Fix `thread` `park`/`unpark` synchronization
Previously the code below would not be guaranteed to exit when the
second unpark took the `return, // already unparked` path because there
was no write to synchronize with a read in `park`.
EDIT: doesn't actually require third thread
```
use std::sync::atomic::{AtomicBool, Ordering};
use std:🧵:{current, spawn, park};
static FLAG: AtomicBool = AtomicBool::new(false);
fn main() {
let thread_0 = current();
spawn(move || {
thread_0.unpark();
FLAG.store(true, Ordering::Relaxed);
thread_0.unpark();
});
while !FLAG.load(Ordering::Relaxed) {
park();
}
}
```
I have some other ideas on how to improve the performance of `park` and `unpark` using fences, avoiding any atomic RMW when the state is already `NOTIFIED`, and also how to avoid calling `notify_one` without the mutex locked. But I need to write some micro benchmarks first, so I'll submit those changes at a later date if they prove to be faster.
Fixes https://github.com/rust-lang/rust/issues/53366 I hope.
In one of my travis builds, I was surprised to find that the gdb
pager was in use and caused travis to time out. Adding `--batch`
to the gdb invocation will disable the pager. Note that the
`-ex q` is retained, to make sure gdb exits with status 0, just in
case `set -e` is in effect somehow.
error[E0106]: missing lifetime specifier
--> /checkout/obj/build/x86_64-unknown-linux-gnu/test/error-index.md:11424:23
|
9 | fn demo(s: &mut S) -> &mut String { let p = &mut *(*s).data; p }
| ^ expected lifetime parameter
|
= help: this function's return type contains a borrowed value, but the signature does not say which one of `s`'s 2 lifetimes it is borrowed from
Update to a new pinning API.
~~Blocked on #53843 because of method resolution problems with new pin type.~~
@r? @cramertj
cc @RalfJung @pythonesque anyone interested in #49150
Use `HybridBitSet` in `SparseBitMatrix`.
This fixes most of the remaining NLL memory regression.
r? @pnkfelix, because you reviewed #54286.
cc @nikomatsakis, because NLL
cc @Mark-Simulacrum, because this removes `array_vec.rs`
cc @lqd, because this massively improves `unic-ucd-name`, and probably other public crates
By introducing a new map that tracks the errors reported and the
`Place`s that spawned those errors against the move out that the error
was referring to, we are able to silence duplicate errors by emitting
only the error which corresponds to the most specific `Place` (that which
other `Place`s which reported errors are prefixes of).
This generally is an improvement, however there is a case -
`liveness-move-in-while` - where the output regresses.
OsStr: Document that it's not NUL terminated
I somehow got confused into thinking this was the case, but
it's definitely not. Let's help the common case of people who
have an `OsStr` and need to call e.g. Unix APIs.
Remove README with now-out-of-date docs about docs.
These docs haven't really been touched in years, and from what I tried, the `rustdoc` commands don't work. Seems like we don't need this?
Issue 54246
I added the option of providing a help message for deprecated features, that takes precedence over the default `help: remove this attribute` message, along with messages for the features that mention replacements in the reason for deprecation.
Fixes#54246.
add `-Z dont-buffer-diagnostics`
Add `-Z dont-buffer-diagnostics`, a way to force NLL to immediately its diagnostics.
This is mainly intended for developers who want to see the error in its original context in the control flow. Two uses cases for that are:
1. `-Z treat-err-as-bug` (which then allows extraction of a stack-trace to the origin of the error)
2. RUST_LOG=... rustc, in which case it is often useful to see the logging statements that occurred immediately prior to the point where the diagnostic was signalled.
Regression test for rust-lang/rust#53675.
(Includes a couple variations on the theme. I confirmed that the ones
in `in_expression_position` and `what_if_we_use_panic_directly_in_expr`
both failed back on "rustc 1.30.0-nightly (0f063aef6 2018-09-03)".)
Fix#53675
Add doc for impl From for Addr
As part of issue #51430 (cc @skade).
The impl is very simple, let me know if we need to go into any details.
Additionally, I added `#[inline]` for the conversion method, let me know if it is un-necessary or might break something.
This requires adding a few extra methods to `HybridBitSet`. (These are
tested in a new unit test.)
This commit reduces the `max-rss` for `nll-check` builds of `html5ever`
by 46%, `ucd` by 45%, `clap-rs` by 23%, `inflate` by 14%. And the
results for the `unic-ucd-name` crate are even more impressive: a 21%
reduction in instructions, a 60% reduction in wall-time, a 96%
reduction in `max-rss`, and a 97% reduction in faults!
Fixes#52028.
`SparseBitSet` is the only remaining user of `ArrayVec`. This commit
switches it to using `SmallVec`, and removes `array_vec.rs`.
Why the switch? Although `SparseBitSet` is size-limited and doesn't need
the ability to spill to the heap, `SmallVec` has many more features than
`ArrayVec`. In particular, it's now possible to keep `SparseBitSet`'s
elements in sorted order, which gives in-order iteration, which is a
requirement for the next commit.
Merge `bitvec.rs` and `indexed_set.rs`
Because it's not good to have two separate implementations. Also, I will combine the best parts of each to improve NLL memory usage on some benchmarks significantly.
I somehow got confused into thinking this was the case, but
it's definitely not. Let's help the common case of people who
have an `OsStr` and need to call e.g. Unix APIs.
