, I'd be happy to remove the relevant changes. Of these, the final set of changes is probably the most unnecessary, so it also might be better to leave those out (in favor of reducing code churn).
2020-10-04 15:45:33 +02:00
Tamir Duberstein
4585c22818
Include scope id in SocketAddrV6::Display 2020-10-04 12:18:12 +00:00