bors [Fri, 29 Jun 2018 16:48:57 +0000 (16:48 +0000)]
Auto merge of #51569 - SimonSapin:liballoc, r=sfackler
Make the public API of the alloc crate a subset of std
This only affects **unstable** APIs.
I plan to submit an RFC proposing to stabilize the crate. The reason it isn’t stable yet (https://github.com/rust-lang/rust/issues/27783) is in case we end up merging the standard library crates into one. However the `core` crate is already stable, so if that happens we’ll need to keep it working somehow (likely by making replacing its contents by `pub use` items). We can do the same for `alloc`. This PR will hopefully make this easier, but even if that doesn’t happen consistency with `std` seems good.
bors [Fri, 29 Jun 2018 12:40:12 +0000 (12:40 +0000)]
Auto merge of #51729 - matthewjasper:move-errors, r=nikomatsakis
[NLL] Better move errors
Make a number of changes to improve the quality of NLL cannot move errors.
* Group errors that occur in the same `match` with the same cause.
* Suggest `ref`, `&` or removing `*` to avoid the move.
* Show the place being matched on.
Differences from AST borrowck:
* `&` is suggested over `ref` when matching on a place that can't be moved from.
* Removing `*` is suggested instead of adding `&` when applicable.
* Sub-pattern spans aren't used, this would probably need Spans on Places.
bors [Fri, 29 Jun 2018 09:42:40 +0000 (09:42 +0000)]
Auto merge of #50526 - moxian:just-fix, r=alexcrichton
Add a fallback for stacktrace printing for older Windows versions.
Some time ago we switched stack inspection functions of dbghelp.dll to their newer alternatives that also capture inlined context.
Unfortunately, said new alternatives are not present in older dbghelp.dll versions.
In particular Windows 7 at the time of writing has dbghelp.dll version 6.1.7601 from 2010, that lacks StackWalkEx and friends.
Tested on my Windows 7 - both msvc and gnu versions produce a readable stacktrace.
bors [Fri, 29 Jun 2018 07:34:13 +0000 (07:34 +0000)]
Auto merge of #51290 - Pslydhh:master, r=alexcrichton
park/park_timeout: prohibit spurious wakeups in next park
<pre><code>
// The implementation currently uses the trivial strategy of a Mutex+Condvar
// with wakeup flag, which does not actually allow spurious wakeups.
</pre></code>
Because does not actually allow spurious wakeups.
so we have let thread.inner.cvar.wait(m) in the loop to prohibit spurious wakeups.
but if notified after we locked, this notification doesn't be consumed, it return, the next park will consume this notification...this is also 'spurious wakeup' case, 'one unpark() wakeups two park()'.
We should improve this situation：
`thread.inner.state.store(EMPTY, SeqCst);`
bors [Fri, 29 Jun 2018 04:09:02 +0000 (04:09 +0000)]
Auto merge of #50357 - seanmonstar:arc-weak-null, r=KodrAus
Arc: remove unused allocation from Weak::new()
It seems non-obvious that calling `Weak::new()` actually allocates space for the entire size of `T`, even though you can **never** access that data from such a constructed weak pointer. Besides that, if someone were to create many `Weak:new()`s, they could be unknowingly wasting a bunch of memory.
This change makes it so that `Weak::new()` allocates no memory at all. Instead, it is created with a null pointer. The only things done with a `Weak` are trying to upgrade, cloning, and dropping, meaning there are very few places that the code actually needs to check if the pointer is null.
Mark Rousskov [Thu, 28 Jun 2018 22:07:12 +0000 (16:07 -0600)]
Rollup merge of #51765 - jonas-schievink:patch-1, r=KodrAus
Use assert_eq! in copy_from_slice
This will print both lengths when the assertion fails instead of just saying that they're different.
Output of current stable and nightly (modulo the exact line number):
```
thread 'main' panicked at 'destination and source slices have different lengths', libcore/slice/mod.rs:1645:9
```
Output after this PR:
```
thread 'main' panicked at 'assertion failed: `(left == right)`
left: `123`,
right: `456`: destination and source slices have different lengths', libcore/slice/mod.rs:1645:9
```
moxian [Tue, 8 May 2018 06:19:55 +0000 (06:19 +0000)]
Add a fallback for stacktrace printing for older Windows versions.
PR #47252 switched stack inspection functions of dbghelp.dll
to their newer alternatives that also capture inlined context.
Unfortunately, said new alternatives are not present in older
dbghelp.dll versions.
In particular Windows 7 at the time of writing has dbghelp.dll
version 6.1.7601 from 2010, that lacks StackWalkEx and friends.
bors [Thu, 28 Jun 2018 13:23:07 +0000 (13:23 +0000)]
Auto merge of #51630 - joshlf:map-split-perf, r=dtolnay
Optimize RefCell refcount tracking
Address the performance concern raised in https://github.com/rust-lang/rust/pull/51466#issuecomment-398255276
cc @dtolnay @nnethercote @rust-lang/wg-compiler-performance
cc @RalfJung @jhjourdan for soundness concerns
Can somebody kick off a perf run on this? I'm not sure how that's done, but I understand it has to be started manually.
The idea of this change is to switch to representing mutable refcount as values below 0 to eliminate some branching that was required with the old algorithm.
bors [Thu, 28 Jun 2018 11:20:41 +0000 (11:20 +0000)]
Auto merge of #50997 - michaelwoerister:pre-analyze-filemaps, r=Mark-Simulacrum
Make FileMap::{lines, multibyte_chars, non_narrow_chars} non-mutable.
This PR removes most of the interior mutability from `FileMap`, which should be beneficial, especially in a multithreaded setting. This is achieved by initializing the state in question when the filemap is constructed instead of during lexing. Hopefully this doesn't degrade performance.
The method relied on the FileMap still being under construction in
order for it to do what the name promises. It's now independent of
the current state.
Namely: labels, type parameters, bindings in patterns, parameter names in functions without body.
All of these do not need hygiene after lowering to HIR, only span locations.
bors [Thu, 28 Jun 2018 03:57:28 +0000 (03:57 +0000)]
Auto merge of #51444 - estebank:impl-static, r=nikomatsakis
Suggestion for 'static impl Trait return
When encountering a named or anonymous sup requirement (for example,
`&'a self`) and a `'static` impl Trait return type, suggest adding the
`'_` lifetime constraing to the return type.
Fix #43719, #51282.
```
error: cannot infer an appropriate lifetime
--> $DIR/static-return-lifetime-infered.rs:17:16
|
LL | fn iter_values_anon(&self) -> impl Iterator<Item=u32> {
| ----------------------- this return type evaluates to the `'static` lifetime...
LL | self.x.iter().map(|a| a.0)
| ------ ^^^^
| |
| ...but this borrow...
|
note: ...can't outlive the anonymous lifetime #1 defined on the method body at 16:5
--> $DIR/static-return-lifetime-infered.rs:16:5
|
LL | / fn iter_values_anon(&self) -> impl Iterator<Item=u32> {
LL | | self.x.iter().map(|a| a.0)
LL | | }
| |_____^
help: you can add a constraint to the return type to make it last less than `'static` and match the anonymous lifetime #1 defined on the method body at 16:5
|
LL | fn iter_values_anon(&self) -> impl Iterator<Item=u32> + '_ {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
```
bors [Thu, 28 Jun 2018 01:41:40 +0000 (01:41 +0000)]
Auto merge of #51538 - nikomatsakis:nll-perf-examination, r=eddyb
convert NLL ops to caches
This is a extension of <https://github.com/rust-lang/rust/pull/51460>. It uses a lot more caching than we used to do. This caching is not yet as efficient as it could be, but I'm curious to see the current perf results.
This is the high-level idea: in the MIR type checker, use [canonicalized queries](https://rust-lang-nursery.github.io/rustc-guide/traits/canonical-queries.html) for all the major operations. This is helpful because the MIR type check is operating in a context where all types are fully known (mostly, anyway) but regions are completely renumbered. This means we often wind up with duplicate queries like `Foo<'1, '2> :Bar` and `Foo<'3, '4>: Bar`. Canonicalized queries let us re-use the results. By the final commit in this PR, we can essentially just "read off" the resulting region relations and add them to the NLL type check.
bors [Wed, 27 Jun 2018 23:41:23 +0000 (23:41 +0000)]
Auto merge of #51859 - kennytm:rollup, r=kennytm
Rollup of 7 pull requests
Successful merges:
- #49987 (Add str::split_ascii_whitespace.)
- #50342 (Document round-off error in `.mod_euc()`-method, see issue #50179)
- #51658 (Only do sanity check with debug assertions on)
- #51799 (Lower case some feature gate error messages)
- #51800 (Add a compiletest header for edition)
- #51824 (Fix the error reference for LocalKey::try_with)
- #51842 (Document that Layout::from_size_align does not allow align=0)
kennytm [Wed, 27 Jun 2018 22:15:39 +0000 (06:15 +0800)]
Rollup merge of #51658 - oli-obk:unregress_perf, r=nikomatsakis
Only do sanity check with debug assertions on
r? @nnethercote
I'm slighty confused. These changes address code that the `unused-warnings` benchmark doesn't go through, yet I see a 5% improvement to nightly on the `check` run, and no improvement on the other runs.
Maybe this change allows unrelated code in the same function to be better optimized?
kennytm [Wed, 27 Jun 2018 22:15:38 +0000 (06:15 +0800)]
Rollup merge of #50342 - fkjogu:euclidean, r=BurntSushi
Document round-off error in `.mod_euc()`-method, see issue #50179
Due to a round-off error the method `.mod_euc()` of both `f32` and `f64` can produce mathematical invalid outputs. If `self` in magnitude is much small than the modulus `rhs` and negative, `self + rhs` in the first branch cannot be represented in the given precision and results into `rhs`. In the mathematical strict sense, this breaks the definition. But given the limitation of floating point arithmetic it can be thought of the closest representable value to the true result, although it is not strictly in the domain `[0.0, rhs)` of the function. It is rather the left side asymptotical limit. It would be desirable that it produces the mathematical more sound approximation of `0.0`, the right side asymptotical limit. But this breaks the property, that `self == self.div_euc(rhs) * rhs + a.mod_euc(rhs)`.
The discussion in issue #50179 did not find an satisfying conclusion to which property is deemed more important. But at least we can document the behaviour. Which this pull request does.
kennytm [Wed, 27 Jun 2018 22:15:37 +0000 (06:15 +0800)]
Rollup merge of #49987 - clarcharr:split_ascii_whitespace, r=SimonSapin
Add str::split_ascii_whitespace.
As mentioned in #48656.
While `str::split_whitespace` now works in `libcore`, it still makes sense to offer this method, considering how it is still more performant in cases where only ASCII is necessary.
projects / rust.git / log